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1.

SUMMARY

The clinical outcome of infection with Leishmania species of the subgenus Viannia in hamster model (Mesocricetus auratus) has shown to be different depending on experimental protocol. Body weight has been a relevant determinant of the clinical outcome of the infection in hamsters with visceral leishmaniasis but its importance as a clinical parameter in hamsters with cutaneous leishmaniasis is not known. In this study, the clinical evolution of infection with L. (V) panamensis was evaluated in juvenile and adult male hamsters during 11 weeks by comparing clinical parameters such as attitude, temperature, respiratory rate, appearance of the stool, and body weight between infected and non-infected groups. Results showed that body weight decreased in adult hamsters after infection by L. (V) panamensis; this observation supports the use of body weight as an additional parameter to define the management or treatment of cutaneous leishmaniasis in infected adult hamsters used as an animal experimental model for leishmaniasis.  相似文献   

2.
We show that the genetic transformation of Nicotiana tabacum can be achieved by bombarding intact cells and tissues with DNA-coated particles. Leaves or suspension culture cells were treated with tungsten microprojectiles carrying plasmid DNA containing a neomycin phosphotransferase gene. Callus harboring the foreign gene was recovered from the bombarded tissue by selection on medium containing kanamycin. Kanamycin-resistant plants have subsequently been regenerated from the callus derived from leaves. Transient expression of an introduced β-glucuronidase gene was used to assess the efficiency of DNA delivery by microprojectiles. The frequency of cells that were stably transformed with the neomycin phosphotransferase gene was a few percent of the cells that transiently expressed the β-glucuronidase gene. These results show that gene transfer by high-velocity microprojectiles is a rapid and direct means for transforming intact plant cells and tissues that eliminates the need for production of protoplasts or infection by Agrobacterium.  相似文献   

3.
In contrast to acute lymphoblastic leukemia in children, adult cases of this disease are associated with a very poor prognosis. In order to ascertain whether the frequencies and patterns of submicroscopic changes, identifiable with single nucleotide polymorphism array analysis, differ between childhood and adult acute lymphoblastic leukemia, we performed single nucleotide polymorphism array analyses of 126 adult cases, the largest series to date, including 18 paired diagnostic and relapse samples. Apart from identifying characteristic microdeletions of the CDKN2A, EBF1, ETV6, IKZF1, PAX5 and RB1 genes, the present study uncovered novel, focal deletions of the BCAT1, BTLA, NR3C1, PIK3AP1 and SERP2 genes in 2–6% of the adult cases. IKZF1 deletions were associated with B-cell precursor acute lymphoblastic leukemia (P=0.036), BCR-ABL1-positive acute lymphoblastic leukemia (P<0.001), and higher white blood cell counts (P=0.005). In addition, recurrent deletions of RASSF3 and TOX were seen in relapse samples. Comparing paired diagnostic/relapse samples revealed identical changes at diagnosis and relapse in 27%, clonal evolution in 22%, and relapses evolving from ancestral clones in 50%, akin to what has previously been reported in pediatric acute lymphoblastic leukemia and indicating that the mechanisms of relapse may be similar in adult and childhood cases. These findings provide novel insights into the leukemogenesis of adult acute lymphoblastic leukemia, showing similarities to childhood disease in the pattern of deletions and the clonal relationship between diagnostic and relapse samples, but with the adult cases harboring additional aberrations that have not been described in pediatric acute lymphoblastic leukemia.  相似文献   

4.
A diuretic hormone (DH) has been isolated from pharate adult heads of Manduca sexta by a nine-step purification procedure. The primary structure of the amino-terminal 40 residues was determined by sequence analysis of intact DH. The structure of an amidated carboxyl-terminal tryptic hexapeptide was characterized by sequence analysis of the peptide, and this hexapeptide was later compared by reversed-phase liquid chromatography with two synthetic hexapeptides with the free acid or amide at the carboxyl terminus. The complete structure of M. sexta DH was established as a 41-residue peptide without disulfide bonds: H-Arg-Met-Pro-Ser-Leu-Ser-Ile-Asp-Leu-Pro-Met-Ser-Val-Leu-Arg-Gln-Lys-Leu-Ser -Leu-Glu-Lys-Glu-Arg-Lys-Val-His-Ala-Leu-Arg-Ala-Ala-Ala-Asn-Arg-Asn-Phe-Leu- Asn-Asp-Ile-NH2. M. sexta DH was synthesized and shown to have chromatographic and biological properties identical with those of the native material. Synthetic DH stimulated fluid excretion in vivo upon injection into larval M. sexta and newly emerged adult Pieris rapae. M. sexta DH has considerable sequence homology with corticotropin-releasing factor, urotensin I, and sauvagine.  相似文献   

5.
Acute focal bacterial nephritis (AFBN) is a rare, acute focal infection of the renal parenchyma without liquefaction. The pathogenesis is thought to be due to hematogenous infection or ascending infection from the lower urinary tract. Escherichia coli has been the major pathogen isolated in prior cases, but other Gram-negative enteric pathogens and Staphylococcus aureus have been reported as well. It is well described in children and adults with diabetes and organ transplantation, but has not been previously reported in healthy adults. We report a case of an immunocompetent adult female who presented with a methicillin-resistant Staphylococcus aureus bacteremia after a skin and soft tissue infection that resulted in AFBN.  相似文献   

6.
There is a clear need to perform epidemiological studies to find the true prevalence of Entamoeba histolytica around the world. The evaluation of this prevalence has been hindered by the existence of two different species which are morphologically identical, but genetically different, namely E. histolytica, which causes amebiasis, and E. dispar, which is non-pathogenic. In Brazil, the E. dispar has been detected in communities in the Southeastern (SE) and Northeastern (NE) regions with poor sanitation. However, individuals infected with E. histolytica have been identified in other regions. There is an absence of reports on the prevalence of these parasites in the state of Paraíba, which also has areas with poor sanitary conditions where a high prevalence of the E. histolytica/E. dispar complex has been detected in children from urban slums. The present study evaluated the prevalence of E. histolytica and E. dispar in 1,195 asymptomatic children between two and 10 years of age, living in a sprawling urban slum in Campina Grande, in the state of Paraíba, in Northeastern Brazil. These children were examined and their feces samples were analyzed microscopically. A total of 553 children tested positive for the E. histolytica/E. dispar complex, and 456 of the positive samples were tested with the E. histolytica II® ELISA kit. All 456 samples were negative for the presence of the adhesin E. histolytica specific antigen. The evidence suggests that in this community E. histolytica is absent and E. dispar is the dominant species.  相似文献   

7.
8.
应用RT-PCR方法分别从新疆株细粒棘球绦虫原头蚴和成虫中克隆出Eg Ras GTPase基因,分别命名为Eg Ras-pro(GenBank登录号为EU560397)和Eg Ras-adult(GenBank登录号为EU560398)。 生物信息学分析表明两者cDNA长度均为552 bp,编码184个氨基酸,等电点(pI)为6.54,彼此间仅有2个碱基和1个氨基酸的差别。同源性比对分析结果显示,Eg Ras-pro和Eg Ras-adult与多房棘球绦虫Ras(EmRas)基因的同源性分别高达98.4%和98.9%;与其他种类的寄生虫、酵母、果蝇及人类的Ras GTPase基因的同源性为53.9%~78.8%。进化树分析发现Eg Ras-pro和Eg Ras-adult与EmRas和血吸虫Ras(SmRas)相聚集。本研究首次从新疆株细粒棘球绦虫两个发育阶段(原头蚴和成虫)中克隆出Eg Ras GTPase基因,其序列具有较高的保守性。  相似文献   

9.
10.
The prevalence of convenience-driven delivery via Caesarian-section (C-section) has been steadily increasing in Western as well as in developing societies. Today, significantly more deliveries occur via surgical means than medical necessity mandates. Despite tremendous advances in surgical techniques and pre- and post-operative surgical care, there remains to be limited understanding on the physiological influence of vaginal birth with particular emphasis on long term outcome on the offspring. Serendipitously, we recently uncovered in mice that vaginal birth induces significantly higher level of Ucp2 mRNA expression in the hippocampus than experimental C-section. We showed that during the early postnatal period, UCP2 expression promotes neuronal differentiation, axonal outgrowth and synapse formation in the hippocampus. We also observed that Ucp2 knockout animals show adult behaviors associated with the hippocampal formation that is different from wild type littermates. Taken together these observations suggest that vaginal birth may play a crucial role in determining adult brain structure and function that is different from that of the effect of surgically assisted birth.  相似文献   

11.
The susceptibility to respiratory syncytial virus (RSV) infection in early life has been associated with a deficient T-helper cell type 1 (Th1) response. Conversely, healthy adults generally do not exhibit severe illness from RSV infection. In the current study, we investigated whether Th1 cytokine IFN-γ is essential for protection against RSV and RSV-associated comorbidities in adult mice. We found that, distinct from influenza virus, prior RSV infection does not induce significant IFN-γ production and susceptibility to secondary Streptococcus pneumoniae infection in adult wild-type (WT) mice. In ovalbumin (OVA)-induced asthmatic mice, RSV super-infection increases airway neutrophil recruitment and inflammatory lung damage but has no significant effect on OVA-induced eosinophilia. Compared with WT controls, RSV infection of asthmatic Ifng−/− mice results in increased airway eosinophil accumulation. However, a comparable increase in eosinophilia was detected in house dust mite (HDM)-induced asthmatic Ifng−/− mice in the absence of RSV infection. Furthermore, neither WT nor Ifng−/− mice exhibit apparent eosinophil infiltration during RSV infection alone. Together, these findings indicate that, despite its critical role in limiting eosinophilic inflammation during asthma, IFN-γ is not essential for protection against RSV-induced exacerbation of asthmatic inflammation in adult mice.  相似文献   

12.
13.
BackgroundStevens-Johnson syndrome (SJS) associated with Mycoplasma pneumoniae (M. pneumoniae) infection is mainly observed in children. In adults, drugs are a major cause of SJS, but some adult patients with SJS are infected with M. pneumoniae. We analyzed patients with SJS associated with M. pneumoniae infection to elucidate the differences between drug-induced SJS and M. pneumoniae-associated SJS and also to study differences between M. pneumoniae-associated SJS in children and adults.MethodsThis is a retrospective review of Japanese patients who have been reported as M. pneumoniae-associated SJS in medical Journals published from 1981 to 2009, compared with data of Japanese patients with drug-induced SJS reported from 2000 to 2009.ResultsThirty-eight cases of M. pneumoniae-associated SJS and 78 cases of drug-induced SJS were analyzed in this study. Ocular lesions were observed more frequently in M. pneumoniae-associated SJS than in drug-induced SJS (p < 0.01), and adult patients showed a higher ratio of sequelae in their eyes than did patients under 20 years of age (p < 0.01). Sixty-six percent of adult patients with M. pneumoniae-associated SJS developed fever/respiratory symptoms and mucocutaneous lesions on the same day. In contrast, most of the patients under 20 years of age developed fever/respiratory symptoms before mucocutaneous involvement. This means that these adult patients were infected and immunized previously and developed allergic reactions to M. pneumoniae soon after the later infection.ConclusionsIn order to prevent ocular sequelae in adult patients when M. pneumoniae infection is suspected, more intensive treatment may be needed in adult patients than in younger patients.  相似文献   

14.
The molecular defects responsible for tumorigenesis in adult de novo acute myeloid leukemia (AML) with a normal karyotype or an additional copy of one chromosome (i.e., trisomy) remain largely unknown. We recently discovered that approximately 90% of adult patients with de novo AML and trisomy 11 (+11) as a sole abnormality and 11% of adult patients with de novo AML and normal cytogenetics carry a molecular rearrangement of the ALL1 (MLL, HRX, or HTRX) gene. The rearranged ALL1 gene has been shown to result from the direct tandem duplication of a portion of ALL1 itself. To better understand the underlying mechanisms of leukemogenesis, we asked whether in cytogenetically normal cases one or both chromosomes carry the mutated allele and whether in trisomic cases the mutation is present in one, two, or three chromosomes. Herein we show that in cytogenetically normal cases of AML and in cases with +11 as a sole cytogenetic abnormality, only one chromosome contains the mutated ALL1 allele. Thus a single mutated ALL1 allele with the partial tandem duplication is sufficient for ALL1-associated leukemogenesis, irrespective of the number of normal genes present. The frequently occurring specific association of +11 and ALL1 gene mutation in the leukemic clone remains unexplained.  相似文献   

15.
BackgroundMinor progress in pancreatic cancer treatment and prognosis implies that more reliable animal models are urgently needed to decipher its molecular mechanisms and preclinical research. We recently reported a genetically engineered adult mouse model where Cdkn2b downregulation was required together with Cdkn2a downregulation to inactivate the Rb pathway. Besides, the role of Smad4, which is mutated more frequently than Cdkn2b in human pancreatic cancer, was determined critical on the development of the pancreas tumor by some reports. However, the impact of Smad4 deficiency in combination with PDAC-relevant mutations, such as Cdkn2a when induced in adult pancreas has not been completely elucidated in mice.MethodsLentiviral delivered oncogene/tumor suppressors in adult pancreas. The development of pancreatic cancer was monitored. Hematoxylin and eosin staining and immunofluorescence were performed for pathological identification of the pancreatic cancer. Real-time polymerase chain reaction, immunofluorescence and western blot were used to test gene expression.ResultsLoss of Smad4 could cooperate with alterations of KRAS, Trp53, and Cdkn2a to induce pancreatic cancer in adult mice. The role of Smad4 was mainly in downregulating the expression of Cdkn2b and further inducing phosphorylation of the Rb1 protein.ConclusionsThese findings show an essential role of Smad4 deficiency in pancreatic ductal adenocarcinoma (PDAC) formation. This model better recapitulates the adult onset, clonal origin, and genetic alterations in human PDAC and can be simply generated on a large-scale.  相似文献   

16.

SUMMARY

The dermatophytes, keratinophilic fungi, represent important microorganisms of the soil microbiota, where there are cosmopolitan species and others with restricted geographic distribution. The aim of this study was to broaden the knowledge about the presence of dermatophytes in soils of urban (empty lots, schools, slums, squares, beaches and homes) and rural areas and about the evolution of their prevalence in soils of varying pH in cities of the four mesoregions of Paraiba State, Brazil. Soil samples were collected from 31 cities of Paraiba State. Of 212 samples, 62% showed fungal growth, particularly those from the Mata Paraibana mesoregion (43.5%), which has a tropical climate, hot and humid. Soil pH varied from 4.65 to 9.06, with 71% of the growth of dermatophytes occurring at alkaline pH (7.02 - 9.06) (ρ = 0.000). Of 131 strains isolated, 57.3% were geophilic species, particularly Trichophyton terrestre (31.3%) and Mycrosporum gypseum (21.4%). M. nanum and T. ajelloi were isolated for the first time in Paraiba State. The zoophilic species identified were T. mentagrophytes var. mentagrophytes (31.3 %) and T. verrucosum (7.6 %), and T. tonsurans was isolated as an anthropophilic species. The soils of urban areas including empty lots, schools, slums and squares of cities in the mesoregions of Paraiba State were found to be the most suitable reservoirs for almost all dermatophytes; their growth may have been influenced by environmental factors, soils with residues of human and/or animal keratin and alkaline pH.  相似文献   

17.
The amino acid sequence of the first 133 residues of the heavy (γ) chain from a human γG immunoglobulin (He) has been determined. This γ-chain is identical in Gm type to that of protein Eu, the complete sequence of which has been reported. Comparison of the two sequences substantiates the previous suggestion that there are subgroups of variable regions of heavy chains. The variable region of Eu has been assigned to subgroup I and that of He to subgroup II; on the other hand, the constant regions of the two proteins appear to be identical. Comparison of the sequence of the heavy chain of He with the heavy chain sequences determined in other laboratories suggests that the variable region of subgroup II is at least 118 residues long. The nature and distribution of amino acid variations in this heavy chain subgroup resemble those observed in light chain subgroups.

These studies provide evidence that the translocation hypothesis applies to heavy as well as to light chains, viz., genes for variable regions (V) are somatically translocated to genes for constant regions (C) to form complete VC structural genes.

  相似文献   

18.
目的 表达亚洲带绦虫(Taenia asiatica,Ta)成虫烯醇化酶(enolase,ENO)基因,并对其进行组织定位和免疫反应性分析。 方法 通过大规模测序从亚洲带绦虫cDNA文库中确定ENO基因,PCR扩增目的片段,将其克隆至表达质粒pET-30a(+),在大肠埃希菌BL-21/DE3中用异丙基-β-D-硫代半乳糖苷(IPTG)诱导表达,十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)观察重组蛋白的表达情况,用镍离子金属螯合剂亲和层析柱纯化重组蛋白,蛋白质印迹(Western blotting)分析该重组蛋白的免疫反应性。将重组蛋白免疫SD大鼠制备免疫血清,ELISA检测抗体水平,间接免疫荧光检测确定ENO在亚洲带绦虫成虫组织中的定位。 结果 PCR、双酶切和DNA测序结果均表明,重组质粒pET-30a(+)-TaENO构建成功。SDS-PAGE结果显示,重组蛋白TaENO的相对分子质量(Mr)为47 000。经亲和层析获高纯度的蛋白,蛋白浓度为0.37 mg/ml。重组蛋白TaENO能被SD大鼠抗血清、感染亚洲带绦虫的猪血清和患者血清识别。间接免疫荧光检测结果显示,TaENO主要定位于成虫的表膜。 结论 纯化后的亚洲带绦虫成虫烯醇化酶重组蛋白具有较强的免疫反应性,烯醇化酶主要定位于成虫表膜。  相似文献   

19.
Tail resorption during amphibian metamorphosis has been thought to be controlled mainly by a cell-autonomous mechanism of programmed cell death triggered by thyroid hormone. However, we have proposed a role for the immune response in metamorphosis, based on the finding that syngeneic grafts of tadpole tail skin into adult Xenopus animals are rejected by T cells. To test this, we identified two tail antigen genes called ouro1 and ouro2 that encode keratin-related proteins. Recombinant Ouro1 and Ouro2 proteins generated proliferative responses in vitro in T cells isolated from naive adult Xenopus animals. These genes were expressed specifically in the tail skin at the climax of metamorphosis. Overexpression of ouro1 and ouro2 induced T-cell accumulation and precocious tail degeneration after full differentiation of adult-type T cells when overexpressed in the tail region. When the expression of ouro1 and ouro2 were knocked down, tail skin tissue remained even after metamorphosis was complete. Our findings indicate that Ouro proteins participate in the process of tail regression as immune antigens and highlight the possibility that the acquired immune system contributes not only to self-defense but also to remodeling processes in vertebrate morphogenesis.  相似文献   

20.

Background

Differences in survival have been reported between pediatric and adult acute lymphoblastic leukemia. The inferior prognosis in adult acute lymphoblastic leukemia is not fully understood but could be attributed, in part, to differences in genomic alterations found in adult as compared to in pediatric acute lymphoblastic leukemia.

Design and Methods

We compared two different sets of high-density single nucleotide polymorphism array genotyping data from 75 new diagnostic adult and 399 previously published diagnostic pediatric acute lymphoblastic leukemia samples. The patients’ samples were randomly acquired from among Caucasian and Asian populations and hybridized to either Affymetrix 50K or 250K single nucleotide polymorphism arrays. The array data were investigated with Copy Number Analysis for GeneChips (CNAG) software for allele-specific copy number analysis.

Results

The high density single nucleotide polymorphism array analysis of 75 samples of adult acute lymphoblastic leukemia led to the identification of numerous cryptic and submicroscopic genomic lesions with a mean of 7.6 genomic alterations per sample. The patterns and frequencies of lesions detected in the adult samples largely reproduced known genomic hallmarks detected in previous single nucleotide polymorphism-array studies of pediatric acute lymphoblastic leukemia, such as common deletions of 3p14.2 (FHIT), 5q33.3 (EBF), 6q, 9p21.3 (CDKN2A/B), 9p13.2 (PAX5), 13q14.2 (RB1) and 17q11.2 (NF1). Some differences between adult and pediatric acute lymphoblastic leukemia were identified when the pediatric data set was partitioned into hyperdiploid and non-hyperdiploid cases and then compared to the nearly exclusively non-hyperdiploid adult samples. In this analysis, adult samples had a higher rate of deletions of chromosome 17p (TP53) and duplication of 17q.

Conclusions

Our analysis of adult acute lymphoblastic leukemia cases led to the identification of new potential target lesions relevant for the pathogenesis of acute lymphoblastic leukemia. However, no unequivocal pattern of submicroscopic genomic alterations was found to separate adult acute lymphoblastic leukemia from pediatric acute lymphoblastic leukemia. Therefore, apart from different therapy regimen, differences of prognosis between adult and pediatric acute lymphoblastic leukemia are probably based on genetic subgroups according to cytogenetically detectable lesions but not focal genomic copy number microlesions.  相似文献   

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