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21.
Retinopathy of prematurity (ROP) is a vasoproliferative disorder that occurs in premature infants and may lead to permanent visual impairment. We investigated both the possible protective role of N-acetyl cysteine (NAC) for preventing ROP and the role of IGF-1 in the disorder. Forty-five newborn rats were divided into three groups. Group 1 was raised in room air as controls. Group 2 was exposed to 60% oxygen for 14 days after birth, then transferred to room air. Group 3 was exposed to the same conditions as group 2, but received intraperitoneal injections of NAC on postnatal days 7–17. After 35 days, both eyes of all rats were processed for histology. Some sections were stained with hematoxylin and eosin to assess structural changes and other sections were immunostained to determine the location of IGF-1. Frozen sections also were prepared and stained for adenosine triphosphatase to detect retinal blood vessels. Compared to the controls, more blood vessels, many of which were abnormal, and increased IGF-1 expression were observed in group 2. In group 3, abnormal blood vessels and IGF-1 expression were less evident. NAC appeared to be an effective vascular-protective agent for ROP by decreasing IGF-1 expression. 相似文献
22.
Teng YK Verburg RJ Verpoort KN Diepenhorst GM Bajema IM van Tol MJ Jol-van der Zijde EC Toes RE Huizinga TW van Laar JM 《Arthritis research & therapy》2007,9(5):R106
In order to identify pathogenic correlates of refractory rheumatoid arthritis (RA), antibodies against anti-cyclic citrullinated
protein (ACPAs) were investigated in RA patients in whom the dysregulated immune system had been ablated by high-dose chemotherapy
(HDC) and autologous haematopoietic stem cell transplantation (HSCT). Six patients with refractory RA were extensively characterized
in terms of levels of total immunoglobulins, RA-specific autoantibodies (ACPAs and rheumatoid factor) and antibodies against
rubella, tetanus toxoid (TT) and phosphorylcholine before and after HDC plus HSCT. Additionally, the avidity of ACPAs was
measured before and after treatment and compared with the avidity of TT antibodies following repeated immunizations. Synovial
biopsies were obtained by arthroscopy before HDC plus HSCT, and analyzed by immunohistochemistry. In the three patients with
clinically long-lasting responses to HDC plus HSCT (median 423 days), significant reductions in ACPA-IgG levels after therapy
were observed (median level dropped from 215 to 34 arbitrary units/ml; P = 0.05). In contrast, stable ACPA-IgG levels were observed in three patients who relapsed shortly after HDC plus HSCT (median
of 67 days). Clinical responders had ACPA-IgG of lower avidity (r = 0.75; P = 0.08) and higher degree of inflammation histologically (r = 0.73; P = 0.09). Relapse (after 38 to 530 days) in all patients was preceded by rising levels of low avidity ACPA-IgG (after 30 to
388 days), in contrast to the stable titres of high avidity TT antibodies. In conclusion, humoral autoimmune responses were
differentially modulated by immunoablative therapy in patients with synovial inflammation and low avidity ACPA-IgG autoantibodies
as compared with patients with high levels of high avidity ACPA-IgG. The distinct clinical disease course after immunoablative
therapy based on levels and avidity of ACPA-IgG indicates that refractory RA is not a single disease entity. 相似文献
23.
EM Tazi I Lalya MF Tazi Y Ahellal H M'rabti H Errihani 《World journal of surgical oncology》2010,8(1):1-3
Goblet cell carcinoid of the large intestine is a rare neoplasm, usually located in ascending colon and rectum. A 60-year-old male patient underwent surgery after the diagnosis of acute abdomen. Exploratory laparotomy revealed perforation with a diameter of 1 cm at the site of the previously performed gastroenterostomy and dilatation of the right colic flexure, secondary to a solid obstructive mass located in the mid-portion of transverse colon. Histopathological investigation of the biopsies, taken from the gastroenterostomy site and the tumor, revealed mixed carcinoid-adenocarcinoma with carcinoid component, predominantly composed of goblet cells. Three cycles of FOLFOX-4 protocol was administered. Following respiratory distress secondary to pulmonary metastasis, the patient's condition deteriorated and subsequently died in the fourth postoperative month. Our aim with this paper is to point out that more cases should be reported for more effective diagnosis, histopathological study, clinical investigation, treatment and prognosis of this specific neoplasm. 相似文献
24.
Irene EM Bultink 《Arthritis research & therapy》2010,12(1):107
Cardiovascular disease (CVD) has been identified as a major contributor to morbidity and mortality in patients with systemic
lupus erythematosus (SLE). The etiology of premature CVD in SLE is supposed to have many factors, including traditional coronary
artery disease (CAD) risk factors, antiphospholipid antibodies, and metabolic and inflammatory factors. Despite the overwhelming
interest in CVD in SLE research, prospective studies evaluating risk factors for hard endpoints (that is, cardiovascular events)
are relatively scarce. The article by Gustafsson and colleagues suggests that prothrombotic factors play an important role
in SLE-related CVD and that the influence of traditional CAD risk factors might be limited. 相似文献
25.
Formation of new blood vessels, which is fundamental in embryonic development, occurs through a combination of angiogenesis and vasculogenesis. Angiogenesis also plays a vital role postnatally, especially in reparative processes such as wound and fracture healing. Some of these events, especially in fracture healing, recapitulate processes observed in developmental angiogenesis. However, dysregulated angiogenesis is well documented to underlie a number of pathological disorders, including rheumatoid arthritis (RA). The vascular endothelial growth factor (VEGF)/VEGF receptor system is the best characterized regulator of angiogenesis. VEGF is expressed in a range of cells in response to soluble mediators (such as cytokines and growth factors), cell-bound stimuli (such as CD40 ligand), and environmental factors (such as hypoxia). As a consequence, this molecule is vital in the modulation of physiological and pathological angiogenesis. This review will focus in particular on the role played by VEGF in embryogenesis and skeletal growth, in fracture healing (in which increased angiogenesis is likely to be beneficial in promoting union), and in RA (in which excessive angiogenesis is thought to play a significant role in disease pathogenesis). In the not-too-distant future, targeting VEGF may prove to be of benefit in the treatment of diseases associated with excessive or aberrant angiogenesis, such as malignancies and RA. 相似文献
26.
Polygalacturonase inhibiting protein (PGIP) is localized in plant cell walls and plays an important role both in pectic substance metabolism and in prevention of the penetration of phytopathogenic microorganisms. Apparently, PGIP is responsible for the specificity of cell--cell interactions during pollination or inoculation by fungi nonpathogenic for the particular plant. PGIPs from different plants share a basic common structure. They are rather thermostable glycoproteins enriched with leucine and contain about 20% carbohydrates; the molecular weight varies between 37-54 kD. The synthesis of PGIP is encoded by one gene, and its expression is stimulated by injury and fungal infection. The resistance of plant tissues to infection frequently correlates with PGIP expression and with inhibiting action on fungal PG. Thus, PGIP is believed to be useful for gene engineering to obtain transgenic plants resistant to fungal infection or retaining commercial value during storage. 相似文献
27.
Antibodies to citrullinated proteins and differences in clinical progression of rheumatoid arthritis
van der Helm-van Mil AH Verpoort KN Breedveld FC Toes RE Huizinga TW 《Arthritis research & therapy》2005,7(5):R949-R958
Antibodies to citrullinated proteins (anti-cyclic-citrullinated peptide [anti-CCP] antibodies) are highly specific for rheumatoid
arthritis (RA) and precede the onset of disease symptoms, indicating a pathogenetic role for these antibodies in RA. We recently
showed that distinct genetic risk factors are associated with either anti-CCP-positive disease or anti-CCP-negative disease.
These data are important as they indicate that distinct pathogenic mechanisms are underlying anti-CCP-positive disease or
anti-CCP-negative disease. Likewise, these observations raise the question of whether anti-CCP-positive RA and anti-CCP-negative
RA are clinically different disease entities. We therefore investigated whether RA patients with anti-CCP antibodies have
a different clinical presentation and disease course compared with patients without these autoantibodies. In a cohort of 454
incident patients with RA, 228 patients were anti-CCP-positive and 226 patients were anti-CCP-negative. The early symptoms,
tender and swollen joint count, and C-reactive protein level at inclusion, as well as the swollen joint count and radiological
destruction during 4 years of follow-up, were compared for the two groups. There were no differences in morning stiffness,
type, location and distribution of early symptoms, patients' rated disease activity and C-reactive protein at inclusion between
RA patients with and without anti-CCP antibodies. The mean tender and swollen joint count for the different joints at inclusion
was similar. At follow-up, patients with anti-CCP antibodies had more swollen joints and more severe radiological destruction.
Nevertheless, the distribution of affected joints, for swelling, bone erosions and joint space narrowing, was similar. In
conclusion, the phenotype of RA patients with or without anti-CCP antibodies is similar with respect to clinical presentation
but differs with respect to disease course. 相似文献
28.
Background
In crossbreeding programs, genomic selection offers the opportunity to make efficient use of information on crossbred (CB) individuals in the selection of purebred (PB) candidates. In such programs, reference populations often contain genotyped PB animals, although the breeding objective is usually more focused on CB performance. The question is what would be the benefit of including a larger proportion of CB individuals in the reference population.Methods
In a deterministic simulation study, we evaluated the benefit of including various proportions of CB animals in a reference population for genomic selection of PB animals in a crossbreeding program. We used a pig breeding scheme with selection for a moderately heritable trait and a size of 6000 for the reference population.Results
Applying genomic selection to improve the performance of CB individuals, with a genetic correlation between PB and CB performance (rPC) of 0.7, selection accuracy of PB candidates increased from 0.49 to 0.52 if the reference population consisted of PB individuals, it increased to 0.55 if the reference population consisted of the same number of CB individuals, and to 0.60 if the size of the CB reference population was twice that of the reference population for each PB line. The advantage of using CB rather than PB individuals increased linearly with the proportion of CB individuals in the reference population. This advantage disappeared quickly if rPC was higher or if the breeding objective put some emphasis on PB performance. The benefit of adding CB individuals to an existing PB reference population was limited for high rPC.Conclusions
Using CB rather than PB individuals in a reference population for genomic selection can provide substantial advantages, but only when correlations between PB and CB performances are not high and PB performance is not part of the breeding objective. 相似文献29.
Grzegorz Borsuk Aneta Strachecka Krzysztof Olszewski Jerzy Paleolog Jacek Chobotow Marcin Anusiewicz 《Biologia》2013,68(3):533-538
During many insemination interventions semen coagulates already within the insemination needle, which considerably lengthens the duration of inseminating a single queen bee. Considering this, the authors decided to determine the type and activity of proteases and their inhibitors in normal and coagulated sperm. The samples were collected from mature and old drones. The sperm proteins were isolated in 1% Triton X-100. The samples containing isolated proteins were tested as follows: protein concentration assay by the Lowry method; proteolytic activity in relation to various substrates (gelatine, haemoglobin, ovoalbumin, albumin, cytochrome C, casein) by the modified Anson method; proteolytic activity in relation to diagnostic inhibitors of proteolytic enzymes (pepstatin A, PMSF, iodoacetamide, o-phenantrolin), using the Lee & Lin method; acidic, neutral and basic protease activity by means of the modified Anson method; electrophoretic analysis of proteins in a polyacrylamide gel for protease detection with the Laemmli method; the activity of aspartic and serine protease inhibitors by the Lee and Lin method; electrophoretic analysis of proteins in a polyacrylamide gel for protease inhibitor activity detection by means of the modified Felicioli method. The mixing of non-coagulated semen from different drones increased protein concentration. The activities of proteases were decreased in normal sperm samples as compared with a corresponding rise in the sperm mixture from many drones. The non-coagulated sperm samples were found to contain aspartic and serine proteases. Additionally, thiolic and metallic proteases were also found in the coagulated sperm samples. There was a rise in protease inhibitor activity at pH 3.0 and 12.0, and a fall at pH 7.0 after mixing the sperm samples collected from numerous drones. Oscillation in these activities stemmed from sperm coagulation. 相似文献
30.
Helene Larsen Barbara Muz Tak L Khong Marc Feldmann Ewa M Paleolog 《Arthritis research & therapy》2012,14(4):1-18