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Objective: To explore the clinical changes in levels of the new clinical marker serum hepatitis B virus (HBV) pregenomic RNA (pgRNA) in patients with chronic hepatitis B (CHB) with long-term antiviral therapy. Methods: 100 CHB cases who were initially treated with nucleos(t)ide analogues (NAs) at Peking University First Hospital were included. The levels of alanine aminotransferase (ALT), HBV DNA, hepatitis B e-antigen (HBeAg), and hepatitis B surface antigen (HBsAg) during the follow-up period were measured. The TaqMan-based real-time quantitative PCR method was used to detect serum HBV pgRNA levels. The independent sample t-test and Mann-Whitney U test were used to compare continuous variables between groups, while Pearson's χ (2) test and Fisher's exact test were used to compare categorical variables. Results: HBV pgRNA levels decreased significantly in patients who developed virological responses at 48 weeks (n = 54) during subsequent treatment compared to those who did not (n = 46). The HBV pgRNA level was lower in HBeAg-positive patients than in HBeAg-negative patients (P < 0.05 or P < 0.01). Patients with higher HBV DNA and HBeAg-positivity levels at baseline had a higher HBV pgRNA level following antiviral therapy. There was no statistically significant difference in HBV pgRNA levels in patients with different HBV pgRNA levels at baseline after antiviral therapy. There was no correlation between serum HBV pgRNA and HBsAg at baseline, but there was a correlation after long-term antiviral therapy, while there was a weak correlation between HBV pgRNA and HBsAg at the fifth and ninth years of antiviral therapy (r = 0.262, P = 0.031; r = 0.288, P = 0.008). Conclusion: HBV pgRNA levels were higher with higher HBV activity in CHB patients with long-term antiviral therapy.
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Hepatitis B Crónica , Humanos , Virus de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B , Antígenos e de la Hepatitis B , ADN Viral , Antivirales/uso terapéutico , ARNRESUMEN
Objective: To investigate the efficacy of chitinase-3-like protein 1 (CHI3L1) and Golgi protein 73 (GP73) in the diagnosis of cirrhosis and the dynamic changes of CHI3L1 and GP73 after HCV clearance in patients with chronic hepatitis C (CHC) treated with direct-acting antiviral drugs (DAAs). The comparison of continuous variables of normal distribution were statistically analyzed by ANOVA and t-test. The comparison of continuous variables of non-normal distribution were statistically analyzed by rank sum test. The categorical variables were statistically analyzed by Fisher's exact test and χ(2) test. Correlation analysis was performed using Spearman correlation analysis. Methods: Data of 105 patients with CHC diagnosed from January 2017 to December 2019 were collected. The receiver operating characteristic curve (ROC curve) was plotted to study the efficacy of serum CHI3L1 and GP73 for the diagnosis of cirrhosis. Friedman test was used to compare CHI3L1 and GP73 change characteristics. Results: The areas under the ROC curve for CHI3L1 and GP73 in the diagnosis of cirrhosis at baseline were 0.939 and 0.839, respectively. Serum levels of CHI3L1 and GP73 in the DAAs group decreased significantly at the end of treatment compared with baseline [123.79 (60.25, 178.80) ng/ml vs. 118.20 (47.68, 151.36) ng/ml, P = 0.001; 105.73 (85.05, 130.69) ng/ml vs. 95.52 (69.52, 118.97) ng/ml, P = 0.001]. Serum CHI3L1 and GP73 in the pegylated interferon combined with ribavirin (PR) group were significantly lower at the end of 24 weeks of treatment than the baseline [89.15 (39.15, 149.74) ng/ml vs. 69.98 (20.52, 71.96) ng/ml, P < 0.05; 85.07 (60.07, 121) ng/ml vs. 54.17 (29.17, 78.65) ng/ml, P < 0.05]. Conclusion: CHI3L1 and GP73 are sensitive serological markers that can be used to monitor the fibrosis prognosis in CHC patients during treatment and after obtaining a sustained virological response. Serum CHI3L1 and GP73 levels in the DAAs group decreased earlier than those in the PR group, and the serum CHI3L1 levels in the untreated group increased compared with the baseline at about two years of follow-up.
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Hepatitis C Crónica , Humanos , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/tratamiento farmacológico , Antivirales/uso terapéutico , Proteínas de la Membrana/metabolismo , Cirrosis Hepática/diagnóstico , Fibrosis , BiomarcadoresAsunto(s)
Cromotripsis , Mieloma Múltiple , Humanos , Mieloma Múltiple/genética , Aberraciones CromosómicasRESUMEN
Objective: To investigate the etiology of necrotizing pneumonia (NP) in children and the clinical characteristics of NP caused by different pathogens in China. Methods: A retrospective, case-control study was performed in children with NP who were admitted to 13 hospitals in China from January 2008 to December 2019. The demographic and clinical information, laboratory data, etiological and radiological findings were analyzed. The data were divided into three groups based on the following years: 2008-2011, 2012-2015 and 2016-2019, and the distribution characteristics of the pathogens in different period were compared. Meanwhile, the pathogens of pediatric NP in the southern and northern China were compared. And the clinical characteristics of the Mycoplasma pneumoniae (MP) NP and the bacterial NP were also compared. T-test or Mann-Whitney nonparametric test was used for comparison of numerical variables, and χ2 test was used for categorical variables. Results: A total of 494 children with NP were enrolled, the median ages were 4.7 (0.1-15.3) years, including 272 boys and 222 girls. Among these patients, pathogens were identified in 347 cases and the pathogen was unclear in the remaining 147 cases. The main pathogens were MP (238 cases), Streptococcus pneumoniae (SP) (61 cases), Staphylococcus aureus (SA) (51 cases), Pseudomonas aeruginosa (13 cases), Haemophilus influenzae (10 cases), adenovirus (10 cases), and influenza virus A (7 cases), respectively. MP was the most common pathogen in all three periods and the proportion increased yearly. The proportion of MP in 2016-2019 was significantly higher than that in 2012-2015 (52.1% (197/378) vs. 36.8% (32/87), χ2=6.654, P=0.010), while there was no significant difference in the proportion of MP in 2012-2015 and that in 2008-2011 (36.8% (32/87) vs. 31.0% (9/29), χ²=0.314, P=0.575).Regarding the regional distribution, 342 cases were in the southern China and 152 in the northern China. Also, MP was the most common pathogen in both regions, but the proportion of MP was higher and the proportion of SP was lower in the north than those in the south (60.5% (92/152) vs. 42.7% (146/342), χ2=13.409, P<0.010; 7.9% (12/152) vs. 14.3% (49/342), χ2=4.023, P=0.045). Comparing the clinical characteristics of different pathogens, we found that fever and cough were the common symptoms in both single MP and single bacterial groups, but chest pain was more common (17.0% (34/200) vs. 6.1% (6/98), χ2=6.697, P=0.010) while shortness of breath and wheezing were less common in MP group (16.0% (32/200) vs. 60.2% (59/98), χ2=60.688, P<0.01; 4.5% (9/200) vs. 21.4% (21/98), χ2=20.819, P<0.01, respectively). The white blood cell count, C-reactive protein and procalcitonin in the bacterial group were significantly higher than those in the MP group (14.7 (1.0-67.1)×109/L vs. 10.5 (2.5-32.2)×109/L, 122.5 (0.5-277.3) mg/L vs. 51.4 (0.5-200.0) g/L, 2.13 (0.05-100.00) µg/L vs. 0.24 (0.01-18.85) µg/L, Z=-3.719, -5.901 and -7.765, all P<0.01). Conclusions: The prevalence of pediatric NP in China shows an increasing trend during the past years. MP, SP and SA are the main pathogens of NP, and the most common clinical symptoms are fever and cough. The WBC count, C-reactive protein and procalcitonin in bacterial NP are significantly higher than those caused by MP.
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Neumonía por Mycoplasma , Neumonía Necrotizante , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , China/epidemiología , Femenino , Humanos , Lactante , Masculino , Neumonía por Mycoplasma/epidemiología , Estudios RetrospectivosRESUMEN
Small interfering RNA (siRNA) is mainly involved in RNA interference for stopping gene translation by targeting and degrading HBV-transcribed mRNA. Targeting and stability in siRNA can be enhanced via chemical modification, combination use and improved delivery system. Clinical studies have identified JNJ-3989 (ARO-HBV) and ARB-1740 as well-tolerated siRNA drugs, which significantly reduce HBsAg levels. This article expounds the main mechanisms of siRNA in inhibiting HBsAg expression, improving target and stability as well as relevant preclinical and clinical studies.
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Virus de la Hepatitis B/efectos de los fármacos , ARN Interferente Pequeño/farmacología , Replicación Viral/efectos de los fármacos , ADN Viral/análisis , Antígenos de Superficie de la Hepatitis B/análisis , Virus de la Hepatitis B/genética , Hepatitis B Crónica , Humanos , Interferencia de ARNRESUMEN
Objective: To study the value of unmethylated cytosine guanine dinucleotide oligodeoxynucleotide (DSP30) and IL-2 in the conventional cytogenetic (CA) detection of the chromosomal aberrations in chronic lymphocytic leukemia (CLL) . Methods: Bone marrow or peripheral blood cells of CLL patients were cultured with DSP30 plus IL-2 for 72 h, following which R-banding analysis was conducted. Fluorescence in situ hybridization (FISH) was performed in 85 patients. CA results were compared with data obtained by FISH. Results: Among 89 CLL patients, the success rate of chromosome analysis was 94.38% (84/89) . Clonal aberrations were detected in 51 patients (51/84, 60.71%) . Of them, 27 (27/51, 52.94%) were complex karyotype. Among 85 CLL patients tested by FISH, chromosomal abnormalities were detected in 74 (74/85, 87.06%) patients, of which 2 (2/74) patients were complex karyotypes, accounting for 2.70%. Of the 85 CLL patients examined by FISH, 50 had abnormal karyotype analysis, 30 had normal karyotype, 5 failed to have chromosome analysis. Among them, 25 cases showed clonal aberrations by FISH assay but normal by CA, and 4 cases were normal by FISH but displayed aberrations in chromosome analysis, and totally 78 (91.76%) cases with abnormality detected by the combination of the two methods. The frequency of 13q- abnormality detected by FISH was significantly higher than that by CA analysis (69.41%vs 16.67%, P<0.001) , while the frequency of 11q-,+12 and 17p- detected by two methods showed no significant difference (P>0.05) . The detection rate of complex abnormalities in conventional karyotype analysis was higher than that in FISH (50.98%vs 2.70%) . In addition, 11 low-risk and 9 intermediate-risk patients according to FISH results showed complex karyotype by cytogenetics, and were classified into high-risk cytogenetic subgroup. Conclusion: DSP30 and IL-2 are effective in improving the detection rate of CA in CLL patients (60.71%) and CA is more effective to detect complex karyotype. However, FISH had a higher overall abnormality detection rate (87.06%) than CA, especially for 13q-. The combination of CA and FISH not only enhanced the detection rate of clonal aberrations to 91.76%, but also provided more precise prognosis stratification for CLL patients, thus to provide more information for clinical implication.
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Leucemia Linfocítica Crónica de Células B , Aberraciones Cromosómicas , Citogenética , Humanos , Hibridación Fluorescente in Situ , Interleucina-2RESUMEN
Objective:To establish normative data for wideband absorbance measurements in Chinese with normal ear and effusion ear using wideband tympanometry(WBT) and determine the WBT curves of normal ears and effusion ears to facilitate the use of it. To investigate whether there are difference between the WBT absorbance in children aged 2-16 and adults above 16. To compare the sensitivity and specificity of WBT and conventional tympanometry tests for diagnosing otitis media with effusion (OME).Method:One hundred and seventy-six patients(342ears) ,from January 2015 to December 2015, were enrolled, including 96 males and 80 females whose ages ranged from 2 to 74 years. All of these patients, who underwent physical examination, ear endoscopy, conventional tympanometry and pure tone audiometry, were divided into three groups, namely normal, negative pressure and effusion according to the clinical diagnosis. WBT was carried out in these patients to analyze whether there are difference in the absorbance between children and adults in normal ears.The absorbance diagram of normal, effusion and negative pressure ears were mapped in Chinese population.The normal WBT curve was named as type N (normal) curve, the middle ear effusion curve as type E (effusion) curve, and the middle ear negative pressure curve as type P (negative pressure) curve. Pairwise comparison was carried out to analyze the difference of the WBT absorbance among these WBT curves. Other 40 patients (66 ears) with clinical diagnosis of middle ear effusion, including 22 males and 18 females with ages ranged from 3 to 36 years old, underwent exploratory tympanotomy. These 40 cases were detected preoperatively by both conventional tympanometry and WBT by which the sensitivity and specificity were compared in the diagnosis of middle ear effusion.Result:The normative data of WBT absorbance in Chinese with normal ear over 2 years old was established. The WBT absorbance at all frequencies between children and subject over 16 years old showed no statistically significant difference except for 10 frequencies in all 31 frequencies detected. The variations in the absorbance were mainly concentrated on the frequencies ranged from 500- 2000 Hz,in patients with OME. In the frequency range of 500-2000 Hz, the absorbance amplitudes in type N curv >type P curve>type E curve. There were significant differences in WBT absorbance at all frequencies between type N and type E between within 500-2000 Hz.The sensitivity and specificity of WBT for middle ear effusion were 94.8% and 87.5%, respectively, which were higher than that of conventional tympanometry with 91.3% of the sensitivity and 62.5% of the specificity.Conclusion:The WBT absorbance is consistent at most of the frequencies in Chinese. The normal ear, effusion and negative pressure in the middle ear can be distinguished by WBT curve. WBT can be useful for clinical diagnosis of OME, which has a higher sensitivity and specificity than conventional tympanometry.
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Objective: To investigate the overexpression frequencies of BRE and EVI1, the correlation between BRE and EVI1 expressions and their possible clinical implications in 11q23/MLL rearrangement acute leukemia. Methods: Cytogenetic examination of bone marrow cells was performed by short-term culture method. R-banding technique was used for karyotype analysis. 47 patients were detected by interphase fluorescence in situ hybridization (FISH) with dual-color break apart MLL probe. The expressions of EVI1 and BRE genes were detected by real time quantitative reverse transcription polymerase chain reaction (RQ-PCR) . The correlation and prognostic significance were statistically tested. Results: 11q23/MLL rearrangements were confirmed by karyotyping and FISH, respectively in 47 patients. According to immunophenotypic analyses of 37 patients, 5 patients showed positive for CD19, CD79a or CD10, 1 for CD7; the others for CD33, CD13, CD14 and CD15, and 16 of them for CD34. Of the 47 patients, 18 patients showed EVI1 overexpression and most of them presented with t (6;11) and M(4)/M(5). The EVI1 expression was high in t (6;11) or t (9;11) subgroup comparable with levels observed in normal subgroup (P=0.038, 0.022, respectively) . 15 patients showed high BRE expression, and most of them presented with t (9;11) and M(4)/M(5). High BRE expression was found in t (4;11) , t (6;11) , t (9;11) and t (11;19) subgroups, respectively by comparing with normal subgroup. The BRE expression was higher in t (4;11) (P=0.004) or t (9;11) (P=0.012) subgroup than in t (6;11) subgroup. Patients with EVI1 overexpression had a short survival compared with those with low EVI1 expression (P=0.049) and it also did in t (9;11) subgroup (P=0.024) . Patients with t (9;11) and high BRE expression had a long survival compared with those with t (9;11) and low BRE expression (P=0.024) . Conclusion: The EVI1 overexpression was significantly frequent in acute leukemia patients with 11q23/MLL rearranged, especially within t (6;11) subgroup and M(4)/M(5), which was associated with an inferior outcome. High BRE expression was observed frequently in 11q23/MLL-rearranged acute leukemia especially within t (9;11) subgroup and M(5).
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Cromosomas Humanos Par 11 , Leucemia Mieloide Aguda , Enfermedad Aguda , Células de la Médula Ósea , Bandeo Cromosómico , Reordenamiento Génico , N-Metiltransferasa de Histona-Lisina , Humanos , Inmunofenotipificación , Hibridación Fluorescente in Situ , Interfase , Cariotipificación , Proteína de la Leucemia Mieloide-Linfoide , Pronóstico , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
AIM: This study aimed to understand the role of miR-133a in progesterone actions, explore the regulative mechanism of the progesterone receptor, and investigate the effects of miR-133a on the progesterone-inhibited proliferation of mouse endometrial epithelial cells. METHODS: The expression of miR-133a induced by progesterone was detected by quantitative real-time PCR both in vivo and in vitro. Ishikawa subcell lines stably transfected with progesterone receptor subtypes were used to determine the receptor mechanism of progesterone inducing miR-133a. Specific miR-133a mimics or inhibitors were transfected into mouse uteri and primary cultured endometrial epithelial cells to overexpress or downregulate the miR-133a. The roles of miR-133a in the cell cycle and proliferation of endometrial epithelial cells were analysed by flow cytometry and Edu incorporation analysis. The protein levels of cyclinD2 in uterine tissue sections and primary cultured endometrial epithelial cells were determined by immunohistochemistry and Western blot analysis. RESULTS: Progesterone could induce miR-133a expression in a PRB-dependent manner in endometrial epithelial cells. miR-133a inhibited endometrial epithelial cell proliferation by arresting cell cycle at the G1 -S transition. Moreover, miR-133a acted as an inhibitor in downregulating cyclinD2 in endometrial epithelial cells. CONCLUSION: We showed for the first time that progesterone-induced miR-133a inhibited the proliferation of endometrial epithelial cells by downregulating cyclinD2. Our research indicated an important mechanism for progesterone inhibiting the proliferation of endometrial epithelial cells by inducing special miRNAs to inhibit positive regulatory proteins in the cell cycle.
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Ciclina D2/biosíntesis , Endometrio/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , MicroARNs/metabolismo , Progesterona/farmacología , Animales , Western Blotting , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Células Epiteliales/metabolismo , Femenino , Citometría de Flujo , Inmunohistoquímica , Ratones , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Objective: To retrospectively analyze the clinical features, cytogenetic characteristics and survival of 550 newly diagnosed myelodysplastic syndrome(MDS)patients. Method: By using WHO(2008)criterion for classification, the prognosis of stratification of 550 patients were evaluated according to the IPSS/WPSS/IPSS-R. Results: The median age was 57 years old(range: 12-89 years old). The ratio of male and female was 1.72. In all patients, the median hemoglobin level was 72(22-154)g/L, the median platelet count was 52(3-587)×109/L and the median WBC was 2.52(0.11-48.00)×109/L. 45.6%(251/550)patients had clonal chromosome abnormalities, in which 89(16.2%)patients with complex karyotype. The types of chromosome aberration were mainly dominated by unbalanced anomalies, and the most common types of chromosome aberration were trisomy or monosomy. The most common abnormity was +8. Other aberrations in frequent order were - 7/del(7q), del(5q), del(20q), and so on. In addition, 550 patients were evaluated according to IPSS, IPSS-R, and WPSS prognostic scoring system. The results showed that the IPSS, WPSS and IPSS-R scores were significantly affected OS(P <0.001). The median OS in the IPSSR Low, Intermediate, High and Very Highrisk groups was not reached, 44(95%CI 28-60), 17(95%CI 13- 21)and 8(95%CI 5-11)months, respectively. Conclusion: In this study, the patients' median age was 57(12- 89)years old, and the cytogenetic characteristics were significantly different from western MDS patients. IPSS, IPSS-R and WPSS were important in predicting the survival of MDS patients.
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Síndromes Mielodisplásicos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Aberraciones Cromosómicas , Citogenética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monosomía , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia , Trisomía , Adulto JovenRESUMEN
Complex chromosomal aberrations (CCA) can be detected in a substantial proportion of myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML), which are associated with very poor prognosis. Conventional cytogenetics (CC) cannot accurately define the specific alterations in CCA. Multiplex fluorescence in situ hybridization (M-FISH) allows the comprehensive identification of CCA. In this study, M-FISH was used in 16 patients with de novo MDS and 22 with AML with CCA detected by R-banding CC, and revealed 206 aberrations involved all 24 chromosomes, including 73 numerical chromosomal abnormalities and 133 structural abnormalities. The chromosomes most often involved were, by decreasing incidence, 5, 17, 8, 11, 7 and 21 in 57.9%, 55.3%, 44.7%, 36.8%, 34.2% and 34.2% of the cases, respectively. There were 98 unbalanced translocations, which were the most frequently observed aberrations in our study. Derivative chromosome 5 and 8 were implicated most often. The other derivatives were der(11), der(12), der(7), der(14), der(15) and der(17). Fourteen balanced translocations were detected in our series, and the most frequent reciprocal translocations was t(8;21). Fifty-five monosomies, 15 partial deletions, and 18 trisomies were found in all patients. The most frequently observed were -5/5q-, -17/17q-, -7, -18, -21, -19, and trisomy of chromosome 8 and 6. There were some abnormalities that have not been previously described, including two complex t(8;21) and seven unbalanced translocations. M-FISH could refine CCA, find or correct the missed or misidentified aberrations by CC analysis. Our findings confirmed that M-FISH was a powerful molecular cytogenetic tool to characterize complex karyotypes in MDS and AML.
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Cromosomas Humanos/genética , Hibridación Fluorescente in Situ/métodos , Cariotipificación/métodos , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicos/genética , Adolescente , Adulto , Anciano , Niño , Cromosomas Humanos Par 5/genética , Cromosomas Humanos Par 8/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Translocación Genética , TrisomíaRESUMEN
BACKGROUND: Myelodysplastic syndrome (MDS) constitutes a heterogeneous group of hematopoietic stem cell disorder characterized by peripheral blood cytopenia(s), in the presence of hypercellular bone marrow with features of ineffective hematopoiesis, and susceptibility to acute leukemia (AL). Although the precise pathogenesis of MDS remains to be clarified, cytogenetic abnormalities seem to be involved in its pathogenesis and are considered as an important factor in diagnosis and predicting clinical outcome. OBJECTIVE: To explore the cytogenetic features of Chinese patients with myelodysplastic syndrome (MDS). METHODS: Conventional cytogenetic analysis was performed in 88 MDS patients and among them, 34 cases were studied by interphase fluorescence in situ hybridization (I-FISH) with precisely chromosome 8 centromere specific DNA probe and DNA specific probes for 7q32 , 5q31. RESULTS: Of the 88 patients, 45 (51.1%) showed clonal karyotypic abnormalities by CC at diagnosis, including numerical changes (18 cases, 20.5%), structural changes (12 cases, 13.6%), and numerical and structural changes simultaneously(15 cases, 17.0%). Trisomy 8, -5/5q-, and -7/ 7q- account for 20.5%, 15.9%, and 5.7% respectively. Complex karyotypes were observed in 17 patients, the incidence being 19.3% in the whole series of cases. Among 34 MDS patients studied by I-FISH, -5/5q-, -7/7q- and trisomy 8 occurring in 4, 2 and 10 cases respectively for CC were confirmed by I-FISH. 5 cases in 30 cases who did not show -5/5q- by CC displayed this abnormality by I-FISH. 3 cases without -7/7q- by CC presented this aberration by I-FISH. 5 cases with trisomy 8 for I-FISH was not identified this change by CC. CONCLUSIONS: The frequent abnormalities are trisomy 8, -5/5q- and -7/ 7q-. FISH is very useful in detecting these alterations in MDS and it is an important complement to CC.
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Cromosomas Humanos Par 5/genética , Cromosomas Humanos Par 7/genética , Cromosomas Humanos Par 8/genética , Análisis Citogenético , Síndromes Mielodisplásicos/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , China , Aberraciones Cromosómicas , Bandeo Cromosómico , Femenino , Humanos , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana EdadRESUMEN
Some previous works showed that radiative transfer between two closely spaced, lossy media diverges as 1/L(2), where L is the spacing between the two media. This divergent power transfer clearly violates energy conservation. The explanation for this unphysical result is that too many optical modes were counted in those previous works, and many of those modes are physically unattainable. Moreover, many physically significant optical modes were not counted in the previous works.
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Published works have predicted that the radiative transfer from a heated metal to a lossless dielectric a short distance away is many orders of magnitude times the free-space Planck density. It is shown analytically that the radiative transfer from a heated metal to a lossless dielectric of index n(3) is n(3)(2)e(13) times the free-space Planck density, where e(13) is the emissivity of the metal radiating into the lossless dielectric. This radiative transfer is never larger than n(3)(2) (approximately one order of magnitude for semiconductors in the infrared) times the free=space Planck density. The expressions presented show that the maximum radiative transfer from a lossy metallic heat source with a dielectric function of imaginary part ?(I) must be proportional to n(3)(3)/ radical?(I), of which a factor of n(3)(2) arises from the power density within a dielectric and a factor of n(3)/ radical?(I) arises from the emissivity of a metal radiating directly into a dielectric.
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AIM: To study the efficacy of huperzine-A capsules (Hup) on memory and learning performance of adolescent students. METHODS: Using double-blind and matched pair method, 34 pairs of junior middle school students complaining of memory inadequacy were divided into two groups by normal psychological health inventory (PHI), similar memory quotient (MQ), same sex and class. The Hup group was administrated orally 2 capsules of Hup (each contains Hup 50 micrograms) b.i.d., and the placebo group was given 2 capsules of placebo (starch and lactose inside) b.i.d. for 4 wk. RESULTS: At the end of trial, the Hup group's MQ (115 +/- 6) was more than that of the placebo group (104 +/- 9, P < 0.01), and the scores of Chinese language lesson in the Hup group were elevated markedly too. CONCLUSION: The Hup capsules enhance the memory and learning performance of adolescent students.
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Inhibidores de la Colinesterasa/farmacología , Aprendizaje/efectos de los fármacos , Memoria/efectos de los fármacos , Sesquiterpenos/farmacología , Adolescente , Adulto , Alcaloides , Cápsulas , Método Doble Ciego , Femenino , Humanos , Masculino , Análisis por Apareamiento , Escalas de WechslerRESUMEN
A series of epipodophyllotoxin carboxylates were prepared from podophyllotoxin by reacting with organic acids under the catalysis of BF3.Et2O. All these products were characterized through IR, 1HNMR, MS and elemental analysis. These compounds showed significant antitumor activities against mouse leukemia P388 and human stomach cancer SGC-7901 in pharmacological tests in vitro.
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Antineoplásicos Fitogénicos/síntesis química , Podofilotoxina/química , Adenocarcinoma/patología , Animales , Antineoplásicos Fitogénicos/farmacología , Carcinoma Hepatocelular/patología , Humanos , Leucemia P388/patología , Neoplasias Hepáticas/patología , Ratones , Estructura Molecular , Neoplasias Gástricas/patología , Células Tumorales Cultivadas/efectos de los fármacosRESUMEN
To determine the prognostic importance of pulsed Doppler-derived left ventricular diastolic filling velocity profiles and the relationship between Doppler variables and clinical functional status, the follow-up outcome of 58 patients with dilated cardiomyopathy and symptoms of left ventricular dysfunction was analysed. During a mean follow-up period of 31.2 +/- 12.8 months, 23 died of either progressive pump failure or sudden death. Peak early filling velocity (E) was higher and late atrial filling velocity (A) lower in nonsurvivors than in survivors. The E/A ratio was higher and the deceleration time (DT) of early diastole shorter in nonsurvivors. The mortality was significantly higher in patients with an E/A ratio > 2 or a DT < 150 ms than in those without. Repeated Doppler echocardiographic examinations in 31 of 35 survivors after intense treatment showed decreased E, increased A, reduced E/A ratio and prolonged DT in 18 patients with clinical functional improvement, whereas these measurements were unaltered in the remaining 13 patients whose functional status was unchanged or deteriorated. This study suggests that pulsed Doppler-derived left ventricular diastolic filling variables may be important predictors of outcome in dilated cardiomyopathy and provide useful measures in observing the effects of therapy during long-term follow-up of the patients.