ABSTRACT
The formation, consolidation and retrieval of spatial memory depend on sequential firing patterns of place cells assembling in the hippocampus. Theta sequences of place cells during behavior play a role in acquisition of spatial memory, trajectory prediction and decision making. In awake rest and slow wave sleep, place cell sequences occur during the sharp wave-ripples (SWRs), called "replay", which is crucial for memory consolidation and retrieval. In this review, we summarize the functional significances of theta sequences and SWRs replay sequences and the mechanism of these sequences. We also discuss the relationship between theta and replay sequences with the formation of spatial memory. We propose the research direction in this field in future and aim to provide new ideas for related researches.
Subject(s)
Hippocampus , Sleep , Spatial Memory , WakefulnessABSTRACT
<p><b>OBJECTIVE</b>To investigate the genotypes and clinical features of children with HbH disease in Guangxi Zhuang Autonomous Region, China.</p><p><b>METHODS</b>A total of 595 children from Guangxi were recruited. Single-tube multiplex polymerase chain reaction combined with agarose gel electrophoresis, as well as reverse dot blotting, were performed to detect the three α-globin gene deletion mutations (--(SEA), -α(3.7), and -α(4.2)) and three non-deletion mutations (Hb Westmead, Hb Constant Spring, and Hb Quong Sze) which are common in the Chinese population.</p><p><b>RESULTS</b>Among the 595 cases, five common genotypes were identified, which were --(SEA)/-α(3.7) (232 cases), --(SEA)/α(CS)α (174 cases), --(SEA)/-α(4.2) (122 cases), --(SEA)/α(WS)α (35 cases), and --(SEA)/α(QS)α (24 cases). The genotype of THAI deletion associated with α-thalassemia-2 was detected in eight cases. Six β-mutations including CD41-42, CD17-28, CD26, IVS-II-654, IVS-I-1, and CD27-28 were identified in 23 cases. All children with HbH disease had microcytic hypochromic anemia; children with HbH-CS disease had the most severe anemia, and those with HbH-WS disease had the mildest anemia.</p><p><b>CONCLUSIONS</b>Deletional HbH disease is the main type in children with HbH disease in Guangxi, and some patients also have mild beta-thalassemia. Non-deletional HbH disease shows more severe phenotype than deletional HbH disease.</p>
Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Infant , Male , Genotype , Hemoglobin H , Genetics , Multiplex Polymerase Chain Reaction , alpha-Thalassemia , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To study the relationship between abnormal karyotypes and clinical phenotypes among children in genetic counseling in Guangxi Zhuang Autonomous Region, China.</p><p><b>METHODS</b>We studied 601 children who visited Guangxi Zhuang Autonomous Region Women and Children Care Hospital for genetic counseling between January 2009 and July 2012. Blood samples were cultured routinely for karyotype analysis with G banding as well as clinical analysis.</p><p><b>RESULTS</b>Out of 601 patients, 329 (54.7%) had chromosomal abnormalities, and 8 new abnormal human karyotypes were found. Among 329 children with abnormal karyotypes, 317 (96.4%) had an abnormal number of chromosomes, and 12 (3.6%) had abnormal chromosomal structure. Abnormal karyotypes were clinically manifested by Down's syndrome (74.5%), growth retardation (10.9%), and mental retardation (3.0%).</p><p><b>CONCLUSIONS</b>Eight rare abnormal karyotypes were found in the study, providing new resources for the genetic studies and etiological analysis of growth retardation, mental retardation, gonadal dysgenesis, and multiple congenital anomalies in children.</p>
Subject(s)
Humans , Abnormalities, Multiple , Genetics , Chromosome Aberrations , Genetic Counseling , Intellectual Disability , Genetics , KaryotypeABSTRACT
<p><b>OBJECTIVE</b>To assess the association between SIRT1 gene polymorphisms and the longevity phenomena in Yongfu region of Guangxi. In this case-control study, 500 individuals from Yongfu region of Guangxi were recruited. The subjects were divided into a longevity group (n=223, average age=93.17 U+00B1 3.08 yr) and a healthy control group (n=277, average age=46.92 U+00B1 17.12 yr). Polymerase chain reaction-high resolution melting curve (PCR-HRM) and DNA sequencing were used to determine the allelic and genotypic frequencies of rs3758391, rs3740051, rs2273773, rs4746720 and rs10997870 polymorphisms of SIRT1 gene in the two groups. The association between above polymorphisms and longevity was assessed.</p><p><b>RESULTS</b>In the longevity group, CT genotype of the rs4746720 locus was significantly more common than CC and TT genotypes (P=0.000, OR=2.098, 95%CI:1.412-4.117). However, no significant difference was found in the allelic and genotypic frequencies of rs3758391, rs3740051 and rs2273773 between the two groups.</p><p><b>CONCLUSION</b>There is an association between rs4746720 of SIRT1 gene and longevity in Yongfu region of Guangxi.</p>
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult , Alleles , Asian People , Genetics , Base Sequence , Case-Control Studies , China , Gene Frequency , Gene Order , Genetic Association Studies , Genotype , Longevity , Genetics , Polymorphism, Single Nucleotide , Sirtuin 1 , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To investigate the human mitochondrial DNA (mtDNA) variations associated with longevity in Bama elderly population from Guangxi.</p><p><b>METHODS</b>Mitochondrial genome of 20 individuals over 96 years of age was sequenced, and seven target single nucleotide polymorphism (SNPs) were observed by comparing with the standard rCRS sequence, and two were tested by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in a larger population including 208 individuals of 90-113 years old, and 586 unrelated control individuals from Guangxi.</p><p><b>RESULTS</b>The 4824G frequency of the mtDNA4824A/G locus increased with age both in the long-lived elderly and in controls. And it was significantly higher in controls than that in long-lived population (P<0.05).</p><p><b>CONCLUSION</b>The mtDNA4824 A/G is not only an age-related locus, its mutation is also negatively correlated with longevity.</p>
Subject(s)
Aged , Humans , China , Ethnology , DNA, Mitochondrial , Genetics , Genome, Mitochondrial , Genetics , Haplotypes , Longevity , Genetics , Mutation , Myanmar , Ethnology , Polymorphism, Genetic , Polymorphism, Restriction Fragment Length , Polymorphism, Single Nucleotide , Genetics , Population GroupsABSTRACT
Objective:To study the relation between the distribution ofapolipoprotein E(apoE)genotypes and cognitive impairment onset in long lived elderly in Bama area in Guangxi in china.Methods:A total of 112 long lived elderly aged 90 years old and over were collected and tested with MMSE to inspect their cognitive function,and they were classified into cognition impaired group and non-impaired group according to MMSE scores.We determined the AopE genotypes by way of PCR-RFLP technique,and compared the differences of AopE allele and genotype of the two groups.Result:The cognitive disfunction was found to be 14.29% in long lived elderly in Bama area.The ApoE ? 3/? 3 genotypes have highest frequency in long-lived elderly,next is ?2/3,and ?4/4 is lowest frequency.There were significant differences of ? 4 allele frequencies between cognition impaired group and non-impaired group(P