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1.
Philos Trans A Math Phys Eng Sci ; 378(2183): 20190324, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32981443

RESUMO

Atmospheric reactive nitrogen (Nr) has been a cause of serious environmental pollution in China. Historically, China used too little Nr in its agriculture to feed its population. However, with the rapid increase in N fertilizer use for food production and fossil fuel consumption for energy supply over the last four decades, increasing gaseous Nr species (e.g. NH3 and NOx) have been emitted to the atmosphere and then deposited as wet and dry deposition, with adverse impacts on air, water and soil quality as well as plant biodiversity and human health. This paper reviews the issues associated with this in a holistic way. The emissions, deposition, impacts, actions and regulations for the mitigation of atmospheric Nr are discussed systematically. Both NH3 and NOx make major contributions to environmental pollution but especially to the formation of secondary fine particulate matter (PM2.5), which impacts human health and light scattering (haze). In addition, atmospheric deposition of NH3 and NOx causes adverse impacts on terrestrial and aquatic ecosystems due to acidification and eutrophication. Regulations and practices introduced by China that meet the urgent need to reduce Nr emissions are explained and resulting effects on emissions are discussed. Recommendations for improving future N management for achieving 'win-win' outcomes for Chinese agricultural production and food supply, and human and environmental health, are described. This article is part of a discussion meeting issue 'Air quality, past present and future'.


Assuntos
Poluição do Ar/efeitos adversos , Poluição Ambiental/efeitos adversos , Nitrogênio/efeitos adversos , Chuva Ácida/efeitos adversos , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , Biodiversidade , China , Ecossistema , Meio Ambiente , Poluição Ambiental/análise , Poluição Ambiental/prevenção & controle , Eutrofização , Política de Saúde , Humanos , Ozônio/efeitos adversos , Plantas/efeitos dos fármacos , Espécies Reativas de Nitrogênio/efeitos adversos , Solo/química
2.
Nanotechnology ; 30(30): 305303, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-30965292

RESUMO

We designed and fabricated a new type of superconducting quantum interference device (SQUID) susceptometers for magnetic imaging of quantum materials. The 2-junction SQUID sensors employ 3D Nb nano-bridges fabricated using electron-beam lithography. The two counter-wound balanced pickup loops of the SQUID enable gradiometric measurement and they are surrounded by a one-turn field coil for susceptibility measurements. The smallest pickup loop of the SQUIDs were 1 µm in diameter and the flux noise was around 1 µÐ¤0/√Hz at 100 Hz. We demonstrate scanning magnetometry, susceptometry and current magnetometry on some test samples using these nano-SQUIDs.

3.
Fa Yi Xue Za Zhi ; 35(5): 567-571, 2019 Oct.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-31833290

RESUMO

ABSTRACT: Objective To study the effect of overwork stress response on the expression of connexin 43(Cx43) and connexin 45(Cx45) in cardiomyocytes and on cardiac function. Methods The experimental animals were divided into control group, overworked 1-month group and overworked 2-month group. A overworked rat model was established by forcing swimming of overworked group. The expressions of Cx43 and Cx45 in myocardial tissues of experimental animals were detected by Western blotting, while the corresponding myocardial tissues were stained with hematoxylin-eosin (HE) staining and Masson's staining, then histologically observed. Results Western blotting results showed that, compared with the control group, Cx43 expression in myocardial tissues of overworked rats decreased while Cx45 expression increased. HE staining and Masson's staining results showed that hypertrophy, rupture and interstitial fiber tissue hyperplasia were observed in myocardial fibers of overworked rats. Conclusion Overwork stress response may affect cardiac function as an independent factor and may even cause heart failure or arrhythmias and lead to death.


Assuntos
Arritmias Cardíacas/etiologia , Conexina 43/metabolismo , Conexinas/metabolismo , Insuficiência Cardíaca , Miócitos Cardíacos/metabolismo , Animais , Arritmias Cardíacas/metabolismo , Miocárdio , Ratos
4.
Beijing Da Xue Xue Bao Yi Xue Ban ; 49(6): 1038-1043, 2017 Dec 18.
Artigo em Zh | MEDLINE | ID: mdl-29263478

RESUMO

OBJECTIVE: To understand the cognition and behavior of drug safety in Beijing middle school students and provide advice for relevant education. METHODS: A cross-sectional survey using paper questionnaires was carried out on the student body of nine Beijing middle schools. Multi-stage proportionate stratified cluster sampling was adopted to enroll participants. In addition to demographic questions, the questionnaire included 17 questions assessing the cognition and behavior of safe drug use, prioritizing questions that aligned with the health education guideline for primary and secondary school students from Chinese Ministry of Education. Descriptive statistical methods were applied using the SAS 9.2 software. RESULTS: Of the 4 220 students investigated, 2 097(49.7%) were males and 2 123(50.3%) were females. The average age was (14.3±1.7) years. 2 030(48.1%) students were from downtown areas, 1 511(35.8%) were from urban-rural linking areas and 679(16.1%) were from rural areas. Half (51.5%) of the respondents were junior high school students, and the others were from senior high schools (34.2%) and vocational high schools (14.3%). Most of the students (89.6%) lived off campus. The awareness rate of drug safety knowledge was 74.4%, the median score of drug safety behavior was 4 points (full score was 5 points) and there was a statistically positive correlation between the two (Spearman's correlation coefficient was 0.156, P<0.001). Both the awareness rates and the drug safety behavior scores were statistically different among the students in different regions, different school types and different residence types (P<0.001). Multiple factors analysis demonstrated the correlation between the cognition degrees of both drug safety knowledge, behavior and the above factors. Of all the students, 80.4% agreed that any drug could have adverse drug reactions; 40.5% were aware that antibiotics couldn't kill viruses; as many as 49.6% mistook aspirin as antibiotic; 97.4% would read drug instructions before taking them; Only 42.4% put expired drugs into special recycling bins; 49.8% would deviate from the suggested dosage and frequency of their medication when they were sick with common diseases. CONCLUSION: Overall, the cognition of drug safety in Beijing middle school students is good, but problems still exist in medication adherence, the management of expired drugs and the antibiotics cognition, which need to be fixed through specific, pointed way of education. And more efforts should be made to improve the cognition in rural regions, vocational high schools and on campus students.


Assuntos
Cognição , Instituições Acadêmicas , Estudantes , Adolescente , Pequim , Criança , Estudos Transversais , Feminino , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , População Rural , Inquéritos e Questionários
5.
Genet Mol Res ; 15(1)2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26909953

RESUMO

Genetic variations in human interleukin-1 (IL-1) genes are known to be involved in inflammatory disorders. The rs17561 and rs1143634 polymorphisms of IL-1α and IL-1ß, respectively, have been increasingly recognized as important regulators in the development of periodontitis. However, the existence of a specific association remains controversial. Therefore, we performed a meta-analysis to explore the relationship between IL-1 polymorphism and periodontitis risk. Based on our inclusion criteria, six case-control studies were used, involving a total of 336 periodontitis cases and 366 healthy controls. Our meta-analysis results showed that the T allele of IL-1α rs17561 is positively associated with periodontitis susceptibility. In addition, carriers of this allele (TC + TT genotypes) demonstrated increased risk of this disease. The IL-1ß rs1143634 T allele was also positively connected to periodontitis, with TC + TT genotype carriers being significantly more at risk. These results demonstrate that the IL-1α rs17561 and IL-1ß rs1143634 polymorphisms are associated with periodontitis.


Assuntos
Predisposição Genética para Doença , Interleucina-1alfa/genética , Interleucina-1beta/genética , Periodontite/genética , Polimorfismo de Nucleotídeo Único , Alelos , Estudos de Casos e Controles , Frequência do Gene , Humanos , Interleucina-1alfa/imunologia , Interleucina-1beta/imunologia , Periodontite/imunologia , Periodontite/patologia , Risco
6.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 59(4): 336-343, 2024 Apr 09.
Artigo em Zh | MEDLINE | ID: mdl-38548590

RESUMO

Objective: To evaluate the clinical outcomes after implant restoration in the posterior region of severe periodontitis patients and to investigate the factors of natural tooth affecting the implant from the perspective of improving natural periodontal health, which may provide a reference for clinical practice. Methods: Fifty-three patients with severe periodontitis who visited the Department of Periodontology at the Affiliated Stomatological Hospital of China Medical University from June 2014 to June 2023 and completed posterior implant treatment with single crown were included, among which were 16 males and 37 females, aged (52.2±8.0) years old, with a total of 136 implants, 135 adjacent natural teeth in the edentulous area. We retrospectively compared the changes of probing depth (PD), bleeding on probing (BOP) and tooth mobility (TM) before and after implant placement. Besides, we explored the effects of the natural periodontal status on PD, BOP and marginal bone loss (MBL) of the implant at the last follow-up examination by univariate analysis and multivariate analysis. Results: Fifty-three patients were followed up for (44.5±14.1) months in average, with longest interval of (8.3±2.7) months. The PD of adjacent natural teeth in the edentulous area improved from 4.3 (3.6, 4.6) mm before implantation to 3.6 (3.2, 4.0) mm in the last review (P<0.01), while the proportion of BOP (+) improved from 69.6% (94/135) before implantation to 46.7% (63/135) in the last review (P<0.01). The proportion of teeth with mobility≥Ⅱ decreased from 15.6% (21/135) to 5.9% (8/135) (P<0.01). The percentage of natural teeth with PD≥4 mm in the same segment improved from 21.0% (13.3%, 26.0%) before implantation to 18.0% (12.0%, 25.0%) in the last review (P<0.05). The BOP (+)% improved from 29.0% (24.0%, 35.0%) before implantation to 23.0% (18.0%, 31.0%) in the last review (P<0.05), and the number of teeth with mobility≥Ⅱ decreased from 0.0 (0.0, 1.0) to 0.0 (0.0, 0.8) (P<0.05). The functional tooth unit score of full natural teeth increased from 8.0 (6.0, 10.0) points before implantation to 12.0 (12.0, 12.0) points in the last review (P<0.01). PD≥4 mm % increased from 11.0% (6.0%, 25.0%) before implantation to 13.0% (3.0%, 21.0%) in the last review (P<0.05) and there was no significant differences in BOP (+)% [(17.0±9.7) % vs (14.6±7.2) %, P>0.05]. The number of teeth with mobility≥Ⅱ decreased from 1.0 (0.0, 1.8) to 0.0 (0.0, 0.8) (P<0.05). Conclusions: Under the premise of regular supportive care, implant restorative treatment in the posterior region of severe periodontitis patients is helpful to improve the PD, BOP and TM of remaining natural teeth. Besides, the stages and grades of periodontitis at initial diagnosis can affect the PD and BOP of implants.


Assuntos
Implantes Dentários , Boca Edêntula , Periodontite , Dente , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Periodontite/complicações
7.
Zhonghua Nei Ke Za Zhi ; 57(6): 457-458, 2018 Jun 01.
Artigo em Zh | MEDLINE | ID: mdl-29925134
8.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 58(3): 298-304, 2023 Feb 28.
Artigo em Zh | MEDLINE | ID: mdl-36854434

RESUMO

Severe periodontitis is the main cause of tooth loss in adults, with varying degrees of horizontal and vertical alveolar bone loss. In view of the complex alveolar bone defect, a suitable surgery planning should be made on the basis of fully nuderstanding the characteristics of alveolar bone defect in severe periodontitis and the key points of bone augmentation technique, so as to choose an appropriate method for reconstruction of alveolar bone and complete the implantation and restoration to ensure the integrity of dentition, which are important for the long-term stability of periodontal health. Based on clinical experiences and literature review, we summarizes the characteristics of alveolar bone loss in patients with severe periodontitis and the timing of implant placement after bone augmentation surgery, in order to provide reference for implant treatment of severe periodontitis.

9.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 58(10): 1051-1061, 2023 Oct 09.
Artigo em Zh | MEDLINE | ID: mdl-37730417

RESUMO

Oral microbial community, as an important part of human microbial community, is closely related to oral and general health. Oral microbiological research has become the forefront of international microbiological research. Standardized and unified nomenclature for oral microorganisms in Chinese is of great significance to support the development of oral medicine research. Standardized translation of microbial names is the basis for writing canonical and authoritative professional textbooks and reference books, which helps students to accurately acquire the characteristics and classifications of oral microbes. Unified translation of oral microorganisms is also conducive to academic communication and cooperation, and plays an important role in oral health education and science popularization, which enables oral microbiology knowledge to be accurately disseminated to the public. Therefore, in order to standardize the words in scientific research, funding application, publications, academic exchanges and science popularization within the field of oral medicine, we have fully discussed and revised the Chinese names of oral microorganisms in 2017 edition and ones of newly discovered oral microbes, finally reaching a consensus to form the 2023 edition of Chinese names of oral microorganisms.

10.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 57(6): 648-653, 2022 Jun 09.
Artigo em Zh | MEDLINE | ID: mdl-35692011

RESUMO

The oral cavity is the second largest microbial habitat in the whole body. Due to the divergence of oxygen, metabolic substrates and rate-limiting enzymes, oral bacteria are classified into sugar-metabolizing and nitrogen-compound-metabolizing bacteria according to their metabolic characteristics. The metabolites include organic acids, carbon dioxide, amino acids, proteins, and ammonia. Oral bacterial metabolites are very important for oral bacteria growth and reproduction, and also play an important role in systemic diseases such as periodontitis, oral cancer, intestinal diseases, diabetes and atherosclerosis. Therefore, in-depth exploration of oral bacterial metabolism is of great significance to understand the impact of oral cavity on systemic health. This article reviews the metabolic characteristics of oral bacteria and their correlation with systemic diseases.


Assuntos
Microbiota , Periodontite , Bactérias , Humanos , Periodontite/microbiologia
11.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(8): 769-776, 2021 Aug 09.
Artigo em Zh | MEDLINE | ID: mdl-34404143

RESUMO

Objective: To evaluate the levels of alveolar bone defects by using cone-beam CT in periodontitis patients with history of orthodontic treatment and to find the special tooth positions, sites and periodontitis stages of alveolar bone defects, so as to provide reference for the formulation of clinical personalized diagnosis and treatment plans. Methods: Thirty patients who were diagnosed as Angle class Ⅱ malocclusion, treated by using labial fixed orthodontic appliances and also diagnosed as periodontitis (orthodontic group) were recuited from January 2009 to June 2019 at the School and Hospital of Stomatology, China Medical University in the present study. They were aged (27.0±5.4) years old (ranged 18-41 years old). Another 60 periodontitis patients without a history of orthodontic treatment matched according to age, gender and severity of periodontitis were selected as control group (non-orthodontic group). They were aged (26.7±5.2) years old (ranged 18-41 years old). Cone-beam CT images were used to measure the heights of the alveolar bone defects at each tooth position of the patients. The difference in the heights of the alveolar bone defects between the orthodontic group and the non-orthodontic group at the same position of the maxillary and mandibular alveolar bones were compared. The specificities of the defect heights in different positions of the maxillary and mandibular alveolar bones and different sites of the same tooth position were analyzed among orthodontic group. The specificities of the different tooth positions of the maxillary and mandibular alveolar bones of the different periodontitis stages among orthodontic group were compared. Results: The heights of the alveolar bone defects in the maxillary canine area and molar area, the mandibular incisor area, the canine area and the premolar area in the orthodontic group were higher than that in the non-orthodontic group, and the differences were statistically significant (P<0.05). In orthodontic group, the most severe teeth in the maxillary and mandibular alveolar bone defects were the canine areas [(3.75±1.00), (3.83±1.10) mm]. Secondly, the more severe tooth positions of the maxillary alveolar bone height defects were the molar area [(3.67±0.84) mm] and the incisor area [(3.39±0.83) mm] and the more severe tooth positions of the mandibular alveolar bone defects were the incisor area [(3.73±1.42) mm] and the molar area [(3.54±0.81) mm]. The height of the alveolar bone defect in the mandibular incisor area was greater than that in the maxillary (P<0.05). The bone defect in the maxillary molar area was severer than that of the mandibular area (P<0.05). The alveolar bone defects in the buccal and lingual sides were mostly larger than that of the mesial and distal sides both in maxillary and mandibular positions except for the maxillary incisor area(P<0.05). The most severe alveolar bone defect position changed with the periodontitis stage. The most severe tooth position of the maxillary in stage Ⅰ periodontitis was in the molar area [(3.26±0.63) mm], whereas the incisor area was the most severe tooth of the mandible [(3.14±1.04) mm]. In addition, among maxillary incisor area, canine area, premolar area, molar area, the most severe alveolar bone defect height was the canine area in stage Ⅱ, Ⅲ, Ⅳ mandibular (P<0.05). Conclusions: In periodontitis patients with a history of orthodontic treatment, the height of the alveolar bone defect was specific to the tooth positions and sites. With the periodontitis stage changing, the most severe defect position changed in both maxillary and mandibular alveolar bones. It is recommended to pay more attention to the alteration of alveolar bone in periodontitis patients with a history of orthodontic treatment and give timely targeted treatment plans.

12.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 54(2): 87-93, 2019 Feb 09.
Artigo em Zh | MEDLINE | ID: mdl-30695909

RESUMO

Objective: To analysis the effect of nonoperative periodontal treatment on morphological changes of the schneiderian membrane of maxillary sinus in the chronic periodontitis patients by using oro-maxillaofacial cone-beam CT (CBCT) in order to provide the foundation in the diagnosis and treatment of maxillary sinusitis caused by chronic periodontitis. Methods: Totally 30 chronic periodontitis patients with schneiderian membrane thickening [(40.0±5.6) years old (ranged 26-55 years old), 18 males and 12 females] were randomly recruited in Department of Periodontics, School of Stomatology, China Medical University from June 2014 to December 2016. All patients were scanned by CBCT. The probing depth (PD), clinical attachment loss (CAL), plaque index (PLI) and bleeding index (BI) of the maxillary first and second premolars and molars were recorded. All patients received systematic nonoperative periodontal treatment. After six months, patients were reviewed, periodontal indexes and CBCT scanning were recorded. The thickness of the schneiderian membrane of maxillary sinus were analyzed by the software of CBCT. The changes of clinical parameters, parameter dimensional values of membrane thickness before and after treatment were statistically compared by t test. Results: In 30 chronic periodontitis patients, there was no statistically significant difference in the dimension and length of the maxillary sinus mucosa between the right and the left (P>0.05). The dimension of the mucosal thickening was positively correlated with PD and CAL values, and the correlation was statistically significant (P<0.05). Totally 58 maxillary sinus showed mucosal thickening. There were 20 mild thickening cases, and the dimension of mucosal thickening 6 months after treatment [(1.1±0.6) mm] was significantly lower than that before treatment [(2.5±0.7) mm] (P<0.05). There were 30 moderate thickening cases and the dimension of mucosal thickening 6 months after treatment [(2.3±0.6) mm] was significantly lower than that before treatment [(5.8±0.5) mm] (P<0.01). There were 8 severe thickening cases and the dimension of mucosal thickening 6 months after treatment [(4.2±0.4) mm] was also significantly lower than that before treatment [(11.2±1.8) mm] (P<0.01). The periodontal indexes of patients with mild, moderate and severe mucosal thickening in maxillary sinus showed statistically significant difference after treatment compared with before treatment (P<0.05). Conclusions: Nonoperative periodontal treatment has a positive therapeutic significance for improving the schneiderian membrane thickening of maxillary sinus.


Assuntos
Periodontite Crônica , Seio Maxilar , Mucosa Nasal , Adulto , China , Periodontite Crônica/diagnóstico , Periodontite Crônica/patologia , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Seio Maxilar/patologia , Pessoa de Meia-Idade , Mucosa Nasal/diagnóstico por imagem , Mucosa Nasal/patologia
13.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 53(3): 150-156, 2018 Mar 09.
Artigo em Zh | MEDLINE | ID: mdl-29972970

RESUMO

Objective: To detect the inhibitory ability of histatin 5 on the auto-aggregation of Porphyromonas gingivalis (Pg), and the co-aggregation of Pg with Fusobacterium nucleatum (Fn); and to provide a theoretical basis for the role of oral innate immunity played in the inhibition of chronic periodontitis. Methods: Saliva and supragingival, subgingival plaque samples were collected from 49 chronic periodontitis patients in School of Stomatology, China Medical University and 27 periodontal healthy individuals. Enzyme linked immunosorbent assay was used to assess the amount of histatin 5 in saliva, absolute quantitative real-time PCR (qPCR) was applied to detect the DNA copies of Fn, Pg and total bacteria in supragingival and subgingival plaque samples. The effects of histatin 5 on auto- and co-aggregation were assessed by bacterial adhesion test and scanning electron microscopy. Hemagglutinin gene, arginine-gingipains gene in Pg and FomA gene in Fn were tested by relative qPCR. Independent samples t-test was used to calculate the significance between the experimental group and the control group. P-value<0.05 was considered statistically significant. Results: For chronic periodontitis patients, there was an inverse correlation between the concentration of histatin 5 and Fn and Pg in supragingival plaque samples (r=-0.379, r=-0.624). Similarly, an inverse correlation was also observed between the concentration of histatin 5 and subgingival Fn and Pg, respectively (r=-0.404, r=-0.314). As for periodontally healthy individuals, there was an inverse correlation between the concentration of histatin 5 and supragingival and subgingival Pg (r=-0.572, r=-0.533). Bacterial adhesion test and scanning electron microscopy certified that 25 mg/L histatin 5 inhibited the auto-aggregation of Pg-Pg and the co-aggregation of Pg-Fn. Results of qPCR showed that 25 mg/L histatin 5 up-regulated hemagglutinin gene by (14.52±3.25) fold and down-regulated FomA gene to (0.22±0.10) fold. Conclusions: Histatin 5 could inhibit the auto-aggregation of Pg-Pg and the co-aggregation of Pg-Fn by regulating hemagglutinin gene and FomA gene expression.


Assuntos
Periodontite Crônica/imunologia , Fusobacterium nucleatum/efeitos dos fármacos , Histatinas/farmacologia , Porphyromonas gingivalis/efeitos dos fármacos , Saliva/química , Aderência Bacteriana/efeitos dos fármacos , Proteínas da Membrana Bacteriana Externa/genética , China , Periodontite Crônica/microbiologia , DNA Bacteriano/análise , Placa Dentária/microbiologia , Feminino , Fusobacterium nucleatum/fisiologia , Expressão Gênica , Hemaglutininas/genética , Histatinas/análise , Humanos , Porphyromonas gingivalis/fisiologia , Reação em Cadeia da Polimerase em Tempo Real
14.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 52(2): 77-80, 2017 Feb 09.
Artigo em Zh | MEDLINE | ID: mdl-28253580

RESUMO

Radiotherapy and chemotherapy might change the healing process of periodontal disease by reducing there storability of the periodontal tissues, leading the increase of attachment lose and alveolar bone absorption. The primary periodontal lesions could be aggravated. Therefore, oral screening should be conducted before periodontal treatment, in order to eliminate dental focal infection, to stabilize the oral environment and to prevent and reduce complications after cancer treatment. The patient's general situation should be evaluated before the periodontal treatment too, so as to ensure the patient could tolerate the radiotherapy and chemotherapy in the short interval between diagnosis and treatment of cancer. The periodontal treatment should be more conservative than normal periodontal patients. The indication for tooth extraction in these patients should be less conservative.


Assuntos
Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Doenças Periodontais/terapia , Perda do Osso Alveolar/etiologia , Tratamento Conservador , Humanos , Doenças Periodontais/complicações , Periodonto/efeitos dos fármacos , Periodonto/efeitos da radiação , Extração Dentária
15.
J Med Chem ; 36(24): 3923-8, 1993 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-7902869

RESUMO

A series of N-(1-arylpropionyl)-4-aryl-1,2,3,6-tetrahydropyridines, prepared by simple Mannich condensations, have been found by radioligand binding assays to have moderate to high affinity (IC50 0.5-500 nM) for bovine cerebellar sigma receptor/binding sites and no measurable affinity (IC50 > 5000 nM) for bovine striatal D2 receptors. The most active of these compounds rival in potency the most active sigma ligands previously reported. Three of these sigma-active compounds were screened for pharmacological activity under the NIMH-NovaScreen program and showed moderate affinity only for D2 and 5-HT2 receptors among the 40 sites assayed. Since these N-(1-arylpropionyl)-4-aryltetrahydropyridines are structurally related to other potent sigma receptor ligands, in particular haloperidol and 4-phenylpiperidines, these data provide insights into the nature of the essential pharmacophore of the sigma receptor. The selective affinity of these materials for sigma receptors indicates they have potential as prototypes of novel psychotherapeutic medicinal agents, particularly as antipsychotic drugs which would be devoid of debilitating side effects associated with blockade of D2 receptors.


Assuntos
Antipsicóticos/síntese química , Di-Hidropiridinas/síntese química , Propiofenonas/síntese química , Piridinas/síntese química , Receptores sigma/metabolismo , Animais , Antipsicóticos/metabolismo , Sítios de Ligação , Ligação Competitiva , Bovinos , Cerebelo/metabolismo , Di-Hidropiridinas/metabolismo , Haloperidol/metabolismo , Ketanserina/farmacologia , Propiofenonas/metabolismo , Piridinas/metabolismo , Ensaio Radioligante , Receptores de Dopamina D2/metabolismo , Receptores de Serotonina/metabolismo , Espiperona/metabolismo , Espiperona/farmacologia
16.
Int J Gynaecol Obstet ; 56(1): 3-11, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9049688

RESUMO

OBJECTIVE: The nomogram of blood velocity flow resistance of the spiral arteries was built at 13-25 gestational weeks. Thereafter, by using the nomogram we tried to assess the results of the color Doppler examination of the uteroplacental circulation at the second trimester to predict pregnancy-induced hypertension (PIH) and small-for-gestational-age (SGA). METHODS: Two groups of patients were studied. Group 1, for the establishment of the nomogram, included 175 uncomplicated pregnancies with gestational ages ranging from 13-25 weeks. The Doppler flow waveforms of the spiral arteries were measured once for each pregnancy in the studies. Group 2 consisted of 305 singletons selected consecutively for prospective study to confirm the occurrence of PIH or SGA. They were scanned twice for the measurements of the spiral artery waveforms at 13-19 and 20-25 weeks, respectively to test which gestational weeks interval in the nomogram is most sensitive in predicting PIH and SGA. RESULTS: The 5th, 50th and 95th percentiles of the pulsatility index (PI) values of the nomogram at the second trimester were used as the cut-off points to predict pregnancies complicated with SGA or PIH at delivery. Using the receiver operator curve, the 50th percentiles of the PI values of the nomograms were chosen as predictives for the development of PIH and SGA. At 13-19 gestational weeks, the specificities in predicting PIH and SGA were 50.71% and 49.82%, respectively, and the sensitivities were 52.00% and 50.00%, respectively. The calculated Cohen's Kappa statistics were 0.008 and 0.001, respectively in predicting PIH and SGA. At 20-25 gestational weeks, the specificities in predicting PIH and SGA were 49.64% and 49.46%, respectively, and the sensitivities were 56.00% and 57.14%, respectively. The calculated Cohen's Kappa statistics were 0.017 and 0.022, respectively in predicting PIH and SGA. CONCLUSION: The measurements of uteroplacental blood flow velocity waveforms at the second trimester are not sensitive enough to be an early screening tool for PIH and SGA in the low risk, non-selected pregnancy population. The fact suggests that in most gravidas complicated with PIH and SGA, the physiological process of trophoblastic invasion in the spiral artery was not prevented before the 25th gestational week.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Hipertensão/diagnóstico por imagem , Recém-Nascido Pequeno para a Idade Gestacional/fisiologia , Placenta/irrigação sanguínea , Complicações Cardiovasculares na Gravidez/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Útero/irrigação sanguínea , Feminino , Idade Gestacional , Humanos , Hipertensão/fisiopatologia , Recém-Nascido , Gravidez , Complicações Cardiovasculares na Gravidez/fisiopatologia , Segundo Trimestre da Gravidez , Curva ROC , Valores de Referência , Fatores de Risco , Resistência Vascular/fisiologia
18.
Oncogene ; 29(43): 5785-95, 2010 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-20711237

RESUMO

LAPTM4B (lysosomal protein transmembrane 4 beta) is a newly identified cancer-associated gene. Both of its mRNA and the encoded LAPTM4B-35 protein are significantly upregulated with more than 70% frequency in a wide variety of cancers. The LAPTM4B-35 level in cancer is evidenced to be an independent prognostic factor and its upregulation promotes cell proliferation, migration and invasion, as well as tumorigenesis in nude mice. In contrary, knockdown of LAPTM4B-35 expression by RNA interference (RNAi) reverses all of the above malignant phenotypes. We herein reveal a new role of LAPTM4B-35 in promoting multidrug resistance of cancer cells. Upregulation of LAPTM4B-35 motivates multidrug resistance by enhancement of efflux from cancer cells of a variety of chemodrugs with variant structures and properties, including doxorubicin, paclitaxel and cisplatin through colocalization and interaction of LAPTM4B-35 with multidrug resistance (MDR) 1 (P-glycoprotein, P-gp), and also by activation of PI3K/AKT signaling pathway through interaction of PPRP motif contained in the N-terminus of LAPTM4B-35 with the p85α regulatory subunit of PI3K. The specific inhibitors of PI3K and knockdown of LAPTM4B-35 expression by RNAi eliminate the multidrug resistance effect motivated by upregulation of LAPTM4B-35. In conclusion, LAPTM4B-35 motivates multidrug resistance of cancer cells by promoting drug efflux through colocalization and interaction with P-gp, and anti-apoptosis by activating PI3K/AKT signaling. These findings provide a promising novel strategy for sensitizing chemical therapy of cancers and increasing the chemotherapeutic efficacy through knockdown LAPTM4B-35 expression by RNAi.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Membrana/genética , Proteína Oncogênica v-akt/metabolismo , Proteínas Oncogênicas/genética , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/metabolismo , Western Blotting , Separação Celular , Citometria de Fluxo , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Imunoprecipitação , Proteínas de Membrana/metabolismo , Microscopia Confocal , Proteínas Oncogênicas/metabolismo , Transfecção , Regulação para Cima
19.
Oral Microbiol Immunol ; 16(4): 235-42, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11442849

RESUMO

Streptococcus sanguis comprises a heterogeneous group of oral streptococci indigenous to the oral cavity of humans. A total of 289 isolates from an infant population (n=37) were tentatively identified as S. sanguis on the basis of the distinctive colony morphology as shown on MM10-sucrose non-selective medium. These isolates were divided into four biovars of S. sanguis as determined by an extended panel of biochemical attributes. Chromosomal DNA was extracted from each isolate, and an AP-PCR fingerprint profile was obtained to allow study of the diversity within and among the infants. In this study, all four biovars of S. sanguis were detected in the infants. A wide genotypic diversity of S. sanguis was observed among these isolates; on average, each infant harbored 2.7 unique amplitypes as shown by the AP-PCR fingerprints. To explore the phylogenic relationship among these S. sanguis isolates, 20 strains representing the four biovars were selected at random for sequencing of their 16S rDNA and 16S-23S rDNA intergenic spacer chromosomal loci. Two major sequence patterns were identified within the 16S rDNA sequences. A phylogenic analysis showed that members from each of the four biovars of S. sanguis bore close relationship with the type-strain ATCC 10556 sequence, and that all of the isolates representing the four biovars could be clustered into two main phylotypes. The biovars were distributed throughout the phylotypes, indicating no correlation between the genetic and phenotypic groupings.


Assuntos
Boca/microbiologia , Streptococcus sanguis/genética , Técnicas de Tipagem Bacteriana , Mapeamento Cromossômico , Cromossomos Bacterianos/genética , Estudos de Coortes , Meios de Cultura , Impressões Digitais de DNA , DNA Bacteriano/análise , DNA Intergênico/genética , Variação Genética , Genótipo , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Fenótipo , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Análise de Sequência de DNA , Estatística como Assunto , Streptococcus sanguis/classificação
20.
Acta Radiol ; 45(6): 664-8, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15587426

RESUMO

We present two cases of persistent primitive trigeminal artery (PPTA) associated with a giant aneurysm originating at the opening of the PPTA on the internal carotid artery (ICA). In one case, opening of the PPTA occurred 4 months after balloon occlusion of the ICA, when a giant aneurysm located at the cavernous segment of the ICA was being treated. The PPTA was occluded successfully using a Guglielmi detachable coil (GDC). A vertebral artery approach was taken. This is the first report of the opening of a PPTA associated with contrast filling of the aneurysm after balloon occlusion of the parent artery. The possibility of contrast filling of the aneurysm via potential PPTA should therefore be considered in the event of an ICA aneurysm with parent artery occlusion.


Assuntos
Artéria Carótida Interna/anormalidades , Aneurisma Intracraniano/etiologia , Malformações Arteriovenosas Intracranianas/terapia , Oclusão com Balão , Angiografia Cerebral , Embolização Terapêutica , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Malformações Arteriovenosas Intracranianas/complicações , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Pessoa de Meia-Idade
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