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91.
The central portion of chronic wounds is often hypoxic and relatively hypothermic, representing a deficient energy supply of the tissue, which impedes wound healing or even makes it impossible. Water-filtered infrared-A (wIRA) is a special form of heat radiation with a high tissue penetration and a low thermal load to the skin surface. wIRA produces a therapeutically usable field of heat and increases temperature, oxygen partial pressure and perfusion of the tissue. These three factors are decisive for a sufficient tissue supply with energy and oxygen and consequently as well for wound healing, especially in chronic wounds, and infection defense. wIRA acts both by thermal and thermic as well as by non-thermal and non-thermic effects. wIRA can advance wound healing or improve an impaired wound healing process and can especially enable wound healing in non-healing chronic wounds. wIRA can considerably alleviate the pain and diminish wound exudation and inflammation and can show positive immunomodulatory effects.In a prospective, randomized, controlled study of 40 patients with chronic venous stasis ulcers of the lower legs irradiation with wIRA and visible light (VIS) accelerated the wound healing process (on average 18 vs. 42 days until complete wound closure, residual ulcer area after 42 days 0.4 cm² vs. 2.8 cm²) and led to a reduction of the required dose of pain medication in comparison to the control group of patients treated with the same standard care (wound cleansing, wound dressing with antibacterial gauze, and compression garment therapy) without the concomitant irradiation. Another prospective study of 10 patients with non-healing chronic venous stasis ulcers of the lower legs included extensive thermographic investigation. Therapy with wIRA(+VIS) resulted in a complete or almost complete wound healing in 7 patients and a marked reduction of the ulcer size in another 2 of the 10 patients, a clear reduction of pain and required dose of pain medication, and a normalization of the thermographic image. In a current prospective, randomized, controlled, blinded study patients with non-healing chronic venous stasis ulcers of the lower legs are treated with compression garment therapy, wound cleansing, wound dressings and 30 minutes irradiation five times per week over 9 weeks. A preliminary analysis of the first 23 patients of this study has shown in the group with wIRA(+VIS) compared to a control group with VIS an advanced wound healing, an improved granulation and in the later phase of treatment a decrease of the bacterial burden. Some case reports have demonstrated that wIRA can also be used for mixed arterial-venous ulcers or arterial ulcers, if irradiation intensity is chosen appropriately low and if irradiation is monitored carefully. wIRA can be used concerning decubital ulcers both in a preventive and in a therapeutic indication. wIRA can improve the resorption of topically applied substances also on wounds. An irradiation with VIS and wIRA presumably acts with endogenous protoporphyrin IX (or protoporphyrin IX of bacteria) virtually similar as a mild photodynamic therapy (endogenous PDT-like effect). This could lead to improved cell regeneration and wound healing and to antibacterial effects. In conclusion, these results indicate that wIRA generally should be considered for the treatment of chronic wounds.  相似文献   
92.
BACKGROUND: Antagonists of growth hormone-releasing hormone (GHRH) such as JV-1-38 can inhibit androgen-independent prostate cancer directly by several mechanisms and/or indirectly by suppressing growth hormone/insulin-like growth factor-I (GH/IGF-I) axis. To shed more light on the mechanisms involved, the effects of JV-1-38 on PC-3 human prostate cancer were compared with those of somatostatin analog RC-160 in vivo and in vitro. METHODS: Nude mice bearing PC-3 tumors received JV-1-38 (20 microg), RC-160 (50 microg) or a combination of JV-1-38 and RC-160. The concentration of IGF-I in serum and the expression of mRNA for IGF-II and vascular endothelial growth factor (VEGF) in tumor tissue were investigated. RESULTS: In vivo, the final volume of PC-3 tumors treated with JV-1-38 was significantly lowered by 49% (P < 0.01), whereas RC-160 exerted only 30% inhibition (NS), compared with controls. Combined use of both compounds augmented tumor inhibition to 63% (P < 0.001). Serum IGF-I levels were decreased only in mice treated with RC-160. JV-1-38 suppressed mRNA for IGF-II in PC-3 tumors by 42%, whereas RC-160 alone or in combination with JV-1-38 caused a 65% reduction. JV-1-38 and RC-160 used as single drugs decreased the expression of VEGF by 50%, and their combination caused a 63% reduction. In vitro, JV-1-38 inhibited the proliferation of PC-3 cells by 39%. This effect could be partially reversed by addition of IGF-I to the serum-free medium. RC-160 alone did not affect the PC-3 cell growth in vitro, but in combination with JV-1-38 it augmented the antiproliferative effect of the GH-RH antagonist to 72%. Exposure to JV-1-38 in vitro reduced the expression of mRNA for IGF-II in PC-3 cells by 55% but did not change VEGF mRNA levels, whereas RC-160 had no effect. CONCLUSIONS: The antiproliferative effect of JV-1-38 was not associated with the suppression of serum IGF-I and was only partially correlated with the expression of IGF-II and VEGF in PC-3 tumors, suggesting that other mechanisms play a role in the antitumor action of GHRH antagonists. Nevertheless, the stronger inhibition of tumor growth after combined treatment with JV-1-38 and RC-160 indicates that the interference with multiple local stimulatory factors leads to an enhanced inhibition of prostate cancer.  相似文献   
93.
The development of nephrotoxicity induced by cephaloridine (CER) has been reported to be due to reactive oxygen species (ROS). Protein kinase C (PKC) has been suggested to modulate the generation of ROS. We investigated the possible participation of ROS generation assessed by chemiluminescence (CL) and PKC activity in rat kidney cortical mitochondria in the development of CER-induced nephrotoxicity. We first evaluated the magnitude of the nephrotoxic damage caused by CER in rats. The plasma parameters and ultrastructural morphology changes were increased markedly 24hr after the treatment of rats with CER. We demonstrated that the treatment of rats with CER clearly evoked not only enhancement of Cypridina luciferin analog (CLA)-dependent CL intensity, but also the activation of PKC in mitochondria isolated from the kidney cortex of rats 1.5 and 3.5 hr after injection of the drug. These changes were detected in advance of those observed in plasma and by electron microscopy. The increase in CLA-dependent CL intensity detected in the kidney cortical mitochondria 1.5 and 3.5 hr after injection of CER was inhibited completely by the addition of superoxide dismutase, suggesting the generation of superoxide anion in these mitochondria during the early stages of CER-induced nephrotoxicity. These results suggest that the activation of PKC and the enhancement of superoxide anion generation in kidney cortical mitochondria precede the increases in plasma parameters and the electron micrographic changes indicative of renal dysfunction in rats treated with CER. Additionally, they suggest a possible relationship between PKC activation in mitochondria and free radical-induced CER nephrotoxicity in rats.  相似文献   
94.
目的 研究HBV前S1抗原(Pre-S1)在指导核苷(酸)类药物抗病毒治疗上的意义.方法 将HBeAg阳性患者经拉米夫定治疗获得完全应答并维持疗效6个月以上停药者以Pre-S1是否阳性分成两组,比较两组的远期疗效.结果 Pre-S1阴性组一年、二年远期持续应答率分别为80%、21.05%,差异有统计学意义(P<0.01).阳性组患者一年、二年远期持续应答率分别为65%、10.53%,差异有统计学意义(P<0.01).结论 检测Pre-S1可作为判断慢性乙型肝炎患者经核苷(酸)类药物治疗完全应答后远期疗效和预后的重要指标.  相似文献   
95.
OBJECTIVES: This study examined the measurement equivalence of the original paper-based vertical format of the EQ-5D visual analog scale (EQ VAS) with a touch-screen computer-based horizontal format. METHODS: A total of 314 subjects were administered two modes of the EQ VAS in a randomized crossover design. One mode was the original paper-based 20 cm vertical EQ VAS; the other mode was touch-screen-based. Measurement equivalence was assessed by testing the 95% confidence interval of the mean differences from an equivalence threshold of -3 to +3 points on the VAS and evaluating the intraclass correlation coefficient (ICC). RESULTS: The adjusted mean (SE) EQ VAS score was 80.96 (0.87) on the paper and 79.59 (0.85) on the touch-screen. The mean (CI) difference between scores on the two formats was 1.37 with a confidence interval of 0.175-2.559, wholly contained within the equivalence interval. The ICC was 0.75, indicating acceptable agreement between the two modes. Almost a third (30.1%) of the respondents reported identical scores on both formats. CONCLUSION: These results provide evidence for the measurement equivalence of this EQ VAS touch-screen administration mode with the original paper mode.  相似文献   
96.

Objective

To evaluate if the use of lidocaine gel applied to the cervix prior to manual vacuum aspiration (MVA) in addition to paracervical blockade is useful in reducing the level of pain associated with the procedure.

Methods

A total of 88 patients were randomized to receive either 5?mL of lidocaine gel or a placebo applied topically to the cervix 5 minutes prior to paracervical blockade. Both groups received the same drugs for pain control (tramadol hydrochloride, diazepam, and sodium diclofenac). A visual analogue scale (VAS) was used for evaluation of pain intensity at two times: 2 minutes before the blockade (directly after tenaculum clamping of the anterior aspect of the cervix) and after MVA of the uterine cavity.

Results

There was a statistically significant difference in pain intensity between the arms of the study. At the first evaluation time (cervical clamping), VAS pain score for the placebo group (control) was 3.6 (2.1) and that for the lidocaine gel group (case) was 1.2 (1.4) (P?<?0.01). At the second evaluation time (after manual vacuum aspiration), VAS pain score perceived by the control group was 5.3 (2.5) and that for the case group was 3.1 (1.9) (P?<?0.01). The use of lidocaine gel was not associated with any adverse effects of interest.

Conclusion

The use of a topical lidocaine gel plus paracervical blockade was effective in reducing the intensity of pain associated with MVA when compared to paracervical blockade alone.  相似文献   
97.
Melatonin, a hormone secreted by the pineal gland, can act on the central circadian oscillator in the suprachiasmatic nucleus of the hypothalamus. It has been proposed that melatonin or its analogues may be useful in restoring disturbed circadian rhythms in jet-lag, shift-work and some blind subjects, and as sleep-promoting agents. In the present study, the (−)- and (+)-enantiomers of N-acetyl-4-aminomethyl-6-methoxy-9-methyl-1,2,3,4-tetrahydrocarbazole (AMMTC) were separated and tested. The affinity of the enantiomers at the specific 2-[125I]iodomelatonin binding site in chick brain membranes was compared in competition assays, and their biological activity in a specific melatonin receptor bioassay, aggregation of pigment granules in Xenopus laevis melanophores. The (−)-enantiomer of AMMTC was 130-fold and 230-fold more potent than the (+)-enantiomer in competition radioligand binding assays and melanophores, respectively. Both enantiomers are melatonin receptor agonists; (−)-AMMTC is slightly more potent than melatonin itself. As the tetrahydrocarbazole nucleus holds the C-3 amido side-chain of AMMTC in a restricted conformation, the analogues will be useful in modelling the melatonin receptor binding site.  相似文献   
98.
OBJECTIVE: This study investigated the potential for predicting which patients would have a negative emotional reaction to bronchoscopy. METHODOLOGY: A questionnaire was distributed to 120 patients who had undergone diagnostic fibreoptic bronchoscopy. A visual analog scale to evaluate the patient's discomfort was adopted. Multiple linear regression analysis was used to determine factors significantly influencing discomfort. The regression model included the following variables: age, gender, symptoms, smoking habits, proximal bronchial brushing, distal bronchial brushing, bronchial washing, proximal transbronchial biopsy, transbronchial lung biopsy, examination time, the bronchoscopist's experience, and the patient's anxiety level. RESULTS: The bronchoscopist's experience (P = 0.001) and the patient's anxiety level (P < 0.001) were variables that significantly influenced discomfort. These results suggest that discomfort decreased with the bronchoscopist's experience and increased with the patient's anxiety regarding bronchoscopy. CONCLUSIONS: The results suggest that subjective discomfort can be predicted both by the bronchoscopist's experience and by a questionnaire about the patient's anxiety level before bronchoscopy. Therefore, it is recommended that the patient's anxiety level be determined through the use of a questionnaire before bronchoscopy, and that more experienced bronchoscopists should take charge if the patient is judged as being excessively anxious. If experienced bronchoscopists are unavailable, the more anxious patient should receive more sedatives.  相似文献   
99.
We previously showed that a new vitamin D analog, 1alpha(OH)D5 (D5), induced differentiation and inhibited the growth of breast cancer cells. In this report, we examined whether D5 specifically delivered to breast cancer cells could have any therapeutic effect. D5 was linked to Her-2 antibody using sulfosuccinimidyl 6-4 azido nitrophenylamido hexanode (SANPAH) as a linker. The Her-2 antibody selected in our study had no significant effect on the in vitro or in vivo growth of breast cancer cells; however, it had cell-differentiating action. In vitro, D5-Her-2 antibody conjugate (IMC) showed the ability to specifically bind to Her-2-expressing cells, to compete with Her-2 antibody for surface receptor and to cause internalization. IMC (equivalent to 5 microg Her-2 antibody given intraperitoneally once weekly for 6 weeks) significantly inhibited the growth of BT-474 cells transplanted into athymic mice. The in vivo growth-inhibitory effect of IMC treatment was similar to that observed in animals receiving D5 continuously as a dietary supplement. These results show that the targeted delivery of D5 by immunoconjugation to cell surface receptor antibodies may be of potential therapeutic value for the treatment of Her-2 positive breast cancer.  相似文献   
100.
Objective: To compare the pharmacokinetics of a long-acting FSH analog containing the hCG-β carboxyterminal peptide (recombinant hFSH–CTP) with native recombinant hFSH and describe the pharmacodynamics of recombinant hFSH–CTP after SC injection in female rhesus monkeys.

Design: Rhesus monkey study.

Setting: Academic research environment.

Animal(s): Ten female rhesus monkeys.

Intervention(s): Recombinant hFSH and recombinant hFSH–CTP were administered via a single SC or IV dose to rhesus monkeys, and serial phlebotomy was performed (n = 2 and N = 4 for SC recombinant hFSH and recombinant hFSH–CTP, respectively; for IV dosing, N = 1 in each group). An additional two monkeys were pretreated with SC ganirelix and received SC recombinant hFSH–CTP after confirmation of pituitary suppression.

Main Outcome Measure(s): Plasma disappearance rate of recombinant hFSH and recombinant hFSH–CTP and serum estradiol levels.

Result(s): The elimination half-life of recombinant hFSH–CTP was twofold and fourfold longer than that for recombinant hFSH after SC and IV dosing, respectively. The absorption half-life was approximately threefold longer for recombinant hFSH–CTP than for recombinant hFSH after SC administration. Recombinant hFSH–CTP stimulates estradiol secretion for 5–7 days after an isolated SC dose.

Conclusion(s): Addition of the hCG-β carboxyterminal peptide to hFSH-β results in an FSH analog with longer absorption and elimination half-lives compared with native hormone. This analog is capable of prolonged ovarian stimulation in rhesus monkeys after an isolated SC injection.  相似文献   

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