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481.
Photodynamic ablation of early cancers of the stomach by means of
mTHPC and laser irradiation: preliminary clinical experience 总被引:5,自引:1,他引:5 下载免费PDF全文
Background—Radical surgicaltreatment has been the first choice for early gastric cancer, but highresolution endosonography allows in situ diagnosis with a highsensitivity and specifity and in consequence the option of localendoscopic treatment.
Aims—To evaluate photodynamictherapy (PDT) usingmeso-tetrahydroxyphenylchlorin (mTHPC)as the photosensitiser in superficial gastric cancer.
Methods—Twenty two patients withsuperficial early gastric cancer received mTHPC (0.075 mg/kgintravenously) and were treated 96 hours later with red light at 652 nm(20 J/cm2). Tumour response was assessed by endoscopy andextensive biopsy.
Results—Endoscopies performed twoto three days after PDT showed a haemorrhagic fibrinoid necrosis of themucosal layer. Complete remission was achieved in 16/22 (73%)patients: 13/16 (80%) with intestinal type cancer and 3/6 (50%) witha diffuse Lauren's carcinoma. The mean follow up period was 12 monthsand 20 months, respectively. An average of 1.8 treatment sessions wasrequired. Severe side effects were not observed. Seven patients hadmild to moderate skin photosensivity reactions; 12 had local pain afterPDT for 1-10 days.
Conclusion—PDT using mTHPC as thephotosensitiser represents a safe and efficient method for topicaltreatment of early gastric cancer, especially of Lauren's intestinalcarcinoma. If the preliminary results can be verified in larger patientseries and during long term follow up, local treatment of early cancersof the stomach by PDT could be considered as a therapeutic option forselected patients.
Aims—To evaluate photodynamictherapy (PDT) usingmeso-tetrahydroxyphenylchlorin (mTHPC)as the photosensitiser in superficial gastric cancer.
Methods—Twenty two patients withsuperficial early gastric cancer received mTHPC (0.075 mg/kgintravenously) and were treated 96 hours later with red light at 652 nm(20 J/cm2). Tumour response was assessed by endoscopy andextensive biopsy.
Results—Endoscopies performed twoto three days after PDT showed a haemorrhagic fibrinoid necrosis of themucosal layer. Complete remission was achieved in 16/22 (73%)patients: 13/16 (80%) with intestinal type cancer and 3/6 (50%) witha diffuse Lauren's carcinoma. The mean follow up period was 12 monthsand 20 months, respectively. An average of 1.8 treatment sessions wasrequired. Severe side effects were not observed. Seven patients hadmild to moderate skin photosensivity reactions; 12 had local pain afterPDT for 1-10 days.
Conclusion—PDT using mTHPC as thephotosensitiser represents a safe and efficient method for topicaltreatment of early gastric cancer, especially of Lauren's intestinalcarcinoma. If the preliminary results can be verified in larger patientseries and during long term follow up, local treatment of early cancersof the stomach by PDT could be considered as a therapeutic option forselected patients.
Keywords:photodynamic therapy; early gastric cancer; localendoscopic therapy
相似文献482.
Ferris EJ; Ledor K; ben-Avi DD; Baker ML; Robbins KV; McCowan TC; Sharma B 《Radiology》1985,157(2):319-322
The cardiovascular applications of flexible fiber-optic technology are imminent because of recent advances in miniaturization. In the work described here, angioscopy, or vascular endoscopy, was performed in the cadaveric aorta and in the systemic and pulmonary circulations of the canine model and selected human patients. Subsequent to our development of percutaneous techniques, clinical trials have ranged from lower-extremity venoscopy to aortic-root arterioscopy. Angioscopy could be clinically useful because of relative or absolute contraindications to iodinated contrast material. The ability to see in color and three dimensions may afford some other advantages to angioscopy over conventional angiography. 相似文献
483.
Antimicrobial and antispasmodic activity of leaf extract and fractions of Stachytarpheta cayennensis
TC Okoye PA Akah CO Okoli AC Ezike FN Mbaoji 《Asian Pacific journal of tropical medicine》2010,3(3):189-192
ObjectiveTo investigate the antimicrobial activity of the methanol leaf extract (ME), n-hexane fraction (HF), ethylacetate fraction (EF) and methanol fraction (MF), of Stachytarpheta cayennensis C. Rich (verbenaceae) as well as to ascertain the antispasmodic effects of the ME and the various fractions (HF, EF and MF) on acetylcholine (Ach) and histamine (H) induced contractions on isolated guinea pig ileum.MethodsThe in vitro agar well diffusion method was used for the antimicrobial studies while the isolated tissue method was employed for the antispasmodic test. Organisms used were all clinical isolates of Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella paratyphi, Candida albicans and Aspergillus niger.ResultsThe extract and fractions exhibited dose dependent inhibition against all the bacteria tested and also exhibited insignificant antifungal activity against Candida albicans and Aspergillus niger. The minimum inhibitory concentration (MIC) of the extract and fractions (mg/mL) on Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella paratyphi respectively were ME 5.62, 14.12, 22.38, 2.11; EF 1.25, 6.30, 9.40, 9.40 and MF 3.98, 8.81, 39.80, 21.13. The n-hexane fraction exhibited MIC of 1.07 mg/mL against only Bacillus subtilis. The extract and fractions exhibited significant (P< 0.05) dose dependent attenuation of contractions induced by acetylcholine and histamine on isolated guinea pig ileum. Concentrations of the extract and fractions (μg/mL) which evoked 50% inhibition of maximal response exhibited by Ach were ME 0.64, HF 0.16, EF 0.08 and MF 0.15, while that of histamine included ME 5.12, HF 0.16, EF 0.04 and MF 0.64. Preliminary phytochemical studies on the extract and fractions indicated the presence of carbohydrates, alkaloids, saponins, flavonoids, steroids and terpenoids.ConclusionsThe extract and fractions of Stachytarpheta cayennensis possessed both antibacterial and antispasmodic effects confirming the claimed use in folkloric medicine for wound healing and gastrointestinal ulceration. 相似文献
484.
目的 建立并应用人巨细胞病毒 (HCMV)行列探针检测 (LiPA)技术 ,快速检测心肺移植患者HCMV耐更昔洛韦 (GCV)基因突变。方法 以HCMV UL97基因为靶序列 ,设计 13条特异性寡核苷酸探针 ,用Nested PCR扩增目的基因 ,LiPA技术检测与耐药有关的碱基突变。并对Nested PCR产物平行做直接序列测定 ,与LiPA结果比较。结果 16例心肺移植患者 ,LiPA技术检测发现 4例患者存在HCMV UL97基因突变 ,突变分别发生在编码子 5 2 0 ,5 95及 6 0 3,与直接序列测定比较 ,两者完全吻合。结论 长期应用GCV预防及治疗HCMV感染可以诱导病毒耐药 ,LiPA技术可作为检测HCMV基因突变的一种有效手段。 相似文献
485.
P. Gonschior C. Vogel-Wiens A. E. Goetz T. Y. Huehns F. Breger F. Gerheuser M. Fleuchaus U. Welsch R. Sroka M. Dellian H. A. Lehr B. Höfling 《Basic research in cardiology》1997,92(5):310-319
Background The effectiveness of local endovascular photodynamic therapy (PDT) in preventing tissue hyperplasia was evaluated in a vascular injury model.Methods Standardized unidirectional arterial injury with a directional atherectomy catheter was performed in porcine arteries (n=180). Animals (n=72) were randomly allocated to unidirectional injury only (Group 1), injury followed by drug delivery of photosensitizer with a porous balloon (Group 2), or by local exposure to monochromatic light (Group 3). In Group 4, injury was followed by local drug delivery of photosensitizer and subsequent exposure to light (PDT). Up to 21 days after treatment, all experimental vessels were excised, fixed and processed for histology, immunohistochemistry and transmission electron microscopy.Results After vascular injury an inflammatory and myoproliferative response was observed in Groups 1, 2 and 3 (mean tissue hyperplasia/media ratio 1.0±0.5 at 21 days; area tissue hyperplasia: 1.57±0.9 mm2). Proliferation in injured vascular segments (Group 1–3) reached a maximum at 7 days, with 6%. Only in Group 4, injury followed by photodynamic therapy, was there no significant vascular response (mean tissue hyperplasia/media ratio 0.3±0.2; area tissue hyperplasia: 0.1±0.05 mm2 p<0.001, proliferating cells 0.3%).Conclusion Vascular response after unidirectional injury was suppressed only by endovascular photodynamic therapy. 相似文献
486.
Deeg HJ; Graham TC; Gerhard-Miller L; Appelbaum FR; Schuening F; Storb R 《Blood》1989,74(7):2592-2595
Ten dogs were given 9.2 Gy of total body irradiation and autologous bone marrow infusion followed by ten daily transfusions of leukocytes for a total of 11.5 to 36.2 (median, 18.8) x 10(8)/kg obtained via leukapheresis from histoincompatible unrelated donors. Four dogs were given unirradiated leukocytes, and all developed graft-versus-host disease (GVHD). In contrast, only two of three dogs given leukocytes irradiated with 20 mJ/cm2 of ultraviolet (UV) light (200 to 300 nm), and none of three dogs given leukocytes irradiated with 1,000 mJ/cm2 developed GVHD. These data indicate that UV irradiation abrogates the alloreactive potential of transfused leukocytes, and suggest that UV irradiation can be used to prevent the development of transfusion- induced GVHD. 相似文献
487.
Recent studies demonstrated that patients with carpal tunnel syndrome (CTS) have signs of thermal and mechanical hyperalgesia in extra‐median territories suggesting an involvement of central pain mechanisms. As previous studies included patients with shoulder/arm symptoms or neck pain, a potential influence of these coexisting disorders cannot be excluded. This study therefore evaluated whether widespread sensory changes (hypoesthesia or hyperalgesia) are present in patients with unilateral CTS in the absence of coexisting disorders. Twenty‐six patients with unilateral CTS with symptoms localised to their hand and 26 healthy controls participated in the study. A comprehensive quantitative sensory testing (QST) protocol including thermal and mechanical detection and pain thresholds was performed over the hands (median, ulnar and radial innervation area), lateral elbows, neck and tibialis anterior muscle. Patients with CTS demonstrated thermal and mechanical hypoesthesia in the hand but not at distant sites. Thermal or mechanical hyperalgesia was not identified at any location with traditional QST threshold testing. However, patients with CTS rated the pain during thermal pain testing significantly higher than healthy participants. This was especially apparent for heat pain ratings which were elevated not only in the affected hand but also in the neck and tibialis anterior muscle. In conclusion, CTS alone in the absence of coexisting neck and arm pain does not account for sensory changes outside the affected hand as determined by traditional QST threshold testing. Elevated pain ratings may however be an early indication of central pain mechanisms. 相似文献
488.
细胞间黏附分子与胃癌侵袭、转移关系的研究进展 总被引:1,自引:0,他引:1
细胞间黏附分子-1(intercellularadhesionmolecule-1,ICAM-1)是体内重要的细胞活性分子,不仅参与了机体免疫过程及炎症反应,而且还通过与其相应配体的结合,介导癌细胞与不同细胞、基质的黏附,最终使癌细胞逃避免疫监视,利于侵袭转移.近年来,对ICAM-1与恶性肿瘤侵袭转移关系的研究已成为研究热点,其在肿瘤侵袭转移中的作用日益受到众多学者的重视.现就其近年的文献从ICAM-1的结构、生物学特征、在胃癌组织中的表达及作用机制等几个方面作一综述. 相似文献
489.
Antigen expression and polymerase chain reaction amplification of mantle cell lymphomas 总被引:3,自引:0,他引:3
Molot RJ; Meeker TC; Wittwer CT; Perkins SL; Segal GH; Masih AS; Braylan RC; Kjeldsberg CR 《Blood》1994,83(6):1626-1631
Flow immunophenotyping, DNA content analysis, and polymerase chain reaction (PCR) amplification for t(11;14) and t(14;18) were performed on 11 cases of typical mantle cell lymphoma (MCL), 5 cases of apparent MCL with proliferation centers (MCL-PC), and 5 cases of small lymphocytic lymphoma (SLL). Immunophenotyping showed IgM (P < .001), Ig light (P < .001), and CD20 (P < .001) expression to be more intense in MCL than in SLL. In MCL-PC, the mean intensity of IgM, Ig light chain, and CD20 expression was intermediate to the intensities observed in MCL and SLL. Furthermore, in contrast to SLL, all MCL and 4 of 5 MCL-PC cases exhibited stronger CD20 than CD19 expression. CD10 expression was not observed in any case and CD5 expression was present in all SLL and MCL-PC cases and in 9 of 11 MCL cases. DNA content analysis showed an S- phase fraction of less than 3% in all cases studied and, except for 1 MCL case, all lymphomas were DNA diploid. The t(11;14) breakpoint junctions involving the bcl-1 major translocation cluster were amplified by PCR in 4 of 11 (36%) MCL cases and in none of the MCL-PC or SLL cases. The t(14;18) involving the bcl-2 major breakpoint region was not identified by PCR in any case. We conclude that the level of expression of surface antigens and the rapid detection of t(11;14) by PCR are potentially useful for distinguishing MCL and SLL in the clinical setting. Further investigations as to the biologic relationship between MCL, MCL-PC, and SLL, and the utility of t(11;14) PCR in these lymphomas are warranted. 相似文献