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1.
Sci Rep ; 11(1): 20653, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34667213

RESUMO

Non-syndromic inherited defects of tooth dentin are caused by two classes of dominant negative/gain-of-function mutations in dentin sialophosphoprotein (DSPP): 5' mutations affecting an N-terminal targeting sequence and 3' mutations that shift translation into the - 1 reading frame. DSPP defects cause an overlapping spectrum of phenotypes classified as dentin dysplasia type II and dentinogenesis imperfecta types II and III. Using CRISPR/Cas9, we generated a Dspp-1fs mouse model by introducing a FLAG-tag followed by a single nucleotide deletion that translated 493 extraneous amino acids before termination. Developing incisors and/or molars from this mouse and a DsppP19L mouse were characterized by morphological assessment, bSEM, nanohardness testing, histological analysis, in situ hybridization and immunohistochemistry. DsppP19L dentin contained dentinal tubules but grew slowly and was softer and less mineralized than the wild-type. DsppP19L incisor enamel was softer than normal, while molar enamel showed reduced rod/interrod definition. Dspp-1fs dentin formation was analogous to reparative dentin: it lacked dentinal tubules, contained cellular debris, and was significantly softer and thinner than Dspp+/+ and DsppP19L dentin. The Dspp-1fs incisor enamel appeared normal and was comparable to the wild-type in hardness. We conclude that 5' and 3' Dspp mutations cause dental malformations through different pathological mechanisms and can be regarded as distinct disorders.


Assuntos
Dentinogênese Imperfeita/genética , Proteínas da Matriz Extracelular/genética , Fosfoproteínas/genética , Sialoglicoproteínas/genética , Animais , Esmalte Dentário/metabolismo , Dentina/metabolismo , Dentinogênese Imperfeita/metabolismo , Dentinogênese Imperfeita/fisiopatologia , Modelos Animais de Doenças , Proteínas da Matriz Extracelular/metabolismo , Feminino , Mutação da Fase de Leitura/genética , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Fenótipo , Fosfoproteínas/metabolismo , Sialoglicoproteínas/metabolismo , Dente/metabolismo
2.
BMC Vet Res ; 13(1): 32, 2017 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-28118835

RESUMO

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs), transdermal fentanyl patches, and transmucosal buprenorphine are probably the most commonly used options for providing post-operative analgesia in the early at-home period. However, these require daily administration or are associated with abuse concerns. One of the significant unmet needs in veterinary surgery and pain management is for longer acting opioids for cats to effectively bridge the gap between the in-hospital and at-home recovery periods. A proof of concept study of an extended release formulation of buprenorphine HCL (ER-Bup) was conducted using objective kinetic measures and a unilateral onychectomy model. Using a blinded, randomized, two period crossover design, four cats were allocated to control (saline) or ER-Bup (0.6 mg/kg, subcutaneously [SC]) treatment groups. All animals underwent a unilateral forelimb onychectomy per period with a washout/recovery period in between. Observational pain scores and kinetic data (using a pressure sensitive walkway [PSW]) were collected prior to (baseline) and at intervals for 72 h following surgery. Symmetry indices were derived for kinetic variables (peak vertical force [PVF]; vertical impulse [VI]) of each forelimb for landing following a jump and for walking. A rescue analgesic protocol was in place. Effect of surgery and treatment were evaluated using a mixed model statistical approach. RESULTS: No cats required rescue analgesics based on subjective pain score. ER-Bup had a positive influence on subjective pain scores during the 72 h postsurgery (p = 0.0473). PVF and VI of the operated limb were significantly decreased for both landing (p < 0.0001 and p < 0.0001) and walking (p < 0.0001 and p < 0.0001 respectively) compared to control. ER-Bup resulted in significantly decreased asymmetry in limb use during landing (PVF, p < 0.0001; VI, p < 0.0001) and walking (PVF, p = 0.0002, VI, p < 0.0001). The novel use of data collected following a jump from an elevated platform appeared to provide all desired information and was easier to collect than walking data. CONCLUSION: This study demonstrates that SC administration of ER-Bup may be an effective analgesic for a 72 h period postoperatively. Furthermore, landing onto a PSW from an elevated perch may be a useful and efficient way to assess analgesics in cats using a unilateral model of limb pain.


Assuntos
Analgésicos Opioides/uso terapêutico , Buprenorfina/uso terapêutico , Gatos/cirurgia , Casco e Garras/cirurgia , Procedimentos Ortopédicos/veterinária , Dor Pós-Operatória/veterinária , Analgésicos Opioides/administração & dosagem , Animais , Buprenorfina/administração & dosagem , Preparações de Ação Retardada , Feminino , Masculino , Atividade Motora , Medição da Dor/métodos , Medição da Dor/veterinária , Dor Pós-Operatória/tratamento farmacológico , Projetos Piloto
3.
J Trauma Acute Care Surg ; 81(5): 936-951, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27533913

RESUMO

INTRODUCTION: Thoracic trauma is the second most prevalent nonintentional injury in the United States and is associated with significant morbidity. Analgesia for blunt thoracic trauma was first addressed by the Eastern Association for the Surgery of Trauma (EAST) with a practice management guideline published in 2005. Since that time, it was hypothesized that there have been advances in the analgesic management for blunt thoracic trauma. As a result, updated guidelines for this topic using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) framework recently adopted by EAST are presented. METHODS: Five systematic reviews were conducted using multiple databases. The search retrieved articles regarding analgesia for blunt thoracic trauma from January1967 to August 2015. Critical outcomes of interest were analgesia, postoperative pulmonary complications, changes in pulmonary function tests, need for endotracheal intubation, and mortality. Important outcomes of interest examined included hospital and intensive care unit length of stay. RESULTS: Seventy articles were identified. Of these, 28 articles were selected to construct the guidelines. The overall risk of bias for all studies was high. The majority of included studies examined epidural analgesia. Epidural analgesia was associated with lower short-term pain scores in most studies, but the quality and quantity of evidence were very low, and no firm evidence of benefit or harm was found when this modality was compared with other analgesic interventions. The quality of evidence for paravertebral block, intrapleural analgesia, multimodal analgesia, and intercostal nerve blocks was very low as assessed by GRADE. The limitations with the available literature precluded the formulation of strong recommendations by our panel. CONCLUSION: We propose two evidence-based recommendations regarding analgesia for patients with blunt thoracic trauma. The overall risk of bias for all studies was high. The limitations with the available literature precluded the formulation of strong recommendations by our panel. We conditionally recommend epidural analgesia and multimodal analgesia as options for patients with blunt thoracic trauma, but the overall quality of evidence supporting these modalities is low in trauma patients. These recommendations are based on very low-quality evidence but place a high value on patient preferences for analgesia. These recommendations are in contradistinction to the previously published Practice Management Guideline published by EAST.


Assuntos
Analgesia Epidural , Analgesia/métodos , Manejo da Dor/métodos , Traumatismos Torácicos/complicações , Ferimentos não Penetrantes/complicações , Adulto , Medicina Baseada em Evidências , Humanos , Dor/etiologia , Medição da Dor , Traumatismos Torácicos/terapia , Ferimentos não Penetrantes/terapia
4.
J Orthop Surg Res ; 10: 155, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26429572

RESUMO

BACKGROUND: Our group developed a protocol, entitled Early Appropriate Care (EAC), to determine timing of definitive fracture fixation based on presence and severity of metabolic acidosis. We hypothesized that utilization of EAC would result in fewer complications than a historical cohort and that EAC patients with definitive fixation within 36 h would have fewer complications than those treated at a later time. METHODS: Three hundred thirty-five patients with mean age 39.2 years and mean Injury Severity Score (ISS) 26.9 and 380 fractures of the femur (n = 173), pelvic ring (n = 71), acetabulum (n = 57), and/or spine (n = 79) were prospectively evaluated. The EAC protocol recommended definitive fixation within 36 h if lactate <4.0 mmol/L, pH ≥7.25, or base excess (BE) ≥-5.5 mmol/L. Complications including infections, sepsis, DVT, organ failure, pneumonia, acute respiratory distress syndrome (ARDS), and pulmonary embolism (PE) were identified and compared for early and delayed patients and with a historical cohort. RESULTS: All 335 patients achieved the desired level of resuscitation within 36 h of injury. Two hundred sixty-nine (80%) were treated within 36 h, and 66 had protocol violations, treated on a delayed basis, due to surgeon choice in 71%. Complications occurred in 16.3% of patients fixed within 36 h and in 33.3% of delayed patients (p = 0.0009). Hospital and ICU stays were shorter in the early group: 9.5 versus 17.3 days and 4.4 versus 11.6 days, respectively, both p < 0.0001. This group of patients when compared with a historical cohort of 1443 similar patients with 1745 fractures had fewer complications (16.3 versus 22.1%, p = 0.017) and shorter length of stay (LOS) (p = 0.018). CONCLUSIONS: Our EAC protocol recommends definitive fixation within 36 h in resuscitated patients. Early fixation was associated with fewer complications and shorter LOS. The EAC recommendations are safe and effective for the majority of severely injured patients with mechanically unstable femur, pelvis, acetabular, or spine fractures requiring fixation.


Assuntos
Protocolos Clínicos , Fixação de Fratura/efeitos adversos , Fraturas Ósseas/cirurgia , Ressuscitação/métodos , Acidose/etiologia , Acidose/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fixação de Fratura/métodos , Fixação de Fratura/normas , Fraturas Ósseas/complicações , Humanos , Escala de Gravidade do Ferimento , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/complicações , Traumatismo Múltiplo/cirurgia , Complicações Pós-Operatórias , Prognóstico , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
5.
J Orthop Trauma ; 29(11): e446-50, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26165260

RESUMO

OBJECTIVES: We developed a protocol to determine the timing of definitive fracture care based on the adequacy of resuscitation. Inception of this project required a multidisciplinary group, including physicians from anesthesiology, general trauma and critical care, neurosurgery, orthopaedic spine, and orthopaedic trauma. The purposes of this study were to review our initial experience with adherence to protocol recommendations and to assess barriers to implementation. DESIGN: Prospective. SETTING: Level 1 trauma center. INTERVENTION: Definitive fixation of pelvis, acetabulum, spine, and femur fractures within 36 hours of injury, based on laboratory parameters for acidosis. MAIN OUTCOME MEASUREMENTS: Three hundred five consecutive skeletally mature patients with Injury Severity Score ≥ 16 (mean, 26.4) and 346 fractures of the proximal or diaphyseal femur (n = 152), pelvic ring (n = 56), acetabulum (n = 44), and/or spine (n = 94) were treated surgically. Adherence to the protocol was defined as definitive fixation within 36 hours of injury in resuscitated patients. All patients were adequately resuscitated within that time. Patient demographic and injury characteristics, date and time of presentation, and reasons for delay were recorded. RESULTS: Two hundred fifty-one patients (82%) with 287 fractures were treated according to the protocol, whereas 54 patients (18%) with 59 fractures were definitively stabilized on a delayed basis (mean, 90 hours). Delay was not related to patient age, Injury Severity Score, day of week, or time of presentation. Before implementation of this protocol, 76% were treated on a delayed basis, demonstrating improvement for each fracture type: spine (79% of previous patients with delay), pelvis (57%), acetabulum (72%), and femur (22%); all P < 0.0001 for more frequently delayed surgery before the protocol. Surgeon choice to delay the procedure accounted for 67% of reasons for delay. Other reasons included intensivist choice (13%), operating room availability (7.4%), patient choice (3.7%), severe head injury (5.6%), or cardiac issues (3.7%). Our trauma center and surgeons became more accustomed to the protocol and had fewer delays over time; 10% were delayed 2 years after implementation. CONCLUSIONS: Management of trauma patients with injury to multiple systems requires teamwork among providers from related specialties and hospital support, in terms of operating room access, with appropriate ancillary personnel and equipment. Our system adjusted quickly to the protocol. Surgeon preference was the most common reason for delayed fixation, but within 24 months, only 10% of fractures were treated on a delayed basis, as long as patients were resuscitated.


Assuntos
Protocolos Clínicos , Fraturas Ósseas/cirurgia , Traumatismo Múltiplo/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fixação de Fratura , Fraturas Ósseas/terapia , Fidelidade a Diretrizes , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Administração dos Cuidados ao Paciente , Equipe de Assistência ao Paciente , Estudos Prospectivos , Fatores de Tempo , Centros de Traumatologia , Adulto Jovem
6.
Mol Biol Cell ; 26(22): 4015-32, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-25808494

RESUMO

The molecular basis of changes in structure, cellular location, and function of the Golgi apparatus during male germ cell differentiation is unknown. To deduce cognate Golgi proteins, we isolated germ cell Golgi fractions, and 1318 proteins were characterized, with 20 localized in situ. The most abundant protein, GL54D of unknown function, is characterized as a germ cell-specific Golgi-localized type II integral membrane glycoprotein. TM9SF3, also of unknown function, was revealed to be a universal Golgi marker for both somatic and germ cells. During acrosome formation, several Golgi proteins (GBF1, GPP34, GRASP55) localize to both the acrosome and Golgi, while GL54D, TM9SF3, and the Golgi trafficking protein TMED7/p27 are segregated from the acrosome. After acrosome formation, GL54D, TM9SF3, TMED4/p25, and TMED7/p27 continue to mark Golgi identity as it migrates away from the acrosome, while the others (GBF1, GPP34, GRASP55) remain in the acrosome and are progressively lost in later steps of differentiation. Cytoplasmic HSP70.2 and the endoplasmic reticulum luminal protein-folding enzyme PDILT are also Golgi recruited but only during acrosome formation. This resource identifies abundant Golgi proteins that are expressed differentially during mitosis, meiosis, and postacrosome Golgi migration, including the last step of differentiation.


Assuntos
Complexo de Golgi/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo , Acrossomo/metabolismo , Animais , Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Retículo Endoplasmático/metabolismo , Células Hep G2 , Humanos , Masculino , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana , Transporte Proteico , Ratos , Ratos Sprague-Dawley , Espermátides/metabolismo , Espermatogênese
7.
Eur J Oral Sci ; 122(1): 21-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24313748

RESUMO

The sodium pump Na(+)/K(+)-ATPase, expressed in virtually all cells of higher organisms, is involved in establishing a resting membrane potential and in creating a sodium gradient to facilitate a number of membrane-associated transport activities. Na(+)/K(+)-ATPase is an oligomer of α, ß, and γ subunits. Four unique genes encode each of the α and ß subunits. In dental enamel cells, the spatiotemporal expression of Na(+)/K(+)-ATPase is poorly characterized. Using the rat incisor as a model, this study provides a comprehensive expression profile of all four α and all four ß Na(+)/K(+)-ATPase subunits throughout all stages of amelogenesis. Real-time PCR, western blot analysis, and immunolocalization revealed that α1, ß1, and ß3 are expressed in the enamel organ and that all three are most highly expressed during late-maturation-stage amelogenesis. Expression of ß3 was significantly higher than expression of ß1, suggesting that the dominant Na(+)/K(+)-ATPase consists of an α1ß3 dimer. Localization of α1, ß1, and ß3 subunits in ameloblasts was primarily to the cytoplasm and occasionally along the basolateral membranes. Weaker expression was also noted in papillary layer cells during early maturation. Our data support that Na(+)/K(+)-ATPase is functional in maturation-stage ameloblasts.


Assuntos
Órgão do Esmalte/enzimologia , ATPase Trocadora de Sódio-Potássio/genética , Ameloblastos/enzimologia , Amelogênese/genética , Animais , Western Blotting/métodos , Membrana Celular/enzimologia , Citoplasma/enzimologia , Proteínas do Esmalte Dentário/genética , Perfilação da Expressão Gênica/métodos , Incisivo/embriologia , Masculino , Modelos Animais , Multimerização Proteica , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
8.
J Cell Sci ; 126(Pt 3): 732-44, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23264742

RESUMO

Tooth enamel has the highest degree of biomineralization of all vertebrate hard tissues. During the secretory stage of enamel formation, ameloblasts deposit an extracellular matrix that is in direct contact with the ameloblast plasma membrane. Although it is known that integrins mediate cell-matrix adhesion and regulate cell signaling in most cell types, the receptors that regulate ameloblast adhesion and matrix production are not well characterized. We hypothesized that αvß6 integrin is expressed in ameloblasts where it regulates biomineralization of enamel. Human and mouse ameloblasts were found to express both ß6 integrin mRNA and protein. The maxillary incisors of Itgb6(-/-) mice lacked yellow pigment and their mandibular incisors appeared chalky and rounded. Molars of Itgb6(-/-) mice showed signs of reduced mineralization and severe attrition. The mineral-to-protein ratio in the incisors was significantly reduced in Itgb6(-/-) enamel, mimicking hypomineralized amelogenesis imperfecta. Interestingly, amelogenin-rich extracellular matrix abnormally accumulated between the ameloblast layer of Itgb6(-/-) mouse incisors and the forming enamel surface, and also between ameloblasts. This accumulation was related to increased synthesis of amelogenin, rather than to reduced removal of the matrix proteins. This was confirmed in cultured ameloblast-like cells, in which αvß6 integrin was not an endocytosis receptor for amelogenins, although it participated in cell adhesion on this matrix indirectly via endogenously produced matrix proteins. In summary, integrin αvß6 is expressed by ameloblasts and it plays a crucial role in regulating amelogenin deposition and/or turnover and subsequent enamel biomineralization.


Assuntos
Ameloblastos/metabolismo , Amelogênese Imperfeita/metabolismo , Antígenos de Neoplasias/metabolismo , Esmalte Dentário/metabolismo , Integrinas/metabolismo , Atrito Dentário/prevenção & controle , Ameloblastos/patologia , Amelogênese Imperfeita/complicações , Amelogênese Imperfeita/genética , Amelogenina/metabolismo , Animais , Antígenos de Neoplasias/genética , Adesão Celular/genética , Células Cultivadas , Esmalte Dentário/patologia , Matriz Extracelular/metabolismo , Integrinas/genética , Camundongos , Camundongos Knockout , Atrito Dentário/etiologia , Calcificação de Dente/genética , Desmineralização do Dente
9.
J Bone Miner Res ; 28(3): 672-87, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23044750

RESUMO

Molecular events defining enamel matrix removal during amelogenesis are poorly understood. Early reports have suggested that adaptor proteins (AP) participate in ameloblast-mediated endocytosis. Enamel formation involves the secretory and maturation stages, with an increase in resorptive function during the latter. Here, using real-time PCR, we show that the expression of clathrin and adaptor protein subunits are upregulated in maturation stage rodent enamel organ cells. AP complex 2 (AP-2) is the most upregulated of the four distinct adaptor protein complexes. Immunolocalization confirms the presence of AP-2 and clathrin in ameloblasts, with strongest reactivity at the apical pole. These data suggest that the resorptive functions of enamel cells involve AP-2 mediated, clathrin-dependent endocytosis, thus implying the likelihood of specific membrane-bound receptor(s) of enamel matrix protein debris. The mRNA expression of other endocytosis-related gene products is also upregulated during maturation including: lysosomal-associated membrane protein 1 (Lamp1); cluster of differentiation 63 and 68 (Cd63 and Cd68); ATPase, H(+) transporting, lysosomal V0 subunit D2 (Atp6v0d2); ATPase, H(+) transporting, lysosomal V1 subunit B2 (Atp6v1b2); chloride channel, voltage-sensitive 7 (Clcn7); and cathepsin K (Ctsk). Immunohistologic data confirms the expression of a number of these proteins in maturation stage ameloblasts. The enamel of Cd63-null mice was also examined. Despite increased mRNA and protein expression in the enamel organ during maturation, the enamel of Cd63-null mice appeared normal. This may suggest inherent functional redundancies between Cd63 and related gene products, such as Lamp1 and Cd68. Ameloblast-like LS8 cells treated with the enamel matrix protein complex Emdogain showed upregulation of AP-2 and clathrin subunits, further supporting the existence of a membrane-bound receptor-regulated pathway for the endocytosis of enamel matrix proteins. These data together define an endocytotic pathway likely used by ameloblasts to remove the enamel matrix during enamel maturation.


Assuntos
Complexo 2 de Proteínas Adaptadoras/fisiologia , Amelogênese , Endocitose/fisiologia , Animais , Western Blotting , Células Cultivadas , Lisossomos/metabolismo , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase , Ratos , Ratos Wistar , Tetraspanina 30/genética , Transcrição Gênica
10.
J Cell Physiol ; 227(4): 1776-85, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21732355

RESUMO

Transcellular bicarbonate transport is suspected to be an important pathway used by ameloblasts to regulate extracellular pH and support crystal growth during enamel maturation. Proteins that play a role in amelogenesis include members of the ABC transporters (SLC gene family and CFTR). A number of carbonic anhydrases (CAs) have also been identified. The defined functions of these genes are likely interlinked during enamel mineralization. The purpose of this study is to quantify relative mRNA levels of individual SLC, Cftr, and CAs in enamel cells obtained from secretory and maturation stages on rat incisors. We also present novel data on the enamel phenotypes for two animal models, a mutant porcine (CFTR-ΔF508) and the NBCe1-null mouse. Our data show that two SLCs (AE2 and NBCe1), Cftr, and Car2, Car3, Car6, and Car12 are all significantly up-regulated at the onset of the maturation stage of amelogenesis when compared to the secretory stage. The remaining SLCs and CA gene transcripts showed negligible expression or no significant change in expression from secretory to maturation stages. The enamel of CFTR-ΔF508 adult pigs was hypomineralized and showed abnormal crystal growth. NBCe1-null mice enamel was structurally defective and had a marked decrease in mineral content relative to wild-type. These data demonstrate the importance of many non-matrix proteins to amelogenesis and that the expression levels of multiple genes regulating extracellular pH are modulated during enamel maturation in response to an increased need for pH buffering during hydroxyapatite crystal growth.


Assuntos
Esmalte Dentário/crescimento & desenvolvimento , Esmalte Dentário/metabolismo , Amelogênese/genética , Amelogênese/fisiologia , Animais , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Antiporters/genética , Antiporters/metabolismo , Sequência de Bases , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Primers do DNA/genética , Esmalte Dentário/anormalidades , Concentração de Íons de Hidrogênio , Transporte de Íons , Masculino , Camundongos , Camundongos Knockout , Microscopia Eletrônica de Varredura , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Proteínas SLC4A , Simportadores de Sódio-Bicarbonato/deficiência , Simportadores de Sódio-Bicarbonato/genética , Simportadores de Sódio-Bicarbonato/metabolismo , Trocador de Sódio e Cálcio/genética , Sus scrofa
11.
J Androl ; 32(6): 565-75, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21441426

RESUMO

Water content within the male reproductive tract is stringently regulated in order to promote sperm differentiation and maturation. Aquaporins (AQP) are a family of integral membrane proteins allowing the transcellular transport of water, gases, urea, glycerol, and ions. Past studies from our lab have revealed the following. In the testis, Sertoli cells express AQP 8, whereas germ cells express AQP 7. In the efferent ducts (ED), AQP 1, 9, and 10 localize to microvilli of nonciliated cells, in addition to a basolateral staining for AQP 1, whereas AQP 1 and 10 localize to ciliated cells. AQP 7 and 11 are expressed in the ED epithelium of young but not adult rats, suggesting suppression of translation as rats age. In the adult epididymis, AQP 1 appears in endothelial cells of vascular channels and myoid cells, whereas AQP 3 delineates basal cells. In principal cells, AQP 9 and 11 appear on microvilli, whereas AQP 7 localizes to lateral then to basal plasma membranes in a region-specific manner; AQP 7 also associates with myoid cells. AQP 5 is expressed in corpus and cauda regions. Additionally, several AQPs are expressed by some but not all basal (AQP 7, 11), clear (AQP 7, 9), and halo (AQP 7, 11) cells. Regulation studies reveal a role for estrogen, androgens, and lumicrine factors. These findings indicate unique associations of AQPs with specific membrane domains in a cell type- and region-specific manner within the EDs and epididymis, as well as complex regulation patterns of expression.


Assuntos
Aquaporinas/metabolismo , Ductos Ejaculatórios/metabolismo , Epididimo/metabolismo , Testículo/metabolismo , Androgênios/metabolismo , Animais , Ductos Ejaculatórios/citologia , Epididimo/citologia , Estrogênios/metabolismo , Humanos , Masculino , Camundongos , Ratos , Testículo/citologia , Água/metabolismo
12.
Cell ; 144(5): 796-809, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21333348

RESUMO

Interactions between bone and the reproductive system have until now been thought to be limited to the regulation of bone remodeling by the gonads. We now show that, in males, bone acts as a regulator of fertility. Using coculture assays, we demonstrate that osteoblasts are able to induce testosterone production by the testes, though they fail to influence estrogen production by the ovaries. Analyses of cell-specific loss- and gain-of-function models reveal that the osteoblast-derived hormone osteocalcin performs this endocrine function. By binding to a G protein-coupled receptor expressed in the Leydig cells of the testes, osteocalcin regulates in a CREB-dependent manner the expression of enzymes that is required for testosterone synthesis, promoting germ cell survival. This study expands the physiological repertoire of osteocalcin and provides the first evidence that the skeleton is an endocrine regulator of reproduction.


Assuntos
Osso e Ossos/fisiologia , Fertilidade , Osteocalcina/fisiologia , Animais , Células Cultivadas , Humanos , Células Intersticiais do Testículo/fisiologia , Masculino , Camundongos , Osteoblastos/fisiologia , Testículo/fisiologia
13.
J Androl ; 32(4): 444-63, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21051588

RESUMO

Cystatin-related epididymal spermatogenic protein (CRES) or cystatin 8 (Cst8 gene) is a member of the cystatin superfamily of cysteine protease inhibitors. It differs from typical cystatins because it lacks consensus sites for cysteine protease inhibition and exhibits reproductive-specific expression. In the present study, we examined CRES expression within the testes, efferent ducts, and epididymides of normal mice by light microscope immunolocalization. Alterations to these tissues in male mice lacking the Cst8 gene (Cst8(-/-2)) were also characterized by histomorphometry and electron microscopy. In the normal testis, CRES was localized exclusively in mid and late elongating spermatids. In the efferent ducts, CRES was localized to the apical region of the epithelial cells suggestive of localization in the endosomes. In the initial segment of the epididymis, principal cells showed supranuclear and luminal reactions. In the cauda region, CRES was present exclusively as aggregates in the lumen and was detected in clear cells. Compared with wild-type mice (Cst8(+/+)), older (10-12 months) Cst8(-/-) mice had modest but statistically significant reductions in tubular, epithelial, and/or luminal profile areas in the testis and epididymis. By electron microscopy, some Cst8(-/-) tubules in the testis were normal in appearance, but others showed a vacuolated seminiferous epithelium, degenerating germ cells, and alterations to ectoplasmic specializations. In the epididymal lumen, abnormally shaped sperm heads and tails were noted along with immature germ cells. In addition, principal cells contained numerous large irregularly shaped lysosomes suggestive of disrupted lysosomal functions. In both the testis and epididymis, however, these abnormalities were not apparent in younger mice (4 months), only in the older (10-12 months) Cst8(-/-) mice. These findings suggest that the altered testicular and epididymal histology reflects a cumulative effect of the loss of CRES and support a role for CRES in maintaining the normal integrity and function of the testis and epididymis.


Assuntos
Cistatinas/fisiologia , Epididimo/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Cistatinas/genética , Epididimo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia , Microscopia Eletrônica , Testículo/metabolismo
14.
Eur J Oral Sci ; 119 Suppl 1: 199-205, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22243247

RESUMO

Mutations of the matrix metalloproteinase 20 (MMP20, enamelysin) gene cause autosomal-recessive amelogenesis imperfecta, and Mmp20 ablated mice also have malformed dental enamel. Here we showed that Mmp20 null mouse secretory-stage ameloblasts maintain a columnar shape and are present as a single layer of cells. However, the maturation-stage ameloblasts from null mouse cover extraneous nodules of ectopic calcified material formed at the enamel surface. Remarkably, nodule formation occurs in null mouse enamel when MMP20 is normally no longer expressed. The malformed enamel in Mmp20 null teeth was loosely attached to the dentin and the entire enamel layer tended to separate from the dentin, indicative of a faulty dentino-enamel junction (DEJ). The enamel rod pattern was also altered in Mmp20 null mice. Each enamel rod is formed by a single ameloblast and is a mineralized record of the migration path of the ameloblast that formed it. The enamel rods in Mmp20 null mice were grossly malformed or absent, indicating that the ameloblasts do not migrate properly when backing away from the DEJ. Thus, MMP20 is required for ameloblast cell movement necessary to form the decussating enamel rod patterns, for the prevention of ectopic mineral formation, and to maintain a functional DEJ.


Assuntos
Ameloblastos/enzimologia , Amelogênese/genética , Esmalte Dentário/anormalidades , Esmalte Dentário/ultraestrutura , Dentina/anatomia & histologia , Metaloproteinase 20 da Matriz/genética , Metaloproteinase 20 da Matriz/fisiologia , Ameloblastos/citologia , Ameloblastos/fisiologia , Animais , Calcinose/genética , Movimento Celular , Esmalte Dentário/enzimologia , Órgão do Esmalte/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Calcificação de Dente/genética
15.
Eur J Oral Sci ; 119 Suppl 1: 329-37, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22243264

RESUMO

Enamelin is a secreted glycoprotein that is critical for dental enamel formation. Ameloblasts in enamelin (Enam) null mice develop atypical features that include the absence of a Tomes' process, expanded endoplasmic reticulum, apparent loss of polarity, and pooling of extracellular matrix in all directions, including between ameloblasts and the stratum intermedium. We hypothesized that ameloblast pathological changes may be associated with increased cell apoptosis. Our objective was to assess apoptotic activity in maxillary first molars of wild-type, Enam(+/-), and Enam(-/-) mice at postnatal days 5, 7, 9, 14, and 17. Mouse maxillae were characterized by light microscopy after terminal deoxynucleotidyl transferase (TdT)-mediated biotin-dUTP nick-end labelling (TUNEL) or 5-bromo-2'-deoxyuridine (BrdU) staining. Following the initial deposition of dentin matrix, ameloblasts became highly dysplastic and no enamel crystal ribbons were deposited. Ameloblast apoptosis was observed in the Enam null mice starting in the secretory stage and with no apparent alteration in cell proliferation. We conclude that in the absence of enamelin and subsequent shutdown of enamel formation, ameloblasts undergo pathological changes early in the secretory stage that are evident as radically altered cell morphology, detachment from the tooth surface, apoptosis, and formation of ectopic calcifications both outside and inside the dystrophic enamel organ.


Assuntos
Ameloblastos/patologia , Amelogênese Imperfeita/genética , Amelogênese Imperfeita/patologia , Proteínas do Esmalte Dentário/genética , Animais , Apoptose , Bromodesoxiuridina/metabolismo , Calcinose , Proliferação de Células , Cristalização , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Knockout , Dente Molar/patologia , Calcificação de Dente/genética , beta-Galactosidase/genética
17.
Can J Anaesth ; 55(6): 358-63, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18566199

RESUMO

PURPOSE: Convective warming is routinely employed to maintain perioperative normothermia. However, due to differences in nozzle temperature and air flow of the power units, there are clinically relevant differences in heat transfer among convective warming systems. The purpose of this study was to evaluate the use of a quieter, convective warming system (WarmAir, sound pressure level 49 dba, air flow 35 cfm). The WarmAir system was compared to the standard, higher air flow system (Bair Hugger Model 750, sound pressure level 55 dba, air flow 48 cfm) with regards to temperature outcome. METHODS: Patients undergoing general anesthesia for major abdominal and orthopedic surgery were randomized into one of two groups: WarmAir or Bair Hugger. Both groups received an upper body, convective blanket using coverage appropriate for the given surgical procedure. Convective warming, at the high setting, was started after prepping and draping, and distal esophageal or nasopharyngeal temperature was measured intraoperatively. Sublingual temperature was measured preoperatively and on admission to the postanesthesia care unit. RESULTS: The WarmAir (n = 89) and Bair Hugger (n = 95) groups were similar with respect to age, gender, body mass index, ASA status, fluid balance, and duration of surgery. There was no difference in temperature outcomes between groups. In the WarmAir group, preoperative, lowest intraoperative, end of surgery, and postanesthesia care unit admission temperatures were (means +/- SD); 36.3 +/- 0.5, 35.4 +/- 1.1, 36.4 +/- 0.7, and 36.4 +/- 0.6 degrees C, respectively. Corresponding temperatures in the Bair Hugger group were; 36.3 +/- 0.6, 35.6 +/- 1.0, 36.5 +/- 0.6, and 36.4 +/- 0.5 degrees C, respectively. CONCLUSION: Despite differences in heating characteristics, both convective warming systems were effective in maintaining perioperative normothermia in patients undergoing major abdominal and orthopedic surgery. Therefore, choice of warming system is dependent on other factors such as ergonomics and cost.


Assuntos
Temperatura Corporal/fisiologia , Hipotermia/prevenção & controle , Complicações Intraoperatórias/prevenção & controle , Abdome/cirurgia , Adulto , Convecção , Feminino , Temperatura Alta , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos
18.
J Cell Biochem ; 103(3): 941-56, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17647262

RESUMO

We previously reported expression of a protein by enamel organ (EO) cells in rat incisors, originally isolated from the amyloid of Pindborg odontogenic tumors called Apin. The aim of the present study was to further characterize the Apin gene and its protein in various species, assess tissue specificity, and clarify its localization within the EO. Northern blotting and RT-PCR revealed that expression of Apin was highest in the EO and gingiva, moderate in nasal and salivary glands, and lowest in the epididymis. The protein sequences deduced from the cloned cDNA for rat, mouse, pig, and human were aligned together with those obtained from four other mammal genomes. Apin is highly conserved in mammals but is absent in fish, birds, and amphibians. Comparative SDS-PAGE analyses of the protein obtained from bacteria, transfected cells, and extracted from EOs all indicated that Apin is post-translationally modified, a finding consistent with the presence of predicted sites for phosphorylation and O-linked glycosylation. In rodent incisors, Apin was detected only in the ameloblast layer of the EO, starting at post-secretory transition and extending throughout the maturation stage. Intense labeling was visible over the Golgi region as well as on the apices of ameloblasts abutting the enamel matrix. Apin was also immunodetected in epithelial cells of the gingiva which bind it to the tooth surface (junctional epithelium). The presence of Apin at cell-tooth interfaces suggests involvement in adhesive mechanisms active at these sites, but its presence among other epithelial tissues indicates Apin likely possesses broader physiological roles.


Assuntos
Proteínas do Esmalte Dentário/metabolismo , Inserção Epitelial/metabolismo , Epitélio/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Ameloblastos/citologia , Ameloblastos/metabolismo , Sequência de Aminoácidos , Amiloide/química , Amiloide/genética , Amiloide/metabolismo , Animais , Linhagem Celular , Clonagem Molecular , Sequência Conservada , Proteínas do Esmalte Dentário/genética , Órgão do Esmalte/metabolismo , Inserção Epitelial/citologia , Proteínas da Matriz Extracelular/química , Proteínas da Matriz Extracelular/genética , Gengiva/citologia , Gengiva/metabolismo , Glicosilação , Células HeLa , Humanos , Incisivo/química , Incisivo/metabolismo , Camundongos , Tumores Odontogênicos/química , Tumores Odontogênicos/genética , Tumores Odontogênicos/metabolismo , Fosforilação , Biossíntese de Proteínas , Ratos , Alinhamento de Sequência , Suínos , Transcrição Gênica
20.
J Androl ; 28(5): 784-97, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17522420

RESUMO

Past studies have shown that the epithelial lining of the epididymis in adult mice deficient in protective protein cathepsin A (PPCA -/-) becomes swollen and vacuolated as a result of an accumulation of pale lysosomes, some very large, in addition to the presence of an abundance of macrophages infiltrating the intertubular spaces. The purpose of this study was to assess the integrity of the epididymal epithelial-blood barrier in these altered mice by characterizing the distribution of claudins (Cldns) and the leakiness of tight junctions to lanthanum nitrate. A second goal was to characterize sperm motility behavior in PPCA -/- mice using computer-assisted sperm analyses (CASA). The results indicated that lanthanum nitrate penetrated apical junctional complexes between adjacent epithelial cells and entered the epididymal lumen in PPCA -/- mice but not in control PPCA +/+ mice. Immunostaining for Cldns 1, 3, 8, and 10 revealed unique patterns of expression based on cell type and region specificity in PPCA +/+ mice, which were much different in PPCA -/- mice. PPCA -/- mice showed reduced intensities of immunoreactions, complete absence of immunoreactions, and appearance of atypical cytoplasmic immunoreactions. CASA indicated that sperm counts in the PPCA -/- mice were 70% reduced, and among other problems, there was a fourfold higher percentage of static sperm in PPCA -/- mice compared with controls. These results suggest that PPCA deficiency causes structural changes to the blood-epididymal barrier as evidenced by lanthanum nitrate and Cldns expression that affects the luminal environment of the epididymis, resulting in altered sperm motility.


Assuntos
Catepsina A/deficiência , Epididimo/fisiologia , Células Epiteliais/fisiologia , Proteínas de Membrana/metabolismo , Motilidade dos Espermatozoides/fisiologia , Junções Íntimas/fisiologia , Animais , Epididimo/irrigação sanguínea , Epididimo/ultraestrutura , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Imuno-Histoquímica , Lantânio , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Junções Íntimas/metabolismo
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