Hair dysplasias are congenital or acquired alterations which often involve the hair shaft. Hair shaft abnormalities are characterized by changes in color, density, length and structure. Hair shaft alterations often result from structural changes within the hair fibers and cuticles which may lead to brittle and uncombable hair. The hair of patients with hair shaft diseases feels dry and looks
Peter H. Itin; Susanna K. Fistarol
Root hairs are important for nutrient uptake, anchorage, and plant–microbe interactions. From a population of rice (Oryza sativa) mutagenized by ethyl methanesulfonate (EMS), a short root hair2 (srh2) mutant was identified. In hydroponic culture, srh2 seedlings were significantly reduced in root hair length. Bubble-like extrusions and irregular epidermal cells were observed at the tips of srh2 root hairs when grown under acidic conditions, suggesting the possible reduction of the tensile strength of the cell wall in this mutant. Map-based cloning identified a mutation in the gene encoding xyloglucan (XyG) 6-xylosyltransferase (OsXXT1). OsXXT1 displays more than 70% amino acid sequence identity with the previously characterized Arabidopsis thaliana XYG XYLOSYL TRANSFERASE 1 (AtXXT1) and XYG XYLOSYL TRANSFERASE 2 (AtXXT2), which catalyse the transfer of xylose onto ?-1,4-glucan chains. Furthermore, expression of the full-length coding sequence of OsXXT1 could complement the root hair defect, and slow growth and XyG synthesis in the Arabidopsis xxt1 xxt2 double mutant. Transgenic plants expressing the ?-glucuronidase (GUS) reporter under the control of the OsXXT1 promoter displayed GUS expression in multiple tissues, most prominently in root epidermal cells. These results demonstrate the importance of OsXXT1 in maintaining cell wall structure and tensile strength in rice, a typical grass species that contains relatively low XyG content in cell walls.
Wang, Chuang; Li, Shuai; Ng, Sophia; Zhang, Baocai; Zhou, Yihua; Whelan, James; Wu, Ping; Shou, Huixia
Root hairs are important for nutrient uptake, anchorage, and plant-microbe interactions. From a population of rice (Oryza sativa) mutagenized by ethyl methanesulfonate (EMS), a short root hair2 (srh2) mutant was identified. In hydroponic culture, srh2 seedlings were significantly reduced in root hair length. Bubble-like extrusions and irregular epidermal cells were observed at the tips of srh2 root hairs when grown under acidic conditions, suggesting the possible reduction of the tensile strength of the cell wall in this mutant. Map-based cloning identified a mutation in the gene encoding xyloglucan (XyG) 6-xylosyltransferase (OsXXT1). OsXXT1 displays more than 70% amino acid sequence identity with the previously characterized Arabidopsis thaliana XYG XYLOSYL TRANSFERASE 1 (AtXXT1) and XYG XYLOSYL TRANSFERASE 2 (AtXXT2), which catalyse the transfer of xylose onto ?-1,4-glucan chains. Furthermore, expression of the full-length coding sequence of OsXXT1 could complement the root hair defect, and slow growth and XyG synthesis in the Arabidopsis xxt1 xxt2 double mutant. Transgenic plants expressing the ?-glucuronidase (GUS) reporter under the control of the OsXXT1 promoter displayed GUS expression in multiple tissues, most prominently in root epidermal cells. These results demonstrate the importance of OsXXT1 in maintaining cell wall structure and tensile strength in rice, a typical grass species that contains relatively low XyG content in cell walls. PMID:24834920
Wang, Chuang; Li, Shuai; Ng, Sophia; Zhang, Baocai; Zhou, Yihua; Whelan, James; Wu, Ping; Shou, Huixia
Human hair disorders comprise a number of different types of alopecia, atrichia, hypotrichosis, distinct hair shaft disorders as well as hirsutism and hypertrichosis. Their causes vary from genodermatoses (e.g. hypotrichoses) via immunological disorders (e.g. alopecia areata, autoimmune cicatrical alopecias) to hormone-dependent abnormalities (e.g. androgenetic alopecia). A large number of spontaneous mouse mutants and genetically engineered mice develop abnormalities in hair follicle morphogenesis, cycling, and/or hair shaft formation, whose analysis has proven invaluable to define the molecular regulation of hair growth, ranging from hair follicle development, and cycling to hair shaft formation and stem cell biology. Also, the accumulating reports on hair phenotypes of mouse strains provide important pointers to better understand the molecular mechanisms underlying human hair growth disorders. Since numerous new mouse mutants with a hair phenotype have been reported since the publication of our earlier review on this matter a decade ago, we present here an updated, tabulated mini-review. The updated annotated tables list a wide selection of mouse mutants with hair growth abnormalities, classified into four categories: Mutations that affect hair follicle (1) morphogenesis, (2) cycling, (3) structure, and (4) mutations that induce extrafollicular events (for example immune system defects) resulting in secondary hair growth abnormalities. This synthesis is intended to provide a useful source of reference when studying the molecular controls of hair follicle growth and differentiation, and whenever the hair phenotypes of a newly generated mouse mutant need to be compared with existing ones. PMID:23165165
Nakamura, Motonobu; Schneider, Marlon R; Schmidt-Ullrich, Ruth; Paus, Ralf
SUMMARY The developments of hair dyes from herbal extracts are studied. Seven herbs, such as Jackfruit core, Sappan wood, Lac, Henna, Mangosteen, Amla and Turmeric were ex- tracted and used as pigment for hair dyes. The dyed hair conditions, which comprised concentrations of a developer (hydrogen peroxide), concentrations of crude herbal ex- tracts, and dyed hair treatment process were compared
Kongtun Janphuk Sumonthip; Suracherdkaiti Wichai
Summary Animal swimming tests, such as the forced swim test, are extensively used in biomedical research to study rodent behaviour. Hair and skin exposed to water may be an important factor affecting the performance in this test. Since various hair and skin abnormalities are not uncommon in genetically modified or drug-treated laboratory animals, this test may be inappropriate for these
A V Kalueff; P Tuohimaa
Hepatocyte growth factor activator inhibitor type 1 (HAI-1)/serine protease inhibitor, Kunitz type 1 (SPINT1) is a membrane-bound, serine proteinase inhibitor initially identified as an inhibitor of hepatocyte growth factor activator. It also inhibits matriptase and prostasin, both of which are membrane-bound serine proteinases that have critical roles in epidermal differentiation and function. In this study, skin and hair phenotypes of mice lacking the Hai-1/Spint1 gene were characterized. Previously, we reported that the homozygous deletion of Hai-1/Spint1 in mice resulted in embryonic lethality attributable to impaired placental development. To test the role of Hai-1/Spint1 in mice, the placental function of Hai-1/Spint1-mutant mice was rescued. Injection of Hai-1/Spint1(+/+) blastocysts with Hai-1/Spint1(-/-) embryonic stem cells successfully generated high-chimeric Hai-1/Spint1(-/-) embryos (B6Hai-1(-/-High)) with normal placentas. These embryos were delivered without apparent developmental abnormalities, confirming that embryonic lethality of Hai-1/Spint1(-/-) mice was caused by placental dysfunction. However, newborn B6Hai-1(-/-High) mice showed growth retardation and died by 16 days. These mice developed scaly skin because of hyperkeratinization, reminiscent of ichthyosis, and abnormal hair shafts that showed loss of regular cuticular septation. The interfollicular epidermis showed acanthosis with enhanced Akt phosphorylation. Immunoblot analysis revealed altered proteolytic processing of profilaggrin in Hai-1/Spint1-deleted skin with impaired generation of filaggrin monomers. These findings indicate that Hai-1/Spint1 has critical roles in the regulated keratinization of the epidermis and hair development. PMID:18832587
Nagaike, Koki; Kawaguchi, Makiko; Takeda, Naoki; Fukushima, Tsuyoshi; Sawaguchi, Akira; Kohama, Kazuyo; Setoyama, Mitsuru; Kataoka, Hiroaki
Purpose of review The identification of transcriptional activators and repressors of hair cell fates has recently been augmented by the discovery of microRNAs (miRNAs) that can function as post-transcriptional repressors in sensory hair cells. Recent findings miRNAs are ~21 nucleotide single-stranded ribonucleic acids that can each repress protein synthesis of many target genes by interacting with messenger RNA transcripts. A triplet of these miRNAs, the miR-183 family, are highly expressed in vertebrate hair cells, as well as a variety of other peripheral neurosensory cells. Point mutations in one member of this family, miR-96, underlie DFNA50 autosomal deafness in humans and lead to abnormal hair cell development and survival in mice. In zebrafish, overexpression of the miR-183 family induces extra and ectopic hair cells, while knockdown reduces hair cell numbers. Genetically-engineered mice with a block in miRNA biosynthesis during early ear development, or during hair cell differentiation, reveal the necessity of miRNAs at these crucial time points. Summary Because miRNAs can simultaneously down-regulate dozens to perhaps hundreds of transcripts, they will soon be explored as potential therapeutic agents to repair or regenerate hair cells in animal models.
Li, Haiqiong; Fekete, Donna M.
Hair dye poisoning has been emerging as one of the important causes of intentional self harm in the developing world. Hair dyes contain paraphenylene-diamine and a host of other chemicals that can cause rhabdomyolysis, laryngeal edema, severe metabolic acidosis and acute renal failure. Intervention at the right time has been shown to improve the outcome. In this article, we review the various manifestations, clinical features and treatment modalities for hair dye poisoning.
Sampathkumar, Krishnaswamy; Yesudas, Sooraj
Hair loss from cancer chemotherapy has received considerable attention in recent years in the field of cancer care because of the emotional and social distress it can cause patients. Many investigators have attempted to decrease hair loss by means of scal...
B. S. Mueggenborg
The in vivo functions of the activin A receptor type 1b (Acvr1b) have been difficult to study because Acvr1b?/? mice die during embryogenesis. To investigate the roles of Acvr1b in the epithelial tissues, we created mice with a conditional disruption of Acvr1b (Acvr1bflox/flox) and crossed them with K14-Cre mice. Acvr1bflox/flox; K14-Cre mice displayed various degrees of hairlessness at postnatal day 5, and the phenotype is exacerbated by age. Histological analyses showed that those hair follicles that developed during morphogenesis were later disrupted by delays in hair cycle reentry. Failure in cycling of the hair follicles and regrowth of the hair shaft and the inner root sheath resulted in subsequent severe hair loss. Apart from previous reports of other members of the transforming growth factor-?/activin/bone morphogenic protein pathways, we demonstrate a specialized role for Acvr1b in hair cycling in addition to hair follicle development. Acvr1bflox/flox; K14-Cre mice also had a thicker epidermis than did wild-type mice, which resulted from persistent proliferation of skin epithelial cells; however, no tumor formation was observed by 18 months of age. Our analysis of this Acvr1b knockout mouse line provides direct genetic evidence that Acvr1b signaling is required for both hair follicle development and cycling.
Qiu, Wanglong; Li, Xiaojun; Tang, Hongyan; Huang, Alicia S.; Panteleyev, Andrey A.; Owens, David M.; Su, Gloria H.
Clinical conditions causing hair loss, such as androgenetic alopecia, alopecia areata, and scarring alopecia, can be psychologically devastating to individuals and are the target of a multimillion dollar pharmaceutical industry. The importance of the hair follicle in skin biology, however, does not rest solely with its ability to produce hair. Hair follicles are self-renewing and contain reservoirs of multipotent stem
Sarah E. Millar
The plant hormone auxin controls root epidermal cell development in a concentration-dependent manner. Root hairs are produced on a subset of epidermal cells as they increase in distance from the root tip. Auxin is required for their initiation and continued growth, but little is known about its distribution in this region of the root. Contrary to the expectation that hair cells might require active auxin influx to ensure auxin supply, we did not detect the auxin-influx transporter AUX1 in root-hair cells. A high level of AUX1 expression was detected in adjacent non-hair cell files. Non-hair cells were necessary to achieve wild-type root-hair length, although an auxin response was not required in these cells. Three-dimensional modelling of auxin flow in the root tip suggests that AUX1-dependent transport through non-hair cells maintains an auxin supply to developing hair cells as they increase in distance from the root tip, and sustains root-hair outgrowth. Experimental data support the hypothesis that instead of moving uniformly though the epidermal cell layer, auxin is mainly transported through canals that extend longitudinally into the tissue. PMID:19079245
Jones, Angharad R; Kramer, Eric M; Knox, Kirsten; Swarup, Ranjan; Bennett, Malcolm J; Lazarus, Colin M; Leyser, H M Ottoline; Grierson, Claire S
The plant hormone auxin controls root epidermal cell development in a concentration-dependent manner 1-3. Root hairs are produced on a subset of epidermal cells as they increase in distance from the root tip. Auxin is required for their initiation 4-7 and continued growth 8-11, but little is known about its distribution in this region of the root. Counter to the expectation that hair cells might require active auxin influx to ensure auxin supply, we did not detect the auxin-influx transporter AUX1 in root-hair cells. A high level of AUX1 expression was detected in adjacent non-hair cell files. Non-hair cells were necessary to achieve wild-type root-hair length, although an auxin response was not required in these cells. 3D modelling of auxin flow in the root tip suggests that AUX1-dependent transport through non-hair cells maintains an auxin supply to developing hair cells as they increase in distance from the root tip and sustains root-hair outgrowth. Experimental data support the hypothesis that, instead of moving uniformly though the epidermal cell layer 3,12, auxin is mainly transported through canals that extend longitudinally into the tissue.
Jones, Angharad R.; Kramer, Eric M.; Knox, Kirsten; Swarup, Ranjan; Bennett, Malcolm J.; Lazarus, Colin M.; Leyser, H. M. Ottoline; Grierson, Claire S.
Ectodysplasin (Eda), a member of the tumor necrosis factor (Tnf) family, regulates skin appendage morphogenesis via its receptor Edar and transcription factor NF-?B. In humans, inactivating mutations in the Eda pathway components lead to hypohidrotic ectodermal dysplasia (HED), a syndrome characterized by sparse hair, tooth abnormalities, and defects in several cutaneous glands. A corresponding phenotype is observed in Eda-null mice, where failure in the initiation of the first wave of hair follicle development is a hallmark of HED pathogenesis. In an attempt to discover immediate target genes of the Eda/NF-?B pathway, we performed microarray profiling of genes differentially expressed in embryonic skin explants after a short exposure to recombinant Fc-Eda protein. Upregulated genes included components of the Wnt, fibroblast growth factor, transforming growth factor-?, Tnf, and epidermal growth factor families, indicating that Eda modulates multiple signaling pathways implicated in skin appendage development. Surprisingly, we identified two ligands of the chemokine receptor cxcR3, cxcl10 and cxcl11, as new hair-specific transcriptional targets of Eda. Deficiency in cxcR3 resulted in decreased primary hair follicle density but otherwise normal hair development, indicating that chemokine signaling influences the patterning of primary hair placodes only. PMID:22277947
Lefebvre, Sylvie; Fliniaux, Ingrid; Schneider, Pascal; Mikkola, Marja L
Despite increased interest in inner ear hair cell regeneration, it is still unclear what exact mechanisms underlie hair cell regener- ation in mammals because of our limited understanding of hair cell development and the lack of specific hair cell markers. In this report, we studied hair cell development using immunohis- tochemistry on sections prepared from embryonic day (E) 13 to
J. Lisa Zheng; Wei-Qiang Gao
Visual examination of roots from 12,000 mutagenized Arabidopsis seedlings has led to the identification of more than 40 mutants impaired in root hair morphogenesis. Mutants from four phenotypic classes have been characterized in detail, and genetic tests show that these result from single nuclear recessive mutations in four different genes designated RHD1, RHD2, RHD3, and RHD4. The phenotypic analysis of the mutants and homozygous double mutants has led to a proposed model for root hair development and the stages at which the genes are normally required. The RHD1 gene product appears to be necessary for proper initiation of root hairs, whereas the RHD2, RHD3, and RHD4 gene products are required for normal hair elongation. These results demonstrate that root hair development in Arabidopsis is amenable to genetic dissection and should prove to be a useful model system to study the molecular mechanisms governing cell differentiation in plants.
Schiefelbein, JW; Somerville, C
During hair follicle morphogenesis, melanocyte precursors migrate into developing hair follicles and give rise to differentiated melanocytes that actively produce and transport pigment into the keratinocytes that form the hair shaft; however, patterns of melanocyte proliferation and differentiation during formation of the hair pigmentation unit remain to be elucidated. Using multicolor confocal microscopy and double immunofluorescence of melanogenic proteins (tyrosinase-related
Natalia V. Botchkareva; Vladimir A. Botchkarev; Barbara A. Gilchrest
Hair follicle is an appendage from the vertebrate skin epithelium, and is critical for environmental sensing, animal appearance, and body heat maintenance. Hair follicles arise from the embryonic ectoderm and regenerate cyclically during adult life. Distinct morphological and functional stages from development through homeostasis have been extensively studied for the past decades to dissect the critical molecular mechanisms. Accumulating work suggests that different signaling cascades, such as Wnt, Bmp, Shh, and Notch, together with specific combinations of transcription factors are at work at different stages. Here we provide a comprehensive review of mouse genetics studies, which include lineage tracing along with knockout and over-expression of core genes from key signaling pathways, to paint an updated view of the molecular regulatory network that govern each stage of hair follicle development and adult cycling.
Lee, Jayhun; Tumbar, Tudorita
A 2-month-old white girl born to nonconsanguineous parents presented to the dermatology department with hair loss that had commenced a few months after birth. Although her hair loss later stabilized, it remained sparse. By the age of 2 years, she was noted to have developed focal keratoderma over pressure points of the soles. Aged 5 years, she was admitted to hospital with a chest infection, and investigations at that point revealed that she had a dilated cardiomyopathy. Subsequent genetic investigations identified compound heterozygous mutations in the 3' end of the desmoplakin (DSP) gene (7567delAAGA and 6577G>A), explaining the cardiocutaneous phenotype. PMID:24825141
Yesudian, P D; Cabral, R M; Ladusans, E; Spinty, S; Gibbs, J; Fryer, A; Christiano, A M; Mendelsohn, S S
Hair follicle morphogenesis depends on Wnt, Shh, Notch, BMP and other signaling pathways interplay between epithelial and mesenchymal cells. The Wnt pathway plays an essential role during hair follicle induction, Shh is involved in morphogenesis and late stage differentiation, Notch signaling determines stem cell fate while BMP is involved in cellular differentiation. The Wnt pathway is considered to be the master regulator during hair follicle morphogenesis. Wnt signaling proceeds through EDA/EDAR/NF-?B signaling. NF-?B regulates the Wnt pathway and acts as a signal mediator by upregulating the expression of Shh ligand. Signal crosstalk between epithelial and mesenchymal cells takes place mainly through primary cilia. Primary cilia formation is initiated with epithelial laminin-511 interaction with dermal ?-1 integrin, which also upregulates expression of downstream effectors of Shh pathway in dermal lineage. PDGF signal transduction essential for crosstalk is mediated through epithelial PDGF-A and PDGFR? expressed on the primary cilia. Dermal Shh and PDGF signaling up-regulates dermal noggin expression; noggin is a potent inhibitor of BMP signaling which helps in counteracting BMP mediated ?-catenin inhibition. This interplay of signaling between the epithelial and dermal lineage helps in epithelial Shh signal amplification. The dermal Wnt pathway helps in upregulation of epithelial Notch expression. Dysregulation of these pathways leads to certain abnormalities and in some cases even tumor outgrowth. PMID:24451143
Rishikaysh, Pisal; Dev, Kapil; Diaz, Daniel; Qureshi, Wasay Mohiuddin Shaikh; Filip, Stanislav; Mokry, Jaroslav
We previously described an autosomal-recessive mutation named nackt (nkt) exhibiting partial alopecia associated with CD4+ T-cell deficiency. Also, we recently reported that nkt (now Ctslnkt) comprises a deletion in the cathepsin L (Ctsl) gene. Another recent study reported that Ctsl knockout mice have CD4+ T-cell deficiency and periodic shedding of hair, which recapitulate the nkt mutation and the old furless (fs) mutation. The current study focuses on the dermatological aspects of the nkt mutation. Careful histological analysis of skin development of homozygous nkt mice revealed a delayed hair follicle morphogenesis and late onset of the first catagen stage. The skin of Ctslnkt/Ctslnkt mice showed mild epidermal hyperplasia and hyperkeratosis, severe hyperplasia of the sebaceous glands, and structural alterations of hair follicles. Epidermal differentiation seems to be affected in nkt skin, with overexpression of involucrin and profilaggrin/filaggrin along with focal areas of keratin 6 expression in the interfollicular epidermis. Severe epidermal hyperplasia, acanthosis, orthokeratosis, and hyperkeratosis were only observed in mice maintained in nonpathogen-free environments. The analysis of Rag2?/? Ctslnkt/Ctslnkt double-mutant mice indicates that the skin defect remains under the absence of T and B cells. This animal model provides in vivo evidence that cysteine protease cathepsin L plays a critical role in hair follicle morphogenesis and cycling, as well as epidermal differentiation.
Benavides, Fernando; Starost, Matthew F.; Flores, Monica; Gimenez-Conti, Irma B.; Guenet, Jean-Louis; Conti, Claudio J.
Root hair development is controlled by environmental signals. Studies on root hair plasticity in Arabidopsis thaliana have mainly focused on phosphate and iron deficiency. Root hair growth and development and their physiological role in response\\u000a to salt stress are largely unknown. Here, we show that root epidermal cell types and root hair development are highly regulated\\u000a by salt stress. Root
Youning Wang; Wensheng Zhang; Kexue Li; Feifei Sun; Chunyu Han; Yukun Wang; Xia Li
We show that neural crest stem cells affect mouse hair follicle development. During embryogenesis hair follicle induction is regulated by complex reciprocal and functionally redundant signals between epidermis and dermis, which remain to be fully understood. Canonical Wnt signalling is a hallmark of neural crest cells and also a prerequisite for hair follicle induction prior to hair placode formation in the epidermis. As neural crest stem cells invade the epidermis during early embryonic development we aimed at determining whether neural crest cells affect hair follicle development. To attenuate, but not silence, canonical Wnt signalling specifically in neural crest cells, we analyzed Wnt1-cre(+/-)::Pygo2(-/-) mice in which the ?-catenin co-activator gene, Pygopus 2 (Pygo2), is deleted specifically in neural crest cells. Both, hair density and hair thickness were reduced in mutant mice. Furthermore, hair development was delayed and the relative ratio of hair types was affected. There was a decrease in zig-zag hairs and an increase in awl hairs. Mouse neural crest stem cells expressed ectodysplasin, an essential effector in the formation of zig-zag hair. Taken together, our data support the novel notion that neural crest cells are involved in the earliest stages of hair follicle development. PMID:23955574
Narytnyk, Alla; Gillinder, Kevin; Verdon, Bernard; Clewes, Oliver; Sieber-Blum, Maya
In this paper, a tactile sensor system for evaluation of human hair under dry and wet conditions is developed. The polyvinylidene\\u000a fluoride (PVDF) film is used as the sensory material. The sensor consists of an acrylic base, a silicone rubber, a PVDF film.\\u000a A surface projection is put on the PVDF film as the contacting part. The sensor output is
Takeshi Okuyama; Makoto Hariu; Tomoyuki Kawasoe; Minori Kakizawa; Hideki Shimizu; Mami Tanaka
Background Hearing restoration through hair cell regeneration will require revealing the dynamic interactions between proliferation and differentiation during development to avoid the limited viability of regenerated hair cells. Pax2-Cre N-Myc conditional knockout (CKO) mice highlighted the need of N-Myc for proper neurosensory development and possible redundancy with L-Myc. The late-onset hair cell death in the absence of early N-Myc expression could be due to mis-regulation of genes necessary for neurosensory formation and maintenance, such as Neurod1, Atoh1, Pou4f3, and Barhl1. Results Pax2-Cre N-Myc L-Myc double CKO mice show that proliferation and differentiation are linked together through Myc and in the absence of both Mycs, altered proliferation and differentiation results in morphologically abnormal ears. In particular, the organ of Corti apex is re-patterned into a vestibular-like organization and the base is truncated and fused with the saccule. Conclusions These data indicate that therapeutic approaches to restore hair cells must take into account a dynamic interaction of proliferation and differentiation regulation of basic Helix-Loop-Helix transcription factors in attempts to stably replace lost cochlear hair cells. In addition, our data indicate that Myc is an integral component of the evolutionary transformation process that resulted in the organ of Corti development.
Kopecky, Benjamin J.; Jahan, Israt; Fritzsch, Bernd
Many advances in the cosmetic industry have increased our ability to enhance youth and beauty. Hair-coloring products are one such innovation. Over the past several decades, a significant amount of work has been dedicated to understanding the possible long-term side effects associated with hair-dye use, specifically looking at cancer risk. This paper describes the hair-coloring process, highlights the potentially carcinogenic ingredients in various hair-dying products, and reviews the epidemiological evidence relating personal hair-dye use to the risk of developing several types of malignancies.
Saitta, Peter; Cook, Christopher E.; Messina, Jane L.; Brancaccio, Ronald; Wu, Benedict C.; Grekin, Steven K.; Holland, Jean
A patient started on 8 mg lornoxicam twice daily for pain in the hips developed acute-onset scalp hair loss. History and clinical examination revealed no evident abnormalities. Temporal association of the onset of hair loss with the use of lornoxicam, inability to explain hair loss by alternate causes, possibility of hair loss with lornoxicam and resolution on dechallenge placed this reaction as a probable adverse reaction to lornoxicam. PMID:24029201
Keny, M S; Ghodge, R R; Bandekar, S M
Epidermal development and cyclic hair follicle regeneration are governed by well-balanced programs of gene activation and silencing. Recent researches demonstrated that the expression profiles of miRNA showed tissue-specific expression patterns in the epidermis and hair follicles and stage-specific in cyclical development of hair follicles. Furthermore, a large number of miRNAs are involved in the development of epidermis and hair follicles, pigmentation, and the cyclical development of hair follicles. miRNAs in different cell types formed a comprehensive, multi-level network system through interaction with signal pathway and regulation factors. This review summarizes the available progress on how miRNAs are involved in the control of epidermal homeostasis and hair follicle development to enrich the research of gene regulatory networks and contribute to disease treatment and molecular breeding. PMID:24400482
Cai, Ting; Liu, Zhi-Hong; Wang, Zhi-Xin; Zhao, Meng; Ju, Hong-Li; Li, Jin-Quan
Nineteen patients associated with sexual anomalies were studied for chromosome abnormalities. Five cases (26.3 per cent) were found to be chromosomally abnormal. They were one case of mixed gonadal dysgenesis with an XY/XO mosaicism, two cases of Klinefel...
C. C. Lin K. S. W. Kim P. Y. Wei
Ectodysplasin (Eda), a member of the tumor necrosis factor (Tnf) family, regulates skin appendage morphogenesis via its receptor Edar and transcription factor NF-?B. In humans, inactivating mutations in the Eda pathway components lead to hypohidrotic ectodermal dysplasia (HED), a syndrome characterized by sparse hair, tooth abnormalities, and defects in several cutaneous glands. A corresponding phenotype is observed in Eda-null mice,
Sylvie Lefebvre; Ingrid Fliniaux; Pascal Schneider; Marja L Mikkola
Endocrine changes supervening after parturition and menopause participate in the control of sebum production and hair growth modulation. The ensuing conditions include some peculiar aspects of hair loss (effluvium), alopecia, and facial hirsutism. The hair cycling is of major clinical relevance because most hair growth disorders result from disturbances in this chronobiological feature. Of note, any correlation between a biologic abnormality and hair cycling disturbance does not prove a relationship of causality. The proportion of postmenopausal women is rising in the overall population. Therefore, the prevalence of these hair follicle disturbances is globally on the rise. Current therapies aim at correcting the underlying hormonal imbalances, and at improving the overall cosmetic appearance. However, in absence of pathogenic diagnosis and causality criteria, chances are low that a treatment given by the whims of fate will adequately control hair effluvium. The risk and frequency of therapeutic inertia are further increased. When the hair loss is not controlled and/or compensated by growth of new hairs, several clinical aspects of alopecia inexorably develop. Currently, there is little evidence supporting any specific treatment for these endocrine hair disorders in post-partum and postmenopausal women. Current hair treatment strategies are symptomatic and nonspecific so current researchers aim at developing new, targeted methods.
Pierard-Franchimont, Claudine; Pierard, Gerald E.
Although, of no vital value, hair plays a significant role in expressing any person's psychosocial status. Many cosmetic and styling methods are available for hair. This study aimed to examine the microscopic changes in women with hair coloring, hair waving, or hair ironing in comparison with normal controls. In a cross-sectional study, 154 Iranian women were recruited and categorized in 4 groups: controls (n = 35) who had not dyed, waved or ironed their hair within the last 6 months; dyed-hair group (n = 49) who had dyed their hair using standard chemical hair colors at least three times within the last 6 months; waved-hair group (n = 35) who had frizzled their hair within the last 6 months and ironed-hair group (n = 35) who had ironed their hair at least 3 times a weak using a temperature more than 30 degrees C within the last 6 months. Hair samples of all four groups were examined microscopically, and the results were compared with the controls. The rate of abnormal findings was 17.1% in the controls, 53.1% in the dyed-hair group, 45.7% in the waved-hair group, and 54.3% in the ironed-hair group. Abnormal findings were significantly more frequent in the last three groups comparing with the controls (p < 0.05). Trichorrhexis was 17.1, 34.7, 40 and 11.4%; kinking was 0, 2, 2.9 and 25.7%; pseudo pili-annulati was 0, 6.1, 0 and 17.1%; trichonodosis was 0, 6.1, 0 and 0%; tracheoschises was 0, 2, 2.9 and 0% and trichoptilosis was 0, 2, 0 and 0% in the mentioned groups, respectively. Based on the results of the present study, hair coloring, waving and ironing all can induce abnormalities in the hair in comparison with the hairs of nonusers. PMID:24506020
Talghini, Shahla; Ranjkesh, Mohammadreza
Human hair follicles can be dissected out of scalp skin and cultured in vitro in defined growth medium. Hair follicle organ cultures have previously been used to investigate the molecular and cellular mechanisms through which various factors regulate the maintenance and cycling of adult hair follicles. In this issue, Samuelov et al. transfected organ-cultured human hair follicles with siRNA nucleotides and suppressed the expression of the endogenous P-cadherin gene in follicular keratinocytes. Knocking down the expression of P-cadherin in hair follicles in vitro recapitulated the hair follicle phenotype observed in patients with hypotrichosis with juvenile macular dystrophy (HJMD) and enabled the authors to establish a cause-effect relationship between loss of P-cadherin and suppression of the canonical Wnt signaling pathway and upregulation of TGF?2 during development of the hair abnormalities observed in HJMD patients. PMID:22971919
Chen, Jiang; Roop, Dennis R
Root hairs project from the surface of the root to aid nutrient and water uptake and to anchor the plant in the soil. Their formation involves the precise control of cell fate and localized cell growth. We are now beginning to unravel the complexities of the molecular interactions that underlie this developmental regulation. In addition, after years of speculation, nutrient transport by root hairs has been demonstrated clearly at the physiological and molecular level, with evidence for root hairs being intense sites of H(+)-ATPase activity and involved in the uptake of Ca(2+), K(+), NH(4)(+), NO(3)(-), Mn(2+), Zn(2+), Cl(-) and H(2)PO(4)(-).
Gilroy, S.; Jones, D. L.
We have previously shown that the ubiquitously expressed lysosomal cysteine protease, cathepsin L (CTSL), is essential for skin and hair follicle homeostasis. Here we examine the effect of CTSL deficiency on hair follicle development and cycling in ctsl?/? mice by light and electron microscopy, Ki67/terminal dUTP nick-end labeling, and trichohyalin immunofluorescence. Hair follicle morphogenesis in ctsl?/? mice was associated with several abnormalities. Defective terminal differentiation of keratinocytes occurred during the formation of the hair canal, resulting in disruption of hair shaft outgrowth. Both proliferation and apoptosis levels in keratinocytes and melanocytes were higher in ctsl?/? than in ctsl+/+ hair follicles. The development of the hair follicle pigmentary unit was disrupted by vacuolation of differentiating melanocytes. Hair cycling was also abnormal in ctsl?/? mice. Final stages of hair follicle morphogenesis and the induction of hair follicle cycling were retarded. Thereafter, these follicles exhibited a truncated resting phase (telogen) and a premature entry into the first growth phase. Further abnormalities of telogen development included the defective anchoring of club hairs in the skin, which resulted in their abnormal shedding. Melanocyte vacuolation was again apparent during the hair cycle-associated reconstruction of the hair pigmentary unit. A hallmark of these ctsl?/? mice was the severe disruption in the exiting of hair shafts to the skin surface. This was mostly because of a failure of the inner root sheath (keratinocyte layer next to the hair shaft) to fully desquamate. These changes resulted in a massive dilation of the hair canal and the abnormal routing of sebaceous gland products to the skin surface. In summary, this study suggests novel roles for cathepsin proteases in skin, hair, and pigment biology. Principal target tissues that may contain protein substrate(s) for this cysteine protease include the developing hair cone, inner root sheath, anchoring apparatus of the telogen club, and organelles of lysosomal origin (eg, melanosomes).
Tobin, Desmond J.; Foitzik, Kerstin; Reinheckel, Thomas; Mecklenburg, Lars; Botchkarev, Vladimir A.; Peters, Christoph; Paus, Ralf
Cadherin 23 is required for normal development of the sensory hair bundle, and recent evidence suggests it is a component of the tip links, filamentous structures thought to gate the hair cells' mechano-electrical transducer channels. Antibodies against unique peptide epitopes were used to study the properties of cadherin 23 and its spatio-temporal expression patterns in developing cochlear hair cells. In
Vincent Michel; Richard J. Goodyear; Dominique Weil; Walter Marcotti; Isabelle Perfettini; Uwe Wolfrum; Corné J. Kros; Guy P. Richardson; Christine Petit
Activating mutations in the KRAS oncogene are associated with three related human syndromes, which vary in hair and skin phenotypes depending on the involved allele. How variations in RAS signals are interpreted during hair and skin development is unknown. In this study, we investigated the developmental and transcriptional response of skin and hair to changes in RAS activity, using mouse genetic models and microarray analysis. While activation of Kras (KrasG12D) in the skin had strong effects on hair growth and hair shape, steady state changes in downstream RAS/MAPK effectors were subtle and detected only by transcriptional responses. To model the transcriptional response of multiple developmental pathways to active RAS, the effects of growth factor stimulation were studied in skin explants. Here FGF acutely suppressed Shh transcription within 90 minutes but had significantly less effect on Eda, WNT, Notch or BMP pathways. Furthermore, in vivo Fgfr2 loss-of-function in the ectoderm caused derepression of Shh, revealing a role for FGF in Shh regulation in the hair follicle. These studies define both dosage sensitive effects of RAS signaling on hair morphogenesis and reveal acute mechanisms for fine-tuning Shh levels in the hair follicle.
Mukhopadhyay, Anandaroop; Krishnaswami, Suguna Rani; Cowing-Zitron, Christopher; Hung, Nai-Jung; Reilly-Rhoten, Heather; Burns, Julianne; Yu, Benjamin D.
Activating mutations in the KRAS oncogene are associated with three related human syndromes, which vary in hair and skin phenotypes depending on the involved allele. How variations in RAS signals are interpreted during hair and skin development is unknown. In this study, we investigated the developmental and transcriptional response of skin and hair to changes in RAS activity, using mouse genetic models and microarray analysis. While activation of Kras (Kras(G12D)) in the skin had strong effects on hair growth and hair shape, steady state changes in downstream RAS/MAPK effectors were subtle and detected only by transcriptional responses. To model the transcriptional response of multiple developmental pathways to active RAS, the effects of growth factor stimulation were studied in skin explants. Here FGF acutely suppressed Shh transcription within 90 min but had significantly less effect on Eda, WNT, Notch or BMP pathways. Furthermore, in vivo Fgfr2 loss-of-function in the ectoderm caused derepression of Shh, revealing a role for FGF in Shh regulation in the hair follicle. These studies define both dosage sensitive effects of RAS signaling on hair morphogenesis and reveal acute mechanisms for fine-tuning Shh levels in the hair follicle. PMID:23123965
Mukhopadhyay, Anandaroop; Krishnaswami, Suguna Rani; Cowing-Zitron, Christopher; Hung, Nai-Jung; Reilly-Rhoten, Heather; Burns, Julianne; Yu, Benjamin D
Roots hairs are cylindrical extensions of root epidermal cells that are important for acquisition of nutrients, microbe interactions, and plant anchorage. The molecular mechanisms involved in the specification, differentiation, and physiology of root hairs in Arabidopsis are reviewed here. Root hair specification in Arabidopsis is determined by position-dependent signaling and molecular feedback loops causing differential accumulation of a WD-bHLH-Myb transcriptional complex. The initiation of root hairs is dependent on the RHD6 bHLH gene family and auxin to define the site of outgrowth. Root hair elongation relies on polarized cell expansion at the growing tip, which involves multiple integrated processes including cell secretion, endomembrane trafficking, cytoskeletal organization, and cell wall modifications. The study of root hair biology in Arabidopsis has provided a model cell type for insights into many aspects of plant development and cell biology.
Grierson, Claire; Nielsen, Erik; Ketelaarc, Tijs; Schiefelbein, John
BACKGROUND: Chromosomal abnormalities are an important cause of spontaneous abortion and recurrent mis- carriage (RM). Therefore, we have analysed the incidence of chromosomal abnormalities and embryo development in patients with RM. METHODS: Preimplantation genetic diagnosis (PGD) was performed on 71 couples with RM and 28 couples undergoing PGD for sex-linked diseases (control group). Chromosomes 13, 16, 18, 21, 22, X
C. Rubio; C. Simon; F. Vidal; L. Rodrigo; T. Pehlivan; J. Remohi; A. Pellicer
Specialized plant cells form cell walls with distinct composition and properties pertinent to their function. Leaf trichomes in Arabidopsis form thick cell walls that support the upright growth of these large cells and, curiously, have strong light-reflective properties. To understand the process of trichome cell-wall maturation and the molecular origins of this optical property, mutants affected in trichome light reflection were isolated and characterized. It was found that GLASSY HAIR (GLH) genes are required for the formation of surface papillae structures at late stages of trichome development. Trichomes in these mutants appeared transparent due to unobstructed light transmission. Genetic analysis of the isolated mutants revealed seven different gene loci. Two--TRICHOME BIREFRINGENCE (TBR) and NOK (Noeck)--have been reported previously to have the glassy trichome mutant phenotype. The other five glh mutants were analysed for cell-wall-related phenotypes. A significant reduction was found in cellulose content in glh2 and glh4 mutant trichomes. In addition to the glassy trichome phenotype, the glh6 mutants showed defects in leaf cuticular wax, and glh6 was found to represent a new allele of the eceriferum 10 (cer10) mutation. Trichomes of the glh1 and glh3 mutants did not show any other phenotypes beside reduced papillae formation. These data suggest that the GLH1 and GLH3 genes may have specific functions in trichome papillae formation, whereas GLH2, GLH4, and GLH6 genes are also involved in deposition of other cell-wall components. PMID:24014871
Suo, Bangxia; Seifert, Stephanie; Kirik, Viktor
Specialized plant cells form cell walls with distinct composition and properties pertinent to their function. Leaf trichomes in Arabidopsis form thick cell walls that support the upright growth of these large cells and, curiously, have strong light-reflective properties. To understand the process of trichome cell-wall maturation and the molecular origins of this optical property, mutants affected in trichome light reflection were isolated and characterized. It was found that GLASSY HAIR (GLH) genes are required for the formation of surface papillae structures at late stages of trichome development. Trichomes in these mutants appeared transparent due to unobstructed light transmission. Genetic analysis of the isolated mutants revealed seven different gene loci. Two—TRICHOME BIREFRINGENCE (TBR) and NOK (Noeck)—have been reported previously to have the glassy trichome mutant phenotype. The other five glh mutants were analysed for cell-wall-related phenotypes. A significant reduction was found in cellulose content in glh2 and glh4 mutant trichomes. In addition to the glassy trichome phenotype, the glh6 mutants showed defects in leaf cuticular wax, and glh6 was found to represent a new allele of the eceriferum 10 (cer10) mutation. Trichomes of the glh1 and glh3 mutants did not show any other phenotypes beside reduced papillae formation. These data suggest that the GLH1 and GLH3 genes may have specific functions in trichome papillae formation, whereas GLH2, GLH4, and GLH6 genes are also involved in deposition of other cell-wall components.
Our laboratory discovered nestin-expressing hair follicle stem cells and demonstrated their pluripotency. We have shown that nestin-positive and K15-negative multipotent hair follicle stem cells are located above the hair follicle bulge, and we termed these cells hair follicle pluripotent stem (hfPS) cells. We have previously shown that hair follicle stem cells can regenerate peripheral nerve and spinal cord. In the present study, we describe the embryonic development of the hair follicle stem cell area (hfPSCA), which is located above the bulge and below the sebaceous glands in the adult mouse. At embryonic day 16.5 (E16.5) of nestindriven GFP (ND-GFP) transgenic mice, which express nestin in hfPS cells, the ND-GFP hair follicle stem cells are located in mesenchymal condensates. At postnatal day 0 (P0), the ND-GFP-expressing cells are migrating to the upper part of the hair follicle from the dermal papilla. At P3, keratin 15 (K15)-positive cells, derived from ND-GFP dermal papilla cells, are located in the outer-root sheath and basal layer of the epidermis. By P10, the ND-GFP have formed the K15-positive outer-root sheath as well as the ND-GFP hfPSA. These results suggest that ND-GFP hfPS cells in the dermal papilla form nestin-expressing hair follicle stem cells in the first hair cycle. These observations provide new insight into the origins of hfPS cells and the hfPSCA. PMID:20683701
Amoh, Yasuyuki; Li, Lingna; Katsuoka, Kensei; Hoffman, Robert M
In hair follicle development, a placode-derived signal is believed to induce formation of the dermal condensation, an essential component of ectodermal organs. However, the identity of this signal is unknown. Furthermore, although induction and patterning of hair follicles are intimately linked, it is not known whether the mesenchymal condensation is necessary for inducing the initial epithelial pattern. Here, we show that fibroblast growth factor 20 (Fgf20) is expressed in hair placodes and is induced by and functions downstream from epithelial ectodysplasin (Eda)/Edar and Wnt/?-Catenin signaling to initiate formation of the underlying dermal condensation. Fgf20 governs formation of primary and secondary dermal condensations in developing hair follicles and subsequent formation of guard, awl, and auchene hairs. Although primary dermal condensations are absent in Fgf20 mutant mice, a regular array of hair placodes is formed, demonstrating that the epithelial patterning process is independent of known histological and molecular markers of underlying mesenchymal patterns during the initial stages of hair follicle development. PMID:23431057
Huh, Sung-Ho; Närhi, Katja; Lindfors, Päivi H; Häärä, Otso; Yang, Lu; Ornitz, David M; Mikkola, Marja L
Light microscopy of the hair forms an important bedside clinical tool for the diagnosis of various disorders affecting the hair. Hair abnormalities can be seen in the primary diseases affecting the hair or as a secondary involvement of hair in diseases affecting the scalp. Hair abnormalities also form a part of various genodermatoses and syndromes. In this review, we have briefly highlighted the light microscopic appearance of various infectious and non-infectious conditions affecting the hair.
Adya, Keshavmurthy A; Inamadar, Arun C; Palit, Aparna; Shivanna, Ragunatha; Deshmukh, Niranjan S
Sensory hair bundles in the inner ear are composed of stereocilia that can be interconnected by a variety of different link types, including tip links, horizontal top connectors, shaft connectors, and ankle links. The ankle link antigen is an epitope specifically associated with ankle links and the calycal processes of photoreceptors in chicks. Mass spectrometry and immunoblotting were used to identify this antigen as the avian ortholog of the very large G-protein-coupled receptor VLGR1, the product of the Usher syndrome USH2C (Mass1) locus. Like ankle links, Vlgr1 is expressed transiently around the base of developing hair bundles in mice. Ankle links fail to form in the cochleae of mice carrying a targeted mutation in Vlgr1 (Vlgr1/del7TM), and the bundles become disorganized just after birth. FM1-43 [N-(3-triethylammonium)propyl)-4-(4-(dibutylamino)styryl) pyridinium dibromide] dye loading and whole-cell recordings indicate mechanotransduction is impaired in cochlear, but not vestibular, hair cells of early postnatal Vlgr1/del7TM mutant mice. Auditory brainstem recordings and distortion product measurements indicate that these mice are severely deaf by the third week of life. Hair cells from the basal half of the cochlea are lost in 2-month-old Vlgr1/del7TM mice, and retinal function is mildly abnormal in aged mutants. Our results indicate that Vlgr1 is required for formation of the ankle link complex and the normal development of cochlear hair bundles.
McGee, JoAnn; Goodyear, Richard J.; McMillan, D. Randy; Stauffer, Eric A.; Holt, Jeffrey R.; Locke, Kirsten G.; Birch, David G.; Legan, P. Kevin; White, Perrin C.; Walsh, Edward J.; Richardson, Guy P.
Background: The skin is responsible for forming a variety of epidermal structures that differ amongst vertebrates. In each case the specific structure (for example scale, feather or hair) arises from an epidermal placode as a result of epithelial–mesenchymal interactions with the underlying dermal mesenchyme. Expression of members of the Wnt, Hedgehog and bone morphogenetic protein families (Wnt10b, Sonic hedgehog (Shh)
B. St-Jacques; H. R. Dassule; I. Karavanova; V. A. Botchkarev; J. Li; P. S. Danielian; J. A. McMahon; P. M. Lewis; R. Paus; A. P. McMahon
The cell surface marker CD34 marks mouse hair follicle bulge cells, which have attributes of stem cells, including quiescence and multipotency. Using a CD34 knockout (KO) mouse, we tested the hypothesis that CD34 may participate in tumor development in mice because hair follicle stem cells are thought to be a major target of carcinogens in the two-stage model of mouse
Carol S. Trempus; Rebecca J. Morris; Matthew Ehinger; Amy Elmore; Carl D. Bortner; Mayumi Ito; George Cotsarelis; Joanne G. W. Nijhof; John Peckham; Norris Flagler; Grace Kissling; Margaret M. Humble; Leon C. King; Linda D. Adams; Dhimant Desai; Shantu Amin; Raymond W. Tennant
MicroRNAs (miRNAs) are an emerging class of regulators that control post-transcriptional processes, and could be potential targets for drug in pathology and potential sites of phenotypic regulation. Although some functions of miRNAs have been known, the regulatory mechanism of miRNAs in skin and hair follicle development remains unclear. High throughput sequencing provides more accurate and rapid method for identification of miRNAs. It has been found that some miRNAs affect the cell differentiation and proliferation of skin and hair follicles, and their target genes play important roles in the periodic growth of hair follicles. In this review, we summarize the recent achievements of the regulatory mechanism of miRNAs in the skin follicles and provide useful clues for further study on miRNA regulation in hair follicle growth of cashmere goat. PMID:25076029
Zhang, Lu; Zhang, Yanjun; Su, Rui; Wang, Ruijun; Li, Jinquan
By using a forward genetic approach, a formin homology 1 gene (OsFH1) was identified as a critical regulator of rice root hair development. The phenotypic effect of OsFH1 on root hair development was verified by using three independent mutants, one point mutation and two T-DNA insertions. The study showed that OsFH1 is required for the elongation of root-hairs. However, Osfh1 exhibited growth defect of root hairs only when roots were grown submerged in solution. To understand how OsFH1 impinges on plant responses to root submergence, the growth responses of Osfh1 root hairs to anoxia, carbohydrate supplementation and exogenous hormones (auxin and ethylene) and nutrients (Fe and Pi) were examined. However, none of these treatments rescued the growth defects of Osfhl1 root hairs. This study demonstrates that OsFH1 could be involved in preventing submergence-induced inhibition of root hair growth.
Huang, Jin; Liu, Jingmiao; Han, Chang-deok
This review presents an overview of human cortical malformation based on the insights gained from examination of human fetal brains. Examination at early stages of fetal brain development allows the identification of the specific pathways which are disrupted in human cortical malformation. Detailed examination of human fetal brains in parallel with studies of genetics and animal models is leading to new concepts of cortical malformations. Here we review a range of human cortical malformations based on a simple classification according to the developmental process thought to be disrupted: neuroblast proliferation, undermigration, overmigration, cortical maturation and destructive lesions. A single case example of a dated intrauterine injury illustrates the spectrum of malformations which may result at a single period in development. The recommended methods of examination of human fetal brain are described together with some of their pitfalls. Detailed neuropathological observations indicate the need for caution in the classification of malformations; radiological findings and pathology of the mature brain do not reflect the specific disruptive pathways of cortical malformations. While many insults may lead to the same pattern of malformation, a single insult can lead to multiple patterns of malformation. Our detailed studies of the human fetal brain suggest that the interface between the meninges and the radial glial end feet may be an intriguing new focus of interest in understanding cortical development.
Squier, Waney; Jansen, Anna
Signal transduction of the plant hormone auxin centres on the regulation of the abundance of members of the Aux/IAA family of transcriptional regulators, of which there are 29 in Arabidopsis. Auxin can influence Aux/IAA abundance by promoting the transcription of Aux/IAA genes and by reducing the half-life of Aux/IAA proteins. Stabilising mutations, which render Aux/IAA proteins resistant to auxin-mediated degradation, confer a wide range of phenotypes consistent with disruptions in auxin response. Interestingly, similar mutations in different family members can confer opposite phenotypic effects. To understand the molecular basis for this functional specificity in the Aux/IAA family, we have studied a pair of Aux/IAAs, which have contrasting roles in root hair development. We have found that stabilising mutations in AXR3/IAA17 blocks root hair initiation and elongation, whereas similar mutations in SHY2/IAA3 result in early initiation of root hair development and prolonged hair elongation, giving longer root hairs. The phenotypes resulting from double mutant combinations, the transient induction of expression of the proteins, and the pattern of transcription of the cognate genes suggest that root hair initiation is controlled by the relative abundance of SHY2 and AXR3 in a cell. These results suggest a general model for auxin signalling in which the modulation of the relative abundance of different Aux/IAA proteins can determine which down-stream responses are induced. PMID:14534134
Knox, Kirsten; Grierson, Claire S; Leyser, Ottoline
Visual examination of roots from 12,000 mutagenized Arabidopsis seedlings has led to the identification of more'. than 40 mutants impaired in root hair morphogenesis. Mutants from four phenotypic classes have been characterized in detail, and genetic tests show that these result from single nuclear recessive mutations in four different genes designated RHD1, RHDP, RHD3, and RHD4. The phenotypic analysis of
John W. Schiefelbein; Chris Somenrille
Epicardium and epicardium-derived cells have been shown to be necessary for myocardial differentiation. To elucidate the function of podoplanin in epicardial development and myocardial differentiation, we analyzed podoplanin knockout mouse embryos between embryonic day (E) 9.5 and E15.5 using immunohistochemical differentiation markers, morphometry, and three-dimensional reconstructions. Podoplanin null mice have an increased embryonic lethality, possibly of cardiac origin. Our study reveals impairment in the development of the proepicardial organ, epicardial adhesion, and spreading and migration of the epicardium-derived cells. Mutant embryos show a hypoplastic and perforated compact and septal myocardium, hypoplastic atrioventricular cushions resulting in atrioventricular valve abnormalities, as well as coronary artery abnormalities. The epicardial pathology is correlated with reduced epithelial-mesenchymal transformation caused by up-regulation of E-cadherin, normally down-regulated by podoplanin. Our results demonstrate a role for podoplanin in normal cardiac development based on epicardial-myocardial interaction. Abnormal epicardial differentiation and reduced epithelial-mesenchymal transformation result in deficient epicardium-derived cells leading to myocardial pathology and cardiac anomalies. PMID:18265012
Mahtab, Edris A F; Wijffels, Maurits C E F; Van Den Akker, Nynke M S; Hahurij, Nathan D; Lie-Venema, Heleen; Wisse, Lambertus J; Deruiter, Marco C; Uhrin, Pavel; Zaujec, Jan; Binder, Bernd R; Schalij, Martin J; Poelmann, Robert E; Gittenberger-De Groot, Adriana C
The cell surface marker CD34 marks mouse hair follicle bulge cells, which have attributes of stem cells, including quiescence and multipotency. Using a CD34 knockout (KO) mouse, we tested the hypothesis that CD34 may participate in tumor development in mice because hair follicle stem cells are thought to be a major target of carcinogens in the two-stage model of mouse skin carcinogenesis. Following initiation with 200 nmol 7,12-dimethylbenz(a)anthracene (DMBA), mice were promoted with 12-O-tetradecanoylphorbol-13-acetate (TPA) for 20 weeks. Under these conditions, CD34KO mice failed to develop papillomas. Increasing the initiating dose of DMBA to 400 nmol resulted in tumor development in the CD34KO mice, albeit with an increased latency and lower tumor yield compared with the wild-type (WT) strain. DNA adduct analysis of keratinocytes from DMBA-initiated CD34KO mice revealed that DMBA was metabolically activated into carcinogenic diol epoxides at both 200 and 400 nmol. Chronic exposure to TPA revealed that CD34KO skin developed and sustained epidermal hyperplasia. However, CD34KO hair follicles typically remained in telogen rather than transitioning into anagen growth, confirmed by retention of bromodeoxyuridine-labeled bulge stem cells within the hair follicle. Unique localization of the hair follicle progenitor cell marker MTS24 was found in interfollicular basal cells in TPA-treated WT mice, whereas staining remained restricted to the hair follicles of CD34KO mice, suggesting that progenitor cells migrate into epidermis differently between strains. These data show that CD34 is required for TPA-induced hair follicle stem cell activation and tumor formation in mice.
Trempus, Carol S.; Morris, Rebecca J.; Ehinger, Matthew; Elmore, Amy; Bortner, Carl D.; Ito, Mayumi; Cotsarelis, George; Nijhof, Joanne G.W.; Peckham, John; Flagler, Norris; Kissling, Grace; Humble, Margaret M.; King, Leon C.; Adams, Linda D.; Desai, Dhimant; Amin, Shantu; Tennant, Raymond W.
Gross motor development (supine, prone, rolling, sitting, crawling, walking) and movement abnormalities were examined in the home videos of infants later diagnosed with autism (regression and no regression subgroups), developmental delays (DD), or typical development. Group differences in maturity were found for walking, prone, and supine, with…
Ozonoff, Sally; Young, Gregory S.; Goldring, Stacy; Greiss-Hess, Laura; Herrera, Adriana M.; Steele, Joel; Macari, Suzanne; Hepburn, Susan; Rogers, Sally J.
Clinical and laboratory methods were developed to detect motor abnormalities in patients with Huntington Disease. For clinical evaluation a quantitated neurological examination was used which factor analyzed into 2 scales: a chorea scale (a measure of involuntary movement) and a motor impairment scale (a measure of abnormalities of voluntary movement). Mechanized methods of measuring involuntary movement (accelerometer) and voluntary movement (reaction time, tapping speed, and movement time) were also developed. The motor abnormalities detected on the clinical and mechanical tests were not specific to HD but were also present in persons at 50% risk for HD and in patients with a variety of neurological disorders. The mechanized tests may be useful for screening for motor disorders in the population: they are non-specific, portable and do not require the services of an experienced clinician. PMID:6230541
Folstein, S E; Jensen, B; Leigh, R J; Folstein, M F
Analysis of nicotine and cotinine in human hair can provide information on nicotine intake and exposure to environmental tobacco smoke over a long period of time. Nonetheless, to better assess the usefulness of hair analysis to determine smoking habits or exposures, all procedures have to be standardized. Various solvents were tested as washing solvents to eliminate external contamination from nicotine.
Simona Pichini; Ilaria Altieri; Manuela Pellegrini; Roberta Pacifici; Piergiorgio Zuccaro
Numerous strains of mice with defined mutations display pronounced abnormalities of hair follicle cycling, even in the absence of overt alterations of the skin and hair phenotype; however, in order to recognize even subtle, hair cycle-related abnormalities, it is critically important to be able to determine accurately and classify the major stages of the normal murine hair cycle. In this
Sven Müller-Röver; Bori Handjiski; Carina van der Veen; Stefan Eichmüller; Kerstin Foitzik; Ian A. McKay; Kurt S. Stenn; Ralf Paus
Reactive oxygen species (ROS) have been shown to play key roles in cellular decision making and signal integration in multicellular organisms. In roots, ROS levels are managed by the action of peroxidases and NAPDH oxidases, resulting in a distinct spatial distribution of hydrogen peroxide (H?O?) and superoxide (O?(-)) that is critical for the balance between cell proliferation and differentiation. In addition, ROS is required for the determination of the cell shape of root hairs. Mutations in the Mediator subunit MED25/PFT1 result in compromised root hair development, due to altered expression of a suite of H?O?-producing class III peroxidases. pft1-1 mutants form shorter root hairs than wild-type plants. Analysis of pft1-1 cross-sections revealed that also root hair initiation is compromised, probably by impeding local cell wall loosening. It is suggested that ROS homeostasis is critical throughout the development of root hairs, controlling various processes via PFT1-regulated transcription of genes encoding redox-active enzymes. PMID:23455023
Sundaravelpandian, Kalaipandian; Chandrika, Nulu; Tsai, Yi-Hsiu; Schmidt, Wolfgang
Cystic fibrosis (CF) is a hereditary condition that affects cAMP-regulated chloride channels in epithelial tissues due to a defect in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Recently, a transgenic CF mouse model was developed at UNC that exhibits no CFTR expression. Interestingly, the CF mouse demonstrates abnormal incisor enamel. Therefore, the purpose of this investigation was to characterize
J. T. Wright; C. L. Kiefer; K. I. Hall; B. R. Grubb
The most frequent cause of congenital hypothyroidism is thyroid dysgenesis. Thyroid dysgenesis summarizes a spectrum of developmental abnormalities of the embryonic thyroid ranging from complete absence of the thyroid gland (athyreosis), to a normally located but too small thyroid (hypoplasia), or an abnormally located thyroid gland (ectopy). Although considered a sporadic disease, distinct genetic forms of isolated or syndromic thyroid dysgenesis have been described in recent years. However, genetics of thyroid dysgenesis (TD) are mostly not following simple Mendelian patterns, and beside monogenic, multigenic and epigenetic mechanisms need to be considered. The review will highlight the molecular mechanisms of thyroid organogenesis, clinical and genetic features of the different monogenetic forms of thyroid dysgenesis, the aspects relevant for diagnosis and counseling of affected families and current research strategies to get more insight into the non-Medelian mechanisms of normal and abnormal thyroid development. PMID:24629857
Precise frequency discrimination is a hallmark of auditory function in birds and mammals and is required for distinguishing similar sounding words, like 'bat,' 'cat' and 'hat.' In the cochlea, tuning and spectral separation result from longitudinal differences in basilar membrane stiffness and numerous individual gradations in sensory hair cell phenotypes, but it is unknown what patterns the phenotypes. Here we used RNA-seq to compare transcriptomes from proximal, middle and distal regions of the embryonic chicken cochlea, and found opposing longitudinal gradients of expression for retinoic acid (RA)-synthesizing and degrading enzymes. In vitro experiments showed that RA is necessary and sufficient to induce the development of distal-like hair cell phenotypes and promotes expression of the actin-crosslinking proteins, Espin and Fscn2. These and other findings highlight a role for RA signalling in patterning the development of a longitudinal gradient of frequency-tuned hair cell phenotypes in the cochlea. PMID:24845860
Thiede, Benjamin R; Mann, Zoë F; Chang, Weise; Ku, Yuan-Chieh; Son, Yena K; Lovett, Michael; Kelley, Matthew W; Corwin, Jeffrey T
The erbB-2 proto-oncogene belongs to a receptor tyrosine kinase family that includes the epidermal growth factor receptor, erbB-2, erbB-3, and erbB-4. erbB-2 is expressed in basal cells of the squamous epithelia and the outer root sheath of the hair follicles, but its function in epidermal development has not been well studied. To investigate its role in the skin, we created transgenic mice harboring an activated erbB-2 oncogene under the control of the human keratin 14 promoter. The keratin 14 promoter directed its expression to cells in which erbB-2 is normally expressed, whereas the activated receptor gene ensured increased signaling. All transgenic founder mice exhibited extensive and striking skin phenotype, including epidermal hyperplasia, preneoplasia, papilloma, hyperkeratosis, and dyskeratosis. The majority of the hair follicles were replaced by bizarre hyperproliferative intradermal squamous invaginations, whereas the rest of the follicles exhibited severe hyperplasia and disorganization. All but one of the transgenic mice died before or shortly after birth, probably as a consequence of defects in the skin and esophagus. These observations demonstrate that the skin is sensitive to erbB-2 signaling, suggesting an important role for this receptor tyrosine kinase in epidermal growth, differentiation, and hair follicle morphogenesis. PMID:9563851
Xie, W; Wu, X; Chow, L T; Chin, E; Paterson, A J; Kudlow, J E
Hair follicle morphogenesis is initiated by a dermal signal that induces the development of placodes in the overlying epithelium. To determine whether WNT signals are required for initiation of follicular development, we ectopically expressed Dickkopf 1, a potent diffusible inhibitor of WNT action, in the skin of transgenic mice. This produced a complete failure of placode formation prior to morphological
Thomas Andl; Seshamma T. Reddy; Trivikram Gaddapara; Sarah E. Millar
Hair follicle morphogenesis requires coordination of multiple signals and communication between its epithelial and mesenchymal constituents. Cell adhesion protein platforms, which include integrins and integrin-linked kinase (ILK), are critical for hair follicle formation. However, their precise contribution to this process is poorly understood. We show that in the absence of ILK, the hair follicle matrix lineage fails to develop, likely due to abnormalities in development of apical–basal cell polarity, as well as in laminin-511 and basement membrane assembly at the tip of the hair bud. These defects also result in impaired specification of hair matrix and absence of precortex and inner sheath root cell lineages. The molecular pathways affected in ILK-deficient follicles are similar to those in the absence of epidermal integrin ?1 and include Wnt, but not sonic hedgehog, signaling. ILK-deficient hair buds also show abnormalities in the dermal papilla. Addition of exogenous laminin-511 restores morphological and molecular markers associated with hair matrix formation, indicating that ILK regulates hair bud cell polarity and functions upstream from laminin-511 assembly to regulate the developmental progression of hair follicles beyond the germ stage.
Rudkouskaya, Alena; Welch, Ian; Dagnino, Lina
Complexin I expression is dysregulated in a number of neurological diseases including schizophrenia and depression. Adult complexin 1 knockout (Cplx1?\\/?) mice are severely ataxic and show deficits in exploration and emotional reactivity. Here, we evaluated early behavioural development of Cplx1?\\/? mice. Cplx1?\\/? mice showed marked abnormalities. They develop ataxia by post-natal day 7 (P7), and by P21 show marked deficits
Dervila Glynn; Rachel J. Sizemore; A. Jennifer Morton
This review covers the relationship between chromosome abnormalities, morphological abnormalities and embryonic development. The baseline of chromosome abnormalities in human embryos produced by assisted reproduction is higher than 50%, regardless of maternal age. While aneuploidy increases with maternal age, abnormalities arising post-meiotically, such as mosaicism, chaoticism, polyploidy and haploidy, have similar incidence in all age groups (about 33%). Post-meiotic abnormalities
One of the prevailing hypotheses suggests schizophrenia as a neurodevelopmental disorder, involving dysfunction of dopaminergic and glutamatergic systems. Accumulating evidence suggests mitochondria as an additional pathological factor in schizophrenia. An attractive model to study processes related to neurodevelopment in schizophrenia is reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) and differentiating them into different neuronal lineages. iPSCs from three schizophrenia patients and from two controls were reprogrammed from hair follicle keratinocytes, because of their accessibility and common ectodermal origin with neurons. iPSCs were differentiated into Pax6(+)/Nestin(+) neural precursors and then further differentiated into ?3-Tubulin(+)/tyrosine hydroxylase(+)/DAT(+) dopaminergic neurons. In addition, iPSCs were differentiated through embryonic bodies into ?3-Tubulin(+)/Tbox brain1(+) glutamatergic neurons. Schizophrenia-derived dopaminergic cells showed severely impaired ability to differentiate, whereas glutamatergic cells were unable to maturate. Mitochondrial respiration and its sensitivity to dopamine-induced inhibition were impaired in schizophrenia-derived keratinocytes and iPSCs. Moreover, we observed dissipation of mitochondrial membrane potential (??m) and perturbations in mitochondrial network structure and connectivity in dopaminergic along the differentiation process and in glutamatergic cells. Our data unravel perturbations in neural differentiation and mitochondrial function, which may be interconnected, and of relevance to dysfunctional neurodevelopmental processes in schizophrenia. PMID:23732879
Robicsek, O; Karry, R; Petit, I; Salman-Kesner, N; Müller, F-J; Klein, E; Aberdam, D; Ben-Shachar, D
Analysis of nicotine and cotinine in human hair can provide information on nicotine intake and exposure to environmental tobacco smoke over a long period of time. Nonetheless, to better assess the usefulness of hair analysis to determine smoking habits or exposures, all procedures have to be standardized. Various solvents were tested as washing solvents to eliminate external contamination from nicotine. Dichloromethane was found effective when used for two washes prior to the extraction. Basic and acid digestion of hair followed by solid phase extraction with Extrelut-3 glass column using dichloromethane:isopropyl alcohol (9:1) as eluting mixture both gave good recoveries of nicotine and cotinine, when compared with extractions reported in the literature. The extraction method was free from substances, which could interfere in the chromatographic analysis. Furthermore, the addition of methanolic HCl to the eluting mixture prevented the loss of nicotine during the evaporation step before chromatography. Chromatography was performed using a reversed-phase column and a U.V. detection at 254 nm. Furthermore, hair treatments (dyes, permanent wave, hydrogen peroxide) caused a major decrease in the nicotine content in hair, and a smaller effect on cotinine levels. However, the effect of various treatments was not reproducible. Several attempts to produce reference materials were carried out. Nicotine and cotinine standard solutions at different concentrations were added to blank hair soaked in dimethylsulfoxide, methanol and water. PMID:9042730
Pichini, S; Altieri, I; Pellegrini, M; Pacifici, R; Zuccaro, P
Idiopathic infantile nystagmus (IIN) is a genetically heterogeneous disorder, often associated with FRMD7 mutations. As the appearance of the retina is reported to be normal based on conventional fundus photography, IIN is postulated to arise from abnormal cortical development. To determine whether the afferent visual system is involved in FRMD7 mutations, we performed in situ hybridization studies in human embryonic and fetal stages (35 days post-ovulation to 9 weeks post-conception). We show a dynamic retinal expression pattern of FRMD7 during development. We observe expression within the outer neuroblastic layer, then in the inner neuroblastic layer and at 9 weeks post-conception a bilaminar expression pattern. Expression was also noted within the developing optic stalk and optic disk. We identified a large cohort of IIN patients (n = 100), and performed sequence analysis which revealed 45 patients with FRMD7 mutations. Patients with FRMD7 mutations underwent detailed retinal imaging studies using ultrahigh-resolution optical coherence tomography. The tomograms were compared with a control cohort (n = 60). The foveal pit was significantly shallower in FRMD7 patients (P < 0.0001). The optic nerve head morphology was abnormal with significantly decreased optic disk area, retinal nerve fiber layer thickness, cup area and cup depth in FRMD7 patients (P < 0.0001). This study shows for the first time that abnormal afferent system development is associated with FRMD7 mutations and could be an important etiological factor in the development of nystagmus.
Thomas, Mervyn G.; Crosier, Moira; Lindsay, Susan; Kumar, Anil; Araki, Masasuke; Leroy, Bart P.; McLean, Rebecca J.; Sheth, Viral; Maconachie, Gail; Thomas, Shery; Moore, Anthony T.; Gottlob, Irene
Idiopathic infantile nystagmus (IIN) is a genetically heterogeneous disorder, often associated with FRMD7 mutations. As the appearance of the retina is reported to be normal based on conventional fundus photography, IIN is postulated to arise from abnormal cortical development. To determine whether the afferent visual system is involved in FRMD7 mutations, we performed in situ hybridization studies in human embryonic and fetal stages (35 days post-ovulation to 9 weeks post-conception). We show a dynamic retinal expression pattern of FRMD7 during development. We observe expression within the outer neuroblastic layer, then in the inner neuroblastic layer and at 9 weeks post-conception a bilaminar expression pattern. Expression was also noted within the developing optic stalk and optic disk. We identified a large cohort of IIN patients (n = 100), and performed sequence analysis which revealed 45 patients with FRMD7 mutations. Patients with FRMD7 mutations underwent detailed retinal imaging studies using ultrahigh-resolution optical coherence tomography. The tomograms were compared with a control cohort (n = 60). The foveal pit was significantly shallower in FRMD7 patients (P < 0.0001). The optic nerve head morphology was abnormal with significantly decreased optic disk area, retinal nerve fiber layer thickness, cup area and cup depth in FRMD7 patients (P < 0.0001). This study shows for the first time that abnormal afferent system development is associated with FRMD7 mutations and could be an important etiological factor in the development of nystagmus. PMID:24688117
Thomas, Mervyn G; Crosier, Moira; Lindsay, Susan; Kumar, Anil; Araki, Masasuke; Leroy, Bart P; McLean, Rebecca J; Sheth, Viral; Maconachie, Gail; Thomas, Shery; Moore, Anthony T; Gottlob, Irene
White lupin (Lupinus albus) is a legume that is very efficient in accessing unavailable phosphorus (Pi). It develops short, densely clustered tertiary lateral roots (cluster/proteoid roots) in response to Pi limitation. In this report, we characterize two glycerophosphodiester phosphodiesterase (GPX-PDE) genes (GPX-PDE1 and GPX-PDE2) from white lupin and propose a role for these two GPX-PDEs in root hair growth and development and in a Pi stress-induced phospholipid degradation pathway in cluster roots. Both GPX-PDE1 and GPX-PDE2 are highly expressed in Pi-deficient cluster roots, particularly in root hairs, epidermal cells, and vascular bundles. Expression of both genes is a function of both Pi availability and photosynthate. GPX-PDE1 Pi deficiency-induced expression is attenuated as photosynthate is deprived, while that of GPX-PDE2 is strikingly enhanced. Yeast complementation assays and in vitro enzyme assays revealed that GPX-PDE1 shows catalytic activity with glycerophosphocholine while GPX-PDE2 shows highest activity with glycerophosphoinositol. Cell-free protein extracts from Pi-deficient cluster roots display GPX-PDE enzyme activity for both glycerophosphocholine and glycerophosphoinositol. Knockdown of expression of GPX-PDE through RNA interference resulted in impaired root hair development and density. We propose that white lupin GPX-PDE1 and GPX-PDE2 are involved in the acclimation to Pi limitation by enhancing glycerophosphodiester degradation and mediating root hair development. PMID:21464471
Cheng, Lingyun; Bucciarelli, Bruna; Liu, Junqi; Zinn, Kelly; Miller, Susan; Patton-Vogt, Jana; Allan, Deborah; Shen, Jianbo; Vance, Carroll P
Ahydroponics experiment was conducted to study the effects of nutrients (N, P, K, Ca, Mg, Fe, and Mn) deficiency on the length of primary root, the number of lateral roots, and the root hair density, length, and diameter on the primary root and lateral roots of Poncirus trifoliata seedlings. Under the deficiency of each test nutrient, root hair could generate, but was mainly concentrated on the root base and fewer on the root tip. The root hair density on lateral roots was significantly larger than that on primary root, but the root hair length was in adverse. The deficiency of each test nutrient had greater effects on the growth and development of root hairs, with the root hair density on primary root varied from 55.0 to 174.3 mm(-2). As compared with the control, Ca deficiency induced the significant increase of root hair density and length on primary root, P deficiency promoted the root hair density and length on the base and middle part of primary root and on the lateral roots significantly, Fe deficiency increased the root hair density but decreased the root hair length on the tip of primary root significantly, K deficiency significantly decreased the root hair density, length, and diameter on primary root and lateral roots, whereas Mg deficiency increased the root hair length of primary root significantly. In all treatments of nutrient deficiency, the primary root had the similar growth rate, but, with the exceptions of N and Mg deficiency, the lateral roots exhibited shedding and regeneration. PMID:24066535
Cao, Xiu; Xia, Ren-Xue; Zhang, De-Jian; Shu, Bo
Usher syndrome type IIA (USH2A), characterized by progressive photoreceptor degeneration and congenital moderate hearing loss, is the most common subtype of Usher syndrome. In this article, we show that the USH2A protein, also known as usherin, is an exceptionally large ( approximately 600-kDa) matrix protein expressed specifically in retinal photoreceptors and developing cochlear hair cells. In mammalian photoreceptors, usherin is localized to a spatially restricted membrane microdomain at the apical inner segment recess that wraps around the connecting cilia, corresponding to the periciliary ridge complex described for amphibian photoreceptors. In sensory hair cells of the cochlea, it is associated transiently with the hair bundles during postnatal development. Targeted disruption of the Ush2a gene in mice leads to progressive photoreceptor degeneration and a moderate but nonprogressive hearing impairment, mimicking the visual and hearing deficits in USH2A patients. These data suggest that usherin is required for the long-term maintenance of retinal photoreceptors and for the development of cochlear hair cells. We propose a model in which usherin in photoreceptors is tethered via its C terminus to the plasma membrane and its large extracellular domain projecting into the periciliary matrix, where they may interact with the connecting cilium to fulfill important structural or signaling roles. PMID:17360538
Liu, Xiaoqing; Bulgakov, Oleg V; Darrow, Keith N; Pawlyk, Basil; Adamian, Michael; Liberman, M Charles; Li, Tiansen
Usher syndrome type IIA (USH2A), characterized by progressive photoreceptor degeneration and congenital moderate hearing loss, is the most common subtype of Usher syndrome. In this article, we show that the USH2A protein, also known as usherin, is an exceptionally large (?600-kDa) matrix protein expressed specifically in retinal photoreceptors and developing cochlear hair cells. In mammalian photoreceptors, usherin is localized to a spatially restricted membrane microdomain at the apical inner segment recess that wraps around the connecting cilia, corresponding to the periciliary ridge complex described for amphibian photoreceptors. In sensory hair cells of the cochlea, it is associated transiently with the hair bundles during postnatal development. Targeted disruption of the Ush2a gene in mice leads to progressive photoreceptor degeneration and a moderate but nonprogressive hearing impairment, mimicking the visual and hearing deficits in USH2A patients. These data suggest that usherin is required for the long-term maintenance of retinal photoreceptors and for the development of cochlear hair cells. We propose a model in which usherin in photoreceptors is tethered via its C terminus to the plasma membrane and its large extracellular domain projecting into the periciliary matrix, where they may interact with the connecting cilium to fulfill important structural or signaling roles.
Liu, Xiaoqing; Bulgakov, Oleg V.; Darrow, Keith N.; Pawlyk, Basil; Adamian, Michael; Liberman, M. Charles; Li, Tiansen
Cadherin 23 is required for normal development of the sensory hair bundle, and recent evidence suggests it is a component of the tip links, filamentous structures thought to gate the hair cells' mechano-electrical transducer channels. Antibodies against unique peptide epitopes were used to study the properties of cadherin 23 and its spatio-temporal expression patterns in developing cochlear hair cells. In the rat, intra- and extracellular domain epitopes are readily detected in the developing hair bundle between E18 and P5, and become progressively restricted to the distal tip of the hair bundle. From P13 onwards, these epitopes are no longer detected in hair bundles, but immunoreactivity is observed in the apical, vesicle-rich, pericuticular region of the hair cell. In the P2-P3 mouse cochlea, immunogold labeling reveals cadherin 23 is associated with kinocilial links and transient lateral links located between and within stereociliary rows. At this stage, the cadherin 23 ectodomain epitope remains on the hair bundle following BAPTA or La(3+) treatment, but is lost following exposure to the protease subtilisin. In contrast, mechano-electrical transduction is abolished by BAPTA but unaffected by subtilisin. These results suggest cadherin 23 is associated with transient lateral links that have properties distinct from those of the tip-link. PMID:15882573
Michel, Vincent; Goodyear, Richard J; Weil, Dominique; Marcotti, Walter; Perfettini, Isabelle; Wolfrum, Uwe; Kros, Corné J; Richardson, Guy P; Petit, Christine
A key initial event in hair follicle morphogenesis is the localised thickening of the skin epithelium to form a placode, partitioning future hair follicle epithelium from interfollicular epidermis. Although many developmental signalling pathways are implicated in follicle morphogenesis, the role of epidermal growth factor (EGF) and keratinocyte growth factor (KGF, also known as FGF7) receptors are not defined. EGF receptor (EGFR) ligands have previously been shown to inhibit developing hair follicles; however, the underlying mechanisms have not been characterised. Here we show that receptors for EGF and KGF undergo marked downregulation in hair follicle placodes from multiple body sites, whereas the expression of endogenous ligands persist throughout hair follicle initiation. Using embryonic skin organ culture, we show that when skin from the sites of primary pelage and whisker follicle development is exposed to increased levels of two ectopic EGFR ligands (HBEGF and amphiregulin) and the FGFR2(IIIb) receptor ligand KGF, follicle formation is inhibited in a time- and dose-dependent manner. We then used downstream molecular markers and microarray profiling to provide evidence that, in response to KGF and EGF signalling, epidermal differentiation is promoted at the expense of hair follicle fate. We propose that hair follicle initiation in placodes requires downregulation of the two pathways in question, both of which are crucial for the ongoing development of the interfollicular epidermis. We have also uncovered a previously unrecognised role for KGF signalling in the formation of hair follicles in the mouse. PMID:19474150
Richardson, Gavin D; Bazzi, Hisham; Fantauzzo, Katherine A; Waters, James M; Crawford, Heather; Hynd, Phil; Christiano, Angela M; Jahoda, Colin A B
Background EpCAM (CD326) is encoded by the tacstd1 gene and expressed by a variety of normal and malignant epithelial cells and some leukocytes. Results of previous in vitro experiments suggested that EpCAM is an intercellular adhesion molecule. EpCAM has been extensively studied as a potential tumor marker and immunotherapy target, and more recent studies suggest that EpCAM expression may be characteristic of cancer stem cells. Methodology/Principal Findings To gain insights into EpCAM function in vivo, we generated EpCAM ?/? mice utilizing an embryonic stem cell line with a tacstd1 allele that had been disrupted. Gene trapping resulted in a protein comprised of the N-terminus of EpCAM encoded by 2 exons of the tacstd1 gene fused in frame to ?geo. EpCAM +/? mice were viable and fertile and exhibited no obvious abnormalities. Examination of EpCAM +/? embryos revealed that ?geo was expressed in several epithelial structures including developing ears (otocysts), eyes, branchial arches, gut, apical ectodermal ridges, lungs, pancreas, hair follicles and others. All EpCAM ?/? mice died in utero by E12.5, and were small, developmentally delayed, and displayed prominent placental abnormalities. In developing placentas, EpCAM was expressed throughout the labyrinthine layer and by spongiotrophoblasts as well. Placentas of EpCAM ?/? embryos were compact, with thin labyrinthine layers lacking prominent vascularity. Parietal trophoblast giant cells were also dramatically reduced in EpCAM ?/? placentas. Conclusion EpCAM was required for differentiation or survival of parietal trophoblast giant cells, normal development of the placental labyrinth and establishment of a competent maternal-fetal circulation. The findings in EpCAM-reporter mice suggest involvement of this molecule in development of vital organs including the gut, kidneys, pancreas, lungs, eyes, and limbs.
Nagao, Keisuke; Zhu, Jianjian; Heneghan, Mallorie B.; Hanson, Jeffrey C.; Morasso, Maria I.; Tessarollo, Lino; Mackem, Susan; Udey, Mark C.
Cashmere goat (Capra hircus) hair follicle development and cycling can be divided into three stages: anagen, catagen and telogen. To elucidate the genes involved in hair follicle development and cycling in cashmere goats, transcriptome profiling of skin was carried out by analysing samples from three hair follicle developmental stages using RNA-Seq. The RNA-Seq analysis generated 8487344, 8142514 and 7345335 clean reads in anagen, catagen and telogen stages, respectively, which provided abundant data for further analysis. A total of 1332 differentially expressed genes (DEGs) were identified, providing evidence that the development of hair follicles among the three distinct stages changed considerably. A total of 683 genes with significant differential expression were detected between anagen and catagen, 530 DEGs were identified between anagen and telogen, and 119 DEGs were identified between catagen and telogen. A large number of DEGs were predominantly related to cellular process, cell & cell part, binding, biological regulation and metabolic process among the different stages of hair follicle development. In addition, the Wnt, Shh, TGF-? and Notch signaling pathways may be involved in hair follicle development and the identified DEGs may play important roles in these signaling pathways. These results will expand our understanding of the complex molecular mechanisms of hair follicle development and cycling in cashmere goats and provide a foundation for future studies.
Geng, Rongqing; Yuan, Chao; Chen, Yulin
Cashmere goat (Capra hircus) hair follicle development and cycling can be divided into three stages: anagen, catagen and telogen. To elucidate the genes involved in hair follicle development and cycling in cashmere goats, transcriptome profiling of skin was carried out by analysing samples from three hair follicle developmental stages using RNA-Seq. The RNA-Seq analysis generated 8487344, 8142514 and 7345335 clean reads in anagen, catagen and telogen stages, respectively, which provided abundant data for further analysis. A total of 1332 differentially expressed genes (DEGs) were identified, providing evidence that the development of hair follicles among the three distinct stages changed considerably. A total of 683 genes with significant differential expression were detected between anagen and catagen, 530 DEGs were identified between anagen and telogen, and 119 DEGs were identified between catagen and telogen. A large number of DEGs were predominantly related to cellular process, cell & cell part, binding, biological regulation and metabolic process among the different stages of hair follicle development. In addition, the Wnt, Shh, TGF-? and Notch signaling pathways may be involved in hair follicle development and the identified DEGs may play important roles in these signaling pathways. These results will expand our understanding of the complex molecular mechanisms of hair follicle development and cycling in cashmere goats and provide a foundation for future studies. PMID:23638136
Geng, Rongqing; Yuan, Chao; Chen, Yulin
Hair diseases represent a significant portion of cases seen by pediatric dermatologists although hair has always been a secondary aspect in pediatricians and dermatologists training, on the erroneous basis that there is not much information extractable from it. Dermatologists are in the enviable situation of being able to study many disorders with simple diagnostic techniques. The hair is easily accessible to examination but, paradoxically, this approach is often disregarded by non-dermatologist. This paper has been written on the purpose of trying to serve in the diagnostic process of daily practice, and trying to help, for example, to distinguish between certain acquired and some genetically determined hair diseases. We will focus on all the data that can be obtained from our patients' hair and try to help on using the messages given by hair for each patient. Quite often it is extremely hard to distinguish between abnormality and normality in neonatal hair aspects. We will specially focus in the most common physiological changes that may mislead to an incorrect diagnosis. Specific treatment for those hair diseases that do have one, and basic general approach to improve the cosmetic appearance of hair, will be also be discussed for those hair disturbances that do not have a specific treatment. PMID:24566566
Moreno-Romero, J A; Grimalt, R
We have previously identified a cysteine-rich calcium binding protein S100A3 present in the cuticle of human hair fiber. In this study, we cloned a cDNA for mouse S100A3, identified its gene location, and elucidated the expression profile throughout hair follicle development. The mouse S100A3 gene was clustered with other S100 family members on chromosome 3, and specifically expressed in dorsal skin containing hair follicles. The level of S100A3 mRNA was elevated during the anagen phase of the hair growth cycle, and sharply declined from the regression phase on. In situ hybridization revealed that the S100A3 gene was prominently expressed in cuticular cells of the hair follicle, and mRNA levels were highest in the keratogenous zone over the entire cuticular layer. Expression was also observed to a lesser extent in differentiated cortical cells; however, expression was not observed in any other component of the hair follicle or dorsal tissues. Immunohistochemical analysis showed that the S100A3 protein accumulated in cuticular and cortical cells undergoing terminal differentiation. These results indicate that the S100A3 gene is exclusively expressed, and the translation product retained, in follicular cells differentiating into major components of the hair shaft. It seems likely that S100A3 plays an important role in calcium-dependent processes leading to hair shaft formation. PMID:9804353
Kizawa, K; Tsuchimoto, S; Hashimoto, K; Uchiwa, H
Objective To examine the relationship between tanning and nevus development in very-light-skinned children. Design Prospective cohort nested within a randomized controlled trial. Skin examinations in 3 consecutive years (2004, 2005, and 2006) included full-body counts of nevi, skin color and tanning measurement using colorimetry, and hair and eye color evaluation by comparison with charts. Telephone interviews of parents provided sun exposure, sun protection, and sunburn history. Setting Large managed-care organization and private pediatric offices in the Denver, Colorado, metropolitan area. Participants A total of 131 very-light-skinned white children without red hair and 444 darker-skinned white children without red hair born in Colorado in 1998. Main Outcome Measures Full-body nevus counts at ages 6 to 8 years. Results Among very-light-skinned white children, geometric mean numbers of nevi for minimally tanned children were 14.8 at age 6 years; 18.8 at age 7 years; and 22.3 at age 8 years. Mean numbers of nevi for tanned children were 21.2 at age 6 years; 27.9 at age 7 years; and 31.9 at age 8 years. Differences in nevus counts between untanned and tanned children were statistically significant at all ages (P < .05 for all comparisons). The relationship between tanning and number of nevi was independent of the child’s hair and eye color, parent-reported sun exposure, and skin phototype. Among darker-skinned white children, there was no relationship between tanning and nevi. Conclusions Very-light-skinned children who tan (based on objective measurement) develop more nevi than children who do not tan. These results suggest that light-skinned children who develop tans may be increasing their risk for developing melanoma later in life.
Aalborg, Jenny; Morelli, Joseph G.; Mokrohisky, Stefan T.; Asdigian, Nancy L.; Byers, Tim E.; Dellavalle, Robert P.; Box, Neil F.; Crane, Lori A.
The interaction between Rhizobium lipopolysaccharide (LPS) and white clover roots was examined. The Limulus lysate assay indicated that Rhizobium leguminosarum bv. trifolii (hereafter called R. trifolii) released LPS into the external root environment of slide cultures. Immunofluorescence and immunoelectron microscopy showed that purified LPS from R. trifolii 0403 bound rapidly to root hair tips and infiltrated across the root hair wall. Infection thread formation in root hairs was promoted by preinoculation treatment of roots with R. trifolii LPS at a low dose (up to 5 micrograms per plant) but inhibited at a higher dose. This biological activity of LPS was restricted to the region of the root present at the time of exposure to LPS, higher with LPS from cells in the early stationary phase than in the mid-exponential phase, incubation time dependent, incapable of reversing inhibition of infection by NO3- or NH4+, and conserved among serologically distinct LPSs from several wild-type R. trifolii strains (0403, 2S-2, and ANU843). In contrast, infections were not increased by preinoculation treatment of roots with LPSs from R. leguminosarum bv. viciae strain 300, R. meliloti 102F28, or members of the family Enterobacteriaceae. Most infection threads developed successfully in root hairs pretreated with R. trifolii LPS, whereas many infections aborted near their origins and accumulated brown deposits if pretreated with LPS from R. meliloti 102F28. LPS from R. leguminosarum 300 also caused most infection threads to abort. Other specific responses of root hairs to infection-stimulating LPS from R. trifolii included acceleration of cytoplasmic streaming and production of novel proteins. Combined gas chromatography-mass spectroscopy and proton nuclear magnetic resonance analyses indicated that biologically active LPS from R. trifolii 0403 in the early stationary phase had less fucose but more 2-O-methylfucose, quinovosamine, 3,6-dideoxy-3-(methylamino)galactose, and noncarbohydrate substituents (O-methyl, N-methyl, and acetyl groups) on glycosyl components than did inactive LPS in the mid-exponential phase. We conclude that LPS-root hair interactions trigger metabolic events that have a significant impact on successful development of infection threads in this Rhizobium-legume symbiosis. Images
Dazzo, F B; Truchet, G L; Hollingsworth, R I; Hrabak, E M; Pankratz, H S; Philip-Hollingsworth, S; Salzwedel, J L; Chapman, K; Appenzeller, L; Squartini, A
Eight proprietary genotypes of glandular-haired alfalfa, Medicago sativa L., supplied by two different companies, were compared for the degree and types of resistance to the potato leafhopper, Ernpoasca fabae (Harris), and hopperburn. A tube cage no-choice bioassay was developed to test leafhopper mortality, feeding, settling preferences, severity of hopperburn symptoms (in this case, defined as both yellowing and stem growth reduction), and trichome density and type on feeding sites. Leafhopper mortality was both strongly and significantly associated with feeding and leaf trichome density; decreased hopperburn symptom severity was weakly, although significantly, associated with increased mortality. To quantify hopperburn in terms of both yellowing and stem growth reduction, we developed a ranking system that reduces overall hopperburn expression to a single number that considers the varying responses to both types of symptoms. Great variability in leafhopper settling, leafhopper mortality, and stem glandular trichome density was detected among alfalfa genotypes, suggesting that genotypic differences may be based on the concentration and/or chemical constituency of the trichome exudates. We postulate that, among variably resistant genotypes of glandular-haired alfalfa, differences among leafhopper responses and hopperburn severity are linked to forced movement from the stems to the leaves as refuge feeding sites. Principal component analysis was performed to reduce the 10 variables down to five biologically significant factors. Scores for these factors were then used to develop resistance indices for potato leafhopper resistance, hopperburn resistance, and an overall glandular-haired alfalfa resistance index. PMID:12020025
Shockley, Floyd W; Backus, Elaine A; Ellersieck, Mark R; Johnson, David W; McCaslin, Mark
By using a forward genetic approach, a formin homology 1 gene (OsFH1) was identified as a critical regulator of rice root hair development. The phenotypic effect of OsFH1 on root hair development was verified by using three independent mutants, one point mutation and two T-DNA insertions. The study showed that OsFH1 is required for the elongation of root-hairs. However, Osfh1 exhibited growth defect of root hairs only when roots were grown submerged in solution. To understand how OsFH1 impinges on plant responses to root submergence, the growth responses of Osfh1 root hairs to anoxia, carbohydrate supplementation and exogenous hormones (auxin and ethylene) and nutrients (Fe and Pi) were examined. However, none of these treatments rescued the growth defects of Osfhl1 root hairs. This study demonstrates that OsFH1 could be involved in preventing submergence-induced inhibition of root hair growth. PMID:23733059
Huang, Jin; Liu, Jingmiao; Han, Chang-Deok
Our laboratory discovered nestin-expressing hair follicle stem cells and demonstrated their pluripotency. We have shown that\\u000a nestin-positive and K15-negative multipotent hair follicle stem cells are located above the hair follicle bulge, and we termed\\u000a these cells hair follicle pluripotent stem (hfPS) cells. We have previously shown that hair follicle stem cells can regenerate\\u000a peripheral nerve and spinal cord. In the
Yasuyuki Amoh; Lingna Li; Kensei Katsuoka; Robert M. Hoffman
It is well known that the process of plant cell differentiation depends on the symplasmic isolation of cells. Before starting the differentiation programme, the individual cell or group of cells should restrict symplasmic communication with neighbouring cells. We tested the symplasmic communication between epidermal cells in the different root zones of parental barley plants Hordeum vulgare L., cv. 'Karat' with normal root hair development, and two root hairless mutants (rhl1.a and rhl1.b). The results clearly show that symplasmic communication was limited during root hair differentiation in the parental variety, whereas in both root hairless mutants epidermal cells were still symplasmically connected in the corresponding root zone. This paper is the first report on the role of symplasmic isolation in barley root cell differentiation, and additionally shows that a disturbance in the restriction of symplasmic communication is present in root hairless mutants. PMID:23927737
Marzec, M; Muszynska, A; Melzer, M; Sas-Nowosielska, H; Kurczynska, E U
Few studies have examined the effects of chronic perchlorate exposure during growth and development, and fewer still have analyzed the effects of perchlorate over multiple generations. We describe morphological and developmental characteristics for threespine stickleback (Gasterosteus aculeatus) that were spawned and raised to sexual maturity in perchlorate-treated water (G1,2003) and for their offspring (G2,2004) that were not directly treated with perchlorate. The G1,2003 displayed a variety of abnormalities, including impaired formation of calcified traits, slower growth rates, aberrant sexual development, poor survivorship, and reduced pigmentation that allowed internal organs to be visible. Yet these conditions were absent when the offspring of contaminated fish (G2,2004) were raised in untreated water, suggesting a lack of transgenerational effects and that surviving populations may be able to recover following remediation of perchlorate-contaminated sites
Bernhardt, Richard R.; Von Hippel, Frank A.; O'Hara, Todd M.
The development of pressure ulcers in acute care settings remains an important concern, especially in high-risk populations such as patients who are critically ill and admitted to an ICU setting. In addition to immobility and other risk factors associated with critical illness, occipital pressure ulcer development has been associated with young age (neonates, infants, and young children) and patient care devices (cervical collars, bed lateral rotation). A 7-year-old boy was admitted to the pediatric intensive care unit with severe sepsis that progressed to multi-organ failure including respiratory distress requiring mechanical ventilation, cardiovascular failure requiring extracorporeal membrane oxygenation, and renal failure requiring dialysis. At 4 weeks, hair braids that were placed before admission were taken down, revealing five full-thickness occipital lesions. All wounds eventually healed, but scarring alopecia at the site of the largest wound was visible. This is the first case study describing hair braids as a potential risk factor for occipital pressure-related skin dam- age and suggests that if a patient is immobile and admitted with braids, patient/family and nursing staff education should include discussing the importance of releasing the hair to decrease the risk of occipital ulcers. PMID:21918247
Dixon, Marilu; Ratliff, Catherine
Chlorogenic acid (CGA), a product of the phenylpropanoid pathway, is one of the most widespread soluble phenolic compounds in the plant kingdom. Although CGA is known to have important roles in plant function, its relevance in plant de novo organogenesis is not yet understood. With a series of experiments, here we show that CGA has a potential role in shoot, root and root hair development. In the first phase of our investigation, we developed an efficient and novel thin cell layer (TCL) regeneration protocol for Hypericum perforatum which could bridge all the in vitro morphogenetic stages between single cell and complete plant. Tissues at different morphogenetic states were analysed for their phenolic profile which revealed that shoot differentiation from callus tissues of H. perforatum is accompanied by the onset of CGA production. Further, the relevance of CGA in de novo organogenesis was deciphered by culturing highly organogenic root explants on media augmented with various concentrations of CGA. Results of this experiment showed that CGA concentrations lower than 10.0 mg l?¹ did not affect shoot organogenesis, whereas, higher concentrations significantly reduced this process in a concentration-dependent manner. In spite of the differential concentration-dependent effects of CGA on shoot regeneration, supplementation of CGA did not have any effect on the production of lateral roots and root hairs. Interestingly, CGA showed a concentration-dependent positive correlation with lateral roots and root hairs production in the presence of ?-naphthaleneacetic acid (NAA). When the culture medium was augmented with 2-aminoindane-2-phosphonic acid (AIP), an inhibitor of phenylalanine ammonia lyase (PAL), induction of shoots, lateral roots and root hairs from the explants was significantly affected. Addition of an optimum concentration of CGA in these cultures partially restored all these organogenic processes. PMID:21700469
Franklin, G; Dias, A C P
The present study aimed to improve the gas chromatography-mass spectrometry (GC-MS) method, already developed in our laboratory, for trace analysis of diazinon in hair. Furthermore, it aimed to compare the disposition of the pesticide in the hair of two different animal species, one susceptible to diazinon toxicity and one resistant, under identical experimental conditions. Sprague Dawley rats were systemically exposed to two dose levels (6 mg/kg/day and 3 mg/kg/day) of the pesticide, through their drinking water, for a period of one and a half months. Hair samples from the back of the rats were removed before commencing the experiment and at the end of the dosing period. Diazinon was selectively isolated from pulverized hair, sample or spiked, by stepwise consequent extractions with methanol and ethyl acetate and quantified by GC-negative chemical ionization-MS. It was found that the concentration of diazinon in the hair of exposed animals was dose dependent and was found to be 0.24 +/- 0.01 ng/mg (n = 5) and 0.53 +/- 0.05 ng/mg (n = 5) for the low and high dosage, respectively. The concentration in both dose groups was much higher than the corresponding rabbit hair (rabbits were exposed to the pesticide under similar experimental conditions) as previously reported. Our results strongly point to the possibility of using hair analysis for low-level exposure monitoring of diazinon. PMID:16356339
Tutudaki, Maria; Tsatsakis, Aristidis M
Proper regulation of keratinocyte differentiation within the epidermis and follicular epithelium is essential for maintenance of epidermal barrier function and hair growth. The signaling intermediates that regulate the morphological and genetic changes associated with epidermal and follicular differentiation remain poorly understood. We tested the hypothesis that reactive oxygen species (ROS) generated by mitochondria are an important regulator of epidermal differentiation by generating mice with a keratinocyte-specific deficiency in mitochondrial transcription factor A (TFAM), which is required for the transcription of mitochondrial genes encoding electron transport chain subunits. Ablation of TFAM in keratinocytes impaired epidermal differentiation and hair follicle growth and resulted in death 2 weeks after birth. TFAM-deficient keratinocytes failed to generate mitochondria-derived ROS, a deficiency that prevented the transmission of Notch and ?-catenin signals essential for epidermal differentiation and hair follicle development, respectively. In vitro keratinocyte differentiation was inhibited in the presence of antioxidants, and the decreased differentiation marker abundance in TFAM-deficient keratinocytes was partly rescued by application of exogenous hydrogen peroxide. These findings indicate that mitochondria-generated ROS are critical mediators of cellular differentiation and tissue morphogenesis.
Hamanaka, Robert B.; Glasauer, Andrea; Hoover, Paul; Yang, Shuangni; Blatt, Hanz; Mullen, Andrew R.; Getsios, Spiro; Gottardi, Cara J.; DeBerardinis, Ralph J.; Lavker, Robert M.; Chandel, Navdeep S.
Although perturbed lipid metabolism can often lead to skin abnormality, the role of phospholipase A(2) (PLA(2)) in skin homeostasis is poorly understood. In the present study we found that group X-secreted PLA(2) (sPLA(2)-X) was expressed in the outermost epithelium of hair follicles in synchrony with the anagen phase of hair cycling. Transgenic mice overexpressing sPLA(2)-X (PLA2G10-Tg) displayed alopecia, which was accompanied by hair follicle distortion with reduced expression of genes related to hair development, during a postnatal hair cycle. Additionally, the epidermis and sebaceous glands of PLA2G10-Tg skin were hyperplasic. Proteolytic activation of sPLA(2)-X in PLA2G10-Tg skin was accompanied by preferential hydrolysis of phosphatidylethanolamine species with polyunsaturated fatty acids as well as elevated production of some if not all eicosanoids. Importantly, the skin of Pla2g10-deficient mice had abnormal hair follicles with noticeable reduction in a subset of hair genes, a hypoplasic outer root sheath, a reduced number of melanin granules, and unexpected up-regulation of prostanoid synthesis. Collectively, our study highlights the spatiotemporal expression of sPLA(2)-X in hair follicles, the presence of skin-specific machinery leading to sPLA(2)-X activation, a functional link of sPLA(2)-X with hair follicle homeostasis, and compartmentalization of the prostanoid pathway in hair follicles and epidermis. PMID:21266583
Yamamoto, Kei; Taketomi, Yoshitaka; Isogai, Yuki; Miki, Yoshimi; Sato, Hiroyasu; Masuda, Seiko; Nishito, Yasumasa; Morioka, Kiyokazu; Ishimoto, Yoshikazu; Suzuki, Noriko; Yokota, Yasunori; Hanasaki, Kohji; Ishikawa, Yukio; Ishii, Toshiharu; Kobayashi, Tetsuyuki; Fukami, Kiyoko; Ikeda, Kazutaka; Nakanishi, Hiroki; Taguchi, Ryo; Murakami, Makoto
Congenital ataxia and mental retardation are mainly caused by variations in the genes that affect brain development. Recent reports have shown that mutations in the CA8 gene are associated with mental retardation and ataxia in humans and ataxia in mice. The gene product, carbonic anhydrase-related protein VIII (CARP VIII), is predominantly present in cerebellar Purkinje cells, where it interacts with the inositol 1,4,5-trisphosphate receptor type 1, a calcium channel. In this study, we investigated the effects of the loss of function of CARP VIII during embryonic development in zebrafish using antisense morpholino oligonucleotides against the CA8 gene. Knockdown of CA8 in zebrafish larvae resulted in a curved body axis, pericardial edema and abnormal movement patterns. Histologic examination revealed gross morphologic defects in the cerebellar region and in the muscle. Electron microscopy studies showed increased neuronal cell death in developing larvae injected with CA8 antisense morpholinos. These data suggest a pivotal role for CARP VIII during embryonic development. Furthermore, suppression of CA8 expression leads to defects in motor and coordination functions, mimicking the ataxic human phenotype. This work reveals an evolutionarily conserved function of CARP VIII in brain development and introduces a novel zebrafish model in which to investigate the mechanisms of CARP VIII-related ataxia and mental retardation in humans. PMID:23087022
Aspatwar, Ashok; Tolvanen, Martti E E; Jokitalo, Eija; Parikka, Mataleena; Ortutay, Csaba; Harjula, Sanna-Kaisa E; Rämet, Mika; Vihinen, Mauno; Parkkila, Seppo
The aim of this study was to investigate the effects of actin depolymerizing factor (ADF)/destrin and position changes of kinetosomes in the development of hair cells following Atoh1-induced ectopic regeneration in the basilar membrane of mice. We observed through immunofluorescence at various time-points the expression of ADF/destrin and the specific kinetosome marker, ?-tubulin, in hair cells following ectopic regeneration induced by adenovirus transfection, overexpression of Atoh1 and in vitro culture. Changes of ADF/destrin distribution and kinetosome position during in vitro culture of new hair cells [Myo7a(+)] following Atoh1-induced ectopic regeneration are consistent with the changes in ADF/destrin expression and the polar migration of kinetosomes in hair cells of the cochlear sensory epithelium in normal development. ADF/destrin is involved in the development of the auditory epithelium and the development and structural rearrangement of ectopically regenerated hair cells in mammals. The kinetosomes of hair cells following Atoh1-induced ectopic regeneration show positional changes in vitro at different time-points.
JIN, KAI; REN, DONG-DONG; CHI, FANG-LU; YANG, JUAN-MEI; HUANG, YI-BO; LI, WEN
Summary The cytoarchitecture and the pattern of cytoplasmic streaming change during the development of root hairs ofMedicago truncatula and after a challenge with nodulation (Nod) factors. We measured the speed and orientation of movement of 1–2 ?m long organelles.\\u000a The speed of organelle movement in cytoplasmic strands in the basal part of growing root hairs is 8–14 ?m\\/s and is of
Björn Sieberer; Anne Mie C. Emons
Male embryonic mice with mutations in the X-linked aristaless-related homeobox gene (Arx) developed with small brains due to suppressed proliferation and regional deficiencies in the forebrain. These mice also showed aberrant migration and differentiation of interneurons containing ?-aminobutyric acid (GABAergic interneurons) in the ganglionic eminence and neocortex as well as abnormal testicular differentiation. These characteristics recapitulate some of the clinical
Kunio Kitamura; Masako Yanazawa; Noriyuki Sugiyama; Hirohito Miura; Akiko Iizuka-Kogo; Masatomo Kusak; Kayo Omichi; Rika Suzuki; Yuko Kato-Fukui; Kyoko Kamiirisa; Mina Matsuo; Shin-ichi Kamijo; Megumi Kasahara; Hidefumi Yoshioka; Tsutomu Ogata; Takayuki Fukuda; Ikuko Kondo; Mitsuhiro Kato; William B. Dobyns; Minesuke Yokoyama; Ken-ichirou Morohashi
Background: Correct staging of puberty is essential in order to differentiate different pathologies, as various components of the endocrine system influence breast, pubic, and axillary hair development. Aims: To determine the current timing of adrenarche and breast development in Lithuanian preadolescent schoolgirls. Methods: Cross-sectional study of 1231 schoolgirls aged 7.0–11.6 years. Puberty was staged according to the method of Tanner. Mean age at entry into each pubertal stage was calculated by probit analysis. Results: Of the 255 girls aged 7 years, two had premature adrenarche (0.8%) and one premature thelarche (0.4%). Mean age of onset of pubic/axillary hair development was 11.0 years, and for breast development (Stage 2) 10.2 years. Breast Stage 3 development was attained at 11.3 years and Stage 4 at 13.9 years. Mean BMI, height, weight, and systolic blood pressure SD scores were higher in pubertal than in prepubertal girls. Skinfold thickness was also significantly higher in girls with isolated adrenarche than in prepubertal girls. The increase in BMI and weight resulted from an increase in body fat as evidenced by measures of subscapular and triceps skinfold thickness. Girls with only signs of adrenarche or thelarche did not differ from each other from the anthropometric standpoint. Conclusions: Premature thelarche and premature adrenarche were relatively uncommon in this population. Pubertal onset was slightly earlier than the UK Tanner standards and tended to occur in girls with a higher BMI.
Zukauskaite, S; Lasiene, D; Lasas, L; Urbonaite, B; Hindmarsh, P
Cdc42 is a key regulator of dynamic actin organization. However, little is known about how Cdc42-dependent actin regulation influences steady-state actin structures in differentiated epithelia. We employed inner ear hair-cell-specific conditional knockout to analyze the role of Cdc42 in hair cells possessing highly elaborate stable actin protrusions (stereocilia). Hair cells of Atoh1-Cre;Cdc42(flox/flox) mice developed normally but progressively degenerated after maturation, resulting in progressive hearing loss particularly at high frequencies. Cochlear hair cell degeneration was more robust in inner hair cells than in outer hair cells, and began as stereocilia fusion and depletion, accompanied by a thinning and waving circumferential actin belt at apical junctional complexes (AJCs). Adenovirus-encoded GFP-Cdc42 expression in hair cells and fluorescence resonance energy transfer (FRET) imaging of hair cells from transgenic mice expressing a Cdc42-FRET biosensor indicated Cdc42 presence and activation at stereociliary membranes and AJCs in cochlear hair cells. Cdc42-knockdown in MDCK cells produced phenotypes similar to those of Cdc42-deleted hair cells, including abnormal microvilli and disrupted AJCs, and downregulated actin turnover represented by enhanced levels of phosphorylated cofilin. Thus, Cdc42 influenced the maintenance of stable actin structures through elaborate tuning of actin turnover, and maintained function and viability of cochlear hair cells. PMID:24610943
Ueyama, Takehiko; Sakaguchi, Hirofumi; Nakamura, Takashi; Goto, Akihiro; Morioka, Shigefumi; Shimizu, Aya; Nakao, Kazuki; Hishikawa, Yoshitaka; Ninoyu, Yuzuru; Kassai, Hidetoshi; Suetsugu, Shiro; Koji, Takehiko; Fritzsch, Bernd; Yonemura, Shigenobu; Hisa, Yasuo; Matsuda, Michiyuki; Aiba, Atsu; Saito, Naoaki
The management of disorders of sexual development (DSD) in humans and domestic animals has been the subject of intense interest for decades. The association between abnormal chromosome constitutions and DSDs in domestic animals has been recorded since the beginnings of conventional cytogenetic analysis. Deviated karyotypes consisting of abnormal sex chromosome sets and\\/or the coexistence of cells with different sex chromosome
L. A. Favetta; D. A. F. Villagómez; L. Iannuzzi; G. Di Meo; A. Webb; S. Crain; W. A. King
BACKGROUND: A correlation between morphology, developmental competence and chromosome abnormalities is established. However, since absolute correlations are rare, embryo selection remains one of the most arduous tasks in assisted reproduction. This study was undertaken in order to determine which chromosomal abnormalities are compatible with development to the blastocyst stage. METHODS: Embryos diagnosed by preimplantation genetic diagnosis (PGD) as chromosomally abnormal
M. Sandalinas; S. Sadowy; M. Alikani; G. Calderon; J. Cohen
Tunicates are unique animals for studying the origin and evolution of vertebrates because they are considered vertebrates' closest living relatives and share the vertebrate body plan and many specific features. Both possess neural placodes, transient thickenings of the cranial ectoderm that give rise to various types of sensory cells, including axonless secondary mechanoreceptors. In vertebrates, these are represented by the hair cells of the inner ear and the lateral line, which have an apical apparatus typically bearing cilia and stereovilli. In tunicates, they are found in the coronal organ, which is a mechanoreceptor located at the base of the oral siphon along the border of the velum and tentacles and is formed of cells bearing a row of cilia and short microvilli. The coronal organ represents the best candidate homolog for the vertebrate lateral line. To further understand the evolution of secondary sensory cells, we analysed the development and cytodifferentiation of coronal cells in the tunicate ascidian Ciona intestinalis for the first time. Here, coronal sensory cells can be identified as early as larval metamorphosis, before tentacles form, as cells with short cilia and microvilli. Sensory cells gradually differentiate, acquiring hair cell features with microvilli containing actin and myosin VIIa; in the meantime, the associated supporting cells develop. The coronal organ grows throughout the animal's lifespan, accompanying the growth of the tentacle crown. Anti-phospho Histone H3 immunostaining indicates that both hair cells and supporting cells can proliferate. This finding contributes to the understanding of the evolution of secondary sensory cells, suggesting that both ancestral cell types were able to proliferate and that this property was progressively restricted to supporting cells in vertebrates and definitively lost in mammals. PMID:23876523
Gasparini, Fabio; Caicci, Federico; Rigon, Francesca; Zaniolo, Giovanna; Burighel, Paolo; Manni, Lucia
Hairless mice carrying homozygous mutations in hairless gene manifest rudimentary hair follicles (HFs), epidermal cysts, hairless phenotype, and enhanced susceptibility to squamous cell carcinomas. However, their susceptibility to basal cell carcinomas (BCCs), a neoplasm considered originated from HF-localized stem cells, is unknown. To demonstrate the role of HFs in BCC development, we bred Ptch(+/-)/C57BL6 with SKH-1 hairless mice, followed by brother-sister cross to get F2 homozygous mutant (hairless) or wild-type (haired) mice. UVB-induced inflammation was less pronounced in shaved haired than in hairless mice. In hairless mice, inflammatory infiltrate was found around the rudimentary HFs and epidermal cysts. Expression of epidermal IL1f6, S100a8, vitamin D receptor, repetin, and major histocompatibility complex II, biomarkers depicting susceptibility to cutaneous inflammation, was also higher. In these animals, HF disruption altered susceptibility to UVB-induced BCCs. Tumor onset in hairless mice was 10 weeks earlier than in haired littermates. The incidence of BCCs was significantly higher in hairless than in haired animals; however, the magnitude of sonic hedgehog signaling did not differ significantly. Overall, 100% of hairless mice developed >12 tumors per mouse after 32 weeks of UVB therapy, whereas haired mice developed fewer than three tumors per mouse after 44 weeks of long-term UVB irradiation. Tumors in hairless mice were more aggressive than in haired littermates and manifested decreased E-cadherin and enhanced mesenchymal proteins. These data provide novel evidence that disruption of HFs in Ptch(+/-) mice enhances cutaneous susceptibility to inflammation and BCCs. PMID:24631180
Xu, Jianmin; Weng, Zhiping; Arumugam, Aadithya; Tang, Xiuwei; Chaudhary, Sandeep C; Li, Changzhao; Christiano, Angela M; Elmets, Craig A; Bickers, David R; Athar, Mohammad
Vascular endothelial growth factors (VEGFs) play important roles in neovascularization, tissue development, and angiogenesis. In this study, changes in VEGF expression patterns and microvessel density (MVD), and their correlations, were investigated during hair follicle development in epidermal appendages of Liaoning cashmere goats. Polyclonal antibodies to VEGF and microvessels were used for monthly immunohistochemical examinations of normal skin specimens from adult female goats for one year. VEGF was expressed in the hair bulb of primary and secondary hair follicles, the outer and inner root sheaths, sebaceous glands (ductal and secretory portions), eccrine sweat glands (ductal and secretory portions), and the epidermis. Abundant expression of VEGF was observed in the follicular basement membrane zone surrounding the bulb matrix and in ductal and secretory portions of eccrine sweat glands. The change in VEGFs in primary hair follicles showed a bimodal pattern, with the first peak observed from March to May, and the second in August. Maximal expression in secondary hair follicles occurred in May and August. Therefore, VEGF expression in primary and secondary hair follicles is synchronized throughout the year, and is correlated to hair development. In the later telogen and anagen phases, VEGF expression was higher in the secondary, compared to the primary, hair follicle. Changes in MVD also showed a bimodal pattern with peaks in May and August. VEGF expression and MVD showed moderate and strongly positive correlation in the primary and secondary hair follicles, respectively. Therefore, MVD and VEGF are closely related to the processes involved in hair cycle regulation. PMID:24390991
Zhang, Q L; Li, J P; Li, Y M; Chang, Q; Chen, Y; Jiang, H Z; Zhao, Z H; Guo, D
Manganese (Mn) is the second most prevalent transition metal in the Earth's crust but its availability is often limited due to rapid oxidation and low mobility of the oxidized forms. Acclimation to low Mn availability was studied in Arabidopsis seedlings subjected to Mn deficiency. As reported here, Mn deficiency caused a thorough change in the arrangement and characteristics of the root epidermal cells. A proportion of the extra hairs formed upon Mn deficiency were located in atrichoblast positions, indicative of a post-embryonic reprogramming of the cell fate acquired during embryogenesis. When plants were grown under a light intensity of >50 micromol m(-2) s(-1) in the presence of manganese root hair elongation was substantially inhibited, whereas Mn-deficient seedlings displayed stimulated root hair development. GeneChip analysis revealed several candidate genes with potential roles in the reprogramming of rhizodermal cells. None of the genes that function in epidermal cell fate specification were affected by Mn deficiency, indicating that the patterning mechanism which controls the differentiation of rhizodermal cells during embryogenesis have been bypassed under Mn-deficient conditions. This assumption is supported by the partial rescue of the hairless cpc mutant by Mn deficiency. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) analysis revealed that, besides the anticipated reduction in Mn concentration, Mn deficiency caused an increase in iron concentration. This increase was associated with a decreased transcript level of the iron transporter IRT1, indicative of a more efficient transport of iron in the absence of Mn. PMID:18772308
Yang, Thomas Ju Wei; Perry, Paula Jay; Ciani, Silvano; Pandian, Sundaravel; Schmidt, Wolfgang
Argues that knowledge from studies of individuals with sex chromosome abnormalities can further understanding of aspects of normal human development. Studies of XO girls, XXY boys, XXX girls, and males with a fragile X chromosome are summarized to demonstrate how results contribute to knowledge about normal cognitive development and about…
The effects of prenatal low-dose irradiation with heavy ions on embryonic development in mice and on melanocyte differentiation are not well understood. We performed whole-body irradiation of pregnant C57BL/10J mice at embryonic Day 9 (E9) with a single dose of ?-rays, silicon, argon or iron ions. The number of living embryos and embryonic body weight at E18 decreased after exposure to heavy ions at high doses. Malformations such as small eyes and limb anomalies were observed in heavy-ion-treated embryos, but not in ?-ray-treated embryos. The frequency of abnormally curved tails was increased by exposure to ?-rays and argon and iron ions even at a dose of 0.1 Gy (P < 0.05). In contrast, a dose-dependent decrease in the number of epidermal melanoblasts/melanocytes and hair bulb melanocytes was observed after 0.1 Gy irradiation with ?-rays or heavy ions (P < 0.01). The decrease in the number of dorsal hair bulb melanocytes, dorsal and ventral epidermal melanoblasts/melanocytes and ventral hair bulb melanocytes was not necessarily correlated with the linear energy transfer of the radiation tested. Moreover, the effects of heavy ions were larger on the ventral skin than on the dorsal skin, indicating that the sensitivity of melanocytes to heavy ions differs between the dorsal and ventral skin. Taken together, these results suggest that the effects of the low-dose heavy ions differ between cell types and tissues, and the effects on the prenatal development of mice and melanocyte development are not necessarily greater than those of ?-rays.
Hirobe, Tomohisa; Eguchi-Kasai, Kiyomi; Sugaya, Kimihiko; Murakami, Masahiro
Reaction-diffusion models have been used as a paradigm for describing the de novo emergence of biological patterns such as stripes and spots. In many organisms, these initial patterns are typically refined and elaborated over the subsequent course of development. Here we study the formation of secondary hair follicle patterns in the skin of developing mouse embryos. We used the expression of sex-determining region Y box 2 to identify and distinguish the primary and secondary hair follicles and to infer the spatiotemporal dynamics of the follicle formation process. Quantitative analysis of the specific follicle patterns observed reveals a simple geometrical rule governing the formation of secondary follicles, and motivates an expansion-induction (EI) model in which new follicle formation is driven by the physical growth of the embryo. The EI model requires only one diffusible morphogen and provides quantitative, accurate predictions on the relative positions and timing of secondary follicle formation, using only the observed configuration of primary follicles as input. The same model accurately describes the positions of additional follicles that emerge from skin explants treated with an activator. Thus, the EI model provides a simple and robust mechanism for predicting secondary space-filling patterns in growing embryos. PMID:24550288
Cheng, Chi Wa; Niu, Ben; Warren, Mya; Pevny, Larysa Halyna; Lovell-Badge, Robin; Hwa, Terence; Cheah, Kathryn S E
Hair cells detect and process sound and movement information, and transmit this with remarkable precision and efficiency to afferent neurons via specialized ribbon synapses. The zebrafish is emerging as a powerful model for genetic analysis of hair cell development and function both in vitro and in vivo. However, the full exploitation of the zebrafish is currently limited by the difficulty in obtaining systematic electrophysiological recordings from hair cells under physiological recording conditions. Thus, the biophysical properties of developing and adult zebrafish hair cells are largely unknown. We investigated potassium and calcium currents, voltage responses and synaptic activity in hair cells from the lateral line and inner ear in vivo and using near-physiological in vitro recordings. We found that the basolateral current profile of hair cells from the lateral line becomes more segregated with age, and that cells positioned in the centre of the neuromast show more mature characteristics and those towards the edge retain a more immature phenotype. The proportion of mature-like hair cells within a given neuromast increased with zebrafish development. Hair cells from the inner ear showed a developmental change in current profile between the juvenile and adult stages. In lateral line hair cells from juvenile zebrafish, exocytosis also became more efficient and required less calcium for vesicle fusion. In hair cells from mature zebrafish, the biophysical characteristics of ion channels and exocytosis resembled those of hair cells from other lower vertebrates and, to some extent, those in the immature mammalian vestibular and auditory systems. We show that although the zebrafish provides a suitable animal model for studies on hair cell physiology, it is advisable to consider that the age at which the majority of hair cells acquire a mature-type configuration is reached only in the juvenile lateral line and in the inner ear from >2 months after hatching.
Olt, Jennifer; Johnson, Stuart L; Marcotti, Walter
Chronic centrifugation of 85- to 92-day-old Beagles at 2.0 x g and 2.6 x g for 26 weeks during the time of active skeletal growth caused skeletal abnormalities in the radius and the ulna of ten of 11 dogs. The pattern of change mimicked that found in naturally occurring and experimentally induced premature distal ulnar physeal closure or delayed growth at this physis. Minimal changes in bone density were detected by sensitive photon absorptiometric techniques. Skeletal abnormalities also were found in five of the six cage-control dogs, although the run-control dogs were radiographically normal.
Morgan, J. P.; Fisher, G. L.; McNeill, K. L.; Oyama, J.
The Ames waltzer (av) mouse mutant exhibits auditory and vestibular abnormalities resulting from mutation of protocadherin 15 (Pcdh15). Ames waltzer has been identified as an animal model for inner ear pathology associated with Usher syndrome type 1F. Studies correlating anatomical phenotype with severity of genetic defect in various av alleles are providing better understanding of the role played by Pcdh15 in inner ear development and of sensorineural abnormalities associated with alterations in Pcdh15 protein structure as a result of gene mutation. In this work we present new findings on inner ear pathology in four alleles of av mice with differing mutations of Pcdh15 as well as varying alterations in inner ear morphology. Two alleles with in-frame deletion mutations (Pcdh15 (av-J) and Pcdh15 (av-2J)) and two presumptive functional null alleles (Pcdh15 (av-3J) and Pcdh15 (av-Tg)) were studied. Light and electron microscopic observations demonstrated that the severity of cochlear and vestibular pathology in these animals correlates positively with the extent of mutation in Pcdh15 from embryonic day 18 (E18) up to 12 months. Electron microscopic analysis of immature ears indicated early abnormalities in the arrangement of stereocilia and the inner and outer hair cell cuticular plates, stereocilia rootlets, and the actin meshwork within the cuticular plate. In severe cases, displacement of the kinocilium and alterations in the shape of the cuticular plate was also observed. Mice harboring in-frame deletion mutations showed less disorganization of stereocilia and cuticular plates in the organ of Corti than the presumptive functional null alleles at P0-P10. A slower progression of pathology was also seen via light microscopy in older animals with in-frame deletions, compared to the presumptive functional null mutations. In summary, our results demonstrate that mutation in Pcdh15 affects the initial formation of stereocilia bundles with associated changes in the actin meshwork within the cuticular plate; these effects are more pronounced in the presumed null mutation compared to mutations that only affect the extracellular domain. The positive correlation of severity of effects with extent of mutation can be seen well into adulthood. PMID:16408167
Pawlowski, Karen S; Kikkawa, Yayoi S; Wright, Charles G; Alagramam, Kumar N
Cartilage hair hypoplasia (CHH), is a rare cause of metaphyseal chondrodysplasia and short stature. Other featuresincluded hair abnormality, immunodeficiency, anemia, gastrointestinal disorders (Hirschsprung disease,celiac, …) and increased risk of cancer. The disease is an autosomal recessive disorder and previously has notbeen reported in Iran. We report a 9-year-old boy diagnosed as cartilage hair hypoplasia, with severe short stature,metaphyseal chondrodysplasia, hair hypoplasia, Hirschsprung disease, hypothyroidism, vesicouretral refluxand renal stone. Renal stone and hypothyroidism have been reported in cartilage hair hypoplasia with lower frequencies.This is the first report of cartilage hair hypoplasia in Iran. PMID:24791127
Shiasi Arani, Kobra
Active polar transport establishes directional auxin flow and the generation of local auxin gradients implicated in plant responses and development. Auxin modulates gravitropism at the root tip and root hair morphogenesis at the differentiation zone. Genetic and biochemical analyses provide evidence for defective basipetal auxin transport in trh1 roots. The trh1, pin2, axr2 and aux1 mutants, and transgenic plants overexpressing PIN1, all showing impaired gravity response and root hair development, revealed ectopic PIN1 localization. The auxin antagonist hypaphorine blocked root hair elongation and caused moderate agravitropic root growth, also leading to PIN1 mislocalization. These results suggest that auxin imbalance leads to proximal and distal developmental defects in Arabidopsis root apex, associated with agravitropic root growth and root hair phenotype, respectively, providing evidence that these two auxin-regulated processes are coupled. Cell-specific subcellular localization of TRH1-YFP in stele and epidermis supports TRH1 engagement in auxin transport, and hence impaired function in trh1 causes dual defects of auxin imbalance. The interplay between intrinsic cues determining root epidermal cell fate through the TTG/GL2 pathway and environmental cues including abiotic stresses modulates root hair morphogenesis. As a consequence of auxin imbalance in Arabidopsis root apex, ectopic PIN1 mislocalization could be a risk aversion mechanism to trigger root developmental responses ensuring root growth plasticity. PMID:23252740
Rigas, Stamatis; Ditengou, Franck Anicet; Ljung, Karin; Daras, Gerasimos; Tietz, Olaf; Palme, Klaus; Hatzopoulos, Polydefkis
Here, we studied hair follicle development of Liaoning Cashmere goats. Every month for 1 year, skin samples were collected from five 1.5-year-old female goats, and made into paraffin sections. A number of parameters were measured of primary and secondary hair follicles via microscopic observation including follicle depth, hair bulb width, dermis and epidermis thickness, changes in follicle activity, and histology. The results showed the presence of three phases in the annual hair cycle: anagen, catagen, and telogen. Primary and secondary hair follicle depth varied across the months; however, no significant difference was obtained between adjacent months (P > 0.05). Primary hair follicles had a bigger hair bulb width compared to secondary hair follicles; however, this difference declined during hair follicle developed in anagen. As hair follicle growth slowed, the hair bulb broadened, and hair root depth became shallower. During the entire hair cycle, hair follicle depth and dermis thickness were positively correlated; however, this relationship was not significant (P > 0.05) for primary and secondary hair follicle density and the ratio of secondary hair follicle density and primary hair follicle density (S/P ratio). In addition, new and old primary hair follicles coexisted with secondary hair follicles. Finally, secondary hair follicles had a higher activity rate compared to primary hair follicle in adult Liaoning Cashmere goats in certain months. PMID:25036348
Zhang, Q L; Li, J P; Chen, Y; Chang, Q; Li, Y M; Yao, J Y; Jiang, H Z; Zhao, Z H; Guo, D
Hair follicles represent reservoirs for localized drug therapy and transport pathways for systemic drug delivery. This study describes an approach towards developing a novel procedure for quantifying topically applied substances located in the hair follicles of porcine ear skin, a model for human in vivo skin, using a fluorescent dye. Approximately 5% of the topically applied dye was recovered from the hair follicles, which is in accordance with a previous study. PMID:23489479
Knorr, Fanny; Patzelt, Alexa; Richter, Heike; Schanzer, Sabine; Sterry, Wolfram; Lademann, Juergen
The accurate perception of sound frequency by vertebrates relies upon the tuning of hair cells, which are arranged along auditory organs according to frequency. This arrangement, which is termed a tonotopic gradient, results from the coordination of many cellular and extracellular features. Seeking the mechanisms that orchestrate those features and govern the tonotopic gradient, we used expression microarrays to identify genes differentially expressed between the high- and low-frequency cochlear regions of the chick (Gallus gallus). Of the three signaling systems that were represented extensively in the results, we focused on the notch pathway and particularly on DNER, a putative notch ligand, and PTP?, a receptor phosphatase that controls DNER trafficking. Immunohistochemistry confirmed that both proteins are expressed more strongly in hair cells at the cochlear apex than in those at the base. At the apical surface of each hair cell, the proteins display polarized, mutually exclusive localization patterns. Using morpholinos to decrease the expression of DNER or PTP? as well as a retroviral vector to overexpress DNER, we observed disturbances of hair-bundle morphology and orientation. Our results suggest a role for DNER and PTP? in hair-cell development and possibly in the specification of tonotopy.
Kowalik, Lukasz; Hudspeth, A. J.
If youÃ¯Â¿Â½ve ever had a question about the biological make-up of your hair or anyone elseÃ¯Â¿Â½s, then this website is the place to go for answers. The Hair Biology portion of the Keratin web page gives incredible detail on hair fiber, follicles, growth cycle stages, hair length and density. These are just a few of the biological aspects of hair and much more is addressed and covered in great detail on the site. Hair Biology also features photography of different stages of hair growth along with a FAQ section which may answer some commonly asked (and not so commonly) questions about hair. Overall, this site would be an invaluable tool for anyone in the industry or anyone aspiring to join.
The hair cosmetic industry has undergone a revolutionary change over the last two decades. The focus has dramatically veered from merely cleaning to repair, increasing the tensile strength, reducing oxidative damage, and stimulating growth. Newer shorter procedures to make hair look naturally more lustrous, smooth, and manageable have evolved. Specialized grooming products have been formulated to cleanse, calm, and condition the hair, and are tailored for different hair-types, for example, dry, dry-damaged, oily, colored, and gray hair. Other products are formulated to alter the color or structure of the hair shaft, for example, hair dyes, perming/relaxing. Hair sprays and waxes/gels, can alter the 'lift' of the hair-shaft. Although dermatologists are experts in managing scalp and hair diseases, the esthetic applications of newer cosmetic therapies still remain elusive. This article attempts to fill the lacunae in our knowledge of hair cosmetics and esthetic procedures relevant in today's rapidly changing beauty-enhancing industry, with special emphasis on the Indian scenario for chemical and 'natural' hair products. PMID:23974582
Madnani, Nina; Khan, Kaleem
Children with autism were examined to determine amounts of mercury (Hg) in their baby hair and the factors that might affect Hg body burden. US children with autism (n = 78) and matched controls (n = 31) born between 1988 and 1999 were studied. Hg in first-cut baby hair was determined using cold vapor atomic fluorescence spectrometry (CVAFS). Twenty samples were split and also
J. B. Adams; J. Romdalvik; K. E. Levine; L.-W. Hu
Those who dye their hair frequently manifest allergic contact dermatitis (ACD) from p-phenylenediamine (PPD)-containing hair dye. PPD is known to be the most frequent sensitizer in hair dye, but there has been no documentation of this sensitizer having a role in chronic dermatologic conditions. Our department experienced a case of a 62-year-old woman with lichen simplex chronicus (LSC), who complained of aggravation after hair dyeing and made such an association. We conducted a prospective and retrospective study to further evaluate the clinical associations between the two. In our prospective study, patch testing was performed in selected patients who regularly carried out hair dyeing and also had clinical manifestations of LSC. Also a retrospective examination was conducted in cases where patch testing had been performed with PPD in the past for suspected ACD and further selected cases with concurrent LSC and/or other neurodermatitis. 11 and 14 patients in our prospective and retrospective study, respectively, presented with both LSC and positive findings to PPD. 5 (45.5%) and 4 (28.6%) patients in our prospective and retrospective study showed clinical relevance from clinical improvement after stopping use and rechallenge. We report several cases of patients diagnosed as having LSC and/or prurigo nodularis who showed clinical improvement after discontinuing the use of hair dye. The suggestion can therefore be made that hair dye could be a possible aetiologic agent causing LSC in those using hair dyes. PMID:15291824
Chey, Won Young; Kim, Kyung Lok; Yoo, Tae-Yeon; Lee, Ai-Young
The treatment of hair loss diseases is sometimes difficult because of insufficient efficacy and limited options. However, recent advances in understanding of the pathophysiology and development of new remedies have improved the treatment of refractory hair loss conditions. In this article, an update on the management of hair loss diseases is provided, especially focusing on recently reported therapeutic approaches for
Selected immunophilin ligands (IPLs) are not only potent immunosuppressants but also modulate hair growth. Their considerable side effects, however, justify at best topical applications of these drugs for the management of clinical hair growth disorders. Therefore, we have explored hair growth manipulation by topical cyclosporin A (CsA) and FK 506 in previously established murine models that mimic premature hair follicle regression (catagen) or chemotherapy-induced alopecia, two major pathomechanisms underlying human hair loss. We confirm that topical CsA and FK 506 induce active hair growth (anagen) in the back skin of C57BL/6 mice with all follicles in the resting stage (telogen) and show that both IPLs also inhibit massive, dexamethasone-induced, premature catagen development in these mice. Furthermore, we demonstrate that CsA and FK 506 provide relative protection from alopecia and follicle dystrophy induced by cyclophosphamide, possibly by favoring the dystrophic anagen pathway of follicle response to chemical damage. Although it remains to be established whether these IPLs exert the same effects on human hair follicles, our study provides proof of the principle that topical IPLs can act as potent manipulators of clinically relevant hair-cycling pathomechanisms. This strongly encourages one to explore the use of topical IPLs in the management of human hair growth disorders. Images Figure 2 Figure 3 Figure 6 Figure 9
Maurer, M.; Handjiski, B.; Paus, R.
\\u000a \\u000a Abstract Hair can be engineered at different levels—its structure and surface—through modification of its constituent molecules, in\\u000a particular proteins, but also the hair follicle (HF) can be genetically altered, in particular with the advent of siRNA-based\\u000a applications. General aspects of hair biology are reviewed, as well as the most recent contributions to understanding hair\\u000a pigmentation and the regulation of hair development.
Rita Araújo; Margarida Fernandes; Artur Cavaco-Paulo; Andreia Gomes
Organ regenerative therapy aims to reproduce fully functional organs to replace organs that have been lost or damaged as a result of disease, injury, or aging. For the fully functional regeneration of ectodermal organs, a concept has been proposed in which a bioengineered organ is developed by reproducing the embryonic processes of organogenesis. Here, we show that a bioengineered hair follicle germ, which was reconstituted with embryonic skin-derived epithelial and mesenchymal cells and ectopically transplanted, was able to develop histologically correct hair follicles. The bioengineered hair follicles properly connected to the host skin epithelium by intracutaneous transplantation and reproduced the stem cell niche and hair cycles. The bioengineered hair follicles also autonomously connected with nerves and the arrector pili muscle at the permanent region and exhibited piloerection ability. Our findings indicate that the bioengineered hair follicles could restore physiological hair functions and could be applicable to surgical treatments for alopecia.
Asakawa, Kyosuke; Toyoshima, Koh-ei; Ishibashi, Naoko; Tobe, Hirofumi; Iwadate, Ayako; Kanayama, Tatsuya; Hasegawa, Tomoko; Nakao, Kazuhisa; Toki, Hiroshi; Noguchi, Shotaro; Ogawa, Miho; Sato, Akio; Tsuji, Takashi
The inner root sheath (IRS) allows the exit of hairs through the epidermal surface. The fine structure of monotreme and marsupial IRS and trichohyalin is not known. Using electron microscopy and immunocytochemistry, the localization of trichohyalin and transglutaminase have been studied in monotreme and marsupial hairs, and compared with trichohyalin localization in placental hairs. Trichohyalin in all mammalian species studied here is recognized by a polyclonal antibody against sheep trichohyalin. This generalized immunoreactivity suggests that common epitopes are present in trichohyalin across mammals. In differentiating IRS cells, trichohyalin granules of variable dimensions are composed of an immunolabelled amorphous matrix associated with a network of 10–12-nm-thick keratin filaments. Transglutaminase labelling is present among keratin bundles and trichohyalin granules, and in condensed nuclei of terminally differentiating cells of the inner root sheath. The IRS in monotreme hairs is multistratified but lacks a distinguishable Henle layer. Cornification of IRS determines the sculpturing of the fibre cuticle and later shedding from the follicle for the exit of the hair fibre on the epidermal surface. It is hypothesized that the stratification of IRS in Henle, Huxley and IRS cuticle layers is derived from a simpler organization, like that present in the IRS of monotremes. The IRS is regarded as a localized shedding/sloughing layer needed for the exit of hairs without injury to the epidermis. The formation of the IRS during the evolution of mammalian epidermis allowed the physiological exit of hairs produced inside the skin. The peculiar morphogenesis of hairs in possible primitive skins, such as those of the monotremes (mammals with some reptilian characteristics) or the tails of some rodents (a scaled skin), may elucidate the evolution of hairs. In monotreme and rodent tail skin, the dermal papilla remains localized on the proximal side of the hair peg and forms a hair placode with bilateral symmetry. The papilla is progressively surrounded by the down-growing hair peg until a dermal papilla with radial symmetry is formed. It is speculated that the progressive reduction of the extended dermal papilla of reptilian scales into small and deep papillae of therapsid reptiles produced hairs in mammals.
The retinoblastoma protein pRb is required for cell-cycle exit of embryonic mammalian hair cells but not for their early differentiation. However, its role in postnatal hair cells is unknown. To study the function of pRb in mature animals, we created a new conditional mouse model, with the Rb gene deleted primarily in the inner ear. Progeny survive up to 6
Cyrille Sage; Mingqian Huang; Melissa A. Vollrath; M. Christian Brown; Philip W. Hinds; David P. Corey; Douglas E. Vetter; Zheng-Yi Chen
Plasma membrane-associated Ca(2+) -binding protein-2 (PCaP2) of Arabidopsis thaliana is a novel-type protein that binds to the Ca(2+) /calmodulin complex and phosphatidylinositol phosphates (PtdInsPs) as well as free Ca(2+) . Although the PCaP2 gene is predominantly expressed in root hair cells, it remains unknown how PCaP2 functions in root hair cells via binding to ligands. From biochemical analyses using purified PCaP2 and its variants, we found that the N-terminal basic domain with 23 amino acids (N23) is necessary and sufficient for binding to PtdInsPs and the Ca(2+) /calmodulin complex, and that the residual domain of PCaP2 binds to free Ca(2+) . In mutant analysis, a pcap2 knockdown line displayed longer root hairs than the wild-type. To examine the function of each domain in root hair cells, we over-expressed PCaP2 and its variants using the root hair cell-specific EXPANSIN A7 promoter. Transgenic lines over-expressing PCaP2, PCaP2(G2A) (second glycine substituted by alanine) and ?23PCaP2 (lacking the N23 domain) exhibited abnormal branched and bulbous root hair cells, while over-expression of the N23 domain suppressed root hair emergence and elongation. The N23 domain was necessary and sufficient for the plasma membrane localization of GFP-tagged PCaP2. These results suggest that the N23 domain of PCaP2 negatively regulates root hair tip growth via processing Ca(2+) and PtdInsP signals on the plasma membrane, while the residual domain is involved in the polarization of cell expansion. PMID:23445487
Kato, Mariko; Aoyama, Takashi; Maeshima, Masayoshi
\\u000a Hirsutism is represented by excessive growth of the coarse hairs in women, distributed in a male-like pattern. Hypertrichosis\\u000a is represented by excessive growth of coarser and longer hair than is normal for the age, sex and race of the person. The\\u000a hair growth cycle has three phases: anagen, catagen and telogen. The anagen phase is the growth phase, the catagen
Lucian Fodor; Yehuda Ullmann; Monica Elman
The aim of this study was to investigate the number and type of brain abnormalities and their influence on psychosocial development, criminal history and paraphilias in sexual murderers. We analyzed psychiatric court reports of 166 sexual murderers and compared a group with notable signs of brain abnormalities (N = 50) with those without any signs (N = 116). Sexual murderers with brain abnormalities suffered more from early behavior problems. They were less likely to cohabitate with the victim at the time of the homicide and had more victims at the age of six years or younger. Psychiatric diagnoses revealed a higher total number of paraphilias: Transvestic fetishism and paraphilias not otherwise specified were more frequent in offenders with brain abnormalities. A binary logistic regression identified five predictors that accounted for 46.8% of the variance explaining the presence of brain abnormalities. Our results suggest the importance of a comprehensive neurological and psychological examination of this special offender group. PMID:16225232
Briken, Peer; Habermann, Niels; Berner, Wolfgang; Hill, Andreas
The mechanisms of root hair formation have been studied extensively in Arabidopsis but knowledge about these processes in monocot species is still limited, especially in relation to the proteome level. The aim of this study was to identify the proteins that are involved in the initiation and the early stage of root hair tip growth in barley using two-dimensional (2D) electrophoresis and mass spectrometry. A comparison of proteins that accumulate differentially in two root hair mutants and their respective parent varieties resulted in the identification of 13 proteins that take part in several processes related to the root hair morphogenesis, such as the control of vesicular trafficking, ROS signalling and homeostasis, signal transduction by phospholipids metabolism and ATP synthesis. Among the identified proteins, two ATP synthases, two ABC transporters, a small GTPase from the SAR1 family, a PDI-like protein, a monodehydroascorbate reductase, a C2 domain-containing protein and a Wali7 domain-containing protein were found. This study is the first report on the proteins identified in the initial stage of root hair formation in barley and gives new insights into the mechanisms of root hair morphogenesis in a monocot species. PMID:22847350
Janiak, Agnieszka; Piórko, Stanis?aw; Matros, Andrea; Mock, Hans-Peter; Kwa?niewski, Miros?aw; Chwia?kowska, Karolina; Chmielewska, Beata; Szarejko, Iwona
The appearance of hair plays an important role in people’s overall physical appearance and self-perception. With today’s increasing life-expectations, the desire to look youthful plays a bigger role than ever. The hair care industry has become aware of this and is delivering active products directed towards meeting this consumer demand. The discovery of pharmacological targets and the development of safe and effective drugs also indicate strategies of the drug industry for maintenance of healthy and beautiful hair. Hair aging comprises weathering of the hair shaft, decrease of melanocyte function, and decrease in hair production. The scalp is subject to intrinsic and extrinsic aging. Intrinsic factors are related to individual genetic and epigenetic mechanisms with interindividual variation: prototypes are familial premature graying, and androgenetic alopecia. Currently available pharmacologic treatment modalities with proven efficacy for treatment of androgenetic alopecia are topical minoxidil and oral finasteride. Extrinsic factors include ultraviolet radiation and air pollution. Experimental evidence supports the hypothesis that oxidative stress also plays a role in hair aging. Topical anti-aging compounds include photoprotectors and antioxidants. In the absence of another way to reverse hair graying, hair colorants remain the mainstay of recovering lost hair color. Topical liposome targeting for melanins, genes, and proteins selectively to hair follicles are currently under investigation.
Trueb, Ralph M
Background: Extensive researches are going on to explore the effective and safe drug for their hair growth. Tobacco leaves are traditionally known to potentiate hair growth promotion. Therefore, the aim of present study was to formulate and evaluate the microbial biotransformed extract of tobacco leaves for hair growth potential in male albino wister rats. Materials and Methods: The extract of was prepared by microbial biotransformation of tobacco leaves in cow urine for 28 days. The herbal formulations (lotion) were formulated by general method using o/w type base in various rations or concentrations such as 10%, 20% and 30% of extract. These lotions were applied on shaved skin area of rats for 30 days once in a day and hair length, serum total protein, and total testosterone were measured. Results: Our formulations show increase in hair growth and serum total protein at concentration dependent manner with effect to standard and control groups. Serum total testosterone decreases according to a concentration dependent manner. Conclusion: Further, series of investigations are, however, necessary to remain exploration, which includes their structural elucidation, characterization, clinical safety, reliability and molecular mechanism involved in this pharmacological activity.
Murkute, Ashlesh V.; Sahu, Mahesh S.; Mali, Prashant Y.; Rangari, Vinod D.
Perennial pasture species are important for sustainable pasture systems; yet some species display poor persistence on acid\\u000a soils. This work investigated the effect of soil acidity on primary root length and root-hair and rhizosheath development\\u000a of five perennial grass genotypes varying in acid-soil resistance. Plants were grown in three low-P acid soils that were limed\\u000a (CaCO3) to modify soil pH
Rebecca E. Haling; Alan E. Richardson; Richard A. Culvenor; Hans Lambers; Richard J. Simpson
The organ of Corti in the mammalian inner ear is comprised of mechanosensory hair cells (HCs) and nonsensory supporting cells (SCs), both of which are believed to be terminally postmitotic beyond late embryonic ages. Consequently, regeneration of HCs and SCs does not occur naturally in the adult mammalian cochlea, though recent evidence suggests that these cells may not be completely or irreversibly quiescent in at earlier postnatal ages. Furthermore, regenerative processes can be induced by genetic and pharmacological manipulations, but, more and more reports suggest that regenerative potential declines as the organ of Corti continues to age. In numerous mammalian systems, such effects of aging on regenerative potential are well established. However, in the cochlea, the problem of regeneration has not been traditionally viewed as one of aging. This is an important consideration as current models are unable to elicit widespread regeneration or full recovery of function at adult ages yet regenerative therapies will need to be developed specifically for adult populations. Still, the advent of gene targeting and other genetic manipulations has established mice as critically important models for the study of cochlear development and HC regeneration and suggests that auditory HC regeneration in adult mammals may indeed be possible. Thus, this review will focus on the pursuit of regeneration in the postnatal and adult mouse cochlea and highlight processes that occur during postnatal development, maturation, and aging that could contribute to an age-related decline in regenerative potential. Second, we will draw upon the wealth of knowledge pertaining to age related senescence in tissues outside of the ear to synthesize new insights and potentially guide future research aimed at promoting HC regeneration in the adult cochlea.
Walters, Brad; Zuo, Jian
This project will determine the critical factors that account for exposures to endocrine disrupting chemicals, or EDCs (ER, AR, AhR mediated and inhibitors of steroidogenesis) during development resulting in adverse effects seen later in life in male and female offspring. Such f...
MicroRNAs (miRNAs) inhibit the translation of target mRNAs and affect, directly or indirectly, the expression of a large portion of the protein-coding genes. This study focuses on miRNAs that are expressed in the mouse cochlea and vestibule, the 2 inner ear compartments. A conditional knock-out mouse for Dicer1 demonstrated that miRNAs are crucial for postnatal survival of functional hair cells of the inner ear. We identified miRNAs that have a role in the vertebrate developing inner ear by combining miRNA transcriptome analysis, spatial and temporal expression patterns, and bioinformatics. Microarrays revealed similar miRNA profiles in newborn-mouse whole cochleae and vestibules, but different temporal and spatial expression patterns of six miRNAs (miR-15a, miR-18a, miR-30b, miR-99a, miR-182, and miR-199a) may reflect their roles. Two of these miRNAs, miR-15a-1 and miR-18a, were also shown to be crucial for zebrafish inner ear development and morphogenesis. To suggest putative target mRNAs whose translation may be inhibited by selected miRNAs, we combined bioinformatics-based predictions and mRNA expression data. Finally, we present indirect evidence that Slc12a2, Cldn12, and Bdnf mRNAs may be targets for miR-15a. Our data support the hypothesis that inner ear tissue differentiation and maintenance are regulated and controlled by conserved sets of cell-specific miRNAs in both mouse and zebrafish. PMID:19416898
Friedman, Lilach M; Dror, Amiel A; Mor, Eyal; Tenne, Tamar; Toren, Ginat; Satoh, Takunori; Biesemeier, Deborah J; Shomron, Noam; Fekete, Donna M; Hornstein, Eran; Avraham, Karen B
Hair keratin is a composite structure in which intermediate filaments (IF) are embedded in a protein matrix. During the early stages of development in the hair follicle the redox potential is such that the cysteine residues in the IF are maintained in a reduced form. However, at a late stage of development the redox potential changes to produce an oxidizing environment and the IF undergo a structural transition involving both molecular slippage and radial compaction. In our earlier study the changes in the molecular parameters were estimated from knowledge of the sites of artificially induced crosslinks, and it was noted that the changes in these parameters realigned many of the cysteine residues to positions more favorable to disulfide bond formation. As the energy involved in the formation of disulfide bonds is much greater than that of hydrogen bonds or van der Waals interactions the structural transition is likely to be dominated by the requirement that the bonded cysteine residues occur at closely equivalent axial positions. This criterion was used in the present study to obtain more precise values for the molecular parameters in the oxidized fiber than has hitherto been possible. A comparison of the sequences of hair keratins and epidermal keratins suggests that the slippage observed in trichocyte IF during keratinization does not occur in epidermal IF. PMID:22683767
Bruce Fraser, R D; Parry, David A D
Cell culture studies have implicated the oxygen-sensitive hypoxia-inducible factor (HIF) prolyl hydroxylase PHD3 in the regulation of neuronal apoptosis. To better understand this function in vivo, we have created PHD3?/? mice and analyzed the neuronal phenotype. Reduced apoptosis in superior cervical ganglion (SCG) neurons cultured from PHD3?/? mice is associated with an increase in the number of cells in the SCG, as well as in the adrenal medulla and carotid body. Genetic analysis by intercrossing PHD3?/? mice with HIF-1a+/? and HIF-2a+/? mice demonstrated an interaction with HIF-2? but not HIF-1?, supporting the nonredundant involvement of a PHD3-HIF-2? pathway in the regulation of sympathoadrenal development. Despite the increased number of cells, the sympathoadrenal system appeared hypofunctional in PHD3?/? mice, with reduced target tissue innervation, adrenal medullary secretory capacity, sympathoadrenal responses, and systemic blood pressure. These observations suggest that the role of PHD3 in sympathoadrenal development extends beyond simple control of cell survival and organ mass, with functional PHD3 being required for proper anatomical and physiological integrity of the system. Perturbation of this interface between developmental and adaptive signaling by hypoxic, metabolic, or other stresses could have important effects on key sympathoadrenal functions, such as blood pressure regulation.
Bishop, Tammie; Gallagher, Denis; Pascual, Alberto; Lygate, Craig A.; de Bono, Joseph P.; Nicholls, Lynn G.; Ortega-Saenz, Patricia; Oster, Henrik; Wijeyekoon, Bhathiya; Sutherland, Andrew I.; Grosfeld, Alexandra; Aragones, Julian; Schneider, Martin; van Geyte, Katie; Teixeira, Dania; Diez-Juan, Antonio; Lopez-Barneo, Jose; Channon, Keith M.; Maxwell, Patrick H.; Pugh, Christopher W.; Davies, Alun M.; Carmeliet, Peter; Ratcliffe, Peter J.
Background: Male baldness develops because of an increased duration of the lag phase. Objective and Methods: To assess if this occurs also in balding women we studied 2 women with Ludwig type I–II patterned baldness for 2 years with monthly phototrichograms. Hairs were identified as thick anagen hairs, thin anagen hairs and telogen hairs. Results and Conclusions: Most of the
M. Guarrera; A. Rebora
We describe the effects of an absence of retinoic acid (RA) on the development of somites in the quail embryo. RA was removed by generating vitamin A deficient quail embryos whereupon the resulting defects in the embryos can be analysed. The effect on the somites is threefold. Firstly, they are half the size of normal, but the total number of somites is the same as normal. There has therefore been some global regulation event. Secondly, by TUNEL staining and TEM we show that the lateral halves of all of the somites undergo apoptosis between stages 11 and 14. This effect is confined to the sclerotome of the somites. Thirdly, some of the genes involved in somite differentiation are down-regulated such as fgf-4, fgf-8, engrailed and myogenin whereas others we examined such as cek-8, Delta, follistatin and myf5 are not affected. These studies reveal remarkably specific effects of RA on developmental gene pathways in the embryo. PMID:10761860
Maden, M; Graham, A; Zile, M; Gale, E
Autosomal recessive woolly hair/hypotrichosis (ARWH/H) is a nonsyndromic hair abnormality characterized by sparse, short and curly hair (WH/H). We report the case of a 3-year-old female, with no consanguineous ancestry, who exhibited WH/H. Normal hair was observed at birth, but severe hair loss had developed within the first 6 months; however, her hair density had improved somewhat by age 3. Light microscopy showed hair shaft invaginations, and polarized light microscopy suggested complete medullary disruption of the hair. Direct sequence analysis of peripheral blood showed a homozygous missense mutation in exon 6 of the lipase H gene (LIPH: c.736T>A, p.Cys246Ser), and the exact same mutation was found in the heterozygous state in both parents. The initial deterioration followed by improvement with age observed in this case suggests that the clinical course of ARWH/H may vary among patients with the same mutation in LIPH detected in this case, indicating that additional factors may influence the effect of LIPH on hair development.
Matsuno, Naoko; Kunisada, Makoto; Kanki, Haruhisa; Simomura, Yutaka; Nishigori, Chikako
Two brothers are described with athyroidal hypothyroidism, spiky hair, choanal atresia, cleft palate, and bifid epiglottis. Polyhydramnios was present in the third trimester of each pregnancy. These abnormalities appear to represent a new syndrome.
J S Bamforth; I A Hughes; J H Lazarus; C M Weaver; P S Harper
We used bright-field, time-lapse video, cross-polarized, phase-contrast, and fluorescence microscopies to examine the influence of isolated chitolipooligosaccharides (CLOSs) from wild-type Rhizobium leguminosarum bv. trifolii on development of white clover root hairs, and the role of these bioactive glycolipids in primary host infection. CLOS action caused a threefold increase in the differentiation of root epidermal cells into root hairs. At maturity, root hairs were significantly longer because of an extended period of active elongation without a change in the elongation rate itself. Time-series image analysis showed that the morphological basis of CLOS-induced root hair deformation is a redirection of tip growth displaced from the medial axis as previously predicted. Further studies showed several newly described infection-related root hair responses to CLOSs, including the localized disruption of the normal crystallinity in cell wall architecture and the induction of new infection sites. The application of CLOS also enabled a NodC- mutant of R. leguminosarum bv. trifolii to progress further in the infection process by inducing bright refractile spot modifications of the deformed root hair walls. However, CLOSs did not rescue the ability of the NodC- mutant to induce marked curlings or infection threads within root hairs. These results indicate that CLOS Nod factors elicit several host responses that modulate the growth dynamics and symbiont infectibility of white clover root hairs but that CLOSs alone are not sufficient to permit successful entry of the bacteria into root hairs during primary host infection in the Rhizobium-clover symbiosis.
Dazzo, F B; Orgambide, G G; Philip-Hollingsworth, S; Hollingsworth, R I; Ninke, K O; Salzwedel, J L
Background Notch signaling involves ligand-receptor interactions through direct cell-cell contact. Multiple Notch receptors and ligands are expressed in the epidermis and hair follicles during embryonic development and the adult stage. Although Notch signaling plays an important role in regulating differentiation of the epidermis and hair follicles, it remains unclear how Notch signaling participates in late-stage epidermal differentiation and postnatal hair cycle homeostasis. Methodology and Principal Findings We applied Cre/loxP system to generate conditional gene targeted mice that allow inactivation of critical components of Notch signaling pathway in the skin. Rbpj, the core component of all four Notch receptors, and Pofut1, an essential factor for ligand-receptor interactions, were inactivated in hair follicle lineages and suprabasal layer of the epidermis using the Tgfb3-Cre mouse line. Rbpj conditional inactivation resulted in granular parakeratosis and reactive epidermal hyperplasia. Pofut1 conditional inactivation led to ultrastructural abnormalities in the granular layer and altered filaggrin processing in the epidermis, suggesting a perturbation of the granular layer differentiation. Disruption of Pofut1 in hair follicle lineages resulted in aberrant telogen morphology, a decrease of bulge stem cell markers, and a concomitant increase of K14-positive keratinocytes in the isthmus of mutant hair follicles. Pofut1-deficent hair follicles displayed a delay in anagen re-entry and dysregulation of proliferation and apoptosis during the hair cycle transition. Moreover, increased DNA double stand breaks were detected in Pofut1-deficent hair follicles, and real time PCR analyses on bulge keratinocytes isolated by FACS revealed an induction of DNA damage response and a paucity of DNA repair machinery in mutant bulge keratinocytes. Significance our data reveal a role for Notch signaling in regulating late-stage epidermal differentiation. Notch signaling is required for postnatal hair cycle homeostasis by maintaining proper proliferation and differentiation of hair follicle stem cells.
Lin, Hsien-Yi; Kao, Cheng-Heng; Lin, Kurt Ming-Chao; Kaartinen, Vesa; Yang, Liang-Tung
\\u000a Root hairs are long tubular outgrowths of root epidermis cell that form to increase the root surface in order to assist in\\u000a the uptake of water and nutrients from soil. Root hair development consists of two distinct processes: root hair initiation\\u000a and tip growth. During both events, the dynamic organization of the cytoskeleton translates local signaling events into a\\u000a focused
Eunsook Park; Andreas Nebenführ
Presented for practitioners is a history of the development of abnormal psychology. Areas covered include the following: Early medical concepts, ideas carried over from literature, early treatment of the mentally ill, development of the psychological viewpoint, Freud's psychoanalytic theory, Jung's analytic theory, the individual psychology of…
Phelps, William R.
\\u000a Contact dermatitis to hair dye ingredients have been known since human started dyeing with aromatic amines like p-phenylenediamine\\u000a (PPD). Hair dye allergy may cause severe clinical reactions, with edema of the face, eyelids, and scalp. More moderate reactions\\u000a such as erythema, suppuration, and ulceration, typically at the scalp margin, on the ears, and sometimes with evidence of\\u000a eczema where the
David Basketter; Jeanne Duus Johansen; John McFadden; Heidi Søsted
Hereditary hypertrichoses are a group of hair overgrowth syndromes that are extremely rare in humans. We have previously demonstrated that a position effect on TRPS1 is associated with hypertrichosis in humans and mice. To gain insight into the functional role of Trps1, we analyzed the late morphogenesis vibrissae phenotype of Trps1?gt mutant mice, which is characterized by follicle degeneration after peg downgrowth has been initiated. We found that Trps1 directly represses expression of the hair follicle stem cell regulator Sox9 to control proliferation of the follicle epithelium. Furthermore, we identified a copy number variation upstream of SOX9 in a family with hypertrichosis that significantly decreases expression of the gene in the hair follicle, providing new insights into the long-range regulation of SOX9. Our findings uncover a novel transcriptional hierarchy that regulates epithelial proliferation in the developing hair follicle and contributes to the pathology of hypertrichosis.
Fantauzzo, Katherine A.; Kurban, Mazen; Levy, Brynn; Christiano, Angela M.
The management of disorders of sexual development (DSD) in humans and domestic animals has been the subject of intense interest for decades. The association between abnormal chromosome constitutions and DSDs in domestic animals has been recorded since the beginnings of conventional cytogenetic analysis. Deviated karyotypes consisting of abnormal sex chromosome sets and/or the coexistence of cells with different sex chromosome constitutions in an individual seem to be the main causes of anomalies of sex determination and sex differentiation. In recent years, a growing interest has developed around the environmental insults, such as endocrine-disrupting compounds (EDC) and heat stressors, which affect fertility, early embryonic development and, in some instances, directly the sex ratio and/or the development of 1 specific sex versus the other. A variety of chemical compounds present in the environment at low doses has been shown to have major effects on the reproductive functions in human and domestic animals following prolonged exposure. In this review, we present an overview of congenital/chromosomal factors that are responsible for the DSDs and link them and the lack of proper embryonic development to environmental factors that are becoming a major global concern. PMID:22024933
Favetta, L A; Villagómez, D A F; Iannuzzi, L; Di Meo, G; Webb, A; Crain, S; King, W A
The hypoxia-inducible factors HIF-1? or HIF-2? form heterodimeric complexes with the aryl hydrocarbon receptor nuclear translocator (ARNT). HIF-1?/ARNT and HIF-2?/ARNT complexes activate hypoxia-inducible genes that play critical roles in angiogenesis, anaerobic metabolism, and other processes in response to O2 deprivation. HIF-2? is known to regulate the function and/or differentiation of stem cells by activating the POU domain transcription factor Oct4; however, the precise underlying mechanism is unknown. This study examined the role of HIF-2?/ARNT in hair development using conditional-knockout mice, in which Arnt was specifically deleted in keratinocytes. In wild-type mice, HIF-2? and ARNT were highly expressed in the precortex above the hair matrix, an area containing differentiating stem cells. An analysis of hair size and type in these mice showed that loss of ARNT decreased the production of zigzag hairs, corresponding to reduced expression of HIF-2? and induction of the mammalian cyclin-dependent kinase inhibitors p21(Waf1/Cip1) and p27 (Kip1). The results suggest that the HIF-2?/ARNT complex regulates hair follicle differentiation via induction of p21(Waf1/Cip1) and possibly p27(Kip1), as p27(Kip1) expression was not altered in ARNT knockout mice. The findings provide insight into a possible mechanism underlying hair growth disorders and can be useful for future studies on hair follicle response to insults, such as chemotherapy and ionizing radiation.-Imamura, Y., Tomita, S., Imanishi, M., Kihira, Y., Ikeda, Y., Ishizawa, K., Tsuchiya, K., Tamaki, T. HIF-2?/ARNT complex regulates hair development via induction of p21(Waf1/Cip1) and p27(Kip1). PMID:24599965
Imamura, Yuko; Tomita, Shuhei; Imanishi, Masaki; Kihira, Yoshitaka; Ikeda, Yasumasa; Ishizawa, Keisuke; Tsuchiya, Koichiro; Tamaki, Toshiaki
Outer hair cells of the cultured organ of Corti from newborn rats (0–11 days after birth) were studied in the whole-cell\\u000a patch-clamp configuration. A voltage-activated sodium current was detected in 97% (n = 109) of the cells at 0–9 days after birth. The properties of this current were: (1) its activation and inactivation kinetics\\u000a were fast and voltage-dependent, (2) the
D. Oliver; P. Plinkert; H. P. Zenner; J. P. Ruppersberg
Root hairs are long tubular outgrowths that form on the surface of specialized epidermal cells. They are required for nutrient and water uptake and interact with the soil microflora. Here we show that the Oryza sativa cellulose synthase-like D1 (OsCSLD1) gene is required for root hair development, as rice (Oryza sativa) mutants that lack OsCSLD1 function develop abnormal root hairs. In these mutants, while hair development is initiated normally, the hairs elongate less than the wild-type hairs and they have kinks and swellings along their length. Because the csld1 mutants develop the same density and number of root hairs along their seminal root as the wild-type plants, we propose that OsCSLD1 function is required for hair elongation but not initiation. Both gene trap expression pattern and in situ hybridization analyses indicate that OsCSLD1 is expressed in only root hair cells. Furthermore, OsCSLD1 is the only member of the four rice CSLD genes that shows root-specific expression. Given that the Arabidopsis (Arabidopsis thaliana) gene KOJAK/AtCSLD3 is required for root hair elongation and is expressed in the root hair, it appears that OsCSLD1 may be the functional ortholog of KOJAK/AtCSLD3 and that these two genes represent the root hair-specific members of this family of proteins. Thus, at least part of the mechanism of root hair morphogenesis in Arabidopsis is conserved in rice.
Kim, Chul Min; Park, Sung Han; Je, Byoung Il; Park, Su Hyun; Park, Soon Ju; Piao, Hai Long; Eun, Moo Young; Dolan, Liam; Han, Chang-deok
As the most important natural raw material for textile industry, cotton fibres are an excellent model for studying single-cell development. Although expression profiling and functional genomics have provided some data, the mechanism of fibre development is still not well known. A class I TCP transcription factor (designated GbTCP), encoding 344 amino acids, was isolated from the normalized cDNA library of sea-island cotton fibre (from –2 to 25 days post anthesis). GbTCP was preferentially expressed in the elongating cotton fibre from 5 to 15 days post anthesis. Some expression was also observed in stems, apical buds, and petals. RNAi silencing of GbTCP produced shorter fibre, a reduced lint percentage, and a lower fibre quality than the wild-type plants. Overexpression of GbTCP enhanced root hair initiation and elongation in Arabidopsis and regulated branching. Solexa sequencing and Affymetrix GeneChip analysis indicated that GbTCP positively regulates the level of jasmonic acid (JA) and, as a result, activates downstream genes (reactive oxygen species, calcium signalling, ethylene biosynthesis and response, and several NAC and WRKY transcription factors) necessary for elongation of fibres and root hairs. JA content analysis in cotton also confirmed that GbTCP has a profound effect on JA biosynthesis. In vitro ovule culture showed that an appropriate concentration of JA promoted fibre elongation. The results suggest that GbTCP is an important transcription factor for fibre and root hair development by regulating JA biosynthesis and response and other pathways, including reactive oxygen species, calcium channel and ethylene signalling.
As the most important natural raw material for textile industry, cotton fibres are an excellent model for studying single-cell development. Although expression profiling and functional genomics have provided some data, the mechanism of fibre development is still not well known. A class I TCP transcription factor (designated GbTCP), encoding 344 amino acids, was isolated from the normalized cDNA library of sea-island cotton fibre (from -2 to 25 days post anthesis). GbTCP was preferentially expressed in the elongating cotton fibre from 5 to 15 days post anthesis. Some expression was also observed in stems, apical buds, and petals. RNAi silencing of GbTCP produced shorter fibre, a reduced lint percentage, and a lower fibre quality than the wild-type plants. Overexpression of GbTCP enhanced root hair initiation and elongation in Arabidopsis and regulated branching. Solexa sequencing and Affymetrix GeneChip analysis indicated that GbTCP positively regulates the level of jasmonic acid (JA) and, as a result, activates downstream genes (reactive oxygen species, calcium signalling, ethylene biosynthesis and response, and several NAC and WRKY transcription factors) necessary for elongation of fibres and root hairs. JA content analysis in cotton also confirmed that GbTCP has a profound effect on JA biosynthesis. In vitro ovule culture showed that an appropriate concentration of JA promoted fibre elongation. The results suggest that GbTCP is an important transcription factor for fibre and root hair development by regulating JA biosynthesis and response and other pathways, including reactive oxygen species, calcium channel and ethylene signalling. PMID:23105133
Hao, Juan; Tu, Lili; Hu, Haiyan; Tan, Jiafu; Deng, Fenglin; Tang, Wenxin; Nie, Yichun; Zhang, Xianlong
The rough coat (rc) spontaneous mutation causes sebaceous gland (SG) hypertrophy, hair loss, and extracutaneous abnormalities including growth retardation. The rc mice have a missense mutation in the predicted Ig protein Myelin Protein Zero-Like 3 (Mpzl3). In this study, we generated Mpzl3 knockout mice to determine its functions in the skin. Homozygous Mpzl3 knockout mice showed unkempt and greasy hair coat and hair loss soon after birth. Histological analysis revealed severe SG hypertrophy and increased dermal thickness, but did not detect significant changes in the hair cycle. Mpzl3-null mice frequently developed inflammatory skin lesions; however, the early-onset skin abnormalities were not the result of immune defects. The abnormalities in the Mpzl3 knockout mice closely resemble those observed in rc/rc mice, and in mice heterozygous for both the rc and Mpzl3 knockout alleles, indicating that rc and Mpzl3 are allelic. Using a lacZ reporter gene, we detected Mpzl3 promoter activity in the companion layer and inner root sheath of the hair follicle, SG, and epidermis. Loss of MPZL3 function also caused a striking reduction in cutaneous and overall adipose tissue. These data reveal a complex role for Mpzl3 in the control of skin development, hair growth, and adipose cell functions. PMID:24531688
Leiva, Angel G; Chen, Anne L; Devarajan, Priyadharshini; Chen, Zhibin; Damanpour, Shadi; Hall, Jessica A; Bianco, Antonio C; Li, Jie; Badiavas, Evangelos V; Zaias, Julia; Miteva, Mariya; Romanelli, Paolo; Nouri, Keyvan; Cao Wikramanayake, Tongyu
Although apparently phenotypically normal at birth, mice heterozygous for inactivation of the gene encoding parathyroid hormone-related peptide (PTHrP) develop haplotype insufficiency by 3 months of age. In addition to histologic and morphologic abnormalities similar to those seen in homozygous mutants, heterozygous animals demonstrated alterations in trabecular bone and bone marrow. These included metaphyseal bone spicules which were diminished in volume,
Norio Amizuka; Andrew C. Karaplis; Janet E. Henderson; Hershey Warshawsky; Mark L. Lipman; Yutaka Matsuki; Sadakazu Ejiri; Mikako Tanaka; Naoya Izumi; Hidehiro Ozawa; David Goltzman
Nuclear lamins are components of the nuclear lamina, a structural scaffolding for the cell nucleus. Defects in lamins A and C cause an array of human diseases, including muscular dystrophy, lipodystrophy, and progeria, but no diseases have been linked to the loss of lamins B1 or B2. To explore the functional relevance of lamin B2, we generated lamin B2-deficient mice and found that they have severe brain abnormalities resembling lissencephaly, with abnormal layering of neurons in the cerebral cortex and cerebellum. This neuronal layering abnormality is due to defective neuronal migration, a process that is dependent on the organized movement of the nucleus within the cell. These studies establish an essential function for lamin B2 in neuronal migration and brain development.
Coffinier, Catherine; Chang, Sandy Y.; Nobumori, Chika; Tu, Yiping; Farber, Emily A.; Toth, Julia I.; Fong, Loren G.; Young, Stephen G.
Briefly describes some of the more recent developments in the use of human hairs for such instructional purposes as observing barr bodies and chromosomes, and for culturing to produce cells of both epithelial and fibroblastic morphology. Three main hair categories are also described. (JN)
Human PITX2 mutations are associated with Axenfeld-Rieger syndrome, an autosomal-dominant developmental disorder that involves ocular anterior segment defects, dental hypoplasia, craniofacial dysmorphism and umbilical abnormalities. Characterization of the PITX2 pathway and identification of the mechanisms underlying the anomalies associated with PITX2 deficiency is important for better understanding of normal development and disease; studies of pitx2 function in animal models can facilitate these analyses. A knockdown of pitx2 in zebrafish was generated using a morpholino that targeted all known alternative transcripts of the pitx2 gene; morphant embryos generated with the pitx2ex4/5 splicing-blocking oligomer produced abnormal transcripts predicted to encode truncated pitx2 proteins lacking the third (recognition) helix of the DNA-binding homeodomain. The morphological phenotype of pitx2ex4/5 morphants included small head and eyes, jaw abnormalities and pericardial edema; lethality was observed at ?6–8-dpf. Cartilage staining revealed a reduction in size and an abnormal shape/position of the elements of the mandibular and hyoid pharyngeal arches; the ceratobranchial arches were also decreased in size. Histological and marker analyses of the misshapen eyes of the pitx2ex4/5 morphants identified anterior segment dysgenesis and disordered hyaloid vasculature. In summary, we demonstrate that pitx2 is essential for proper eye and craniofacial development in zebrafish and, therefore, that PITX2/pitx2 function is conserved in vertebrates.
Liu, Yi; Semina, Elena V.
Constructed wetlands are promoted for effectiveness at treating wastewater and potential value as wildlife habitat; however, wildlife performance studies in treated wastewater wetlands are limited. We used repeated surveys of larval amphibians along three wetland systems and four reference sites to test the hypothesis that bullfrog tadpoles exposed to direct inputs of treated wastewater develop slower, show a higher frequency of abnormalities, and are smaller at metamorphosis compared to tadpoles from reference ponds. Bullfrog tadpoles from wastewater wetlands were similar in size at metamorphosis compared to tadpoles from reference sites; however, they did show a much higher frequency of abnormalities including severe edema, scoliosis, and extreme calcinosis of soft tissues. Calcinosis was novel to the literature on amphibian abnormalities, the most frequent abnormality, and restricted exclusively to treatment wetlands. Within the constructed wetlands, tadpole development was slower and the frequency of scoliosis and calcinosis was higher in those cells receiving direct inputs of treated wastewater. Our results suggest that portions of constructed wetlands that directly receive treated wastewater may be poor amphibian habitat. PMID:20540544
Ruiz, Alina M; Maerz, John C; Davis, Andrew K; Keel, M Kevin; Ferreira, Andrew R; Conroy, Michael J; Morris, Lawrence A; Fisk, Aaron T
Male embryonic mice with mutations in the X-linked aristaless-related homeobox gene (Arx) developed with small brains due to suppressed proliferation and regional deficiencies in the forebrain. These mice also showed aberrant migration and differentiation of interneurons containing ?-aminobutyric acid (GABAergic interneurons) in the ganglionic eminence and neocortex as well as abnormal testicular differentiation. These characteristics recapitulate some of the clinical
Masako Yanazawa; Noriyuki Sugiyama; Hirohito Miura; Akiko Iizuka-Kogo; Masatomo Kusaka; Kayo Omichi; Rika Suzuki; Yuko Kato-Fukui; Kyoko Kamiirisa; Mina Matsuo; Shin-ichi Kamijo; Megumi Kasahara; Hidefumi Yoshioka; Tsutomu Ogata; Takayuki Fukuda; Ikuko Kondo; Mitsuhiro Kato; William B. Dobyns; Minesuke Yokoyama; Ken-ichirou Morohashi; Kunio Kitamura
Androgenetic alopecia affects both men and women. In men it produces male pattern hair loss with bitemporal recession and vertex baldness. In women it produces female pattern hair loss (FPHL) with diffuse alopecia over the mid-frontal scalp. FPHL occurs as a result of nonuniform hair follicle miniaturization within follicular units. Diffuse alopecia is produced by a reduction in the number of terminal fibres per follicular unit. Baldness occurs only when all hairs within the follicular units are miniaturized and is a relatively late event in women. The concepts of follicular units and primary and secondary hair follicles within follicular units are well established in comparative mammalian studies, particularly in sheep. However, discovery of these structures in the human scalp hair and investigation of the changes in follicular unit anatomy during the development of androgenetic alopecia have provided a clearer understanding of the early stages of androgenetic alopecia and how the male and female patterns of hair loss are related. FPHL is the most common cause of alopecia in women and approximately one-third of adult caucasian women experience hair loss. The impact of FPHL is predominantly psychological. While men anticipate age-related hair loss, hair loss in women is usually unexpected and unwelcome at any age. Treatment options to arrest hair loss progression and stimulate partial hair regrowth for FPHL include the androgen receptor antagonists spironolactone and cyproterone acetate, the 5?-reductase inhibitor finasteride and the androgen-independent hair growth stimulator minoxidil. These treatments appear to work best when initiated early. Hair transplantation should be considered in advanced FPHL that is resistant to medical treatments. Hair transplantation requires well-preserved hair growth over the occipital donor area. The psychological impact of FPHL may also be reduced by cosmetic products that improve the appearance of the hair. These agents work to minimize hair fibre breakage, improve hair volume or conceal visible bald scalp. PMID:22171680
Sinclair, R; Patel, M; Dawson, T L; Yazdabadi, A; Yip, L; Perez, A; Rufaut, N W
In this study the clinical data of all girls who visited the ambulance for paediatric and adolescent gynaecology at the university clinic for gynaecology and obstetrics in Vienna between 2001 and 2008 because of menstrual cycle abnormalities were used (n = 255). Most frequently, the girls suffered from dysmenorrhoea (29%), tempoanomaly (24%) and metrorrhagia (19%). For 57%, it was possible to find an underlying cause, mainly (24%) a hormonal one. The therapy was in 54% of all cases hormonal. In a second step, the study analyses matches between the age at menarche and the development of menstrual cycle abnormalities. Girls with primary amenorrhoea were excluded (n = 219). The study shows that every age of menarche has its special kind of menstrual cycle abnormality. Only if the menarche had set in at the age of 16, two kinds were named with equal frequency. PMID:20812052
Art, Mercedes Juliana; Doerfler, Daniela
While most commercially available functional near-infrared spectroscopy (fNIRS) systems employ optical fibers for both the measurement optode and the transmission cable for optical signals, their material inflexibility presents some problems in stable optode fixation to the head surface and adequate cable lining to the main system. In practice, mechanical fluctuations of optical fibers in fNIRS measurement often lead to motion artifacts in the signals. A few fiberless fNIRS systems are available and equipped with light sources and detectors that directly adhere to the scalp surface. However, their shapes and detection sensitivities are not suitable for usage on a hair-covered head. Based on the commercial fiber-less fNIRS system OEG-16 (Spectratech Inc., Japan), we developed a new source-detector unit that was designed with LEDs for enhanced illumination, avalanche photodiodes instead of photodiodes, and a new holder system. The electrical circuits of the system were modified after the design. By simultaneous implementation of multidistance fNIRS measurement and hemodynamic modality separation on conventional fNIRS data at the bilateral parietal area during single-sided motor tasks, significant functional signals were observed only at the position contralateral to the side of movement. This is the first report describing a fiber-less fNIRS system that can detect functional signals on a hair-covered head. We believe this fiber-less system will improve the utility of fNIRS, particularly in less restraining conditions.
Yamada, Toru; Ohashi, Mitsuo; Umeyama, Shinji
Context: Female pattern hair loss (FPHL) also known as female androgenetic alopecia is a common condition afflicting millions of women that can be cosmetically disrupting. Prompt diagnosis and treatment are essential for obtaining optimal outcome. This review addresses the clinical presentation of female pattern hair loss, its differential diagnosis and treatment modalities. Evidence Acquisition: A) Diffuse thinning of the crown region with preservation of the frontal hairline (Ludwig’s type) B) The “Christmas tree pattern” where the thinning is wider in the frontal scalp giving the alopecic area a triangular shaped figure resembling a christmas tree. C) Thinning associated with bitemporal recession (Hamilton type). Generally, FPHL is not associated with elevated androgens. Less commonly females with FPHL may have other skin or general signs of hyperandrogenism such as hirsutism, acne, irregular menses, infertility, galactorrhea and insulin resistance. The most common endocrinological abnormality associated with FPHL is polycystic ovarian syndrome (PCOS). Results: The most important diseases to consider in the differential diagnosis of FPHL include Chronic Telogen Effluvium (CTE), Permanent Alopecia after Chemotherapy (PAC), Alopecia Areata Incognito (AAI) and Frontal Fibrosing Alopecia (FFA). This review describes criteria for distinguishing these conditions from FPHL. Conclusions: The only approved treatment for FPHL, which is 2% topical Minoxidil, should be applied at the dosage of 1ml twice day for a minimum period of 12 months. This review will discuss off-label alternative modalities of treatment including 5-alfa reductase inhibitors, antiandrogens, estrogens, prostaglandin analogs, lasers, light treatments and hair transplantation.
Herskovitz, Ingrid; Tosti, Antonella
Background: Abnormal brain development due to neurodevelopmental disorders in children has always been an important concern, but yet has to be considered as a significant public health problem, especially in the low- and middle-income countries including Nigeria. Aims: The aim of this study is to determine whether abnormal brain development in the form of neurodevelopmental disorders causes any deviation in the cranial index of affected children. Materials and Methods: This is a comparative study on the head length, head width, and cranial index of 112 children (72 males and 40 females) diagnosed with at least one abnormal problem in brain development, in the form of a neurodevelopmental disorder (NDD), in comparison with that of 218 normal growing children without any form of NDD (121 males and 97 females), aged 0-18 years old seen at the Usmanu Danfodiyo University Teaching Hospital, Sokoto, over a period of six months, June to December, 2012. The head length and head width of the children was measured using standard anatomical landmarks and cranial index calculated. The data obtained was entered into the Microsoft excel worksheet and analyzed using SPSS version 17. Results: The mean Cephalic Index for normal growing children with normal brain development was 79.82 ± 3.35 and that of the children with abnormal brain development was 77.78 ± 2.95 and the difference between the two groups was not statistically significant (P > 0.05). Conclusion: It can be deduced from this present study that the cranial index does not change in children with neurodevelopmental disorders.
Musa, Muhammad Awwal; Zagga, Abdullahi Daudu; Danfulani, Mohammed; Tadros, Aziz Abdo; Ahmed, Hamid
Integral hair lipid (IHL) is bound to the keratinized cell surface to make an environmentally resistant lipid envelope. It is mainly positioned on the hair cuticle and inner root sheath. IHL in the hair follicle may regard as hair barrier to be similar to the epidermal lipid layer functioning as skin barrier. Major constituents of IHL are fatty acid, phytosphingosine,
A T-DNA insertional mutant OsAPC6 of rice, with gibberellic acid insensitivity and reduced height, had up to 45% reduced seed set. The insertion occurred on chromosome 3 of rice in the gene encoding one of the subunits of anaphase promoting complex/Cyclosome APC6. The primary mother cells of the mutant plants had normal meiosis, male gametophyte development and pollen viability. Confocal laser scanning microscopic (CLSM) studies of megagametophyte development showed abnormal mitotic divisions with reduced number or total absence of polar nuclei in about 30-35% megagametophytes of OsAPC6 mutant leading to failure of endosperm and hence embryo and seed development. Abnormal female gametophyte development, high sterility and segregation of tall and gibberellic acid sensitive plants without selectable marker Hpt in the selfed progeny of OsAPC6 mutant plants indicate that the mutant could be maintained in heterozygous condition. The abnormal mitotic divisions during megagametogenesis could be attributed to the inactivation of the APC6/CDC16 of anaphase promoting complex of rice responsible for cell cycle progression during megagametogenesis. Functional validation of the candidate gene through transcriptome profiling and RNAi is in progress. PMID:22195590
Awasthi, Anjali; Paul, Priyanka; Kumar, Satish; Verma, Shailendra Kumar; Prasad, R; Dhaliwal, H S
Target of rapamycin (TOR) was first identified in yeast as a target molecule of rapamycin, an anti-fugal and immunosuppressant macrolide compound. In mammals, its orthologue is called mammalian TOR (mTOR). mTOR is a serine/threonine kinase that converges different extracellular stimuli, such as nutrients and growth factors, and diverges into several biochemical reactions, including translation, autophagy, transcription, and lipid synthesis among others. These biochemical reactions govern cell growth and cause cells to attain an anabolic state. Thus, the disruption of mTOR signaling is implicated in a wide array of diseases such as cancer, diabetes, and obesity. In the central nervous system, the mTOR signaling cascade is activated by nutrients, neurotrophic factors, and neurotransmitters that enhances protein (and possibly lipid) synthesis and suppresses autophagy. These processes contribute to normal neuronal growth by promoting their differentiation, neurite elongation and branching, and synaptic formation during development. Therefore, disruption of mTOR signaling may cause neuronal degeneration and abnormal neural development. While reduced mTOR signaling is associated with neurodegeneration, excess activation of mTOR signaling causes abnormal development of neurons and glia, leading to brain malformation. In this review, we first introduce the current state of molecular knowledge of mTOR complexes and signaling in general. We then describe mTOR activation in neurons, which leads to translational enhancement, and finally discuss the link between mTOR and normal/abnormal neuronal growth during development.
Takei, Nobuyuki; Nawa, Hiroyuki
Contact allergy to hair dye ingredients, especially precursors and couplers, is a well-known entity among consumers having hair colouring done at home or at a hairdresser. The aim of the present investigation was to estimate consumer exposure to some selected precursors (p-phenylenediamine, toluene-2,5-diamine) and couplers (3-aminophenol, 4-aminophenol, resorcinol) of oxidative hair dyes during and after hair dyeing. Concentrations of unconsumed precursors and couplers in 8 hair dye formulations for non-professional use were investigated, under the conditions reflecting hair dyeing. Oxidative hair dye formation in the absence of hair was investigated using 6 products, and 2 products were used for experimental hair dyeing. In both presence and absence of hair, significant amounts of unconsumed precursors and couplers remained in the hair dye formulations after final colour development. Thus, up to 1.1% p-phenylenediamine (PPD), 0.04% toluene-2,5-diamine, 0.02% 3-aminophenol and 0.02% resorcinol were found in the hair dye formulation after the required colour was developed. The consumers are thus exposed to precursors and couplers of oxidative hair dyes, both during and after hair dyeing, when the hair is washed. Furthermore, the consumers are also expected to be exposed to intermediates of oxidative hair dyes. The allergenic potential of oxidative hair dyes as well as the intermediates of these remains unknown. PMID:16930234
Rastogi, Suresh Chandra; Søsted, Heidi; Johansen, Jeanne Duus; Menné, Torkil; Bossi, Rossana
Most common forms of hair loss (alopecia) are caused by aberrant hair follicle cycling and changes in hair follicle morphology. However, current treatments for alopecia do not specifically target these processes. We are now beginning to identify the molecules and molecular pathways that control normal hair follicle formation, cycling and growth. In parallel, new techniques are being developed for delivering
George Cotsarelis; Sarah E Millar
Background Genetic and environmental risk factors and gene-environment interactions are linked to higher likelihood of developing schizophrenia in accordance with the neurodevelopmental model of disease; little is known about risk factors and early development in early-onset schizophrenia (EOS) and very early-onset schizophrenia (VEOS). Methods We present a case-control study of a sample of 21 patients with EOS/VEOS and a control group of 21 patients with migraine, recruited from the Child Neuropsychiatry Unit, Department of Neurologic and Psychiatric Science, University of Bari, Italy. The aim was to assess the statistical association between VEOS/EOS and family history for psychiatric disorders, obstetric complications and childhood developmental abnormalities using 2 × 2 tables and a Chi Squared or Fisher test. Results The results show a statistical association between EOS/VEOS and schizophrenia and related disorders (P = 0.02) and personality disorders (P = 0.003) in relatives, and between EOS/VEOS and developmental abnormalities of early relational skills (P = 0.008) and learning (P = 0.04); there is not a statistically relevant difference between cases and controls (P > 0.05) for any obstetric complications (pre, peri and postpartum). Conclusions This study confirms the significant role of familial liability but not of obstetric complications in the pathogenesis of VEOS/EOS; the association between childhood developmental abnormalities and EOS/VEOS supports the neurodevelopmental model of disease.
A screen for protein tyrosine phosphatases (PTPs) expressed in the chick inner ear yielded a high proportion of clones encoding an avian ortholog of protein tyrosine phosphatase receptor Q (Ptprq), a receptor-like PTP. Ptprq was first identified as a transcript upregulated in rat kidney in response to glomerular nephritis and has recently been shown to be active against inositol phospholipids. An antibody to the intracellular domain of Ptprq, anti-Ptprq, stains hair bundles in mice and chicks. In the chick ear, the distribution of Ptprq is almost identical to that of the 275 kDa hair-cell antigen (HCA), a component of hair-bundle shaft connectors recognized by a monoclonal antibody (mAb) that stains inner-ear hair bundles and kidney glomeruli. Furthermore, anti-Ptprq immunoblots a 275 kDa polypeptide immunoprecipitated by the anti-HCA mAb from the avian inner ear, indicating that the HCA and Ptprq are likely to be the same molecule. In two transgenic mouse strains with different mutations in Ptprq, anti-Ptprq immunoreactivity cannot be detected in the ear. Shaft connectors are absent from mutant vestibular hair bundles, but the stereocilia forming the hair bundle are not splayed, indicating that shaft connectors are not necessary to hold the stereocilia together; however, the mice show rapid postnatal deterioration in cochlear hair-bundle structure, associated with smaller than normal transducer currents with otherwise normal adaptation properties, a progressive loss of basal-coil cochlear hair cells, and deafness. These results reveal that Ptprq is required for formation of the shaft connectors of the hair bundle, the normal maturation of cochlear hair bundles, and the long-term survival of high-frequency auditory hair cells. PMID:14534255
Goodyear, R J; Legan, P K; Wright, M B; Marcotti, W; Oganesian, A; Coats, S A; Booth, C J; Kros, C J; Seifert, R A; Bowen-Pope, D F; Richardson, G P
Stereocilia are specialized actin-filled, finger-like processes arrayed in rows of graded heights to form a crescent or W-shape on the apical surface of sensory hair cells. The stereocilia are deflected by the vibration of sound, which opens transduction channels and allows an influx of ions to depolarize the hair cell, in turn triggering synaptic activity. The specialized morphology and organization of the stereocilia bundle is crucial in the process of sensory transduction in the inner ear. However, we know little about the development of stereocilia in the mouse and few molecules that are involved in stereocilia maturation are known. We describe here a new mouse mutant with abnormal stereocilia development. The Tasmanian devil (tde) mouse mutation arose by insertional mutagenesis and has been mapped to the middle of chromosome 5. Homozygotes show head-tossing and circling and have raised thresholds for cochlear nerve responses to sound. The gross morphology of the inner ear was normal, but the stereocilia of cochlear and vestibular hair cells are abnormally thin, and they become progressively disorganized with increasing age. Ultimately, the hair cells die. This is the first report of a mutant showing thin stereocilia. The association of thin stereocilia with cochlear dysfunction emphasizes the critical role of stereocilia in auditory transduction, and the discovery of the Tasmanian devil mutant provides a resource for the identification of an essential molecule in hair cell function. PMID:12405956
Erven, Alexandra; Skynner, Michael J; Okumura, Katsuzumi; Takebayashi, Shin-ichiro; Brown, Steve D M; Steel, Karen P; Allen, Nicholas D
Background Children whose mothers consumed alcohol during pregnancy exhibit widespread brain abnormalities and a complex array of behavioral disturbances. Here, we used a mouse model of fetal alcohol exposure to investigate relationships between brain abnormalities and specific behavioral alterations during adulthood. Results Mice drank a 10% ethanol solution throughout pregnancy. When fetal alcohol-exposed offspring reached adulthood, we used high resolution MRI to conduct a brain-wide screen for structural changes and found that the largest reduction in volume occurred in the olfactory bulbs. Next, we tested adult mice in an associative olfactory task and found that fetal alcohol exposure impaired discrimination between similar odors but left odor memory intact. Finally, we investigated olfactory bulb neurogenesis as a potential mechanism by performing an in vitro neurosphere assay, in vivo labeling of new cells using BrdU, and in vivo labeling of new cells using a transgenic reporter system. We found that fetal alcohol exposure decreased the number of neural precursor cells in the subependymal zone and the number of new cells in the olfactory bulbs during the first few postnatal weeks. Conclusions Using a combination of techniques, including structural brain imaging, in vitro and in vivo cell detection methods, and behavioral testing, we found that fetal alcohol exposure results in smaller olfactory bulbs and impairments in odor discrimination that persist into adulthood. Furthermore, we found that these abnormalities in olfactory bulb structure and function may arise from deficits in the generation of new olfactory bulb neurons during early postnatal development.
The fate of the hair follicle pigmentary unit during the cyclical involution of anagen hair follicles is unknown. Using the C57BL\\/6 mouse model for hair research, hair follicle melanocytes were examined during the anagen–catagen transformation, comparing spontaneous and pharmacologically induced catagen development. This study shows that both spontaneous catagen and dexamethasone-induced catagen display similar changes in the pigmentary unit. Catagen
Desmond J. Tobin; Evelin Hagen; Vladimir A. Botchkarev; Ralf Paus
Root hairs are single cells specialized in the absorption of water and nutrients from the soil. Growing root hairs require intensive cell-wall changes to accommodate cell expansion at the apical end by a process known as tip or polarized growth. We have recently shown that cell wall glycoproteins such as extensins (EXTs) are essential components of the cell wall during polarized growth. Proline hydroxylation, an early posttranslational modification of cell wall EXTs that is catalyzed by prolyl 4-hydroxylases (P4Hs), defines the subsequent O-glycosylation sites in EXTs. Biochemical inhibition or genetic disruption of specific P4Hs resulted in the blockage of polarized growth in root hairs. Our results demonstrate that correct hydroxylation and also further O-glycosylation on EXTs are essential for cell-wall self-assembly and, hence, root hair elongation. The changes that O-glycosylated cell-wall proteins like EXTs undergo during cell growth represent a starting point to unravel the entire biochemical pathway involved in plant development.
Velasquez, Silvia M; Iusem, Norberto D
The hair-colours of an unselected Vienese sample (8399 male, 8176 female) of all ages and ascertained by the author himself have been analysed with regard to their sexual distribution. The comparisons of the age-groups necessary because of the individual age-changes of the hair-colour did not reveal any significant sexual dimorphism. Only during the periods of intensified growth the girls show a slight tendency to darker hair than the boys at the same age because of their faster development. PMID:921225
The developing human brain remains one of the few unsolved mysteries of science. Advancements in developmental biology, neuroscience, and medical imaging have brought us closer than ever to understand brain development in health and disease. However, the precise role of mechanics throughout this process remains underestimated and poorly understood. Here we show that mechanical stretch plays a crucial role in brain development. Using the nonlinear field theories of mechanics supplemented by the theory of finite growth, we model the human brain as a living system with a morphogenetically growing outer surface and a stretch-driven growing inner core. This approach seamlessly integrates the two popular but competing hypotheses for cortical folding: axonal tension and differential growth. We calibrate our model using magnetic resonance images from very preterm neonates. Our model predicts that deviations in cortical growth and thickness induce morphological abnormalities. Using the gyrification index, the ratio between the total and exposed surface area, we demonstrate that these abnormalities agree with the classical pathologies of lissencephaly and polymicrogyria. Understanding the mechanisms of cortical folding in the developing human brain has direct implications in the diagnostics and treatment of neurological disorders, including epilepsy, schizophrenia, and autism.
Budday, Silvia; Raybaud, Charles; Kuhl, Ellen
The developing human brain remains one of the few unsolved mysteries of science. Advancements in developmental biology, neuroscience, and medical imaging have brought us closer than ever to understand brain development in health and disease. However, the precise role of mechanics throughout this process remains underestimated and poorly understood. Here we show that mechanical stretch plays a crucial role in brain development. Using the nonlinear field theories of mechanics supplemented by the theory of finite growth, we model the human brain as a living system with a morphogenetically growing outer surface and a stretch-driven growing inner core. This approach seamlessly integrates the two popular but competing hypotheses for cortical folding: axonal tension and differential growth. We calibrate our model using magnetic resonance images from very preterm neonates. Our model predicts that deviations in cortical growth and thickness induce morphological abnormalities. Using the gyrification index, the ratio between the total and exposed surface area, we demonstrate that these abnormalities agree with the classical pathologies of lissencephaly and polymicrogyria. Understanding the mechanisms of cortical folding in the developing human brain has direct implications in the diagnostics and treatment of neurological disorders, including epilepsy, schizophrenia, and autism. PMID:25008163
Budday, Silvia; Raybaud, Charles; Kuhl, Ellen
Pili anulati are defined by characteristic alternating light and dark banding in the hair shaft, due to air-filled spaces between the macrofibrillar units of the hair cortex, and are regarded as a congenital hair shaft disorder without increased hair fragility. Two cases of pili anulati are presented, in which fragility of hair developed in a causal relationship with the onset
Günther F. L. Hofbauer; Dionysios Tsambaos; Max A. Spycher; Ralph M. Trüeb
Somatic cell nuclear transfer to an enucleated oocyte is used for reprogramming somatic cells with the aim of achieving totipotency, but most cloned embryos die in the uterus after transfer. While modifying epigenetic states of cloned embryos can improve their development, the production rate of cloned embryos can also be enhanced by changing other factors. It has already been shown that abnormal chromosome segregation (ACS) is a major cause of the developmental failure of cloned embryos and that Latrunculin A (LatA), an actin polymerization inhibitor, improves F-actin formation and birth rate of cloned embryos. Since F-actin is important for chromosome congression in embryos, here we examined the relation between ACS and F-actin in cloned embryos. Using LatA treatment, the occurrence of ACS decreased significantly whereas cloned embryo-specific epigenetic abnormalities such as dimethylation of histone H3 at lysine 9 (H3K9me2) could not be corrected. In contrast, when H3K9me2 was normalized using the G9a histone methyltransferase inhibitor BIX-01294, the Magea2 gene—essential for normal development but never before expressed in cloned embryos—was expressed. However, this did not increase the cloning success rate. Thus, non-epigenetic factors also play an important role in determining the efficiency of mouse cloning.
Terashita, Yukari; Yamagata, Kazuo; Tokoro, Mikiko; Itoi, Fumiaki; Wakayama, Sayaka; Li, Chong; Sato, Eimei; Tanemura, Kentaro; Wakayama, Teruhiko
To develop more effective oxidative hair coloring products, it is important to understand the localization of colored chromophores, which are formed from oxidative dyes, in the fine structure of hair. However, the dyeing regions of oxidative hair dyes in the fine structure of hair have not been extensively examined. In this study, we investigated the distribution and localization of colored chromophores formed by an oxidative hair coloring product in the fine structure of human hair by using a stable isotope-labeled oxidative dye with nanoscale secondary ion mass spectrometry (NanoSIMS). First, formation of the colored chromophore from a deuterium-labeled oxidative dye was examined by visible spectra similarly to a study of its formation using nonlabeled oxidative dye. Furthermore, the formation of binuclear indo dye containing deuterium in its chemical structure was confirmed using time-of-flight secondary ion mass spectrometry (TOF-SIMS) analysis. As a result of the NanoSIMS image on a cross-sectional dyed hair, although deuterium ions were detected in whole hair cross-section, quite a few of them were detected at particulate regions. These particulate regions of the dyed black hair in which deuterium ions were intensely detected were identified as melanin granules, by comparing the dyeing behaviors of black and white hair. NanoSIMS analysis revealed that melanin granules of black human hair are important dyeing regions in oxidative hair coloring. PMID:23434703
Kojima, Toru; Yamada, Hiromi; Yamamoto, Toshihiko; Matsushita, Yasuyuki; Fukushima, Kazuhiko
SUMMARY Disruption of the c-Kit\\/stem cell factor (SCF) signaling pathway interferes with the survival, migration, and differentiation of melanocytes during generation of the hair follicle pigmentary unit. We examined c-Kit, SCF, and S100 (a marker for precursor melanocytic cells) expression, as well as melanoblast\\/melanocyte ultrastructure, in perinatal C57BL\\/6 mouse skin. Before the onset of hair bulb melanogenesis (i.e., stages 0-4
Eva M. J. Peters; Desmond J. Tobin; Natasha Botchkareva; Marcus Maurer; Ralf Paus
A new test method has been developed to determine surface energy of hair fibers through measurements of contact angles at two hair/liquid interfaces. By measuring changes in surface energy of the same hair fiber before and after a cosmetic treatment, effects of active ingredients and the performance of tested formulations can be evaluated.The establishment of the method is based on Fowkes theory (1,2) described with two components, a dispersive and a non-dispersive component. The non-polar liquid used in this study was diiodomethane, and the polar liquid was benzyl alcohol. A Kruss 100 Tensiometer was used to measure contact angles of hair fibers. Virgin dark brown and regular bleached hairs were treated with selected conditioner formulations. Reductions in combing forces of hair tresses before and after respective treatments were correlated with decreases in average surface energy of hair fibers obtained from the corresponding tresses.Experimental results indicate that the average surface energy of hair fibers treated with conditioners decreases and the hydrophobicity of the hair surface increases, the results correlate well with the reduction in combing forces after respective treatments. This research work provides a new methodology to evaluate/screen conditioning performance of hair care ingredients and formulations for development of better products. PMID:21635842
Gao, Timothy; He, Yingxia; Landa, Peter; Tien, Jung-Mei
In this article, the nail, hair, and pigment changes caused by systemic diseases will be reviewed. Among the subjects discussed are abnormalities of shape, attachments, surface, and color of the nails; hair alterations such as telogen and anagen effluvium, scarring alopecia, hypertrichosis, and hirsutism; and pigment changes due to connective tissue disorders, sarcoidosis, and metabolic and endocrinologic diseases, among others.
Marcia Ramos-e-Silva; Melissa Chaves Azevedo-e-Silva; Sueli Coclho Carneiro
Background Tumors of the hypothalamic-pituitary unit have been linked to genetic syndromes that are associated with midfacial abnormalities. Aim We hypothesized that mutations of genes that affect the development of the face (and consequently of the anterior pituitary) may be present in children with ACTH-producing pituitary adenomas, and if this is true then facial measurements would be different from those predicted by parental features. Methods We studied 20 children with cortico-tropinomas and a control group and their parents. All facial measurements were expressed according to standard deviation scores. Results Significant differences were seen between the children with pituitary adenomas and their parents for vertical facial height measures: nasal length (p <0.001), lower facial height (p <0.03) and overall facial height (p <0.01). Conclusion We conclude that some of the indices of midline craniofacial development, in particular those affecting the vertical axis, are different in children with corticotroph adenomas producing ACTH.
Keil, Margaret F.; Stratakis, Constantine A.
Key tool of Redken Laboratories new line of hair styling appliances is an instrument called a thermograph, a heat sensing device originally developed by Hughes Aircraft Co. under U.S. Army and NASA funding. Redken Laboratories bought one of the early models of the Hughes Probeye Thermal Video System or TVS which detects the various degrees of heat emitted by an object and displays the results in color on a TV monitor with colors representing different temperatures detected.
The avian embryonic eye is used as a model system for studies on the environmental effects on central nervous system development. Here we present results of qualitative investigation of the eye development in quail embryos incubated in micro-"g" environment. In this study we used eyes of Japanese quail (Coturnix coturnix Japonica) embryos "flown" onboard biosatellite Kosmos-1129 and on Mir station within the framework of Mir-NASA Program. Eyes obtained from embryos ranging in age from 3-12 days (E3-E12) were prepared histologically and compared with those of the synchronous and laboratory gound controls. Ther most careful consideration was given to finding and analysis of eye developmental abnormalities. Then they were compared with those already described by experimental teratology for birds and mammals. At the stage of the "eye cup" (E3) we found the case of invalid formation of the inner retina. The latter was represented by disorganized neuroblasts occupying whole posterior chamber of the eye. On the 7th day of quail eye development, at the period of cellular growth activation some cases of small eyes with many folds of overgrowing neural and pigmented retinal layers were detected. In retinal folds of these eyes the normal layering was disturbed as well as the formation of aqueous body and pecten oculi. At this time point the changes were also found in the anterior part of the eye. The peculiarities came out of the bigger width of the cornea and separation of its layers, but were found in synchronous control as well. Few embryos of E10 had also eyes with the abnormities described for E7 but this time they were more vivid because of the completion of eye tissue differentiation. At the stage E12 we found the case evaluated as microphthalmia attending by overgrowth of anterior pigmented tissues - iris and ciliary body attached with the cornea. Most, but not all, of abnormalities we found in eye morphogeneses belonged to the birds "flown" aboard Kosmos- 1129 and were likely induced by specific conditions of that flight. All sorts of disturbances we observed in eye development were similar with dom inated types found in birds and mammals on ground and could be induced by factors we intend to discuss in our report.
Grigoryan, E.; Dadheva, O.; Polinskaya, V.; Guryeva, T.
The majority of cortical and hippocampal interneurons originate in the subcortical telencephalon and migrate tangentially into pallial regions before settling in various cortical layers. The molecular cues that regulate final positioning of specific interneurons in cortical structures have not yet been identified. The positioning of radially migrating principal neurons of the cortex and hippocampus depends upon Reelin, an extracellular protein expressed near the pial surface during embryonic development that is absent in reeler mutant mice. To determine whether the layer specification of interneurons, like that of principal neurons, requires Reelin, we crossed reeler with transgenic mice that contain Green Fluorescent Protein (GFP)-expressing Inhibitory Neurons (GINs). These neurons express basal forebrain markers Dlx1/2 in normal and reeler mice. In normal mice, GINs express Reelin and are localized to specific layers of the cortex and hippocampus. In reeler mutant mice, we show that GINs migrate normally into the pallium, but fail to acquire proper layer position. Double labeling experiments indicate that the neurochemical profile of these interneurons is not generally altered in reeler mice. However, the extension of their cellular processes is abnormal. Quantitative analysis of GINs in the cortex revealed that they are hypertrophic, bearing longer neuritic branches than normal. Thus, the lack of Reelin signaling results in abnormal positioning and altered morphology of forebrain interneurons. PMID:16996039
Yabut, Odessa; Renfro, Amy; Niu, Sanyong; Swann, John W; Marín, Oscar; D'Arcangelo, Gabriella
Lissencephaly is a relatively common brain malformation. Lissencephaly type 1 is characterized by the smooth appearance of the cortex and the presence of four abnormally positioned layers instead of the normal six. Lissencephaly is considered to be an abnormality in neuronal migration. The gene mutated in type 1 lissencephaly was cloned by us and designated LIS1. Recently, several genes involved in cortical development have been cloned in the mouse. In human an additional X-linked lissencephaly gene has been identified. We summarize here our current knowledge on the LIS1 gene and its function. It has been identified as a non-catalytic subunit of PAF-acetylhydrolase, a heterotrimeric enzyme which inactivates the platelet-activating factor (PAF). In addition, we have demonstrated that LIS1 interacts with tubulin, and affects the dynamics properties of microtubles. LIS1 contains seven WD repeats and may structurally resemble the beta-subunit of heterotrimeric G proteins. Interestingly, the catalytic subunit of PAF-acetylhydrolase was found to resemble the alpha subunit of heterotrimeric G proteins. We raise the possibility that LIS1 is part of an intracellular signaling pathway involved in neuronal migration. PMID:9852306
Reiner, O; Sapir, T
For analysis of hair samples derived from a pilot study ('in vivo' contamination of hair by sidestream marijuana smoke), an LC-MS/MS method was developed and validated for the simultaneous quantification of ?9-tetrahydrocannabinolic acid A (THCA-A), ?9-tetrahydrocannabinol (THC), cannabinol (CBN) and cannabidiol (CBD). Hair samples were extracted in methanol for 4 h under occasional shaking at room temperature, after adding THC-D(3), CBN-D(3), CBD-D(3) and THCA-A-D(3) as an in-house synthesized internal standard. The analytes were separated by gradient elution on a Luna C18 column using 0.1% HCOOH and ACN?+?0.1% HCOOH. Data acquisition was performed on a QTrap 4000 in electrospray ionization-multi reaction monitoring mode. Validation was carried out according to the guidelines of the German Society of Toxicological and Forensic Chemistry (GTFCh). Limit of detection and lower limit of quantification were 2.5 pg/mg for THCA-A and 20 pg/mg for THC, CBN and CBD. A linear calibration model was applicable for all analytes over a range of 2.5 pg/mg or 20 pg/mg to 1000 pg/mg, using a weighting factor 1/x. Selectivity was shown for 12 blank hair samples from different sources. Accuracy and precision data were within the required limits for all analytes (bias between -0.2% and 6.4%, RSD between 3.7% and 11.5%). The dried hair extracts were stable over a time period of one to five days in the dark at room temperature. Processed sample stability (maximum decrease of analyte peak area below 25%) was considerably enhanced by adding 0.25% lecithin (w/v) in ACN?+?0.1% HCOOH for reconstitution. Extraction efficiency for CBD was generally very low using methanol extraction. Hence, for effective extraction of CBD alkaline hydrolysis is recommended. PMID:23378095
Roth, Nadine; Moosmann, Bjoern; Auwärter, Volker
A new two-point bending stiffness method on flat hair strands was developed and validated after application of hair styling gels and hair styling sprays. A special mold was used to align single hair fibers after applying the formulations to the hair. The styling gels used contain different commercially available thickeners and styling polymers, e.g., carbomer, acrylates/beheneth-25 methacrylate copolymer, Polyquaternium-86, PVP, VP/VA copolymers, and VP/methacrylamide/vinylimidazole copolymer. Evaluation of hair sprays was performed after spray application on flat hair strands. Commercially available hair styling resins were used, e.g. acrylates/t-butylacrylamide copolymer, octylacrylamide/acrylates/butylaminoethyl methacrylate copolymer, and VP/VA copolymer (30:70). The new stiffness test method provided the best correlation with practically relevant sensory assessments on hair strands and a panel test in which styling gels were evaluated. However, we did not observe a correlation between the new stiffness method on flat hair strands and practical assessments in hair spray application. We postulate that different polymer/hair composites are responsible for these discrepancies. Hairs on model heads for half-side testing are spot-welded after spray application, while hairs are seam-welded in the stiffness test after alignment of single hair fibers. This alignment is necessary to achieve reproducible results. PMID:20939974
Hoessel, Peter; Riemann, Solveig; Knebl, Robert; Schroeder, Jens; Schuh, Gerd; Castillo, Catalina
A sensitive, specific and reproducible method for the quantitative determination of nandrolone in human hair has been developed. The sample preparation involved a decontamination step of the hair with methylene chloride. The hair sample (about 100 mg) was solubilized in 1 ml NaOH IN, 15 min at 95°C, in presence of 10 ng nandrolone-d3 used as an internal standard. The
P. Kintz; V. Cirimele; V. Dumestre-Toulet; B. Ludes
Hair follicle is an appendage organ of the skin which is of importance to the survival of mammals and still maintains significance for the human race - not just biologically, but also through cosmetic and commercial considerations. However data on composition of hair follicles are scarce and mostly limited to the hair shaft. In this study we provide detailed information on the elemental distribution in human hair follicles in different growth phases (anagen and catagen) using a scanning proton microprobe. The analysis of skin samples obtained from human adults undergoing plastic surgery and of organ-cultured human hair follicles may yield a new insight into the function, development and cyclic activity of the hair follicle.
Kertész, Zs.; Szikszai, Z.; Pelicon, P.; Sim?i?, J.; Telek, A.; Bíró, T.
Differential diagnosis of trichotillomania is often difficult in clinical practice. Trichoscopy (hair and scalp dermoscopy) effectively supports differential diagnosis of various hair and scalp diseases. The aim of this study was to assess the usefulness of trichoscopy in diagnosing trichotillomania. The study included 370 patients (44 with trichotillomania, 314 with alopecia areata and 12 with tinea capitis). Statistical analysis revealed that the main and most characteristic trichoscopic findings of trichotillomania are: irregularly broken hairs (44/44; 100% of patients), v-sign (24/44; 57%), flame hairs (11/44; 25%), hair powder (7/44; 16%) and coiled hairs (17/44; 39%). Flame hairs, v-sign, tulip hairs, and hair powder were newly identified in this study. In conclusion, we describe here specific trichoscopy features, which may be applied in quick, non-invasive, in-office differential diagnosis of trichotillomania. PMID:24096547
Rakowska, Adriana; Slowinska, Monika; Olszewska, Malgorzata; Rudnicka, Lidia
Here we show that cyclophosphamide induces disruption of follicular melanogenesis, which is characterized by abnormal transfer of pigment granules to ectopic hair bulb locations, extrafollicular melanin incontinence, disordered formation of melanosomes, and inhibition of melanosome transfer into precortical keratinocytes. This is in contrast to dexamethasone-induced termination of follicle melanogenesis, which activates premature but predominantly normal catagen development. Cyclophosphamide-induced pigmentation disruption
Andrzej Slominski; Ralf Paus; Przemyslaw Plonka; Bori Handjiski; Marcus Maurer; Ashok Chakraborty; Martin C. Mihm Jr.
In this essay a few relevant aspects of the neural and behavioral development of the brain in the human and in the rat are reviewed and related to the consequences of lesions in the central and peripheral nervous system at early and later age. Movements initially are generated by local circuits in the spinal cord and without the involvement of descending projections. After birth, both in humans and in rats it seems that the devlopment of postural control is the limiting factor for several motor behaviors to mature. Strong indications exist that the cerebellum is significantly involved in this control. Lesions in the CNS at early stages interfere with fundamental processes of neural development, such as the establishment of fiber connections and cell death patterns. Consequently, the functional effects are strongly dependent on the stage of development. The young and undisturbed CNS, on the other hand, has a much greater capacity than the adult nervous system for compensating abnormal reinnervation in the peripheral nervous system. Animal experiments indicated that the cerebellar cortex might play an important part in this compensation. This possibility should be investigated further as it might offer important perspectives for treatment in the human.
Summary Sympathetic nervous system development depends upon many factors that mediate neuron migration, differentiation and survival. Target tissue-derived nerve growth factor (NGF) signaling-induced gene expression is required for survival, differentiation and target tissue innervation of post-migratory sympathetic neurons. However, the transcriptional regulatory mechanisms mediated by NGF signaling are very poorly defined. Here, we identify Egr3, a member of the early growth response (Egr) family of transcriptional regulators, to have an important role in sympathetic nervous system development. Egr3 is regulated by NGF signaling and it is expressed in sympathetic neurons during development when they depend upon NGF for survival and target tissue innervation. Egr3-deficient mice have severe sympathetic target tissue innervation abnormalities and profound physiologic dysautonomia. Unlike NGF which is essential for sympathetic neuron survival and axon branching within target tissues, Egr3 is required for normal terminal axon extension and branching, but not neuron survival. The results indicate that Egr3 is a novel NGF signaling effector which regulates sympathetic neuron gene expression required for normal target tissue innervation and function. Egr3-deficient mice have a phenotype that is remarkably similar to humans with sympathetic nervous system disease, raising the possibility that it may have a role in some forms of human dysautonomia, most of which have no known cause.
Eldredge, Laurie C.; Gao, Xiaoguang M.; Quach, David; Li, Lin; Han, Xiaoqiang; Lomasney, Jon; Tourtellotte, Warren G.
Background Stem/progenitor cells are in the focus of research as a future therapeutic option to stimulate regeneration in diseased renal parenchyma. However, current data indicate that successful seeding of implanted stem/progenitor cells is prevented by harmful interstitial fluid and altered extracellular matrix. To find out possible parameters for cell adaptation, the present investigation was performed. Methods Renal stem/progenitor cells were mounted in an artificial interstitium for perfusion culture. Exposure to chemically defined but CO2-independent culture media was tested during 13 days. Cell biological features were then analyzed by histochemistry, while structural details were investigated by transmission electron microscopy after conventional and improved fixation of specimens. Results Culture of renal stem/progenitor cells as well in Leibovitz’s L-15 Medium as CO2 Independent Medium shows in fluorescence microscopy spatial development of numerous tubules. Specimens of both media fixed by conventional glutaraldehyde exhibit in electron microscopy a homogeneous cell population in developed tubules. In contrast, fixation by glutaraldehyde including tannic acid illuminates that dispersed dark marked cells of unknown function are present. The screening further demonstrates that the dark cell type does not comply with cells found in embryonic, maturing or matured renal parenchyma. Conclusions The actual data show that development of abnormal cell features must be taken into account, when regeneration of renal tubules is simulated under in vitro conditions.
This article reviews the development of hair analysis as a drug-screening technology. It compares the advantages and disadvantages of drug screens that employ urinalysis and hair anal ysis technologies. It reviews the various controversies that have attended the development and implementation of hair analysis. It discusses the role of ideological, sociological, and political factors in the evolution of the technique.
Ethyl glucuronide (EtG) is a minor metabolite of ethanol that can be detected in hair. In some specific situations, head hair can be missing, and therefore, alternative anatomical locations of hair are of interest. In this study, paired hair specimens (head hair and pubic hair) from eight social drinkers were analyzed for EtG. Each sample was decontaminated by two dichloromethane
Pascal Kintz; Marion Villain; Emilie Vallet; Mathieu Etter; Guillaume Salquebre; Vincent Cirimele
Although the development of abnormal myocardial mechanics represents a key step during the transition from hypertension to overt heart failure (HF), the underlying ultrastructural and cellular basis of abnormal myocardial mechanics remains unclear. We therefore investigated how changes in transverse (T)-tubule organization and the resulting altered intracellular Ca(2+) cycling in large cell populations underlie the development of abnormal myocardial mechanics in a model of chronic hypertension. Hearts from spontaneously hypertensive rats (SHRs; n = 72) were studied at different ages and stages of hypertensive heart disease and early HF and were compared with age-matched control (Wistar-Kyoto) rats (n = 34). Echocardiography, including tissue Doppler and speckle-tracking analysis, was performed just before euthanization, after which T-tubule organization and Ca(2+) transients were studied using confocal microscopy. In SHRs, abnormalities in myocardial mechanics occurred early in response to hypertension, before the development of overt systolic dysfunction and HF. Reduced longitudinal, circumferential, and radial strain as well as reduced tissue Doppler early diastolic tissue velocities occurred in concert with T-tubule disorganization and impaired Ca(2+) cycling, all of which preceded the development of cardiac fibrosis. The time to peak of intracellular Ca(2+) transients was slowed due to T-tubule disruption, providing a link between declining cell ultrastructure and abnormal myocardial mechanics. In conclusion, subclinical abnormalities in myocardial mechanics occur early in response to hypertension and coincide with the development of T-tubule disorganization and impaired intracellular Ca(2+) cycling. These changes occur before the development of significant cardiac fibrosis and precede the development of overt cardiac dysfunction and HF. PMID:24186100
Shah, Sanjiv J; Aistrup, Gary L; Gupta, Deepak K; O'Toole, Matthew J; Nahhas, Amanda F; Schuster, Daniel; Chirayil, Nimi; Bassi, Nikhil; Ramakrishna, Satvik; Beussink, Lauren; Misener, Sol; Kane, Bonnie; Wang, David; Randolph, Blake; Ito, Aiko; Wu, Megan; Akintilo, Lisa; Mongkolrattanothai, Thitipong; Reddy, Mahendra; Kumar, Manvinder; Arora, Rishi; Ng, Jason; Wasserstrom, J Andrew
We used knockout mice to show that a cell surface protein called CD34 is required for skin tumor formation in mice. Wild type mice treated with 7-12-Dimethylbenz(a)anthracene (DMBA) and a tumor promoter developed papillomas. When we treated CD34 knockout (KO) mice the same way, n...
Analysis of zebrafish mutants that have defects in motor behavior can allow entrée into the hindbrain and spinal cord networks that control locomotion. Here, we report that zebrafish techno trousers (tnt) locomotor mutants harbor a mutation in slc1a2b, which encodes Eaat2b, a plasma membrane glutamate transporter. We used tnt mutants to explore the effects of impaired glutamate transporter activity on locomotor network function. Wild-type larvae perform robust swimming behavior in response to touch stimuli at two and four days after fertilization. In contrast, tnt mutant larvae demonstrate aberrant, exaggerated body bends beginning two days after fertilization and they are almost paralyzed four days after fertilization. We show that slc1a2b is expressed in glial cells in a dynamic fashion across development, which may explain the abnormal sequence of motor behaviors demonstrated by tnt mutants. We also show that tnt larvae demonstrate enhanced excitation of neurons, consistent with the predicted effects of excessive glutamate. These findings illustrate the dynamic regulation and importance of glutamate transporters during development. Since glutamate toxicity caused by EAAT2 dysfunction is thought to promote several different neurological disorders in humans, including epilepsy and neurodegenerative diseases, tnt mutants hold promise as a new tool to better understand these pathologies.
McKeown, Kelly Anne; Moreno, Rosa; Hall, Victoria L.; Ribera, Angeles B.; Downes, Gerald B.
Tests were conducted on 30 hair dryers for the release of asbestos fibers into the effluent air to evaluate potential consumer exposure, for the Consumer Product Safety Commission. A hair-dryer test system was developed, consisting of a clean air source, a sampling duct assembly, several types of monitoring equipment and filter samplers. Generated samples were assessed by transmission electron microscopy
C. L. Geraci; P. A. Baron; J. W. Carter; D. L. Smith
Tests were conducted on 30 hair dryers for the release of asbestos (1332214) fibers into the effluent air to evaluate potential consumer exposure, for the Consumer Product Safety Commission. A hair dryer test system was developed, consisting of a clean ai...
C. L. Geraci P. A. Baron J. W. Carter D. L. Smith
Telogen effluvium is a common type of hair loss. Although the morphological changes associated with telogen effluvium have been well characterized, the underlying molecular mechanisms remain unknown, and no animal models have been developed. We report here that inducible transgenic mice expressing high levels of the transcription factor, tTA (tetracycline transactivator), plus a reporter luciferase gene, show a reversible hair
Jingshan Chen; Max B. Kelz; Guoqi Zeng; Cathy Steffen; Penny E. Shockett; Gordon Terwilliger; David G. Schatz; Eric J. Nestler
Experiments utilizing the Looptail mutant mouse, which harbors a missense mutation in the vangl2 gene, have been essential for studies of planar polarity and linking the function of the core planar cell polarity proteins to other developmental signals. Originally described as having dominant phenotypic traits, the molecular interactions underlying the Looptail mutant phenotype are unclear because Vangl2 protein levels are significantly reduced or absent from mutant tissues. Here we introduce a vangl2 knockout mouse and directly compare the severity of the knockout and Looptail mutant phenotypes by intercrossing the two lines and assaying the planar polarity of inner ear hair cells. Overall the vangl2 knockout phenotype is milder than the phenotype of compound mutants carrying both the Looptail and vangl2 knockout alleles. In compound mutants a greater number of hair cells are affected and changes in the orientation of individual hair cells are greater when quantified. We further demonstrate in a heterologous cell system that the protein encoded by the Looptail mutation (Vangl2S464N) disrupts delivery of Vangl1 and Vangl2 proteins to the cell surface as a result of oligomer formation between Vangl1 and Vangl2S464N, or Vangl2 and Vangl2S464N, coupled to the intracellular retention of Vangl2S464N. As a result, Vangl1 protein is missing from the apical cell surface of vestibular hair cells in Looptail mutants, but is retained at the apical cell surface of hair cells in vangl2 knockouts. Similarly the distribution of Prickle-like2, a putative Vangl2 interacting protein, is differentially affected in the two mutant lines. In summary, we provide evidence for a direct physical interaction between Vangl1 and Vangl2 through a combination of in vitro and in vivo approaches and propose that this interaction underlies the dominant phenotypic traits associated with the Looptail mutation.
Yin, Haifeng; Copley, Catherine O.; Goodrich, Lisa V.; Deans, Michael R.
The material is presented particularly for practitioners, but academicians should find the material of help and value, also, for introductory courses to study of clinical psychology, abnormal psychology, and psychopathology. Areas covered include the foll...
W. R. Phelps
The present investigation was undertaken to study the effect of dipyridamole on experimental dyskinesia in rats. The movement disorders were produced by intraperitoneal administration of iminodipropionitrile (IDPN) in the dose of 100 mg/kg per day for 12 days. Dipyridamole was administered orally, daily 30 min before IDPN in the doses of 0.5 g/kg, 1 g/kg, and 1.5 g/kg bodyweight in three different groups of rats. Twenty-four hours after the last dose of IDPN, animals were observed for neurobehavioral changes including vertical and horizontal head weaving, circling, backwalking, grip strength, and righting reflex. Immediately after behavioral studies brain specimens were collected for analysis of vitamin E, conjugated dienes, and lipid hydroperoxides as indices of oxygen-derived free radical (OFR) production. Our results showed that concurrent use of dipyridamole significantly protected rats against IDPN-induced neurobehavioral changes in a dose-dependent manner. Treatment of rats with dipyridamole inhibited IDPN-induced decrease of vitamin E and increase in conjugated dienes and lipid hydroperoxides in brain. These findings suggest the involvement of OFR in dipyridamole induced protection against the development of IDPN dyskinesia. Further studies are warranted to determine the role of dipyridamole as a prophylactic agent against the drug induced dyskinetic abnormalities. PMID:7552372
Tariq, M; al-Deeb, S; al-Moutaery, K; Bruyn, G W; Evans, D A; Arshaduddin, M
Iron is essential for organisms. It is mainly utilized in mitochondria for biosynthesis of iron-sulfur clusters, hemes and other cofactors. Mitoferrin 1 and mitoferrin 2, two homologues proteins belonging to the mitochondrial solute carrier family, are required for iron delivery into mitochondria. Mitoferrin 1 is highly expressed in developing erythrocytes which consume a large amount of iron during hemoglobinization. Mitoferrin 2 is ubiquitously expressed, whose functions are less known. Zebrafish with mitoferrin 1 mutation show profound hypochromic anaemia and erythroid maturation arrests, and yeast with defects in MRS3/4, the counterparts of mitoferrin 1/2, has low mitochondrial iron levels and grows poorly by iron depletion. Mitoferrin 1 expression is up-regulated in yeast and mouse models of Fiedreich's ataxia disease and in human cell culture models of Parkinson disease, suggesting its involvement in the pathogenesis of diseases with mitochondrial iron accumulation. In this study we found that reduced mitoferrin levels in C. elegans by RNAi treatment causes pleiotropic phenotypes such as small body size, reduced fecundity, slow movement and increased sensitivity to paraquat. Despite these abnormities, lifespan was increased by 50% to 80% in N2 wild type strain, and in further studies using the RNAi sensitive strain eri-1, more than doubled lifespan was observed. The pathways or mechanisms responsible for the lifespan extension and other phenotypes of mitoferrin RNAi worms are worth further study, which may contribute to our understanding of aging mechanisms and the pathogenesis of iron disorder related diseases.
Ren, Yaguang; Yang, Su; Tan, Guoqiang; Ye, Wei; Liu, Danhui; Qian, Xu; Ding, Zhongying; Zhong, Yuhong; Zhang, Jingrui; Jiang, Dandan; Zhao, Yuhong; Lu, Jianxin
Although hair forms (straight, curly, wavy, etc.) are present in apparently infinite variations, each fibre can be reduced to a finite sequence of tandem segments of just three types: straight, bent/curly, or twisted. Hair forms can thus be regarded as resulting from genetic pathways that induce, reverse or modulate these basic curvature modes. However, physical interconversions between twists and curls demonstrate that strict one-to-one correspondences between them and their genetic causes do not exist. Current hair-curvature theories do not distinguish between bending and twisting mechanisms. We here introduce a multiple papillary centres (MPC) model which is particularly suitable to explain twisting. The model combines previously known features of hair cross-sectional morphology with partially/completely separated dermal papillae within single follicles, and requires such papillae to induce differential growth rates of hair cortical material in their immediate neighbourhoods. The MPC model can further help to explain other, poorly understood, aspects of hair growth and morphology. Separate bending and twisting mechanisms would be preferentially affected at the major or minor ellipsoidal sides of fibres, respectively, and together they exhaust the possibilities for influencing hair-form phenotypes. As such they suggest dialectic for hair-curvature development. We define a natural-dialectic (ND) which could take advantage of speculative aspects of dialectic, but would verify its input data and results by experimental methods. We use this as a top-down approach to first define routes by which hair bending or twisting may be brought about and then review evidence in support of such routes. In particular we consider the wingless (Wnt) and mammalian target of rapamycin (mTOR) pathways as paradigm pathways for molecular hair bending and twisting mechanisms, respectively. In addition to the Wnt canonical pathway, the Wnt/Ca(2+) and planar cell polarity (PCP) pathways, and others, can explain many alternatives and specific variations of hair bending phenotypes. Mechanisms for hair papilla budding or its division by bisection or fission can explain MPC formation. Epithelial-to-mesenchymal (EMT) and mesenchymal-to-epithelial (MET) transitions, acting in collaboration with epithelial-mesenchymal communications are also considered as mechanisms affecting hair growth and its bending and twisting. These may be treated as sub-mechanisms of an overall development from neural-crest stem cell (NCSC) lineages to differentiated hair follicle (HF) cell types, thus providing a unified framework for hair growth and development. PMID:24617997
Nissimov, Joseph N; Das Chaudhuri, Asit Baran
Development and validation of a gas chromatography–negative chemical ionization tandem mass spectrometry method for the determination of ethyl glucuronide in hair and its application to forensic toxicology
Ethyl glucuronide (EtG) is a minor and direct metabolite of ethanol. EtG is incorporated into the growing hair allowing retrospective investigation of chronic alcohol abuse. In this study, we report the development and the validation of a method using gas chromatography–negative chemical ionization tandem mass spectrometry (GC–NCI-MS\\/MS) for the quantification of EtG in hair. EtG was extracted from about 30mg
Hicham Kharbouche; Frank Sporkert; Stéphanie Troxler; Marc Augsburger; Patrice Mangin; Christian Staub
... Treatments should be performed by or under the direct supervision of a dermatologist or other physician who has appropriate training and expertise. In general, three or more treatments are required to achieve permanent hair growth reduction. Darker hair responds best to laser hair ...
Biologists have shown that bat wings contain distributed arrays of flow-sensitive hair receptors. The hair receptors are hypothesized to feedback information on airflows over the bat wing for enhanced stability or maneuverability during flight. Here, we study the geometric specialization of hair-like structures for the detection of changes in boundary layer velocity profiles (shapes). A quasi-steady model that relates the flow velocity profile incident on the longitudinal axis of a hair to the resultant moment and shear force at the hair base is developed. The hair length relative to the boundary layer momentum thickness that maximizes the resultant moment and shear-force sensitivity to changes in boundary layer shape is determined. The sensitivity of the resultant moment and shear force is shown to be highly dependent on hair length. Hairs that linearly taper to a point are shown to provide greater output sensitivity than hairs of uniform cross-section. On an order of magnitude basis, the computed optimal hair lengths are in agreement with the range of hair receptor lengths measured on individual bat species. These results support the hypothesis that bats use hair receptors for detecting changes in boundary layer shape and provide geometric guidelines for artificial hair sensor design and application. PMID:20157224
Dickinson, B T
Glut-2 is a low-affinity transporter present in the plasma membrane of pancreatic beta-cells, hepatocytes and intestine and kidney absorptive epithelial cells of mice. In beta-cells, Glut-2 has been proposed to be active in the control of glucose-stimulated insulin secretion (GSIS; ref. 2), and its expression is strongly reduced in glucose-unresponsive islets from different animal models of diabetes. However, recent investigations have yielded conflicting data on the possible role of Glut-2 in GSIS. Whereas some reports have supported a specific role for Glut-2 (refs 5,6), others have suggested that GSIS could proceed normally even in the presence of low or almost undetectable levels of this transporter. Here we show that homozygous, but not heterozygous, mice deficient in Glut-2 are hyperglycaemic and relatively hypo-insulinaemic and have elevated plasma levels of glucagon, free fatty acids and beta-hydroxybutyrate. In vivo, their glucose tolerance is abnormal. In vitro, beta-cells display loss of control of insulin gene expression by glucose and impaired GSIS with a loss of first phase but preserved second phase of secretion, while the secretory response to non-glucidic nutrients or to D-glyceraldehyde is normal. This is accompanied by alterations in the postnatal development of pancreatic islets, evidenced by an inversion of the alpha- to beta-cell ratio. Glut-2 is thus required to maintain normal glucose homeostasis and normal function and development of the endocrine pancreas. Its absence leads to symptoms characteristic of non-insulin-dependent diabetes mellitus. PMID:9354799
Guillam, M T; Hümmler, E; Schaerer, E; Yeh, J I; Birnbaum, M J; Beermann, F; Schmidt, A; Dériaz, N; Thorens, B; Wu, J Y
An animal model for anticancer drug-induced hair loss has been developed using the Angora rabbit given i.v. doxorubicin, 2 mg\\/kg, twice weekly for 3 weeks. There was a 167% increase in the weight of hair collected by grooming between weeks 2 and 5, and a 72% inhibition of new hair growth at week 6 compared with non-treated animals. The hairs
G. Powis; K. L. Kooistra
The NLRP3 inflammasome complex is responsible for maturation of the pro-inflammatory cytokine, IL-1?. Mutations in NLRP3 are responsible for the cryopyrinopathies, a spectrum of conditions including neonatal-onset multisystem inflammatory disease (NOMID). While excessive production of IL-1? and systemic inflammation are common to all cryopyrinopathy disorders, skeletal abnormalities, prominently in the knees, and low bone mass are unique features of patients with NOMID. To gain insights into the mechanisms underlying skeletal abnormalities in NOMID, we generated knock-in mice globally expressing the D301N NLRP3 mutation (ortholog of D303N in human NLRP3). NOMID mice exhibit neutrophilia in blood and many tissues, including knee joints, and high levels of serum inflammatory mediators. They also exhibit growth retardation and severe postnatal osteopenia stemming at least in part from abnormally accelerated bone resorption, attended by increased osteoclastogenesis. Histologic analysis of knee joints revealed abnormal growth plates, with loss of chondrocytes and growth arrest in the central region of the epiphyses. Most strikingly, a tissue “spike" was observed in the mid-region of the growth plate in the long bones of all NOMID mice that may be the precursor to more severe deformations analogous to those observed in NOMID patients. These findings provide direct evidence linking a NOMID-associated NLRP3-activating mutation to abnormalities of postnatal skeletal growth and bone remodeling.
McGeough, Matthew D.; Pena, Carla; Chen, Debbie; Grimston, Susan K.; Hickman-Brecks, Cynthia L.; Ravindran, Soumya; McAlinden, Audrey; Novack, Deborah V.; Kastner, Daniel L.; Civitelli, Roberto; Hoffman, Hal M.; Mbalaviele, Gabriel
Spontaneous action potentials have been described in developing sensory systems. These rhythmic activities may have instructional roles for the functional development of synaptic connections. The importance of spontaneous action potentials in the developing auditory system is underpinned by the stark correlation between the time of auditory system functional maturity, and the cessation of spontaneous action potentials. A prominent K+ current that regulates patterning of action potentials is IA. This current undergoes marked changes in expression during chicken hair cell development. Although the properties of IA are not normally classified as Ca2+-dependent, we demonstrate that throughout the development of chicken hair cells, IA is greatly reduced by acute alterations of intracellular Ca2+. As determinants of spike timing and firing frequency, intracellular Ca2+ buffers shift the activation and inactivation properties of the current to more positive potentials. Our findings provide evidence to demonstrate that the kinetics and functional expression of IA are tightly regulated by intracellular Ca2+. Such feedback mechanism between the functional expression of IA and intracellular Ca2+ may shape the activity of spontaneous action potentials, thus potentially sculpting synaptic connections in an activity-dependent manner in the developing cochlea.
Levic, Snezana; Lv, Ping; Yamoah, Ebenezer N.
... and develop a reddish hue. To protect your hair from discoloration dermatologists recommend using a leave-in conditioner that contains zinc oxide and wearing a wide-brimmed hat. A hat provides the added benefit of protecting your face and scalp from the ...
Since myelin gene expression is suppressed during active myelination of the undernourished brain, this study was designed to determine the effects of undernourishment on the upregulation of myelin genes and the relationship between upregulation and the 'critical period' associated with permanent hypomyelination of the brain. Long-Evans rat dams were given either ad libitum or restricted access to rat chow to produce two populations of developing offsprings. The food deprivation schedule was designed to produce a degree of growth retardation comparable to our earlier studies of hypomyelination in undernourished brain. The expression of myelin genes, at various developmental ages, was determined in the forebrains from undernourished and normal, well fed controls by Northern analysis. In well nourished forebrain, proteolipid protein (PLP), myelin associated glycoprotein (MAG), and basic protein (BP) messages began to increase polynomially after day 8 post partum, leading to a rapid accumulation of message during the following several days. In undernourished forebrain, PLP, MAG, and BP messages did not show any increase until day 10, and then increased at a diminished rate as compared to well nourished forebrain. Additionally, the two PLP messages (1.6 kb and 3.2 kb) showed different vulnerabilities to protein-calorie undernourishment, which explains the abnormal ratio of the 3.2 and 1.6 kb forms we previously found in undernourished brain. This study shows a pattern of temporal specificity when the myelin PLP, MAG, and BP genes are synchronously upregulated in the normal forebrain to a high rate of transcription between day 7 to 9, which is several days before the onset of rapid myelination of the brain.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7683238
Royland, J E; Konat, G; Wiggins, R C
Ovigerous-hair stripping substance (OHSS) is an active factor in crab hatch water (i.e., filtered medium into which zoea larvae have been released). This factor participates in stripping off the egg attachment structures (i.e., egg case, funiculus, and the coat investing ovigerous hairs) that remain attached to the female's ovigerous hairs after larval release. Thus this activity prepares the hairs for
MASAYUKI SAIGUSA; HIROSHI IWASAKI
Background Children whose mothers consumed alcohol during pregnancy exhibit widespread brain abnormalities and a complex array of behavioral\\u000a disturbances. Here, we used a mouse model of fetal alcohol exposure to investigate relationships between brain abnormalities\\u000a and specific behavioral alterations during adulthood.\\u000a \\u000a \\u000a \\u000a \\u000a Results Mice drank a 10% ethanol solution throughout pregnancy. When fetal alcohol-exposed offspring reached adulthood, we used high\\u000a resolution MRI to
Katherine G Akers; Steven A Kushner; Ana T Leslie; Laura Clarke; Derek van der Kooy; Jason P Lerch; Paul W Frankland
A single hair sample preparation protocol modified from reported method was developed and used to prepare longitudinally sectioned hair for ToF-SIMS analysis. Preliminary results demonstrate that ToF-SIMS is capable of providing molecular distribution of fragment ions from intrinsic constituents as well as external chemicals like the hair dye ingredients used in this study. The observation of pPDA and H 2PO 4- penetrating into the internal region of hair might initiate a renewed interest in exposure study.
Chen, Bo-Jung; Lee, Pei-Ling; Chen, Wen-Yin; Mai, Fu-Der; Ling, Yong-Chien
Loss of cochlear hair cells in mammals is currently believed to be permanent, resulting in hearing impairment that affects more than 10% of the population. Here, we developed two genetic strategies to ablate neonatal mouse cochlear hair cells in vivo. Both Pou4f3(DTR/+) and Atoh1-CreER™; ROSA26(DTA/+) alleles allowed selective and inducible hair cell ablation. After hair cell loss was induced at birth, we observed spontaneous regeneration of hair cells. Fate-mapping experiments demonstrated that neighboring supporting cells acquired a hair cell fate, which increased in a basal to apical gradient, averaging over 120 regenerated hair cells per cochlea. The normally mitotically quiescent supporting cells proliferated after hair cell ablation. Concurrent fate mapping and labeling with mitotic tracers showed that regenerated hair cells were derived by both mitotic regeneration and direct transdifferentiation. Over time, regenerated hair cells followed a similar pattern of maturation to normal hair cell development, including the expression of prestin, a terminal differentiation marker of outer hair cells, although many new hair cells eventually died. Hair cell regeneration did not occur when ablation was induced at one week of age. Our findings demonstrate that the neonatal mouse cochlea is capable of spontaneous hair cell regeneration after damage in vivo. Thus, future studies on the neonatal cochlea might shed light on the competence of supporting cells to regenerate hair cells and on the factors that promote the survival of newly regenerated hair cells. PMID:24496619
Cox, Brandon C; Chai, Renjie; Lenoir, Anne; Liu, Zhiyong; Zhang, LingLi; Nguyen, Duc-Huy; Chalasani, Kavita; Steigelman, Katherine A; Fang, Jie; Rubel, Edwin W; Cheng, Alan G; Zuo, Jian
The outer surface of the hand, limb and body is covered by the epidermis, which is elaborated into a number of specialized appendages, evolved not only to protect and reinforce the skin but also for social signalling. The most prominent of these appendages is the hair follicle. Hair follicles are remarkable because of their prolific growth characteristics and their complexity of differentiation. After initial embryonic morphogenesis, the hair follicle undergoes repeated cycles of regression and regeneration throughout the lifetime of the organism. Studies of mouse mutants with hair loss phenotypes have suggested that the mechanisms controlling the hair cycle probably involve many of the major signalling molecules used elsewhere in development, although the complete pathway of hair follicle growth control is not yet understood. Mouse studies have also led to the discovery of genes underlying several human disorders. Future studies of mouse hair-loss mutants are likely to benefit the understanding of human hair loss as well as increasing our knowledge of mechanisms controlling morphogenesis and tumorigenesis.
Porter, Rebecca M
In order to make greater use of dog hairs as forensic evidence, we have developed a robust method for duplex amplification of adjacent 306 and 332bp amplicons within the 5? hypervariable region (5? HVR) of the canine mitochondrial control region. In support of this, a 595bp region covering 35 polymorphic sites has been sequenced from the blood of 105 UK
Jon H. Wetton; Jenny E. Higgs; Adrian C. Spriggs; Chris A. Roney; Carol S. F. Tsang; Aiden P. Foster
Over the past 40 years, Sandia National Laboratories (SNL) has been actively engaged in research to improve the ability to accurately predict the response of engineered systems to abnormal thermal and structural environments. These engineered systems contain very hazardous materials. Assessing the degree of safety/risk afforded the public and environment by these engineered systems, therefore, is of upmost importance. The ability to accurately predict the response of these systems to accidents (to abnormal environments) is required to assess the degree of safety. Before the effect of the abnormal environment on these systems can be determined, it is necessary to ascertain the nature of the environment. Ascertaining the nature of the environment, in turn, requires the ability to physically characterize and numerically simulate the abnormal environment. Historically, SNL has demonstrated the level of safety provided by these engineered systems by either of two approaches: (1) a purely regulatory approach, or (2) by a Probabilistic Risk Assessment (PRA). This paper will address the latter of the two approaches.
Moya, J.L.; Skocypec, R.D.; Thomas, R.K.
Onset of canonical babbling was investigated for 1,536 high-risk infants at about 10-months corrected age. Although delays were infrequent, they were often associated with genetic, neurological, anatomical, and/or physiological abnormalities. Over half the cases of late canonical babbling, at the time of discovery, were not associated with prior…
Oller, D. Kimbrough; Eilers, Rebecca E.; Neal, A. Rebecca; Cobo-Lewis, Alan B.
The indeterminate gametophyte1 mutation in maize has been known to disrupt development of the female gametophyte. Mutant embryo sacs have abnormal numbers and behavior of micropylar and central cell nuclei, which result in polyembryony and elevated ploidy levels in the endosperm of developing kernels. In this study, we confirm abnormal nuclear behavior and present novel findings. In contrast to the normal form, there is no obvious polarity in two-nucleate embryo sacs or in the micropylar cells of eight-nucleate embryo sacs. We show that the second and third mitoses are not fully synchronized and that additional mitoses can occur in all of the nuclei of the mutant embryo sac or in just the micropylar or central regions. After cellularization, individual micropylar cells can undergo mitosis. Abnormal microtubular behavior results in irregular positioning of the nuclei, asynchronous microtubular patterns in different pairs of nuclei, and abnormal phragmoplasts after the third mitotic division. These results indicate that in addition to acting primarily in controlling nuclear divisions, the indeterminate gametophyte1 gene acts secondarily in regulating microtubule behavior. This cytoskeletal activity most likely controls the polarization and nuclear migration underlying the formation and fate of the cells of the normal embryo sac.
Huang, B. Q.; Sheridan, W. F.
Sebaceous glands (SGs) undergo cyclic renewal independent of hair follicle stem cells (HFSCs) activation while HFSCs have the potential to differentiate into sebaceous gland cells, hair follicle and epidermal keratinocytes. Abnormalities of sebaceous gland progenitor cells contribute to the development of sebaceous neoplasms, but little is known about the role of HFSCs during sebaceous neoplasm development. Here, using dimethylbenzanthracene (DMBA) plus 12-o-tetradecanoyl phorbol-13-acetate (TPA) treatment developing sebaceous neoplasms (SNs) were identified with H&E and Oil red O staining. And then the molecular expression and activation of HFSCs and was characterized by immunostaining. Wnt10b/?-catenin signaling molecular which is important for activation of HFSCs were detected by immunostaining. We found hair follicle and epidermal cell markers were expressed in sebaceous neoplasms. Furthermore, SOX-9 and CD34-positive HFSCs were located in the basal layer of sebaceous lobules within the sebaceous neoplasms. Many appear to be in an active state. Finally, Wnt10b/?-catenin signaling was activated within the basal cells of sebaceous lobules in the sebaceous neoplasms. Collectively, our findings suggest that the abnormal activation of both HFSCs and Wnt10b/?-catenin signaling involves in the development of sebaceous neoplasms.
Qiu, Weiming; Lei, Mingxing; Li, Jin; Wang, Ning; Lian, Xiaohua
An analytical method to detect the illegal application of anabolic steroids in cattle by hair analysis was developed. The time course of incorporation of the orally active xenobiotic steroids ethinyl?oestradiol (EE2) and methyltestosterone (MT) into growing hair, the duration of their detection by hair analysis and the influence of hair pigmentation on steroid concentrations were investigated in detail. Female veal
Andreas Gleixner; Helga Sauerwein; Heinrich H. D. Meyer
DNA isolation from hair shafts can involve a number of steps, each of which adds time to the procedure and increases the risk of contamination. A simple alkaline digestion procedure that directly dissolves hairs was developed and compared with a widely used glass grinding\\/organic extraction method, using samples collected from 30 volunteers with varying population ancestries, hair colors, and hair
Elizabeth A. Graffy; David R. Foran
Premature graying is an important cause of low self-esteem, often interfering with socio-cultural adjustment. The onset and progression of graying or canities correlate very closely with chronological aging, and occur in varying degrees in all individuals eventually, regardless of gender or race. Premature canities may occur alone as an autosomal dominant condition or in association with various autoimmune or premature aging syndromes. It needs to be differentiated from various genetic hypomelanotic hair disorders. Reduction in melanogenically active melanocytes in the hair bulb of gray anagen hair follicles with resultant pigment loss is central to the pathogenesis of graying. Defective melanosomal transfers to cortical keratinocytes and melanin incontinence due to melanocyte degeneration are also believed to contribute to this. The white color of canities is an optical effect; the reflection of incident light masks the intrinsic pale yellow color of hair keratin. Full range of color from normal to white can be seen both along individual hair and from hair to hair, and admixture of pigmented and white hair is believed to give the appearance of gray. Graying of hair is usually progressive and permanent, but there are occasional reports of spontaneous repigmentation of gray hair. Studies evaluating the association of canities with osteopenia and cardiovascular disease have revealed mixed results. Despite the extensive molecular research being carried out to understand the pathogenesis of canities, there is paucity of effective evidence-based treatment options. Reports of repigmentation of previously white hair following certain inflammatory processes and use of drugs have suggested the possibility of cytokine-induced recruitment of outer sheath melanocytes to the hair bulb and rekindled the hope for finding an effective drug for treatment of premature canities. In the end, camouflage techniques using hair colorants are outlined. PMID:23974581
Pandhi, Deepika; Khanna, Deepshikha
The active vitamin D metabolite, 1,25-dihydroxyvitamin D, acting through the vitamin D receptor, regulates the expression of genes in a variety of vitamin D-responsive tissues, including the epidermis. To investigate the role of the vitamin D receptor in mediating epidermal differentiation, we examined the histomorphology and expression of differentiation markers in the epidermis of vitamin D receptor knockout mice generated by gene targeting. The homozygous knockout mouse displayed a phenotype that closely resembles vitamin D-dependent rickets type II in humans, including the development of rickets and alopecia. Hair loss developed by 3 mo after birth and gradually led to nearly total hair loss by 8 mo. Histologic analysis of the skin of homozygous knockout mice revealed dilation of the hair follicles with the formation of dermal cysts starting at the age of 3 wk. These cysts increased in size and number with age. Epidermal differentiation markers, including involucrin, profilaggrin, and loricrin, detected by immunostaining and in situ hybridization, showed decreased expression levels in homozygous knockout mice from birth until 3 wk, preceding the morphologic changes observed in the hair follicles. Keratin 10 levels, however, were not reduced. At the ultrastructural level, homozygous knockout mice showed increased numbers of small dense granules in the granular layer with few or no surrounding keratin bundles and a loss of keratohyalin granules. Thus, both the interfollicular epidermis and the hair follicle appear to require the vitamin D receptor for normal differentiation. The temporal abnormalities between the two processes reflect the apparent lack of requirement for the vitamin D receptor during the anagen phase of the first (developmental) hair cycle, but with earlier effects on the terminal differentiation of the interfollicular epidermis. PMID:11851870
Xie, Zhongjion; Komuves, László; Yu, Qian-Chun; Elalieh, Hashem; Ng, Dean C; Leary, Colin; Chang, Sandra; Crumrine, Debra; Yoshizawa, Tatsuya; Kato, Shigeaki; Bikle, Daniel D
Hair loss is a common problem in captive macaque colonies. A potential factor is the possible influence of stressful environments in the development of hair loss. We examined the relationship between hair loss and chronic hypothalamic-pituitary-adrenal (HPA) axis activity by measuring cortisol in hair. Adult male and female rhesus macaques housed at 3 primate facilities in the United States were screened for degree of hair loss and observed for evidence of hair-plucking behavior. Hair samples and photographic data were obtained from 99 subjects, none of which were hair-pluckers. Macaques with greater than 30% hair loss (alopecia group) showed higher concentrations of hair cortisol than did those with less than 5% hair loss (control group), a finding that was unrelated to age, body weight, or the month in which the sample was collected. Hair loss scores were positively correlated with hair cortisol levels across all monkeys and within the alopecic group alone. In addition, the strong relationship between hair cortisol and alopecia was noted in 2 but not the third facility. Friction with cage surfaces appeared to contribute to hair loss in 18 monkeys. These findings suggest that stress may be one of several factors related to hair loss in some captive nonhuman primates, although whether this relationship is causal or merely correlational is unclear. Moreover, the source of the additional cortisol in the hair of alopecic monkeys (that is, from the circulation or from local synthesis in the skin) remains to be determined. PMID:24827567
Novak, Melinda A; Hamel, Amanda F; Coleman, Kris; Lutz, Corrine K; Worlein, Julie; Menard, Mark; Ryan, Amy; Rosenberg, Kendra; Meyer, Jerrold S
Ten Chesapeake Bay retriever (CBRS) dogs with hair loss were recruited in collaboration with the American Chesapeake Club. All dogs had nonpruritic, noninflammatory, regionalized hair loss affecting the same areas of the body in male and female dogs. Hormonal investigations showed increased adrenal and sex steroid concentration in seven cases. Histopathology revealed follicular hyperkeratosis and plugging, follicular atrophy, and occasional melanin clumping with malformed hair shafts. This study suggests that hair loss in CBRS is a breed syndrome in which young adult dogs have hair loss characterized by unusual histological features and abnormal steroid production. A familial predisposition seems likely and selective breeding might reduce the occurrence of this condition. PMID:15725104
Cerundolo, R; Mauldin, E A; Goldschmidt, M H; Beyerlein, S L; Refsal, K R; Oliver, J W
Female pattern hair loss (FPHL) is the most common hair loss disorder in women. Initial signs may develop during teenage years leading to a progressive hair loss with a characteristic pattern distribution. The condition is characterized by progressive replacement of terminal hair follicles over the frontal and vertex regions by miniaturized follicles, that leads progressively to a visible reduction in hair density. Women diagnosed with FPHL may undergo significant impairment of quality of life. FPHL diagnosis is mostly clinical. Depending on patient history and clinical evaluation, further diagnostic testing may be useful. The purpose of the paper is to review the current knowledge about epidemiology, pathogenesis, clinical manifestations, and diagnosis of FPHL.
Vujovic, Anja; Del Marmol, Veronique
Although the biochemical composition of hair is similar among racial and ethnic groups, the hair structure between them varies, and individuals with curly hair pose specific challenges and special considerations when a surgical option for alopecia is considered. Hair restoration in this population should therefore be approached with knowledge on the clinical characteristics of curly hair, hair grooming techniques that may influence the management, unique indications for the procedure, surgical instrumentation used, and the complications that may arise. PMID:24680003
Rogers, Nicole E; Callender, Valerie D
Homozygous mice overexpressing Claudin-6 (Cldn6) exhibit a perturbation in the epidermal differentiation program leading to a defective epidermal permeability barrier (EPB) and dehydration induced death ensuing within 48 h of birth [Turksen, K., Troy, T.C., 2002. Permeability barrier dysfunction in transgenic mice overexpressing claudin 6. Development 129, 1775-1784]. Their heterozygous counterparts are also born with an incomplete EPB; however, barrier formation continues after birth and normal hydration levels are achieved by postnatal day 12 allowing survival into adulthood. Heterozygous Inv-Cldn6 mice exhibit a distinct coat phenotype and histological analysis shows mild epidermal hyperkeratosis. Expression of K5 and K14 is aberrant, extending beyond the basal layer into the suprabasal layer where they are not co-localized suggesting that their expression is uncoupled. There is also atypical K17 and patchy K15 expression in the basal layer with no K6 expression in the interfollicular epidermis; together with marked changes in late differentiation markers (e.g. profilaggrin/filaggrin, loricrin, transglutaminase 3) indicating that the normal epidermal differentiation program is modified. The expression compartment of various Cldns is also perturbed although overall protein levels remained comparable. Most notably induction of Cldn5 and Cldn8 was observed in the Inv-Cldn6 epidermis. Heterozygous Inv-Cldn6 animals also exhibit subtle alterations in the differentiation program of the hair follicle including a shorter anagen phase, and altered hair type distribution and length compared to the wild type; the approximately 20% increase in zig-zag hair fibers at the expense of guard hairs and the approximately 30% shorter guard hairs contribute to coat abnormalities in the heterozygous mice. In addition, the transgenic hair follicles exhibit a decreased expression of K15 as well as some hair-specific keratins and express Cldn5 and Cldn18, which are not detectable in the wild type. These data indicate that Cldn6 plays a role in the differentiation processes of the epidermis and hair follicle and supports the notion of a link between Cldn regulation and EPB assembly/maintenance as well as the hair cycle. PMID:15908185
Troy, Tammy-Claire; Rahbar, Ramtin; Arabzadeh, Azadeh; Cheung, Robert Man-Kit; Turksen, Kursad
In 1956 Klingmüller first described the trichorhinophalangeal syndrome (TRPS), which was named by Giedion ten years later. The syndrome includes a combination of typical hair, facial and bone abnormalities with variable expression allowing the further distinction of three subtypes. In a 37-year old patient with TRPS type I who reportedly had reduced hair growth length, clinically fine and brittle hair were found. Scanning electron microscopy revealed widely spaced cuticular scales. Quantitative measurement of the biomechanical properties of the hair showed a significant increase in the viscous parameter. This could be a result of decreased disulfide bridges and increased halogen bonds in the keratin matrix of the hair. In dermatological practice patients with TRPS often present because of hair abnormalities. Because of premature arthrosis due to skeletal abnormalities, occupational counseling is advised.Congenital heart problems, kidney abnormalities and endocrinological problems are rare, but should be sought in the symptomatic individual. Apart from mild hair care and avoidance of additional physical or chemical injuries due to hair cosmetic procedures,there is no treatment for the hair defects. PMID:11220240
Schacht, V; Borelli, S; Tsambaos, D; Spycher, M A; Trüeb, R M
The spindle assembly checkpoint (SAC) ensures correct chromosome segregation during mitosis by preventing aneuploidy, an event that is detrimental to the fitness and survival of normal cells but oncogenic in tumor cells. Deletion of SAC genes is incompatible with early mouse development, and RNAi-mediated depletion of SAC components in cultured cells results in rapid death. Here we describe the use of a conditional KO of mouse Mad2, an essential component of the SAC signaling cascade, as a means to selectively induce chromosome instability and aneuploidy in the epidermis of the skin. We observe that SAC inactivation is tolerated by interfollicular epidermal cells but results in depletion of hair follicle bulge stem cells. Eventually, a histologically normal epidermis develops within ?1 mo after birth, albeit without any hair. Mad2-deficient cells in this epidermis exhibited abnormal transcription of metabolic genes, consistent with aneuploid cell state. Hair follicle bulge stem cells were completely absent, despite the continued presence of rudimentary hair follicles. These data demonstrate that different cell lineages within a single tissue respond differently to chromosome instability: some proliferating cell lineages can survive, but stem cells are highly sensitive.
Foijer, Floris; DiTommaso, Tia; Donati, Giacomo; Hautaviita, Katta; Xie, Stephanie Z.; Heath, Emma; Smyth, Ian; Watt, Fiona M.; Sorger, Peter K.; Bradley, Allan
A Pakistani kindred comprising 5 generations contained 9 males and 4 females with alopecia universalis as a single abnormality without any associated defects. The skin biopsy from the scalp showed hair follicles without hair. Analysis of the pedigree is strongly suggestive of autosomal recessive inheritance, and consanguineous loops could account for all affected persons being homozygous for the abnormal allele. PMID:8357006
Ahmad, M; Abbas, H; Haque, S
There is a growing body of evidences that acquired chromosomal abnormalities in bone marrow (BM) cells are associated with clinical manifestations of myelodysplastic syndrome (MDS). However, to our knowledge, there are no reports that describe the association between chromosomal abnormalities in MDS and graft-versus-host disease (GVHD) after allogeneic stem cell transplantation (allo-SCT). Here, we describe two MDS cases with trisomy 8 and der(1;7)(q10;p10), who developed severe GVHD after allo-SCT. We analyzed cytokine production and cell survival of monocytes from these patients with MDS before allo-SCT, in comparison with healthy controls or an MDS patient with a different chromosomal abnormality, who has not developed GVHD. The monocytes from MDS patients with trisomy 8 and der(1;7)(q10;p10) produced a larger amount of pro-inflammatory cytokine, tumor necrosis factor-?, and a smaller amount of anti-inflammatory cytokine, interleukin-10, on stimulation with Toll-like receptor (TLR) ligands. In addition, the monocytes from MDS cases with GVHD showed a decrease in apoptotic cell death upon stimulation with TLR ligands. We also detected host-derived pro-inflammatory antigen-presenting cells (APCs) in skin GVHD lesions after allo-SCT. These data suggest that trisomy 8 and der(1;7)(q10;p10) may be associated with the development of severe GVHD, by prolonging survival of pro-inflammatory host-derived APCs in GVHD lesions. PMID:23470132
Arai, Yasuyuki; Yamashita, Kouhei; Mizugishi, Kiyomi; Takaori-Kondo, Akifumi; Chiba, Tsutomu; Watanabe, Tomohiro
Several nitriles have been demonstrated to cause hair cell loss in the inner ear of the rat, but the susceptibility of other species to this toxic effect has not been investigated. Adult male Swiss mice were administered (po) control vehicle, cis-crotononitrile (2.75 mmol/kg), or 3,3'-iminodipropionitrile (IDPN, at 8, 16, and 24 mmol/kg), and the changes in vestibular function were assessed by behavioral endpoints. In addition, surface preparations of the vestibular sensory epithelia were examined for hair cell loss using scanning electron microscopy (SEM). IDPN, in a dose-dependent manner, and cis-crotononitrile induced both vestibular dysfunction and loss of hair bundles. Male Dunkin Hartley guinea pigs were administered IDPN (0, 1.6, 2.4, or 3.2 mmol/kg, ip), and their vestibular and auditory sensory epithelia were examined by SEM. The guinea pigs developed behavioral abnormalities indicative of vestibular dysfunction, with more overt effects observed in the animals treated with larger doses, and displayed a dose-dependent loss of hair bundles in both the vestibular and the auditory epithelia. Frogs (Rana perezi) were administered IDPN (0, 16, 24, or 32 mmol/kg, ip), and their sensory epithelia in the inner ear were examined by SEM. IDPN caused behavioral abnormalities indicative of vestibular dysfunction and loss of hair bundles. We conclude that some nitriles are thorough ototoxic compounds affecting hair cells in a wide range of species. This conclusion highlights the potential interest of this toxic effect and offers new animal models in which to decipher its basis. PMID:17159233
Soler-Martín, Carla; Díez-Padrisa, Núria; Boadas-Vaello, Pere; Llorens, Jordi
The pathogenesis of lower urinary tract obstruction is disputed, particularly its relation to both abnormal prostatic development and the prune belly syndrome (PBS). In an attempt to clarify this issue we examined 11 males (17-38 weeks gestation) with PBS who were autopsied at our institution. The lower urinary tract was embedded intact and prepared as serial histologic sections. Of the 11 cases, 8 demonstrated mechanical obstruction of the lower urinary tract. In five of these eight cases, a "flap-valve" structure was formed by an abnormal angulation between the prostatic and penile portions of the urethra. These had dilated, thin-walled bladders and prostates and moderate to severe renal dysplasia. One of the eight cases had a valve-like obstruction at the level of the mid-prostatic urethra associated with a complex cloacal malformation and a thin-walled bladder, another case had an epithelial plug at the penile meatus, and the last of the eight cases had a posterior urethral valve. The three remaining cases showed no mechanical obstruction. However, each had megacystis with marked thickening, interstitial fibrosis, and disarray of smooth muscle bundles in the bladder wall. In 10 cases, the prostate had no or only sparse, flattened glands. These results suggest that the abnormal development of the prostate in PBS may be explained as a pressure-induced dysplasia rather than a primary maldevelopment. The findings further suggest that abnormal prostatic development and the prune belly syndrome may arise from either anatomic obstruction of various types or functional obstruction from megacystis. PMID:11779049
Volmar, K E; Fritsch, M K; Perlman, E J; Hutchins, G M
Kit\\u000a \\u000a W-2Bao\\u000a mice are single-gene autosomal dominant mutation mice with a B6 background that were bred in our laboratory. Heterozygotes\\u000a had morphological characteristics including albinism of the abdomen, extremities, and tail, whereas the homozygotes had albinism\\u000a of the body, black eyes, and infertility. The homozygous mutants showed small, structurally abnormal gonads, and lacked germ\\u000a cells. Heterozygous male mice lacked germ
BaoJin Wu; LiJing Yin; ZhengLan Lu; YuShu Yin; WeiWei Yang; Rong Yang; XiaoDong Kang; GuiJie Liu; HongPing Yin; LiPing Yu; MeiEr Gu; PeiLin Wu
In all eukaryotic cells, the endoplasmic reticulum (ER) forms a tubular network whose generation requires the fusion of ER membranes. In Arabidopsis (Arabidopsis thaliana), the membrane-bound GTPase ROOT HAIR DEFECTIVE3 (RHD3) is a potential candidate to mediate ER fusion. In addition, Arabidopsis has two tissue-specific isoforms of RHD3, namely RHD3-like (RL) proteins, and their function is not clear. Here, we show that a null allele of RHD3, rhd3-8, causes growth defects and shortened root hairs. A point mutant, rhd3-1, exhibits a more severe growth phenotype than the null mutant, likely because it exerts a dominant-negative effect on the RL proteins. Genetic analysis reveals that the double deletion of RHD3 and RL1 is lethal and that the rhd3 rl2 plants produce no viable pollen, suggesting that the RL proteins are redundant to RHD3. RHD3 family proteins can replace Sey1p, the homolog of RHD3 in yeast (Saccharomyces cerevisiae), in the maintenance of ER morphology, and they are able to fuse membranes both in vivo and in vitro. Our results suggest that RHD3 proteins mediate ER fusion and are essential for plant development and that the formation of the tubular ER network is of general physiological significance. PMID:23922269
Zhang, Miao; Wu, Fuyun; Shi, Juanming; Zhu, Yimeng; Zhu, Zhengmao; Gong, Qingqiu; Hu, Junjie
The 14-3-3? (Stratifin; Sfn) is a cell cycle regulator intimately involved in the program of epithelial keratinization. 14-3-3? is unique in that it is expressed primarily in epithelial cells and is frequently silenced in epithelial cancers. Despite its well-documented role as a cell cycle regulator and as a tumor suppressor, the function of 14-3-3? in the intricate balance of proliferation and differentiation in epithelial development is poorly understood. A mutation in 14-3-3? was found to be responsible for the repeated epilation (Er) phenotype. It has previously been shown that Sfn(+/Er) mice are characterized by repeated hair loss and regrowth, whereas Sfn(Er/Er) mice die at birth displaying severe oral fusions and limb abnormalities as a result of defects in keratinizing epithelia. Here we show that mice heterozygous for the 14-3-3? mutation have severe defects in hair shaft differentiation, resulting in destruction of the hair shaft during morphogenesis. Furthermore, we report that the interfollicular epidermis and sebaceous glands are hyperproliferative, coincident with expanded nuclear Yap1 (Yes-associated protein 1)--a critical modulator of epidermal stem cell proliferation. We also report that hair follicle stem cells in the bulge cycle abnormally, raising important questions as to the role of 14-3-3? in the bulge. PMID:22377760
Hammond, Nigel L; Headon, Denis J; Dixon, Michael J
This review presents a systematic approach to the diagnosis of hair loss. An accurate diagnosis is based on history, clinical examination, laboratory tests, and scalp biopsy. Whether the hair loss is a cicatricial or noncicatricial alopecia guides one's history taking. After assessing the patient's global appearance, the hair and scalp are evaluated, aided by a hair pull, hair tug, Hair Card, and hair mount. Scalp biopsies can confirm a diagnosis and are essential in all cases of cicatricial alopecia. In all patients with hair loss a complete blood count, ferritin, thyroid stimulating hormone, and vitamin D 25OH should be ordered. PMID:23159173
Jackson, Adrianna J; Price, Vera H
Summary Background Abnormal test results do not always receive timely follow-up, even when providers are notified through electronic health record (EHR)-based alerts. High workload, alert fatigue, and other demands on attention disrupt a provider’s prospective memory for tasks required to initiate follow-up. Thus, EHR-based tracking and reminding functionalities are needed to improve follow-up. Objectives The purpose of this study was to develop a decision-support software prototype enabling individual and system-wide tracking of abnormal test result alerts lacking follow-up, and to conduct formative evaluations, including usability testing. Methods We developed a working prototype software system, the Alert Watch And Response Engine (AWARE), to detect abnormal test result alerts lacking documented follow-up, and to present context-specific reminders to providers. Development and testing took place within the VA’s EHR and focused on four cancer-related abnormal test results. Design concepts emphasized mitigating the effects of high workload and alert fatigue while being minimally intrusive. We conducted a multifaceted formative evaluation of the software, addressing fit within the larger socio-technical system. Evaluations included usability testing with the prototype and interview questions about organizational and workflow factors. Participants included 23 physicians, 9 clinical information technology specialists, and 8 quality/safety managers. Results Evaluation results indicated that our software prototype fit within the technical environment and clinical workflow, and physicians were able to use it successfully. Quality/safety managers reported that the tool would be useful in future quality assurance activities to detect patients who lack documented follow-up. Additionally, we successfully installed the software on the local facility’s “test” EHR system, thus demonstrating technical compatibility. Conclusion To address the factors involved in missed test results, we developed a software prototype to account for technical, usability, organizational, and workflow needs. Our evaluation has shown the feasibility of the prototype as a means of facilitating better follow-up for cancer-related abnormal test results.
Smith, M.; Murphy, D.; Laxmisan, A.; Sittig, D.; Reis, B.; Esquivel, A.; Singh, H.
Long hairs of fur pelts known as guard hairs are removed to reveal soft underfur by contacting the pelt with a substrate coated with adhesive and then pulling the substrate away from the pelt. Recoverable or nonrecoverable adhesive systems may be used.
H. E. Hull
The workshop on Hair Follicle Stem Cells brought together investigators who have used a variety of approaches to try to understand the biology of follicular epithelial stem cells, and the role that these cells play in regulating the hair cycle. One of the main concepts to emerge from this workshop is that follicular epithelial stem cells are multipotent, capable of
Robert M. Lavker; Tung-Tien Sun; Hideo Oshima; Yann Barrandon; Masashi Akiyama; Corinne Ferraris; Genevieve Chevalier; Bertrand Favier; Colin A. B. Jahoda; Danielle Dhouailly; Andrei A. Panteleyev; Angela M. Christiano
The increasing use of the hair follicle as a stem cell paradigm is due in part to the complex interplay between epithelial, dermal and other cell types, each with interesting differentiation potential and prospective therapeutic applications. This review focuses on research into the environmental niche, gene expression profiles and plasticity of hair follicle stem cell populations, where many recent advances
James M. Waters; Gavin D. Richardson; Colin A. B. Jahoda
The present invention relates to a long hair shampoo basin for use at barber shops and beauty salons. More specifically, the present invention is directed to shampoo basins which are adapted for shampooing longer hair than is accommodated by present basin...
... the jurisdiction of FDA's Office of Cosmetics and Colors in the Center for Food Safety and Applied Nutrition. The practice of professional hair ... popular belief, shaving does not change the texture, color, or growth rate of hair. ... Safety Commission. back to top This article appears on ...
Sound detection by inner ear hair cells requires tip links that interconnect mechanosensory stereocilia and convey force to yet unidentified transduction channels. Current models postulate a static composition of the tip link, with protocadherin 15 (PCDH15) at the lower and cadherin 23 (CDH23) at the upper end of the link. In terminally differentiated mammalian auditory hair cells, tip links are subjected to sound-induced forces throughout an organism's life. Although hair cells can regenerate disrupted tip links and restore hearing, the molecular details of this process are unknown. We developed a novel implementation of backscatter electron scanning microscopy to visualize simultaneously immuno-gold particles and stereocilia links, both of only a few nanometers in diameter. We show that functional, mechanotransduction-mediating tip links have at least two molecular compositions, containing either PCDH15/CDH23 or PCDH15/PCDH15. During regeneration, shorter tip links containing nearly equal amounts of PCDH15 at both ends appear first. Whole-cell patch-clamp recordings demonstrate that these transient PCDH15/PCDH15 links mediate mechanotransduction currents of normal amplitude but abnormal Ca(2+)-dependent decay (adaptation). The mature PCDH15/CDH23 tip link composition is re-established later, concomitant with complete recovery of adaptation. Thus, our findings provide a molecular mechanism for regeneration and maintenance of mechanosensory function in postmitotic auditory hair cells and could help identify elusive components of the mechanotransduction machinery. PMID:23776407
Indzhykulian, Artur A; Stepanyan, Ruben; Nelina, Anastasiia; Spinelli, Kateri J; Ahmed, Zubair M; Belyantseva, Inna A; Friedman, Thomas B; Barr-Gillespie, Peter G; Frolenkov, Gregory I
Sound detection by inner ear hair cells requires tip links that interconnect mechanosensory stereocilia and convey force to yet unidentified transduction channels. Current models postulate a static composition of the tip link, with protocadherin 15 (PCDH15) at the lower and cadherin 23 (CDH23) at the upper end of the link. In terminally differentiated mammalian auditory hair cells, tip links are subjected to sound-induced forces throughout an organism's life. Although hair cells can regenerate disrupted tip links and restore hearing, the molecular details of this process are unknown. We developed a novel implementation of backscatter electron scanning microscopy to visualize simultaneously immuno-gold particles and stereocilia links, both of only a few nanometers in diameter. We show that functional, mechanotransduction-mediating tip links have at least two molecular compositions, containing either PCDH15/CDH23 or PCDH15/PCDH15. During regeneration, shorter tip links containing nearly equal amounts of PCDH15 at both ends appear first. Whole-cell patch-clamp recordings demonstrate that these transient PCDH15/PCDH15 links mediate mechanotransduction currents of normal amplitude but abnormal Ca2+-dependent decay (adaptation). The mature PCDH15/CDH23 tip link composition is re-established later, concomitant with complete recovery of adaptation. Thus, our findings provide a molecular mechanism for regeneration and maintenance of mechanosensory function in postmitotic auditory hair cells and could help identify elusive components of the mechanotransduction machinery.
Indzhykulian, Artur A.; Stepanyan, Ruben; Nelina, Anastasiia; Spinelli, Kateri J.; Ahmed, Zubair M.; Belyantseva, Inna A.; Friedman, Thomas B.; Barr-Gillespie, Peter G.; Frolenkov, Gregory I.
Uneven structures on hair fiber surface, such as lift up of cuticle or build up of hair spray ingredients, generally cause a diffuse reflection which results in a dull and unhealthy appearance. However, in the case of finer structure than wavelength of visible light, the optical properties change significantly. An application of the phenomenon to hair care products is reported in this paper. Formation of the fine structure on hair surface was achieved by only a shampoo and rinse-off conditioner system including amino-silicone. Chroma enhancement of hair and light introduction into hair fibers were observed simultaneously with formation of the fine structure on the hair surface. The light introduction phenomenon is understood in terms of "Effective Medium Approximation" (EMA). The simulation study based on EMA indicates that a very low refractive index surface is expected to be realized, which well explains the optical experimental results. When the shampoo and conditioner system developed to form the structure on fiber surface was applied to dyed hair, enhancement and long-lasting of vivid appearance was confirmed in spite of dye elution. PMID:17728928
Watanabe, Shunsuke; Sato, Hirayuki; Shibuichi, Satoshi; Okamoto, Masayuki; Inoue, Shigeto; Satoh, Naoki
Background Aneuploidy is one of the major factors that result in low efficiency in human infertility treatment by in vitro fertilization (IVF). The development of DNA microarray technology allows for aneuploidy screening by analyzing all 23 pairs of chromosomes in human embryos. All chromosome screening for aneuploidy is more accurate than partial chromosome screening, as errors can occur in any chromosome. Currently, chromosome screening for aneuploidy is performed in developing embryos, mainly blastocysts. It has not been performed in arrested embryos and/or compared between developing embryos and arrested embryos from the same IVF cycle. Methods The present study was designed to examine all chromosomes in blastocysts and arrested embryos from the same cycle in patients of advanced maternal ages. Embryos were produced by routine IVF procedures. A total of 90 embryos (45 blastocysts and 45 arrested embryos) from 17 patients were biopsied and analyzed by the Agilent DNA array platform. Results It was found that 50% of the embryos developed to blastocyst stage; however, only 15.6% of the embryos (both blastocyst and arrested) were euploid, and most (84.4%) of the embryos had chromosomal abnormalities. Further analysis indicated that 28.9% of blastocysts were euploid and 71.1% were aneuploid. By contrast, only one (2.2%) arrested embryo was euploid while others (97.8%) were aneuploid. The prevalence of multiple chromosomal abnormalities in the aneuploid embryos was also higher in the arrested embryos than in the blastocysts. Conclusions These results indicate that high proportions of human embryos from patients of advanced maternal age are aneuploid, and the arrested embryos are more likely to have abnormal chromosomes than developing embryos.
Chemotherapy-induced alopecia is a major problem in clinical oncology. Doxorubicin, a widely used cancer chemotherapy drug, induces disruption of the hair cycle and subsequent alopecia. We show in this report that doxorubicin causes disruption of the hair-follicle-associated blood vessel network resulting in a greatly reduced density of these blood vessels. Dystrophic hair follicles were also observed with abnormal melanogenesis in
Yasuyuki Amoh; Lingna Li; Kensei Katsuoka; Robert M. Hoffman
Many human diseases share a developmental origin that manifests during childhood or maturity. Aneuploid syndromes are caused by supernumerary or reduced number of chromosomes and represent an extreme example of developmental disease, as they have devastating consequences before and after birth. Investigating how alterations in gene dosage drive these conditions is relevant because it might help treat some clinical aspects. It may also provide explanations as to how quantitative differences in gene expression determine phenotypic diversity and disease susceptibility among natural populations. Here, we aimed to produce induced pluripotent stem cell (iPSC) lines that can be used to improve our understanding of aneuploid syndromes. We have generated iPSCs from monosomy X [Turner syndrome (TS)], trisomy 8 (Warkany syndrome 2), trisomy 13 (Patau syndrome) and partial trisomy 11;22 (Emanuel syndrome), using either skin fibroblasts from affected individuals or amniocytes from antenatal diagnostic tests. These cell lines stably maintain the karyotype of the donors and behave like embryonic stem cells in all tested assays. TS iPSCs were used for further studies including global gene expression analysis and tissue-specific directed differentiation. Multiple clones displayed lower levels of the pseudoautosomal genes ASMTL and PPP2R3B than the controls. Moreover, they could be transformed into neural-like, hepatocyte-like and heart-like cells, but displayed insufficient up-regulation of the pseudoautosomal placental gene CSF2RA during embryoid body formation. These data support that abnormal organogenesis and early lethality in TS are not caused by a tissue-specific differentiation blockade, but rather involves other abnormalities including impaired placentation. PMID:21949351
Li, Wen; Wang, Xianming; Fan, Wenxia; Zhao, Ping; Chan, Yau-Chi; Chen, Shen; Zhang, Shiqiang; Guo, Xiangpeng; Zhang, Ya; Li, Yanhua; Cai, Jinglei; Qin, Dajiang; Li, Xingyan; Yang, Jiayin; Peng, Tianran; Zychlinski, Daniela; Hoffmann, Dirk; Zhang, Ruosi; Deng, Kang; Ng, Kwong-Man; Menten, Bjorn; Zhong, Mei; Wu, Jiayan; Li, Zhiyuan; Chen, Yonglong; Schambach, Axel; Tse, Hung-Fat; Pei, Duanqing; Esteban, Miguel A
Loss of hair and hair colour is associated with ageing, and when it involves the scalp hair, it can be distressing to both sexes. Hair loss resulting from cancer chemotherapy is particularly distressing. However, safe, effective therapies directed to hair have only just started to be developed. The hair follicle is a complex skin appendage composed of epidermal and dermal tissue, with specialized keratinocytes, the hair matrix cells, forming the hair shaft. Specific therapy of the hair follicle depends on selective targeting of specific cells of the hair follicle. We have developed the histoculture of intact hair-growing skin on sponge-gel matrices. We have recently found in histocultured skin that liposomes can selectively target hair follicles to deliver both small and large molecules. That liposomes can target the hair follicle for delivery has been confirmed independently. Two decades ago we introduced the technique of entrapping DNA in liposomes for use in gene therapy. In this report we describe the selective targeting of the lacZ reporter gene to the hair follicles in mice after topical application of the gene entrapped in liposomes. These results demonstrate that highly selective, safe gene therapy for the hair process is feasible. PMID:7585157
Li, L; Hoffman, R M
Cosmetic hair treatments have been referred to as 'the pitfall' of hair analysis. However, most cosmetic treatments, when applied to the hair as instructed by the product vendors, do not interfere with analysis, provided such treatments can be identified by the laboratory and the samples analyzed and reported appropriately for the condition of the hair. This paper provides methods for identifying damaged or porous hair samples using digestion rates of hair in dithiothreitol with and without proteinase K, as well as a protein measurement method applied to dithiothreitol-digested samples. Extremely damaged samples may be unsuitable for analysis. Aggressive and extended aqueous washing of hair samples is a proven method for removing or identifying externally derived drug contamination of hair. In addition to this wash procedure, we have developed an alternative wash procedure using 90% ethanol for washing damaged or porous hair. The procedure, like the aqueous wash procedure, requires analysis of the last of five washes to evaluate the effectiveness of the washing procedure. This evaluation, termed the Wash Criterion, is derived from studies of the kinetics of washing of hair samples that have been experimentally contaminated and of hair from drug users. To study decontamination methods, in vitro contaminated drug-negative hair samples were washed by both the aqueous buffer method and a 90% ethanol method. Analysis of cocaine and methamphetamine was by liquid chromatography-tandem mass spectrometry (LC/MS/MS). Porous hair samples from drug users, when washed in 90% ethanol, pass the wash criterion although they may fail the aqueous wash criterion. Those samples that fail both the ethanolic and aqueous wash criterion are not reported as positive for ingestion. Similar ratios of the metabolite amphetamine relative to methamphetamine in the last wash and the hair is an additional criterion for assessing contamination vs. ingestion of methamphetamine. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24817048
Hill, Virginia; Loni, Elvan; Cairns, Thomas; Sommer, Jonathan; Schaffer, Michael
Hair cells in the mammalian inner ear convert sound into electrical signals that are relayed to the nervous system by the chemical neurotransmitter glutamate. Electrical information encoding sound is then passed through the central nervous system to the higher auditory centres in the brain, where it is used to construct a temporally and spatially accurate representation of the auditory landscape. To achieve this, hair cells must encode fundamental properties of sound stimuli at extremely high rates, not only during mechano-electrical transduction, which occurs in the hair bundles at the cell apex, but also during electrochemical transduction at the specialized ribbon synapses at the cell base. How is the development of such a sophisticated cell regulated? More specifically, to what extent does physiological activity contribute to the progression of the intrinsic genetic programmes that drive cell differentiation? Hair cell differentiation takes about 3 weeks in most rodents, from terminal mitosis during embryonic development to the onset of hearing around 2 weeks after birth. Until recent years, most of the molecules involved in hair cell development and function were unknown, which was mainly due to difficulties in working with the mammalian cochlea and the very small number of hair cells, about 16,000 in humans, present in the auditory organ. Recent advances in the ability to record from the acutely isolated cochlea maintained in near-physiological conditions, combined with the use of genetically modified mouse models, has allowed the identification of several proteins and molecular mechanisms that are crucial for the maturation and function of hair cells. In this article, I highlight recent findings from my laboratory that have furthered our understanding of how developing hair cells acquire the remarkable sensitivity of adult auditory sensory receptors.
It is well established that 14-3-3 proteins are key regulators of multiple stress signal transduction cascades. However, the biological functions of soybean 14-3-3 proteins, especially in plant drought response, are not yet known. In this study, we characterized a Glycine soja 14-3-3 gene, GsGF14o, which is involved in plant development and drought response. GsGF14o expression was greatly induced by drought stress, as evidenced by the quantitative real-time PCR and ?-glucuronidase (GUS) activity analysis. GsGF14o overexpression in Arabidopsis thaliana resulted in decreased drought tolerance during seed germination and seedling growth. Furthermore, silencing of AtGF14µ, the most homologous 14-3-3 gene of GsGF14o, led to enhanced drought tolerance at both the seed germination and seedling stage. Unexpectedly, GsGF14o transgenic lines showed reduced water loss and transpiration rates compared with wild-type plants, which was demonstrated to be the consequence of the decreased stomatal size. At the same time, the smaller stomata due to GsGF14o overexpression led to a relatively slow net photosynthesis rate, which led to a growth penalty under drought stress. We further demonstrated that GsGF14o overexpression caused deficits in root hair formation and development, and thereby reduced the water intake capacity of the transgenic root system. In addition, GsGF14o overexpression down-regulated the transcript levels of drought-responsive marker genes. Finally, we also investigated the tissue-specific accumulation of GsGF14o by using a GUS activity assay. Collectively, the results presented here confirm that GsGF14o plays a dual role in drought stress responses through its involvement in the regulation of stomatal size and root hair development. PMID:24272249
Sun, Xiaoli; Luo, Xiao; Sun, Mingzhe; Chen, Chao; Ding, Xiaodong; Wang, Xuedong; Yang, Shanshan; Yu, Qingyue; Jia, Bowei; Ji, Wei; Cai, Hua; Zhu, Yanming
Oculo-dento-digital dysplasia (ODDD) is a rare autosomal dominant congenital disorder mainly affecting the development of the face, eyes, skeletal system, heart and dentition. ODDD has been mapped to chromosome 6q22-q24 and germline mutations have been identified in the connexin 43 gene, GJA1. Abnormalities of the skin, hair, and nails have been recognized in ODDD but are often easily overlooked. We report an ODDD patient with curly hair, early trichorrhexis nodosa and discrete keratoderma. Molecular genetic studies revealed a novel GJA1 mutation affecting the amino terminus of the gap junction protein alpha-1 (Cx43). In the light of the cutaneous findings in our patient and based on recent ectodermal dysplasia classification systems, we propose to include ODDD in the group of ectodermal dysplasias. PMID:16709485
Kelly, Susan C; Ratajczak, Paulina; Keller, Matthew; Purcell, Stephen M; Griffin, Thomas; Richard, Gabriele
Exposure to hair dyes has long been known as a significant risk factor for development of allergic contact dermatitis among the exposed population as these lead to severe eczema of face and upper trunk in the consumer and hand eczema in hair-dressers. Currently, para-phenylenediamine (PPD) is the main ingredient used in permanent hair color products in the market and is the most important allergen. Prevalence of PPD sensitization is high in patients with contact dermatitis across all continents, with hair dye use being the commonest cause. In order to decrease the burden of disease, use of alternative natural dyeing agents among consumers and use of barrier neoprene gloves among hairdressers should be encouraged apart from stringent legislation to reduce the amount of PPD reaching the consumer. PMID:22960813
Handa, Sanjeev; Mahajan, Rahul; De, Dipankar
The health and beauty of human hair have immeasurable psychological importance. Hair structure and its cycle are influenced by intentionally or nonintentionally delivered factors such as grooming, heat styling, chemical agents and climatic exposure. All of these factors are capable of causing loss of hair color and luster, harshness, stiffness, weakness, brittleness and flyaway, transient loss of hair or scarring
Niemann-Pick Type C disease is an autosomal recessive neurodegenerative disorder with abnormal lipid storage as the major cellular pathologic hallmark. Genetic analyses have identified mutations in NPC1 gene in the great majority of cases, while mutations in NPC2 account for the remainders. Yet, little is known regarding the cellular mechanisms responsible for NPC pathogenesis, especially for neurodegeneration, which is the usual cause of death. To identify critical steps that could account for the pathological manifestations of the disease in one of the most affected brain structures, we performed global gene expression analysis in the cerebellum from three-week old Npc1+/+ and Npc1-/- mice with two different microarray platforms (Agilent and Illumina). Differentially-expressed genes identified by both microarray platforms were then subjected to KEGG pathway analysis. Expression of genes in six pathways was significantly altered in Npc1-/- mice; functionally, these signaling pathways belong to the following three categories: 1) steroid and terpenoid biosynthesis, 2) immune response, and 3) cell adhesion/motility. In addition, the expression of several proteins involved in lipid transport was significantly altered in Npc1-/- mice. Our results provide novel molecular insight regarding the mechanisms of pathogenesis in NPC disease and reveal potential new therapeutic targets.
Liao, Guanghong; Wen, Zhining; Irizarry, Kristopher; Huang, Ying; Mitsouras, Katherine; Darmani, Mariam; Leon, Terry; Shi, Leming; Bi, Xiaoning
Myeloid and lymphoid malignancies associated with fibroblast growth factor receptor-1 (FGFR1) abnormalities are characterized by constitutively activated FGFR1 kinase and rapid transformation to acute myeloid leukemia and lymphoblastic lymphoma. Molecular targeted therapies have not been widely used for stem cell leukemia/lymphoma (SCLL). Ponatinib (AP24534), which potently inhibits native and mutant BCR-ABL, also targets the FGFR family. Using murine BaF3 cells, stably transformed with six different FGFR1 fusion genes, as well as human KG1 cells expressing activated chimeric FGFR1 and five newly established murine SCLL cell lines, we show that ponatinib (<50 nM) can effectively inhibit phosphoactivation of the fusion kinases and their downstream effectors, such as PLC?, Stat5 and Src. Ponatinib also significantly extended survival of mice transplanted with different SCLL cell lines. Ponatinib administered at 30 mg/kg daily also significantly delayed, or even prevented, tumorigenesis of KG1 cells in xenotransplanted mice. Furthermore, we demonstrate that ponatinib specifically inhibits cell growth and clonogenicity of normal human CD34+ progenitor cells transformed by chimeric FGFR1 fusion kinases. Overall, our data provide convincing evidence to suggest that pharmacologic inhibition of FGFR1 fusion kinases with ponatinib is likely to be beneficial for patients with SCLL and perhaps for other human disorders associated with dysregulated FGFR1 activity. PMID:22781593
Ren, M; Qin, H; Ren, R; Cowell, J K
Introduction There are major new advancements in the fields of stem cell biology, developmental biology, regenerative hair cycling, and tissue engineering. The time is ripe to integrate, translate and apply these findings to tissue engineering and regenerative medicine. Readers will learn about new progress in cellular and molecular aspects of hair follicle development, regeneration and potential therapeutic opportunities these advances may offer. Areas covered Here we use hair follicle formation to illustrate this progress and to identify targets for potential strategies in therapeutics. Hair regeneration is discussed in four different categories. (1) Intra-follicle regeneration (or renewal) is the basic production of hair fibers from hair stem cells and dermal papillae in existing follicles. (2) Chimeric follicles via epithelial-mesenchymal recombination to identify stem cells and signaling centers. (3) Extra-follicular factors including local dermal and systemic factors can modulate the regenerative behavior of hair follicles, and may be relatively easy therapeutic targets. (4) Follicular neogenesis means the de novo formation of new follicles. In addition, scientists are working to engineer hair follicles, which require hair forming competent epidermal cells and hair inducing dermal cells. Expert opinion Ideally self-organizing processes similar to those occurring during embryonic development should be elicited with some help from biomaterials.
Chueh, Shan-Chang; Lin, Sung-Jan; Chen, Chih-Chiang; Lei, Mingxing; Wang, Ling Mei; Widelitz, Randall B.; Hughes, Michael W.; Jiang, Ting-Xing; Chuong, Cheng Ming
Dermatoscopy is a noninvasive diagnostic tool that allows the recognition of morphologic structures not visible by the naked eye. Trichoscopy (scalp dermatoscopy and videodermatoscopy) is useful for the diagnosis and follow-up of hair and scalp disorders. However, it is not widely used in the management of hair disorders. This review provides updated information from the literature and our experience on the dermoscopic features of the most common hair and scalp disorders. This will enable dermatologists to make fast diagnoses of tinea capitis and alopecia areata, distinguish early androgenetic alopecia from telogen effluvium, and differentiate scarring from nonscarring alopecia. PMID:22405573
Miteva, Mariya; Tosti, Antonella
Purpose of review This review covers papers published between 2010 and early 2011 that presented new findings on inner ear-efferents and their ability to modulate hair cell function. Recent findings Studies published within the review period have increased our understanding of efferent mechanisms on hair cells in the cochlear and vestibular sensory epithelium and provide insights on efferent contributions to the plasticity of bilateral auditory processing. The central nervous system controls the sensitivity of hair cells to physiological stimuli by regulating the gain of hair cell electromechanical amplification and modulating the efficiency of hair cell-8th nerve transmission. A notable advance in the past year has been animal and human studies that have examined the contribution of the olivocochlear efferents to sound localization particularly in a noisy environment. Summary Acoustic activation of olivocochlear fibers provides a clinical test for the integrity of the peripheral auditory system and has provided new understanding about the function and limitations of the cochlear amplifier. While similar tests may be possible in the efferent vestibular system they have not yet been developed. The structural and functional similarities of the sensory epithelia in the inner ear offer hope that testing procedures may be developed that will allow reliable testing of the vestibular hair cell function.
RABBITT, RICHARD D.; BROWNELL, WILLIAM E.
Crickets and other orthopteran insects sense air currents with a pair of abdominal appendages resembling antennae, called cerci. Each cercus in the common house cricket Acheta domesticus is covered with between 500 to 750 filiform mechanosensory hairs. The distribution of the hairs on the cerci, as well as the global patterns of their movement axes, are very stereotypical across different animals in this species, and the development of this system has been studied extensively. Although hypotheses regarding the mechanisms underlying pattern development of the hair array have been proposed in previous studies, no quantitative modeling studies have been published that test these hypotheses. We demonstrate that several aspects of the global pattern of mechanosensory hairs can be predicted with considerable accuracy using a simple model based on two independent morphogen systems. One system constrains inter-hair spacing, and the second system determines the directional movement axes of the hairs.
Heys, Jeffrey J.; Rajaraman, Prathish K.; Gedeon, Tomas; Miller, John P.
The cuticular hairs and sensory bristles that decorate the adult Drosophila epidermis and the denticles found on the embryo have been used in studies on planar cell polarity and as models for the cytoskeletal mediated morphogenesis of cellular extensions. ZP domain proteins have recently been found to be important for the morphogenesis of both denticles and bristles. Here we show that the ZP domain protein Dusky-like is a key player in hair morphogenesis. As is the case in bristles, in hairs dyl mutants display a dramatic phenotype that is the consequence of a failure to maintain the integrity of the extension after outgrowth. Hairs lacking dyl function are split, thinned, multipled and often very short. dyl is required for normal chitin deposition in hairs, but chitin is not required for the normal accumulation of Dyl, hence dyl acts upstream of chitin. A lack of chitin however, does not mimic the dyl hair phenotype, thus Dyl must have other targets in hair morphogenesis. One of these appears to be the actin cytoskeleton. Interestingly, dyl mutants also display a unique planar cell polarity phenotype that is distinct from that seen with mutations in the frizzled/starry night or dachsous/fat pathway genes. Rab11 was previously found to be essential for Dyl plasma membrane localization in bristles. Here we found that the expression of a dominant negative Rab11 can mimic the dyl hair morphology phenotype consistent with Rab11 also being required for Dyl function in hairs. We carried out a small directed screen to identify genes that might function with dyl and identified Chitinase 6 (Cht6) as a strong candidate, as knocking down Cht6 function led to weak versions of all of the dyl hair phenotypes. PMID:23623898
Adler, Paul N; Sobala, Lukasz F; Thom, Desean; Nagaraj, Ranganayaki
Early postnatal mouse cochlear cultures were treated with a small panel of kinase inhibitors to elucidate the mechanisms underlying the maintenance of hair-bundle structure in the developing inner ear. At low concentrations (1-10 nM), staurosporine causes the collapse and loss of hair bundles without provoking hair-cell death, as judged by lack of terminal transferase dUTP nick end labeling (TUNEL) labeling or reactivity to anti-activated caspase-3. Staurosporine exposure results in the fusion of the hair bundle's stereocilia, a resorption of the parallel actin bundles of the stereocilia into the cytoplasm of the hair cell, a detachment of the apical, non-stereociliary membrane of the hair cell from the underlying cuticular plate, and a severing of the hair-bundle's rootlets from the actin cores of the stereocilia. It does not block membrane retrieval at the apical pole of the hair cells, nor does it elicit the externalization of phosphatidylserine. Staurosporine treatment causes a reduction in levels of the phosphorylated forms of ezrin, radixin, and moesin in cochlear cultures during the period of hair-bundle loss, indicating the integrity of the hair bundle may be actively maintained by the phosphorylation status of these proteins. J. Comp. Neurol. 522:3281-3294, 2014. © 2014 Wiley Periodicals, Inc. PMID:24700109
Goodyear, Richard J; Ratnayaka, Helen S K; Warchol, Mark E; Richardson, Guy P
Chrysanthemum zawadskii has been proven to possess hair growth activity and has been used as treatment for hair loss. The aim of this study was to provide a novel explanation of the mechanism by which Chrysanthemum zawadskii extracts (CZe) promote hair growth and to characterize the affected hair follicle (HF) regions and the progression of growth. The n-butanol and water fractions of CZe were used for hair growth induction by topical application to the backs of C57BL/6 mice for up to 30 days. To investigate cell development during HF morphogenesis, bromodeoxyuridine-labeled skin sections were detected using immunohistochemistry. The results showed that the water fraction of CZe promoted hair shaft production and induced premature entry of telogen HFs into the anagen. Subsequently, immunohistochemical studies indicated that the water fraction of CZe stimulated the differentiation and proliferation of pluripotent epidermal matrix cells in the matrix region and epithelial stem cells in the basal layer of the epidermis. Additionally, flavonoids were identified as effective constituents. Therefore, the findings of this study suggested that the water fraction of CZe may be developed as a therapeutic agent for the prevention of hair loss. PMID:24807783
Li, Zheng; Li, Jingjie; Gu, Lijuan; Begum, Shahnaz; Wang, Yunbo; Sun, Baishen; Lee, Mira; Sung, Changkeun
Hair cells of the mammalian cochlea are specialized for the dynamic coding of sound stimuli. The transduction of sound waves into electrical signals depends upon mechanosensitive hair bundles that project from the cell's apical surface. Each stereocilium within a hair bundle is composed of uniformly polarized and tightly packed actin filaments. Several stereociliary proteins have been shown to be associated with hair bundle development and function and are known to cause deafness in mice and humans when mutated. The growth of the stereociliar actin core is dynamically regulated at the actin filament barbed ends in the stereociliary tip. We show that Eps8, a protein with actin binding, bundling, and barbed-end capping activities in other systems, is a novel component of the hair bundle. Eps8 is localized predominantly at the tip of the stereocilia and is essential for their normal elongation and function. Moreover, we have found that Eps8 knockout mice are profoundly deaf and that IHCs, but not OHCs, fail to mature into fully functional sensory receptors. We propose that Eps8 directly regulates stereocilia growth in hair cells and also plays a crucial role in the physiological maturation of mammalian cochlear IHCs. Together, our results indicate that Eps8 is critical in coordinating the development and functionality of mammalian auditory hair cells.
Waldhaus, Jorg; Xiong, Hao; Hackney, Carole M.; Holley, Matthew C.; Offenhauser, Nina; Di Fiore, Pier Paolo; Knipper, Marlies; Masetto, Sergio; Marcotti, Walter
Alterations to the metabolic environment during puberty can impact future lactation efficiency and mammary tumorigenesis. During this study, we used a model of rabbits receiving an obesogenic diet (OD), starting before puberty and extending until mid-pregnancy. Three months later, the body weight of OD animals was significantly higher than that of controls and their mammary glands displayed a precocious and abnormal development at mid-pregnancy. OD mammary ducts were filled with dense products, while alveolar structures invaded most of the fat pad. The proportion of secretory epithelium was significantly higher in OD mammary tissue, which contained an abundant accumulation of milk proteins and lipids. In conclusion, an obesogenic diet started before puberty induced an accelerated development of the rabbit mammary gland, leading to an accumulation of secretory products at mid-pregnancy. These results support the critical influence of nutrition on mammary growth and differentiation, which may be deleterious to mammary development and subsequent lactation. PMID:21246651
Hue-Beauvais, Cathy; Chavatte-Palmer, Pascale; Aujean, Etienne; Dahirel, Michèle; Laigre, Patrice; Péchoux, Christine; Bouet, Stephan; Devinoy, Eve; Charlier, Madia
The stress hormone cortisol (CORT) is slowly incorporated into the growing hair shaft of humans, nonhuman primates, and other mammals. We developed and validated a method for CORT extraction and analysis from rhesus monkey hair and subsequently adapted this method for use with human scalp hair. In contrast to CORT "point samples" obtained from plasma or saliva, hair CORT provides an integrated measure of hypothalamic-pituitary-adrenocortical (HPA) system activity, and thus physiological stress, during the period of hormone incorporation. Because human scalp hair grows at an average rate of 1 cm/month, CORT levels obtained from hair segments several cm in length can potentially serve as a biomarker of stress experienced over a number of months. In our method, each hair sample is first washed twice in isopropanol to remove any CORT from the outside of the hair shaft that has been deposited from sweat or sebum. After drying, the sample is ground to a fine powder to break up the hair's protein matrix and increase the surface area for extraction. CORT from the interior of the hair shaft is extracted into methanol, the methanol is evaporated, and the extract is reconstituted in assay buffer. Extracted CORT, along with standards and quality controls, is then analyzed by means of a sensitive and specific commercially available enzyme immunoassay (EIA) kit. Readout from the EIA is converted to pg CORT per mg powdered hair weight. This method has been used in our laboratory to analyze hair CORT in humans, several species of macaque monkeys, marmosets, dogs, and polar bears. Many studies both from our lab and from other research groups have demonstrated the broad applicability of hair CORT for assessing chronic stress exposure in natural as well as laboratory settings. PMID:24513702
Meyer, Jerrold; Novak, Melinda; Hamel, Amanda; Rosenberg, Kendra
Methods of objectively assessing the growth rate of hairs in hirsute women have generally required some form of shaving and have focused on studying hairs affecting the face, which has reduced the number of patients willing or able to participate in such studies. A possible solution is to assess the terminal hairs on the lower abdomen (ie, the male escutcheon) because these two body areas are the most frequently affected with excess hair growth in hirsute patients. Nonetheless, it is unclear how the growth characteristics (density, diameter, and growth rate) of the hairs on the abdomen and face differ in these patients. We hypothesize that the growth characteristics of terminal hairs on the abdomen and face are similar and that evaluation of either area may be sufficient in assessing the hair growth rate of these patients. To objectively evaluate hair growth in the face and abdomen in hirsute patients, we developed a computer-aided image analysis system capable of measuring several growth parameters. Twenty hirsute women (12 white and 8 black), aged 31.2 +/- 6.1 years, were studied. Facial and abdominal skin areas were shaved, and 3 to 5 days later the areas were photographed through a calibrated glass plate and 5 terminal hairs were plucked from each area. The daily hair growth rate (assessed by photography and by direct measurement of the plucked hair), the density of hairs (number of hairs per surface area assessed by photography), and hair diameter (of the plucked hairs) were determined. The extent of hirsutism was also measured, albeit subjectively, by a modification of the Ferriman-Gallwey method, with each area given a score of 0 (no terminal hairs seen) to 4 (terminal hairs in a pattern similar to that of a very hirsute man). Facial, abdominal, and total Ferriman-Gallwey scores were 1.3 +/- 0.6, 1.8 +/- 0.9, and 12.5 +/- 5.4, respectively. Our results indicated that facial hairs were distributed in greater density and had a greater diameter than abdominal hairs (15.6 +/- 14.2 hairs/cm(2) vs 5.4 +/- 1.9 hairs/cm(2), and 84.5 +/- 19.5 microm and 66.2 +/- 17.5 microm, respectively, P <.005). Alternatively, the growth rates of facial and abdominal hairs were similar, whether determined photographically (0.36 +/- 0.18 mm/day vs 0.43 +/- 0.19 mm/day, respectively) or from plucked hairs (1.2 +/- +0.2 mm/d vs 1.4 + 0.4 mm/d, respectively). We conclude that although the density and diameter of facial hairs are greater than that of lower abdominal hairs, these areas have very similar growth rates. Hence evaluation of either of the body areas, using an objective method of assessing hair growth, should provide equivalent results. PMID:11712028
Hines, G; Moran, C; Huerta, R; Folgman, K; Azziz, R
Loose anagen syndrome (LAS) is a benign, self-limiting condition where anagen hairs are easily and painlessly extracted. It is mainly reported in childhood; however, it may variably present in adulthood as well. The presence of anagen hair devoid of its sheath and with ‘floppy sock appearance’ is a characteristic feature of loose anagen hair (LAH) on trichogram. LAH can be seen in normal population and in alopecia areata. The percentage of LAH in LAS is more than 50%. The histopathological findings show clefting between the layers of hair and are very useful in differentiating LAS from alopecia areata. Here, a review on the diagnostic criteria and practical guidelines are discussed so as to enable the trichologist in managing this benign, self-limiting condition and differentiating it from the other causes of non-scarring alopecias.
Dhurat, Rachita P; Deshpande, Deepal J
... MS, Dover JS, Arndt KA, editors. Atlas of Cosmetic Surgery . United States of America, W. B. Saunders Company; ... of Dermatology Dermatologists have invented or refined several cosmetic procedures. Hair replacement and transplant surgery was pioneered by an American dermatologist.
Background: Today, human iodine deficiency is, after iron, the most common nutritional deficiency in developed European and underdeveloped third world countries. A current biological indicator of iodine status is urinary iodine, which reflects very recent iodine exposure; a long-term indicator of iodine status remains to be identified. Methods: We analyzed hair iodine in a prospective, observational, cross-sectional, and exploratory study involving 870 apparently healthy Croatians (270 men and 600 women). Hair iodine was analyzed with inductively coupled plasma mass spectrometry. Results: The hair iodine median was 0.499??g/g, and was 0.482 and 0.508??g/g for men and women respectively, suggesting no sex-related difference. We studied hair iodine uptake by analyzing the logistic sigmoid saturation curve of the median derivatives to assess iodine deficiency, adequacy, and excess. We estimated overt iodine deficiency to occur when hair iodine concentration was below 0.1-0.15??g/g. Then there was a saturation range interval of about 0.1-2.0??g/g where the deposition of iodine in the hair was linearly increasing (R(2)=0.994). Eventually, the sigmoid curve became saturated at about 2.0??g/g and upward, suggesting excessive iodine exposure. Conclusion: Hair appears to be a valuable and robust biological indicator tissue for assessing long-term iodine status. We propose that an adequate iodine status corresponds with hair iodine uptake saturation of 0.565-0.739??g/g (55-65%). PMID:24446669
Mom?ilovi?, Berislav; Prejac, Juraj; Višnjevi?, Vjeran; Skalnaya, Margarita G; Mimica, Ninoslav; Drmi?, Stipe; Skalny, Anatoly V
In the late 1960s, tissue recombination studies by Roy Oliver on the model of rat vibrissae provided invaluable information about the morphogenetic properties of hair follicles. Now more than ever, the field is hopeful that a clinically reproducible procedure for cell-based hair regeneration is achievable. Highly inductive mesenchymal cells are thought to be the key ingredient necessary to achieve robust hair regeneration, and efforts are underway to develop protocols to improve the naturally low inductive properties of human dermal papilla cells. In this respect, the original studies by Oliver provide essential rodent research benchmarks, which current-day human studies should aim to reach. PMID:24494858
Plikus, Maksim V
Chemotherapy-induced alopecia is a major problem in clinical oncology. Doxorubicin, a widely used cancer chemotherapy drug, induces disruption of the hair cycle and subsequent alopecia. We show in this report that doxorubicin causes disruption of the hair-follicle-associated blood vessel network resulting in a greatly reduced density of these blood vessels. Dystrophic hair follicles were also observed with abnormal melanogenesis in the mice treated with doxorubicin. Visualization of the effect of doxorubicin on hair-follicle angiogenesis was made possible by the use of transgenic mice in which green fluorescent protein was driven by regulatory elements of the nestin gene (ND-GFP). In these transgenic mice, the hair-follicle stem cells and the follicle structure as well as the blood vessels associated with the hair follicles express ND-GFP. The hair-follicle stem cells did not appear to be affected by doxorubicin, which may explain why hair regrows after chemotherapy. These results suggest that inhibition of hair-follicle-associated angiogenesis by doxorubicin may be an important factor in hair-follicle dystrophy associated with chemotherapy-induced alopecia. The ND-GFP mouse model is thus useful for the study of the role of angiogenesis in the hair-follicle cycle and the effect of drugs on processes associated with chemotherapy-induced alopecia. PMID:16841031
Amoh, Yasuyuki; Li, Lingna; Katsuoka, Kensei; Hoffman, Robert M
Inner hair cells (IHCs), the primary sensory receptors of the mammalian cochlea, fire spontaneous Ca2+ action potentials before the onset of hearing. Although this firing activity is mainly sustained by a depolarizing L-type (CaV1.3) Ca2+ current (ICa), IHCs also transiently express a large Na+ current (INa). We aimed to investigate the specific contribution of INa to the action potentials, the nature of the channels carrying the current and whether the biophysical properties of INa differ between low- and high-frequency IHCs. We show that INa is highly temperature-dependent and activates at around ?60 mV, close to the action potential threshold. Its size was larger in apical than in basal IHCs and between 5% and 20% should be available at around the resting membrane potential (?55 mV/?60 mV). However, in vivo the availability of INa could potentially increase to >60% during inhibitory postsynaptic potential activity, which transiently hyperpolarize IHCs down to as far as ?70 mV. When IHCs were held at ?60 mV and INa elicited using a simulated action potential as a voltage command, we found that INa contributed to the subthreshold depolarization and upstroke of an action potential. We also found that INa is likely to be carried by the TTX-sensitive channel subunits NaV1.1 and NaV1.6 in both apical and basal IHCs. The results provide insight into how the biophysical properties of INa in mammalian cochlear IHCs could contribute to the spontaneous physiological activity during cochlear maturation in vivo.
Eckrich, Tobias; Varakina, Ksenya; Johnson, Stuart L.; Franz, Christoph; Singer, Wibke; Kuhn, Stephanie; Knipper, Marlies; Holley, Matthew C.; Marcotti, Walter
The hair cycle consisting of growing and resting phases, is subject to widespread disease such as androgenic alopecia or loss of pigment which are in need of effective, targeted therapeutics. In order to develop a hair-follicle delivery system we demonstrate here that phosphatidylcholine liposomes entrapping either the fluorescent dye calcein or the pigment melanin can deliver these molecules into the hair follicle and hair shafts of mice when applied topically. Liposomal delivery of these molecules is time dependent. Negligible amounts of delivered molecules enter the dermis, epidermis or blood stream thereby demonstrating the enrichment of follicle delivery. Naked calcein and melanin are trapped in the stratum corneum and are unable to enter the follicle. The potential of the hair-follicle liposome delivery system for therapeutic use for hair disease is discussed. PMID:9039973
Li, L; Hoffman, R M
Hair tourniquet syndrome has been recognized as a medical entity since the 1600 s. Appendages develop acute ischemia from tightening of hair strands circumferentially wrapped around them. Most commonly affected sites are fingers, toes, and penis, but limited reports have described involvement of the female genitalia. Although hair strangulation involving the labia minora or clitoris has been described, it typically occurs in young children. We present a case of an adolescent girl with a labial appendage hair tourniquet resulting from a previous unrepaired genital laceration. This is one of the oldest patients in whom a genital hair tourniquet has been reported, as well as description of a posttraumatic genital appendage. Genital hair tourniquets are medical emergencies that require prompt diagnosis and treatment to avoid tissue necrosis and possible amputation. Genital trauma in general requires surgical evaluation. PMID:23823263
Dua, Anahita; Jamshidi, Ramin; Lal, Dave R
Afro-ethnic hair, when compared with naturally straight hair, presents some important variations such as differences in diameter in many points of the thread, ellipsoidal threads, and low trend of hydrating the scalp thus turning the hair drier, because the natural sebum distribution is irregular along the thread. This kind of hair may be straightened through both chemical and thermal methods. Straightening is a chemical process by which excessively curly hair is straightened in an irreversible way. Generally, the products used are formulated in a cosmetic emulsion with high pH. In this review, we present the historical development of hair straightening or relaxing through the evolution of the product categories. PMID:17348987
de Sá Dias, Tania Cristina; Baby, André Rolim; Kaneko, Telma Mary; Robles Velasco, Maria Valéria
Owing to the tight control of methamphetamine, it is presumed that phentermine, an amphetamine-type anorectic, has recently been considered a supplement for methamphetamine abusers in Korea. In addition, the abuse of other anorectics obtained by inappropriate means has become a social issue. Hair is a useful specimen to prove chronic drug use. Therefore, an analytical method for the simultaneous detection of phentermine, phendimetrazine, amfepramone, fenfluramine, mazindol, methamphetamine, and 3,4-methylenedioxymethamphetamine (MDMA), as well as their metabolites, which covers the major amphetamines and anorectic agents in Korea, in hair was established and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The drugs and their metabolites in hair were extracted using 1 % HCl in methanol and then filtered and analyzed by LC-MS/MS with electrospray ionization in positive mode. The validation results for selectivity, linearity, matrix effect, recovery, process efficiency, intra- and interassay precision and accuracy, and processed sample stability were satisfactory. The limits of detection ranged from 0.025 to 1 ng/10 mg hair and the limits of quantification were 0.25 ng/10 mg hair for every analyte except mazindol and phentermine, for which they were 10 ng/10 mg hair. The method was successfully applied for the segmental determination of selected anorectics, methamphetamine, MDMA, and their metabolites in hair from 39 drug suspects. Among the anorectics, phentermine and/or phendimetrazine were identified with or without methamphetamine in the hair samples. Closer supervision of the inappropriate use of anorectics is necessary. Also, hair analysis is useful for monitoring the abuse potential of unnoticed drugs. PMID:22460079
Lee, Sooyeun; Kim, Jihyun; In, Sanghwan; Choi, Hwakyung; Oh, Seung Min; Jang, Choon-Gon; Chung, Kyu Hyuck
Loose anagen hair syndrome (LAHS) is an uncommonly reported autosomal dominant hair disorder with incomplete penetrance that primarily affects children but is occasionally seen in adults. LAHS is characterized by the ability to easily and painlessly extract unsheathed anagen hairs from the scalp with gentle traction. The hair is sparse and does not grow long. Usually the hairs are not fragile and do not have areas of breakage. Initially it was considered a rare, sporadic condition found predominantly in young white girls with blonde hair. Because autosomal dominant inheritance has been reported, it was suspected that the condition might be equally common in boys but was probably underdiagnosed. PMID:23937400
Dey, Vivek; Thawani, Manasi
In this study, we have developed a single hair fiber torsional pendulum method to determine the role of the cuticle and the cortex on torsional properties with respect to fiber cross-sectional area, fiber rigidity, and energy dissipation at 65% RH and in the wet state. Our results demonstrate that in fine diameter fibers with a high cuticle-to-cortex ratio, the cuticula exert a significant effect on the torsional deformation behavior of hair fibers at both normal humidities and in the wet condition. In addition, our data indicate that energy dissipation is confined to fibers with a high cuticle-to-cortex ratio, and the amount of energy dissipated becomes more pronounced with increasing water content. The torsional properties of hair spray-treated fibers suggest that the deposited hair spray film masks the properties of the base fiber and imparts its own dissipative character to the measurement. Since tensile mechanical properties are often used to make claims about the performance of hair care products, we have compared the results obtained from torsional and tensile measurements on over-processed bleached hair fibers conditioned with Polyquaternium-10 and cetyl trimethylammonium bromide (CETAB) to evaluate which method is more advantageous. Our data demonstrate that torsional measurements can distinguish hair care products which reinforce the cuticle from those which affect the cortex, while tensile measurements showed no significant differences. PMID:15645103
Persaud, D; Kamath, Y K
Eruptive vellus hair cysts were first described in 1977. They usually appear as yellow to reddish-brown papules on the chest. Usual onset is between ages 17 and 24 years, but they may be congenital. Some believe that they may be inherited as an autosomal dominant disorder. Histologically the cyst has a stratified squamous epithelium and it contains laminated keratin and vellus hairs. They are felt to be caused by an abnormality at the infundibular level of the vellus hair. We present this because of this patient's unusual distribution of eruptive vellus hair cysts.
Khatu, Swapna; Vasani, Resham; Amin, Shital
Anomalie m.p. is a spontaneous and heritable hindlimb abnormality described earlier. Twenty years later, Pleurodeles waltl larvae from the strain bearing anomalie m.p. and reared at room temperature or at 30 degrees C, expressed abnormalities (ectrodactylia, hemimelia, ectromelia). A morphological study of all the hindlimbs and an analysis of the hindlimb skeleton of samples from the experimental animals confirmed that most of the skeletal malformations were identical to those previously reported and affected the disto-proximal and prepostaxial pattern of the hindlimb. Analysis of the effects of rearing temperature on the expression of anomalie m.p. showed that the effects varied according to the developmental period at which the heat treatment was applied; the sooner the heat treatment began, the more numerous and more various were the degrees of severity of the malformations. Moreover, heat treatment induced the expression of two additional malformations not yet described: the first one, named 'reversed knee joint', was characterized by a reversal of the knee joint, and the second one, named 'twisted foot', by a downward twisting of the foot. The epigenetic effects of rearing at 30 degrees C on hindlimb development are discussed with regard to the differentiation or patterning. PMID:9783481
Dournon, C; Bautz, A; Membre, H; Lauthier, M; Collenot, A
Summary Steroid hormones modulate memory in animals and human adults. Little is known on the developmental effect of these hormones on the neural networks underlying memory. Using Congenital Adrenal Hyperplasia (CAH) as a naturalistic model of early steroid abnormalities, this study examines the consequences of CAH on memory and its neural correlates for emotionally arousing and neutral material in children. Seventeen patients with CAH and 17 age- and sex-matched healthy children (ages 12 to 14 years) completed the study. Subjects were presented positive, negative and neutral pictures. Memory recall occurred about 30 minutes after viewing the pictures. Children with CAH showed memory deficits for negative pictures compared to healthy children (p < 0.01). There were no group differences on memory performance for either positive or neutral pictures (p’s >0.1). In patients, 24h urinary-free cortisol levels (reflecting glucocorticoid replacement therapy) and testosterone levels were not associated with memory performance. These findings suggest that early steroid imbalances affect memory for negative material in children with CAH. Such memory impairments may result from abnormal brain organization and function following hormonal dysfunction during critical periods of development.
Maheu, Francoise S.; Merke, Deborah P.; Schroth, Elizabeth A.; Keil, Margaret F.; Hardin, Julie; Poeth, Kaitlin; Pine, Daniel S.; Ernst, Monique
In mammals, hair cell loss causes irreversible hearing and balance impairment because hair cells are terminally differentiated and do not regenerate spontaneously. By profiling gene expression in developing mouse vestibular organs, we identified the retinoblastoma protein (pRb) as a candidate regulator of cell cycle exit in hair cells. Differentiated and functional mouse hair cells with a targeted deletion of Rb1 undergo mitosis, divide, and cycle, yet continue to become highly differentiated and functional. Moreover, acute loss of Rb1 in postnatal hair cells caused cell cycle reentry. Manipulation of the pRb pathway may ultimately lead to mammalian hair cell regeneration.
Sage, Cyrille; Huang, Mingqian; Karimi, Kambiz; Gutierrez, Gabriel; Vollrath, Melissa A.; Zhang, Duan-Sun; García-Añoveros, Jaime; Hinds, Philip W.; Corwin, Jeffrey T.; Corey, David P.; Chen, Zheng-Yi
Coordinated regulation of the many genes controlling leaf, flower, and root development determines the phenotypes of plants; this regulation requires exquisite control of many transcription factors, including the WUSCHEL-related homeobox (WOX) family. We recently reported that rice (Oryza sativa) WUSCHEL-related homeobox 3A (OsWOX3A) plays important roles in organ development, including lateral-axis outgrowth and vasculature patterning in leaves, lemma and palea morphogenesis in spikelets, and the numbers of tillers and lateral roots. OsWOX3A is encoded by NARROW LEAF2 (NAL2) and NAL3, a pair of duplicated genes. In this study, further analysis of nal2 nal3 (hereafter nal2/3) double mutants revealed that, in addition to its role in lateral root development, OsWOX3A also acts in the control of root hair formation. Based on this new finding, we describe a possible mechanism by which OsWOX3A regulation of auxin transport genes acts in root development. PMID:24002214
Yoo, Soo-Cheul; Cho, Sung-Hwan; Paek, Nam-Chon
The goals of our work are to develop means of identifying cells, and individuals, that present with a more basal oxidized redox state and to identify molecular mechanisms that functionally integrate such an oxidized state with observations that the multip...
M. D. Noble
The goals of our work are to develop means of identifying cells, and individuals, that present with a more basal oxidized redox state and to identify molecular mechanisms that functionally integrate such an oxidized state with observations that the multip...
M. D. Noble
We hypothesize that low systemic redox potential (GSH/GSSG; cysteine/cystine) reflects a vulnerability phenotype that is associated with regressive autism and is predictive of the risk of developing autism. The redox vulnerability phenotype is associated ...
S. J. James
BackgroundWe postulated that during ontogenesis cortical surface area and cerebral volume are related by a scaling law whose exponent gives a quantitative measure of cortical development. We used this approach to investigate the hypothesis that premature termination of the intrauterine environment by preterm birth reduces cortical development in a dose-dependent manner, providing a neural substrate for functional impairment.Methods and FindingsWe
Olga Kapellou; Serena J. Counsell; Nigel Kennea; Leigh Dyet; Nadeem Saeed; Jaroslav Stark; Elia Maalouf; Philip Duggan; Morenike Ajayi-Obe; Jo Hajnal; Joanna M. Allsop; James Boardman; Mary A. Rutherford; Frances Cowan; A. David Edwards
The present study was designed to investigate whether the formation of the cranial flexure is involved in the normal positional changes of the embryonic heart tube that occur during its transformation from the c- to s-shaped loop. For this purpose, the formation of the cranial flexure was locally suppressed in chick embryos by introducing a straight hair into the neural canal. In the experimental embryos, prevention of cranial flexure did not suppress the normal positional changes of the heart tube. However, other anomalies in the looping of the heart tube were frequently observed. These anomalies were caused by alterations in the formation of the ventral thoracic wall, which in turn seemed to be related not to the prevention of the cranial flexure but rather to accidental injuries during the implantation of the hair. In the embryos with abnormal looping of the heart tube, the incidence of delayed/defective septation of the heart was significantly higher than in embryos with normal looping. These results show that in the chick embryo: (1) cranial flexure is not involved in normal positional changes of the heart loop; (2) manipulations at the head region of the embryo can unintentionally result in developmental disorders of the ventral thoracic wall; (3) such disorders can result in congenital heart defects through mechanical interference with normal looping of the embryonic heart. The possible significance of these findings for the evaluation of experimental studies of chick embryos is discussed in the context of anomalies observed after surgical ablation of the premigratory cranial neural crest. PMID:7717534
Männer, J; Seidl, W; Steding, G
So-called abnormal pressures, subsurface fluid pressures significantly higher or lower than hydrostatic, have excited speculation about their origin since subsurface exploration first encountered them. Two distinct conceptual models for abnormal pressures have gained currency among earth scientists. The static model sees abnormal pressures generally as relict features preserved by a virtual absence of fluid flow over geologic time. The hydrodynamic model instead envisions abnormal pressures as phenomena in which flow usually plays an important role. This paper develops the theoretical framework for abnormal pressures as hydrodynamic phenomena, shows that it explains the manifold occurrences of abnormal pressures, and examines the implications of this approach. -from Author
Neuzil, C. E.
BackgroundIn an earlier study, we identified an association between hair relaxer-induced alopecia and decreased zinc levels. This study hopes to identify if age at first exposure to hair relaxer plays a role in the development of alopecia in the small percentage of women of African descent who use hair-relaxing products for hair-straightening purposes and develop lingering, nonresolving alopecia.
A. A. Iyanda; J. I. Anetor; D. P. Oparinde
Increasing attention has been devoted to the maturation of sensory processing in the first year of life. While the development of cortical visual function has been thoroughly studied, much less information is available on auditory processing and its early disorders. The aim of this paper is to provide an overview of the assessment techniques for…
Guzzetta, Francesco; Conti, Guido; Mercuri, Eugenio
Iron is essential for organisms. It is mainly utilized in mitochondria for biosynthesis of iron-sulfur clusters, hemes and other cofactors. Mitoferrin 1 and mitoferrin 2, two homologues proteins belonging to the mitochondrial solute carrier family, are required for iron delivery into mitochondria. Mitoferrin 1 is highly expressed in developing erythrocytes which consume a large amount of iron during hemoglobinization. Mitoferrin
Yaguang Ren; Su Yang; Guoqiang Tan; Wei Ye; Danhui Liu; Xu Qian; Zhongying Ding; Yuhong Zhong; Jingrui Zhang; Dandan Jiang; Yuhong Zhao; Jianxin Lu
To elucidate the mechanisms involved in Rhizobium-legume symbiosis, we examined a novel symbiotic mutant, crinkle (Ljsym79), from the model legume Lotus japonicus. On nitrogen-starved medium, crinkle mutants inoculated with the symbiont bacterium Mesorhizobium loti MAFF 303099 showed severe nitrogen deficiency symptoms. This mutant was characterized by the production of many bumps and small, white, uninfected nodule-like structures. Few nodules were pale-pink and irregularly shaped with nitrogen-fixing bacteroids and expressing leghemoglobin mRNA. Morphological analysis of infected roots showed that nodulation in crinkle mutants is blocked at the stage of the infection process. Confocal microscopy and histological examination of crinkle nodules revealed that infection threads were arrested upon penetrating the epidermal cells. Starch accumulation in uninfected cells and undeveloped vascular bundles were also noted in crinkle nodules. Results suggest that the Crinkle gene controls the infection process that is crucial during the early stage of nodule organogenesis. Aside from the symbiotic phenotypes, crinkle mutants also developed morphological alterations, such as crinkly or wavy trichomes, short seedpods with aborted embryos, and swollen root hairs. crinkle is therefore required for symbiotic nodule development and for other aspects of plant development. PMID:12644658
Tansengco, Myra L; Hayashi, Makoto; Kawaguchi, Masayoshi; Imaizumi-Anraku, Haruko; Murooka, Yoshikatsu
To elucidate the mechanisms involved in Rhizobium-legume symbiosis, we examined a novel symbiotic mutant, crinkle (Ljsym79), from the model legume Lotus japonicus. On nitrogen-starved medium, crinkle mutants inoculated with the symbiont bacterium Mesorhizobium loti MAFF 303099 showed severe nitrogen deficiency symptoms. This mutant was characterized by the production of many bumps and small, white, uninfected nodule-like structures. Few nodules were pale-pink and irregularly shaped with nitrogen-fixing bacteroids and expressing leghemoglobin mRNA. Morphological analysis of infected roots showed that nodulation in crinkle mutants is blocked at the stage of the infection process. Confocal microscopy and histological examination of crinkle nodules revealed that infection threads were arrested upon penetrating the epidermal cells. Starch accumulation in uninfected cells and undeveloped vascular bundles were also noted in crinkle nodules. Results suggest that the Crinkle gene controls the infection process that is crucial during the early stage of nodule organogenesis. Aside from the symbiotic phenotypes, crinkle mutants also developed morphological alterations, such as crinkly or wavy trichomes, short seedpods with aborted embryos, and swollen root hairs. crinkle is therefore required for symbiotic nodule development and for other aspects of plant development.
Tansengco, Myra L.; Hayashi, Makoto; Kawaguchi, Masayoshi; Imaizumi-Anraku, Haruko; Murooka, Yoshikatsu
We previously generated a transgenic mouse model for acute promyelocytic leukemia (APL) by expressing the promyelocytic leukemia (PML)–retinoic acid receptor (RAR?) cDNA in early myeloid cells. This fusion protein causes a myeloproliferative disease in 100% of animals, but only 15–20% of the animals develop acute leukemia after a long latency period (6–13 months). PML-RAR? is therefore necessary, but not sufficient, for APL development. The coexpression of a reciprocal form of the fusion, RAR?-PML, increased the likelihood of APL development (55–60%), but did not shorten latency. Together, these results suggested that additional genetic events are required for the development of APL. We therefore evaluated the splenic tumor cells from 18 transgenic mice with APL for evidence of secondary genetic events, by using spectral karyotyping analysis. Interstitial or terminal deletions of the distal region of one copy of chromosome 2 [del(2)] were found in 1/5 tumors expressing PML-RAR?, but in 11/13 tumors expressing both PML-RAR? and RAR?-PML (P < 0.05). Leukemic cells that contained a deletion on chromosome 2 often contained additional chromosomal gains (especially of 15), chromosomal losses (especially of 11 or X/Y), or were tetraploid (P ? 0.001). These changes did not commonly occur in nontransgenic littermates, nor in aged transgenic mice that did not develop APL. These results suggest that expression of RAR?-PML increases the likelihood of chromosome 2 deletions in APL cells. Deletion 2 appears to predispose APL cells to further chromosomal instability, which may lead to the acquisition of additional changes that provide an advantage to the transformed cells.
Zimonjic, Drazen B.; Pollock, Jessica L.; Westervelt, Peter; Popescu, Nicholas C.; Ley, Timothy J.
Monoclonal antibodies (mAbs) specific for the abnormal prion protein isoform (PrPres) are indispensable for diagnosing chronic wasting disease (CWD). In this study, eight mAbs were developed by immunizing PrP knockout mice with recombinant elk PrP and an immunogenic PrP peptide. The reactivity of the mAbs to recombinant PrP and the PrP peptide was measured, and their isotypes were subsequently determined. Among them, four mAbs (B85-05, B85-08, B85-12, and B77-75) were shown by Western blotting to recognize proteinase K-treated brain homogenate derived from an elk suffering from CWD.
Jeong, Hyun-Jeong; Lee, Nak-Hyung; Lee, Joong-Bok; Park, Seung-Yong; Song, Chang-Seon; Seo, Kun-Ho; Kim, Dong-Woon; Kim, Yong-Sun
Children exposed to alcohol in utero have significantly delayed gross and fine motor skills, as well as deficiencies in reflex development. The reasons that underlie the motor deficits caused by ethanol (EtOH) exposure remain to be fully elucidated. The present study was undertaken to investigate the effects of embryonic alcohol exposure (1.5%, 2% and 2.5% EtOH) on motor neuron and
Nicole J. Sylvain; Daniel L. Brewster; Declan W. Ali
Background We postulated that during ontogenesis cortical surface area and cerebral volume are related by a scaling law whose exponent gives a quantitative measure of cortical development. We used this approach to investigate the hypothesis that premature termination of the intrauterine environment by preterm birth reduces cortical development in a dose-dependent manner, providing a neural substrate for functional impairment. Methods and Findings We analyzed 274 magnetic resonance images that recorded brain growth from 23 to 48 wk of gestation in 113 extremely preterm infants born at 22 to 29 wk of gestation, 63 of whom underwent neurodevelopmental assessment at a median age of 2 y. Cortical surface area was related to cerebral volume by a scaling law with an exponent of 1.29 (95% confidence interval, 1.25–1.33), which was proportional to later neurodevelopmental impairment. Increasing prematurity and male gender were associated with a lower scaling exponent (p < 0.0001) independent of intrauterine or postnatal somatic growth. Conclusions Human brain growth obeys an allometric scaling relation that is disrupted by preterm birth in a dose-dependent, sexually dimorphic fashion that directly parallels the incidence of neurodevelopmental impairments in preterm infants. This result focuses attention on brain growth and cortical development during the weeks following preterm delivery as a neural substrate for neurodevelopmental impairment after premature delivery.
Kapellou, Olga; Counsell, Serena J; Kennea, Nigel; Dyet, Leigh; Saeed, Nadeem; Stark, Jaroslav; Maalouf, Elia; Duggan, Philip; Ajayi-Obe, Morenike; Hajnal, Jo; Allsop, Joanna M; Boardman, James; Rutherford, Mary A; Cowan, Frances; Edwards, A. David
Background Hair graying is considered as a part of normal ageing process. Nonetheless, this process raises a significant cosmetic concern, especially among ethnic Korean elderly whose baseline hair color is black. For this reason, Korean elderly dye their hair with frequency despite the risk of dermatologic problems such as allergic contact dermatitis. Objective In this study, the authors investigate the prevalence and pattern of hair dyeing and its relation with scalp diseases in Korea. Methods Six hundred twenty subjects (330 men and 290 women) with graying hair were given a questionnaire survery and underwent a physical examination. Results Of the 620 total, 272 subjects (43.9%) dyed their hair. Hair dyeing was significantly more frequent among women than among men (p<0.001). Subjects from 50 to 69 years of age showed higher prevalence of hair dyeing when compared to either younger or older groups. Subjective self-assessment of the extent of hair graying was associated with increased prevalence of hair dyeing, that is, individuals who feel graying has advanced by more than 20% of the overall hair were much more likely to dye their hair (p<0.001). Hair dyeing did not correlate with either alopecia or scalp disease. Conclusion Our survey has found that the prevalence of hair dyeing is higher among Korean women than men. People in their fifties and sixties and people with more than 20% extent of grayness were more likely to dye their hair than otherwise. Hair dyeing was not associated with any increase in the prevalence of scalp diseases.
Jo, Seong Jin; Shin, Hyoseung; Paik, Seung Hwan; Choi, Jae Woo; Lee, Jong Hee; Cho, Soyun
Segmental analysis of hair has been used in diverse fields ranging from forensics to ecology to measure the concentration of substances such as drugs and isotopes. Multiple hairs are typically combined into a bundle for segmental analysis to obtain a high-resolution series of measurements. Individual hair strands cycle through multiple phases of growth and grow at different rates when in the growth phase. Variation in growth of hair strands in a bundle can cause misalignment of substance concentration between hairs, attenuating the primary body signal. We developed a mathematical model based on the known physiology of hair growth to describe the signal averaging caused by bundling multiple hairs for segmental analysis. The model was used to form an inverse method to estimate the primary body signal from measurements of a hair bundle. The inverse method was applied to a previously described stable oxygen isotope chronology from the hair of a murder victim and provides a refined interpretation of the data. Aspects of the reconstruction were confirmed when the victim was later identified. PMID:24793936
Remien, Christopher H; Adler, Frederick R; Chesson, Lesley A; Valenzuela, Luciano O; Ehleringer, James R; Cerling, Thure E
Id2 is a helix-loop-helix (HLH) transcription factor essential for normal development and its expression is dysregulated in many human neurological conditions. Although it is speculated that elevated Id2 levels contribute to the pathogenesis of these disorders, it is unknown whether dysregulated Id2 expression is sufficient to perturb normal brain development or function. Here, we show that mice with elevated Id2 expression during embryonic stages develop microcephaly, and that females in particular are prone to generalized tonic-clonic seizures. Analyses of Id2 transgenic brains indicate that Id2 activity is highly cell context specific: elevated Id2 expression in naive NSCs in early neuroepithelium induces apoptosis and loss of NSCs and intermediate progenitors. Activation of Id2 in maturing neuroepithelium results in less severe phenotypes and is accompanied by elevation of G1 Cyclin expression and p53 target gene expression. In contrast, activation of Id2 in committed intermediate progenitors has no significant phenotype. Functional analysis with Id2 over-expressing and Id2-null NSCs shows that Id2 negatively regulates NSC self-renewal in vivo, in contrast to previous cell culture experiments. Deletion of p53 function from Id2-transgenic brains rescues apoptosis and results in increased incidence of brain tumors. Furthermore, Id2 over-expression normalizes the increased self-renewal of p53-null NSCs, suggesting that Id2 activates and modulates the p53 pathway in NSCs. Together, these data suggest that elevated Id2 expression in embryonic brains can cause deregulated NSC self-renewal, differentiation and survival that manifest in multiple neurological outcomes in mature brains, including microcephaly, seizures, and brain tumors.
Park, H.J.; Hong, M.; Bronson, R.T.; Israel, M.A.; Frankel, W. N.; Yun, K.
Id2 is a helix-loop-helix transcription factor essential for normal development, and its expression is dysregulated in many human neurological conditions. Although it is speculated that elevated Id2 levels contribute to the pathogenesis of these disorders, it is unknown whether dysregulated Id2 expression is sufficient to perturb normal brain development or function. Here, we show that mice with elevated Id2 expression during embryonic stages develop microcephaly, and that females in particular are prone to generalized tonic-clonic seizures. Analyses of Id2 transgenic brains indicate that Id2 activity is highly cell context specific: elevated Id2 expression in naive neural stem cells (NSCs) in early neuroepithelium induces apoptosis and loss of NSCs and intermediate progenitors. Activation of Id2 in maturing neuroepithelium results in less severe phenotypes and is accompanied by elevation of G1 cyclin expression and p53 target gene expression. In contrast, activation of Id2 in committed intermediate progenitors has no significant phenotype. Functional analysis with Id2-overexpressing and Id2-null NSCs shows that Id2 negatively regulates NSC self-renewal in vivo, in contrast to previous cell culture experiments. Deletion of p53 function from Id2-transgenic brains rescues apoptosis and results in increased incidence of brain tumors. Furthermore, Id2 overexpression normalizes the increased self-renewal of p53-null NSCs, suggesting that Id2 activates and modulates the p53 pathway in NSCs. Together, these data suggest that elevated Id2 expression in embryonic brains can cause deregulated NSC self-renewal, differentiation, and survival that manifest in multiple neurological outcomes in mature brains, including microcephaly, seizures, and brain tumors. PMID:23390122
Park, Hee Jung; Hong, Mingi; Bronson, Roderick T; Israel, Mark A; Frankel, Wayne N; Yun, Kyuson
Human hair is a nanocomposite biological fiber. Hair care products such as shampoos and conditioners, along with damaging processes such as chemical dyeing and permanent wave treatments, affect the maintenance and grooming process and are important to study because they alter many hair properties. Nanoscale characterization of the cellular structure, mechanical properties, and morphological, frictional, and adhesive properties (tribological properties)
This article reports the results of using a scoring system designed for the Milani-Comparetti and Gidoni method of neurologic examination of infants. The system was used in the assessment of 999 infants from the neonatal intensive care units affiliated with the Medical College of Wisconsin. The sample included all neonates who spent more than five days in the units from 1975 to 1978. Full assessments were conducted at 6 months and at 15 to 16 months corrected gestational age; additional assessments were scheduled by the physical therapists. For data analyses, the scores from the Milani-Comparetti and Gidoni method were summed; infants were subdivided into normal, transiently abnormal, and abnormal on the basis of the summed scores. Abnormal infants were further categorized on the basis of all information available. Several data analyses were performed to test the contribution of each item in separating normal, transiently abnormal, and abnormal infants and in distinguishing one type of abnormality from another. We conclude that the scoring system is useful in quantifying the degree of abnormality, in separating normality from abnormality, and in distinguishing among types of abnormality. PMID:6611662
Ellison, P H; Browning, C A; Larson, B; Denny, J
Genome-wide association studies (GWAS) have revealed numerous associations between many phenotypes and gene candidates. Frequently, however, further elucidation of gene function has not been achieved. A recent GWAS identified 69 candidate genes associated with elevated liver enzyme concentrations, which are clinical markers of liver disease. To investigate the role of these genes in liver homeostasis, we narrowed down this list to 12 genes based on zebrafish orthology, zebrafish liver expression and disease correlation. To assess the function of gene candidates during liver development, we assayed hepatic progenitors at 48 hours post fertilization (hpf) and hepatocytes at 72 hpf using in situ hybridization following morpholino knockdown in zebrafish embryos. Knockdown of three genes (pnpla3, pklr and mapk10) decreased expression of hepatic progenitor cells, whereas knockdown of eight genes (pnpla3, cpn1, trib1, fads2, slc2a2, pklr, mapk10 and samm50) decreased cell-specific hepatocyte expression. We then induced liver injury in zebrafish embryos using acetaminophen exposure and observed changes in liver toxicity incidence in morphants. Prioritization of GWAS candidates and morpholino knockdown expedites the study of newly identified genes impacting liver development and represents a feasible method for initial assessment of candidate genes to instruct further mechanistic analyses. Our analysis can be extended to GWAS for additional disease-associated phenotypes. PMID:23813869
Liu, Leah Y; Fox, Caroline S; North, Trista E; Goessling, Wolfram
SUMMARY Genome-wide association studies (GWAS) have revealed numerous associations between many phenotypes and gene candidates. Frequently, however, further elucidation of gene function has not been achieved. A recent GWAS identified 69 candidate genes associated with elevated liver enzyme concentrations, which are clinical markers of liver disease. To investigate the role of these genes in liver homeostasis, we narrowed down this list to 12 genes based on zebrafish orthology, zebrafish liver expression and disease correlation. To assess the function of gene candidates during liver development, we assayed hepatic progenitors at 48 hours post fertilization (hpf) and hepatocytes at 72 hpf using in situ hybridization following morpholino knockdown in zebrafish embryos. Knockdown of three genes (pnpla3, pklr and mapk10) decreased expression of hepatic progenitor cells, whereas knockdown of eight genes (pnpla3, cpn1, trib1, fads2, slc2a2, pklr, mapk10 and samm50) decreased cell-specific hepatocyte expression. We then induced liver injury in zebrafish embryos using acetaminophen exposure and observed changes in liver toxicity incidence in morphants. Prioritization of GWAS candidates and morpholino knockdown expedites the study of newly identified genes impacting liver development and represents a feasible method for initial assessment of candidate genes to instruct further mechanistic analyses. Our analysis can be extended to GWAS for additional disease-associated phenotypes.
Liu, Leah Y.; Fox, Caroline S.; North, Trista E.; Goessling, Wolfram
The effects of in vivo heat exposure on gestation day (GD) 10 rat embryos were evaluated on GD 11 to determine the relationships between morphological sequelae following in vivo and in vitro exposures and between effects detected on GD 11 and those observed in postnatal day (PND) 3 pups. Anesthetized rats were exposed to 42 degrees C in a warm air incubator until their rectal temperatures reached 41 degrees C or until a rectal temperature of 42-42.5 degrees C had been maintained for 5 minutes. Heat-exposed embryos exhibited a significant decrease in growth parameters including head length, somite number, and protein content/embryo versus controls. These changes correlated well with in vitro effects from an earlier study (G.L. Kimmel et al., '93). Among the morphological endpoints which were slightly delayed in development were the caudal neural tube, branchial bars, forelimb and hindlimb. The only effect on the embryos that could not be explained as a transient delay in development induced by heat was the induction of unsegmented somites. Additional embryos were exposed to 42 degrees C for 15-20 min in vitro and examined specifically for unsegmented somites, which were observed in 47% of embryos exposed to 42 degrees C in vivo or in vitro. This phenomenon was observed in somites 9-20, i.e., those that give rise to cervical and thoracic vertebrae and ribs. These results correlated well with the axial skeletal malformations observed in PND 3 pups exposed to the same heat treatment (C.A. Kimmel et al., '93). PMID:8248863
Cuff, J M; Kimmel, G L; Kimmel, C A; Heredia, D J; Tudor, N; Chen, J
Neuronal precursors are continuously integrated into the adult olfactory bulb (OB). The vast majority of these precursor cells originates from the subventricular zone and migrates along the rostral migratory stream (RMS) en route to the OB. This process, called postnatal neurogenesis, results from intricate pathways depending both on cell-autonomous factors and extrinsic regulation provided by the local environment. Using electroporation in postnatal mice to label neuronal precursors with green fluorescent protein (GFP) and to reduce the expression levels of doublecortin (DCX) with short-hairpin (Sh) RNA, we investigated the consequences of impairing migration on the fate of postnatal-formed neurons. First, we showed that electroporation of Dcx ShRNA plasmid efficiently knocks down the expression of DCX and disrupts cells migration along the RMS. Second, we found misplaced anomalous migrating cells that displayed defects in polarity and directionality. Third, patch-clamp recordings performed at 5-7 days post-electroporation (dpe) revealed increased density of voltage-dependent Na(+) channels and enhanced responsiveness to GABA(A) receptor agonist. At later time points (i.e., 12 and 30 dpe), most of the Dcx ShRNA(+) cells developed in the core of the OB and displayed aberrant dendritic length and branching. Additional analysis revealed the formation of GABAergic and glutamatergic synaptic inputs on the mispositioned neurons. Finally, quantifying fate determination by numbering the proportion of GFP(+)/calretinin(+) newborn neurons revealed that Dcx ShRNA(+) cells acquire mature phenotype despite their immature location. We conclude that altering the pace of migration at early stages of postnatal neurogenesis profoundly modifies the tightly orchestrated steps of neuronal maturation, and unveils the influence of microenvironment on controlling neuronal development in the postnatal forebrain. PMID:21593340
Belvindrah, Richard; Nissant, Antoine; Lledo, Pierre-Marie
After the completion of skin development, angiogenesis, i.e., the growth of new capillaries from pre-existing blood vessels, is held to occur in the skin only under pathologic conditions. It has long been noted, however, that hair follicle cycling is associated with prominent changes in skin perfusion, that the epithelial hair bulbs of anagen follicles display angiogenic properties, and that the
Lars Mecklenburg; Desmond J. Tobin; Sven Müller-Röver; Bori Handjiski; Gunnar Wendt; Eva M. J. Peters; Susanne Pohl; Ingrid Moll; Ralf Paus
The hair cycle consisting of growing and resting phases, is subject to widespread disease such as androgenic alopecia or loss of pigment which are in need of effective, targeted therapeutics. In order to develop a hair-follicle delivery system we demonstrate here that phosphatidylcholine liposomes entrapping either the fluorescent dye calcein or the pigment melanin can deliver these molecules into the
Lingna Li; Robert M. Hoffman
In our previous study, we reported on the development and preliminary testing of a prototype resonance electrical impedance spectroscopy (REIS) system with a pair of probes. Although our pilot study on 150 young women ranging from 30 to 50 years old indicated the feasibility of using REIS output sweep signals to classify between the women who had negative examinations and those who would ultimately be recommended for biopsy, the detection sensitivity was relatively low. To improve performance when using REIS technology, we recently developed a new multi-probe based REIS system. The system consists of a sensor module box that can be easily lifted along a vertical support device to fit women of different height. Two user selectable breast placement "cups" with different curvatures are included in the system. Seven probes are mounted on each of the cups on opposing sides of the sensor box. By rotating the sensor box, the technologist can select the detection sensor cup that better fits the breast size of the woman being examined. One probe is mounted in the cup center for direct contact with the nipple and the other six probes are uniformly distributed along an outside circle to enable contact with six points on the outer and inner breast skin surfaces. The outer probes are located at a distance of 60mm away from the center (nipple) probe. The system automatically monitors the quality of the contact between the breast surface and each of the seven probes and data acquisition can only be initiated when adequate contact is confirmed. The measurement time for each breast is approximately 15 seconds during which time the system records 121 REIS signal sweep outputs generated from 200 KHz to 800 KHz at 5 KHz increments for all preselected probe pairs. Currently we are measuring 6 pairs between the center probe and each of six probes located on the outer circle as well as two pairs between probe pairs on the outer circle. This new REIS system has been installed in our clinical breast imaging facility. We are conducting a prospective study to assess performance when using this REIS system under an approved IRB protocol. Over 200 examinations have been conducted to date. Our experience showed that this new REIS system was easy to operate and the REIS examination was fast and considered "comfortable" by examinees since the women presses her breast into the cup herself without any need for forced breast compression, and all but a few highly sensitive women have any sensation of an electrical current during the measurement.
Gur, David; Zheng, Bin; Dhurjaty, Sreeram; Wolfe, Gene; Fradin, Mary; Weil, Richard; Sumkin, Jules; Zuley, Margarita
\\u000a Laser and IPL treatments for hair removal depend on the presence of melanin in the hair shaft. The ideal patient for laser\\u000a hair removal has light skin with black, coarse hair. There is substantial evidence for laser and photoepilation with a total\\u000a of 43 identified controlled trials in the beginning of 2009. Laser treatment and photoepilation are superior to conventional
Annesofie Faurschou; Merete Haedersdal
The ATPases associated with various cellular activities (AAA) proteins are widespread in living organisms. Some of the AAA-type ATPases possess metalloprotease activities. Other members constitute the 26S proteasome complexes. In recent years, a few AAA members have been implicated in vesicle-mediated secretion, membrane fusion, cellular organelle biogenesis, and hypersensitive responses (HR) in plants. However, the physiological roles and biochemical activities of plant AAA proteins have not yet been defined at the molecular level, and regulatory mechanisms underlying their functions are largely unknown. In this study, we showed that overexpression of an Arabidopsis gene encoding a mitochondrial AAA protein, ATPase-in-Seed-Development (ASD), induces morphological and anatomical defects in seed maturation. The ASD gene is expressed at a high level during the seed maturation process and in mature seeds but is repressed rapidly in germinating seeds. Transgenic plants overexpressing the ASD gene are morphologically normal. However, seed formation is severely disrupted in the transgenic plants. The ASD gene is induced by abiotic stresses, such as low temperatures and high salinity, in an abscisic acid (ABA)- dependent manner. The ASD protein possesses ATPase activity and is localized into the mitochondria. Our observations suggest that ASD may play a role in seed maturation by influencing mitochondrial function under abiotic stress.
Baek, Kon; Seo, Pil Joon; Park, Chung-Mo
There is growing evidence that metabolic alterations play an important role in cancer development and progression. The metabolism of cancer cells is reprogrammed in order to support their rapid proliferation. Elevated fatty acid synthesis is one of the most important aberrations of cancer cell metabolism. An enhancement of fatty acids synthesis is required both for carcinogenesis and cancer cell survival, as inhibition of key lipogenic enzymes slows down the growth of tumor cells and impairs their survival. Based on the data that serum fatty acid synthase (FASN), also known as oncoantigen 519, is elevated in patients with certain types of cancer, its serum level was proposed as a marker of neoplasia. This review aims to demonstrate the changes in lipid metabolism and other metabolic processes associated with lipid metabolism in pancreatic ductal adenocarcinoma (PDAC), the most common pancreatic neoplasm, characterized by high mortality. We also addressed the influence of some oncogenic factors and tumor suppressors on pancreatic cancer cell metabolism. Additionally the review discusses the potential role of elevated lipid synthesis in diagnosis and treatment of pancreatic cancer. In particular, FASN is a viable candidate for indicator of pathologic state, marker of neoplasia, as well as, pharmacological treatment target in pancreatic cancer. Recent research showed that, in addition to lipogenesis, certain cancer cells can use fatty acids from circulation, derived from diet (chylomicrons), synthesized in liver, or released from adipose tissue for their growth. Thus, the interactions between de novo lipogenesis and uptake of fatty acids from circulation by PDAC cells require further investigation.
Swierczynski, Julian; Hebanowska, Areta; Sledzinski, Tomasz
Infantile spasms (ISS) are an epilepsy disorder frequently associated with severe developmental outcome and have diverse genetic etiologies. We ascertained 11 subjects with ISS and novel copy number variants (CNVs) and combined these with a new cohort with deletion 1p36 and ISS, and additional published patients with ISS and other chromosomal abnormalities. Using bioinformatics tools, we analyzed the gene content of these CNVs for enrichment in pathways of pathogenesis. Several important findings emerged. First, the gene content was enriched for the gene regulatory network involved in ventral forebrain development. Second, genes in pathways of synaptic function were overrepresented, significantly those involved in synaptic vesicle transport. Evidence also suggested roles for GABAergic synapses and the postsynaptic density. Third, we confirm the association of ISS with duplication of 14q12 and maternally inherited duplication of 15q11q13, and report the association with duplication of 21q21. We also present a patient with ISS and deletion 7q11.3 not involving MAGI2. Finally, we provide evidence that ISS in deletion 1p36 may be associated with deletion of KLHL17 and expand the epilepsy phenotype in that syndrome to include early infantile epileptic encephalopathy. Several of the identified pathways share functional links, and abnormalities of forebrain synaptic growth and function may form a common biologic mechanism underlying both ISS and autism. This study demonstrates a novel approach to the study of gene content in subjects with ISS and copy number variation, and contributes further evidence to support specific pathways of pathogenesis.
Paciorkowski, Alex R; Thio, Liu Lin; Rosenfeld, Jill A; Gajecka, Marzena; Gurnett, Christina A; Kulkarni, Shashikant; Chung, Wendy K; Marsh, Eric D; Gentile, Mattia; Reggin, James D; Wheless, James W; Balasubramanian, Sandhya; Kumar, Ravinesh; Christian, Susan L; Marini, Carla; Guerrini, Renzo; Maltsev, Natalia; Shaffer, Lisa G; Dobyns, William B
Infantile spasms (ISS) are an epilepsy disorder frequently associated with severe developmental outcome and have diverse genetic etiologies. We ascertained 11 subjects with ISS and novel copy number variants (CNVs) and combined these with a new cohort with deletion 1p36 and ISS, and additional published patients with ISS and other chromosomal abnormalities. Using bioinformatics tools, we analyzed the gene content of these CNVs for enrichment in pathways of pathogenesis. Several important findings emerged. First, the gene content was enriched for the gene regulatory network involved in ventral forebrain development. Second, genes in pathways of synaptic function were overrepresented, significantly those involved in synaptic vesicle transport. Evidence also suggested roles for GABAergic synapses and the postsynaptic density. Third, we confirm the association of ISS with duplication of 14q12 and maternally inherited duplication of 15q11q13, and report the association with duplication of 21q21. We also present a patient with ISS and deletion 7q11.3 not involving MAGI2. Finally, we provide evidence that ISS in deletion 1p36 may be associated with deletion of KLHL17 and expand the epilepsy phenotype in that syndrome to include early infantile epileptic encephalopathy. Several of the identified pathways share functional links, and abnormalities of forebrain synaptic growth and function may form a common biologic mechanism underlying both ISS and autism. This study demonstrates a novel approach to the study of gene content in subjects with ISS and copy number variation, and contributes further evidence to support specific pathways of pathogenesis. PMID:21694734
Paciorkowski, Alex R; Thio, Liu Lin; Rosenfeld, Jill A; Gajecka, Marzena; Gurnett, Christina A; Kulkarni, Shashikant; Chung, Wendy K; Marsh, Eric D; Gentile, Mattia; Reggin, James D; Wheless, James W; Balasubramanian, Sandhya; Kumar, Ravinesh; Christian, Susan L; Marini, Carla; Guerrini, Renzo; Maltsev, Natalia; Shaffer, Lisa G; Dobyns, William B
Suggests a simple technique for collecting and observing human hair roots to compare structure, function, and variation. Students extract their own hair samples and view them using a 40-power microscope objective. Differences between active/inactive phases of hair growth are readily observed. (The activity can be adapted for younger students.) (DH)
Jones, Helen J.
Hair loss is a very common and distressing problem faced by family physicians, in day to day practice. With a good history and physical examination most of the common causes of hair loss can be diagnosed. Androgenic alopecia is the commonest cause of hair loss in males and Telogen Effluvium in females. Other causes include Alopecia areata. Scarring alopecia needs
Sandeep Rai; Madhur Rai; Shiv Kumar
Cleft palate represents one of the most common congenital birth defects in humans. TGF? signaling, which is mediated by Smad-dependent and Smad-independent pathways, plays a crucial role in regulating craniofacial development and patterning, particularly in palate development. However, it remains largely unknown whether the Smad-independent pathway contributes to TGF? signaling function during palatogenesis. In this study, we investigated the function of TGF? activated kinase 1 (Tak1), a key regulator of Smad-independent TGF? signaling in palate development. We show that Tak1 protein is expressed in both the epithelium and mesenchyme of the developing palatal shelves. Whereas deletion of Tak1 in the palatal epithelium or mesenchyme did not give rise to a cleft palate defect, inactivation of Tak1 in the neural crest lineage using the Wnt1-Cre transgenic allele resulted in failed palate elevation and subsequently the cleft palate formation. The failure in palate elevation in Wnt1-Cre;Tak1F/F mice results from a malformed tongue and micrognathia, resembling human Pierre Robin sequence cleft of the secondary palate. We found that the abnormal tongue development is associated with Fgf10 overexpression in the neural crest-derived tongue tissue. The failed palate elevation and cleft palate were recapitulated in an Fgf10-overexpressing mouse model. The repressive effect of the Tak1-mediated noncanonical TGF? signaling on Fgf10 expression was further confirmed by inhibition of p38, a downstream kinase of Tak1, in the primary cell culture of developing tongue. Tak1 thus functions to regulate tongue development by controlling Fgf10 expression and could represent a candidate gene for mutation in human PRS clefting.
Song, Zhongchen; Liu, Chao; Iwata, Junichi; Gu, Shuping; Suzuki, Akiko; Sun, Cheng; He, Wei; Shu, Rong; Li, Lu; Chai, Yang; Chen, YiPing
Cleft palate represents one of the most common congenital birth defects in humans. TGF? signaling, which is mediated by Smad-dependent and Smad-independent pathways, plays a crucial role in regulating craniofacial development and patterning, particularly in palate development. However, it remains largely unknown whether the Smad-independent pathway contributes to TGF? signaling function during palatogenesis. In this study, we investigated the function of TGF? activated kinase 1 (Tak1), a key regulator of Smad-independent TGF? signaling in palate development. We show that Tak1 protein is expressed in both the epithelium and mesenchyme of the developing palatal shelves. Whereas deletion of Tak1 in the palatal epithelium or mesenchyme did not give rise to a cleft palate defect, inactivation of Tak1 in the neural crest lineage using the Wnt1-Cre transgenic allele resulted in failed palate elevation and subsequently the cleft palate formation. The failure in palate elevation in Wnt1-Cre;Tak1(F/F) mice results from a malformed tongue and micrognathia, resembling human Pierre Robin sequence cleft of the secondary palate. We found that the abnormal tongue development is associated with Fgf10 overexpression in the neural crest-derived tongue tissue. The failed palate elevation and cleft palate were recapitulated in an Fgf10-overexpressing mouse model. The repressive effect of the Tak1-mediated noncanonical TGF? signaling on Fgf10 expression was further confirmed by inhibition of p38, a downstream kinase of Tak1, in the primary cell culture of developing tongue. Tak1 thus functions to regulate tongue development by controlling Fgf10 expression and could represent a candidate gene for mutation in human PRS clefting. PMID:23460641
Song, Zhongchen; Liu, Chao; Iwata, Junichi; Gu, Shuping; Suzuki, Akiko; Sun, Cheng; He, Wei; Shu, Rong; Li, Lu; Chai, Yang; Chen, YiPing
BACKGROUND: Childhood obesity is on the rise and is a major risk factor for type 2 diabetes later in life. Recent evidence indicates that abnormalities that increase risk for diabetes may be initiated early in infancy. Since the offspring of women with diabetes have an increased long-term risk for obesity and type 2 diabetes, the impact of maternal metabolic abnormalities
Sylvia H Ley; Deborah L O'Connor; Ravi Retnakaran; Jill K Hamilton; Mathew Sermer; Bernard Zinman; Anthony J Hanley
Huanglongbing (HLB) causes considerable economic losses to citrus industries worldwide. Its management depends on controlling of the Asian citrus Psyllid (ACP), the vector of the bacterium, Candidatus Liberibacter asiaticus (CLas), the causal agent of HLB. Silencing genes by RNA interference (RNAi) is a promising tool to explore gene functions as well as control pests. In the current study, abnormal wing disc (awd) gene associated with wing development in insects is used to interfere with the flight of psyllids. Our study showed that transcription of awd is development-dependent and the highest level was found in the last instar (5(th)) of the nymphal stage. Micro-application (topical application) of dsRNA to 5(th) instar of nymphs caused significant nymphal mortality and adult wing-malformation. These adverse effects in ACP were positively correlated with the amounts of dsRNA used. A qRT-PCR analysis confirmed the dsRNA-mediated transcriptional down-regulation of the awd gene. Significant down-regulation was required to induce a wing-malformed phenotype. No effect was found when dsRNA-gfp was used, indicating the specific effect of dsRNA-awd. Our findings suggest a role for awd in ACP wing development and metamorphosis. awd could serve as a potential target for insect management either via direct application of dsRNA or by producing transgenic plants expressing dsRNA-awd. These strategies will help to mitigate HLB by controlling ACP. PMID:23734251
El-Shesheny, Ibrahim; Hajeri, Subhas; El-Hawary, Ibrahim; Gowda, Siddarame; Killiny, Nabil
The American serpentine leafminer fly, Liriomyza trifolii (Burgess), is one of the most destructive polyphagous pests worldwide. In this study, we determined electron beam doses for inhibition of normal development of the leaf miner and investigated the effect of electron beam irradiation on DNA damage and p53 stability. Eggs (0-24 h old), larvae (2nd instar), puparia (0-24 h old after pupariation) and adults (24 h after emergence) were irradiated with increasing doses of electron beam irradiation (six levels between 30 and 200 Gy). At 150 Gy, the number of adults that developed from irradiated eggs, larvae and puparia was lower than in the untreated control. Fecundity and egg hatchability decreased depending on the doses applied. Reciprocal crosses between irradiated and unirradiated flies demonstrated that males were more radiotolerant than females. Adult longevity was not affected in all stages. The levels of DNA damage in L. trifolii adults were evaluated using the alkaline comet assay. Our results indicate that electron beam irradiation increased levels of DNA damage in a dose-dependent manner. Moreover, low doses of electron beam irradiation led to the rapid appearance of p53 protein within 6 h; however, it decreased after exposure to high doses (150 Gy and 200 Gy). These results suggest that electron beam irradiation induced not only abnormal development and reproduction but also p53 stability caused by DNA damage in L. trifolii. We conclude that a minimum dose of 150 Gy should be sufficient for female sterilization of L. trifolii.
Koo, Hyun-Na; Yun, Seung-Hwan; Yoon, Changmann; Kim, Gil-Hah
Huanglongbing (HLB) causes considerable economic losses to citrus industries worldwide. Its management depends on controlling of the Asian citrus Psyllid (ACP), the vector of the bacterium, Candidatus Liberibacter asiaticus (CLas), the causal agent of HLB. Silencing genes by RNA interference (RNAi) is a promising tool to explore gene functions as well as control pests. In the current study, abnormal wing disc (awd) gene associated with wing development in insects is used to interfere with the flight of psyllids. Our study showed that transcription of awd is development-dependent and the highest level was found in the last instar (5th) of the nymphal stage. Micro-application (topical application) of dsRNA to 5th instar of nymphs caused significant nymphal mortality and adult wing-malformation. These adverse effects in ACP were positively correlated with the amounts of dsRNA used. A qRT-PCR analysis confirmed the dsRNA-mediated transcriptional down-regulation of the awd gene. Significant down-regulation was required to induce a wing-malformed phenotype. No effect was found when dsRNA-gfp was used, indicating the specific effect of dsRNA-awd. Our findings suggest a role for awd in ACP wing development and metamorphosis. awd could serve as a potential target for insect management either via direct application of dsRNA or by producing transgenic plants expressing dsRNA-awd. These strategies will help to mitigate HLB by controlling ACP.
El-Hawary, Ibrahim; Gowda, Siddarame; Killiny, Nabil
SUMMARY In adult skin, epithelial hair follicle stem cells (SCs) reside in a quiescent niche and are essential for cyclic bouts of hair growth. Niche architecture becomes pronounced postnatally at the start of the first hair cycle. Whether SCs exist or function earlier isunknown.Here we show that slow-cyclingcells ap- pear early in skin development, express SC markers, and later give
Jonathan A. Nowak; Lisa Polak; H. Amalia Pasolli; Elaine Fuchs
The relation between hair growth and levels of sex hormones in serum and saliva was investigated in 256 !Kung San and Kavango men (ages 18 to 39 years) from Namibia/Southern Africa. Serum concentrations of total testosterone (Tser), 5 alpha-dihydrotestosterone (DHT), and estradiol (E2) as well as the level of bioavailable non-SHBG-bound testosterone in the saliva (Tsal) were determined by radioimmunoassay. The distribution and density of scalp and facial hair as well as the development of terminal hair on the chest, abdomen, pubic area, arms, fingers, and legs were categorized using objective criteria. Covariance analyses revealed marked differences in the distribution of body hair in the San and the Negro sample. This is partly explained by a significant influence of androgen and estrogen levels on the growth of terminal hair. DHT and the ratio DHT/Tser are significantly positively related to midphalangeal hair growth and negatively to pubic hair development. Tsal, the bioavailable fraction of total testosterone, exerts a weak positive influence on the degree of arm and leg hair growth; the most significant positive effect on the growth of abdominal, arm, and leg hair in our samples is caused by E2. The ratio Tser/E2 correlates significantly negatively with the arm and leg hair development and the ratio DHT/E2 with the degree of abdominal, pubic, arm, and leg hair, whereas lower DHT concentrations occur in men with stronger hair development. PMID:8273828
Winkler, E M; Christiansen, K
A new method for the isolation of root hairs from the model legume, Medicago truncatula, was developed. The procedure involves the propagation of detached roots on agar plates and the collection of root hairs by immersion in liquid nitrogen. Yields of up to 40 mg of root hair protein were obtained from 50-100 root tips grown for 3 weeks on
Javier Ramos; Ton Bisseling
This review focuses on basic aspects of method development and validation of hair testing procedures. Quality assurance is a major issue in drug testing in hair resulting in new recommendations, validation procedures and inter-laboratory comparisons. Furthermore recent trends in research concerning hair analysis are discussed, namely mechanisms of drug incorporation and retention, novel analytical procedures (especially ones using liquid chromatography–mass
Frank Musshoff; Burkhard Madea
Hair transplants were developed and championed by dermatologists. However, dermatology literature has few contributions from within our specialty. In this manuscript, we present our evaluation of a specific graft harvesting approach for hair transplants referred to as Follicular unit extraction (FUE). In particular, we sought to evaluate the rate of harvest attempts that did not produce an actual hair folliclular unit graft. PMID:24746303
Rashid, Rashid M
A new hair visual appearance measurement system called SAMBA from Bossa Nova Technologies (Venice, CA) has been employed to measure effects of cosmetic treatments on hair shine and surface smoothness of different types of hair samples. Experimental procedures for evaluations of shine value and surface cuticle angle of hair samples treated with rinse-off products (shampoo or/and conditioner) have been successfully established and applied. We demonstrated that hair spray and conditioner formulas containing PPG-3 benzyl ether myristate (PBEM) (1) showed great performance on shine enhancement for hairs with light and medium colors. Instrumental measurement of shine values was also conducted to compare different commercial shampoo and conditioner products. This study showed reliable utility of SAMBA system and demonstrated the shine enhancement of PBEM in hair care. PMID:19450419
Gao, Timothy; Pereira, Abel; Zhu, Sam
Haemoglobin (Hb) abnormalities though quite frequent, are generally detected in populations during surveys and programmes run for prevention of Hb disorders. Several methods are now available for detection of Hb abnormalities. In this review, the following are discussed: (i) the methods used for characterization of haemoglobin disorders; (ii) the problems linked to diagnosis of thalassaemic trait; (iii) the strategy for detection of common Hb variants; and (iv) the difficulties in identification of rare variants. The differences between developing and industrialized countries for the strategies employed in the diagnosis of abnormal haemoglobins are considered. We mention the limits and pitfalls for each approach and the necessity to characterize the abnormalities using at least two different methods. The recommended strategy is to use a combination of cation-exchange high performance chromatography (CE-HPLC), capillary electrophoresis (CE) and when possible isoelectric focusing (IEF). Difficult cases may demand further investigations requiring specialized protein and/or molecular biology techniques.
Wajcman, Henri; Moradkhani, Kamran
Earlier studies showed that dermal cells lose trichogenic capacity with passage, but studies on the effect of keratinocyte passage on human hair follicle neogenesis and graft quality have been hampered by the lack of a suitable model system. We recently documented human hair follicle neogenesis in grafted dermal-epidermal composites, and in the present study, we determined the effects of keratinocyte passage on hair follicle neogenesis. Dermal equivalents were made with cultured human dermal papilla cells and were overlaid with either primary or passaged human keratinocytes to form dermal-epidermal composites; these were then grafted onto immunodeficient mice. Superior hair follicle neogenesis was observed using early keratinocyte cultures. Characteristics such as formation of hair shafts and sebaceous glands, presence of hair follicles with features of anagen or telogen follicles, and reproducible hair and skin function parameters make this model a tool to study human hair follicle neogenesis and development. PMID:24758480
Thangapazham, Rajesh L; Klover, Peter; Li, Shaowei; Wang, Ji-An; Sperling, Leonard; Darling, Thomas N
Female pattern hair loss (FPHL) is a common hair disorder of the central scalp. The clinical change in hair density, related to a change in the hair cycle and miniaturization of the hair follicle, is generally considered to be potentially reversible. However, there is now evidence of a permanent hair loss that develops in a subset of women with FPHL. The presence of a perifollicular lymphohistiocytic infiltrate and fibrosis is seen without follicular drop-out in biopsies of women with FPHL and with a notable follicular drop-out in a cicatricial form of this condition (heretofore called cicatricial pattern hair loss) as well as in fibrosing alopecia in a pattern distribution, currently classified as a subset of lichen planopilaris. The potential relationship of these conditions as well as frontal fibrosing alopecia and central centrifugal cicatricial alopecia, two other conditions of permanent hair loss seen primary in women, is discussed. PMID:16382668
Olsen, Elise A
The polycystic kidney disease-1 (Pkd1) gene encodes a large transmembrane protein (polycystin-1 or PC-1) that is reported to function as a fluid flow-sensor in the kidney. As a member of the transient receptor potential family, PC-1 has also been hypothesized to play a role in the elusive mechanoelectrical transduction (MET) channel in inner ear hair cells. Here, we analyzed two independent mouse models of PC-1, a knockin (KI) mutant line and a hair cell specific inducible Cre mediated knockout line. Both models exhibit normal MET channel function at neonatal ages despite hearing loss and ultra-structural abnormalities of stereocilia that remain properly polarized at adult ages. These findings demonstrate that PC-1 plays an essential role in stereocilia structure and maintenance but not directly in MET channel function or planar cell polarity. We also demonstrate that PC-1 is co-localized with F-actin in hair cell stereocilia in vivo, using a haemagglutinin (HA)-tagged PC-1KI mouse model, and in renal epithelial cell microvilli in vitro. These results not only demonstrate a novel role for PC-1 in the cochlea, but also suggest insight into the development of polycystic kidney disease.
Steigelman, Katherine A.; Lelli, Andrea; Wu, XuDong; Gao, Jiangang; Lin, Susan; Piontek, Klaus; Wodarczyk, Claas; Boletta, Alessandra; Kim, Hyunko; Qian, Feng; Germino, Gregory; Geleoc, Gwenaelle S.G.; Holt, Jeffrey R.; Zuo, Jian
The polycystic kidney disease-1 (Pkd1) gene encodes a large transmembrane protein (polycystin-1, or PC-1) that is reported to function as a fluid flow sensor in the kidney. As a member of the transient receptor potential family, PC-1 has also been hypothesized to play a role in the elusive mechanoelectrical transduction (MET) channel in inner ear hair cells. Here, we analyze two independent mouse models of PC-1, a knock-in (KI) mutant line and a hair cell-specific inducible Cre-mediated knock-out line. Both models exhibit normal MET channel function at neonatal ages despite hearing loss and ultrastructural abnormalities of sterecilia that remain properly polarized at adult ages. These findings demonstrate that PC-1 plays an essential role in stereocilia structure and maintenance but not directly in MET channel function or planar cell polarity. We also demonstrate that PC-1 is colocalized with F-actin in hair cell stereocilia in vivo, using a hemagglutinin-tagged PC-1 KI mouse model, and in renal epithelial cell microvilli in vitro. These results not only demonstrate a novel role for PC-1 in the cochlea, but also suggest insight into the development of polycystic kidney disease. PMID:21865467
Steigelman, Katherine A; Lelli, Andrea; Wu, Xudong; Gao, Jiangang; Lin, Susan; Piontek, Klaus; Wodarczyk, Claas; Boletta, Alessandra; Kim, Hyunho; Qian, Feng; Germino, Gregory; Géléoc, Gwenaëlle S G; Holt, Jeffrey R; Zuo, Jian
The expert working group 'Hair Care Products' of the DGK currently conducts a wide study to contribute to the understanding of how single hair fibre and hair collective properties contribute towards hair 'handle' and 'feel'. During the first stage of this study four hair types were selected from a large group of individual European hair braids, according to either similar or widely different panel ratings for handle. Against the background of the panel test and the state of the literature the working group readily identified the bending properties of single fibres interacting in the tress as a fibre collective and fibre friction as being of central relevance for hair 'handle' and 'feel'. Fibre diameters of the hair types were determined by Optical Fibre Diameter Analyzer and by weighing. From these data mean ellipticity and bending stiffness distributions were calculated. Single fibre friction was determined by the capstan method in the root, middle and tip regions. Significant differences were determined between the hair types in diameters, ellipticity, bending stiffness and friction. The results lead to conclude that 'handle' is perceived as inferior when the hair is thick and bending stiffness thus high. For such hair differences in handle rating are related to differences in friction, namely in the tip region. For thin and thus 'soft' hair fibre friction seems to play only a minor role. PMID:18492202
Wortmann, F-J; Schwan-Jonczyk, A
Confocal microscopy is an excellent method for studying the localization of fluorescent stains. Used in this way, superior 3D images can be obtained from multiple optical sections with very shallow depth of field. The main advantage of this technique is that the sample is not damaged. We have taken serial confocal sections of hair and via specific image enhancement routines
J. M. Lagarde; P. Peyre; D. Redoules; D. Black; M. Briot; Y. Gall
In a review of the relationship of hair loss to oral contraceptive (OC) use, several studies are examined. The effect of pregnancy on hair loss has been substantiated. After the 3rd month of pregnancy the proportion of follicles in active growth rises. Increased shedding follows childbirth due to the delayed physiological passage of some follicles into the resting phase, blood loss, and sometimes anticoagulants. In contraceptive studies it can be shown that in 1/2 of the patients there was a temporary increase in the proportion of resting during early treatment but that pretreatment status was regained in 6 months. In 11 patients in this study who showed high pretreatment levels of resting follicles, the proportion of actively growing follicles actually increased with OCs. The incidence of diffuse alopecia in women between 1952 and 1971 has remained unchanged although OC use has increased. This suggests the effect of OCs on alopecia is insignificant. There may be a causal relationship between stopping estrogen and hair loss. However, it may be possible that genetically suseptible women might be affected by OCs. In patients where hair loss is accompanied by seborrhea or where there is hirsuitism it is suggested that the pill be discontinued. PMID:4736624
This class activity is designed to introduce young learners to the concept of tree diagrams. This class activity requires learners to organize data about the individual student's physical characteristics(gender, hair and eye color) utilizing connecting cubes. The activity includes a follow up activity, questions, tips on getting started, a teacher resource page, and a printable version of the problem.
Hair loss is commonly seen in autoimmune diseases. In pemphigus, although scalp involvement is common, hair loss is rarely reported. In classical bullous pemphigoid, alopecia is not reported while it is described in the Brusting-Perry variant of bullous pemphigoid and in epidermolysis bullosa acquisita. In these two diseases alopecia is cicatricial. In connective tissue diseases, in lupus erythematosus (LE) hair loss is frequent; in particular in LE there are two types of alopecia: non scarring and scarring alopecia. The non scarring form is a finding of acute systemic LE and the scarring form develops when a typical discoid lesion is located on the scalp. In dermatomyositis alopecia is usually non scarring and generalized. In scleroderma, alopecia is associated with en coupe de sabre morphea. PMID:24566567
Parodi, A; Cozzani, E
A person’s skin pigment, which determines hair color and skin tone, is influenced by the melanocortin-1 (MC1R) gene receptor. For the population’s 1 to 2 percent of redheads, a mutation in MC1R accounts for their red hair color and typical light skin. Now researchers from Harvard Medical School (a component of the Dana-Farber Cancer Institute) have discovered that the same MC1R mutation responsible for the red-hair phenotype also promotes an important cancer-causing pathway. The new findings, reported online August 22 in the journal Molecular Cell, help to explain the molecular mechanisms that underlie redheads’ well-known risk of developing melanoma, providing new insights for treating and preventing this dangerous type of skin cancer.
Congenital Horner syndrome is a rare disorder that accounts for less than 5% of all cases of Horner syndrome. Like Horner syndrome in general, it consists primarily of ptosis, miosis, and anhidrosis. Congenital Horner syndrome may manifest some special features such as iris heterochromia since the sympathetic nervous system is an essential component for the development and maintenance of eye color. We present 3 cases of unilateral straight hair in association with congenital Horner syndrome in which the patients had straight hair ipsilateral to the Horner syndrome, whereas on the contralateral side, it was curly, and we discuss possible mechanisms for this phenomenon. PMID:22622362
Wang, Frederick M; Wertenbaker, Christian; Cho, Hyung; Marmor, Maury A; Ahn-Lee, Sandra S; Bernard, Bruno A
The authors developed and qualified an automated routine screening tool to quantify hair shine. This tool is able to separately record individual properties of hair shine such as specular reflection and multiple reflection, as well as additional features such as sparkle, parallelism of hair fibers, and hair color, which strongly affect the subjective ranking by individual readers. A side-by-side comparison of different hair care and styling products with regard to hair shine using the automated screening tool in parallel with standard panel assessment showed that the automated system provides an almost identical ranking and the same statistical significances as the panel assessment. Provided stringent stratification of hair fibers for color and parallelism, the automated tool competes favorably with panel assessments of hair shine. In this case, data generated with the opsira Shine-Box are clearly superior over data generated by panel assessment in terms of reliability and repeatability, workload and time consumption, and sensitivity and specificity to detect differences after shampoo, conditioner, and leave-in treatment. The automated tool is therefore well suited to replace standard panel assessments in claim support, at least as a screening tool. A further advantage of the automated system over panel assessments is the fact that absolute numeric values are generated for a given hair care product, whereas panel assessments can only give rankings of a series of hair care products included in the same study. Thus, the absolute numeric data generated with the automated system allow comparison of hair care products between studies or at different time points after treatment. PMID:22152491
Hagens, Ralf; Wiersbinski, Tim; Becker, Michael E; Weisshaar, Jürgen; Schreiner, Volker; Wenck, Horst
The V-shaped hair bundles atop auditory hair cells and their uniform orientation are manifestations of epithelial planar cell polarity (PCP) required for proper perception of sound. PCP is regulated at the tissue level by a conserved core Wnt/PCP pathway. However, the hair cell-intrinsic polarity machinery is poorly understood. Recent findings implicate hair cell microtubules in planar polarization of hair cells. To elucidate the microtubule-mediated polarity pathway, we analyzed Lis1 function in the auditory sensory epithelium in the mouse. We show that conditional deletion of Lis1 in developing hair cells causes defects in cytoplasmic dynein and microtubule organization, resulting in planar polarity defects without overt effects on the core PCP pathway. Lis1 ablation during embryonic development results in defects in hair bundle morphology and orientation, cellular organization and junctional nectin localization. We present evidence that Lis1 regulates localized Rac-PAK signaling in embryonic hair cells, probably through microtubule-associated Tiam1, a guanine nucleotide exchange factor for Rac. Lis1 ablation in postnatal hair cells significantly disrupts centrosome anchoring and the normal V-shape of hair bundles, accompanied by defects in the pericentriolar matrix and microtubule organization. Lis1 is also required for proper positioning of the Golgi complex and mitochondria as well as for hair cell survival. Together, our results demonstrate that Lis1 mediates the planar polarity of hair cells through regulation of microtubule organization downstream of the tissue polarity pathway.
Sipe, Conor W.; Liu, Lixia; Lee, Jianyi; Grimsley-Myers, Cynthia; Lu, Xiaowei
The V-shaped hair bundles atop auditory hair cells and their uniform orientation are manifestations of epithelial planar cell polarity (PCP) required for proper perception of sound. PCP is regulated at the tissue level by a conserved core Wnt/PCP pathway. However, the hair cell-intrinsic polarity machinery is poorly understood. Recent findings implicate hair cell microtubules in planar polarization of hair cells. To elucidate the microtubule-mediated polarity pathway, we analyzed Lis1 function in the auditory sensory epithelium in the mouse. We show that conditional deletion of Lis1 in developing hair cells causes defects in cytoplasmic dynein and microtubule organization, resulting in planar polarity defects without overt effects on the core PCP pathway. Lis1 ablation during embryonic development results in defects in hair bundle morphology and orientation, cellular organization and junctional nectin localization. We present evidence that Lis1 regulates localized Rac-PAK signaling in embryonic hair cells, probably through microtubule-associated Tiam1, a guanine nucleotide exchange factor for Rac. Lis1 ablation in postnatal hair cells significantly disrupts centrosome anchoring and the normal V-shape of hair bundles, accompanied by defects in the pericentriolar matrix and microtubule organization. Lis1 is also required for proper positioning of the Golgi complex and mitochondria as well as for hair cell survival. Together, our results demonstrate that Lis1 mediates the planar polarity of hair cells through regulation of microtubule organization downstream of the tissue polarity pathway. PMID:23533177
Sipe, Conor W; Liu, Lixia; Lee, Jianyi; Grimsley-Myers, Cynthia; Lu, Xiaowei
The root hair development is controlled by diverse factors such as fate-determining developmental cues, auxin-related environmental factors, and hormones. In particular, the soil environmental factors are important as they maximize their absorption by modulating root hair development. These environmental factors affect the root hair developmental process by making use of diverse hormones. These hormonal factors interact with each other to modulate root hair development in which auxin appears to form the most intensive networks with the pathways from environmental factors and hormones. Moreover, auxin action for root hair development is genetically located immediately upstream of the root hair-morphogenetic genes. These observations suggest that auxin plays as an organizing node for environmental/hormonal pathways to modulate root hair growth.
Lee, Richard D.-W.; Cho, Hyung-Taeg
The root hair development is controlled by diverse factors such as fate-determining developmental cues, auxin-related environmental factors, and hormones. In particular, the soil environmental factors are important as they maximize their absorption by modulating root hair development. These environmental factors affect the root hair developmental process by making use of diverse hormones. These hormonal factors interact with each other to modulate root hair development in which auxin appears to form the most intensive networks with the pathways from environmental factors and hormones. Moreover, auxin action for root hair development is genetically located immediately upstream of the root hair-morphogenetic genes. These observations suggest that auxin plays as an organizing node for environmental/hormonal pathways to modulate root hair growth. PMID:24273547
Lee, Richard D-W; Cho, Hyung-Taeg
The existence of a growth and regeneration cycle makes the hair follicle a true paradigm of tissue homeostasis. Analysis of about 9000 cycles led us to propose a stochastic model of human hair dynamics. The existence of hair cycles implies that stem cells must be cyclically activated and hair melanin unit has to be renewed. Using different markers, we were able to identify two distinct epithelial stem cell reservoirs, located in the upper and lower thirds of the anagen hair follicle outer root sheath. These two reservoirs fuse during the regression phase and individualize again in the new forming anagen hair follicle. Using a set of antibodies specific of melanocyte lineage and melanogenesis, pigmentation unit turnover was followed throughout the entire hair cycle. In the terminal anagen hair, active melanocytes were localized on top of the dermal papilla, while amelanotic melanocytes were identified in the upper third of the outer root sheath (ORS). Those amelanotic melanocytes located in upper ORS probably represented a melanocyte reservoir for successive hair generation, since at the induction of anagen phase, some melanocytes were committed to cell division and melanogenesis was turned on, but only in the nascent hair bulb, close to the dermal papilla. PMID:12868268
Bernard, Bruno A
A profound knowledge of specific genetically determined anomalies of the hair may be of considerable value in the diagnosis of genetic syndromes. We give a review of a few recent developments in the field of genetic hair diseases. For example, the brittle hair due to sulphur deficiency (trichothiodystrophy) is nowadays regarded as genetically heterogeneous; three different syndromes can be distinguished: BIDS syndrome, Tay syndrome, and PIBIDS syndrome. Polarization microscopy revealed a striking resemblance of the hair anomalies found in trichothiodystrophy syndromes and those in acrodermatitis enteropathica. This surprising result indicates similar pathophysiological mechanisms. The Comèl-Netherton syndrome--long regarded as representing two different diseases--has recently been recognized as a clinically variable, but genetically homogeneous syndrome, which is most likely based on a single mutation ("lumping"). Minor's sweat test allows the recognition of women heterozygous for X-linked hypohidrotic ectodermal dysplasia and may help to appreciate seemingly non-specific hair findings, such as diffuse alopecia. PMID:2087835
Traupe, H; Hamm, H
Hair color differences are among the most obvious examples of phenotypic variation in humans. Although genome-wide association studies (GWAS) have implicated multiple loci in human pigment variation, the causative base-pair changes are still largely unknown. Here we dissect a regulatory region of the KITLG gene (encoding KIT ligand) that is significantly associated with common blond hair color in northern Europeans. Functional tests demonstrate that the region contains a regulatory enhancer that drives expression in developing hair follicles. This enhancer contains a common SNP (rs12821256) that alters a binding site for the lymphoid enhancer-binding factor 1 (LEF1) transcription factor, reducing LEF1 responsiveness and enhancer activity in cultured human keratinocytes. Mice carrying ancestral or derived variants of the human KITLG enhancer exhibit significant differences in hair pigmentation, confirming that altered regulation of an essential growth factor contributes to the classic blond hair phenotype found in northern Europeans. PMID:24880339
Guenther, Catherine A; Tasic, Bosiljka; Luo, Liqun; Bedell, Mary A; Kingsley, David M
Human hair is a biological layered system composed of two major layers, the cortex and the cuticle. We show spectrally resolved ellipsometry measurements of the ellipsometric parameters ? and ? of single human hairs. The spectra reflect the layered nature of hair and the optical anisotropy of the hair’s structure. In addition, measurements on strands of human hair show a high reproducibility of the ellipsometric parameters for different hair fiber bundles from the same person. Based on the measurements, we develop a model of the dielectric function of hair that explains the spectra. This model includes the dielectric properties of the cuticle and cortex as well as their associated layer thicknesses. In addition, surface roughness effects modelled by a roughness layer with an complex refractive index given by an effective medium approach can have a significant effect on the measurements. We derive values for the parameters of the cuticle surface roughness layer of the thickness dACu= 273-360 nm and the air inclusion fA= 0.6 -5.7%.  accepted for publication in J. Biomed Opt., 2005
Schulz, Benjamin; Chan, D.; Ruebhausen, M.; Wessel, S.; Wepf, R.
The absence of well-validated biomarkers of manganese (Mn) exposure in children remains a major obstacle for studies of Mn toxicity. We developed a hair cleaning methodology to establish the utility of hair as an exposure biomarker for Mn and other metals (Pb, Cr, Cu), using ICP-MS, scanning electron microscopy, and laser ablation ICP-MS to evaluate cleaning efficacy. Exogenous metal contamination on hair that was untreated or intentionally contaminated with dust or Mn-contaminated water was effectively removed using a cleaning method of 0.5% Triton X-100 sonication plus 1N nitric acid sonication. This cleaning method was then used on hair samples from children (n=121) in an ongoing study of environmental Mn exposure and related health effects. Mean hair Mn levels were 0.121 ?g/g (median = 0.073 ?g/g, range = 0.011 – 0.736 ?g/g), which are ~4 to 70-fold lower than levels reported in other pediatric Mn studies. Hair Mn levels were also significantly higher in children living in the vicinity of active, but not historic, ferroalloy plant emissions compared to controls (P<0.001). These data show that exogenous metal contamination on hair can be effectively cleaned of exogenous metal contamination, and they substantiate the use of hair Mn levels as a biomarker of environmental Mn exposure in children.
Eastman, Rachel R.; Jursa, Tom P.; Benedetti, Chiara; Lucchini, Roberto G.; Smith, Donald R.
We assessed whether the nuclear localization sequences (NLS) and C terminus of parathyroid hormone-related protein (PTHrP) play critical roles in brain development and function. We used histology, immunohistochemistry, histomorphometry, Western blots and electrophysiological recordings to compare the proliferation and differentiation of neural stem cells, neuronal hippocampal synaptic transmission, and brain phenotypes including shape and structures, in Pthrp knock-in mice, which express PTHrP (1–84), a truncated form of the protein that is missing the NLS and the C-terminal region of the protein, and their wild-type littermates. Results showed that Pthrp knock-in mice display abnormal brain shape and structures; decreased neural cell proliferative capacity and increased apoptosis associated with up-regulation of cyclin dependent kinase inhibitors p16, p21, p27 and p53 and down-regulation of the Bmi-1 oncogene; delayed neural cell differentiation; and impaired hippocampal synaptic transmission and plasticity. These findings provide in vivo experimental evidence that the NLS and C-terminus of PTHrP are essential not only for the regulation of neural cell proliferation and differentiation, but also for the maintenance of normal neuronal synaptic transmission and plasticity.
Gu, Zhen; Liu, Yahong; Zhang, Yongjie; Jin, Shulei; Chen, Qi; Goltzman, David; Karaplis, Andrew; Miao, Dengshun
In this study we generated RNA interference (RNAi)-mediated gene knockdown transgenic mice (transgenic RNAi mice) against the functional Inv gene. Inv mutant mice show consistently reversed internal organs (situs inversus), multiple renal cysts and neonatal lethality. The Inv::GFP-rescue mice, which introduced the Inv::GFP fusion gene, can rescue inv mutant mice phenotypes. This indicates that the Inv::GFP gene is functional in vivo. To analyze the physiological functions of the Inv gene, and to demonstrate the availability of transgenic RNAi mice, we introduced a short hairpin RNA expression vector against GFP mRNA into Inv::GFP-rescue mice and analyzed the gene silencing effects and Inv functions by examining phenotypes. Transgenic RNAi mice with the Inv::GFP-rescue gene (Inv-KD mice) down-regulated Inv::GFP fusion protein and showed hypomorphic phenotypes of inv mutant mice, such as renal cyst development, but not situs abnormalities or postnatal lethality. This indicates that shRNAi-mediated gene silencing systems that target the tag sequence of the fusion gene work properly in vivo, and suggests that a relatively high level of Inv protein is required for kidney development in contrast to left/right axis determination. Inv::GFP protein was significantly down-regulated in the germ cells of Inv-KD mice testis compared with somatic cells, suggesting the existence of a testicular germ cell-specific enhanced RNAi system that regulates germ cell development. The Inv-KD mouse is useful for studying Inv gene functions in adult tissue that are unable to be analyzed in inv mutant mice showing postnatal lethality. In addition, the shRNA-based gene silencing system against the tag sequence of the fusion gene can be utilized as a new technique to regulate gene expression in either in vitro or in vivo experiments.
Kamijho, Yuki; Shiozaki, Yayoi; Sakurai, Eiki; Hanaoka, Kazunori; Watanabe, Daisuke
Background Almost all land plants develop tip-growing filamentous cells at the interface between the plant and substrate (the soil). Root hairs form on the surface of roots of sporophytes (the multicellular diploid phase of the life cycle) in vascular plants. Rhizoids develop on the free-living gametophytes of vascular and non-vascular plants and on both gametophytes and sporophytes of the extinct rhyniophytes. Extant lycophytes (clubmosses and quillworts) and monilophytes (ferns and horsetails) develop both free-living gametophytes and free-living sporophytes. These gametophytes and sporophytes grow in close contact with the soil and develop rhizoids and root hairs, respectively. Scope Here we review the development and function of rhizoids and root hairs in extant groups of land plants. Root hairs are important for the uptake of nutrients with limited mobility in the soil such as phosphate. Rhizoids have a variety of functions including water transport and adhesion to surfaces in some mosses and liverworts. Conclusions A similar gene regulatory network controls the development of rhizoids in moss gametophytes and root hairs on the roots of vascular plant sporophytes. It is likely that this gene regulatory network first operated in the gametophyte of the earliest land plants. We propose that later it functioned in sporophytes as the diploid phase evolved a free-living habit and developed an interface with the soil. This transference of gene function from gametophyte to sporophyte could provide a mechanism that, at least in part, explains the increase in morphological diversity of sporophytes that occurred during the radiation of land plants in the Devonian Period.
Jones, Victor A.S.; Dolan, Liam