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BioRxiv : the Preprint Server For... Jul 2023The small size and flexibility of G protein-coupled receptors (GPCRs) have long posed a significant challenge to determining their structures for research and...
The small size and flexibility of G protein-coupled receptors (GPCRs) have long posed a significant challenge to determining their structures for research and therapeutic applications. Single particle cryogenic electron microscopy (cryoEM) is often out of reach due to the small size of the receptor without a signaling partner. Crystallization of GPCRs in lipidic cubic phase (LCP) often results in crystals that may be too small and difficult to analyze using X-ray microcrystallography at synchrotron sources or even serial femtosecond crystallography at X-ray free electron lasers. Here, we determine the previously unknown structure of the human vasopressin 1B receptor (V1BR) using microcrystal electron diffraction (MicroED). To achieve this, we grew V1BR microcrystals in LCP and transferred the material directly onto electron microscopy grids. The protein was labeled with a fluorescent dye prior to crystallization to locate the microcrystals using cryogenic fluorescence microscopy, and then the surrounding material was removed using a plasma-focused ion beam to thin the sample to a thickness amenable to MicroED. MicroED data from 14 crystalline lamellae were used to determine the 3.2 Å structure of the receptor in the crystallographic space group 1. These results demonstrate the use of MicroED to determine previously unknown GPCR structures that, despite significant effort, were not tractable by other methods.
PubMed: 37461729
DOI: 10.1101/2023.07.05.547888 -
Journal of Personalized Medicine Sep 2023The objective of this manuscript was to review the indications, efficacy, and safety of a 585 nm pulsed dye laser (PDL) in non-malignant laryngeal lesions. Following the... (Review)
Review
The objective of this manuscript was to review the indications, efficacy, and safety of a 585 nm pulsed dye laser (PDL) in non-malignant laryngeal lesions. Following the PRISMA statement recommendations, three independent authors searched for articles published in PubMed/MEDLINE, the Cochrane Library, Google Scholar, Scielo, and Web of Science. A bias analysis was performed following NICE guidance tools. From the 506 identified publications, 19 observational studies met the inclusion criteria. The PDL improves vocal quality objectively and subjectively in vascular lesions ( < 0.005) and improves vocal quality in patients with dysplasia/leukoplasia without changing the natural history of the disease compared to other treatments. Reinke's edema and granulomas require an average of 1.5 PDL sessions for resolution. Treatment of recurrent respiratory papillomatosis requires multiple sessions, with complete remission achieved in 50-70% of patients. Regardless of the lesion, the tolerance of the procedure under local anesthesia is exceptional (84-97%), and the results in terms of regression and vocal quality are promising. The complication rate is minimal, and the procedure does not interfere with other treatment alternatives. There is no consensus on laser settings. The lack of consistent use in evaluating vocal outcomes, whether objective or subjective, prevents the comparability between studies. The 585 nm pulsed dye laser appears to be an effective and safe therapeutic option in patients with non-malignant laryngeal pathology. Future controlled studies are needed to compare the 585 nm pulsed dye laser with other lasers or cold instrument procedures.
PubMed: 37763142
DOI: 10.3390/jpm13091374 -
Skin Research and Technology : Official... Nov 2023An excessive proliferation of fibroblasts and collagen synthesis after an injury may lead to a benign fibrous tumor, known as keloid, which does not regress...
INTRODUCTION
An excessive proliferation of fibroblasts and collagen synthesis after an injury may lead to a benign fibrous tumor, known as keloid, which does not regress spontaneously. Earlobes are a very frequent site of onset, since after a trauma (i.e., piercing) keloids may develop either on the helix and on the anterior or posterior lobe, from a few months up to several years after the injury.
OBJECTIVES
To report the effectiveness of a combined protocol of CO2 laser + Dye laser + a portable Blue LED Light medical device for Photobiomodulation Therapy (EmoLED®).
METHODS
Fifty-two patients with a total of 56 ear keloids have been treated in the same session with a single CO2 laser procedure + a pulsed Dye laser procedure with an adjunctive EmoLED® procedure for 3 up to 6 min. A monthly follow-up has been performed with an adjunctive EmoLED® session in case of signs of inflammation.
RESULTS
Among 56 treated keloids, 89.3% of them (50/56) did not recur during a follow-up period (from 6 up to 24 months, mean 16.3 months) while six keloids recurred (6/56, 10.7%) with mild thickening of the scar, thus requiring further treatments.
CONCLUSIONS
Even if an excellent outcome obtained by the synergistic effect of combined laser treatments has already been described (i.e., CO2 laser + Dye Laser), the present study showed the adjuvant procedure with EmoLED® can reduce significantly the risk of keloids recurrences.
Topics: Humans; Keloid; Inflammation; Lasers, Gas; Recurrence; Light; Treatment Outcome
PubMed: 38009040
DOI: 10.1111/srt.13506 -
Indian Dermatology Online Journal 2023The role of lasers in the treatment of standard therapy-resistant inflammatory dermatoses and connective tissue disorders has been controversial and evidence supporting...
INTRODUCTION
The role of lasers in the treatment of standard therapy-resistant inflammatory dermatoses and connective tissue disorders has been controversial and evidence supporting the role of lasers in this setting is scarce.
OBJECTIVE
To assess the efficacy of lasers in the management of inflammatory dermatoses and connective tissue disorders (CTD).
MATERIALS AND METHODS
A retrospective case review of all inflammatory dermatoses/connective tissue diseases treated in a tertiary laser clinic between March 2010 and 2020 was undertaken.
RESULTS
A total of 60 cases (48 = female) were included and the average age was 51 years (range 21 to 74). The following conditions were treated: scleroderma = 22 (37%), granuloma faciale = 10 (17%), sarcoidosis = 8 (13%), discoid lupus erythematosus = 7 (12%), and systemic lupus erythematosus = 2 (3%). Other diagnoses included necrobiosis lipoidica, pyoderma vegetans, hypertrophic lichen planus, and dermatomyositis. The most common type of laser used was pulsed dye laser (PDL) in = 41 (68%) cases. Eight (13%) patients received treatment with the carbon dioxide (CO) laser. The most common site treated was the face. A good response with a marked reduction of signs was seen in 62% of patients while 10% of the patients did not respond to laser treatment. Self-limiting complications included purpura and hyperpigmentation.
LIMITATIONS
Lack of objective assessment and outcome measures.
CONCLUSIONS
This is the largest cohort of patients to have undergone laser treatment for inflammatory dermatoses/connective tissue disease. Based on this retrospective review, we conclude that lasers can be a useful adjunct in the management of otherwise difficult-to-treat selected inflammatory and connective tissue diseases.
PubMed: 37727556
DOI: 10.4103/idoj.idoj_439_22 -
The Journal of Dermatological Treatment Dec 2023Although pulsed dye laser (PDL) is the treatment of choice for port-wine stains (PWS), clinical resistance to PDL has been observed in 20-30% of cases. Several... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Although pulsed dye laser (PDL) is the treatment of choice for port-wine stains (PWS), clinical resistance to PDL has been observed in 20-30% of cases. Several alternative treatment modalities have been introduced; however, there is still a lack of definite recommendations regarding the optimal treatment for difficult-to-treat PWS.
OBJECTIVE
We aimed to systematically review and analyze the comparative effectiveness among treatments for problematic PWS.
METHODS & MATERIALS
We systematically searched for comparative studies assessing treatments for patients with difficult-to-treat PWS through relevant biomedical databases until August 2022. A Network Meta-Analysis (NMA) was conducted to estimate the odds ratio (OR) for all pairwise comparisons. The primary outcome is the improvement of lesions of more than 25%.
RESULTS
Of the 2498 studies identified, six treatments from five studies were available for NMA. Compared with 585 nm short-pulsed dye laser (SPDL), intense pulsed light (IPL) was the most effective in clearing lesions (OR 11.81, 95% CI 2.15 to 64.89, very low confidence rating), followed by 585 nm long-pulsed dye laser (LPDL) (OR 9.95, 95% CI 1.75 to 56.62, very low confidence rating). The 1064 nm NdYAG, 532 nm NdYAG, and LPDL >585 nm exhibited potential superiority over SPDL 585 nm, although statistical significance was not observed.
CONCLUSIONS
IPL and 585 nm LPDL are likely to be more effective than 585 nm SPDL for treating difficult-to-treat PWS. Well-designed clinical trials are warranted to confirm our findings.
Topics: Humans; Lasers, Dye; Low-Level Light Therapy; Network Meta-Analysis; Port-Wine Stain; Treatment Outcome
PubMed: 37424384
DOI: 10.1080/09546634.2023.2231582 -
Transfusion Medicine and Hemotherapy :... Apr 2024Before being implemented in daily clinical routine, new production strategies for platelet concentrates (PCs) must be validated for their efficacy. Besides in vitro...
INTRODUCTION
Before being implemented in daily clinical routine, new production strategies for platelet concentrates (PCs) must be validated for their efficacy. Besides in vitro testing, the establishment of new methods requires the labeling of platelets for in vivo studies of platelets' survival and recovery. Indocyanine green (ICG) is a Food and Drug Administration-approved near-infrared (NIR) fluorescent dye for diagnostic use in vivo, suitable for non-radioactive direct cell labeling of platelets.
METHODS
Platelets from PCs in storage solutions with different plasma concentrations were labeled with ICG up to concentrations of 200 μm. Whole blood (WB) was used as an ex vivo matrix to monitor the labeling stability of ICG-labeled platelets. The impact of labeling processes was assessed by the quantification of CD62P expression and PAC-1 binding as platelet function markers. Platelet aggregation was analyzed by light transmission aggregometry. ICG-labeling efficiency and stability of platelets were determined by flow cytometry.
RESULTS
Platelets from PCs could be successfully labeled with 10 μm ICG after 1 and 4 days of storage. The best labeling efficiency of 99.8% ± 0.1% (immediately after labeling) and 81% ± 6.2% (after 24 h incubation with WB) was achieved by plasma replacement by 100% platelet additive solution for the labeling process. Since the washing process slightly impaired platelet function, ICG labeling itself did not affect platelets. Immediately after the ICG-labeling process, plasma was re-added, resulting in a recovered platelet function.
CONCLUSION
We developed a Good Manufacturing Practice compatible protocol for ICG fluorescent platelet labeling suitable for survival and recovery studies in vivo as a non-radioactive labeling alternative.
PubMed: 38584698
DOI: 10.1159/000533623 -
Acta Dermato-venereologica Jan 2024Utilization of lasers and energy-based devices for surgical scar minimization has been substantially evaluated in placebo-controlled trials. The aim of this study was to... (Meta-Analysis)
Meta-Analysis
Utilization of lasers and energy-based devices for surgical scar minimization has been substantially evaluated in placebo-controlled trials. The aim of this study was to compare reported measures of efficacy of lasers and energy-based devices in clinical trials in preventing surgical scar formation in a systematic review and network meta-analyses. Five electronic databases, PubMed, Scopus, Embase, ClinicalTrials.gov, and the Cochrane Library, were searched to retrieve relevant articles. The search was limited to randomized controlled trials that reported on clinical outcomes of surgical scars with treatment initiation no later than 6 months after surgery and a follow-up period of at least 3 months. A total of 18 randomized controlled trials involving 482 participants and 671 postsurgical wounds were included in the network meta-analyses. The results showed that the most efficacious treatments were achieved using low-level laser therapy) (weighted mean difference -3.78; 95% confidence interval (95% CI) -6.32, -1.24) and pulsed dye laser (weighted mean difference -2.46; 95% CI -4.53, -0.38). Nevertheless, low-level laser therapy and pulsed dye laser demonstrated comparable outcomes in surgical scar minimization (weighted mean difference -1.32, 95% CI -3.53, 0.89). The findings of this network meta-analyses suggest that low-level laser therapy and pulsed dye laser are both effective treatments for minimization of scar formation following primary closure of surgical wounds with comparable treatment outcomes.
Topics: Humans; Network Meta-Analysis; Cicatrix; Lasers, Dye; Databases, Factual; Low-Level Light Therapy
PubMed: 38189223
DOI: 10.2340/actadv.v104.18477 -
Micromachines Dec 2023Optofluidic dye lasers integrated into microfluidic chips are promising miniature coherent light sources for biosensing. However, achieving the accurate and efficient...
Optofluidic dye lasers integrated into microfluidic chips are promising miniature coherent light sources for biosensing. However, achieving the accurate and efficient tuning of lasers remains challenging. This study introduces a novel pneumatically tunable optofluidic distributed feedback (DFB) dye laser in a multilayer microfluidic chip. The dye laser device integrates microfluidic channels, grating structures, and vacuum chambers. A second-order DFB grating configuration is utilized to ensure single-mode lasing. The application of vacuum pressure to the chambers stretches the soft grating layer, enabling the sensitive tuning of the lasing wavelength at a high resolution of 0.25 nm within a 7.84 nm range. The precise control of pressure and laser tuning is achieved through an electronic regulator. Additionally, the integrated microfluidic channels and optimized waveguide structure facilitate efficient dye excitation, resulting in a low pump threshold of 164 nJ/pulse. This pneumatically tunable optofluidic DFB laser, with its high-resolution wavelength tuning range, offers new possibilities for the development of integrated portable devices for biosensing and spectroscopy.
PubMed: 38258186
DOI: 10.3390/mi15010068 -
Scientific Reports Oct 2023Integrated optofluidic devices have become subjects of high interest for rapid biosensor devices due to their unique ability to combine the fluidic processing of small...
Integrated optofluidic devices have become subjects of high interest for rapid biosensor devices due to their unique ability to combine the fluidic processing of small volumes of microfluidics with the analysis capabilities of photonic structures. By integrating dynamically reconfigurable optofluidic lasers on-chip, complex coupling can be eliminated while further increasing the capabilities of sensors to detect an increasing number of target biomarkers. Here, we report a polydimethylsiloxane-based device with two on-chip fluidic distributed feedback (DFB) laser cavities that are integrated with an orthogonal analyte channel for multiplexed fluorescence excitation. One DFB grating is filled with 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran dissolved in dimethyl sulfoxide. The second grating is filled with rhodamine 6G dissolved in a diluted ethylene glycol solution. We present characterization of both lasers through analysis of the lasing spectra for spectral narrowing along with a power series to observe threshold behavior. We then demonstrate simultaneous detection of two different fluorescent microbeads as a proof of concept for scalable, single biomarker analysis using on-chip optofluidic lasers.
Topics: Humans; Lasers, Dye; Feedback; Optics and Photonics; Coloring Agents; Microfluidics
PubMed: 37803034
DOI: 10.1038/s41598-023-42671-4 -
Journal of Biomedical Optics Jun 2024Preparation of a recipient cytoplast by oocyte enucleation is an essential task for animal cloning and assisted reproductive technologies in humans. The femtosecond...
SIGNIFICANCE
Preparation of a recipient cytoplast by oocyte enucleation is an essential task for animal cloning and assisted reproductive technologies in humans. The femtosecond laser is a precise and low-invasive tool for oocyte enucleation, and it should be an appropriate alternative to traditional enucleation by a microneedle aspiration. However, until recently, the laser enucleation was performed only with applying a fluorescent dye.
AIM
This work is aimed to (1) achieve femtosecond laser oocyte enucleation without applying a fluorescent dye and (2) to study the effect of laser destruction of chromosomes on the structure and dynamics of the spindle.
APPROACH
We applied polarized light microscopy for spindle visualization and performed stain-free mouse and human oocyte enucleation with a 1033 nm femtosecond laser. Also, we studied transformation of a spindle after metaphase plate elimination by a confocal microscopy.
RESULTS
We demonstrated a fundamental possibility of inactivating the metaphase plate in mouse and human oocytes by 1033 nm femtosecond laser radiation without applying a fluorescent dye. Irradiation of the spindle area, visualized by polarized light microscopy, resulted in partly or complete metaphase plate destruction but avoided the microtubules impairment. After the metaphase plate elimination, the spindle reorganized, however, it was not a complete depolymerization.
CONCLUSIONS
This method of recipient cytoplast preparation is expected to be useful for animal cloning and assisted reproductive technologies.
Topics: Animals; Mice; Oocytes; Humans; Female; Lasers; Spindle Apparatus; Microscopy, Confocal; Metaphase; Microscopy, Polarization
PubMed: 38812963
DOI: 10.1117/1.JBO.29.6.065002