RESUMO
AIM: We design a feasibility study to obtain a set of metabolic-hemodynamic habitats for tackling tumor spatial metabolic patterns with hemodynamic information. MATERIALS AND METHODS: Preoperative data from 69 high-grade gliomas (HGG) patients with subsequent histologic confirmation of HGG were prospectively collected (January 2016 to March 2020) after concurrent chemoradiotherapy (CCRT). Four vascular habitats were automatically segmented by multiparametric magnetic resonance imaging (MRI). The metabolic information, either at enhancing or edema tumor regions, was obtained by two neuroradiologists. The relative habitat volumes were used for weight estimation procedures for computing the coefficients of a linear regression model using weighted least squares (WLS) for metabolite semiquantifications (i.e. the Cho/NAA ratio and the Cho/Cr ratio) at vascular habitats. Multivariate Cox proportional hazard regression analyses are used to obtain the odds ratio (OR) and develop a nomogram using weighted estimators corresponding to each covariate derived from Cox regression coefficients. RESULTS: There was a strongly correlation between perfusion indexes and the Cho/Cr ratio (rCBV, r=0.71) or Cho/NAA ratio (rCBV, r=0.66) at high-angiogenic enhancing tumor habitats (HAT) habitat. Compared isocitrate dehydrogenase (IDH) mutation to their wild type, the IDH wild type had significantly decreased Cho/Cr ratio (IDH mutation: Cho/Cr ratio = 2.44 ± 0.33, IDH wildtype: Cho/Cr ratio = 2.66 ± 0.36, p=0.02) and Cho/NAA ratio (IDH mutation: Cho/Cr ratio = 4.59 ± 0.61, IDH wildtype: Cho/Cr ratio = 4.99 ± 0.66, p=0.022) at the HAT. The C-index for the median progression-free survival (PFS) prediction was 0.769 for the Cho/NAA nomogram and 0.747 for the Cho/Cr nomogram through 1000 bootstrapping validation. CONCLUSIONS: Our findings suggest that spatial metabolism combined with hemodynamic heterogeneity is associated with individual PFS to HGG patients post-CCRT.
Assuntos
Neoplasias Encefálicas , Estudos de Viabilidade , Glioma , Hemodinâmica , Intervalo Livre de Progressão , Humanos , Glioma/diagnóstico por imagem , Glioma/patologia , Glioma/terapia , Feminino , Masculino , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Pessoa de Meia-Idade , Hemodinâmica/fisiologia , Adulto , Estudos Prospectivos , Idoso , Imageamento por Ressonância Magnética Multiparamétrica/métodosRESUMO
Objective: To summarize the clinical characteristics of patients with Takotsubo syndrome (TTS) from China and compare these features with patients from Europe/North America. Methods: We reviewed case reports published between 1990 and 2020 with the key words of "Takotsubo syndrome" "stress cardiomyopathy" "apical balloon syndrome" and "broken heart syndrome", in Wanfang, CNKI, Pubmed and Web of Science databases, and 1 294 articles were identified, including 128 articles reporting 163 cases in China and 1 166 articles reporting 1 256 cases in Europe/North America. The characteristics of demographics, triggers, symptoms, electrocardiogram, echocardiography, left ventriculogram,coronary angiography, treatment and prognosis were analyzed and compared between Chinese and European/North American cases. Results: A total of 1 294 articles (1 419 cases: 163 from China, 1 256 from Europe/North America) were included in the final analysis. The characteristics of Chinese cases included: (1) demographic:the age was (59.6±16.9) years, which was similar with that of European/North American ((59.7±17.4) years, P=0.90), and female accounting for 78.5% (128/163), which was lower than that of European/North American (85.4% (1 073/1 256), P=0.02). (2) Triggers:mental triggers accounted for 48.5% (79/163), physical triggers accounted for 43.6% (71/163), and no triggers accounted for 7.9% (13/163), respectively. Compared with Europe/North America, the ratio of patients with mental triggers was higher in China, while the ratio of patients with physical triggers and no triggers was lower (P<0.05). (3) Symptoms: chest pain (52.8% (86/163)), chest tightness (35.0% (57/163)), shortness of breath (33.1% (54/163)), dizziness (16.0% (26/163)), sweating (15.3% (25/163)), palpitations (12.3% (20/163)), syncope (9.2% (15/163)) abdominal pain/diarrhea (8.6% (14/163)), hypotension (7.4% (12/163)), and fatigue (1.2% (2/163)) were illustrated in sequence. Compared with patients in Europe/North America, the ratio of patients with chest tightness, dizziness, sweating, palpitations, abdominal pain/diarrhea was higher in Chinese patients, while the ratio of patients with hypotension was lower in Chinese patients (P<0.05). (4) Electrocardiogram: main manifestations were myocardial ischemia symptoms, such as ST-segment elevation (63.8% (104/163)), T wave inversion (46.0% (75/163)), ST-segment depression (8.6% (14/163)). Compared with European/North American, the ratio of patients with ST-segment elevation, T wave inversion, and atrioventricular block was higher in Chinese patients (P<0.05). (5) Echocardiography and imaging:apical dyskinesia (59.5% (97/163)) and apical/left ventricular bulbar dilation (36.2%(59/163)) dominated the echocardiography findings. Compared with European/North American, the ratio of patients with apical dyskinesia, apical/left ventricular bulbar dilation, and mitral regurgitation was higher in Chinese patients, while the ratio of patients with dyskinesia in other parts and left ventricular ejection fraction<50% was lower in Chinese patients (P<0.05). Left ventricular angiography showed 36.2% (59/163) of apical dyskinesia in Chinese patients, which was higher than that reported in European/North American patients, and 38.7% (63/163) of apical/left ventricular bulbar dilation was reported in Chinese patients, which was similar to that reported in European/North American patients. Coronary angiography showed percent of no stenosis or stenosis less than 50% was 87.1% (142/163), which was similar to that reported in European/North American patients (P>0.05). The typical type of TTS accounted for 96.3% (157/163), which was significantly higher than that reported in European/ American patients, while the ratio of basal type and midventricular type was lower (P<0.01). (6) Treatment and prognosis:the applied drugs in China were listed in order as following, ß-blockers (41.1% (67/163)), antiplatelet agents (37.4%(61/163)), ACEI/ARB (36.2%(59/163)), anticoagulants (27.0%(44/163)), diuretics (19.6% (32/163)), etc. Compared with Europe/North America, the ratio of antiplatelet agents, anticoagulants, statins, diuretics, and nitrates use was higher in China (P<0.05), while the use of oxygen therapy and IABP was similar (P>0.05). The hospital mortality in China was 5.5% (9/163), during 1-year follow-up the recurrence rate was 3.7% (6/163) and the mortality was 0. The prognosis was similar with that in Europe/North America. Conclusions: Compared with TTS cases in Europe/North America, TTS cases in China also occur usually in middle-aged and elderly women, most of whom have mental/physical triggers and typical imaging manifestations, followed by a low hospital mortality rate and recurrence rate.
Assuntos
Discinesias , Hipotensão , Cardiomiopatia de Takotsubo , Dor Abdominal/complicações , Adulto , Idoso , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Anticoagulantes , Arritmias Cardíacas/complicações , China/epidemiologia , Diuréticos , Tontura/complicações , Discinesias/complicações , Eletrocardiografia , Europa (Continente)/epidemiologia , Feminino , Humanos , Hipotensão/complicações , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária , Volume Sistólico , Cardiomiopatia de Takotsubo/epidemiologia , Cardiomiopatia de Takotsubo/etiologia , Função Ventricular EsquerdaRESUMO
AIMS: Arbuscular mycorrhizal fungi (AMF) are symbiotic partners of many invasive plants, however, it is still unclear how AMF contribute to traits that are important for the successful invasion of their host and how environmental factors, such as nutrient conditions, influence this. This study was to explore the effects of Glomus versiforme (GV) and Glomus mosseae (GM) on the growth and disease resistance of the invasive plant Wedelia trilobata under different nutrient conditions. METHODS AND RESULTS: We found that GV and GM had higher root colonization rates resulting in faster W. trilobata growth under both low-N and low-P nutrient conditions compared to the normal condition. Also, the colonization of W. trilobata by GV significantly reduced the infection area of the pathogenic fungus Rhizoctonia solani under low-N conditions. CONCLUSIONS: These results demonstrated that AMF can promote the growth and pathogenic defence of W. trilobata in a nutrient-poor environment, which might contribute to their successful invasion into certain type of habitats. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, we report for the first time that AMF can promote growth and disease resistance of W. trilobata under nutrient-poor environment, which contribute to a better understanding of plant invasion.
Assuntos
Resistência à Doença , Espécies Introduzidas , Micorrizas/fisiologia , Wedelia/crescimento & desenvolvimento , Wedelia/microbiologia , Fungos/fisiologia , Nutrientes/deficiência , Raízes de Plantas/microbiologia , Rhizoctonia/patogenicidade , Rhizoctonia/fisiologia , Simbiose , Wedelia/imunologiaRESUMO
AIM: To effectively make high-quality silage in hot and humid area. METHODS AND RESULTS: The natural lactic acid bacteria (LAB) strains CZ149, XH358, XH753 and XH761 isolated from corn and Napier grass were screened by the potential of low pH growth and high lactic acid production, and their effect on silage quality, aerobic stability and aflatoxin B1 production of whole-crop corn was also studied in Sichuan, China. Four selected strains were Gram-positive and catalase-negative, rod-shaped strains that are able to grow at pH 3·5 and at 45°C. Strains CZ149, XH358, XH753 and XH761 were identified as Lactobacillus plantarum, L. salivarius, L. rhamnosus and L. paracasei, respectively. After 60 days of fermentation, all LAB strains showed no significant relationship with the quality of corn silage, whereas the lowest aflatoxin B1 and lactic-to-acetic ratio were detected in strain XH753-treated silage. Strain CZ149-treated silage showed worse aerobic stability and higher aflatoxin B1 concentration than control, whereas strain XH753-treated silage had better aerobic stability and lowest aflatoxin B1 concentration after aerobic exposure in hot and humid condition for 5 days. CONCLUSIONS: The three L. plantarum strains used in this study are not suitable as inoculants for local whole-crop corn silage, whereas L. rhamnosus 753 could prolong the aerobic stability and inhibit the accumulation of aflatoxin B1 at hot and humid condition. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides new information of LAB inoculants for corn silage in hot and humid areas. Especially, a screened strain of Lactobacillus rhamnosus 753 can be used as a candidate strains to make high-quality silage in tropical and subtropical areas.
Assuntos
Aflatoxina B1/análise , Lactobacillales/isolamento & purificação , Lactobacillales/fisiologia , Silagem/microbiologia , China , Fermentação , Temperatura Alta , Concentração de Íons de Hidrogênio , Ácido Láctico/metabolismo , Lactobacillales/classificação , Lactobacillales/metabolismo , Pennisetum/microbiologia , Silagem/análise , Especificidade da Espécie , Zea mays/microbiologiaRESUMO
PURPOSE: Somatostatin analogs (SSAs) are considered one of the most effective medical treatments for patients with growth hormone-secreting pituitary adenomas (GH-PAs). The postoperative electron microscopy (EM) pathological subtype and SSTR2 expression in the tumor are the most established predictors of patient response to SSA therapy. The aim of this study was to evaluate how will magnetic resonance spectroscopy (MRS) measurements before surgery predict the EM pathological subtypes and SSTR2 expression of tumors, and thereby serve as an indicator for the therapeutic sensitivity to SSAs of patients with GH-PAs. METHODS: Eighteen patients with GH pituitary macroadenomas who underwent transsphenoidal surgery were included in this retrospective study. The preoperative MRS data and T2 signal intensity were obtained from patients by 1.5 T MR spectroscopy of the sellar mass. The EM pathological subtypes of tumors were determined after surgery through examination of cell granulations. The expressions of somatostatin receptor 2 (SSTR2), SSTR5, P21, P27, and Ki-67 were evaluated by immunohistochemistry. RESULTS: The MRS parameters that were found to significantly predict the EM pathological subtypes of tumors, as calculated by the receiver operating characteristic curve, were the choline (Ch) value at 3140.5 MR units (sensitivity 69.2%, specificity 100%) and the choline/creatine (Ch/Cr) ratio at 1.27 (sensitivity 92.3%, specificity 100%). Further, the Ch/Cr ratio, but not other MRS data, was shown to negatively correlate with the expression of SSTR2 (P = 0.02). The Ch/Cr ratio was also found to positively correlate with the Ki-67 value (P < 0.05) and T2 signal (P < 0.05), but not with other factors that were examined in this study. Moreover, the Ch/Cr ratio could predict the EM pathological subtypes of tumors with an accuracy of 83.3% (5/6) for patients with an isointense T2 signal. CONCLUSION: The Ch/Cr ratio by MRS could effectively predict the tumor subtype and was significantly correlated with the expression of SSTR2, which was consistent with other predictors. It was also able to distinguish the patients with isointense T2 signals. Our results provide a potentially new and non-invasive method to predict the response to SSAs in patients with GH pituitary macroadenomas.
Assuntos
Adenoma/patologia , Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , Antagonistas de Hormônios/farmacologia , Espectroscopia de Ressonância Magnética/métodos , Cuidados Pré-Operatórios , Receptores de Somatostatina/metabolismo , Somatostatina/análogos & derivados , Adenoma/tratamento farmacológico , Adenoma/metabolismo , Adenoma/cirurgia , Adulto , Idoso , Biomarcadores/análise , Feminino , Seguimentos , Adenoma Hipofisário Secretor de Hormônio do Crescimento/tratamento farmacológico , Adenoma Hipofisário Secretor de Hormônio do Crescimento/metabolismo , Adenoma Hipofisário Secretor de Hormônio do Crescimento/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos RetrospectivosRESUMO
BACKGROUND: Atopic dermatitis (AD) is the most common skin disorder in infancy. However, the diagnosis and definite significance of infantile AD remains a debated issue. OBJECTIVE: To analyse the phenotypes of AD in infancy, to establish diagnostic criteria and to estimate the prevalence of this condition in China. METHODS: This is a multicentric study, in which 12 locations were chosen from different metropolitan areas of China. Following careful and complete history-taking and skin examination, the definite diagnosis of AD was made and the severity based on the SCORAD index was determined by local experienced dermatologists. Based on the detailed phenotyping, the major and representative clinical features of infantile AD were selected to establish the diagnostic criteria and evaluate their diagnostic efficacy. RESULTS: A total of 5967 infants were included in this study. The overall point prevalence of AD was 30.48%. The infantile AD developed as early as at the second month of life, and its incidence peaked in the third month of life at 40.81%. The proportion of mild, moderate and severe AD was 67.40%, 30.57% and 2.03%, respectively. The most commonly seen manifestations in the infantile AD were facial dermatitis (72.07%), xerosis (42.72%) and scalp dermatitis (27.93%). We established the novel diagnostic criteria of infants, which included: (i) onset after 2 weeks of birth; (ii) pruritus and/or irritability and sleeplessness comparable with lesions; and (iii) all two items above with one of the following items can reach a diagnosis of AD: (i) eczematous lesions distributed on cheeks and/or scalp and/or extensor limbs, and (ii) eczematous lesions on any other parts of body accompanied by xerosis. CONCLUSIONS: In China, the prevalence of AD in infancy is 30.48% according to clinical diagnosis of dermatologists. The novel Chinese diagnostic criteria for AD in infants show a higher sensitivity and comparable specificity.
Assuntos
Dermatite Atópica/diagnóstico , Fenótipo , China/epidemiologia , Dermatite Atópica/epidemiologia , Feminino , Humanos , Lactente , Masculino , PrevalênciaRESUMO
Objective: To investigate the effects of 3-methyladenine on airway inflammation, airway hyperresponsiveness and mucus secretion in asthmatic mice, and to explore its mechanism. Methods: C57BL/6J female mice were randomly divided into normal control group (PBS), OVA group(OVA), OVA with 3-methyladenine group (OVA+3-MA), and OVA with 4-phenylbutyrate group (OVA+4-PBA). OVA group, OVA+3-MA group and OVA+4-PBA groups were all sensitized and challenged with OVA to establish asthmatic models, while PBS group was given PBS as a control. At 2 h before challenge, OVA+3-MA group was intraperitoneally injected with 3-methyladenine, and OVA+4-PBA group was intraperitoneally injected with 4-phenylbutyrate. Airway hyperresponsiveness, eosinophils, and pathological changes of pulmonary tissue (hematoxylin-eosin, HE staining) were measured to confirm the establishment of asthmatic models. Sections of pulmonary tissue were also stained with Masson and PAS. The expression level of LC3B was measured by immunofluorescence and Western blot. The Beclin1, Muc5ac, Atf6, Chop and Bip proteins in lung tissues were detected by Western blot. Results: The Penh value, and eosinophils in BALF in OVA group was significantly increased compared with PBS group (P<0.05). The Penh value in OVA+3-MA group and OVA+4-PBA group were significantly decreased compared with the OVA group at the concentration of 6.25 g/L, 12.50 g/L, 25.00 g/L, and 50.00 g/L of methacholine (all the P<0.05), and the eosinophils were also significantly decreased compared with the OVA group (P<0.05). Pulmonary histology revealed that OVA group showed high levels of inflammatory cell infiltration of bronchi and lung vessels, alveolar septal thickening, structural destruction, smooth muscle thickening, collagen deposition, and goblet cell hyperplasia. The levels of inflammatory cell infiltration of bronchi and lung vessels, alveolar septal thickening, structural destruction, smooth muscle thickening, collagen deposition, and goblet cell hyperplasia in OVA+3-MA group and OVA+4-PBA group were significantly lower than the OVA group, while the PBS group was normal. Compared with PBS group, the expression of LC3 â ¡/â , Beclin1, Muc5ac, Atf6, Chop and Bip proteins in lung tissues in the OVA group were significantly increased (1.09±0.04 vs 0.34±0.09, P<0.05; 0.18±0.01 vs 0.06±0.01, P<0.05; 1.90±0.38 vs 0.46±0.11, P<0.05; 1.67±0.18 vs 0.41±0.08, P<0.05; 2.96±0.45 vs 1.11±0.10, P<0.05; 2.07±0.34 vs 0.49±0.17, P<0.05, respectively). Compared with the OVA group the expression of LC3 â ¡/â , Beclin1, Muc5ac, Atf6, Chop and Bip proteins in lung tissues in the OVA+3-MA group and OVA+4-PBA group were significantly decreased (0.46±0.07 vs 1.09±0.04, 0.63±0.03 vs 1.09±0.04, both P<0.05; 0.11±0.02 vs 0.18±0.01, 0.12±0.02 vs 0.18±0.01, both P<0.05; 0.72±0.22 vs 1.90±0.38, 0.57±0.13 vs 1.90±0.38, both P<0.05; 1.06±0.12 vs 1.67±0.18, 1.02±0.12 vs 1.67±0.18, both P<0.05; 1.67±0.21 vs 2.96±0.45, 1.10±0.15 vs 2.96±0.45, both P<0.05; 1.03±0.11 vs 2.07±0.34, 0.97±0.10 vs 2.07±0.34, both P<0.05). Conclusion: 3-MA was shown to inhibit airway inflammation, airway hyperresponsiveness and mucus secretion in mice with bronchial asthma, and the mechanism may be related to inhibiting autophagy, and then inhibiting endoplasmic reticulum stress.
Assuntos
Adenina , Asma , Inflamação , Pulmão , Muco , Animais , Feminino , Camundongos , Adenina/administração & dosagem , Adenina/análogos & derivados , Asma/metabolismo , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Pulmão/efeitos dos fármacos , Pulmão/patologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Muco/efeitos dos fármacos , Muco/metabolismoRESUMO
Objective: To summarize the clinical characteristics of patients with cleidocranial dysplasia (CCD) and analyze their treatment methods. Methods: From January 2000 to December 2020, patients with CCD who completed comprehensive treatment in the Department of Orthodontics and the First Dental Clinic, School and Hospital of Stomatology, China Medical University were retrospectively analyzed. A total of 14 CCD patients [7 males and 7 females, aged (16.1±4.5) years] were collected. There were 153 impacted permanent teeth in this study. In addition to the teeth that needed to be extracted due to special conditions, 147 impacted teeth were pulled into the dentition using closed traction. Patients were divided into adolescent group (≥12 years and<18 years, 10 patients) and adult group (≥18 years, 4 patients). Failure rate of traction was compared between the two groups. Factors affecting the success rate of closed traction such as vertical position of teeth (high, middle and low) and horizontal position of the teeth (palatal, median and buccal) were analyzed. Results: The incidence of maxillary impacted teeth [69.3% (97/140)] was higher than that of mandibular impacted teeth [40% (56/140)]. The difference was statistically significant (χ2=24.22, P<0.001). The supernumerary teeth were mainly located in the premolar area 61.4% (21/44), and most of them were in the palatal region of the permanent teeth 95.5% (42/44). They were generally located at the same height or the occlusal side of the corresponding permanent teeth. The success rate of closed traction was 93.9% (138/147). The success rate in the adolescent group [98.2% (108/110)] was higher than that in the adult group [81.1% (30/37)], and the difference was significant (χ2=14.09, P<0.05). Failure after closed traction of 9 teeth was found totally, including 7 second premolars. The success rate of traction in impacted second premolars at different vertical (χ2=11.44, P<0.05) and horizontal (χ2=9.71, P<0.05) positions in alveolar bone was different significantlly. The success rates of the second premolars were high (15/16), middle (12/13), low (2/7), and lingual palatine (10/17), median (19/19), lip-buccal (0/0), respectively. Conclusions: The closed traction of impacted teeth in patients with CCD was effective, and the age was the main variable affecting the outcome. The success rate of traction in impacted second premolars located in low position vertically or in palatal position was low, which required close observation during treatment.
Assuntos
Displasia Cleidocraniana , Dente Supranumerário , Adolescente , Adulto , Dente Pré-Molar , Criança , Displasia Cleidocraniana/terapia , Feminino , Humanos , Masculino , Mandíbula , Estudos Retrospectivos , Dente Supranumerário/cirurgia , Adulto JovemRESUMO
The endoscopic transethmoidal approach is favored for the lack of external scars, a wide field of view, and rapid recovery time. But the effect of iatrogenic trauma should not be ignored due to the removal of the uncinate process and anterior and posterior ethmoidal sinus. Anatomically, the optic nerve is close to the sphenoid sinus and Onodi cell. In order to preserve the uncinate process and ethmoidal sinus, we perform endoscopic transsphenoidal optic canal decompression (ETOCD), which is less invasive. However, the anatomy of sphenoid sinus is quite variable, and the anatomical landmarks are rare. Therefore, identifying the position of optic canal is particularly important during surgery. To solve this, we use a postprocessing technique to identify the position of the optic nerve and internal carotid artery on the sphenoid sinus wall. Our results find that VA in 13 patients improved, with a total improve rate of 59.1%. No serious complications were found. We also found that the length of optic canal is different and the medial wall of the optic canal was the longest (p < 0.05). The middle section of the optic canal is the narrowest, which was significantly different from cranial mouth and orbital mouth (p < 0.05). We assumed that decompression may not require removal of all medial wall. If we remove the length of the shortest wall on the medial wall of the optic canal, the compression may be relieved. Thus, ETOCD was a feasible, safe, effective, and less-invasive approach for patients with TON. The CT postprocessing imaging facilitated recognition of the optic canal during surgery. The decompression length of the medial wall may not need to be completely removed, especially near the cranial mouth.
RESUMO
Based on the dominance of cellular senescence over immortality, immortal human cell lines have been assigned to four complementation groups for indefinite division. Human chromosomes carrying senescence genes have been identified, including chromosome 4. We report the cloning and identification of a gene, mortality factor 4 (MORF 4), which induces a senescent-like phenotype in immortal cell lines assigned to complementation group B with concomitant changes in two markers for senescence. MORF 4 is a member of a novel family of genes with transcription factor-like motifs. We present here the sequences of the seven family members, their chromosomal locations, and a partial characterization of the three members that are expressed. Elucidation of the mechanism of action of these genes should enhance our understanding of growth regulation and cellular aging.
Assuntos
Senescência Celular/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Sequência de Bases , Divisão Celular/genética , Linhagem Celular , Núcleo Celular/metabolismo , Expressão Gênica , Teste de Complementação Genética , Humanos , Dados de Sequência Molecular , Família Multigênica , Sondas de Oligonucleotídeos/genética , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/metabolismoRESUMO
Tip60 was originally isolated as a Tat interactive protein. It was subsequently shown that Tip60 had histone acetyltransferase (HAT) activity. In studies to understand gene-expression regulation that might involve HAT activity, we PCR-amplified Tip60 from a human heart marathon-ready cDNA library. As a result, we identified an alternatively spliced form of Tip60, Tip60beta (we refer to the previously cloned Tip60 as Tip60alpha). Tip60beta cDNA is slightly smaller than Tip60alpha, and sequencing indicates that there is a deletion of 156 bp in the coding region of the gene. The predicted Tip60beta protein therefore lacks 52 amino acids when compared with Tip60alpha. The Tip60alpha gene is encoded by 14 exons, and Tip60beta is an alternatively spliced form resulting from the exclusion of exon 5 during the splicing process. Exon 5 encodes a proline-rich region that is known to be important for protein-protein interaction. Tip60beta is expressed in a variety of human tissues and cell lines, and the protein is present in both the nucleus and cytoplasm in contrast to Tip60alpha, which is entirely nuclear. The results suggest that Tip60beta may have functions additional to those of Tip60alpha in cells and tissues.
Assuntos
Acetiltransferases , Processamento Alternativo , Proteínas/genética , Sequência de Aminoácidos , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Citoplasma/metabolismo , DNA Complementar/química , DNA Complementar/genética , DNA Recombinante/genética , DNA Recombinante/metabolismo , Expressão Gênica , Células HeLa , Histona Acetiltransferases , Humanos , Lisina Acetiltransferase 5 , Camundongos , Microscopia de Fluorescência , Dados de Sequência Molecular , Isoformas de Proteínas/genética , RNA/genética , RNA/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Distribuição Tecidual , Células Tumorais CultivadasRESUMO
Genetic analyses of replicative senescence have revealed the dominance of the senescent phenotype since whole cell fusion of normal with immortal cells yields hybrids having limited division potential. We exploited the recessive nature of immortality by fusing different immortal human cell lines with each other and identified four complementation groups for indefinite division. This allowed for a focussed approach involving microcell mediated chromosome transfer that led to the implication of chromosomes 1, 4 and 7 as loci for cell senescence genes. More recently we have cloned the gene on chromosome 4, MORF 4. It is a member of a family of genes with motifs suggestive of transcriptional regulators. Characterization of this novel gene family should lend further insights into the phenomenon of replicative cell senescence.
Assuntos
Senescência Celular/genética , Animais , Fusão Celular , Humanos , Transdução de Sinais , Telomerase/metabolismo , Telômero/fisiologiaRESUMO
The pathophysiological, biochemical, histological, ultrastructural, and immunohistochemical characters of a case of malignant pancreatic islet cell tumor with watery diarrhea syndrome were carefully investigated. Four hormones or mediators--somatostatin (SST), vasoactive intestinal peptide (VIP), serotonin, and prostaglandin E--were markedly elevated in the circulation. The diagnosis was further confirmed by exploratory laparotomy and autopsy. The contents of SST and VIP in tumor tissues were very high. Gel chromatography of tumor extract revealed single peaks for both SST and VIP. Immunohistochemical studies of tumor tissues showed numerous immunoreactive cells to anti-SST, moderate amount of VIP-positive cells, and a few hCG-, insulin-, and glucagon-positive cells. In conclusion, this is an unusual case of Verner-Morrison syndrome in which three kinds of bioactive hormones or mediators were simultaneously secreted; peptides, amine, and prostaglandin.
Assuntos
Adenoma de Células das Ilhotas Pancreáticas/metabolismo , Hormônios/metabolismo , Neoplasias Pancreáticas/metabolismo , Vipoma/metabolismo , Adulto , Histocitoquímica , Humanos , Masculino , Neoplasias Pancreáticas/ultraestrutura , Prostaglandinas E/metabolismo , Serotonina/metabolismo , Somatostatina/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo , Vipoma/ultraestruturaRESUMO
Dot blot showed that the expression of proto-oncogene c-fos was inhibited in lymphocytes from old mice (20-24 months). In order to measure the effect of aging on signal transduction, we separated T cells by passage of spleen lymphocytes through long nylon fiber columns. Con A-induced [3H] TdR incorperation in cells from old mice was lower than that from young mice (2 months). The maximum level of [3H]TdR incorperation of old mouse T cells was only 22% of that of young mouse T cells. When T cells were stimulated with the combination of a phorber ester (PMA) and a calcium ionophore (ionomycin), [3H]TdR incorperation remained depressed in old mouse T cells. Further, cytosolic free calcium level was measured by monitoring fluoresence intensity in fura-2/AM loaded T cells. At 10 minutes after con A stimulation, the concentration of cytosolic free calcium ([Ca2+]) in old mouse T cells elevated to 273 x 10(-9)mol/L, while [Ca2+] in young mouse T cells markedly increased to 637 x 10(-9)mol/L. When T cells were stimulated with the combination of PMA and ionomycin, at 7 minutes, [Ca2+] in old mouse T cells elevated to 790 x 10(-9)mol/L, while [Ca2+] in young mouse T cells markedly increased up to 2190 x 10(-9)mol/L.
Assuntos
Envelhecimento/metabolismo , Cálcio/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Linfócitos T/metabolismo , Animais , Transporte Biológico Ativo , Expressão Gênica , Genes fos , Ionomicina , Camundongos , Camundongos Endogâmicos C57BL , Transdução de SinaisRESUMO
Bone marrow hemopoietic microenvironment plays an important role in the incidence and development of leukemia. Studies using normal bone marrow stromal cells (BMSCs) and an established stromal cell line, have shown that the leukemic cell cycle can be arrested in the G0/G1 phase in BMSCs, although the mechanism is still unclear. We performed this study to determine the effect of primary cultured leukemic BMSCs on the cell cycle distribution of Jurkat cells. Normal and leukemic BMSCs were isolated for culture to create a hematopoietic microenvironment simulating bone marrow in vitro. The normal and leukemic BMSCs induced cell cycle arrest of Jurkat cells in the G0/G1 phase. Suppression subtractive hybridization revealed differential gene expression after the co-culture of cells with normal and leukemic BMSCs. Jurkat cells showed upregulated expression of genes involved in cell cycle control CR6 interacting factor 1 (CRIF1). Reverse transcriptase polymerase chain reaction results also showed increased CRIF1 mRNA levels in Jurkat cells co-cultured with either normal BMSCs or leukemic BMSCs compared with a suspension culture group: 5.16 ± 0.75, 6.13 ± 0.63 versus 3.02 ± 0.32, respectively (P < .05). These results indicated cell cycle arrest of Jurkat cells in the G0/G1 phase to be induced by primary cultured leukemic BMSCs associated with increased expression of CRIF1 by leukemic cells.
Assuntos
Células da Medula Óssea/patologia , Proteínas de Ciclo Celular/fisiologia , Ciclo Celular/fisiologia , Leucemia/patologia , Proteínas Nucleares/fisiologia , Células Estromais/patologia , Sequência de Bases , Técnicas de Cocultura , Primers do DNA , Humanos , Células Jurkat , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
We have measured the vibrational excitation probability (Pv) of HCl incident on a Au(111) surface at kinetic energies (Ei) of 0.59 eV to 1.37 eV and surface temperatures (Ts) of 273 K to 1073 K. For all energies, the slope of the Pv as a function of Ts exhibits a sharp increase above Ts approximately 800 K. We show this change in slope and the threshold behavior of Pv to be consistent with a change in excitation mechanism from an electronically adiabatic mechanical mechanism to an electronically nonadiabatic mechanism involving excited electron-hole pairs.
RESUMO
We propose a new image encryption algorithm based on a generalized fractional Fourier transform, to which we refer as a multifractional Fourier transform. We encrypt the input image simply by performing the multifractional Fourier transform with two keys. Numerical simulation results are given to verify the algorithm, and an optical implementation setup is also suggested.
RESUMO
We propose a wave-front filtering concept of wavelet optics and present its associated theory of wavelet optics. We analyze the filtering phenomenon of wavelet optics at the spatial-frequency domain-multiscale edge detection and multiscale feature recognition-using the theory, and we also perform the analysis with the Mexican-hat wavelet and the Haar wavelet. By use of our theory, information is obtained from an optical image that is processed multiscalely and delicately by stretching and translation of the factors. With this technique it is possible to perform real-time programming in information processing in a mixed optical system.
RESUMO
The (0, 0), (1, 0), (2, 0), (3, 0), and (4, 0) bands of the C(3)Delta-X(3)Delta transition of TiS, between 743-863 nm, were studied using the technique of laser vaporization/reaction with supersonic cooling and laser-induced fluorescence (LIF) spectroscopy. The linewidth of the LIF spectrum obtained was about 250 MHz. The P, Q, and R branches of each DeltaOmega = 0 subband were observed. A merged least-squares fit of the measured line positions yielded molecular parameters of the v = 0-4 levels of the C(3)Delta state and the v = 0 level of the X(3)Delta state. Copyright 1999 Academic Press.
RESUMO
We report here the cloning and characterization of a novel KRAB zinc finger gene, ZFQR, which has eight tandemly repeated zinc fingers, a complete KRAB box at the N-terminal region, and a unique C-terminal sequence. It is expressed in a variety of human tissues, and mRNA levels are upregulated in nondividing senescent and quiescent human fibroblasts. Overexpression of the protein in quiescent cells stimulated with serum growth factors results in inhibition of entry into the cell cycle. The latter activity is lost when the N-terminal KRAB domain is deleted. The KRAB domain is also required for the transcriptional repression activity of ZFQR and in maintaining association of the protein with the nuclear matrix. The gene has been mapped to human chromosome 19q13.4. The association of ZFQR with the nuclear matrix, transcriptional repression activity, increased expression in senescent and quiescent cells, and the ability to inhibit quiescent cells stimulated with growth factors from entering the cell cycle suggests a role for ZFQR in the maintenance of the nondividing state of normal human cells.