[Objective] The paper was to compare the infrared spectra of straight guard hairs of leopard cat and golden cat. [Method] The straight guard hairs of leopard cat and golden cat were detected and analyzed by FTIR （Fou...[Objective] The paper was to compare the infrared spectra of straight guard hairs of leopard cat and golden cat. [Method] The straight guard hairs of leopard cat and golden cat were detected and analyzed by FTIR （Fourier Transform Infrared Spectroscopy）. [Result] There was significant interspecific difference in the infrared spectra and second derivative spectra for the middle part of guard hair. An evident M-shaped bimodal absorption peak appeared in golden cat at 648 and 654 cm-1, respectively, while did not appear in leopard cat. The second derivative spec-tra of golden cat at wave numbers from 709 to 763 cm -1 were mainly unimodal peaks with strong peak intensity, while that of leopard cat mainly was M-shaped bi-modal absorption peak with weak peak intensity. It indicated that there was obvious difference in the structure of protein side chain in guard hairs of these two animals. [Conclusion] The FTIR analysis showed great application foreground in the study of animal hairs for interspecific identification.展开更多
The taxonomic status of long-tailed field mouse (Apodemus orestes) is still uncertain up to now.Some scholars regarded it as a subspecies or a synonym of dragon field mouse (A.draco),while other scholars considered it...The taxonomic status of long-tailed field mouse (Apodemus orestes) is still uncertain up to now.Some scholars regarded it as a subspecies or a synonym of dragon field mouse (A.draco),while other scholars considered it a valid species.In the study,five specimens of adult long-tailed field mouse,dragon field mouse and Chevrier's field mouse (A.chevrieri) (as a contrast) were chosen respectively.After treated,with the eyepiece micrometer in the inverted microscope,we made measurements of the widths of hairs and medullas and then calculated the medullary indexes of straight guard hairs from around the mouth,head,back,abdomen and forelimb of each species.The results indicate that,viewing at each of the five parts and the mixture of the five parts,there are no significant differences between A.orestes and A.draco,Significant differences can be found between A.orestes & A.chevrieri and A.draco & A.chevrieri though.The standpoint that A.orestes was listed as a valid species is not supported by this study.展开更多
In recent times,there had been reported cases of Pb poisoning in Anka gold mining area,Northwest Nigeria.Therefore,this study was carried out to determine the extent of bioaccumulation of heavy metals in the hairs and...In recent times,there had been reported cases of Pb poisoning in Anka gold mining area,Northwest Nigeria.Therefore,this study was carried out to determine the extent of bioaccumulation of heavy metals in the hairs and nails of children in the area.Forty samples(twenty nails and twenty hairs)samples were collected from ten boys and ten girls of ages 5–9 residing in the area.To ascertain the sources of heavy metals in children,15 soils samples,15 groundwater samples,5 samples of mine tailings,and 5 plants samples were collected.Hair and nails of the subjects were collected using internationally acceptable techniques.All samples were kept in uncontaminated ziplock bags prior to laboratory preparation and analysis.The samples were cleaned using nonionic detergent(triton X-100)and deionized water.The hairs and nails were digested with 10 mL of 6:1 mixture of nitric acid and perchloric acid.The soils,mine tailings,and plants were air-dried at room temperature,sieved,and chemically digested using the aqua regia method.The concentrations of metals in all the samples were determined using highperformance liquid chromatography–inductively coupled plasma–mass spectrometry.Statistical analysis was employed to unravel potential sources of metals in the media.Results showed that heavy metals in children of the area are above results from similar studies and pathological ranges for heavy metals in hairs and nails.Also,heavy metals in environmental media are above the recommended standards.Multivariate analysis showed that the metals are mainly from mining and other anthropogenic sources.Results of correlation between heavy metals in hairs and nails with those in geological samples revealed that heavy metal that bioaccumulates in the children of this area are mostly from contaminated environmental media.It is recommended that complete remediation and effective health education be carried out in the area.展开更多
In polymorphic mammalian species that display multiple color forms, those with dark, or melanic pelage would be prone to overheating, especially if they live in warm climates, because their fur absorbs solar energy at...In polymorphic mammalian species that display multiple color forms, those with dark, or melanic pelage would be prone to overheating, especially if they live in warm climates, because their fur absorbs solar energy at a higher rate. However, experimental studies indicate that certain physical properties of fur of dark individuals appear to prevent, or minimize heat stress, although it is not clear what properties do so. Here, we tested the possibility that black-furred individuals simply have shorter or thinner hair fibers, which would create a lighter （in terms of weight） coat or one that allows greater air flow for evaporative coo- ling. We examined museum specimens of eastern fox squirrels Sciurus niger, a species native to the United States and one that displays brown, grey or all-black pelage color, and used image analysis procedures to quantify hairs from the dorsal surface and tail. From examination of 43 specimens （19 brown, 9 black and 15 grey）, and 1,720 hairs, we found no significant difference in hair lengths across color morphs, but significant differences in hair fiber widths. Black squirrels had thinner body hairs than other forms （7% thinner）, but thicker tail hairs （9% thicker） than the others. Given that the dorsal surface would be directly exposed to solar radiation, we interpret this to be an adaptation to prevent heat stress during the day. The thicker tail hairs may be an adapta- tion for nighttime thermoregulation, since squirrels sleep with their tails wrapped around their bodies. These results add to a growing literature body of the functional significance of mammalian pelage [Current Zoology 57 （6）： 731-736, 2011].展开更多
The contents of total and methyl mercury in scalp hair samples of 1179 fishermenliving at a typical Hg-polluted region in Northeast China and 27 lying-in womenand their new born babies in Beijing have been determined ...The contents of total and methyl mercury in scalp hair samples of 1179 fishermenliving at a typical Hg-polluted region in Northeast China and 27 lying-in womenand their new born babies in Beijing have been determined by illstrumental neutronactivation analysis, gas chromatography (electron coupling) and other techniqlles.Only 18 of all fishermen have the Hg contents above 5 ig/g, which indicates that theHg pollution there has been substantially alleviated. The longitudinal Hg patternsof the lying-in women show a gradually lowering tendency during pregnant period.Further, the Hg contents of the new-born babies are generally above or close to those oftheir mothers, confirming the mechanism that the methyl Hg, an organic species of Hgwith high toxicity, is readily able to penetrate the placental barrier and accumulatedin fetus. Thus, the mercury poison hajs occurred at the early stage of pregnancy.展开更多
The presumed hairs of Holy Maria-Magdalena are studied here for mineral particles found on their surfaces, by the techniques of scanning electron microscopy coupled with energy dispersive X-ray. Exploration by these t...The presumed hairs of Holy Maria-Magdalena are studied here for mineral particles found on their surfaces, by the techniques of scanning electron microscopy coupled with energy dispersive X-ray. Exploration by these techniques of the hair surfaces allows us to observe and study some marble fragments that can originate from the walls of the sarcophagus in which Maria-Magdalena’s remains were kept. These new findings support the authenticity of the hair as traditionally reported in the French “tradition des Saints de Provence”.展开更多
Mammalian hair,as a key feature related to endothermy,physical protection,and camouflage,has a long geohistorical record that dates back even to the Mesozoic.However,the limited information on the taphonomy of hair hi...Mammalian hair,as a key feature related to endothermy,physical protection,and camouflage,has a long geohistorical record that dates back even to the Mesozoic.However,the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time.To address this,we conducted taphonomic experiments to simulate the transformation process of black hair.The changes in the morphological structure,microscopic characteristics,and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy,Fourier transform infrared(FTIR)spectroscopy,and Raman spectroscopy.Our results revealed that damage to the morphology of hair began at a mild temperature(150–175℃),and hair transformed into a fluid-like mass at a relatively high temperature(200℃).In addition,the morphological structure of melanosomes had relatively greater preservation potential than keratins did,and the microscopic features of melanosomes were persistently stable.The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased.Although the chemical signals were not lost completely,the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200℃),whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable,even at high temperatures(>200℃).These results were confirmed by principal component analysis(PCA)and principal component analysis linear discriminant analysis(PCA–LDA).In addition,the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid),which suggested that Raman spectroscopy can be used to detect melanin in fossils.展开更多
Take care of your hair to help it stay clean,strong and healthy.Wash your hair when it gets dirty,but not too often.For most people,that means every two to three days.People with oily hair wash it every one to two day...Take care of your hair to help it stay clean,strong and healthy.Wash your hair when it gets dirty,but not too often.For most people,that means every two to three days.People with oily hair wash it every one to two days.Use a brush or comb to keep your hair neat and smooth.It's also important to be gentle so you don't pull or break your hair.Never go to bed with wet hair.It can break easily when you sleep.Dry it before bed!展开更多
Hair loss,a multifactorial disorder characterized by follicular miniaturization and excessive shedding,significantly impairs psychological well-being and quality of life.Cyperus rotundus rhizome(CR),a traditional Chin...Hair loss,a multifactorial disorder characterized by follicular miniaturization and excessive shedding,significantly impairs psychological well-being and quality of life.Cyperus rotundus rhizome(CR),a traditional Chinese medicine used for various ailments,has not been evaluated for efficacy in treating hair loss.This study presents the first comprehensive assessment of the hair growth-promoting effects of ethanol extract from CR on mouse primary dermal papilla cells(MDPCs)and human immortalized hair DPCs(IHHDPCs),employing cell counting kit-8(CCK-8),scratch assay,reverse transcription-quantitative polymerase chain reaction(RT-q PCR),and Western blot(WB).CR treatment activated the Wnt/β-Catenin signaling pathway by upregulating Wnt10b,increasingβ-Catenin protein levels and promoting its nuclear translocation,while simultaneously downregulating transforming growth factor-beta 1(TGF-β1),BMP4,and dickkopf-related protein 1(DKK1)in MDPCs.These molecular changes enhanced cell proliferation and increased secretion of key growth factors—insulin-like growth factor 1(IGF1),keratinocyte growth factor(KGF),and vascular endothelial growth factor(VEGF)—thereby stimulating hair growth and prolonging the anagen phase,which was confirmed in an ex vivo hair follicle(HF)organ culture model.Chromatographic analysis identified the petroleum ether fraction(CRP),enriched in sesquiterpenes,as the primary bioactive component.Both CR and CRP promoted IHHDPC proliferation,migration,and growth factor expression through activation of the Wnt/β-Catenin pathway,with CRP exhibiting superior bioactivity.Furthermore,both treatments stimulated HF cycling,increased follicular density,and upregulated Ki67 andβ-Catenin expression in the dorsal skin of C57BL/6 mice.Collectively,these findings demonstrate that CR and CRP promote hair growth and modulate the hair cycle via enhancement of Wnt/β-Catenin signaling,providing a scientific basis for the potential clinical application of C.rotundus rhizomes in hair loss therapy and the development of related pharmaceuticals or cosmetics.展开更多
Hearing and balance disorders are significant health issues primarily caused by developmental defects or the irreversible loss of sensory hair cells(HCs).ldentifying the underlying genes involved in the morphogenesis ...Hearing and balance disorders are significant health issues primarily caused by developmental defects or the irreversible loss of sensory hair cells(HCs).ldentifying the underlying genes involved in the morphogenesis and development of HCs is crucial.Our current study highlights rhpn2,a member of rho-binding proteins,as essential for vestibular HC development.The rhpn2 gene is highly expressed in the crista and macula HCs.Loss of rhpn2 function in zebrafish reduces the otic vesicle area and vestibular HC number,accompanied by vestibular dysfunction.Shorter stereocilia and compromised mechanotransduction channel function are found in the crista HCs of rhpn2 mutants.Transcriptome RNA sequencing analysis predicts the potential interaction of rhpn2 with rhoab.Furthermore,co-immunoprecipitation confirms that Rhpn2 directly binds to RhoA,validating the interaction of the two proteins.rhpn2 knockout leads to a decreased expression of rock2b,a canonical RhoA signaling pathway gene.Treatment with the RhoA activator or exogenous rock2b mRNA injection mitigates crista HC stereocilia defects in rhpn2 mutants.This study uncovers the role of rhpn2 in vestibular HC development and stereocilia formation via mediating the RhoA signaling pathway,providing a target for the treatment of balance disorders.展开更多
The mammalian cochlea relies on outer and inner hair cells(OHCs/IHCs)for sound amplification and signal transmission.Rab3-interacting molecular binding protein 2(RIMBP2),expressed in receptor cells and neurons at syna...The mammalian cochlea relies on outer and inner hair cells(OHCs/IHCs)for sound amplification and signal transmission.Rab3-interacting molecular binding protein 2(RIMBP2),expressed in receptor cells and neurons at synaptic active zones,remains poorly characterized in hearing.We therefore generated a Rimbp2 knockout(KO)mouse model(Rimbp^(2-/-)),which exhibited severe hearing loss with elevated thresholds,prolonged latencies,and reduced amplitudes in auditory brainstem response Wave I.OHC loss via apoptosis was correlated with threshold elevation.In IHCs,patch-clamp recordings revealed reduced exocytosis,including a diminished readily-releasable pool,impaired sustained release,and blocked fast endocytosis.Immunostaining showed unchanged ribbon synapse numbers but positional shifts in the basal pole of KO IHCs.These findings demonstrated RIMBP2’s essential role in OHC survival and its broader regulatory functions in IHC synaptic transmission than previously recognized.展开更多
With the increasing demand for understanding skin physiology and advancing regenerative medicine,in vitro three-dimensional(3D)functional skin tissue models have become vital tools in dermatological research.These mod...With the increasing demand for understanding skin physiology and advancing regenerative medicine,in vitro three-dimensional(3D)functional skin tissue models have become vital tools in dermatological research.These models effectively mimic the complex structure and functions of human skin.This review comprehensively discusses the latest advancements in construction techniques,material selection,and applications of 3D skin models.It highlights the advantages and challenges associated with cutting-edge technologies such as layer-by-layer cell coating,3D bioprinting,bio-spray technology,and photolithographic microfabrication in creating highly realistic skin models.Moreover,it examines the wide-ranging applications of 3D skin models,includingelucidation of skin disease mechanisms,investigation of skin barrier functions,studies on skin aging and repair,hair regeneration,efficacy screening of therapeutic agents,cosmetic safety assessment,and personalized medicine.Finally,this review anticipates future trends in developing 3D skin models with greater structural and functional complexity,enhanced multifunctionality,and improved clinical translation.展开更多
Vestibular hair cells(HCs)in the inner ear,crucial for balance and spatial orientation,are classified into type I and type II subtypes,but the mechanisms regulating their differentiation remain unclear.In this study,w...Vestibular hair cells(HCs)in the inner ear,crucial for balance and spatial orientation,are classified into type I and type II subtypes,but the mechanisms regulating their differentiation remain unclear.In this study,we examined the role of Pou4f3,an important transcription factor,in vestibular HC differentiation using Pou4f3^(DTR/DTR)(deficient)and Pou4f3CreER/CreER(knockout)mouse models.In Pou4f3-deficient mice,the HC number decreased,and immature HCs failed to develop type I characteristics,indicating a developmental arrest.While type II HCs differentiated normally,Pou4f3 deficiency disrupted HC bundle formation and cell polarity.Findings from knockout models further confirmed the essential role of Pou4f3 in vestibular HC subtype specification.This study underscores the critical role of Pou4f3 in determining vestibular HC subtypes and offers insights into potential strategies for restoring vestibular function through HC regeneration.展开更多
Cochlear hair cell(HC)damage is a primary cause of sensorineural hearing loss.In this study,we performed metabolomic profiling of cochlear sensory epithelium following neomycin-induced HC injury and identified elevate...Cochlear hair cell(HC)damage is a primary cause of sensorineural hearing loss.In this study,we performed metabolomic profiling of cochlear sensory epithelium following neomycin-induced HC injury and identified elevated arginine metabolism as a key metabolic characteristic of damaged HCs.Using a highly sensitive and specific biosensor,we confirmed that injury induced an increase in arginine levels within cochlear HCs.By manipulating the levels of arginine and its downstream metabolites,we discovered that unmetabolized arginine exerts a strong protective effect on cochlear HCs,independent of its downstream metabolites,such as nitric oxide.Furthermore,integrated metabolomic and transcriptomic analyses revealed that arginine plays a critical role in reprogramming phospholipid metabolism.Arginine supplementation enhanced membrane phospholipid saturation through the Lands cycle and de novo lipogenesis,and protected HCs from phospholipid peroxidation-induced membrane damage and subsequent cell death.Notably,arginine supplementation protected hearing from both noise-and aminoglycoside-induced injury in mice.These findings underscore the role of unmetabolized arginine in modulating phospholipid metabolism and preventing membrane damage in cochlear HCs,highlighting that targeting phospholipid metabolism is an effective hearing protection strategy.展开更多
Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration vi...Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration via paracrine signaling;however,their clinical applications are limited by potential risks such as tumorigenesis and xenogeneic immune rejection,which are similar to the risks associated with other stem cell transplantations.The present study therefore focuses on small extracellular vesicles derived from hair follicle neural crest stem cells,which preserve the bioactive properties of the parent cells while avoiding the transplantation-associated risks.In vitro,small extracellular vesicles derived from hair follicle neural crest stem cells significantly enhanced the proliferation,migration,tube formation,and barrier function of perineurial cells,and subsequently upregulated the expression of tight junction proteins.Furthermore,in a rat model of sciatic nerve defects bridged with silicon tubes,treatment with small extracellular vesicles derived from hair follicle neural crest stem cells resulted in higher tight junction protein expression in perineurial cells,thus facilitating neural tissue regeneration.At 10 weeks post-surgery,rats treated with small extracellular vesicles derived from hair follicle neural crest stem cells exhibited improved nerve function recovery and reduced muscle atrophy.Transcriptomic and micro RNA analyses revealed that small extracellular vesicles derived from hair follicle neural crest stem cells deliver mi R-21-5p,which inhibits mothers against decapentaplegic homolog 7 expression,thereby activating the transforming growth factor-β/mothers against decapentaplegic homolog signaling pathway and upregulating hyaluronan synthase 2 expression,and further enhancing tight junction protein expression.Together,our findings indicate that small extracellular vesicles derived from hair follicle neural crest stem cells promote the proliferation,migration,and tight junction protein formation of perineurial cells.These results provide new insights into peripheral nerve regeneration from the perspective of perineurial cells,and present a novel approach for the clinical treatment of peripheral nerve defects.展开更多
Mechanosensors,as the core component of a proprioceptive system,can detect many types of mechanical signals in their surroundings,such as force signals,displacement signals,and vibration signals.It is understandable t...Mechanosensors,as the core component of a proprioceptive system,can detect many types of mechanical signals in their surroundings,such as force signals,displacement signals,and vibration signals.It is understandable that the development of an all-new mechanosensory structure that can be widely used is highly desirable.This is because it can markedly improve the detection performance of mechanosensors.Coincidentally,in nature,optimized microscale trigger hairs of Venus flytrap are ingeniously used as a mechanosensory structure.These trigger hairs are utilized for tactile mechanosensilla to efficiently detect external mechanical stimuli.Biological trigger hair-based mechanosensilla offer an all-new bio-inspired strategy.This strategy utilizes the notch structure and variable stiffness to enhance the perceptual performance of mechanosensors.In this study,the structure-performance-application coupling relationship of trigger hair-based mechanosensors is explored through experiment and analysis.An artificial trigger hair-based mechanosensor is developed by mimicking the deformation properties of the Venus flytrap trigger hair.This bio-inspired mechanosensor shows excellent performance in terms of mechanical stability,response time,and sensitivity to mechanical signals.展开更多
From June 7-10 hair and beauty specialists from 20 countries in Asia gathered in Beijing to take part in the 1994 ⅩⅧ Asian Hairstyling and Make-up Competition. This was the first time the event was held in China. At...From June 7-10 hair and beauty specialists from 20 countries in Asia gathered in Beijing to take part in the 1994 ⅩⅧ Asian Hairstyling and Make-up Competition. This was the first time the event was held in China. At the same time an international cosmetic, hair and skin care products oriental beauty exposition also was taking place. Throughout history men and women have paid attention to physical beauty, both in the West and the East,展开更多
The genetic identities of Ca2+ channels in root hair (RH) tips essential for constitutive RH growth have remained elusive for decades. Here, we report the identification and characterization of three cyclicnucleotide-...The genetic identities of Ca2+ channels in root hair (RH) tips essential for constitutive RH growth have remained elusive for decades. Here, we report the identification and characterization of three cyclicnucleotide-gated channel (CNGC) family members, CNGC5, CNGC6, and CNGC9, as Ca2+ channels essential for constitutive RH growth in Arabidopsis. We found that the cngc5-1cngc6-2cngc9-1 triple mutant(designated shrh1) showed significantly shorter and branching RH phenotypes as compared with thewild type. The defective RH growth phenotype of shrh1 could be rescued by either the expression ofCNGC5, CNGC6, or CNGC9 single gene or by the supply of high external Ca2+, but could not be rescuedby external K+ supply. Cytosolic Ca2+ imaging and patch-clamp data in HEK293T cells showed that thesethree CNGCs all function as Ca2+-permeable channels. Cytosolic Ca2+ imaging in growing RHs furthershowed that the Ca2+ gradients and their oscillation in RH tips were dramatically attenuated in shrh1compared with those in the wild type. Phenotypic analysis revealed that these three CNGCs are Ca2+ channels essential for constitutive RH growth, with different roles in RHs from the conditional player CNGC14.Moreover, we found that these three CNGCs are involved in auxin signaling in RHs. Taken together, ourstudy identified CNGC5, CNGC6, and CNGC9 as three key Ca2+ channels essential for constitutive RHgrowth and auxin signaling in Arabidopsis.展开更多
The availability in the soil of potassium(K^(+)),a poorly mobile macronutrient required in large quantities for plant growth,is generally suboptimal for crop production in the absence of fertilization,making improveme...The availability in the soil of potassium(K^(+)),a poorly mobile macronutrient required in large quantities for plant growth,is generally suboptimal for crop production in the absence of fertilization,making improvement of the ability of crops to adapt to K^(+)deficiency stress a major issue.Increasing the uptake capacity of the root system is among the main strategies to achieve this goal.Here,we report an integrative approach to examine the effect of K^(+)deficiency on the development of young plant entire root system,including root hairs which are known to provide a significant contribution to the uptake of poorly mobile nutrients such as K^(+),in two genetically distant wheat varieties.A rhizobox-type methodology was developed to obtain highly-resolved images of root and root hairs,allowing to describe global root and root hair traits over the whole root system via image analysis procedures.The two wheat varieties responded differently to the K^(+)shortage:Escandia,a wheat ancestor,reduced shoot biomass in condition of K^(+)shortage and substantially increased the surface area of its root system,specifically by increasing the total root hair area.Oued Zenati,a landrace,conversely appeared unresponsive to the K^(+)shortage but was shown to constitutively express,independently of the external K^(+)availability,favorable traits to cope with reduced K^(+)availability,among which a high total root hair area.Thus,valuable information on root system adaptation to K^(+)deficiency was provided by global analyses including root hairs,which should also be relevant for other nutrient stresses.展开更多
基金Supported by National Special Fund for Forestry Research in the Public Interest(201004094)~~
文摘[Objective] The paper was to compare the infrared spectra of straight guard hairs of leopard cat and golden cat. [Method] The straight guard hairs of leopard cat and golden cat were detected and analyzed by FTIR （Fourier Transform Infrared Spectroscopy）. [Result] There was significant interspecific difference in the infrared spectra and second derivative spectra for the middle part of guard hair. An evident M-shaped bimodal absorption peak appeared in golden cat at 648 and 654 cm-1, respectively, while did not appear in leopard cat. The second derivative spec-tra of golden cat at wave numbers from 709 to 763 cm -1 were mainly unimodal peaks with strong peak intensity, while that of leopard cat mainly was M-shaped bi-modal absorption peak with weak peak intensity. It indicated that there was obvious difference in the structure of protein side chain in guard hairs of these two animals. [Conclusion] The FTIR analysis showed great application foreground in the study of animal hairs for interspecific identification.
文摘The taxonomic status of long-tailed field mouse (Apodemus orestes) is still uncertain up to now.Some scholars regarded it as a subspecies or a synonym of dragon field mouse (A.draco),while other scholars considered it a valid species.In the study,five specimens of adult long-tailed field mouse,dragon field mouse and Chevrier's field mouse (A.chevrieri) (as a contrast) were chosen respectively.After treated,with the eyepiece micrometer in the inverted microscope,we made measurements of the widths of hairs and medullas and then calculated the medullary indexes of straight guard hairs from around the mouth,head,back,abdomen and forelimb of each species.The results indicate that,viewing at each of the five parts and the mixture of the five parts,there are no significant differences between A.orestes and A.draco,Significant differences can be found between A.orestes & A.chevrieri and A.draco & A.chevrieri though.The standpoint that A.orestes was listed as a valid species is not supported by this study.
基金sponspored by research opening fund of State Key Laboratory of Environmental Geochemistry,Guiyang,Guizhou Province,China with grant No.SKLEG2017910。
文摘In recent times,there had been reported cases of Pb poisoning in Anka gold mining area,Northwest Nigeria.Therefore,this study was carried out to determine the extent of bioaccumulation of heavy metals in the hairs and nails of children in the area.Forty samples(twenty nails and twenty hairs)samples were collected from ten boys and ten girls of ages 5–9 residing in the area.To ascertain the sources of heavy metals in children,15 soils samples,15 groundwater samples,5 samples of mine tailings,and 5 plants samples were collected.Hair and nails of the subjects were collected using internationally acceptable techniques.All samples were kept in uncontaminated ziplock bags prior to laboratory preparation and analysis.The samples were cleaned using nonionic detergent(triton X-100)and deionized water.The hairs and nails were digested with 10 mL of 6:1 mixture of nitric acid and perchloric acid.The soils,mine tailings,and plants were air-dried at room temperature,sieved,and chemically digested using the aqua regia method.The concentrations of metals in all the samples were determined using highperformance liquid chromatography–inductively coupled plasma–mass spectrometry.Statistical analysis was employed to unravel potential sources of metals in the media.Results showed that heavy metals in children of the area are above results from similar studies and pathological ranges for heavy metals in hairs and nails.Also,heavy metals in environmental media are above the recommended standards.Multivariate analysis showed that the metals are mainly from mining and other anthropogenic sources.Results of correlation between heavy metals in hairs and nails with those in geological samples revealed that heavy metal that bioaccumulates in the children of this area are mostly from contaminated environmental media.It is recommended that complete remediation and effective health education be carried out in the area.
文摘In polymorphic mammalian species that display multiple color forms, those with dark, or melanic pelage would be prone to overheating, especially if they live in warm climates, because their fur absorbs solar energy at a higher rate. However, experimental studies indicate that certain physical properties of fur of dark individuals appear to prevent, or minimize heat stress, although it is not clear what properties do so. Here, we tested the possibility that black-furred individuals simply have shorter or thinner hair fibers, which would create a lighter （in terms of weight） coat or one that allows greater air flow for evaporative coo- ling. We examined museum specimens of eastern fox squirrels Sciurus niger, a species native to the United States and one that displays brown, grey or all-black pelage color, and used image analysis procedures to quantify hairs from the dorsal surface and tail. From examination of 43 specimens （19 brown, 9 black and 15 grey）, and 1,720 hairs, we found no significant difference in hair lengths across color morphs, but significant differences in hair fiber widths. Black squirrels had thinner body hairs than other forms （7% thinner）, but thicker tail hairs （9% thicker） than the others. Given that the dorsal surface would be directly exposed to solar radiation, we interpret this to be an adaptation to prevent heat stress during the day. The thicker tail hairs may be an adapta- tion for nighttime thermoregulation, since squirrels sleep with their tails wrapped around their bodies. These results add to a growing literature body of the functional significance of mammalian pelage [Current Zoology 57 （6）： 731-736, 2011].
文摘The contents of total and methyl mercury in scalp hair samples of 1179 fishermenliving at a typical Hg-polluted region in Northeast China and 27 lying-in womenand their new born babies in Beijing have been determined by illstrumental neutronactivation analysis, gas chromatography (electron coupling) and other techniqlles.Only 18 of all fishermen have the Hg contents above 5 ig/g, which indicates that theHg pollution there has been substantially alleviated. The longitudinal Hg patternsof the lying-in women show a gradually lowering tendency during pregnant period.Further, the Hg contents of the new-born babies are generally above or close to those oftheir mothers, confirming the mechanism that the methyl Hg, an organic species of Hgwith high toxicity, is readily able to penetrate the placental barrier and accumulatedin fetus. Thus, the mercury poison hajs occurred at the early stage of pregnancy.
文摘The presumed hairs of Holy Maria-Magdalena are studied here for mineral particles found on their surfaces, by the techniques of scanning electron microscopy coupled with energy dispersive X-ray. Exploration by these techniques of the hair surfaces allows us to observe and study some marble fragments that can originate from the walls of the sarcophagus in which Maria-Magdalena’s remains were kept. These new findings support the authenticity of the hair as traditionally reported in the French “tradition des Saints de Provence”.
基金supported by the National Natural Science Foundation of China(Grant Nos.42288201&41922011)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB26000000)the Fundamental Research Funds for the Central Universities(Grant No.0206-14380219)。
文摘Mammalian hair,as a key feature related to endothermy,physical protection,and camouflage,has a long geohistorical record that dates back even to the Mesozoic.However,the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time.To address this,we conducted taphonomic experiments to simulate the transformation process of black hair.The changes in the morphological structure,microscopic characteristics,and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy,Fourier transform infrared(FTIR)spectroscopy,and Raman spectroscopy.Our results revealed that damage to the morphology of hair began at a mild temperature(150–175℃),and hair transformed into a fluid-like mass at a relatively high temperature(200℃).In addition,the morphological structure of melanosomes had relatively greater preservation potential than keratins did,and the microscopic features of melanosomes were persistently stable.The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased.Although the chemical signals were not lost completely,the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200℃),whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable,even at high temperatures(>200℃).These results were confirmed by principal component analysis(PCA)and principal component analysis linear discriminant analysis(PCA–LDA).In addition,the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid),which suggested that Raman spectroscopy can be used to detect melanin in fossils.
文摘Take care of your hair to help it stay clean,strong and healthy.Wash your hair when it gets dirty,but not too often.For most people,that means every two to three days.People with oily hair wash it every one to two days.Use a brush or comb to keep your hair neat and smooth.It's also important to be gentle so you don't pull or break your hair.Never go to bed with wet hair.It can break easily when you sleep.Dry it before bed!
基金supported by the Start-up Fund of China Pharmaceutical University(No.3150020057)。
文摘Hair loss,a multifactorial disorder characterized by follicular miniaturization and excessive shedding,significantly impairs psychological well-being and quality of life.Cyperus rotundus rhizome(CR),a traditional Chinese medicine used for various ailments,has not been evaluated for efficacy in treating hair loss.This study presents the first comprehensive assessment of the hair growth-promoting effects of ethanol extract from CR on mouse primary dermal papilla cells(MDPCs)and human immortalized hair DPCs(IHHDPCs),employing cell counting kit-8(CCK-8),scratch assay,reverse transcription-quantitative polymerase chain reaction(RT-q PCR),and Western blot(WB).CR treatment activated the Wnt/β-Catenin signaling pathway by upregulating Wnt10b,increasingβ-Catenin protein levels and promoting its nuclear translocation,while simultaneously downregulating transforming growth factor-beta 1(TGF-β1),BMP4,and dickkopf-related protein 1(DKK1)in MDPCs.These molecular changes enhanced cell proliferation and increased secretion of key growth factors—insulin-like growth factor 1(IGF1),keratinocyte growth factor(KGF),and vascular endothelial growth factor(VEGF)—thereby stimulating hair growth and prolonging the anagen phase,which was confirmed in an ex vivo hair follicle(HF)organ culture model.Chromatographic analysis identified the petroleum ether fraction(CRP),enriched in sesquiterpenes,as the primary bioactive component.Both CR and CRP promoted IHHDPC proliferation,migration,and growth factor expression through activation of the Wnt/β-Catenin pathway,with CRP exhibiting superior bioactivity.Furthermore,both treatments stimulated HF cycling,increased follicular density,and upregulated Ki67 andβ-Catenin expression in the dorsal skin of C57BL/6 mice.Collectively,these findings demonstrate that CR and CRP promote hair growth and modulate the hair cycle via enhancement of Wnt/β-Catenin signaling,providing a scientific basis for the potential clinical application of C.rotundus rhizomes in hair loss therapy and the development of related pharmaceuticals or cosmetics.
基金supported by grants from the Natural Science Foundation of Jiangsu Province(BK20221377 and BK20220607)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(22KJB180023)the National Natural Science Foundation of China Grants(32200783,32350017,and 92368104),and the Qing Lan Project of Jiangsu Province.
文摘Hearing and balance disorders are significant health issues primarily caused by developmental defects or the irreversible loss of sensory hair cells(HCs).ldentifying the underlying genes involved in the morphogenesis and development of HCs is crucial.Our current study highlights rhpn2,a member of rho-binding proteins,as essential for vestibular HC development.The rhpn2 gene is highly expressed in the crista and macula HCs.Loss of rhpn2 function in zebrafish reduces the otic vesicle area and vestibular HC number,accompanied by vestibular dysfunction.Shorter stereocilia and compromised mechanotransduction channel function are found in the crista HCs of rhpn2 mutants.Transcriptome RNA sequencing analysis predicts the potential interaction of rhpn2 with rhoab.Furthermore,co-immunoprecipitation confirms that Rhpn2 directly binds to RhoA,validating the interaction of the two proteins.rhpn2 knockout leads to a decreased expression of rock2b,a canonical RhoA signaling pathway gene.Treatment with the RhoA activator or exogenous rock2b mRNA injection mitigates crista HC stereocilia defects in rhpn2 mutants.This study uncovers the role of rhpn2 in vestibular HC development and stereocilia formation via mediating the RhoA signaling pathway,providing a target for the treatment of balance disorders.
基金supported by grants from the National Key R&D Program of China(2021YFA1101300,2021YFA1101800,2020YFA0112503,and 2024YFC2511103)the National Natural Science Foundation of China(82330033,82030029,82401375,81970882,92149304,and 81970883)+7 种基金the Natural Science Foundation of Jiangsu Province(BK20232007)the Science and Technology Department of Sichuan Province(2021YFS0371)Shenzhen Fundamental Research Program(JCYJ20210324125608022)the Open Project Fund of Guangdong Academy of Medical Sciences(YKY-KF202201)Beijing Natural Science Foundation(Z200019)the Jiangsu Provincial Scientific Research Center of Applied Mathematics(BK20233002)the China Postdoctoral Science Foundation(2023TQ0056,2023M730575,and GZC20230435)Jiangsu Funding Program for Excellent Postdoctoral Talent(2023ZB822).
文摘The mammalian cochlea relies on outer and inner hair cells(OHCs/IHCs)for sound amplification and signal transmission.Rab3-interacting molecular binding protein 2(RIMBP2),expressed in receptor cells and neurons at synaptic active zones,remains poorly characterized in hearing.We therefore generated a Rimbp2 knockout(KO)mouse model(Rimbp^(2-/-)),which exhibited severe hearing loss with elevated thresholds,prolonged latencies,and reduced amplitudes in auditory brainstem response Wave I.OHC loss via apoptosis was correlated with threshold elevation.In IHCs,patch-clamp recordings revealed reduced exocytosis,including a diminished readily-releasable pool,impaired sustained release,and blocked fast endocytosis.Immunostaining showed unchanged ribbon synapse numbers but positional shifts in the basal pole of KO IHCs.These findings demonstrated RIMBP2’s essential role in OHC survival and its broader regulatory functions in IHC synaptic transmission than previously recognized.
文摘With the increasing demand for understanding skin physiology and advancing regenerative medicine,in vitro three-dimensional(3D)functional skin tissue models have become vital tools in dermatological research.These models effectively mimic the complex structure and functions of human skin.This review comprehensively discusses the latest advancements in construction techniques,material selection,and applications of 3D skin models.It highlights the advantages and challenges associated with cutting-edge technologies such as layer-by-layer cell coating,3D bioprinting,bio-spray technology,and photolithographic microfabrication in creating highly realistic skin models.Moreover,it examines the wide-ranging applications of 3D skin models,includingelucidation of skin disease mechanisms,investigation of skin barrier functions,studies on skin aging and repair,hair regeneration,efficacy screening of therapeutic agents,cosmetic safety assessment,and personalized medicine.Finally,this review anticipates future trends in developing 3D skin models with greater structural and functional complexity,enhanced multifunctionality,and improved clinical translation.
基金supported by the National Natural Science Foundation of China(82271159,82071049,82425018,and 82101219)the STI2030-Major Projects(2022ZD0205400).
文摘Vestibular hair cells(HCs)in the inner ear,crucial for balance and spatial orientation,are classified into type I and type II subtypes,but the mechanisms regulating their differentiation remain unclear.In this study,we examined the role of Pou4f3,an important transcription factor,in vestibular HC differentiation using Pou4f3^(DTR/DTR)(deficient)and Pou4f3CreER/CreER(knockout)mouse models.In Pou4f3-deficient mice,the HC number decreased,and immature HCs failed to develop type I characteristics,indicating a developmental arrest.While type II HCs differentiated normally,Pou4f3 deficiency disrupted HC bundle formation and cell polarity.Findings from knockout models further confirmed the essential role of Pou4f3 in vestibular HC subtype specification.This study underscores the critical role of Pou4f3 in determining vestibular HC subtypes and offers insights into potential strategies for restoring vestibular function through HC regeneration.
基金supported by the National Natural Science Foundation of China(82271159,82425018,82071049,81830029,82192860,81922018,82201283,82101219,and 82192861)Shanghai Clinical Medical Research Center for Otolaryngology Diseases(20MC1920200)the STI2030-Major Projects(2022ZD0205400).
文摘Cochlear hair cell(HC)damage is a primary cause of sensorineural hearing loss.In this study,we performed metabolomic profiling of cochlear sensory epithelium following neomycin-induced HC injury and identified elevated arginine metabolism as a key metabolic characteristic of damaged HCs.Using a highly sensitive and specific biosensor,we confirmed that injury induced an increase in arginine levels within cochlear HCs.By manipulating the levels of arginine and its downstream metabolites,we discovered that unmetabolized arginine exerts a strong protective effect on cochlear HCs,independent of its downstream metabolites,such as nitric oxide.Furthermore,integrated metabolomic and transcriptomic analyses revealed that arginine plays a critical role in reprogramming phospholipid metabolism.Arginine supplementation enhanced membrane phospholipid saturation through the Lands cycle and de novo lipogenesis,and protected HCs from phospholipid peroxidation-induced membrane damage and subsequent cell death.Notably,arginine supplementation protected hearing from both noise-and aminoglycoside-induced injury in mice.These findings underscore the role of unmetabolized arginine in modulating phospholipid metabolism and preventing membrane damage in cochlear HCs,highlighting that targeting phospholipid metabolism is an effective hearing protection strategy.
基金supported by the National Natural Science Foundation of China,No.81571211(to FL)the Natural Science Foundation of Shanghai,No.22ZR1476800(to CH)。
文摘Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration via paracrine signaling;however,their clinical applications are limited by potential risks such as tumorigenesis and xenogeneic immune rejection,which are similar to the risks associated with other stem cell transplantations.The present study therefore focuses on small extracellular vesicles derived from hair follicle neural crest stem cells,which preserve the bioactive properties of the parent cells while avoiding the transplantation-associated risks.In vitro,small extracellular vesicles derived from hair follicle neural crest stem cells significantly enhanced the proliferation,migration,tube formation,and barrier function of perineurial cells,and subsequently upregulated the expression of tight junction proteins.Furthermore,in a rat model of sciatic nerve defects bridged with silicon tubes,treatment with small extracellular vesicles derived from hair follicle neural crest stem cells resulted in higher tight junction protein expression in perineurial cells,thus facilitating neural tissue regeneration.At 10 weeks post-surgery,rats treated with small extracellular vesicles derived from hair follicle neural crest stem cells exhibited improved nerve function recovery and reduced muscle atrophy.Transcriptomic and micro RNA analyses revealed that small extracellular vesicles derived from hair follicle neural crest stem cells deliver mi R-21-5p,which inhibits mothers against decapentaplegic homolog 7 expression,thereby activating the transforming growth factor-β/mothers against decapentaplegic homolog signaling pathway and upregulating hyaluronan synthase 2 expression,and further enhancing tight junction protein expression.Together,our findings indicate that small extracellular vesicles derived from hair follicle neural crest stem cells promote the proliferation,migration,and tight junction protein formation of perineurial cells.These results provide new insights into peripheral nerve regeneration from the perspective of perineurial cells,and present a novel approach for the clinical treatment of peripheral nerve defects.
基金supported by the National Natural Science Foundation of China(Grant nos.52005355 and 52005356)the Natural Science Foundation of Jiangsu Province(BK2020881).
文摘Mechanosensors,as the core component of a proprioceptive system,can detect many types of mechanical signals in their surroundings,such as force signals,displacement signals,and vibration signals.It is understandable that the development of an all-new mechanosensory structure that can be widely used is highly desirable.This is because it can markedly improve the detection performance of mechanosensors.Coincidentally,in nature,optimized microscale trigger hairs of Venus flytrap are ingeniously used as a mechanosensory structure.These trigger hairs are utilized for tactile mechanosensilla to efficiently detect external mechanical stimuli.Biological trigger hair-based mechanosensilla offer an all-new bio-inspired strategy.This strategy utilizes the notch structure and variable stiffness to enhance the perceptual performance of mechanosensors.In this study,the structure-performance-application coupling relationship of trigger hair-based mechanosensors is explored through experiment and analysis.An artificial trigger hair-based mechanosensor is developed by mimicking the deformation properties of the Venus flytrap trigger hair.This bio-inspired mechanosensor shows excellent performance in terms of mechanical stability,response time,and sensitivity to mechanical signals.
文摘From June 7-10 hair and beauty specialists from 20 countries in Asia gathered in Beijing to take part in the 1994 ⅩⅧ Asian Hairstyling and Make-up Competition. This was the first time the event was held in China. At the same time an international cosmetic, hair and skin care products oriental beauty exposition also was taking place. Throughout history men and women have paid attention to physical beauty, both in the West and the East,
基金This work was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB27020102)the National Natural Science Foundation of China(91635301,31570262,and 31770292).
文摘The genetic identities of Ca2+ channels in root hair (RH) tips essential for constitutive RH growth have remained elusive for decades. Here, we report the identification and characterization of three cyclicnucleotide-gated channel (CNGC) family members, CNGC5, CNGC6, and CNGC9, as Ca2+ channels essential for constitutive RH growth in Arabidopsis. We found that the cngc5-1cngc6-2cngc9-1 triple mutant(designated shrh1) showed significantly shorter and branching RH phenotypes as compared with thewild type. The defective RH growth phenotype of shrh1 could be rescued by either the expression ofCNGC5, CNGC6, or CNGC9 single gene or by the supply of high external Ca2+, but could not be rescuedby external K+ supply. Cytosolic Ca2+ imaging and patch-clamp data in HEK293T cells showed that thesethree CNGCs all function as Ca2+-permeable channels. Cytosolic Ca2+ imaging in growing RHs furthershowed that the Ca2+ gradients and their oscillation in RH tips were dramatically attenuated in shrh1compared with those in the wild type. Phenotypic analysis revealed that these three CNGCs are Ca2+ channels essential for constitutive RH growth, with different roles in RHs from the conditional player CNGC14.Moreover, we found that these three CNGCs are involved in auxin signaling in RHs. Taken together, ourstudy identified CNGC5, CNGC6, and CNGC9 as three key Ca2+ channels essential for constitutive RHgrowth and auxin signaling in Arabidopsis.
基金supported in part by a doctoral grant from the Algerian Ministry of Higher Education and Scientific Research(“bourse d’excellence du gouvernement algérien”to IM)by an ERANET EU Arimnet2 grant(no.618127)(to HS)by the French Institut National de Recherche pour l’Agriculture,l’Alimentation et l’Environnement(INRAE grant“Phenopili”from Biologie et Amélioration des Plantes Department)(to HS).
文摘The availability in the soil of potassium(K^(+)),a poorly mobile macronutrient required in large quantities for plant growth,is generally suboptimal for crop production in the absence of fertilization,making improvement of the ability of crops to adapt to K^(+)deficiency stress a major issue.Increasing the uptake capacity of the root system is among the main strategies to achieve this goal.Here,we report an integrative approach to examine the effect of K^(+)deficiency on the development of young plant entire root system,including root hairs which are known to provide a significant contribution to the uptake of poorly mobile nutrients such as K^(+),in two genetically distant wheat varieties.A rhizobox-type methodology was developed to obtain highly-resolved images of root and root hairs,allowing to describe global root and root hair traits over the whole root system via image analysis procedures.The two wheat varieties responded differently to the K^(+)shortage:Escandia,a wheat ancestor,reduced shoot biomass in condition of K^(+)shortage and substantially increased the surface area of its root system,specifically by increasing the total root hair area.Oued Zenati,a landrace,conversely appeared unresponsive to the K^(+)shortage but was shown to constitutively express,independently of the external K^(+)availability,favorable traits to cope with reduced K^(+)availability,among which a high total root hair area.Thus,valuable information on root system adaptation to K^(+)deficiency was provided by global analyses including root hairs,which should also be relevant for other nutrient stresses.
