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31.
Evaluating the safety and efficacy of the 1,440‐nm laser in the treatment of photodamage in Asian skin 下载免费PDF全文
Shoshana Marmon MD PhD Samantha Y. N. Shek MBBS C.K. Yeung MD MBBS Nicola P.Y. Chan MRCP Johnny CY Chan MBBS Henry H.L. Chan MD PhD FRCP 《Lasers in surgery and medicine》2014,46(5):375-379
Background and Objective
As the demand for diminished procedure‐associated downtime continues to increase, nonablative fractional laser resurfacing is becoming a more popular intervention in the progression of photoaging. Patients with pigmented skin and a mild degree of photodamage may be particularly suited for a less intensive laser treatment. In this study, we have evaluated the safety and efficacy of a low energy, low density 1,440‐nm fractional laser in the treatment of multiple signs of photoaging including dyspigmentation, wrinkling, tissue laxity, enlarged pores, and skin roughness in Asians.Study Design/Materials and Methods
Ten Chinese subjects with Fitzpatrick skin types III–V and visible signs of photodamage participated in this study. Patients received four treatments at 2‐week intervals with a 1,440‐nm diode‐based fractional laser. Photographs were taken at baseline, 2 weeks after each of the first three treatments and 4 weeks after the final treatment. Images were evaluated independently by two physicians. Clinical improvement and adverse events were analyzed. Discomfort, heat sensation and overall patient satisfaction associated with the procedure were also quantified.Results
In this prospective single‐arm study, signs of photoaging were examined after treatment with the 1,440‐nm laser. Here we show that a series of four treatments with this device produced a mild improvement in skin texture, pigmentation, and wrinkling. Changes in pore size and skin laxity failed to reach statistical significance. Immediate after‐effects of the procedure included erythema and edema which were transient and left no permanent sequela. A significant proportion of patients reported some degree of discomfort during the procedure despite use of a topical anesthetic. One patient developed a discrete, localized area of post‐inflammatory hyperpigmentation which completely resolved by the final follow up visit.Conclusion
The low energy, low density nonablative 1,440‐nm fractional laser produces a mild improvement in select signs of photodamage after four treatments without any long‐term adverse effects. Lasers Surg. Med. 46:375–379, 2014. © 2014 Wiley Periodicals, Inc. 相似文献32.
JME Kovoor RD Thomas HS Chandrashekhar PN Jayakumar S Pillai SK Shankar 《Journal of Medical Imaging and Radiation Oncology》2007,51(5):406-411
Early and non‐invasive evaluation of hydatid infestation of brain and spine is of paramount importance, especially in endemic areas. We present a spectrum of imaging findings in neurohydatidosis with a brief review of literature. 相似文献
33.
PN McDOUGALL PM LOUGHNAN NT CAMPBELL M HOCHMANN BJ TIMMS WW BUTT 《Journal of paediatrics and child health》1995,31(4):292-296
Objective: To report ventilation strategies, survival and complications in 39 outborn infants treated with high frequency oscillatory ventilation (HFOV).
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction. 相似文献
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction. 相似文献
34.
Au WY Lie AK Kwong YL Shek TW Hawkins BR Lai KN Tang SC Lo CM Fan ST Liu CL Chan GC Chau EM Chiu SW Liang R 《Leukemia & lymphoma》2002,43(7):1403-1407
Post-transplantation lymphoproliferative disease (PTLD) is an unique iatrogenic complication after bone marrow transplantation (BMT) and solid organ transplantation (SOTx). The pattern of EBV related lymphoma in Chinese is different from Caucasians. We surveyed the incidence, clinical and pathological spectrum of PTLD among 541 cases of allogeneic BMT, 145 cases of renal transplant, 35 cases of heart/lung transplantation and 146 cases of orthotopic liver transplantation (OLT). From 1994 to 2001, 13 consecutive cases of PTLD were diagnosed, ranging from disseminated NK cell lymphoma to localized plasmacytoma. Both donor and recipient derived PTLD was documented. Disease was often heralded by cytomegaloviral disease and antithymocyte globulin (ATG) usage. Two cases were diagnosed post-mortem, and six patients died of PTLD at a median of 3 months. Complete and partial remission was only achieved in 3 and 2 cases, respectively, despite a range of treatment (reduced immunosuppression, explantation, radiotherapy, combination chemotherapy, donor lymphocytes, autologous marrow infusion and rituximab). Most responding patients died subsequently of rejection, infection and graft versus host disease (GVHD). The incidence of PTLD is not increased in Chinese patients. However, some patients may be at increased risk, especially mismatched allogeneic BMT, parental OLT (especially involving young infants) and heavy ATG exposure. 相似文献
35.
36.
N-Methyl-1,6-dihydropyridine-2-carbaldoxime hydrochloride, the pro-drug of 2-PAM, was found to be converted in vivo to 2-PAM, rapidly and quantitatively. The significantly changed properties of the pro-2-PAM resulted in a longer biological half-life and a favorable distribution of 2-PAM formed upon its oxidation. No new metabolite was found when pro-2-PAM was administered intravenously; however, a new metabolic product was formed when the pro-drug was given by oral route. 相似文献
37.
Lok IH Lee DT Yip SK Shek D Tam WH Chung TK 《American journal of obstetrics and gynecology》2004,191(2):546-550
OBJECTIVE: The purpose of this study was to evaluate 12-item General Health Questionnaire (GHQ-12) in screening for psychiatric morbidity after miscarriage. STUDY DESIGN: A prospective cohort study was carried out involving 222 patients. Six weeks after miscarriage, the GHQ-12 was applied. Psychiatric "case" or "non-case" was diagnosed by the psychiatrist with use of the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders-III-R. The patients were computer randomized into Groups A or B. A receiver operating characteristic (ROC) curve was constructed for Group A. The optimal cutoff value of GHQ-12 was determined, and this value was applied to Group B. The test characteristics were assessed. RESULTS: Twenty-seven patients were found to be psychiatric cases. An ROC with area under curve of 0.93 (95% CI 0.87-0.99, P<.001) was constructed. The best GHQ-12 cutoff score was > or =4 in detecting psychiatric caseness. A sensitivity of 83%, specificity of 90%, positive predictive value of 50%, and negative predictive value of 98% were obtained. CONCLUSION: GHQ-12 is an effective screening tool in detecting psychiatric morbidity after miscarriage. 相似文献
38.
Wang XS Tan TN Shek LP Chng SY Hia CP Ong NB Ma S Lee BW Goh DY 《Archives of disease in childhood》2004,89(5):423-426
Background and Aims: Over the past few decades, the prevalence of asthma has been increasing in the industrialised world. Despite the suggestion of a similar increase in Singapore, the 12 month prevalence of wheeze among schoolchildren in 1994 was 2.5-fold less than that reported in western populations. It was hypothesised that with increasing affluence in Singapore, the asthma prevalence would further increase and approach Western figures. A second ISAAC survey was carried out seven years later to evaluate this hypothesis. Methods: The cross-sectional data from two ISAAC questionnaire based surveys conducted in 1994 (n = 6238) and in 2001 (n = 9363) on two groups of schoolchildren aged 6–7 and 12–15 years were compared. The instruments used were identical and the procedures standardised in both surveys. Results: Comparing data from both studies, the change in the prevalence of current wheeze occurred in opposing directions in both age groups—decreasing in the 6–7 year age group (16.6% to 10.2%) but increasing to a small extent in the 12–15 year age group (9.9% to 11.9%). The 12 month prevalence of rhinitis did not change; there was an increase in the current eczema symptoms in both age groups. Conclusion: The prevalence of current wheeze, a surrogate measure of asthma prevalence, has decreased significantly in the 6–7 year age group. Eczema was the only allergic disease that showed a modest increase in prevalence in both age groups. 相似文献
39.
40.
How can transforming growth factor beta be targeted usefully to combat liver fibrosis? 总被引:32,自引:0,他引:32
Transforming growth factor beta-1 (TGF-beta 1) plays a pivotal role in tissue fibrogenesis. Understanding the factors that control resolution of fibrosis is critical to devising means to combat clinical fibrosis. Future challenges would include designing ways to block the fibrosis-specific actions of TGF-beta.Blockade of transforming growth factor beta (TGF-beta) activity in vivo in animal models has proven to be an effective means of inhibiting the fibrotic response to injury in various organs. Similarly, transgenic animals in which TGF-beta 1 expression is artificially enhanced show marked spontaneous fibrosis or increased fibrotic response to injury. TGF-beta is known to effect fibroplasias, not only by its well known action of increasing extracellular matrix synthesis but also by coordinately regulating key proteins which mediate connective tissue homeostasis. This includes down-regulation of interstitial collagenase and other matrix metalloproteinases and up-regulation of antiproteases such as tissue inhibitor of metalloproteinase I and plasminogen activator inhibitor. Whilst inhibition of TGF-beta activity appears to be well tolerated in rodents over several weeks, the ultimately lethal phenotype of TGF-beta 1 knockout mice warns us that this pluripotent cytokine is essential for normal health. Therefore, downstream pathways activated by TGF-beta, which might be specific for its fibrotic effects, might be more useful targets for human fibrotic disease therapy. For example, the TGF-beta response protein connective tissue growth factor may be a good target for antifibrotics but definitive evidence awaits development of suitable genetically modified animal models and specific inhibitors. 相似文献