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141.

Background  

Factor XI (FXI) is a plasma protein that participates in the formation of blood clots. Factor XI deficiency is autosomal recessive hereditary disorder that may be associated with excess bleeding in Holstein cattle.  相似文献   
142.
Orthopoxviruses commonly enter into humans and animals via the respiratory tract. Herein, we show that immigration of leukocytes into the lung is triggered via intranasal infection of mice with modified vaccinia virus Ankara (MVA) and not with the vaccinia virus (VACV) Elstree, Wyeth, or Western Reserve (WR) strain. Immigrating cells were identified as monocytes, neutrophils, and CD4+ lymphocytes by flow cytometry and could be detected 24 h and 48 h postinfection. Using an in vitro chemotaxis assay, we confirmed that infection with MVA induces the expression of a soluble chemotactic factor for monocytes, identified as CCL2 (monocyte chemotactic protein-1 [MCP-1]). In contrast to infection with several other VACV strains, MVA induced the expression of CCL2, CCL3, CCL4, and CXCL10 in the human monocytic cell line THP-1 as well as in primary human monocytes. Thus, MVA, and not the VACV Elstree, Wyeth, or WR strain, consistently triggered the expression of a panel of chemokines, including CCL2, in the murine lung, correlating considerably with the immigration of leukocytes. Using CCL2-deficient mice, we demonstrate that CCL2 plays a key role in MVA-triggered respiratory immigration of leukocytes. Moreover, UV irradiation of MVA prevented CCL2 expression in vitro and in vivo as well as respiratory immigration of leukocytes, demonstrating the requirement for an activated molecular viral life cycle. We propose that MVA-triggered chemokine expression causes early immigration of leukocytes to the site of infection, a feature that is important for rapid immunization and its safety and efficiency as a viral vector.The World Health Organization (WHO) announced the worldwide eradication of smallpox at the end of the 1970s. Nevertheless, the threat of an outbreak of smallpox or a smallpox-like disease, either by natural means or via bioterrorism, exists to this day. This danger was illustrated in 2003 by the mini-epidemic of monkeypox in the U.S. Midwest (33). Thus, a vaccine against smallpox is, even today, essential. Although vaccination against smallpox using vaccinia virus (VACV) was quite successful, the incidence of severe side effects prompted the WHO to discontinue the use of the vaccine. Therefore, there is currently still a need for an effective and safe vaccine against smallpox.Among the orthopoxviruses, VACV is frequently used to study poxvirus infection, since it displays many properties of variola virus, the etiologic agent of smallpox, including the capability of modulating and suppressing the immune system by means of expressing several immunoregulatory proteins (44). The assumed natural primary infection site of variola virus is considered to be the respiratory tract (5). Here, the virus encounters lung epithelial cells, conventional dendritic cells, and macrophages. More than three decades ago, viral antigen was detected in alveolar macrophages after a sublethal infection of rabbits with inhaled VACV by using immunofluorescence assays (3). Additionally, under the electron microscope, the cells obtained from repeated washing of rabbit lungs demonstrated that VACV infects and replicates exclusively in macrophages (18). Macrophages, the most abundant hematopoietic cell type in the lung, play a key role in antiviral immune defense through the phagocytosis of infectious particles and the production of reactive oxygen species as well as leukotrienes and inflammatory cytokines (14).The coordinated migration, differentiation, and activation of dendritic cells as well as lymphocytes are required for the efficient elimination of microbes, including viruses, from the lung (15). Activated alveolar macrophages, in particular, enhance the cellular immune response by triggering the immigration of several leukocyte types into the lung owing to the production of chemokines (35). The importance of alveolar macrophages in limiting the replication of a recombinant VACV strain Western Reserve (WR) was recently demonstrated with mice (38). It is likely that the stimulation of cytokine production contributed to the elimination of the virus. In summary, the infection of resident alveolar macrophages with orthopoxviruses and the subsequent upregulation of chemokine expression attract several different leukocyte types, representing a critical event in antiviral defense.A highly attenuated orthopoxvirus strain, modified VACV Ankara (MVA), is being considered as a candidate for the production of a vaccine against smallpox and as a viral vector in gene therapeutic protocols (9). MVA, administered intranasally (i.n.) or intramuscularly as a short-term immunization, has been proven to be protective against a lethal challenge with the virulent VACV strain WR in a mouse model. In contrast, the VACV strain Elstree failed to protect mice when administered intramuscularly 48 h before challenge but was effective when the lethal challenge occurred 14 days postimmunization. Interestingly, an elevated concentration of various types of leukocytes, including monocytes, granulocytes, and T lymphocytes, was present in the lung 48 h after i.n. immunization with MVA (46). This respiratory immigration of leukocytes was most likely triggered by a chemoattractant factor produced by resident lung cells due to infection with MVA. In order to elucidate the mechanism underlying the migration of leukocytes, pilot experiments were performed to test whether MVA triggers the expression of a soluble factor capable of attracting leukocytes, especially monocytes.  相似文献   
143.
144.
Progressive pseudorheumatoid dysplasia (PPRD) is a genetic, non-inflammatory arthropathy caused by recessive loss of function mutations in WISP3 (Wnt1-inducible signaling pathway protein 3; MIM 603400), encoding for a signaling protein. The disease is clinically silent at birth and in infancy. It manifests between the age of 3 and 6 years with joint pain and progressive joint stiffness. Affected children are referred to pediatric rheumatologists and orthopedic surgeons; however, signs of inflammation are absent and anti-inflammatory treatment is of little help. Bony enlargement at the interphalangeal joints progresses leading to camptodactyly. Spine involvement develops in late childhood and adolescence leading to short trunk with thoracolumbar kyphosis. Adult height is usually below the 3rd percentile. Radiographic signs are relatively mild. Platyspondyly develops in late childhood and can be the first clue to the diagnosis. Enlargement of the phalangeal metaphyses develops subtly and is usually recognizable by 10 years. The femoral heads are large and the acetabulum forms a distinct "lip" overriding the femoral head. There is a progressive narrowing of all articular spaces as articular cartilage is lost. Medical management of PPRD remains symptomatic and relies on pain medication. Hip joint replacement surgery in early adulthood is effective in reducing pain and maintaining mobility and can be recommended. Subsequent knee joint replacement is a further option. Mutation analysis of WISP3 allowed the confirmation of the diagnosis in 63 out of 64 typical cases in our series. Intronic mutations in WISP3 leading to splicing aberrations can be detected only in cDNA from fibroblasts and therefore a skin biopsy is indicated when genomic analysis fails to reveal mutations in individuals with otherwise typical signs and symptoms. In spite of the first symptoms appearing in early childhood, the diagnosis of PPRD is most often made only in the second decade and affected children often receive unnecessary anti-inflammatory and immunosuppressive treatments. Increasing awareness of PPRD appears to be essential to allow for a timely diagnosis.  相似文献   
145.
Iron-deficiency anemia (IDA) is the most common nutritional deficiency in childhood throughout the world. Although it has been shown that IRA is associated with elevated plasma copper and depleted zinc levels in children, there are conflicting results on the effect of iron supplementation on the absorption of these elements. The aim of this study was to investigate the effects of ferrous and ferric iron supplementation on the trace element status in children (n=25, aged 8-168 mo) with IDA. Fourteen of them were treated with ferric hydroxide-polymaltose complex (Ferrum, Vifor, Switzerland) (6 mg/d in the first 3 mo for initial therapy and 3 mg/kg for 3 mo as maintenance); the others were treated with a ferrous sulfate complex (FerroSanol, Schwarz, Germany) (6 mg/d in the first 3 mo for initial therapy and 3 mg/kg for 3 mo as maintenance). Plasma copper, zinc, and ceruloplasmin levels as well as hematological parameters were determined at baseline and the first, third, and sixth month of the treatment period. The hemoglobin and iron levels of patients in both groups were higher in the first and sixth months compared to baseline. Although the ceruloplasmin levels were depleted (48.9 mg/dL vs 41.4 mg/dL, p=0.035) during ferrous iron treatment, the copper and zinc levels remained unchanged. On the other hand, ferric iron supplementation led to an increase in zinc levels in the sixth month of treatment (0.77 mg/L vs 1.0 mg/L, p=0.021). The plasma copper levels were lower in the ferrous iron-treated group at the end of the first month of treatment than in the ferric irontreated group (1.06 mg/L vs 1.29 mg/L, p=0.008). In conclusion, our data showed that copper and ceruloplasmin metabolisms were affected by ferrous iron supplementation, whereas ferric iron kept them to normal levels of zinc, possibly by affecting their absorption. We conclude that the copper and zinc status of patients with IDA should be taken into consideration before and after iron therapy.  相似文献   
146.
147.
OBJECTIVE: To evaluate the importance of fine needle aspiration cytology (FNAC) in the diagnosis of hepatocellular carcinoma (HCC). STUDY DESIGN: We analyzed 17 cytologic and 5 architectural features in a series of 320 FNACs from HCC and compared them with 73 FNACs from benign lesions and with 705 FNACs from metastatic carcinomas. One thousand ninety-eight patients who were diagnosed by liver FNAC between December 1988 and July 1998 and had adequate follow-up were included in the study. The specimens were evaluated according to the presence or absence of the cytologic features and cellular arrangement. A stepwise logistic regression analysis was performed on the data to determine the variables predictive of HCC. RESULTS: Multinucleated tumor giant cells, cytoplasmic hyaline and central sinusoidal pattern were selected as the 3 most predictive parameters for differentiated reactive hepatocytes from HCC (P < .0001), while bile, centrally located nucleus in an atypical cell and intranuclear inclusion were selected as the 3 most predictive parameters for differentiated metastatic carcinoma from HCC (P < .0001-< .001) by stepwise logistic regression analysis. CONCLUSION: In the 1,098 patients suspected of having hepatic malignancy, a correct diagnosis was made by a combination of the above features. The sensitivity of this procedure for hepatic malignancy was 99.5%, and the specificity was 100%.  相似文献   
148.
Dihydropyrimidine dehydrogenase (DPD, E.C. 1.3.1.2) was purified from sheep liver with a yield of 16.7%, purification fold of 407.5 and specific activity of 0.705?EU/mg proteins. The purification procedure consisted of ammonium sulphate fractionation, DEAE ion exchange chromatography and 2′,5′-ADP Sepharose-4B affinity chromatography. The molecular weight determined by SDS-PAGE and was found 111?kDa. Optimum pH, ionic strength temperature and stable pH were determined as 8.0, 0.9?mM, 50?°C and 6.0, respectively. The kinetic parameters (Km and Vmax) of the enzyme were determined with NADPH as 22.97?μM and 0.17?EU/mL, respectively. The same parameters were determined with uracil as 17.46?μM and 0.14?EU/mL, respectively. Additionally, in vitro inhibitory effects of some antidepressant drugs including escitalopram, fluoxetine, mirtazapine, haloperidol and some anaesthetic drugs including propofol and lidocaine were investigated against DPD. In addition, IC50 values for each active drug obtained for escitalopram, fluoxetine, mirtazapine, haloperidol, propofol and lidocaine were determined as 1736.11, 13.24, 86.65, 99.03, 0.21 and 15.07?μM, respectively.  相似文献   
149.
Two novel monomeric [C18H17Cl3N2O2Fe] (1) and dimeric [C38H36N4O4Cl6Fe2] (2) Fe(III) tetradentate Schiff base complexes have been synthesized and their crystal structures have been determined by single crystal X-ray diffraction analysis. In complex (1) the Schiff base ligand coordinates toward one iron atom in a tetradentate mode and each iron atom is five coordinated with the coordination geometry around iron atom which can be described as a distorted square pyramid. The presence of a short (2.89 Å) non-bonding interatomic Fe···O distances between adjacent monomeric Fe(III) complexes results in the formation of a dimer. Structural analysis of compound (2) shows that the structure is a centrosymmetric dimer in which the six coordinated Fe(III) atoms are linked by μ-phenoxo bridges from one of the phenolic oxygen atoms of each Schiff base ligand to the opposite metal center. The variable-temperature (2-300 K) magnetic susceptibility (χ) data of these two compounds have been investigated. The results show that for both complexes Fe(III) centers are in the high spin configuration (S = 5/2) and indicate antiferromagnetic spin-exchange interaction between Fe(III) ions. The obtained results are briefly discussed using magnetostructural correlations developed for other class of iron(III) complexes.  相似文献   
150.
 Fetal electrocortical activity (ECoG) is characterized by two distinct patterns: HVSA (high voltage, slow activity) and LVFA (low voltage, fast activity). Using the wavelet transform (WT), we recently reported that the frequency characteristics of these two ECoG patterns undergo significant maturational changes prior to birth (Akay et al. 1994a). We now report that fetal ECoG can also be significantly affected by pharmacological agents. In this paper, we compared the effects of two opioid drugs (morphine and [D-Pen2, D-Pen5]enkephalin, DPDPE) on fetal ECoG, using the chronically instrumented fetal lamb model. Morphine was infused intravenously (i.v.) at 2.5 mg/h, while DPDPE was infused into the lateral cerebroventricle (i.c.v.) at 30 μg/h. The ECoG was analyzed using WT. We performed multiresolution decomposition for four sets of parameters D 2 j where −1<j<−4. The four series WTs represent the detail signal bandwidths: (1) 16–32 Hz, (2) 8–16 Hz, (3) 4–8 Hz, (4) 2–4 Hz. The data were subjected to statistical analysis using the Kolmogorov–Smirnov (KS) test. Both morphine and DPDPE resulted in a significant increase in power in the first wavelet band, while power was reduced in the second, third and fourth wavelet bands. In addition, both drugs resulted in a disruption of the normal cyclic pattern between the two ECoG patterns. There was a difference in the time course of action between morphine and DPDPE. This is the first occasion in which continuous ECoG has been subjected to rigorous statistical analysis. The results suggest that the WT-KS method is most suitable for quantitating changes in the ECoG induced by pharmacological agents. Received: 21 January 1994/Accepted in revised form: 15 September 1994  相似文献   
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