Photodynamic inhibition of acetylcholinesterase after two-photon excitation of copper tetrasulfophthalocyanine

Sequential two-photon (2-γ) activated copper tetrasulfophthalocyanine (CuPcS₄) was shown capable of inactivating acetylcholinesterase (ACE). ACE activity was measured photometrically by the Ellman method. Simultaneous irradiation of ACE in the presence of CuPcS₄ with 514 nm (183 mW/cm²) and 670 nm (86 mW/cm²) continuous wave (CW) light induced a 20–50% increase in enzyme inhibition as compared to one-photon (1-γ) irradiation, using either 514- or 670-nm (CW) light at the same fluences. The enzyme activity was not affected by CuPcS₄ or light alone, decreased linearly with the irradiation time, and was shown to be oxygen-dependent. We conclude that the photoinactivation of ACE with sequential 2-γ irradiation involves reactive oxygen species produced by the interaction of the upper excited T_n state of CuPcS₄ with molecular oxygen. As CuPcS₄ shows little activity as a conventional 1-γ photosensitizer, unwanted side effects such as prolonged skin sensitivity are eliminated rendering 2-γ photodynamic therapy advantageous for the treatment of selected medical applications.     

The effects of laser irradiation on <Emphasis Type="Italic">Trichophyton rubrum</Emphasis> growth

The effects of various laser wavelengths and fluences on the fungal isolate, Trichophyton rubrum, were examined in vitro. Standard-size isolates of T. rubrum were irradiated by using various laser systems. Colony areas were compared for growth inhibition on days 1, 3, and 6 after laser irradiation. Statistically significant growth inhibition of T. rubrum was detected in colonies treated with the 1,064-nm Q-switched Nd:YAG laser at 4 and 8 J/cm² and 532-nm Q-switched Nd:YAG laser at 8 J/cm². Q-switched Nd:YAG laser at 532- and 1,064-nm wavelengths produced significant inhibitory effect upon the fungal isolate T. rubrum in this in vitro study. However, more in vitro and in vivo studies are necessary to investigate if lasers would have a potential use in the treatment of fungal infections of skin and its adnexa.     

Benefits of the use of the CO<Subscript>2</Subscript> laser in orthodontics

Esthetics is an important factor for patients seeking orthodontic treatment, and not always is the orthodontist able to make adjustments on the gingival contour, and this aspect is neglected. Many orthodontists are familiar with the name laser. However, there is a lack of information regarding their application on the orthodontic practice. There are several options for the use of CO₂ lasers on surgical procedures of interest to orthodontists, especially on soft tissues. There is no evidence that the use of the CO₂ laser has any side effect or contraindication on surgical procedures. This paper reports a series of surgical procedures carried out on orthodontic patients. It is concluded that the carbon dioxide laser not only allows surgeons to enhance current surgical options for treatment but also have contributed to the evolution of a variety of new procedures that are now commonplace in oral surgery, and its use shows several benefits for the orthodontic patient.     

Transition from congress abstract to full publication for clinical trials presented at laser meetings

The present study aims to identify (1) what proportion of abstracts of clinical trials presented at The American Society for Laser Medicine and Surgery (ASLMS) annual meetings are published as full reports, (2) time to publication, and (3) factors that may predict the publication of research in peer-reviewed journals. Two investigators independently hand-searched all abstracts of the ASLMS meetings to identify all reports of clinical trials. Details of sample size, the country of origin, topic of research, type of presentation, type of laser, direction of outcome, and statistical significance were recorded for each abstract. To determine the full publication status of each study, The Cochrane Central Register of Controlled Trials, PubMed, and EMBASE was searched. A total of 198 abstracts were identified. Of these, 87 abstracts (44%) have been fully published. The average time from presentation at the meeting to full publication was 57 months (95% confidence interval = 52-61), and the estimated rate of abstracts published at 1, 2, and 4 years was 15, 30, and 38%, respectively. There is significant tendency for being fully published in high-power laser studies, with USA as country of origin, and orally presented. Our findings supports this opinion that conference abstracts can be an important source for systematic reviews and failure to identify trials presented in congresses might threaten the validity of systematic reviews.     

Adverse effects reported in epilatory ruby laser treatment

A retrospective study was conducted to investigate the incidence of reported adverse responses after epilatory laser treatment to control the growth of facial hair in patients with polycystic ovary syndrome. Forty-eight patients received a median of 6 (range 2–11) treatments with an Aesculap ruby laser during a 704 day monitoring period at Salisbury District Hospital. Nine adverse skin responses such as blistering, scabbing, sustained localised erythematous reactions or hyperpigmentation were reported. The energy output of the laser was also recorded at the start of every clinical session during this period using an external energy meter. The measured energy output of the laser was plotted alongside incidents of adverse responses, although no statistically significant correlation was found. The question of whether or not some adverse effects in ruby laser treatment can be attributed to laser performance remains open.     

Ureteroscopic holmium laser lithotripsy in patients with renal impairment

Objectives In this study, we try to evaluate the efficacy and safety of holmium lasers for treatment of ureteric stones in patients with renal impairment or obstructive anuria. Patients and methods Twenty-six patients were included in this study, of which 20 patients presented with elevated blood urea and serum creatinine (2.1–7.6 mg%), and six patients presented with calcular anuria (mean serum creatinine 22 mg%). None of the patients had a ureteric stent or nephrostomy tube before the ureteroscopy. All patients were treated with holmium laser. A stone basket or grasper was used to remove significant stone fragments at the end of the procedure in seven patients. In these seven patients, ureteric stents were placed at the end of the procedure. Results All patients were free of any stone fragments at 1 week and at 3 months postoperatively. In all patients, including the six with obstructive anuria, the renal impairment resolved or improved as evidenced by normalization or fall in blood urea and creatinine. Thus, in this small group of uremic patients, the success rate for treatment of ureteral stone was 100%. Conclusions A holmium laser is a safe and effective modality of ureteroscopic lithotripsy in patients with significant renal impairment or even obstructive anuria. The use of holmium laser with ureteroscopy may be considered in this group of patients as long as the general condition of the patient permits the safe administration of anesthesia.     

Peniscopically controlled CO2 laser excision for conservative treatment of in situ and T1 penile carcinoma: report on 224 patients

Objective

To evaluate the outcome of peniscopically controlled laser excision of early-stage penile carcinoma.

Methods

Patients treated from 1982 to 2006 were investigated. The primary treatment was excisional surgery alone for in situ or initially invasive flat tumors, and reductive chemotherapy followed by surgery for the exophytic lesions. All excisional procedures were conducted by CO₂ laser under peniscopic control.

Results

Of a total of 224 patients, 111 underwent partial excision of the glans and/or coronal sulcus surface, and 113 total surface excision. Forty patients underwent reductive chemotherapy. Complete excision was obtained in 221 cases (98.7%) at lateral margins and in 217 cases (96.9%) at deep margin. Postoperative complications were negligible. Overall, the 10-yr recurrence rate was 17.5% (95% confidence interval, 16.4–18.6%), and apparently was not affected by the in situ or invasive nature of the lesion. Amputation was required in nine patients, for a 10-yr amputation rate of 5.5% (range, 5.2–5.7%). In the remaining cases, organ form and curvature were preserved, with satisfactory cosmetic and functional results.

Conclusions

Early-stage penile carcinomas can be effectively treated with the organ-sparing strategy described here. Because local recurrences occur in a minority of patients and can be safely treated, organ preservation is compatible with local disease control. Reductive systemic chemotherapy in selected exophytic cases broadens the indication for our conservative approach.     

An evaluation of semen characteristics in men 45 years of age or older after daily dosing with tadalafil 20mg: results of a multicenter, randomized, double-blind, placebo-controlled, 9-month study

OBJECTIVES: Assess the effects on spermatogenesis of daily tadalafil 20mg over three spermatogenesis cycles in men >or= 45 yr. METHODS: In this double-blind, placebo-controlled, noninferiority study, healthy men (or with mild erectile dysfunction) were randomized to receive tadalafil 20mg (n=125) or placebo (n=128) for 9 mo followed by a 6-mo, treatment-free period. Semen and serum samples were provided at baseline and every 10-12 wk. The primary outcome was the proportion of subjects with >or= 50% reduction in sperm concentration at end point. Secondary outcomes included sperm concentration, number per ejaculate, motility and morphology; serum concentrations of testosterone, luteinizing and follicle-stimulating hormones; and tolerability. RESULTS: Of 253 men enrolled, 191 (75%) completed treatment phase: 2 of 96 (2.1%, placebo) and 12 of 95 (12.6%, tadalafil) subjects had >or= 50% reduction in sperm concentration. Tadalafil was noninferior to placebo because the upper 95% confidence interval for the difference in proportions of tadalafil and placebo subjects with a >or= 50% reduction in sperm concentration was 17.5%, significantly less than the prespecified noninferiority margin of 20% (p=0.015). Ninety-four percent (179 of 191) of men completed the 6-mo, treatment-free period: Baseline sperm concentration levels were restored in 8 of 12 (tadalafil) and 1 of 2 (placebo) men. There were no significant differences between groups in secondary end points. Common treatment-emergent adverse events were headache, back pain, dyspepsia, gastroesophageal reflux disease, and myalgia. Twelve (9.6%) tadalafil and seven (5.5%) placebo subjects discontinued because of adverse events. CONCLUSIONS: This study demonstrated no deleterious effects of 9 mo of daily tadalafil 20mg on spermatogenesis or hormones related to testicular function in men >or= 45 yr.     

Retinoids, 585-nm Laser,and Carbon Dioxide Laser: A Numeric Comparison of Neocollagen Formation in Photoaged Hairless Mouse Skin

Background  A variety of new methods for treating photoaging have been recently introduced. There has been increasing interest in comparing the relative efficacy of multiple methods for photoaging. However, the efficacy of a single method is difficult to assess from the data reported in the literature. Methods  Photoaged hairless mice were randomly divided into seven treatment groups: control, retinoids (tretinoin and adapalene), lasers (585 nm and CO₂), and combination groups (585 nm + adapalene and CO₂ + adapalene). Biopsies were taken from the treated regions, and the results were analyzed based on the repair zone. The repair zones of the various methods for photoaging were compared. Results  Retinoids produced a wider repair zone than the control condition. The 585-nm and CO₂ laser resurfacing produced a result equivalent to that of the control condition. A combination of these lasers with adapalene produced a wider repair zone than the lasers alone, but the combination produced a result equivalent to that of adapalene alone. Conclusion  Retinoids are potent stimuli for neocollagen formation. The 585-nm or CO₂ laser alone did not induce more neocollagen than the control condition. In addition, no synergistic effect was observed with the combination treatments. The repair zone of the combination treatment is mainly attributable to adapalene.