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51.
Intracellular growth factors in polycythemia vera and other myeloproliferative disorders. 总被引:2,自引:1,他引:2 下载免费PDF全文
J Eid R F Ebert M S Gesell J L Spivak 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(2):532-536
In polycythemia vera, idiopathic myelofibrosis, and essential thrombocytosis, hematopoietic cell proliferation is increased in the absence of a recognizable stimulus, suggesting the autonomous production of growth factors in these disorders. Sonicates of peripheral blood mononuclear cells (PBMNC) from patients with polycythemia vera, idiopathic myelofibrosis, and essential thrombocytosis contained soluble factors that stimulated the proliferation of quiescent-confluent 3T3 cells. PBMNC sonicates from normal individuals; from patients with secondary erythrocytosis, chronic myelogenous leukemia, B-cell chronic lymphocytic leukemia, and acute myelogenous leukemia; and from K-562 and HL-60 cells did not stimulate proliferation. Polycythemia vera PBMNC sonicates also induced anchorage-independent colony formation in soft agar by normal rat kidney fibroblasts. Both the mitogenic and transforming activities of the polycythemia vera PBMNC sonicates resided in the T-lymphocyte-depleted mononuclear fraction of the PBMNC and were not secreted. By gel filtration, reversed-phase HPLC and NaDodSO4/PAGE, the mitogenic and transforming activities in the polycythemia vera PBMNC were localized to three proteins with molecular masses of 13-, 17-, and 65-kDa. The 13-kDa protein was only mitogenic, and the 17-kDa protein was only transforming, whereas the 65-kDa protein had both mitogenic and transforming activity. These proteins may be involved in the autonomous hematopoiesis that characterizes polycythemia vera, idiopathic myelofibrosis, and essential thrombocytosis. 相似文献
52.
Dani?lle Volker Moniek C Zijlstra-Vlasveld Johannes R Anema Aartjan TF Beekman Evelien PM Brouwers Wilco HM Emons A Gijsbert C van Lomwel Christina M van der Feltz-Cornelis 《Journal of medical Internet research》2015,17(5)
Background
Common mental disorders are strongly associated with long-term sickness absence, which has negative consequences for the individual employee’s quality of life and leads to substantial costs for society. It is important to focus on return to work (RTW) during treatment of sick-listed employees with common mental disorders. Factors such as self-efficacy and the intention to resume work despite having symptoms are important in the RTW process. We developed “E-health module embedded in Collaborative Occupational health care” (ECO) as a blended Web-based intervention with 2 parts: an eHealth module (Return@Work) for the employee aimed at changing cognitions of the employee regarding RTW and a decision aid via email supporting the occupational physician with advice regarding treatment and referral options based on monitoring the employee’s progress during treatment.Objective
This study evaluated the effect of a blended eHealth intervention (ECO) versus care as usual on time to RTW of sick-listed employees with common mental disorders.Methods
The study was a 2-armed cluster randomized controlled trial. Employees sick-listed between 4 and 26 weeks with common mental disorder symptoms were recruited by their occupational health service or employer. The employees were followed up to 12 months. The primary outcome measures were time to first RTW (partial or full) and time to full RTW. Secondary outcomes were response and remission of the common mental disorder symptoms (self-assessed).Results
A total of 220 employees were included: 131 participants were randomized to the ECO intervention and 89 to care as usual (CAU). The duration until first RTW differed significantly between the groups. The median duration was 77.0 (IQR 29.0-152.3) days in the CAU group and 50.0 (IQR 20.8-99.0) days in the ECO group (hazard ratio [HR] 1.390, 95% CI 1.034-1.870, P=.03). No significant difference was found for duration until full RTW. Treatment response of common mental disorder symptoms did not differ significantly between the groups, but at 9 months after baseline significantly more participants in the ECO group achieved remission than in the CAU group (OR 2.228, 95% CI 1.115-4.453, P=.02).Conclusions
The results of this study showed that in a group of sick-listed employees with common mental disorders, applying the blended eHealth ECO intervention led to faster first RTW and more remission of common mental disorder symptoms than CAU.Trial Registration
Netherlands Trial Register NTR2108; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2108. (Archived by WebCite at http://www.webcitation.org/6YBSnNx3P). 相似文献53.
54.
Nkiruka V. Arinze Sharon M. Karp Sabina B. Gesell 《Journal of immigrant and minority health / Center for Minority Public Health》2016,18(1):282-286
Excessive gestational weight gain (GWG) is associated with complications for both mother and child. Minority women are at increased risk for excessive GWG, yet are underrepresented in published weight control interventions. To inform future interventions, we examined the prevalence and accuracy of provider advice and its association with personal beliefs about necessary maternal weight gain among predominantly Latina pregnant women. Secondary analysis examining baseline data (N = 123) from a healthy lifestyle randomized controlled trial conducted in and urban area of the South East. Only 23.6 % of women reported being told how much weight to gain during pregnancy; although 58.6 % received advice that met Institute of Medicine recommendations. Concordance of mothers’ personal weight gain target with clinical recommendations varied by mothers’ pre-pregnancy weight status [χ (4) 2 = 9.781, p = 0.044]. Findings suggest the need for prenatal providers of low-income, minority women to engage patients in shaping healthy weight gain targets as a precursor to preventing excessive GWG and its complications. 相似文献
55.
J J Feldmeier H W Hopf R A Warriner C E Fife L B Gesell M Bennett 《Undersea & hyperbaric medicine》2005,32(3):157-168
A small body of literature has been published reporting the application of topical oxygen for chronic non-healing wounds . Frequently, and erroneously, this form of oxygen administration has been referred to as "topical hyperbaric oxygen therapy" or even more erroneously "hyperbaric oxygen therapy." The advocates of topical oxygen claim several advantages over systemic hyperbaric oxygen including decreased cost, increased safety, decreased complications and putative physiologic effects including decreased free radical formation and more efficient delivery of oxygen to the wound surface. With topical oxygen an airtight chamber or polyethylene bag is sealed around a limb or the trunk by either a constriction/tourniquet device or by tape and high flow (usually 10 liters per minute) oxygen is introduced into the bag and over the wound. Pressures just over 1.0 atmospheres absolute (atm abs) (typically 1.004 to 1.013 atm abs) are recommended because higher pressures could decrease arterial/capillary inflow. The premise for topical oxygen, the diffusion of oxygen into the wound adequate to enhance healing, is attractive (though not proven) and its delivery is certainly less complex and expensive than hyperbaric oxygen. When discussing the physiology of topical oxygen, its proponents frequently reference studies of systemic hyperbaric oxygen suggesting that mechanisms are equally applicable to both topical and systemic high pressure oxygen delivery. In fact, however, the two are very different. To date, mechanisms of action whereby topical oxygen might be effective have not been defined or substantiated. Conversely, cellular toxicities due to extended courses of topical oxygen have been reported, although, again these data are not conclusive, and no mechanism for toxicity has been examined scientifically. Generally, collagen production and fibroblast proliferation are considered evidence of improved healing, and these are both enhanced by hyperbaric oxygen therapy. Paradoxically, claims of decreased collagen production and fibroblast inhibition in wounds subjected to topical oxygen have been reported in studies of topical oxygen as a benefit of topical oxygen therapy. The literature on topical oxygen is mostly small case series or small controlled but not randomized trials. Moreover, the studies generally are not aimed at specific ulcer types, but rather at "chronic wounds." This non-specific approach is recognized as a major design flaw in any study of therapies designed to improve impaired wound healing. The only randomized trial for topical oxygen in diabetic foot ulcers actually showed a tendency toward impaired wound healing in the topical oxygen group. Contentions that topical oxygen is superior to hyperbaric oxygen are not proven. There are potentially plausible mechanisms that support both possibly beneficial and detrimental effects of topical oxygen therapy, and thus well designed and executed basic science research and clinical trials are clearly needed. There is some ongoing research in regard to the role of topical oxygen at established wound laboratories. Neither CMS nor other third party payors recognize or reimburse for topical oxygen. Therefore, the policy of the Undersea and Hyperbaric Medical Society in regard to topical oxygen is stated as follows: 1. Topical oxygen should not be termed hyperbaric oxygen since doing so either intentionally or unintentionally suggests that topical oxygen treatment is equivalent or even identical to hyperbaric oxygen. Published documents reporting experience with topical oxygen should clearly state that topical oxygen not hyperbaric oxygen is being employed. 2. Mechanisms of action or clinical study results for hyperbaric oxygen cannot and should not be co-opted to support topical oxygen since hyperbaric oxygen therapy and topical oxygen have different routes and probably efficiencies of entry into the wound and their physiology and biochemistry are necessarily different. 3. The application of topical oxygen cannot be recommended outside of a clinical trial at this time based on the volume and quality of scientific supporting evidence available, nor does the Society recommend third party payor reimbursement. 4. Before topical oxygen can be recommended as therapy for non-healing wounds, its application should be subjected to the same intense scientific scrutiny to which systemic hyperbaric oxygen has been held. 相似文献
56.
57.
FR Kaufman G Costin DW Thomas FR Sinatra TF Roe HB Neustein 《Archives of disease in childhood》1984,59(8):787-789
The diagnosis of optic nerve hypoplasia and hypopituitarism must be entertained in infants who present for evaluation of cholestatic jaundice, particularly if there is associated hypoglycaemia and wandering nystagmus. Although the hepatic dysfunction seems to resolve, the long term prognosis of liver disease in optic nerve hypoplasia remains unknown. 相似文献
58.
Tobi M Kaila V Hassan N Gallinger S Fligiel S Hatfield J Gesell M Sakr W Luk G Odze RD 《Human pathology》1999,30(4):467-473
Unlike colorectal cancer, risk markers for adenocarcinoma of the small intestine (ASI) have not been identified. Because the demographic and pathological features of both of these diseases are similar, immunohistochemistry was performed using monoclonal antibodies for three colonic premalignant markers, Adnab-9 (recognizes a colonic adenoma epitope), CaCo3/61, and FBB2/29 (small intestine proteoglycans expressed ectopically in colonic neoplasms), in normal and neoplastic small intestinal epithelium, and the results were compared with normal controls. Adnab-9 was also examined in 20 familial adenomatous polyposis (FAP) patients, a population known to be at an increased risk for ASI. Immunohistochemistry in normal and neoplastic tissue (adenoma, adenocarcinoma) from 18 patients with primary adenocarcinoma of the small intestine was compared with normal small intestine from 10 nonneoplastic controls. Four of 10 (40%) cases of normal small intestinal epithelium from controls were mildly positive in less than 10% of crypts, versus strong staining (>50% of crypts) in 16 of 18 (89%) patients with adenocarcinoma, and in 17 of 20 (85%) patients with FAP (P<.05). Adnab-9 predominantly stained Paneth cells as well as rare crypt and basal villous goblet cells. Adenomatous epithelium from the adenocarcinoma cases and adenomas from the FAP patients showed staining of Adnab-9 in 63% and 78% of cases, respectively. Only 17% of adenocarcinomas were positive for Adnab-9. In contrast, neither CaCo3/61 nor FBB2/29 showed any significant differences in the degree of staining in normal small intestinal epithelium in patients with adenocarcinoma compared with controls. Enhanced Adnab-9 staining in normal small intestinal epithelium from patients who harbor adenocarcinoma, and in FAP patients, supports its role as a risk marker of small intestinal neoplasia. 相似文献
59.
We report the case of an 8 week old infant with fulminant autoimmune haemolytic anaemia refractory to conventional immunomodulating treatment. Massive haemolysis resulted in cardiac decompensation and acute renal failure which necessitated mechanical ventilation and peritoneal dialysis. Rituximab, a chimeric anti-CD20 monoclonal antibody, halted progression of the haemolytic process, but the patient died of acute viral pneumonia and disseminated fungal infection. Earlier introduction of rituximab might have prevented the renal complications. Paediatricians should be aware of this useful therapeutic tool for treatment of refractory autoimmune haemolytic anaemia and balance its use against the risk of potential life threatening infection. 相似文献
60.
Like in the polymorphonuclear leukocyte (PMN), the platelet-derived growth factor (PDGF) purified to homogeneity is capable of inducing monocyte activation responses as evaluated by generation of superoxide anion (O-.2) from membrane-associated oxidase system, release of granule enzymes, and enhanced cell adherence and cell aggregation. Superoxide anion release was maximized at 10 ng/mL PDGF and was comparable to that induced by 10(-7) mol/L formyl-methionyl-leucyl- phenylalanine. The potency of PDGF to induce this response in monocytes was of the same magnitude as that observed in PMNs. Similarly, lysozyme release and monocyte adherence were also increased in a dose-dependent manner and achieved maximal responses at 40 ng/mL concentration of PDGF. The PDGF concentration required to achieve maximal monocyte aggregation was two-fold (60 ng/mL) of that found for PMNs. In contrast to PMNs, a positive correlation (gamma = .93; P less than .01) was observed between the increases of PDGF concentration and beta- glucuronidase release. These findings indicate that PDGF can induce the full sequence of cell activation events in human monocytes similar to human PMNs. 相似文献