RESUMO
MYC amplification has been reported as a prominent feature of secondary angiosarcomas (SAS). The differential diagnosis between atypical vascular lesion (AVL) and low-grade angiosarcoma (AS) can be occasionally very difficult or even impossible, and MYC amplification status has been pointed as an important diagnostic tool to distinguish cutaneous vascular lesions of the breast. We assessed MYC amplification and protein expression status by fluorescent in situ hybridization (FISH) and immunohistochemistry (IHC), respectively, in 49 patients diagnosed with breast AS, and 30 patients diagnosed with post-radiation AVL of the breast. Clinical and pathological features, and follow-up data were collected, and survival analyses were performed. Among 37 patients with SAS, twenty patients had tumors with high-level MYC amplification and protein overexpression (54 %). None of primary angiosarcomas (PAS) or AVL cases showed MYC amplification or protein expression. Concordance between MYC amplification (FISH) and protein expression (IHC) was 100 % in AVL, PAS, and SAS. Survival analysis of the SAS patients demonstrates that those with MYC amplification had a significantly worse overall survival compared to cases without MYC amplification (P = 0.035). There was a non-significant trend toward a poor disease-free survival between cases with and without MYC amplification (P = 0.155). Our findings show that MYC amplification is a highly specific but poorly sensitive marker for SAS and, therefore, a negative result does not exclude the diagnosis of angiosarcoma. MYC amplification was associated with adverse prognosis, suggesting a prognostic role of MYC amplification status on SAS of the breast.
Assuntos
Neoplasias da Mama/genética , Hemangiossarcoma/genética , Neoplasias Induzidas por Radiação/genética , Proteínas Proto-Oncogênicas c-myc/genética , Neoplasias Cutâneas/genética , Malformações Vasculares/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Diagnóstico Diferencial , Intervalo Livre de Doença , Feminino , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Heterogeneidade Genética , Hemangiossarcoma/diagnóstico , Hemangiossarcoma/patologia , Humanos , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/diagnóstico , Neoplasias Induzidas por Radiação/patologia , Prognóstico , Proteínas Proto-Oncogênicas c-myc/biossíntese , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Malformações Vasculares/diagnóstico , Malformações Vasculares/patologiaRESUMO
PURPOSE: This retrospective study aimed to determine the feasibility, accuracy, and recurrence rates of lymphoscintigraphy and the new sentinel lymph node biopsy (SLNB) for patients with ipsilateral breast tumor recurrences who were treated previously with conservative surgery and had negative SLNB results. METHODS: The study was conducted at the European Institute of Oncology in Milan and included 212 patients with the diagnosis of operable local breast cancer recurrence. They had been treated previously with conservative surgery and showed negative SLNB results. They subsequently underwent additional breast surgery and a second SLNB between May 2001 and December 2011. RESULTS: Preoperative lymphoscintigraphy demonstrated at least one new axillary sentinel lymph node (SLN) in 207 patients (97.7 %), whereas no drainage was observed in five patients (2.3 %). One or more SLNs were surgically removed from 196 of the 207 patients. Isolation of SLNs from the remaining 11 patients could not be accomplished. The success rate for the SLNB was 92.5 %. Extra-axillary drainage pathways were visualized in 17 patients (8 %). The annual axillary recurrence rate after a median follow-up period of 48 months was 0.8 %, and the cumulative incidence of axillary recurrence at 5 years was 3.9 %. CONCLUSIONS: A second SLNB should be considered for patients with operable local breast tumor recurrence who underwent conservative surgery and had negative SLNB results. The procedure is technically feasible and accurate for selected patients.
Assuntos
Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/cirurgia , Mastectomia/efeitos adversos , Recidiva Local de Neoplasia/epidemiologia , Biópsia de Linfonodo Sentinela , Axila , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/mortalidade , Carcinoma Lobular/patologia , Europa (Continente)/epidemiologia , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Incidência , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática , Linfocintigrafia , Gradação de Tumores , Invasividade Neoplásica , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
Atypical vascular lesions (AVL) that occur in the field of prior radiation therapy for breast carcinoma are placed within the differential diagnosis with low grade angiosarcoma and other benign vascular lesions. Although considered a benign entity, the exact biological behavior of AVLs is not fully established because of the small number of cases reported in the literature. We aim to further characterize these lesions clinically and histopathologically, and to study their behavior. We report a series of 30 patients with AVL of the breast occurring after radiation exposure, diagnosed and treated at the European Institute of Oncology, Italy. Immunohistochemical study was performed in all cases, using CD31, D2-40, CD105, and Ki-67 antibodies. Twenty-seven patients were treated with standard doses of conventional adjuvant radiation therapy for the prior breast carcinoma. Three patients were treated with intraoperative radiotherapy with electrons. The post-radiation latency interval from breast carcinoma to AVL was 48.5 months (ranged from 1 to 146 months). Most of the lesions were classified as lymphatic type (78.6 %) based on D2-40 positivity. No extension into subcutaneous tissue or significant atypia was noted in all cases. Despite the fact that the AVL of our series have shown benign behavior in 93.3 %, one patient developed local recurrence of AVL, and two cases progressed to angiosarcoma at the previous AVL site. Further studies should be conducted to better understand the clinical behavior and to propose additional histopathologic diagnostic criteria to distinguish AVL from low grade angiosarcoma and those AVL with increased risk for malignant progression. Concerning current treatments of AVL, we recommend complete excision with free surgical margins and close follow up.
Assuntos
Neoplasias da Mama/patologia , Hemangiossarcoma/etiologia , Hemangiossarcoma/patologia , Adulto , Idoso , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/radioterapia , Feminino , Seguimentos , Hemangiossarcoma/diagnóstico , Hemangiossarcoma/metabolismo , Hemangiossarcoma/cirurgia , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação , Radioterapia/efeitos adversos , Resultado do TratamentoRESUMO
The aim of this study was to identify the prognostic factors associated with the risk of loco-regional recurrence (LRR) of women undergoing mastectomy and complete axillary dissection without radiotherapy. We analyzed data from 650 women operated between 1997 and 2001 in a single institution. Median follow-up was 10 years. Overall survival was 89.8 % at 5 years and 76.6 % at 10 years. The 10-year cumulative incidence of LRRs was 10.0 % (5.0, 10.5, 15.8, and 18.5 % in patients with 0, 1-3, 4-9, and ≥10 positive lymph nodes (LNs), respectively). Sixty-two (9.5 %) LRRs were observed, 5 (0.8 %) of which occurred in the axillary LNs. Supraclavicular LNs recurrences (n = 16, 2.5 %) occurred more frequently in patients with four or more positive LNs, Ki-67 ≥ 20 % or extensive peritumoral vascular invasion (PVI). At multivariable analysis, nodal status was the only prognostic factor for local events, while nodal status, Ki-67 and PVI were significant prognostic factors for recurrences in the regional LNs. Moreover, within each category of positive LNs, high values of Ki-67 and extensive PVI were associated with the highest risk of LRR while low values of Ki-67 and absence of extensive PVI were associated with the lowest risk of LRR. Women with node-negative tumors have the lowest risk of LRR and represent the group of patients that might benefit the least from radiotherapy. PVI and Ki-67 might help tailoring PMRT indications among patients with positive LNs. Finally, the very low incidence of recurrences in the axillary LNs raises questions about the inclusion of the axilla in the radiation field.
Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/cirurgia , Mastectomia , Recidiva Local de Neoplasia , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila/patologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/mortalidade , Feminino , Seguimentos , Humanos , Incidência , Excisão de Linfonodo , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/mortalidade , Estadiamento de Neoplasias , Prognóstico , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: In the case of ipsilateral breast tumour recurrence (IBTR) after breast-conserving surgery (BCS), a second conservative surgical approach maybe considered in some motivated patients whereas in others mastectomy is unavoidable. PATIENTS AND METHODS: From 1997 to 2004, 282 patients presented at the European Institute of Oncology with an operable invasive IBTR after BCS. One hundred and sixty-one (57%) underwent a second conservative surgery, whereas 121 patients (43%) were given a mastectomy and represent the study population. We investigated the prognosis and determined predictive factors of outcome. RESULTS: Median time from primary breast cancer to IBTR was 41 months (range 5-213). Recurrences were T2-T4 and/or multifocal in 83 cases (68.6%). With a median follow-up of 5 years after mastectomy, 5-year overall survival (OS) and disease-free survival (DFS) were 73.3% [95% confidence interval (CI) 65.0% to 81.6%] and 50.4% (95% CI 40.9% to 59.8%), respectively. At the multivariate analysis, early onset of IBTR, presence of vascular invasion and Ki67 >or=20 of the recurrent tumour were found to significantly affect both DFS and OS. CONCLUSIONS: In women who need mastectomy for IBTR, early onset of the relapse, high proliferation index and presence of vascular invasion represent the worst prognostic factors.
Assuntos
Neoplasias da Mama/cirurgia , Mastectomia , Recidiva Local de Neoplasia/cirurgia , Adulto , Idoso , Feminino , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Falha de Tratamento , Resultado do TratamentoRESUMO
BACKGROUND: This study was conceived to evaluate the effect of internal thoracic artery (ITA) skeletonization on vessel wall integrity. METHODS: Forty consecutive patients undergoing coronary artery bypass were randomized to receive a skeletonized (n = 22) or a pedicled (n = 18) ITA graft. ITA harvesting was performed by 2 experienced surgeons using the same instrumentation and technique. Specimens were examined by light and electron microscope in order to assess vascular wall integrity. A specific immunohistochemical staining and a computerized method were used to quantify the degree of endothelial integrity after surgical preparation. RESULTS: Morphologic analysis revealed 2 cases of limited subadventitial hemorrhage (one for each group) and no case of major arterial damage. Immunohistochemical staining demonstrated an extremely high degree of maintenance of the endothelial integrity in both groups (97.2% +/- 1.9% in the skeletonized and 96.8% +/- 2.1% in the pedicled one; p = 0.53). CONCLUSIONS: Skeletonization does not affect ITA wall integrity in humans submitted to coronary artery bypass procedures.
Assuntos
Doença das Coronárias/cirurgia , Artéria Torácica Interna/patologia , Revascularização Miocárdica/métodos , Idoso , Doença das Coronárias/patologia , Endotélio Vascular/patologia , Feminino , Sobrevivência de Enxerto/fisiologia , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Complicações Pós-Operatórias/patologiaRESUMO
In the bipolar neurons of vertebrate cochlear and vestibular nerves, the myelin envelopes without interruption the axon, the perikaryon and the dendrite. The perikaryal myelin is thin and partially loose, whereas axon and dendrite are enveloped by compacted myelin. The expression of protein 0 and myelin basic protein, constituents of peripheral and central myelin respectively, has been investigated in the rat by immunohistochemical study at the light microscopic level. Our data indicate that both in the cochlear and vestibular nerves the myelin of the perikaryon and dendrite is composed by specific peripheral myelin proteins. The axon segment between the perikaryon and the transitional zone expresses peripheral myelin proteins in the cochlear nerve, while both types of myelin proteins are present in the vestibular nerve. Between the transitional zone and the brainstem the myelin of the axon is exclusively of the central type. The peripheral-central myelin transitional zone is in close proximity to the axonal pole in the vestibular ganglion cells, while in the cochlear nerve it is near the spiral foramina, at variable distance from the axonal pole of ganglion cells.
Assuntos
Nervo Coclear/química , Proteína Básica da Mielina/análise , Proteína P0 da Mielina/análise , Nervo Vestibular/química , Animais , Especificidade de Anticorpos , Nervo Coclear/citologia , Dendritos/química , Imunofluorescência , Gânglios Sensitivos/química , Gânglios Sensitivos/citologia , Proteína Básica da Mielina/imunologia , Proteína P0 da Mielina/imunologia , Bainha de Mielina/química , Neurônios/química , Ratos , Ratos Wistar , Nervo Vestibular/citologiaRESUMO
To investigate the pathogenesis of the degenerative changes of the ligamentum flavum occurring in lumbar spine stenosis, yellow ligament cells from patients with lumbar spine stenosis were cultured for the first time and subjected to biochemical, histochemical and immunohistochemical study. Stenotic ligamentum flavum (SLF) cells were seen to express high levels of alkaline phosphatase (ALP) activity and to produce a matrix rich in type I and III collagen, fibronectin and osteonectin. The matrix mineralized only following beta-glycerophosphate (betaGP) and ascorbic acid supplementation. Stimulation with human parathyroid hormone (PTH) increased intracellular cAMP concentration. These findings indicate that there was significant evidence of osteoblast-like activity in these cells. SLF cells also stained for S100 protein, type II and type X collagen, and co-localized type II collagen and ALP labelling, reflecting the presence of hypertrophic chondrocyte-like cells. Cultures from control patients showed neither osteoblastic nor chondrocytic features: they expressed type I and type III collagen and fibronectin, but did not stain for osteonectin, nor were bone-like calcifications observed in presence or absence of betaGP. Normal ligamentum flavum (NLF) cells did not synthesized S100 protein or type II or type X collagen, and showed a weaker response to PTH stimulation. Our data demonstrated the presence of hypertrophic chondrocytes with an osteoblast-like activity in the ligamentum flavum of patients with spinal stenosis suggesting that they could have a role in the pathophysiology of the heterotopic ossification of ligamentum flavum (OLF) in lumbar spine stenosis.
Assuntos
Ligamento Amarelo/patologia , Estenose Espinal/patologia , Fosfatase Alcalina/metabolismo , Matriz Óssea/metabolismo , Células Cultivadas , Colágeno/metabolismo , AMP Cíclico/metabolismo , Fibronectinas/metabolismo , Humanos , Imuno-Histoquímica , Ligamento Amarelo/efeitos dos fármacos , Ligamento Amarelo/metabolismo , Região Lombossacral , Pessoa de Meia-Idade , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteonectina/metabolismo , Hormônio Paratireóideo/farmacologia , Valores de Referência , Proteínas S100/metabolismo , Fraturas da Coluna Vertebral/metabolismo , Fraturas da Coluna Vertebral/patologia , Estenose Espinal/metabolismoRESUMO
Nerve growth factor (NGF) exerts its action through two types of receptor: high-affinity tyrosine kinase A receptor (trkA) and low-affinity p75 receptor. NGF has a neurotrophic role in central and peripheral nervous system development, but there is also clear evidence of its involvement in the developing skeleton. The aim of the present immunohistochemical study was to investigate the expression and distribution of NGF, trkA, and p75 in normal cartilaginous tissues from adult subjects: articular and meniscal cartilage of the knee, cartilage from the epiglottis, and intervertebral disc tissue. Detection of NGF mRNA was also performed by in situ hybridization. Immunoreaction for NGF and the two receptors in articular chondrocytes, chondrocyte-like cells of meniscus and annulus fibrosus, and chondrocytes of the epiglottis demonstrated that they are all expressed in hyaline, fibrous and elastic cartilaginous tissues, suggesting that they could be involved in cartilage physio-pathology.
Assuntos
Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Fator de Crescimento Neural/metabolismo , Receptor de Fator de Crescimento Neural/metabolismo , Receptor trkA/metabolismo , Adulto , Cartilagem Articular/citologia , Condrócitos/citologia , Humanos , Técnicas Imunoenzimáticas , Hibridização In Situ , Pessoa de Meia-Idade , Fator de Crescimento Neural/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
AIMS: The aim of this study was to assess concordance between the indocyanine green (ICG) method and (99m)Tc-radiotracer method to identify the sentinel node (SN) in breast cancer. Evidence supports the feasibility and efficacy of the ICG to identify the SN, however this method has not been prospectively compared with the gold-standard radiotracer method in terms of SN detection rate. METHODS: Between June 2011 and January 2013, 134 women with clinically node-negative early breast cancer received subdermal/peritumoral injection of (99m)Tc-labeled tracer for lymphoscintigraphy, followed by intraoperative injection of ICG for fluorescence detection of SNs using an exciting light source combined with a camera. In all patients, SNs were first identified by the fluorescence method (ICG-positive) and removed. A gamma ray-detecting probe was then used to determine whether ICG-positive SNs were hot ((99m)Tc-positive) and to identify and remove any (99m)Tc-positive (ICG-negative) SNs remaining in the axilla. The study was powered to perform an equivalence analysis. RESULTS: The 134 patients provided 246 SNs, detected by one or both methods. 1, 2 and 3 SNs, respectively, were detected, removed and examined in 70 (52.2%), 39 (29.1%) and 17 (12.7%) patients; 4-10 SNs were detected and examined in the remaining 8 patients. The two methods were concordant for 230/246 (93.5%) SNs and discordant for 16 (6.5%) SNs. The ICG method detected 99.6% of all SNs. CONCLUSIONS: Fluorescent lymphangiography with ICG allows easy identification of axillary SNs, at a frequency not inferior to that of radiotracer, and can be used alone to reliably identify SNs.
Assuntos
Neoplasias da Mama/patologia , Corantes , Verde de Indocianina , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Biópsia de Linfonodo Sentinela/métodos , Tecnécio , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Neoplasias da Mama/cirurgia , Feminino , Fluorescência , Humanos , Metástase Linfática , Linfografia , Pessoa de Meia-Idade , CintilografiaRESUMO
Lamins are the major proteic constituents of the nuclear lamina, the innermost layer of the nuclear membrane. The immunolocalization of lamins in the rat central nervous system was studied using polyclonal antibodies. Besides an ubiquitarious localization in the nuclear membranes of neurons and glial cells, an intense lamin-like immunoreactivity was found in the soma and dendrites of cerebellar Purkinje cells. The same specific reaction was also observed in the human cerebellum. Experiments performed in newborn animals demonstrated that the cytoplasmic expression of lamins in Purkinje cells begins during postnatal development.
Assuntos
Química Encefálica , Proteínas Nucleares/análise , Células de Purkinje/química , Medula Espinal/química , Animais , Cerebelo/química , Cerebelo/crescimento & desenvolvimento , Citoplasma/química , Dendritos/química , Humanos , Técnicas Imunoenzimáticas , Laminas , Masculino , Pessoa de Meia-Idade , Neuroglia/química , Neurônios/química , Membrana Nuclear/química , Proteínas Nucleares/imunologia , Células de Purkinje/ultraestrutura , Ratos , Ratos EndogâmicosRESUMO
Osteoblast-like cells isolated from human bone bioptic specimens were established in culture. Their osteoblast-like phenotype was studied by biochemical, histochemical and immunohistochemical methods and by electron microscopy examination. Third-passage cell cultures exhibited high level of alkaline phosphatase activity and the exposure to human parathyroid hormone produced an increase of intracellular cAMP. Cultured cells were immunoreactive for type I and type III collagen, osteonectin, and fibronectin; when ascorbic acid and beta-glycerophosphate were added, they synthesized a rich extracellular matrix. This characterization ensures the reliability of osteoblast-like cultures when they are used as experimental models.
Assuntos
Células Cultivadas , Osteoblastos , Adulto , Fosfatase Alcalina/análise , Ácido Ascórbico/farmacologia , Matriz Óssea/metabolismo , Colágeno/análise , AMP Cíclico/metabolismo , Fibronectinas/análise , Glicerofosfatos/farmacologia , Histocitoquímica , Humanos , Imuno-Histoquímica , Microscopia Eletrônica de Varredura , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoblastos/ultraestrutura , Osteonectina/análise , Hormônio Paratireóideo/farmacologiaRESUMO
Osteoblast-like cells isolated from human bone bioptic specimens were characterized and analysed for the presence of type II estrogen receptor (type II EBS). The amount of type II EBS was measured by a whole-cell assay at 4 degrees C for 2.5 h using [(3)H]-estradiol as tracer. Saturation analysis, used to investigate the binding characteristic of type II EBS, resulted in a sigmoid curve. Scatchard analysis showed the binding affinity of the estrogen receptor, yielding a concave plot. The dissociation constant (K(d)), determined from the [(3)H]-estradiol concentration required for half saturation was about 12+/-2 nM (SD). The number of type II EBS, estimated at maximum binding, was 197,000+/-8800 sites per cell. If the regulation of the receptor by flavonoids would be confirmed, the evidence of type II EBS in osteoblast-like cells could suggest a direct action of ipriflavone and others flavonoids on bone density in postmenopausal osteoporosis.
Assuntos
Osso e Ossos/metabolismo , Osteoblastos/metabolismo , Receptores de Estrogênio/metabolismo , Adulto , Fosfatase Alcalina/metabolismo , Ligação Competitiva/efeitos dos fármacos , Osso e Ossos/citologia , Osso e Ossos/efeitos dos fármacos , Células Cultivadas , Colágeno/metabolismo , AMP Cíclico/metabolismo , Citoplasma/enzimologia , Estradiol/farmacocinética , Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Humanos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteonectina/metabolismo , Hormônio Paratireóideo/farmacologia , Quercetina/farmacocinética , Especificidade por Substrato/efeitos dos fármacos , TrítioRESUMO
The microarchitecture of the corpora cavernosa of the human clitoris was investigated by immunohistochemistry. The distribution pattern of the nerve network was demonstrated by S-100 and neuron specific enolase immunoreactivity. Vascular and nonvascular muscle cells were identified by desmin and/or vimentin expression, and fibroblasts and endothelial cells by vimentin immunoreactivity. The findings show that tissue organisation in the corpora cavernosa of the clitoris is essentially similar to that of the penis except for the absence of the subalbugineal layer interposed between the tunica albuginea and erectile tissue. This has functional implications, suggesting that the clitoral erection cycle differs from that of the penis.
Assuntos
Clitóris/anatomia & histologia , Adulto , Clitóris/química , Clitóris/inervação , Desmina/análise , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Fibras Nervosas/química , Fibras Nervosas/ultraestrutura , Fosfopiruvato Hidratase/análise , Proteínas S100/análise , Vimentina/análiseRESUMO
An electron microscopic study of 4 solitary schwannomas and 2 neurofibromas of peripheral nerves was performed with the aim of investigating the debated histogenesis of the two types of lesion. Our observations confirm that solitary schwannoma is composed almost exclusively of cells with characteristics of differentiated Schwann cells, thus providing evidence for a neuroectodermal origin of the tumor. Analysis of the ultrastructure of neurofibroma shows the presence of 3 different types of cells: Schwann-like cells, perineurial-like cells, and fibroblast-like cells. Perineurial-like cells were prevalent in our observations. These findings as well as the many controversial aspects of the origin of neurofibroma could be explained by separating this type of neoplasia into two pathological forms: perineurial and interstitial. Moreover, the numerous differences between solitary schwannoma and neurofibroma allow us to hypothesize a different cellular origin for each tumor. If confirmed by further observations, this would explain the difference in the capacity of the two types of neoplasia to undergo malignant change, an occurrence almost unknown in solitary schwannoma yet relatively common in neurofibroma.
Assuntos
Neurilemoma/ultraestrutura , Neurofibroma/ultraestrutura , Neoplasias do Sistema Nervoso Periférico/ultraestrutura , Colágeno/ultraestrutura , Tecido Conjuntivo/patologia , Tecido Conjuntivo/ultraestrutura , Fibroblastos , Humanos , Hiperplasia , Microscopia Eletrônica , Neurilemoma/etiologia , Neurilemoma/patologia , Neurofibroma/etiologia , Neurofibroma/patologia , Neoplasias do Sistema Nervoso Periférico/etiologia , Neoplasias do Sistema Nervoso Periférico/patologia , Células de Schwann/ultraestruturaRESUMO
The occurrence and distribution of neuropeptide Y in the human clitoris and penis was investigated by light immunohistochemistry. Neuropeptide Y-containing nerve fibers were detected in the tunicae of arteries and veins as well as among trabecular smooth muscle. The distribution pattern of the peptide was similar in both organs although a higher density of immunoreactive nerve fibers was detected in the penis. The immunolocalization of neuropeptide Y was also compared with that of neuron-specific enolase, a neuronal marker which labels the entire nerve network. It is suggested that neuropeptide Y is involved in the physiology of the penis and the clitoris, affecting vascular and nonvascular smooth muscle activity.
Assuntos
Clitóris/inervação , Neuropeptídeo Y/análise , Pênis/inervação , Adolescente , Adulto , Biomarcadores , Clitóris/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Liso/inervação , Proteínas do Tecido Nervoso/análise , Pênis/química , Fosfopiruvato Hidratase/análiseRESUMO
The axon regeneration following a peripheral nerve injury often fails to restore a complete functional recovery. One of the causes of this unsatisfactory result has been attributed to regrowth of regenerating fibers to inappropriate peripheral targets. The accuracy of reinnervation by axons regenerating across a 10-mm gap within an impermeable chamber has been studied by using a sequential retrograde double-labeling technique. Despite the long gap between the nerve stumps, at 4 weeks a mean of 30.5% of the regenerating axons can reinnervate the original muscular area. These data confirm previous studies in which a preferential reinnervation is reported not to be absolutely dependent on the axon's mechanical alignment.
Assuntos
Axônios/fisiologia , Músculos/inervação , Regeneração Nervosa , Nervo Isquiático/fisiologia , Potenciais de Ação , Animais , Transporte Axonal , Axônios/ultraestrutura , Feminino , Placa Motora/fisiologia , Placa Motora/ultraestrutura , Neurônios Motores/citologia , Neurônios Motores/fisiologia , Bainha de Mielina/fisiologia , Bainha de Mielina/ultraestrutura , Permeabilidade , Ratos , Ratos EndogâmicosRESUMO
Ultrastructural analysis was conducted on samples of articular cartilage taken from both load-bearing and non-load-bearing areas with the aim of evaluating the morphologic adaptation of the articular cartilage to mechanical stimulation and identifying the mechanisms of interaction of the chondrocyte and the matrix. Through this analysis we were able to better define the adaptation process of the cartilage as well as the modalities of mechanical stress transmission. We believe that the complex formed by the chondrocyte, the pericellular matrix, and the pericellular capsule constitutes the biomechanical unit of the articular cartilage which serves as the sensor and transducer of mechanical stress. The arrangement of the collagen fibers and the proteoglycans which make up the pericellular capsule and membrane around the chondrocyte can be compared, from a mechanical standpoint, to a dynamic structure constructed in order to absorb the load stresses and protect the internal environment. From a biological standpoint, these are comparable to an extracellular-scaffold constructed with the aim of mediating the interaction between the chondrocyte and the territorial and inter-territorial compartments.
Assuntos
Cartilagem Articular/ultraestrutura , Adaptação Fisiológica , Animais , Cartilagem Articular/fisiologia , Matriz Extracelular/ultraestrutura , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Coelhos , Estresse MecânicoRESUMO
The authors analyze the ultrastructure of mast cells and perineurial cells when both are present in neurofibroma of the nerve sheath. Samples of pathologic tissue taken from three patients with neurofibroma of a peripheral nerve sheath were analyzed by light and transmission electron microscopy. The observations document the characteristics of the tumor cells (Schwann cells and perineurial cells) as well as the presence of numerous mast cells, typically in close contact with the perineurial cells and never with the Schwann cells. Many electron-dense vesicles were found between the cells; these vesicles are created when the cell membrane of the mast cell buds, and then they come into contact with the adjacent perineurial cell. Endocytosis vesicles are often present in the cytoplasm of perineurial cells. Analysis of these observations led the authors to assume the existence of a metabolic interaction between the two cell type in contact with each other and an active role of the mast cells in the evolution of the tumor. The following two theories are plausible: either the mast cells actively stimulate tumor growth, or they alter the phenotype of the tumor cell. These findings could have interesting clinical applications. The use of treatment protocols which inhibit mast cell activity could, in theory, stop either the proliferation of the neurofibroma or its malignant transformation.
Assuntos
Mastócitos/ultraestrutura , Neurofibroma/ultraestrutura , Neoplasias do Sistema Nervoso Periférico/ultraestrutura , Divisão Celular , Humanos , Mastócitos/fisiologia , Microscopia Eletrônica , Neurofibroma/patologia , Neoplasias do Sistema Nervoso Periférico/patologia , Células de Schwann/ultraestruturaRESUMO
Skeletal muscle denervation leads to an increase of proteolytic activity, which is also favoured by reduced levels of alpha1 antichymotrypsin and nexin II, two serine-proteinase inhibitors normally acting at the neuromuscular junction. In the present experiments we extended our investigation to other muscular proteinase inhibitors after denervation. In all muscles examined (soleus, plantaris, extensor digitorum longus) specific immunoreactivity for alpha2macroglobulin (alpha2M) and alpha1proteinase inhibitor (alpha-1-antitrypsin, ATI) was distributed in peri-endomysial structures as well as in small patches inside the fibres. By contrast, inter-alpha-trypsin inhibitor (ITI) was mainly localized in the extracellular matrix. These localization patterns did not change substantially in 15-days denervated muscles. Dot-blot analysis revealed a small decrease (about 15%) of alpha2M in 15-days denervated muscles, while ATI and ITI specific activities were substantially unchanged. RT-PCR allowed us to detect the above protease inhibitor mRNAs in normal muscle homogenates. Denervation atrophy induced by section of the sciatic nerve resulted in a remarkable reduction of (2macroglobulin mRNA (60%) and ITI (30%), but not ATI, as measured by computer-assisted semiquantitative densitometry of electrophoresed RT-PCR bands. The marked decrease of alpha2M we have detected in denervated muscle may be responsible, at least in part, for the proteolytic increase which is known to occur in skeletal muscle during denervation atrophy.