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1.
Zhonghua Liu Xing Bing Xue Za Zhi ; 39(12): 1576-1581, 2018 Dec 10.
Article in Chinese | MEDLINE | ID: mdl-30572381

ABSTRACT

Objective: To evaluate the randomness and representativeness of respondent- driven sampling (RDS) tool in conducting the investigation in MSM population, in Beijing, 2017. Methods: RDS tool was used to recruit MSM population for a face-to-face interview with structured questionnaire and serological tests. Results: A total of 600 MSM people were sampled and interviewed. The median number of personal network of seeds was 10, which was higher than other MSM people recruited. The numbers of recruitments by wave presented a skewed positive distribution and the highest number was in the fourth wave. It was also dramatically varied from different seeds. Three seeds had the longest chains and had recruited 184, 113 and 92 MSM people, respectively. In contrast, five seeds recruited less than 10 MSM people. Two college students were the most non-generative seeds and each recruited only 1 MSM person. After five to nine waves of sampling, the major demographic characteristics reached equilibrium. Both convergence and bottleneck plots of major demographic characteristics reached convergence, although the plots on marriage and education did not. The homophiles of characteristics were all closed to 1, except for education. The HIV positive rate appeared as 7.9% (95%CI: 4.4%-11.4%) . Conclusions: Results from this study showed that RDS could be used as a feasible sampling method for the study on MSM population with major demographic characteristics reached equilibrium. The process of recruitment appeared controllable and reasonable, showing that this could represent the MSM population in Beijing, in some degree.


Subject(s)
HIV Infections/epidemiology , Homosexuality, Male/statistics & numerical data , Patient Selection , Sexual and Gender Minorities , Surveys and Questionnaires , Beijing/epidemiology , Humans , Male , Outcome Assessment, Health Care/methods , Outcome Assessment, Health Care/statistics & numerical data , Prevalence , Sampling Studies
2.
Article in Chinese | MEDLINE | ID: mdl-29771092

ABSTRACT

Primary thyroid paraganglioma (PTPG) is rare,we report a case of 55 years old women with PTPG, which describes the clinical features, diagnosis and treatment. A possible diagnosis, treatment and follow-up strategy was proposed by reviewing relevant reports. It aims to improve the cognitive of PTPG and standardize its treatment.


Subject(s)
Paraganglioma , Thyroid Neoplasms , Female , Humans , Immunohistochemistry , Middle Aged , Paraganglioma/diagnostic imaging , Paraganglioma/therapy , Thyroid Neoplasms/diagnostic imaging , Thyroid Neoplasms/therapy
3.
Eur Rev Med Pharmacol Sci ; 21(16): 3605-3610, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28925483

ABSTRACT

OBJECTIVE: Down-regulation of long non-coding RNA tumor suppressor candidate 7(TUSC7) contributes to tumorigenesis in several human cancers including glioma. However, the prognostic value of TUSC7 in glioma remains unclear. The present study aimed to investigate the clinicopathological and prognostic value of TUSC7. PATIENTS AND METHODS: The expression level of TUSC7 in glioma tissues and matched normal tissues were detected by qRT-PCR. Then, the association of serum TUSC7 expression level with various important clinicopathological parameters and survival rates was evaluated. The Cox regression analysis was used to evaluate the effect of independent prognostic factors on survival outcome. RESULTS: The relative level of TUSC7 was significantly lower in glioma tissues compared to the adjacent normal brain tissues (p < 0.01). In addition, a lower expression of TUSC7 was observed in high-grade glioma tissues than in low-grade glioma tissues (p < 0.01). Furthermore, the low expression of TUSC7 was associated with poor clinicopathological characteristics of glioma, including WHO grade (p = 0.002) and KPS (p = 0.026). Then, the low TUSC7 level was correlated with shorter disease free survival (DFS) and overall survival (OS) than low level (both p = 0.05). Finally, univariate and multivariate Cox analysis showed that TUSC7 was an independent prognostic indicator for OS and DFS. CONCLUSIONS: These results provided evidence that TUSC7 may be a potential biomarker in the prognosis of glioma.


Subject(s)
Brain Neoplasms/mortality , Glioma/mortality , RNA, Long Noncoding/physiology , Adult , Aged , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Disease-Free Survival , Female , Glioma/genetics , Glioma/pathology , Humans , Male , Middle Aged , Proportional Hazards Models , RNA, Long Noncoding/analysis
4.
Andrologia ; 49(3)2017 Apr.
Article in English | MEDLINE | ID: mdl-27421248

ABSTRACT

Mean platelet volume (MPV) and Platelet distribution width (PDW) are potential markers in platelet activation. In present study, we aimed to evaluate MPV and PDW as potential severity markers for those patients who are complaining erectile dysfunction (ED). A total of 358 participants were enrolled in this study. The whole cohort was asked to complete the International Index of Erectile Function-5 (IIEF-5) questionnaire. The participants were classified into 3 groups: control group (n = 120), mild ED (n = 118) and severe ED (n = 120). We found in our cohort MPV and PDW were significantly higher in both mild ED group and severe ED group than control group (9.24 ± 0.70 and 9.71 ± 0.80 versus 8.56 ± 0.62 for MPV; 14.48 ± 1.29 and 14.98 ± 1.60 versus 12.86 ± 1.13 for PDW respectively). The MPV and PDW increased as the disease progressed. In the mild and severe ED groups, a significant inverse correlation was detected between the mean values of IIEF-5 score and PDW. Furthermore, in the receiver operating characteristic curve analysis, the area under the curve of the MPV and PDW to predict severe ED was 0.818 and 0.848 respectively. Our study establishes a dose-dependent association between the PDW and ED. Therefore, the PDW can serve as a potential marker for predicting the severity of ED.


Subject(s)
Blood Platelets/physiology , Erectile Dysfunction/blood , Mean Platelet Volume , Adult , Cohort Studies , Humans , Male , ROC Curve , Risk Factors , Severity of Illness Index , Surveys and Questionnaires
5.
Zhonghua Liu Xing Bing Xue Za Zhi ; 37(10): 1383-1391, 2016 Oct 10.
Article in Chinese | MEDLINE | ID: mdl-27765131

ABSTRACT

Objective: To understand the HIV prevalence among men who have sex with men (MSM) and discuss the feasibility of respondent driven sampling (RDS) as a tool to conduct long term HIV surveillance in MSM in Beijing. Methods: From 2005 to 2012 RDS was used to recruit MSM for face-to-face interview with structured questionnaire to collect their demographic characteristics and HIV risk-related behavior. Blood samples were collected from them for HIV test. Results: A total of 427, 540, 607, 614, 616, 602, 579 and 600 MSM were surveyed, respectively, from 2005 to 2012. The HIV infection prevalence increased from 4.2%(95%CI: 1.9-7.0) in 2005 to 10.1% (95%CI: 7.2-13.2) in 2012 (P=0.02). Meanwhile, HIV prevalence substantially increased among MSM aged >25 years, in floating population and with lower education level (≤high school), from 6.4%(95%CI: 2.2-9.5), 3.3%(95%CI: 1.8-5.4) and 5.5% (95%CI: 2.2-8.9) in 2005 to 7.6% (95%CI: 5.4-10.3, P=0.04), 10.7% (95% CI: 7.8-14.6, P=0.04) and 10.4% (95% CI:7.2-14.3, P=0.04) in 2012, respectively. Moreover, the HIV infection prevalence in MSM aged ≤25 years old and with higher education level (>high school) increased from 1.7%(95%CI: 0.4-3.1) in 2009 and 1.1%(95%CI: 0.2-1.7) in 2007 to 13.7%(95%CI: 7.2-20.4) and 9.1%(95%CI: 4.7-13.8) in 2012, respectively, the differences were not significant. Furthermore, the HIV infection prevalence in MSM who had 2-9 male sex partners in the last six months increased from 4.0% (95% CI: 1.0-8.0) in 2005 to 12.6% (95% CI: 8.7-16.7) in 2012 (P=0.02). Conclusions: Studies have shown that RDS is an effective and feasible sampling method for long term HIV surveillance in MSM. The HIV infection prevalence in MSM in Beijing increased from 2005 to 2012, especially among those with older age, in floating population and with lower educational level. More attention should be paid to MSM with younger age and with higher educational level.


Subject(s)
HIV Infections , Homosexuality, Male , Adult , Beijing , Humans , Male , Mass Screening , Prevalence , Risk Factors , Sexual Behavior , Sexual Partners , Specimen Handling , Surveys and Questionnaires
6.
Zhonghua Yi Xue Za Zhi ; 96(22): 1746-9, 2016 Jun 14.
Article in Chinese | MEDLINE | ID: mdl-27356641

ABSTRACT

OBJECTIVE: To investigate the clinical significance of the three-step approach in laparoscopic hemihepatectomy. METHODS: A total of 32 patients received laparoscopic hemihepatectomy with the three-step approach in Yijishan Hospital affiliated to Wannan Medical College between Aug 2013 and Oct 2015. All patients underwent thin slice CT scan and hemihepatectomy was imitated with the imagic explorer, preoperatively. The vessel distribution was observed at the section and the three-step approach was used in the hemihepatectomy. Pre- and post-operative data were collected and analyzed retrospectively. RESULTS: The length of middle hepatic vein (MHV) was (59.1±12.9) mm and the number of branchs to the left and right lobe were 3.07±0.78 and 3.11±0.64 respectively. The distance between the first branch of MHV and the diaphragmatic surface was (28.07±3.74) mm and the distance between MHV and the visceral surface was (14.4±4.3) mm. The laparoscopic surgeries (left hemihepatectomy in 28 and right hemihepatectomy in 4) were performed successfully in all cases with the three-step approach, without any conversion to the open surgeries. The operation time was (165±42) min in left hemihepatectomy and (305±50) min in right hemihepatectomy. The intraoperative blood loss was (242±65) ml in left hemihepatectomy and (695±122)ml in right hemihepatectomy. All the patients recovered well without severe complications except for bile leakage in 3 patients who were cured with drainage. The postoperative hospital stay was (7.96±1.8) d. CONCLUSIONS: the distribution of vessel is regional at the section of hemihepatectomy and the three-step approach based on this feature is safe and effective in laparoscopic hemihepatectomy, which can shorten the operation time and reduce the difficulty of operation.


Subject(s)
Hepatectomy/methods , Hepatic Veins/diagnostic imaging , Laparoscopy/methods , Liver/surgery , Blood Loss, Surgical , Hepatectomy/instrumentation , Humans , Laparoscopy/instrumentation , Length of Stay , Liver/diagnostic imaging , Retrospective Studies , Treatment Outcome
7.
Res Vet Sci ; 103: 143-8, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26679809

ABSTRACT

Breast cancer 1, early onset (BRCA1) is one of the most important genes in human familial breast cancer, which also plays an important role in canine mammary tumors. The objectives of this study were to determine the promoter sequence of canine BRCA1, to investigate its promoter mutation status and to describe BRCA1 expression pattern in canine mammary tumors. The promoter sequence of canine BRCA1 was acquired by aligning human BRCA1 promoter sequence with canine genomic sequence and confirmed by standard promoter activity analysis. Same as human BRCA1 promoter, the CAAT box and G/C box were found in canine BRCA1 promoter. In order to explore the mutation status of the promoter region and to investigate the expression pattern of this gene, 10 normal canine mammary tissues, 15 benign mammary tumors and 15 malignant mammary tumors were used. By sequencing, 46.7% of the malignant mammary tumors were found with a deletion of one cytosine in the promoter region. The mRNA expression of BRCA1 was significantly reduced in benign and malignant mammary tumors (P<0.05), and the protein expression of BRCA1 was significantly reduced in malignant mammary tumors (P<0.05). This study is the first time to determine the canine BRCA1 promoter sequence and to describe the promoter mutation status in canine mammary tumors.


Subject(s)
BRCA1 Protein/genetics , Dog Diseases/genetics , Mammary Neoplasms, Animal/genetics , Mutation , Promoter Regions, Genetic , Animals , BRCA1 Protein/metabolism , Base Sequence , Dogs , Female , Sequence Alignment/veterinary
8.
Clin Radiol ; 68(6): 568-73, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23347469

ABSTRACT

AIM: To evaluate the reliability and utility of preoperative perforator planning using computed tomography angiography (CTA) in anterolateral thigh perforator flap (ALTPF) transplantation. MATERIALS AND METHODS: Thirty-two consecutive patients who underwent extremity reconstruction using the ALTPF were retrospectively reviewed from 2008 to 2012. These patients were divided into two groups. In group I (n = 16), suitable perforators were designed based on four criteria using CTA. These were used for the operation and compared with the intraoperative findings. In group II (n = 16), all patients underwent operation using conventional methods without preoperative perforator planning. The surgical results of all patients were evaluated for flap complications, alteration of the donor site, donor site morbidity, and the incidence of reoperation. RESULTS: In group I, there were no statistically significant differences between the parameters, including the calibre and location of the origin (perpendicular and horizontal distance from the origin of the perforator to both the superior lateral border of the patella and the lateral region of the thigh) of all planning perforators and the operative measurement results (p-values were 0.3, 0.422, and 0.129, respectively). The types were consistent with the operative findings; the rate of the septocutaneous type was 31.25% (5/16), and the rate of the musculocutaneous type was 68.75% (11/16). The use of preoperative perforator planning in group I was associated with a significant reduction in flap complications (p = 0.009) compared with group II. There was no difference between the two groups in alteration of the donor site, donor site morbidity, or the incidence of reoperation (p-values were 0.225, 0.225, and 0.33, respectively). CONCLUSION: Preoperative perforator planning using CTA in ALTPF transplantation is a reliable and useful method resulting in safer operation with optimal outcome.


Subject(s)
Angiography/methods , Perforator Flap/transplantation , Thigh/surgery , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Perforator Flap/blood supply , Preoperative Care/methods , Plastic Surgery Procedures/methods , Retrospective Studies , Thigh/blood supply , Tomography, X-Ray Computed/methods , Treatment Outcome , Young Adult
9.
Br Poult Sci ; 47(2): 230-6, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16641035

ABSTRACT

The present study was conducted to examine the effect of supplemental L-arginine on pulmonary arteriole protein kinase Calpha (PKCalpha) expression in broilers exposed to cool temperature, to investigate further the molecular mechanisms of supplemental L-arginine on modulating pulmonary vascular functions in hypertensive broilers. Broilers were subjected to sub-thermoneutral (cool) temperature to induce pulmonary hypertension syndrome (PHS), and an additional 10 g/kg L-arginine was added to the basal diet to evaluate the effects of supplemental L-arginine on PHS mortality, plasma nitric oxide (NO) production and pulmonary arterioles PKCalpha expression. Supplemental L-arginine reduced PHS mortality but did not affect right/total ventricle (RV/TV) ratios in clinically healthy birds. Birds fed additional L-arginine had increased plasma NO and decreased PKCalpha protein expression in pulmonary arterioles; NO production was negatively correlated with PKCalpha expression. These results demonstrated that supplemental L-arginine diminished PKCalpha expression in birds exposed to cool temperature. It is suggested that NO-induced loss of PKCalpha expression might be partially responsible for its effects on dilating pulmonary vasculature and inhibiting pulmonary vascular remodelling in vivo.


Subject(s)
Arginine/administration & dosage , Chickens , Hypertension, Pulmonary/veterinary , Poultry Diseases/enzymology , Protein Kinase C-alpha/metabolism , Pulmonary Artery/enzymology , Animals , Arginine/pharmacology , Cold Temperature , Dietary Supplements , Female , Gene Expression Regulation, Enzymologic , Hypertension, Pulmonary/enzymology , Hypertension, Pulmonary/mortality , Male , Nitric Oxide/biosynthesis , Nitric Oxide/blood , Poultry Diseases/mortality , Protein Kinase C-alpha/genetics
10.
Br Poult Sci ; 46(3): 374-81, 2005 Jun.
Article in English | MEDLINE | ID: mdl-16050193

ABSTRACT

Two experiments were conducted to evaluate the effects of early feed restriction on lipid peroxidation, pulmonary vascular remodelling and ascites incidence in broilers under normal and low ambient temperature. In experiment 1, the restricted birds were fed 8h per day either from 7 to 14 d or from 7 to 21 d, while the controlled birds were fed ad libitum. In experiment 2, the restricted birds were fed 80 or 60% of the previous 24-h feed consumption of full-fed controls for 7 d from 7 to 14 d. On d 14, half of the birds in each treatment both in experiment 1 and experiment 2 were exposed to low ambient temperature to induce ascites. Body weight and feed conversion ratio were measured weekly. The incidences of ascites and other disease were recorded to determine ascites morbidity and total mortality. Blood samples were taken on d 14, 21, 28, 35 and 42 to measure the plasma malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). On d 42, samples were taken to determine the right/total ventricular weight ratio (RV/TV), vessel wall area/vessel total area ratio (WA/TA) and mean media thickness in pulmonary arterioles (mMTPA). Low-temperature treatment increased plasma MDA concentration. When broilers were exposed to a cool environment for 3 weeks, plasma SOD and GSH-Px activity were decreased compared with normal-temperature chicks. RV/TV, WA/TA and mMTPA on d 42 were increased in birds exposed to cold, consistent with the increased pulmonary hypertension and ascites morbidity. Early feed restriction markedly decreased plasma MDA concentration. The plasma SOD and GSH-Px activity of feed-restricted birds were markedly higher than those fed ad libitum on d 35 and d 42. All early feed restriction treatments reduced ascites morbidity and total mortality. On d 42, the RV/TV, WA/TA and mMTPA of feed-restricted broilers were lower than that of the ad libitum-fed broilers. The results suggested that early feed restriction alleviated the lipid peroxidation, promoted the activity of enzymatic antioxidant and inhibited pulmonary vascular remodelling. These changes might be associated with reduced ascites incidence.


Subject(s)
Chickens/physiology , Cold Temperature , Food Deprivation , Lipid Peroxidation , Lung/blood supply , Animals , Ascites/mortality , Ascites/veterinary , Glutathione Peroxidase/blood , Hypertension, Pulmonary/mortality , Hypertension, Pulmonary/veterinary , Malondialdehyde/blood , Poultry Diseases/mortality , Superoxide Dismutase/blood , Time Factors , Weight Gain
11.
Poult Sci ; 83(5): 732-6, 2004 May.
Article in English | MEDLINE | ID: mdl-15141829

ABSTRACT

Two hundred forty 1-d-old Arbor Acres commercial broiler chicks were divided into control and experimental (T1 and T2) groups that, between 8 and 42 d of age, were provided drinking water containing 0, 600, or 1,200 mg/L sodium from sodium chloride, respectively. The pulmonary hypertension syndrome (PHS) incidence and the right to total ventricle weight ratio (RV/ TV) were calculated weekly, and blood samples and lung tissues were collected weekly from 10 birds per group to evaluate the structural and hemodynamic characteristics of pulmonary vessels. Saline drinking water significantly increased the incidence of PHS and RV/TV ratios. In the T2 group the PHS mortality exhibited 2 peaks, including an acute peak from 14 to 21 d of age and a chronic peak from 35 to 42 d of age. During the acute peak of PHS mortality the blood volume (BV), filtration index (FI), and packed cell volume (PCV) increased in groups T1 and T2 when compared with the control group. During the acute peak there were no differences among groups in the ratio of wall to total area (WA/TA), medial thickness of pulmonary arteriole walls (mMTPA), the percentage of thick-walled peripheral lung vessels (%TWPV), the percentage of muscular arterioles (%MA), or the percentage of nonmuscular arterioles (%NMA) in pulmonary arterioles. During the chronic peak of PHS mortality, group T2 exhibited the highest values for %TWPV, %MA, WA/TA, and mMTPA and the lowest values for %NMA when compared with the T1 and control groups. Also during the chronic peak the groups did not differ in BV or FI, whereas PCV remained elevated above control values in groups T1 and T2. These observations indicate that hemodynamic changes related to viscous resistance to blood flow (BV, FI, PCV) predominated throughout the acute peak of PHS mortality, whereas, during the chronic stages of PHS mortality, increased vascular resistance to blood flow also was imposed by remodeling of the pulmonary vasculature.


Subject(s)
Chickens , Hypertension, Pulmonary/veterinary , Poultry Diseases/chemically induced , Sodium Chloride/adverse effects , Aging , Animals , Arterioles/pathology , Drinking , Hemodynamics , Hypertension, Pulmonary/chemically induced , Hypertension, Pulmonary/pathology , Lung/blood supply , Poultry Diseases/pathology , Sodium Chloride/administration & dosage
12.
Bioinformatics ; 20(5): 629-35, 2004 Mar 22.
Article in English | MEDLINE | ID: mdl-15033869

ABSTRACT

MOTIVATION: In silico genome analysis of bacteriophage genomes focuses mainly on gene discovery and functional assignment. The search for regulatory elements contained within these genome sequences is often based on prior knowledge of other genomic elements or on learning algorithms of experimentally determined data, potentially leading to a biased prediction output. The PHage In silico Regulatory Elements (PHIRE) program is a standalone program in Visual Basic. It performs an algorithmic string-based search on bacteriophage genome sequences to uncover and extract subsequence alignments hinting at regulatory elements contained within these genomes, in a deterministic manner without any prior experimental or predictive knowledge. RESULTS: The PHIRE program was tested on known phage genomes with experimentally verified regulatory elements. PHIRE was able to extract phage regulatory sequences correctly for bacteriophages T7, T3, YeO3-12 and lambda, based solely on the genome sequence. For 11 bacteriophages, new predictions of conserved phage-specific putative regulatory elements were made, further corroborating this approach. AVAILABILITY: http://www.agr.kuleuven.ac.be/logt/PHIRE.htm. Freely available for academic use. Commercial users should contact the corresponding author.


Subject(s)
Bacteriophages/genetics , Gene Expression Profiling/methods , Genes, Regulator/genetics , Genome, Viral , Sequence Alignment/methods , Sequence Analysis, DNA/methods , Software , Base Sequence , Gene Expression Regulation, Viral/genetics , Molecular Sequence Data , Sequence Homology, Nucleic Acid
13.
Br Poult Sci ; 43(5 Suppl): 705-12, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12555895

ABSTRACT

1. Three hundred and eighty 1-day-old Arbor Acres broilers were divided into control (A) and experimental (B, C, D, and E) groups. 2. After 14 d of age the experimental groups were subjected to a cool temperature challenge by lowering the temperature 1 to 2 degrees C per day down to 12 degrees C, and maintaining this temperature until 7 weeks of age. 3. At the same time, 1.5 mg/kg 3,3,5-triiodothyronine (T3) was added to the diet of groups D and E, and 500 mg/kg ascorbic acid (vitamin C) to the diet of groups C and E. 4. The incidence of pulmonary hypertension syndrome (PHS), body weight gain and feed intake were measured weekly. Lung and blood samples were collected weekly from 10 birds per group beginning on d 14, and the percentage of thick-walled peripheral lung vessels (% TWPV) and packed cell volume (PCV) were determined. 5. The lower ambient temperature and diets supplemented with T3 increased PHS incidence and % TWPV and decreased body weight gain. 6. There was an increase in PCV after 5 weeks of age under lower ambient temperature 3 and the PCV values 14 were also significantly increased by T3. 7. Vitamin C supplementation reduced PHS incidence and % TWPV but did not change packed cell volume, body, weight gain, feed intake, or feed conversion. 8. It is concluded that vitamin C reduced PHS and the associated muscularisation of pulmonary arterioles induced by exposing broilers to cool environmental temperatures and feeding them with T3.


Subject(s)
Ascorbic Acid/pharmacology , Chickens , Hypertension, Pulmonary/veterinary , Poultry Diseases/prevention & control , Animals , Arterioles/drug effects , Cold Temperature/adverse effects , Dietary Supplements , Hematocrit , Histocytochemistry/veterinary , Hypertension, Pulmonary/prevention & control , Lung/blood supply , Poultry Diseases/drug therapy , Poultry Diseases/metabolism , Random Allocation , Triiodothyronine/pharmacology
14.
Article in English | MEDLINE | ID: mdl-18252343

ABSTRACT

This paper presents a self-creating neural network in which a conservation principle is incorporated with the competitive learning algorithm to harmonize equi-probable and equi-distortion criteria. Each node is associated with a measure of vitality which is updated after each input presentation. The total amount of vitality in the network at any time is 1, hence the name conservation. Competitive learning based on a vitality conservation principle is near-optimum, in the sense that problem of trapping in a local minimum is alleviated by adding perturbations to the learning rate during node generation processes. Combined with a procedure that redistributes the learning rate variables after generation and removal of nodes, the competitive conservation strategy provides a novel approach to the problem of harmonizing equi-error and equi-probable criteria. The training process is smooth and incremental, it not only achieves the biologically plausible learning property, but also facilitates systematic derivations for training parameters. Comparison studies on learning vector quantization involving stationary and nonstationary, structured and nonstructured inputs demonstrate that the proposed network outperforms other competitive networks in terms of quantization error, learning speed, and codeword search efficiency.

15.
Biochem Biophys Res Commun ; 175(1): 244-9, 1991 Feb 28.
Article in English | MEDLINE | ID: mdl-1998509

ABSTRACT

Clones possessing inserts of brain myosin II have been obtained by screening a rat brain cDNA expression library with a polyclonal antibody, raised against myosin II from the mouse neuroblastoma cell line, Neuro-2A. A partial sequence comprising the 3' coding and non-coding regions of the myosin message has been determined which is markedly different from other myosin sequences. The derived amino-acid sequence comprises the C-terminal 90 amino acids: VSS(PO4)LKNKLRRGDLPFVVTRRLVRKGTLELS(PO4)DDDDESKASLINETQPPQCLDQQ LDQQ LDQLFNWPVNAGCVCGWGVEQTQGEEAVHKCRT(CO2H). This sequence encompasses regions homologous to both the casein kinase II and protein kinase C heavy-chain phosphorylation sites. The non-helical "tail-piece" is considerably longer (an additional 39 amino acid residues) than found in other myosins. Northern blot analysis demonstrates this myosin II message to be unique to cerebral cortex, with no expression in all other non-cortical brain regions and peripheral tissues tested. Our results suggest functional diversity for myosin II isozymes within the brain.


Subject(s)
Cerebral Cortex/metabolism , Myosins/genetics , Amino Acid Sequence , Animals , Base Sequence , Brain/metabolism , Cell Line , DNA Probes , Gene Library , Molecular Sequence Data , Neuroblastoma , Protein Conformation , Rats , Restriction Mapping , Sequence Homology, Nucleic Acid
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