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91.
Objective: To ascertain blood lead levels in a sample of preschool children from Fremantle, Western Australia, and to correlate these with possible risk factors.
Methodology The study was a cross-sectional prevalence survey of 120 children from day-care centres and 44 hospital inpatients. Blood lead and ferritin levels were determined and a risk factor questionnaire was completed by parents.
Results Of the 164 children 25.6% had lead levels above the NH&MRC goal (<10μg/dL). Nine of 133 (6.7%) had ferritin levels below 10 μg/L suggesting iron deficiency. Excessive blood lead concentrations as defined by the NH&MRC (>9μg/dL) related to: child's presence during house renovation (OR 3.35, P = 0.007, 95% Cl 1.39-8.81); Aboriginality (OR 6.4, P = 0.008, 95% Cl 1.6-24.9), and, in the 9-24 month age group, inversely to distance between home and a road carrying >7000 vehicles/day (r-0.56, P = 0.009, n = 24).
Conclusions A group of Fremantle children with unacceptably high blood lead levels has been identified. Renovation of older housing and Aboriginality are important risk factors. 相似文献
Methodology The study was a cross-sectional prevalence survey of 120 children from day-care centres and 44 hospital inpatients. Blood lead and ferritin levels were determined and a risk factor questionnaire was completed by parents.
Results Of the 164 children 25.6% had lead levels above the NH&MRC goal (<10μg/dL). Nine of 133 (6.7%) had ferritin levels below 10 μg/L suggesting iron deficiency. Excessive blood lead concentrations as defined by the NH&MRC (>9μg/dL) related to: child's presence during house renovation (OR 3.35, P = 0.007, 95% Cl 1.39-8.81); Aboriginality (OR 6.4, P = 0.008, 95% Cl 1.6-24.9), and, in the 9-24 month age group, inversely to distance between home and a road carrying >7000 vehicles/day (r-0.56, P = 0.009, n = 24).
Conclusions A group of Fremantle children with unacceptably high blood lead levels has been identified. Renovation of older housing and Aboriginality are important risk factors. 相似文献
92.
93.
Ayala Espinosa MJ Pérez-Santonja JJ Alió Y Sanz JL Artola Roig A Cardona Ausina C 《Archivos de la Sociedad Espa?ola de Oftalmología》2000,75(12):835-837
CASE REPORT: We present a case of traumatic displacement of corneal flap in the superior temporal quadrant 13 days after LASIK. The flap was repositioned after gentle irrigation of BSS, cleaned the interface and then drying the flap to verify its stability. In the next day the flap was adhered, clear cornea,smooth and visual acuity without correction was 1.00. DISCUSSION: We should try immediately to reposition the flap after traumatic displacement, as in this case. 相似文献
94.
Peterson TC Peterson MR Robertson HA During M Dragunow M 《Molecular pharmacology》2002,61(6):1476-1488
Platelet-derived growth factor (PDGF) signals through several pathways, including mitogen-activated protein (MAP) kinase, Jun kinase, and C kinase, and stimulates proliferation of fibroblasts. Pentoxifylline inhibits PDGF-driven proliferation of fibroblasts. We have reported that pentoxifylline did not inhibit binding of PDGF to its specific cell-surface receptors or PDGF receptor phosphorylation. In this study, we investigated the effect of PDGF on the expression of c-fos and c-jun, because c-fos and c-jun form activator protein-1 complexes that stimulate genes involved in proliferation. We determined whether pentoxifylline would alter the expression of c-fos and c-jun. Our results indicate that PDGF induced the expression of both c-fos and c-jun. Pentoxifylline effectively reduced c-jun gene expression, which had been up-regulated by PDGF, but did not alter c-fos gene expression. The lack of effect on c-fos supports other studies from this laboratory, which indicate that pentoxifylline did not inhibit PDGF activation of MAP kinase. Treatment of fibroblasts with a phosphothioate c-jun antisense oligodeoxynucleotide reduced the levels of c-Jun protein and blocked PDGF-stimulated proliferation, suggesting a critical role for c-jun in PDGF-mediated proliferation. Combination of pentoxifylline and c-jun antisense suggested that they were likely inhibiting PDGF-stimulated proliferation at a single site in the PDGF signaling pathway. These results suggest that pentoxifylline inhibits PDGF-stimulated proliferation by selectively decreasing c-jun expression. To further define the mechanism of action of pentoxifylline, we assessed the effect of pentoxifylline on c-Jun and phosphorylated c-Jun immunoreactivity in cells treated with PDGF and cells that were transfected with wild-type c-jun plasmid using immunocytochemistry and Western blot analyses, and our results indicate that pentoxifylline inhibited phosphorylation of c-Jun on serine 73. 相似文献
95.
96.
Structural and functional neuroprotection in a rat model of Huntington's disease by viral gene transfer of GDNF 总被引:4,自引:0,他引:4
McBride JL During MJ Wuu J Chen EY Leurgans SE Kordower JH 《Experimental neurology》2003,181(2):213-223
Huntington's disease (HD) is an autosomal dominant disorder caused by an expanded polyglutamine (CAG) tract at the IT15 locus on chromosome 4. These excessive repeats lead to the degeneration of striatal and cortical neurons resulting in a devastating cognitive, psychiatric, and motor disorder for which no treatments are available. Neurotrophic factors support the viability of striatal neurons suggesting that they might prevent the inevitable neural degeneration and its accompanying functional decline associated with HD. The present study investigated whether glial cell line-derived neurotrophic factor (GDNF) delivered by an adeno associated virus could provide structural and functional neuroprotection in a rat model of HD. Lewis rats received bilateral injections of either AAV-GDNF (n = 12) or AAV-green fluorescence protein (AAV-GFP, n = 12) into the striatum followed 2 weeks later by chronic subcutaneous infusions of the mitochondrial toxin, 3-nitropropionic acid (3-NP, 38 mg/kg). All rats underwent 4 weeks of behavioral testing and were then sacrificed. Following 3-NP, the performance by AAV-GFP-treated rats on a raised platform motor task deteriorated while the performance by AAV-GDNF-treated rats was near normal (P < 0.001). AAV-GDNF-treated rats also received better scores on a blinded semi-quantitative neurological scale compared to rats receiving AAV-GFP (P < 0.001). Histological analyses supported our behavioral findings. 3-NP-treated rats receiving AAV-GDNF displayed 70% more NeuN-immunoreactive neurons compared to 3-NP-treated rats receiving AAV-GFP (P = 0.002). Similar findings were seen with dopamine-and-adenosine-3'5'-monophosphate-regulated phosphoprotein (DARPP-32) staining. These data indicate that the viral-mediated gene transfer of GDNF into the striatum provides neuroanatomical and behavioral protection in a rodent model of HD. 相似文献
97.
98.
MJ Veness F Foroudi V Gebski I Timms Y Sathiyaseelan B Cakir KW Tiver 《Journal of Medical Imaging and Radiation Oncology》2006,50(5):468-474
Radiation‐induced mucositis is an acute reaction of the mucosa of patients undergoing head and neck radiotherapy. It can have debilitating and dose‐limiting consequences. There is no consensus on an accepted intervention that significantly reduces its severity. Misoprostol is a synthetic prostaglandin E1 analogue, with properties of a mucosal cytoprotectant. We designed a randomized, double‐blind, placebo‐controlled trial of misoprostol in patients with head and neck cancer. The aim of this study was to determine if topical misoprostol was effective in reducing the severity of radiation‐induced mucositis in patients receiving radical dose radiotherapy. The effect of this intervention on a patient’s general well‐being was also investigated. The primary end‐point of the study was the incidence of Radiation Therapy Oncology Group grade 3 mucositis. Between 1999 and 2002, 83 patients were recruited into the study at Westmead and Nepean Hospitals, Sydney. Forty‐two patients were randomized to receive misoprostol and 41 to receive a placebo. Most patients received radiotherapy in the adjuvant setting (52 of the 83) and had either an oral cavity (42 of the 83) or an oropharyngeal (16 of the 83) cancer. We could not identify any significant difference in the incidence of severe mucositis based on whether patients were allocated to receive misoprostol or placebo. There was no significant difference in the mean area under the mucositis curve (13.2 vs 16.6; P = 0.1). Patients allocated to misoprostol did report slightly increased soreness (7.6 vs 6.9; P = 0.04) and a greater use of analgesics. However, this difference did not translate into a worse feeling of general well‐being as measured by a simple visual analogue scale (5.8 vs 5.2; P = 0.3). In conclusion, we were unable to identify a reduction in radiation‐induced mucositis in patients receiving misoprostol. There is a paucity of high‐level evidence on potentially useful interventions and a continued need for new and innovative research, incorporating quality‐of‐life measurements, in patients experiencing radiation‐induced mucositis. 相似文献
99.
GM Thambugala A Mohamed GFA O Neill MJ Fulham 《Journal of Medical Imaging and Radiation Oncology》2006,50(6):604-606
We present the FDG PET‐CT findings in a patient with persistent pain 7 weeks after a nephrectomy and lymph node dissection for a sarcomatoid renal cell carcinoma. Although conventional imaging was unable to detect evidence of metastatic spread outside the para‐aortic nodes, a PET‐CT scan showed unexpected extensive dissemination. Currently, there are no reports in the literature of the PET‐CT findings in sarcomatoid renal cell carcinomas. 相似文献
100.
A striking difference between two structurally related anti-estrogen
medicines is that tamoxifen is strongly hepatocarcinogenic in the rat,
whereas toremifene lacks such activity. To study the basis for this
difference, the initiating potential of tamoxifen and toremifene were
studied by measurement of rapid induction of hepatocellular altered foci
(HAF) that express placental-type glutathione S-transferase in the livers
of female Sprague-Dawley (S-D) rats and female Fischer 344 (F344) rats.
Both agents were administered by gavage at equimolar doses up to a dose
that produced marked weight gain suppression. In rats given the high dose
of 40 mg/kg per day tamoxifen continuously for 36 weeks, 75% of S-D rats
developed liver neoplasms, in contrast to only 10% of F344 rats. In the S-D
strain, tamoxifen produced a tendency to increased HAF at 2 weeks at the
dose of 40 mg/kg per day and by 12 weeks, a dose-related increase was
evident. In contrast, toremifene induced no HAF even at the equimolar high
dose of 42.4 mg/kg per day for 12 weeks. The induction of HAF by tamoxifen
was less in the F344 rats. Neither agent elicited increases in
hepatocellular proliferation in S-D or F344 rats. When phenobarbital was
administered for 24 weeks as a promoting agent after the anti-estrogens,
S-D rats given tamoxifen at 20 mg/kg per day for 12 weeks, developed liver
neoplasms, but not F344 rats or rats of either strain given even a higher
dose (42.4 mg/kg) of toremifene. Thus, tamoxifen has initiating activity in
these rat strains whereas toremifene does not.
相似文献