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1.
J Clin Med ; 11(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35743377

RESUMO

Thiazide diuretics have long been widely used as antihypertensive agents. In addition to reducing blood pressure, thiazides also control calcium homeostasis and increase bone density. We hypothesized that the use of thiazides in patients with hypertension would reduce overall fracture risk. We used the Taiwan National Health Insurance Research Database to find patients with a hypertension diagnosis who accepted antihypertensive treatment from 2000 to 2017. The patients were further classified into thiazide users and nonthiazide users. Multivariable Cox regression analysis and Kaplan-Meier survival analysis were performed to estimate the adjusted hazard ratios (aHRs) and cumulative probability of fractures. After 1:1 propensity score matching by sex, age, urbanization level of place of residence, income, comorbidities, and medications, there were 18,483 paired thiazide users and non-users, respectively. The incidence densities of fractures (per 1000 person-months) were 1.82 (95% CI: 1.76-1.89) and 1.99 (95% CI: 1.92-2.06) in the thiazide and nonthiazide groups, respectively. The results indicated a lower hazard ratio for fractures in thiazide users (aHR = 0.93, 95% CI: 0.88-0.98). Kaplan-Meier survival analysis revealed a significantly lower cumulative incidence of fractures in the thiazide group (log-rank test; p = 0.0012). In conclusion, our results reveal that thiazide use can reduce fracture risk. When antihypertensive agents are being considered, thiazide may be a better choice if the patient is at heightened risk of fracture.

2.
BMC Oral Health ; 21(1): 543, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34674692

RESUMO

BACKGROUND: Many types of titanium plates were used to treat subcondylar fracture clinically. However, the efficacy of fixation in different implant positions and lengths of the bone plate has not been thoroughly investigated. Therefore, the primary purpose of this study was to use finite element analysis (FEA) to analyze the biomechanical effects of subcondylar fracture fixation with miniplates at different positions and lengths so that clinicians were able to find a better strategy of fixation to improve the efficacy and outcome of treatment. METHODS: The CAD software was used to combine the mandible, miniplate, and screw to create seven different FEA computer models. These models with subcondylar fracture were fixed with miniplates at different positions and of different lengths. The right unilateral molar clench occlusal mode was applied. The observational indicators were the reaction force at the temporomandibular joint, von Mises stress of the mandibular bone, miniplate and screw, and the sliding distance on the oblique surface of the fracture site at the mandibular condyle. RESULTS: The results showed the efficacy of fixation was better when two miniplates were used comparing to only one miniplates. Moreover, using longer miniplates for fixation had better results than the short one. Furthermore, fixing miniplates at the posterior portion of subcondylar region would have a better fixation efficacy and less sliding distance (5.46-5.76 µm) than fixing at the anterolateral surface of subcondylar region (6.10-7.00 µm). CONCLUSION: Miniplate fixation, which was placed closer to the posterior margin, could effectively reduce the amount of sliding distance in the fracture site, thereby achieving greater stability. Furthermore, fixation efficiency was improved when an additional miniplate was placed at the anterior margin. Our study suggested that the placement of miniplates at the posterior surface and the additional plate could effectively improve stability.


Assuntos
Fraturas Mandibulares , Placas Ósseas , Fixação de Fratura , Fixação Interna de Fraturas , Humanos , Côndilo Mandibular/cirurgia , Fraturas Mandibulares/cirurgia
3.
BMC Cancer ; 20(1): 310, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293339

RESUMO

BACKGROUND: Cancer development is mediated by oxidative stress and inflammation, which may correlate with metabolic disorders. The aim of this study was to evaluate antioxidant vitamins status and metabolic parameters in patients with oral cancer according to tumor-node-metastasis (TNM) stages. METHODS: A total of 194 patients with oral cancer were enrolled in this study. The patients were stratified for four groups according to cancer stages and that the statistics are comparisons across these groups. The levels of antioxidant vitamins (ubiquinone, ß-carotene, vitamin A and E), metabolic parameters, oxidative stress, antioxidant enzymes activity, and inflammatory markers were measured. RESULTS: More than half of the subjects had high blood pressure, central obesity, hyperglycemia, and hyperlipidemia regardless of TNM stage. With regard to antioxidant vitamins status, 46 and 94% of patients had ß-carotene and ubiquinone deficiency, respectively. Patients in T3 and T4 stages had significantly lower antioxidant enzyme (catalase, p = 0.03) activity and higher inflammatory markers levels (high sensitivity C-reactive protein and interleukin-6, p < 0.01) than patients in the other stages. In addition, the level of ß-carotene was negatively associated with waist circumference, and ubiquinone was positively associated with the level of high-density lipoprotein cholesterol (p < 0.05). Higher ß-carotene and ubiquinone levels were negatively associated with hypertriglyceridemia and the risk of metabolic syndrome (p < 0.05). CONCLUSIONS: A high proportion of patients with oral cancer had ubiquinone or ß-carotene deficiency and metabolic disorders. The level of ubiquinone or ß-carotene was negatively associated with the risk of central obesity, hypertriglyceridemia, and metabolic syndrome. Since patients with oral cancer suffer from high oxidative stress and inflammation (particularly in the T3 and T4 stages), supplementation with antioxidant vitamins such as ubiquinone or ß-carotene could be preferentially applied.


Assuntos
Doenças Metabólicas/epidemiologia , Neoplasias Bucais/patologia , Ubiquinona/deficiência , beta Caroteno/deficiência , Adulto , Idoso , Proteína C-Reativa/metabolismo , Estudos Transversais , Feminino , Humanos , Interleucina-6/sangue , Masculino , Doenças Metabólicas/sangue , Doenças Metabólicas/classificação , Pessoa de Meia-Idade , Neoplasias Bucais/sangue , Estadiamento de Neoplasias , Estresse Oxidativo , Vitamina A/sangue , Vitamina E/sangue
4.
Appl Bionics Biomech ; 2019: 4989013, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281415

RESUMO

The bilateral sagittal split osteotomy (BSSO) technique is commonly used to correct mandibular deficiency. If the patient is exposed to excessive external forces after the procedure, occlusal changes or nonunion may occur. However, previous studies only focused on single external forces on the mandible and did not conduct relevant research on the forces exerted by different occlusion conditions. The main purpose of this study was to use finite element analysis methods to determine the biomechanics of four common occlusion conditions after BSSO surgical treatment. This study constructed a finite element analysis computer model of a miniplate implanted in the lower jaw. The structure of the model consisted of the mandible, miniplate, and screws. In addition, external forces were applied to the superficial masseter, deep masseter, medial pterygoid, anterior temporalis, middle temporalis, and posterior temporalis muscles to simulate the incisal clench, intercuspal position (ICP), right unilateral molar clench (RMOL), and right group function occlusion conditions. Subsequently, this study observed the effects of these conditions on the miniplate, screws, and mandible, including the von Mises stress values. The results showed that all of the different occlusion conditions that this study evaluated placed high stress on the miniplate. In the ICP and RMOL occlusion conditions, the overall mandibular structure experienced very high stress. The screw on the proximal segment near the bone gap experienced high stress, as did the screw on the buccal side. According to the present analysis, although the data were not directly obtained from clinical practice, the finite element analysis could evaluate the trend of results under different external forces. The result of this study recommended that patients without intermaxillary fixation avoid the ICP and RMOL occlusion conditions. It can be used as a pilot study in the future for providing clinicians more information on the biomechanics of implantation.

5.
IEEE Trans Biomed Circuits Syst ; 13(4): 766-780, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31135368

RESUMO

The paper proposes an innovative deep convolutional neural network (DCNN) combined with texture map for detecting cancerous regions and marking the ROI in a single model automatically. The proposed DCNN model contains two collaborative branches, namely an upper branch to perform oral cancer detection, and a lower branch to perform semantic segmentation and ROI marking. With the upper branch the network model extracts the cancerous regions, and the lower branch makes the cancerous regions more precision. To make the features in the cancerous more regular, the network model extracts the texture images from the input image. A sliding window is then applied to compute the standard deviation values of the texture image. Finally, the standard deviation values are used to construct a texture map, which is partitioned into multiple patches and used as the input data to the deep convolutional network model. The method proposed by this paper is called texture-map-based branch-collaborative network. In the experimental result, the average sensitivity and specificity of detection are up to 0.9687 and 0.7129, respectively based on wavelet transform. And the average sensitivity and specificity of detection are up to 0.9314 and 0.9475, respectively based on Gabor filter.


Assuntos
Algoritmos , Detecção Precoce de Câncer , Neoplasias Bucais/diagnóstico , Redes Neurais de Computação , Humanos , Processamento de Imagem Assistida por Computador , Análise de Ondaletas
6.
Oxid Med Cell Longev ; 2018: 9303094, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29951168

RESUMO

Oral cancer is the fifth leading cause of cancer death in Taiwan, and the prevalence of metabolic syndrome (MS) has also increased globally. The purpose of this study was to investigate the correlations between the components of MS and oxidative stress and inflammation in patients with oral cancer based on their areca-nut-chewing habits. Two hundred patients diagnosed with oral cancer were recruited, and metabolic parameters, oxidative stress, antioxidant enzyme activities, and inflammatory markers were measured. 63% of the subjects have concomitant MS. Subjects who had an areca-nut-chewing habit had significantly higher levels of fasting glucose (p = 0.04), oxidative stress (p = 0.02), and inflammatory markers (p = 0.02) than those who never chewed. High-density lipoprotein-cholesterol level (p = 0.03) and superoxidase dismutase activity (p = 0.02) were significantly lower in individuals who had chewed or were currently chewers. Areca-nut-chewing habit was associated with the increased risks for MS and hypertriglyceridemia; the components of MS were positively correlated with oxidative stress and inflammation. In conclusion, patients with oral cancer who had an areca-nut-chewing habit exhibited higher levels of oxidative stress and inflammation, which might be related to an increased risk of MS.


Assuntos
Areca/efeitos adversos , Inflamação/complicações , Síndrome Metabólica/complicações , Neoplasias Bucais/etiologia , Estresse Oxidativo/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Fatores de Risco , Adulto Jovem
7.
J Chin Med Assoc ; 81(4): 370-375, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29289482

RESUMO

BACKGROUND: The prognostic predict biomarkers are important in oral squamous cell carcinoma (OSCC). We investigated the expression patterns and quantitation of hypoxia-inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF) in OSCC patients. Among OSCC patients with recurrence and metastasis, the expression percentages of HIF-1α and VEGF also were analyzed. METHODS: Thirty-eight patients (8 hyperkeratosis, 30 oral squamous cell carcinoma) were included in this study. In the follow-up period, 5 OSCC patients had metastasis and 12 OSCC patients had local recurrence. We used computer-assisted image processing to analyze immunohistochemistry (IHC). The quantitative analysis of IHC slides, including upper-layer epithelium (U) and lower-layer epithelium (L), was calculated. RESULTS: We found homogeneous expression of VEGF in the epithelium. However, two patterns of HIF-1α expression were observed: homogeneous and heterogeneous. The highest U + L layer percentage in HIF-1α and VEF expression had significant association in tumor metastasis and recurrence (p<0.001 in HIF-1α and p<0.001 in VEGF). U + L layer HIF-1α expression percentage was >156.4%, and the survival rate was poor (p < 0.001). CONCLUSION: HIF-1α expression was not only influenced by tumor hypoxia, it also reflected tumor cell characteristics. High concentrations of VEGF and HIF-1α may have value as prognostic markers of tumor metastasis and recurrence.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Neoplasias Bucais/química , Carcinoma de Células Escamosas de Cabeça e Pescoço/química , Fator A de Crescimento do Endotélio Vascular/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Metástase Neoplásica , Estadiamento de Neoplasias , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
8.
Head Neck ; 38(3): 339-46, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25331819

RESUMO

BACKGROUND: The purpose of this study was to clarify the clinical implications of cases with recent dental extractions to establish a new classification of gingival squamous cell carcinoma (SCC). METHODS: A total of 156 patients were enrolled in this study. The subjects were divided into 3 groups: type I (dentate; n = 46), type II (edentulous; n = 55), and type III (dental extraction; n = 55). Continuous clinical and treatment variables were analyzed by 1-way analysis of variance (ANOVA) or t test, and categorical variables were evaluated by chi-square tests. Assessment of 5-year survival rates were carried out by the Kaplan-Meier analysis, and the influence of related factors was evaluated by the log-rank test. RESULT: The 55 type III patients showed a high probability of bony invasion (80%) and a lower 5-year survival rate (48%) than the other 2 groups. CONCLUSION: Our proposed classification may help clinicians to identify patients with gingival SCC who present with more advanced disease status.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Neoplasias Gengivais/diagnóstico , Extração Dentária/estatística & dados numéricos , Carcinoma de Células Escamosas/mortalidade , Feminino , Neoplasias Gengivais/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
9.
BMC Geriatr ; 14: 63, 2014 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-24886462

RESUMO

BACKGROUND: Hong Kong has one of the highest life expectancy rankings in the world. The number of centenarians and near-centenarians has been increasing locally and internationally. The relative growth of this population is a topic of immense importance for population and health policy makers. Living long and living well are two overlapping but distinct research topics. We previously conducted a quantitative study on 153 near-centenarians and centenarians to explore a wide range of biopsychosocial correlates of health and "living long". This paper reports a follow-up qualitative study examining the potential correlates of "living well" among near-centenarians and centenarians in Hong Kong. METHODS: Six cognitively, physically, and psychologically sound community-dwelling elders were purposively recruited from a previous quantitative study. Semi-structured interviews were conducted. RESULTS: Four major themes related to living long and well emerged from the responses of the participants: (a) Positive relations with others, (b) Positive events and happiness, (c) Hope for the future, and (d) Positive life attitude. Specifically, we found that having good interpersonal relationships, possessing a collection of positive life events, and maintaining salutary attitudes towards life are considered as important to psychological well-being by long-lived adults in Hong Kong. Most participants perceived their working life as most important to their life history and retired at very old ages. CONCLUSIONS: These findings also shed light on the relationships between health, work, and old age.


Assuntos
Nível de Saúde , Satisfação no Emprego , Satisfação Pessoal , Pesquisa Qualitativa , Características de Residência , Fatores Etários , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Hong Kong , Humanos , Masculino
10.
J Dig Dis ; 11(2): 106-10, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20402837

RESUMO

OBJECTIVE: To study the association between upper gastrointestinal (GI) problems and inhalational ketamine abuse. METHODS: This is a retrospective study of 64 ketamine abusers treated from 2001 to 2008. Variables studied included clinical presentations, findings of upper GI endoscopy, abstinence from ketamine and relief of epigastric pain. RESULTS: The following patients with (i) a previous history of upper GI problem; (ii) a history of non-steroidal anti-inflammatory drug (NSAID), aspirin or other substance abuse; and (iii) a known history of Helicobacter pylori (H. pylori) infection were excluded. The study group thus consisted of 37 ketamine abusers, of whom 28 had upper GI symptoms. Overall 14 of these patients had an upper endoscopy performed. The endoscopic diagnoses were: 12 (85.7%) with gastritis, one (7.1%) with gastroduodenitis, and one (7.1%) normal finding. Test for H. pylori, infection was negative. Abstinence from ketamine was found to be associated significantly with relief of symptoms (P= 0.027). Logistic regression showed the odds ratio of symptomatic relief for abstinence versus continued use of ketamine is 12.5 (95% CI[1.20, 130.6], P= 0.035). In patients whom an upper GI endoscopy was performed, H. pylori negative gastritis was the commonest histopathological finding (78.6%). Despite the use of medications, symptoms are commonly not relieved and that is associated with the continued abuse of ketamine. CONCLUSION: Ketamine abusers frequently presented with upper GI symptoms, the commonest of which is epigastric pain (73% of abusers). Abstinence from ketamine abuse can lead to the relief of symptoms, which is an important message for ketamine abusers.


Assuntos
Analgésicos/efeitos adversos , Gastrite/induzido quimicamente , Ketamina/efeitos adversos , Dor/induzido quimicamente , Transtornos Relacionados ao Uso de Substâncias/complicações , Administração por Inalação , Adulto , Analgésicos/administração & dosagem , China , Estudos de Coortes , Feminino , Gastrite/epidemiologia , Humanos , Incidência , Ketamina/administração & dosagem , Modelos Logísticos , Masculino , Dor/epidemiologia , Estudos Retrospectivos
12.
Head Neck ; 28(11): 998-1007, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16906513

RESUMO

BACKGROUND: Our objective was to determine the survival rate of patients with oral cancer who were treated at a medical center in central Taiwan. Furthermore, we attempted to investigate whether nutritional factors influence the survival. METHODS: We carried out a retrospective review of 1010 chart records of patients with oral cancer. We used the Kaplan-Meier method for survival analysis and the Cox proportional hazard models to investigate the prognosticators. RESULTS: Kaplan-Meier survival analysis showed an overall 5-year survival rate of 63.24%. The Cox proportional hazard model revealed that those with a preoperative body mass index (BMI) of <22.8 kg/m(2) tended to have a higher probability of death (relative risk [RR] = 1.292, p = .022). In addition, those with a preoperative serum albumin level of <4.15 g/dL were generally associated with a poorer prognosis (RR = 1.313, p = .016). CONCLUSIONS: Apart from clinical features, nutritional factors also had a significant influence on the survival of patients with oral cancer. Therefore, good nutritional status is crucial for patients with oral cancer in improving their survival.


Assuntos
Índice de Massa Corporal , Neoplasias Bucais/metabolismo , Neoplasias Bucais/mortalidade , Estado Nutricional , Albumina Sérica , Adulto , Análise de Variância , Estudos Transversais , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos
13.
Oral Oncol ; 42(9): 893-906, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16730220

RESUMO

The aim of this study was to determine the survival rate of oral cancer patients treated in a medical center in central Taiwan and to investigate whether socio-demographic factors influence their survival. We retrospectively reviewed 1010 chart records of oral cancer patients. Survival was analyzed by the Kaplan-Meier method and Cox proportional hazard model was used for investigating the relationship between socio-demographic factors and survival. The overall 5-year survival rate was 63.24%. Multivariate analysis revealed that those without religious belief tended to have higher probability of death than those who had religious belief (relative risk (RR): 2.057, p<0.001). In addition, those who were single, widow/widower or divorced/separated had a poorer prognosis than those who were married (RR: 1.528, p=0.008). Apart from clinical features, socio-demographic factors also significantly influenced the survival of oral cancer patients. Therefore, care providers should take socio-demographic issues into consideration aside from ordinary clinical health care.


Assuntos
Carcinoma de Células Escamosas/mortalidade , Neoplasias Bucais/mortalidade , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/psicologia , Estudos Transversais , Feminino , Humanos , Masculino , Estado Civil , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Neoplasias Bucais/psicologia , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Religião , Estudos Retrospectivos , Medição de Risco , Viés de Seleção , Classe Social , Análise de Sobrevida
14.
Health Care Manage Rev ; 31(1): 26-33, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16493270

RESUMO

This study examined whether social capital can enhance an individual's ability in reducing emotional exhaustion and job tension when medical professionals encounter a crisis such as Severe Acute Respiratory Syndrome (SARS).


Assuntos
Relações Interpessoais , Corpo Clínico Hospitalar/psicologia , Síndrome Respiratória Aguda Grave , Estresse Psicológico/prevenção & controle , Confiança , Adaptação Psicológica , China , Hong Kong , Humanos , Inquéritos e Questionários
15.
J Virol ; 78(16): 8615-29, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15280471

RESUMO

Herpesvirus lytic DNA replication requires both the cis-acting element, the origin, and trans-acting factors such as virally encoded origin-binding protein and DNA replication enzymes. Recently, the origins of lytic DNA replication (ori-Lyt) in Kaposi's sarcoma-associated herpesvirus (KSHV) have been identified and a virally encoded bZip protein, K8, has been shown to specifically bind to the origin. To map cis-acting elements within KSHV ori-Lyt that are required for DNA replication function and to define the nature of K8 bZip protein binding to the origin, we constructed consecutive internal deletion mutations across the core domain of a KSHV ori-Lyt and tested them for DNA replication function in a transient replication assay. This mutagenesis study allowed the identification of four components within the ori-Lyt, and all were indispensable for ori-Lyt function. The first component contains eight CCAAT/enhancer binding protein (C/EBP) binding motifs that organize as four spaced C/EBP palindromes. Each palindrome contains two head-to-head CCAAT consensus motifs that are separated by a 13- or 12-bp space sequence. Substitution mutagenesis of these C/EBP motifs showed that these C/EBP palindromes are required for both K8 binding and ori-Lyt-dependent DNA replication. The second component is an 18-bp AT palindrome, which is essential for ori-Lyt function. The third component was determined to be a 32-bp previously unidentified sequence and is required for DNA replication. The last component consists of an open reading frame 50 (ORF50)/Rta responsive element (RRE) and a TATA box. We showed that the binding of an ORF50/Rta protein to the RRE was essential for ori-Lyt-dependent DNA replication. The presence of a functional RRE and a downstream TATA box suggested that this region serves as an ORF50/Rta-dependent promoter and a transcription event may be necessary for ori-Lyt-dependent DNA replication. Using a luciferase reporter system, we demonstrated that the region of the RRE and TATA box constitutes an ORF50/Rta-dependent promoter. Furthermore, a polyadenylated RNA of 1.4 kb was identified downstream of the promoter.


Assuntos
Replicação do DNA , Elementos Facilitadores Genéticos , Herpesvirus Humano 8/fisiologia , Origem de Replicação , Transcrição Gênica , Proteínas Virais , Sequência de Aminoácidos , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina Básica , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular , DNA Viral/biossíntese , DNA Viral/genética , Regulação Viral da Expressão Gênica , Herpesvirus Humano 8/genética , Humanos , Dados de Sequência Molecular , Mutação , Proteínas Repressoras , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo
16.
Nat Cell Biol ; 6(5): 458-64, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15122269

RESUMO

Although the role of the epididymis, a male accessory sex organ, in sperm maturation has been established for nearly four decades, the maturation process itself has not been linked to a specific molecule of epididymal origin. Here we show that Bin1b, a rat epididymis-specific beta-defensin with antimicrobial activity, can bind to the sperm head in different regions of the epididymis with varied binding patterns. In addition, Bin1b-expressing cells, either of epididymal origin or from a Bin1b-transfected cell line, can induce progressive sperm motility in immotile immature sperm. This induction of motility is mediated by the Bin1b-induced uptake of Ca(2+), a mechanism that has a less prominent role in maintaining motility in mature sperm. In vivo antisense experiments show that suppressed expression of Bin1b results in reduced binding of Bin1b to caput sperm and in considerable attenuation of sperm motility and progressive movement. Thus, beta-defensin is important for the acquisition of sperm motility and the initiation of sperm maturation.


Assuntos
Epididimo/metabolismo , Maturação do Esperma/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo , beta-Defensinas/metabolismo , Animais , Cálcio/metabolismo , Técnicas de Cocultura , Epididimo/citologia , Células Epiteliais/metabolismo , Masculino , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Espermatozoides/citologia , beta-Defensinas/genética
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