RESUMO
Organisms display a remarkable diversity in their shapes. Although substantial progress has been made in unraveling the mechanisms that govern cell fate determination during development, the mechanisms by which fate-determined cells give rise to the final shapes of organisms remain largely unknown. This study describes in detail the process of the final shape formation of the tarsus, which is near the distal tip of the adult leg, during the pupal stage in Drosophila melanogaster. Days-long live imaging revealed unexpectedly complicated cellular dynamics. The epithelial cells transiently form the intriguing structure, which we named the Parthenon-like structure. The basal surface of the epithelial cells and localization of the basement membrane protein initially show a mesh-like structure and rapidly shrink into the membranous structure during the formation and disappearance of the Parthenon-like structure. Furthermore, macrophage-like cells are observed moving around actively in the Parthenon-like structure and engulfing epithelial cells. The findings in this research are expected to significantly contribute to our understanding of the mechanisms involved in shaping the final structure of the adult tarsus.
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Stick and leaf insects (Phasmatodea) are exclusively herbivores. As they settle in a broad range of habitats, they need to attach to and walk on a wide variety of plant substrates, which can vary in their surface free energy (SFE). The adhesive microstructures (AMs) on the euplantulae of phasmids are assumed to be adapted to such substrate properties. Moreover, the natural substrates can often be covered with water as a result of high relative humidity or rain. Although considerable experimental research has been carried out on different aspects of stick insect attachment, the adaptations to cope with the influence of flooded water on attachment performance remain unclear. To elucidate the role of AMs in this context, we here measured attachment forces in three species of stick insects with different AMs. The results show that attachment forces of the three species studied were influenced by the SFE and the presence of water: they all showed higher pull-off (vertical) and traction (horizontal) forces on dry surfaces, compared with when the surfaces were covered with a water film. However, the extent to which the surface properties influenced attachment differed depending on the species and its AMs. All three species showed approximately the same attachment performance on dry surfaces with different surface free energy but maintained attachment underwater to different extents.
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Adesivos , Insetos , Animais , Fenômenos Biomecânicos , Propriedades de Superfície , Água , AdesividadeRESUMO
St. Paul of Tarsus, in 1 Thessalonians (5:16), urges his suffering addressees to 'rejoice always.' This can seem not only inappropriate, but even inhumane. It can be argued, however, that a unique therapy to strengthen the disheartened is at work. St. Paul applies to his readers what can be described as an authorial therapeutic method-"rejoice therapy"-to help them create and shape their joy despite the difficult situation in which they live. St. Paul employs more than just rhetorical strategies in order to achieve this intended effect. St. Paul provides his readers with practical and universalistic techniques, which can continue to have therapeutic value today.
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Felicidade , Religião , HumanosRESUMO
This report describes periarticular plasma cell tumors with abundant amyloid in 11 cats. The tarsus was the most commonly affected joint (10/11), and the masses were often circumferential around the tarsal joint, involving the dermis and subcutis. The 2 cases in which synovium was examined had neoplastic cells expanding the synovium. Three of the 5 cases staged radiographically had bony lysis of the affected joint. Cutaneous biopsy specimens often consisted of more amyloid than plasma cells, making the diagnosis difficult on small samples. Follow-up information was available in 7 cases; in those cases, the median survival was 194 days (range 53-671 days). Four cases had confirmed metastases, most often to regional lymph nodes, liver, and spleen. Although canine cutaneous plasma cell tumors are typically benign, those with abundant amyloid surrounding the joints of cats may involve deeper tissues and have a more aggressive behavior. These tumors can be difficult to diagnose due to low cellularity and abundant amyloid.
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Amiloidose , Doenças do Gato , Doenças do Cão , Osteólise , Plasmocitoma , Amiloide , Amiloidose/patologia , Amiloidose/veterinária , Animais , Doenças do Gato/diagnóstico , Doenças do Gato/patologia , Gatos , Doenças do Cão/patologia , Cães , Osteólise/veterinária , Plasmócitos , Plasmocitoma/patologia , Plasmocitoma/veterináriaRESUMO
A 71-year-old female with invasive squamous cell carcinoma of the lower eyelid involving the ocular surface underwent surgical excision with negative margins and a subsequent reconstruction. The posterior lamellar defect was reconstructed with a Hughes tarsoconjunctival flap, and the anterior lamellar defect was reconstructed by advancing the lower eyelid skin. Three years later, the patient presented with signs suspicious for recurrence involving the tarsoconjunctival graft: a nodule along the mucocutaneus junction, symblepharon, and forniceal shortening. Repeat scouting biopsies showed variable degrees of moderate to severe squamous dysplasia so the patient underwent a staged full thickness excision of the lower eyelid and involved conjunctiva followed by reconstruction. Direct immunofluorescence was not diagnostic for ocular cicatrcial pemphigoid. Permanent histopathologic sections did not show any carcinoma, but the full thickness excisions involving the prior Hughes tarsoconjunctival flap highlighted two notable alterations: the Meibomian glands were absent and the accessory lacrimal glands of Wolfring were transposed to the mucocutaneous junction of the reconstructed lower eyelid.
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BACKGROUND: Magnetic resonance imaging (MRI) is the most versatile and informative imaging modality for the diagnosis of locomotor injuries in many animal species; however, veterinary literature describing the MRI of the dromedary camel tarsus is lacking. Our purpose was to describe and compare the MRI images of twelve cadaveric tarsi, examined in a 1.5 Tesla MRI scanner, with their corresponding anatomical gross sections. Turbo spin-echo (TSE) T1-weighted (T1), T2-weighted (T2), proton density-weighted (PD), and short tau inversion recovery (STIR) sequences were obtained in 3 planes. Tarsi were sectioned in sagittal, dorsal, and transverse planes. MRI images from different sequences and planes were described and compared with the anatomical sections. RESULTS: The soft and osseous tissues of the dromedary camel tarsus could be clearly defined on MRI images and corresponded extensively with the gross anatomic sections. The obtained MRI images enabled comprehensive assessment of the anatomic relationships among the osseous and soft tissues of the camel tarsus. Several structure were evaluated that cannot be imaged using radiography or ultrasonography, including the transverse inter-tarsal ligaments, the talocalcaneal ligament, the short dorsal ligament, branches of the short medial and lateral collateral ligaments and the tarsometatarsal ligaments. Specific anatomical features regarding the dromedary camel tarsus were identified, including the fused second and third tarsal bone, an additional bundle of the short medial collateral ligament connecting the talus and metatarsus and the medial and lateral limbs of the long plantar ligament. CONCLUSIONS: MRI images provided a thorough evaluation of the normal dromedary camel tarsus. Information provided in the current study is expected to serve as a basis for interpretation in clinical situations.
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Imageamento por Ressonância Magnética/veterinária , Tarso Animal/diagnóstico por imagem , Animais , Camelus , Feminino , Masculino , Tarso Animal/anatomia & histologiaRESUMO
PURPOSE: The results of a technique with a double reinsertion of the aponeurosis to the tarsus and aponeurosis to Whitnall's ligament (ATW) were compared with a simple reinsertion of the aponeurosis to the tarsus (AT) in acquired aponeurotic palpebral ptosis surgery. METHODS: Analytical, observational, retrospective, cohort study. Seven hundred and twenty-two consecutive cases with acquired aponeurotic palpebral ptosis have been treated surgically between 2000 and 2012 and have been followed up for 5 years. The cases were divided into two cohorts according to the applied surgical technique (AT vs ATW). RESULTS: The mean postoperative MRD after 1 month in cohort AT was 1 mm lower than in ATW (3 ± 0.9 mm vs 4 ± 1 mm). The mean MRD in the long-term follow-up (5 years) was 1 mm lower in cohort AT than in ATW (2.9 ± 1.5 mm vs 3.9 ± 0.9 mm). The rate of long-term recurrence (5 years) was 15% higher in A-T than in A-T-W (20% vs 5%). 70.5% of the eyes studied intra-surgically presented gaps between the Whitnall ligament and the aponeurosis, an anatomical area that we describe as the upper transition zone (UTZ). In an independent analysis, only those patients with open UTZ were evaluated and it was observed that those operated with A-T-W presented elevations greater than 1 mm compared to those operated with the AT technique (4 ± 0.9 mm A-T-W vs 2.8 ± 1 mm A-T) and a much lower recurrence rate (5.4% A-T vs 38.09% A-T-W). CONCLUSIONS: In our study, the A-T-W technique achieved better results in terms of palpebral elevation and fewer recurrences compared to the A-T technique in all cases studied with aponeurotic ptosis. However, it particularly demonstrates its superiority in patients with large gaps in the UTZ.
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Aponeurose , Blefaroptose , Ligamentos , Aponeurose/cirurgia , Blefaroptose/diagnóstico , Blefaroptose/cirurgia , Pálpebras/cirurgia , Humanos , Ligamentos/cirurgia , Músculos Oculomotores/cirurgia , Estudos RetrospectivosRESUMO
We describe here the case of a female patient with type I diabetes who developed active Charcot neuroarthropathy in the foot. Due to therapeutic noncompliance, talus necrosis was discovered 2 years after the presentation of neuroarthropathy. The impact of untreated neuroarthropathy on the bone is commonly described as fracture and joint dislocation, but we describe the complete disappearance of the bony structure and its necrosis associated with active neuroarthropathy in a patient who refused offloading.
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Artropatia Neurogênica , Pé Diabético , Fraturas Ósseas , Artropatia Neurogênica/diagnóstico por imagem , Feminino , Pé , Fraturas Ósseas/diagnóstico por imagem , Humanos , NecroseRESUMO
Osteochondritis dissecans (OCD) of the distal intermediate ridge of the tibia (DIRT) is commonly identified on either the lateral to medial (LM) or dorso45°medial-plantarolateral oblique (D45M-PLO) projection of the tarsus. This manuscript describes a retrospective case series out of Hagyard Equine Medical Institute, for which medical records and radiographic projections of the tarsus were reviewed, consistent with Keeneland's repository requirements. This original investigation identified seven yearling Thoroughbred horses between 2008 and 2018 with radiographic signs of atypical osteochondrosis lesions within the tarsus. The atypical lesions, originating along the medial margin of the distal intermediate ridge of the tibia, were initially only diagnosed on the dorso10°lateral-plantaromedial (D10L-PMO) projection and were overlooked on the LM and D45M-PLO views. Following the diagnosis of osteochondrosis in these seven cases, the radiographs were reviewed and re-evaluated, but osteochondrosis and/or fragmentation could not be definitively diagnosed on the LM and/or D45M-PLO projections alone. Our findings highlight the importance of a complete radiographic study of the equine tarsus when screening horses for OCD lesions of the distal intermediate ridge of the tibia and that atypical DIRT lesions may go undetected if the D10L-PMO projection is not performed.
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Doenças dos Cavalos/diagnóstico por imagem , Osteocondrite Dissecante/veterinária , Tíbia/patologia , Animais , Feminino , Doenças dos Cavalos/patologia , Cavalos , Masculino , Osteocondrite Dissecante/diagnóstico por imagem , Osteocondrite Dissecante/patologia , Radiografia , Estudos Retrospectivos , Ossos do TarsoRESUMO
PURPOSE: To present the differentiating clinical findings between intratarsal keratinous cyst (IKC) and chalazion. METHOD: A retrospective review of medical records of all patients who presented between 2010 and 2018 at King Abdulaziz University Hospital with proven histopathological diagnosis of IKC was done. Complete ophthalmologic evaluation at presentation, surgical procedures performed, complications, histopathological findings, response to treatment and follow-up were recorded. RESULTS: Twelve patients were found to have IKC. All patients presented with an eyelid mass with no signs of local inflammation. All lesions were fixed to the tarsus with freely mobile overlying skin, which was found to be slightly pale compared to the surrounding skin in six patients. On palpation, IKC had well-defined boarders. Isolation with clear surgical plane for cyst excision was achieved in nine patients as they were superficially involving the tarsus. When IKC involved the deep part of the tarsus, bluish/ whitish nodules were seen upon eyelid eversion. Six patients were misdiagnosed and surgically treated as a chalazion elsewhere prior to presentation to us with recurrence. CONCLUSION: Differentiating IKC from chalazion can be challenging. Careful clinical evaluation helps reaching the right diagnosis and providing the correct treatment, which involves complete excision of IKC to prevent recurrence.
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Calázio , Doenças Palpebrais , Calázio/diagnóstico , Calázio/cirurgia , Doenças Palpebrais/diagnóstico , Doenças Palpebrais/cirurgia , Humanos , Queratinas , Recidiva Local de Neoplasia , Estudos RetrospectivosRESUMO
The arrangement of the tarsus has been used to differentiate afrotherian and laurasiatherian ungulates for more than a century, and it is often present in morphological matrices that include appendicular features. Traditionally, it has two states: (i) an alternating tarsus, where proximal elements are interlocked with central and distal elements positioned like the bricks of a wall; and (ii) a serial tarsus, where elements are not interlocked. Over the years, these states became synonymous with the presence or absence of an astragalocuboid contact. Within the South American order Notoungulata, a third disposition was recognized: the reversed alternating tarsus, associated with a calcaneonavicular contact. This state was considered to be a synapomorphy of 'advanced' Toxodontia families (Notohippidae, Leontiniidae and Toxodontidae), but a further inspection of its distribution shows that it occurs throughout Mammalia. Additionally, it overlaps the serial tarsus condition as originally defined, and it probably has no functional or phylogenetic significance. Calcaneonavicular and astragalocuboid contacts are non-exclusive, and their presence within a species, genus or family is not constant. Serial and alternating imply movements of the articulations of the mid-tarsus in the transverse axis, while reverse alternating refers to a small calcaneonavicular contact that sometimes occurs in a serial condition or to a significant displacement of the tarsal articulations in a different (proximodistal) axis. The proximodistal arrangement of the joints could be functionally significant. Two new states are observed and defined: (i) 'flipped serial', present in Macropodidae, in which the calcaneocuboid articulation is medially displaced and significantly larger than the astragalonavicular contact, but the relationships between proximal and central elements are one to one; and (ii) 'distal cuboid', an extreme proximodistal displacement of the astragalonavicular joint. Serial and alternating, as originally defined (i.e. without any reference to which bone contacts which), seem to be the best states for classifying tarsal arrangement though as the disposition of distal or central bones in relationship to proximal bones.
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Articulação do Tornozelo/anatomia & histologia , Mamíferos/anatomia & histologia , Ossos do Tarso/anatomia & histologia , AnimaisRESUMO
Idiopathic subepidermal calcinosis, also known as idiopathic calcinosis cutis, is a rare condition, which typically presents as a small, hard, subepithelial mass in the absence of systemic disease and trauma. We report on an atypical case of idiopathic calcinosis, which appeared in an otherwise healthy 61-year-old female along the tarsus of her right upper eyelid. The purpose of this case report is to demonstrate idiopathic calcinosis in an unusual location that is deep to the dermis and to discuss the vast differential diagnosis of this entity.
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Calcinose/patologia , Doenças Palpebrais/patologia , Antraquinonas/metabolismo , Biópsia , Calcinose/metabolismo , Calcinose/cirurgia , Cálcio/metabolismo , Doenças Palpebrais/metabolismo , Doenças Palpebrais/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Coloração e Rotulagem/métodosRESUMO
PURPOSE: To describe a clinical case of bilateral biopsy-proven IgG4-related disease confined to the tarsal plate. METHOD: Interventional case report. RESULTS: A 58-year-old woman presented with a tarsal swelling in the lateral part of the upper eyelids, with focal ulceration and mucus. Histology revealed fibrotic inflammation with increased IgG4-positive plasma cells fulfilling the criteria of IgG4-related disease (IgG4-RD). Serum IgG4 levels were increased, and pathological fluorodeoxyglucose uptake at positron emission tomography/CT scanning was restricted to the upper eyelids. After treatment with oral and topical prednisone, the tarsal lesions markedly regressed. CONCLUSIONS: Periorbital IgG4-RD may be confined to the tarsal plate. Treatment with systemic and topical steroids may induce significant regression.
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Pálpebras/patologia , Doença Relacionada a Imunoglobulina G4/complicações , Síndromes Neurocutâneas/etiologia , Transtornos da Pigmentação/etiologia , Administração Tópica , Biópsia , Feminino , Glucocorticoides/administração & dosagem , Humanos , Doença Relacionada a Imunoglobulina G4/diagnóstico , Pessoa de Meia-Idade , Síndromes Neurocutâneas/diagnóstico , Síndromes Neurocutâneas/tratamento farmacológico , Transtornos da Pigmentação/diagnóstico , Transtornos da Pigmentação/tratamento farmacológicoRESUMO
Triclosan (TCS), a commonly used antimicrobial compound, has recently been detected in the eggs of wild avian species. Exposure to TCS in rodents is known to interfere with thyroid hormone (TH), disrupt immune responses and cause liver disease. However, no attempt has been made to clarify the effects of TCS in avian species. The aim of this study is therefore to evaluate the toxic effects of in ovo exposure to TCS and explore the molecular mechanism by transcriptome analysis in the embryonic liver of a model avian species, chicken (Gallus gallus). Embryos were treated with graded concentration of TCS (0.1, 1 and 10⯵g/g egg) at Hamburger Hamilton Stage (HHS) 1 (1st day), followed by 20â¯days of incubation to HHS 46. At the administration of 10⯵g TCS/g egg, embryo mortality increased from 20% in control to 37% accompanied with 8% attenuation in tarsus length. While liver somatic index (LSI) in TCS treatments was enhanced, statistical difference was only observed at the treatment of 0.1⯵g TCS/g egg in females. The up-regulation of several crucial differentially expressed genes (DEGs) in transcriptome analysis suggested that TCS induced xenobiotic metabolism (e.g. CYP2C23a, CYP2C45 and CYP3A37 in males; CYP2C45 in females) and activated the thyroid hormone receptor (THR) - mediated downstream signaling (e.g. THRSPB and DIO2 in males; THRSPB in females). In females, TCS may further activate the lipogenesis signaling (e.g. ACSL5, ELOVL2) and repress the lipolysis signaling (e.g. ABHD5, ACAT2). A battery of enriched transcription factors in relation to these TCS-induced signaling and phenotypes were found, including activated SREBF1, PPARa, LXRa, and LXRb in males and activated GLI2 in females; COUP-TFII was predicted to be suppressed in both genders. Finally, we developed adverse outcome pathways (AOPs) that provide insights into the molecular mechanisms underlying the alteration of phenotypes.
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Anti-Infecciosos/toxicidade , Fígado/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Triclosan/toxicidade , Fatores Etários , Animais , Embrião de Galinha , Galinhas , Relação Dose-Resposta a Droga , Feminino , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Genótipo , Fígado/embriologia , Fígado/metabolismo , Masculino , Fenótipo , Mapas de Interação de Proteínas , Medição de Risco , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genéticaRESUMO
BACKGROUND: Incisional double-eyelid blepharoplasty is widely applied because of its extensive indications and robust results. The orbicularis-levator fixation method is an incisional approach that provides stronger adhesion than traditional techniques. However, there remains the risk of postoperative relapse or suture spitting out. METHODS: The authors introduced a modified technique for supratarsal crease formation. When necessary soft tissue removal was completed, the orbicularis oculi muscle was anchored on the tarsus. Then the muscle edges near canthus were reattached to prevent muscle retraction. For skin closure, the skin-pretarsal fascia-skin maneuver was adopted to enhance cicatricial adhesion. RESULTS: Six hundred and fifty-nine patients underwent double eyelidplasty by the same surgeon using this modified technique. Patients were followed up from 2 to 38 months, with a mean period of 15 months. Short-term complications included mild edema, bruising or reddish change of the upper eyelid, yet all gradually relieved in 6-8 weeks. Fourteen cases of palpebral fold asymmetry and nine cases of unsatisfactory fold formation near the inner canthus were encountered, and all the defects had been well improved by revision surgeries. Ninety-five percent of the patients were satisfied with the long-term outcomes, which showed as natural and well-defined palpebral folds without scar hypertrophy, suture spitting out or crease depression. Besides, no supratarsal crease drooping or disappearing was observed 3 years postoperatively. CONCLUSIONS: The authors introduced an orbicularis-tarsus fixation method for upper eyelid blepharoplasty. It is a reliable technique that enables high feasibility and long-lasting result, and with lower risk of suture spitting out. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Blefaroplastia/métodos , Pálpebras/cirurgia , Satisfação do Paciente , Técnicas de Sutura , Adolescente , Adulto , Fatores Etários , Povo Asiático/genética , China , Cicatriz/prevenção & controle , Estudos de Coortes , Estética , Pálpebras/anormalidades , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Estudos Retrospectivos , Fatores Sexuais , Decúbito Dorsal , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Reconstruction of the upper eyelids following traumatic, congenital and tumor surgeries is often difficult owing to a variety of reasons including the influence of the lacrimal system, visual system and aesthetic appearance. In most cases of the reconstruction in the upper eyelid tarsal plate is the main anatomical area that should be protected against the damage. The aim of this study is to investigate the types and the measurements of the tarsal plate of the upper eyelids in Anatolian population. METHODS: Fifty cadaver upper eyelids, tarsal plates were exposed to investigate the location, shape, position and their relationships to the upper eyelid. Their morphometric details such as linear analyses (vertical and horizontal) and ratio analyses were studied. As for the shape of the upper tarsal plate, it was categorized into three distinct types: sickle, trapezoid, and triangular type. RESULTS: The vertical height of the upper tarsal plate was the greatest at the central point 10.6 ± 1.1 mm, followed by the lateral point (7.81 ± 1.0 mm), and medial point (6.2 ± 0.8 mm) medially. The mean medial width of the upper tarsal plate was measured as 37.6 ± 4.1 mm and the lower width as 38.5 ± 4.6 mm. The base-central height ratio of the upper tarsal plate was approximately 0.28. For the upper eyelids, the shapes of tarsal plates were observed as sickle (48%), trapezoid (28%) and triangular (24%). Sickle type was the most frequent upper eyelid type. CONCLUSIONS: Considering the shielding function of the upper eyelid, tarsal plate, serves as fibrocartilaginous skeleton of the upper tarsal plate. In successful lid oculoplastic reconstructive surgery, tarsal plate may be restored by evaluating each patient individually to have symmetrical and youthful eyes. Although sickle tarsal plate is the most frequent type, personalized treatment requires measurement and classification. The findings manifest the necessity of oculoplastic surgical treatment peculiar to each individual. LEVEL OF EVIDENCE: I, Randomized controlled trial.
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Pálpebras/anatomia & histologia , Pálpebras/cirurgia , Procedimentos de Cirurgia Plástica , Adulto , Pontos de Referência Anatômicos , Cadáver , Pálpebras/lesões , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The present transmission and scanning electron microscopic study of the ultramorphology of the pliable attachment pads (arolium, euplantulae) of the Madagascar hissing cockroach Gromphadorhina portentosa reveals structural evidence for their function in producing, storing, and secreting an adhesion-mediating secretion and releasing it to the exterior. The exocrine epidermal tissue of both the arolium and the euplantula is significantly enlarged by numerous invaginations stretching into the hemolymph cavity. Its cells show large nuclei, numerous mitochondria, Golgi complexes, and a prominent rough-surfaced endoplasmic reticulum integrated within an electron-dense cytoplasm that contains numerous vesicles of diverse electron density and size. Invaginations of the cell membrane provide evidence for strong membrane turnover. The glandular epithelium of both the arolium and the euplantula releases the adhesion-mediating secretion into a subcuticular void from which it has to permeate the thick cuticle of the adhesive pads. The subcuticular void is compartmentalized by cuticle bands through which the adhesion-mediating secretion permeates via small canals. The secretion subsequently enters a larger storage reservoir before being received by a prominent sponge-like cuticle. The structural differences between the arolium and the euplantula consist of the number and length of the interdigitations spanning the hemolymph cavity, of the subdivision of the subcuticular reservoir by cuticle bands, and of the thickness of the sponge-like cuticle. The structural results are discussed with respect to the production of a chemically complex (emulsion-like) adhesive, its controlled release to the exterior, and the micromechanical properties of the cuticle of the pliable pad.
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Adesivos/análise , Baratas/anatomia & histologia , Baratas/ultraestrutura , Animais , Baratas/citologia , Microscopia Crioeletrônica , Células Epidérmicas , Epiderme/anatomia & histologia , Epiderme/ultraestrutura , Feminino , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , CaminhadaRESUMO
The present paper characterizes the attachment ability of males and females of Nezara viridula (Heteroptera: Pentatomidae) on artificial surfaces (smooth hydrophilic, smooth hydrophobic, different surface roughness) and on both leaf surfaces of the typical host plant species Vicia faba, using a centrifugal force tester and a traction force experiments set up. N. viridula is a serious crop pest in the world and shows attachment devices different from the so far investigated Heteroptera, with a tarsus characterized by distal smooth flexible pulvilli combined with claws and proximal ventral hairy pad. Notwithstanding the different body mass between the sexes, no difference was found between friction forces generated by females and males. Friction force was higher on hydrophilic surfaces than on hydrophobic ones and was lower on both sides of V. faba leaf compared with both hydrophilic and hydrophobic artificial smooth surfaces. On the surfaces with different roughness, the friction force values varied significantly, with the higher attachment ability on the surface with very high asperity size followed by the smooth surface. The lowest attachment was on the surfaces with intermediate asperity sizes. These results could be related to the specific combination of attachment devices of N. viridula.
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Heterópteros/fisiologia , Animais , Feminino , Fricção , Heterópteros/anatomia & histologia , MasculinoRESUMO
Elongation and invagination of epithelial tissues are fundamental developmental processes that contribute to the morphogenesis of embryonic and adult structures and are dependent on coordinated remodeling of cell-cell contacts. The morphogenesis of Drosophila leg imaginal discs depends on extensive remodeling of cell contacts and thus provides a useful system with which to investigate the underlying mechanisms. The small Rho GTPase regulator RhoGAP68F has been previously implicated in leg morphogenesis. It consists of on an N-terminal Sec14 domain and a C-terminal GAP domain. Here we examined the molecular function and role of RhoGAP68F in epithelial remodeling. We find that depletion of RhoGAP68F impairs epithelial remodeling from a pseudostratified to simple, while overexpression of RhoGAP68F causes tears of lateral cell-cell contacts and thus impairs epithelial integrity. We show that the RhoGAP68F protein localizes to Rab4 recycling endosomes and forms a complex with the Rab4 protein. The Sec14 domain is sufficient for localizing to Rab4 endosomes, while the activity of the GAP domain is dispensable. RhoGAP68F, in turn, inhibits the scission and movement of Rab4 endosomes involved in transport the adhesion proteins Fasciclin3 and E-cadherin back to cell-cell contacts. Expression of RhoGAP68F is upregulated during prepupal development suggesting that RhoGAP68F decreases the transport of key adhesion proteins to the cell surface during this developmental stage to decrease the strength of adhesive cell-cell contacts and thereby facilitate epithelial remodeling and leg morphogenesis.
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Proteínas de Drosophila/metabolismo , Drosophila/embriologia , Extremidades/embriologia , Proteínas Ativadoras de GTPase/metabolismo , Discos Imaginais/embriologia , Modelos Biológicos , Morfogênese/fisiologia , Animais , Caderinas/metabolismo , Adesão Celular/genética , Adesão Celular/fisiologia , Moléculas de Adesão Celular Neuronais/metabolismo , Endossomos/fisiologia , Imunofluorescência , Imunoprecipitação , Proteínas Luminescentes , Transporte Proteico/fisiologia , Interferência de RNA , Proteínas rab4 de Ligação ao GTP/metabolismo , Proteína Vermelha FluorescenteRESUMO
The capacity of non-native species to undergo rapid adaptive change provides opportunities to research contemporary evolution through natural experiments. This capacity is particularly true when considering ecogeographical rules, to which non-native species have been shown to conform within relatively short periods of time. Ecogeographical rules explain predictable spatial patterns of morphology, physiology, life history and behaviour. We tested whether Australian populations of non-native starling, Sturnus vulgaris, introduced to the country approximately 150 years ago, exhibited predicted environmental clines in body size, appendage size and heart size (Bergmann's, Allen's and Hesse's rules, respectively). Adult starlings (n = 411) were collected from 28 localities from across eastern Australia from 2011 to 2012. Linear models were constructed to examine the relationships between morphology and local environment. Patterns of variation in body mass and bill surface area were consistent with Bergmann's and Allen's rules, respectively (small body size and larger bill size in warmer climates), with maximum summer temperature being a strongly weighted predictor of both variables. In the only intraspecific test of Hesse's rule in birds to date, we found no evidence to support the idea that relative heart size will be larger in individuals which live in colder climates. Our study does provide evidence that maximum temperature is a strong driver of morphological adaptation for starlings in Australia. The changes in morphology presented here demonstrate the potential for avian species to make rapid adaptive changes in relation to a changing climate to ameliorate the effects of heat stress.