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At least 577 records · Page 32Linked to original sources
PubMed2003

[Effect of exogenous epitopes of helper T lymphocyte on humoral immunity of HBV S gene DNA immunity].

OBJECTIVE: To study the effect of exogenous epitope of helper T lymphocyte (HTL) on humoral immunity of HBV S gene DNA immunity. METHODS: Two universal HTL epitopes, amino acid residue (aa) 830-843 of the tetanus toxoid (TTE) and artificial epitope (PADRE), and 3 unique epitopes, aa1-20 of tubercle bacteria hot shock protein 65 (TBE), aa54-65 of rubella protein E2-4 (ME) and aa35-48 of trachoma hot shock protein 60 (CE) were chosen. Eukaryotic expression vectors were constructed by inserting single or multiple exogenous epitopes in HBV S gene just after the initial code of translation. BALB/c mice were inoculated with 100 micro g of recombinant DNA per mouse, and given boost inoculation for 3 times with 3-week interval. Mouse blood were collected one month just after the third boost inoculation. Anti-HBs was detected using Abbott test kits. RESULTS: HBV S eukaryotic gene expression vectors, pHB and 6 exogenous HTL epitope HBV S gene vectors, pHB-TBE, pHB-PADRE, pHB-TTE, pHB-MTE2, pHB-MTE3 and pHB-MTE5 were constructed successfully with anti-HBs level (IU/L) of 10 +/- 5, 5 +/- 5, 49 +/- 7, 29 +/- 6, 16 +/- 8, 23 +/- 7 and 28 +/- 8 respectively. Among 3 single epitopes, TTE and PADRE had obviously effect on promoting the anti-HBs response of HBV S gene, while TBE had no promoting effect. All of the 3 multiple epitopes were shown the effect of immune promoting. CONCLUSION: Some exogenous HTL epitopes had obviously effect on promoting the anti-HBs response of HBV S gene. Multiple epitopes also had humoral immunity promoting effect, but there was no synergic effect among their own HTL epitopes. PADRE might be an important candidate for new efficient HB vaccine. The multiple epitope cluster consisted form 5 exogenous epitopes might be an important candidate for the reinoculating HB vaccine or therapy HB vaccine.

Animals↗
PubMed1992

Human protein-tyrosine kinase gene HCK: expression and structural analysis of the promoter region.

The vertebrate gene HCK encodes a protein-tyrosine kinase that is closely related to the product of the proto-oncogene SRC. HCK is expressed principally in monocytic and granulocytic hematopoietic cells, in coordination with differentiation of these cells. Here we report an initial description of the mechanisms by which expression of human HCK is controlled. Induction of the gene during differentiation was manifested by an increase in the steady-state levels of HCK RNA and protein product. The accumulation of RNA apparently resulted from modulation of transcription itself, since no change occurred in the stability of the transcripts. Transcription initiated at multiple sites, clustered c. 145 nucleotides upstream of the first intron of HCK. The sequence of 660 bp upstream of the major initiation site was determined, revealing candidate binding sites for Sp1 and AP-2 transcription factors, but neither TATA nor CAAT elements. Comparison to the same region of the mouse hck locus showed five small regions of similarity, only two of which were topographically analogous between the two sequences. It appears that expression of HCK is regulated primarily through control of transcription, but the mechanisms by which tissue-specific expression and increase of transcription during differentiation are achieved remain to be explored.

Base Sequence↗
PubMed1992

Cloning and characterization of the 5'-flanking region of the human topoisomerase II alpha gene.

Topoisomerases are essential enzymes for DNA metabolism in prokaryotes and eukaryotes. In human cells, DNA topoisomerase II enzyme activity can be modulated by both viral transformation and changes in proliferation status. To identify elements important for regulation of topoisomerase II alpha gene expression, genomic DNA clones covering the 5'-end of the gene were isolated. The intron/exon structure of a 2.5-kilobase region encompassing the translation start site was determined. Transcription was found to initiate at multiple sites clustered around 90 base pairs 5' to the ATG initiation codon. Transient expression of chimeric topoisomerase II-reporter gene constructs in HeLa cells revealed that the 5'-flanking region exhibited promoter activity. The region -90 to -1 upstream of the major transcription start site was shown by deletion analysis to include a promoter. This minimal promoter lacks a TATA box, is moderately GC-rich, and contains a high frequency of CpG dinucleotides; characteristic of a "housekeeping" gene promoter. Maximal promoter activity was observed using a fragment extending to position -562. Putative regulatory elements are contained within and immediately upstream of the minimal promoter region. The regulatory region of the topoisomerase II alpha gene identified here is similar in basic structure to those of the human thymidine kinase and DNA polymerase alpha genes, which are also controlled by proliferation-specific factors.

Base Sequence↗
PubMed2003

[The characteristics of carotid atherosclerosis in metabolic syndrome].

OBJECTIVE: To study the structure and function of the carotid artery in the metabolic syndrome (MS). METHODS: 171 patients were divided into three groups: metabolic syndrome (MS), diabetes mellitus (DM), and essential hypertension (EH). Plasma lipids and ultrasonography for carotid artery were examined. RESULTS: Levels of TG, LDL, ApoB were significantly higher in MS as compared with those EH (P < 0.01, 0.05, 0.01). Levels of TG were higher in MS as compared with those in DM (P < 0.01). The carotid resistance index and the intima-media thickness (IMT) of common carotid artery were significantly higher in MS as compared with those in DM or EH (P < 0.05). The occurrence rate of carotid plaque and plaque index was higher in patients with MS than that in patients with EH or DM (P < 0.01, 0.01). CONCLUSION: Clustering of multiple cardiovascular risk factors can cause more severe atherosclerosis of carotid artery in MS.

Adult↗
PubMed2003

Size and shape modifications in Sardinian adolescent girls.

In females, menarche is the defining moment of puberty, the period of life when the greatest body changes occur. In the present study, the metric and morphological variations associated with sexual maturation are defined in 155 Sardinian girls (10-17 years) and the role of some potentially influential variables is discussed: age, age at menarche and time since menarche. We studied thirty-eight anthropometric variables, the fat-free mass and the fat mass estimated by Bioelectrical Impedance Analysis. Statistical analyses were performed to evaluate the difference between pre- and post-menarcheal girls of the same age (Student's t-test) and to evaluate the different role played by the variables (principal components analysis, cluster analysis, multiple regression). The results demonstrate that the body dimensions of the adolescent girls mainly increase in concomitance with sexual maturation. The age at menarche influences the fat mass but not the distribution of visceral and subcutaneous fat. The time since menarche has also no effect on the distribution of subcutaneous fat.

Adolescent↗
PubMed2003

[Study on the prevalence of arthritis and relevant factors in Shanghai].

OBJECTIVE: This study aimed to understand the prevalence rate, epidemiological characteristics and relevant factors of arthritis in Shanghai. METHODS: A sample of 7 575 residents aged 15 years and above was drawn from 6 communities under multiple stage cluster sampling. A household survey with questionnaire was carried out to differentiate both undiagnosed patients and those with definite arthritis. Those who had not been diagnosed before were asked to carry further clinical examinations by a rheumatologist. RESULTS: The prevalence rate of arthritis was 6.11%, including osteoarthritis (OA) 4.18%, rheumatoid arthritis (RA) 0.52%, gout 0.28%, ankylosing spondylitis (AS) 0.28%, rheumatic arthritis 0.49% and other types arthritis 0.82%. Arthritis was significantly related to cardiovascular disease, pulmonary disease and gastrointestinal disease. Age, female and obesity might serve as risk factors for arthritis. Physical labors and living in rural area might have protecting effects. CONCLUSION: Elderly and female seemed to be at high risk for arthritis. Weight control and more exercise should be encouraged to reduce the risks. For arthritis patients, treatment to other chronic diseases should not be ignored.

Adolescent↗
PubMed2003

[Progress in the world health status of children during the period 1990-2000].

Multiple Indicator Cluster Surveys (MICS) conducted by UNICEF using standardized methods in 66 countries have provided data for evaluating the status of child health during the period between 1990 and 2000. This report presents findings on mortality in children less than 5 years of age, malnutrition indicators, immunization status and integrated management of childhood illness. It is concluded that children at the dawn of the 21st century are exposed to new risks related to poverty, war, violence, urbanization, and VIH/AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed2004

Child coverage with mosquito nets and malaria treatment from population-based surveys in african countries: a baseline for monitoring progress in roll back malaria.

We assessed the proportion of febrile children less than five years old with prompt effective antimalarial treatment and the proportion of those less than five years old sleeping under insecticide-treated nets (ITNs) or any mosquito net the preceding night in African malarious countries. Data were reviewed from 23 Multiple Indicator Cluster Surveys and 13 Demographic and Health Surveys conducted between 1998 and 2002. A median of 53% of febrile children received antimalarial treatment. A median of 84% of these treatments, however, involved chloroquine, and the proportion of treatments given within two days of onset of symptoms was unknown in most surveys. Median coverages of those less than five years old with any net and ITNs were 15% and 2%, respectively. Use of nets, and especially ITNs, was consistently lower in rural than in urban areas. At the outset of intensified malaria control under Roll Back Malaria, coverage with principal interventions was far below the target of 60% set for Africa in 2005.

Africa South of the Sahara↗
PubMedDate not supplied

[Morphology of oculomotor muscles and their nervous apparatus in lateral amyotrophic sclerosis in conditions during long-term artificial lung ventilation].

Light and electron microscopy, histochemical study of acetylcholinesterase (ACE) were used in examination of the state and innervation of ocular muscles in autopsy material from a patient who died of amyotrophic sclerosis (ATS). The patient had lived 14 years under artificial lung ventilation, ATS was diagnosed 22 years before the death. Light microscopy demonstrated the intactness of the muscle fibers and the presence of three types characteristic of the extraocular muscles: thin, granular and rough. Besides typical differences structural changes were observed in some muscle fibers of the myopathic character and inclusions not limited by membrane having filiform or granular structure. Ocular muscles had an intensive innervation. Nervous fiber terminals revealed by a reaction for ACE were represented by single motor plaques and multiple cluster-like endings. Ultrastructurally, nervous endings of two types differed by terminals and fold expression on the postsynaptic membrane. There were no pathological changes in axons and myelin. Thus, ocular muscles were not affected as well as their nervous apparatus at completion of AMS, this indicating the noninvolvement of this muscular allotype in a specific degenerative process.

Adolescent↗
PubMed2004

Coverage and costs of childhood immunizations in Cameroon.

OBJECTIVE: To quantify the association between household-level and provider-level determinants and childhood immunization rates in Cameroon while also calculating the cost of childhood immunizations. METHODS: This study uses multilevel regression analysis to calculate these relationships. The 1998 Cameroon Demographic and Health Survey and the 2000 Multiple Indicator Cluster Survey are the main sources of household-level data. These surveys are supplemented by data from a 2002 survey of health facilities conducted in three provinces. At the national level, immunization financing data were collected from the Ministry of Health and donors that support the national Expanded Programme on Immunization. FINDINGS: The 1998 survey found that nationally 37% of children were fully immunized; the 2000 survey found that nationally 34% were fully immunized. These results are strongly correlated with both the mother's level of education and the household's economic status. Multilevel logistic regression shows that maternal education level is a stronger predictor of positive immunization status than is relative economic status. Children of mothers with secondary education or higher education were 3 times more likely to be fully vaccinated than children whose mothers had not completed primary education. At the health-facility level, both having art immunization plan and regular supervisory visits from someone at the health-district level are strongly positively associated with immunization rates. The cost of routine vaccinations for each fully immunized child is 12.73 U.S. dollars when donors' contributions are included but not the costs of immunization campaigns. CONCLUSION: Studies conducted in the 1980s and 1990s found that costs per fully immunized child varied from 2.19 U.S. dollars to 26.59 U.S. dollars (not adjusted for inflation) in a range of low-income and middle-income countries. The relatively low rates of immunization coverage in Cameroon, and the strong influence of the household's socioeconomic status--particularly the mother's level of education--on immunization rates suggest that the effectiveness of the Cameroon programme could be increased by promoting immunization and directing such programmes towards households with limited resources.

Cameroon↗
PubMedDate not supplied

Giant axonal neuropathy in two siblings: clinical histopathological findings.

OBJECTIVE: Giant axonal neuropathy is a rare, severe autosomal-recessive neurologic disease affecting both the peripheral and the central nervous system. In this article, we describe a detailed clinicopathological report of two affected sibs from a consanguineous Turkish family. PATIENTS: The index patient was a 6.5-year-old girl. Her intellectual development was normal. At the age of 3, her parents noticed progressive lack of balance and deterioration of motor skills. On examination, she had paresis and sensory loss more marked distally. Her mental status was normal. Her older brother had similar findings. RESULTS: Electrophysiological studies of young patients showed decreased median and ulnar nerve conduction velocities, absent peroneal motor potential, absent sensory nerve potentials and an EMG suggesting a neurogenic pattern. MRI showed mild cerebral and cerebellar atrophy. The nerve biopsy showed moderate myelinated nerve fibres loss, several regenerative clusters and multiple giant axons. Focal demyelination, hypertrophic "onion pulp" changes and endoneural fibrosis were also seen. Immunohistochemically, neurofilament protein accumulation was detectable in giant axons. CONCLUSIONS: This consanguineous family with two affected siblings and healthy parents complies with autosomal-recessive inheritance in GAN. In the majority of reported GAN cases, CNS involvement is described early in the course of the disease, but these patients did not present any sign of CNS involvement. GAN is a rare genetic disease of childhood involving the central and peripheral nervous systems. The diagnosis is easy with clinical, electrophysiological, and histopathological features, if it has been done. Early diagnosis is important, because of possible prenatal diagnosis.

Adolescent↗
PubMed2005

[Observation on effects of hepatitis B vaccine immunization for 12 years in children in Beijing].

OBJECTIVE: To evaluate the long-term protective effects of hepatitis B vaccine after immunizing to the children for 12 years in Beijing. METHODS: The multiple stratified cluster sampling was used in this epidemiological survey. The sampling children's blood serum HBsAg, anti-HBs and anti-HBc were checked and measured by the solid phase radioimmunoassay (SPRIA). The serological level of these index and the causes of the children with HBsAg positive were analyzed. RESULTS: There were 2,419 cases 3-12 years-old children immunized with the hepatitis B vaccine in infant period were surveyed and the total HBsAg positive rate was 0.52%. The vaccine protective rate was 88.45% (95% CI: 65.67%-97.89%). The total anti-HBc positive rate was 2.21%, being no statistical significance among the age groups. The average anti-HBs positive rate of 3-6 years-old children immunized with gene recombining vaccine was 38.79% and descending greatly following the age's dropping. The geometric means of anti-HBs serological titer (GMT) was 52.83 mIU/ml, showing no statistical significance among the age groups. The average anti-HBs positive rate of 6-12 years-old children immunized with the blood rooting vaccine was 50.79%. The geometric means of anti-HBs serological titer (GMT) was 61.51 mIU/ml. There were no statistical significances among the age groups. Among the HBsAg positive children, more than 50% of the children's mothers were HBsAg positive also. CONCLUSIONS: The protective effects given by immunization were significant after the hepatitis B vaccine vaccination for 12 years in Beijing. The booster immunization was not necessary, because the HBsAg positive rate didn't ascend obviously as the immunization time prolonging. As the anti-HBs positive rate of children who were immunized by the gene recombining vaccine might be descending following the age's dropping greatly, we should strengthen the serological surveillance of hepatitis B. The main cause that the children became the HBsAg carrier should be a vertical transmission.

Child↗
PubMed2005

[Application of molecular biology for the discovery of biosynthetic genes of polyketide and peptide antibiotics produced by actinomycetes].

Actinomycetes are currently the main source of antibiotics. Genome sequencing reveals the presence in these organisms of multiple gene clusters for the synthesis of yet unidentified secondary metabolites. Technological advances in DNA isolation, cloning and sequencing, as well as development of bioinformatics, facilitate large scale search for new gene clusters in organisms with unknown genome sequence and in environmental DNA. Methods used for detection of polyketide synthase (PKS) and non-ribosomal peptide synthetase (NRPS) genes are described in this article. New PKS and NRPS genes give access to new biologically active natural products which can become drugs or substrates for chemical modifications. Even more inspiring is their use in combinatorial biosynthesis to produce a variety of compounds with rationally designed structures.

Actinobacteria↗
PubMed1991

Molecular genetics of human erythrocyte MiIII and MiVI glycophorins. Use of a pseudoexon in construction of two delta-alpha-delta hybrid genes resulting in antigenic diversification.

Human glycophorins alpha and delta (or A and B) specify the MNSs blood group antigens; they exhibit considerable structural variation among populations. We show that two variant phenotypes of Miltenberger class III and VI are encoded by similar hybrid glycophorin genes in a delta-alpha-delta arrangement. Restriction mapping identified altered fragments unique to the MiIII and MiVI genes. Genomic sequences spanning exons 2 to 4 of the two genes were obtained by allele-specific polymerase chain reaction. Restriction analysis and direct sequencing of the amplified DNA revealed that MiIII and MiVI genes are identical to the delta gene except that, in both, an internal segment of the delta gene has been replaced by its homologous counterpart of the alpha gene, resulting in a delta-alpha-delta hybrid structure. In the process of hybrid formation a portion of alpha exon 3 and intron 3, that carries a functional 5' splicing signal, has been fused to an exon-like sequence in the delta gene that retains a 3' but lacks a 5' splicing signal. These rearrangements created a composite exon resulting in the expression of the ordinarily unexpressed delta gene sequence and conferred the hybrid proteins with new antigenic specificities. The expression of this sequence in MiIII glycophorin is directly demonstrated by protein sequencing. MiIII and MiVI genes differ in the location of upstream (delta-alpha) and downstream (alpha-delta) breakpoints and in the length of sequence replacement. The delta-alpha breakpoints of the two genes occur at different locations within a 35-base pair sequence of exon 3 that is clustered with multiple inverted repeats, whereas the alpha-delta breakpoints reside downstream in two dissimilar blocks of sequences of intron 3. The minimal length of the delta gene sequence that has been replaced by the alpha gene is 55 base pairs in the MiIII gene and 131 base pairs in the MiVI gene. Such segmental DNA transfers may have proceeded unidirectionally through the mechanisms of gene conversion.

Amino Acid Sequence↗
PubMed1986

A taxonomic analysis of multihospital systems.

Research to date on multihospital systems has proved largely uninformative, in part because similarities and differences among these organizations have not been addressed systematically. Through numeric classification, this article identifies populations of multihospital systems that share similar organizational attributes. Drawing on McKelvey's classification theory, 16 organizational characteristics of 160 multihospital systems are analyzed using a series of taxonomic techniques, including cluster analysis, multiple discriminant analysis, and analysis of coefficients of variation. Fifteen distinct subgroups of systems are identified and described, and their implications for organization research discussed.

Catholicism↗
PubMed1993

Anatomical and functional changes in the organization of the cuneate nucleus of adult rats after fetal forelimb amputation.

A previous study has shown that fetal forelimb removal in the rat results in an increase in the size of the hindlimb representation in primary somatosensory cortex and suggested that this anomalous cortical organization may have resulted from alterations in the primary afferent innervation of the dorsal column nuclei (Killackey and Dawson, 1989). The present study used both anatomical and electrophysiological techniques to examine the effects of fetal forelimb amputation on the dorsal column nuclei. Rats sustained forelimb removals on embryonic day 16 and were used in terminal experiments when they reached adulthood (> 60 d of age). Analysis of cytochrome oxidase-stained sections demonstrated that the cuneate nucleus ipsilateral to the lesion decreased in volume by an average of 36.7% (N = 7, p < 0.001, paired t test), but there was no corresponding increase in the volume of the gracile fasciculus and nucleus. Bilateral application of HRP to the sciatic nerves demonstrated that axons that innervate only the gracile nucleus on the intact side of the brainstem were present in the cuneate nucleus on the deafferented side. Injection of HRP into the skin overlying the point of the amputation (the stump) indicated that axons innervating this region filled most of the dorsal one-half of the shrunken cuneate nucleus and overlapped with the sciatic nerve afferents innervating the cuneate on this side. Mapping the receptive fields of multiple unit clusters demonstrated that most recording sites in the shrunken cuneate nucleus were activated by inputs from the stump and adjacent skin. In addition, 9.1% (N = 30) of such unit clusters (N = 328) could also be excited by stimulation of the hindlimb. These were observed in only three of the nine experiments. Unit clusters with split receptive fields including the skin overlying the stump and the hindlimb were located throughout the rostrocaudal extent of the cuneate nucleus. These results indicate that fetal forelimb amputation results in anatomical expansion of the central projections of hindlimb afferents into the cuneate nucleus. This anatomical organization appears weakly expressed in the receptive fields of cuneate neurons.

Afferent Pathways↗
PubMed1993

[CHARGE association: report of a case with literature review].

The CHARGE association was described as a cluster of multiple congenital defects by Pagon et al in 1981. The underlining cause of this association is not yet clear. These defects include coloboma of the eye tissues (C), heart disease (H), atresia choanae (A), retarded growth and development and/or CNS anomalies (R), genital anomalies (G), ear anomalies and/or hearing loss (E). Here we report a case of CHARGE association in a 15-year-old female patient. She presented with unilateral ptosis and coloboma of the iris, choroid and retina, patent ductus arteriosus, growth and mental retardation, unilateral ear deformity and a hearing loss. A total of 124 cases have been reported up to now in the literature. We also discuss the frequency of the respective clinical symptoms and signs, and the leading causes of misdiagnosis. We emphasize the importance of ophthalmology and ENT consultations whenever a patient is noted to have multiple congenital anomalies, especially when a cardiac defect is present. Early diagnosis and treatment are essential for this rare association.

Abnormalities, Multiple↗
PubMed1994

[A community cohort study on risk factors of strokes in Shanghai: a Cox regression analysis on 15,885 subjects].

Baseline investigation on 15,885 subjects who were over thirty-five years old had been launched since July 1987. All of them were selected from eighteen neighbourhoods of three districts in Shanghai by using multiple stage cluster sampling procedure. All of them were followed up till the end of 1989. Each new case of stroke was randomly matched with about twenty controls by age and sex. The total 2,682 controls together with 127 new cases of strokes were analyzed by using Cox regression model for risk factors. The population attributable risk proportion (PARP) of factors was also estimated.

Acute Disease↗