ABSTRACT
INTRODUCTION: Oncologic esophagectomy is a two-cavity procedure with considerable morbidity and mortality. Complex anatomy and the proximity to major vessels constitute a risk for massive intraoperative hemorrhage. Currently, there is no conclusive consensus on the ideal anesthesiologic countermeasure in case of such immense blood loss. The objective of this work was to identify the most promising anesthesiologic management in case of intraoperative hemorrhage with regards to tissue perfusion of the gastric conduit during esophagectomy using hyperspectral imaging (HSI). MATERIAL AND METHODS: An established live porcine model (n=32) for esophagectomy was used with gastric conduit formation and simulation of a linear stapled side-to-side esophagogastrostomy. After a standardized procedure of controlled blood loss of about 1 L per pig, the four experimental groups (n=8 each) differed in anesthesiologic intervention i.e. (I) permissive hypotension, (II) catecholamine therapy using noradrenaline, (III) crystalloid volume supplementation and (IV) combined crystalloid volume supplementation with noradrenaline therapy. HSI tissue oxygenation (StO2) of the gastric conduit was evaluated and correlated with systemic perfusion parameters. Measurements were conducted before (T0) and after (T1) laparotomy, after hemorrhage (T2) and 60 minutes (T3) and 120 minutes (T4) after anesthesiologic intervention. RESULTS: StO2 values of the gastric conduit showed significantly different results between the four experimental groups with 63.3% (±7.6%) after permissive hypotension (I), 45.9% (±6.4%) after catecholamine therapy (II), 70.5% (±6.1%) after crystalloid volume supplementation (III) and 69.0% (±3.7%) after combined therapy (IV). StO2 values correlated strongly with systemic lactate values (r=-0.67; CI -0.77 to -0.54), which is an established prognostic factor. CONCLUSION: Crystalloid volume supplementation (III) yields the highest StO2 values and lowest systemic lactate values and therefore appears to be the superior primary treatment strategy after hemorrhage during esophagectomy with regards to microcirculatory tissue oxygenation of the gastric conduit.
ABSTRACT
Accurate intraoperative assessment of organ perfusion is a pivotal determinant in preserving organ function e.g. during kidney surgery including partial nephrectomy or kidney transplantation. Hyperspectral imaging (HSI) has great potential to objectively describe and quantify this perfusion as opposed to conventional surrogate techniques such as ultrasound flowmeter, indocyanine green or the subjective eye of the surgeon. An established live porcine model under general anesthesia received median laparotomy and renal mobilization. Different scenarios that were measured using HSI were (1) complete, (2) gradual and (3) partial malperfusion. The differences in spectral reflectance as well as HSI oxygenation (StO2) between different perfusion states were compelling and as high as 56.9% with 70.3% (± 11.0%) for "physiological" vs. 13.4% (± 3.1%) for "venous congestion". A machine learning (ML) algorithm was able to distinguish between these perfusion states with a balanced prediction accuracy of 97.8%. Data from this porcine study including 1300 recordings across 57 individuals was compared to a human dataset of 104 recordings across 17 individuals suggesting clinical transferability. Therefore, HSI is a highly promising tool for intraoperative microvascular evaluation of perfusion states with great advantages over existing surrogate techniques. Clinical trials are required to prove patient benefit.
Subject(s)
Hyperspectral Imaging , Kidney , Animals , Swine , Kidney/blood supply , Kidney/diagnostic imaging , Kidney/surgery , Hyperspectral Imaging/methods , Humans , Artificial Intelligence , Nephrectomy/methods , Perfusion/methodsABSTRACT
BACKGROUND: Of all ultraviolet (UV) radiations reaching the earth, UVA1 rays have a higher potential of penetrating and producing clinically harmful consequences. While UV radiations up to 370 nm are well-blocked by current sunscreens, a photoprotection gap remains for the UVA1 wavelengths between 370 and 400 nm. OBJECTIVE: This study was to assess under outdoor summer conditions the impact on pigmentation and skin ageing signs of a protection against UVA1 using methoxypropylamino cyclohexenylidene ethoxyethylcyanoacetate (MCE) filter added to a reference SPF50 sunscreen, in comparison with the same sunscreen without the MCE filter. MATERIALS AND METHODS: This prospective randomized comparative intra-individual study was conducted in 113 women in Brazil and China. Subjects had their face and two forearms exposed twice-daily to a 1-h outdoor sunlight exposure over 8 weeks. Before exposure, the SPF50 sunscreen containing 3% MCE was applied on one half-face and one forearm and the same reference product without MCE on the other half-face and forearm. Primary study endpoint was skin colour changes (chromametry). Other endpoints included expert panel grading of pigmentation and facial skin ageing, and naïve panel assessment of facial skin radiance and homogeneity. RESULTS: After 8 weeks, the skin was darker on both forearms but the increase in sun-induced pigmentation was smaller with the SPF50/MCE sunscreen. Expert panel evaluations showed no change in severity scores for pigmentation and a decreased severity scores for facial skin ageing in areas protected with the SPF50/MCE product: severity scores in areas protected with the SPF50 alone were either increased (pigmentation) or unchanged (skin ageing). Naïve panel evaluations of skin radiance and homogeneity showed statistically significant superiority of the SPF50/MCE product. CONCLUSION: Overall, this study demonstrates that a protection with the SPF50/MCE sunscreen significantly reduces pigmentation and ageing signs compared to the same SPF50 sunscreen.
Subject(s)
Pigmentation Disorders , Sunscreening Agents , Humans , Female , Sunscreening Agents/pharmacology , Sunscreening Agents/therapeutic use , Prospective Studies , Ultraviolet Rays/adverse effects , Sunlight/adverse effects , SkinABSTRACT
BACKGROUND: Benchmarking is a validated tool for outcome assessment and international comparison of best achievable surgical outcomes. The methodology is increasingly applied in pancreatic surgery and the aim of the review was to critically compare available benchmark studies evaluating distal pancreatectomy (DP). METHODS: A literature search of English articles reporting on benchmarking DP was conducted of the electronic databases MEDLINE and Web of Science (until April 2023). Studies on open (ODP), laparoscopic (LDP), and robotic DP (RDP) were included. RESULTS: Four retrospective multicenter studies were included. Studies reported on outcomes of minimally invasive DP only (n = 2), ODP and LDP (n = 1), and RDP only (n = 1). Either the Achievable Benchmark of Care™ method or the 75th percentile from the median was selected to define benchmark cutoffs. Robust and reproducible benchmark values were provided by the four studies for intra- and postoperative short-term outcomes. CONCLUSION: Benchmarking DP is a valuable tool for obtaining internationally accepted reference outcomes for open and minimally invasive DP approaches with only minor variances in four international cohorts. Benchmark cutoffs allow for outcome comparisons between institutions, surgeons, and to monitor the introduction of novel minimally invasive DP techniques.
Subject(s)
Laparoscopy , Pancreatectomy , Humans , Benchmarking , Retrospective Studies , Databases, FactualABSTRACT
BACKGROUND: Very young premenopausal women diagnosed with hormone receptor-positive, human epidermal growth factor receptor 2-negative (HR+HER2-) early breast cancer (EBC) have higher rates of recurrence and death for reasons that remain largely unexplained. PATIENTS AND METHODS: Genomic sequencing was applied to HR+HER2- tumours from patients enrolled in the Suppression of Ovarian Function Trial (SOFT) to determine genomic drivers that are enriched in young premenopausal women. Genomic alterations were characterised using next-generation sequencing from a subset of 1276 patients (deep targeted sequencing, n = 1258; whole-exome sequencing in a young-age, case-control subsample, n = 82). We defined copy number (CN) subgroups and assessed for features suggestive of homologous recombination deficiency (HRD). Genomic alteration frequencies were compared between young premenopausal women (<40 years) and older premenopausal women (≥40 years), and assessed for associations with distant recurrence-free interval (DRFI) and overall survival (OS). RESULTS: Younger women (<40 years, n = 359) compared with older women (≥40 years, n = 917) had significantly higher frequencies of mutations in GATA3 (19% versus 16%) and CN amplifications (CNAs) (47% versus 26%), but significantly lower frequencies of mutations in PIK3CA (32% versus 47%), CDH1 (3% versus 9%), and MAP3K1 (7% versus 12%). Additionally, they had significantly higher frequencies of features suggestive of HRD (27% versus 21%) and a higher proportion of PIK3CA mutations with concurrent CNAs (23% versus 11%). Genomic features suggestive of HRD, PIK3CA mutations with CNAs, and CNAs were associated with significantly worse DRFI and OS compared with those without these features. These poor prognostic features were enriched in younger patients: present in 72% of patients aged <35 years, 54% aged 35-39 years, and 40% aged ≥40 years. Poor prognostic features [n = 584 (46%)] versus none [n = 692 (54%)] had an 8-year DRFI of 84% versus 94% and OS of 88% versus 96%. Younger women (<40 years) had the poorest outcomes: 8-year DRFI 74% versus 85% and OS 80% versus 93%, respectively. CONCLUSION: These results provide insights into genomic alterations that are enriched in young women with HR+HER2- EBC, provide rationale for genomic subgrouping, and highlight priority molecular targets for future clinical trials.
Subject(s)
Breast Neoplasms , Humans , Female , Aged , Breast Neoplasms/drug therapy , Receptor, ErbB-2/metabolism , Prognosis , Genomics , Class I Phosphatidylinositol 3-Kinases/geneticsABSTRACT
Schizophrenia has been associated with structural brain abnormalities and cognitive deficits that partly change during the course of illness. In the present study, cortical thickness in five subregions of the cingulate gyrus was assessed in 44 patients with schizophrenia-spectrum disorder and 47 control persons and related to illness duration and memory capacities. In the patients group, cortical thickness was increased in the posterior part of the cingulate gyrus and related to illness duration whereas cortical thickness was decreased in anterior parts unrelated to illness duration. In contrast, cortical thickness was related to episodic and working memory performance only in the anterior but not posterior parts of the cingulate gyrus. Our finding of a posterior cingulate increase may point to either increased parietal communication that is accompanied by augmented neural plasticity or to effects of altered neurodegenerative processes in schizophrenia.
Subject(s)
Gyrus Cinguli , Schizophrenia , Cognition , Gyrus Cinguli/diagnostic imaging , Humans , Magnetic Resonance Imaging , Memory, Short-Term , Schizophrenia/complications , Schizophrenia/diagnostic imagingABSTRACT
Several epidemiological studies have revealed the involvement of nanoparticles (NPs) in respiratory and cardiovascular mortality. In this work, the focus will be on the effect of manufactured carbon black NPs for risk assessment of consumers and workers, as human exposure is likely to increase. Since the pulmonary circulation could be one of the primary targets of inhaled NPs, patients suffering from pulmonary hypertension (PH) could be a population at risk. To compare the toxic effect of carbon black NPs in the pulmonary circulation under physiologic and pathological conditions, we developed a new in vitro model mimicking the endothelial dysfunction and vascular dynamics observed in vascular pathology such as PH. Human pulmonary artery endothelial cells were cultured under physiological conditions (static and normoxia 21% O2) or under pathological conditions (20% cycle stretch and hypoxia 1% O2). Then, cells were treated for 4 or 6 h with carbon black FW2 NPs from 5 to 10 µg/cm2. Different endpoints were studied: (i) NPs internalization by transmission electronic microscopy; (ii) oxidative stress by CM-H2DCFDA probe and electron paramagnetic resonance; (iii) NO (nitrites and nitrates) production by Griess reaction; (iv) inflammation by ELISA assay; and (v) calcium signaling by confocal microscopy. The present study characterizes the in vitro model mimicking endothelial dysfunction in PH and indicates that, under such pathological conditions, oxidative stress and inflammation are increased along with calcium signaling alterations, as compared to the physiological conditions. Human exposure to carbon black NPs could produce greater deleterious effects in vulnerable patients suffering from cardiovascular diseases.
Subject(s)
Calcium Signaling/drug effects , Endothelial Cells/drug effects , Hypertension, Pulmonary/metabolism , Nanoparticles/toxicity , Oxidative Stress/drug effects , Pulmonary Artery/drug effects , Soot/toxicity , Cell Hypoxia , Cells, Cultured , Electron Spin Resonance Spectroscopy , Endothelial Cells/metabolism , Endothelial Cells/ultrastructure , Humans , Hypertension, Pulmonary/pathology , Inflammation Mediators/metabolism , Interleukin-6/metabolism , Microscopy, Confocal , Microscopy, Electron, Transmission , Nanoparticles/metabolism , Nitrates/metabolism , Nitrites/metabolism , Pulmonary Artery/metabolism , Pulmonary Artery/ultrastructure , Soot/metabolismABSTRACT
BACKGROUND: Late recurrences in postmenopausal women with hormone receptor-positive breast cancers remain an important challenge. Avoidance or delayed development of resistance represents the main objective in extended endocrine therapy (ET). In animal models, resistance was reversed with restoration of circulating estrogen levels during interruption of letrozole treatment. This phase III, randomized, open-label Study of Letrozole Extension (SOLE) studied the effect of extended intermittent letrozole treatment in comparison with continuous letrozole. In parallel, the SOLE estrogen substudy (SOLE-EST) analyzed the levels of estrogen during the interruption of treatment. PATIENTS AND METHODS: SOLE enrolled 4884 postmenopausal women with hormone receptor-positive, lymph node-positive, operable breast cancer between December 2007 and October 2012 and among them, 104 patients were enrolled in SOLE-EST. They must have undergone local treatment and have completed 4-6 years of adjuvant ET. Patients were randomized between continuous letrozole (2.5 mg/day orally for 5 years) and intermittent letrozole treatment (2.5 mg/day for 9 months followed by a 3-month interruption in years 1-4 and then 2.5 mg/day during all of year 5). RESULTS: Intention-to-treat population included 4851 women in SOLE (n = 2425 in the intermittent and n = 2426 in the continuous letrozole groups) and 103 women in SOLE-EST (n = 78 in the intermittent and n = 25 in the continuous letrozole groups). After a median follow-up of 84 months, 7-year disease-free survival (DFS) was 81.4% in the intermittent group and 81.5% in the continuous group (hazard ratio: 1.03, 95% confidence interval: 0.91-1.17). Reported adverse events were similar in both groups. Circulating estrogen recovery was demonstrated within 6 weeks after the stop of letrozole treatment. CONCLUSIONS: Extended adjuvant ET by intermittent administration of letrozole did not improve DFS compared with continuous use, despite the recovery of circulating estrogen levels. The similar DFS coupled with previously reported quality-of-life advantages suggest intermittent extended treatment is a valid option for patients who require or prefer a treatment interruption.
Subject(s)
Breast Neoplasms , Aromatase Inhibitors/therapeutic use , Breast Neoplasms/drug therapy , Chemotherapy, Adjuvant , Disease-Free Survival , Estrogens , Female , Humans , Letrozole , Nitriles/therapeutic use , Postmenopause , Receptors, Estrogen , Receptors, Progesterone , Tamoxifen/therapeutic use , Triazoles/therapeutic useABSTRACT
Automatic tracking of viral structures displayed as small spots in fluorescence microscopy images is an important task to determine quantitative information about cellular processes. We introduce a novel probabilistic approach for tracking multiple particles based on multi-sensor data fusion and Bayesian smoothing methods. The approach exploits multiple measurements as in a particle filter, both detection-based measurements and prediction-based measurements from a Kalman filter using probabilistic data association with elliptical sampling. Compared to previous probabilistic tracking methods, our approach exploits separate uncertainties for the detection-based and prediction-based measurements, and integrates them by a sequential multi-sensor data fusion method. In addition, information from both past and future time points is taken into account by a Bayesian smoothing method in conjunction with the covariance intersection algorithm for data fusion. Also, motion information based on displacements is used to improve correspondence finding. Our approach has been evaluated on data of the Particle Tracking Challenge and yielded state-of-the-art results or outperformed previous approaches. We also applied our approach to challenging time-lapse fluorescence microscopy data of human immunodeficiency virus type 1 and hepatitis C virus proteins acquired with different types of microscopes and spatial-temporal resolutions. It turned out, that our approach outperforms existing methods.
Subject(s)
Algorithms , Viral Structures , Bayes Theorem , Humans , Microscopy, FluorescenceABSTRACT
Skin sensitising substances that induce contact allergy and consequently risk elicitation of allergic contact dermatitis (ACD) remain an important focus regarding the replacement of animal experimentation. Current in vivo methods, notably the local lymph node assay (LLNA) refined and reduced animal usage and led to a marked improvement in hazard identification, characterisation and risk assessment. Since validation, regulatory confidence in the LLNA approach has evolved until it became the first choice assay in most regulated sectors. Currently, hazard identification using the LLNA is being actively replaced by a toolbox of non-animal approaches. However, there remains a need to increase confidence in the use of new approach methodologies (NAMs) as replacements for LLNA sensitiser potency estimation. The EPAA Partners Forum exchanged the current state of knowledge on use of NAMs in various industry sectors and regulatory environments. They then debated current challenges in this area and noted several ongoing needs. These included a requirement for reference standards for potency, better characterisation of applicability domains/technical limitations of NAMs, development of a framework for weight of evidence assessments, and an increased confidence in the characterisation of non-sensitisers. Finally, exploration of an industry/regulator cross-sector user-forum on skin sensitisation was recommended.
Subject(s)
Allergens/toxicity , Animal Testing Alternatives/standards , Congresses as Topic/standards , Local Lymph Node Assay , Research Report/standards , Skin/drug effects , Animal Testing Alternatives/methods , Animals , Belgium/epidemiology , Dermatitis, Allergic Contact/diagnosis , Dermatitis, Allergic Contact/epidemiology , Humans , Risk Assessment/methods , Risk Assessment/standardsABSTRACT
Dickkopf-1 (DKK1), a Wnt inhibitor secreted by bone marrow stromal cells (MSC), is known to play an important role in long-term non-union bone fracture defects and glucocorticoid induced osteoporosis. Mitigating its effects in early bone defects could improve osteogenesis and bone defect healing. Here, we applied a biomaterial strategy to deplete a defect environment from DKK1 by scavenging the protein via a macromer-based biomaterial covalently decorated with sulfated hyaluronan (sHA3). The material consisted of cross-copolymerized three-armed macromers with a small anchor molecule. Using the glycidyl anchor, polyetheramine (ED900) could be grafted to the material to which sHA3 was efficiently coupled in a separate step. For thorough investigation of material modification, flat material surfaces were generated by fabricating them on glass discs. The binding capability of sHA3 for DKK1 was demonstrated in this study by surface plasmon resonance measurements. Furthermore, the surfaces demonstrated the ability to scavenge and inactivate pathologic amounts of DKK1 from complex media. In a combinatory approach with Wnt3a, we were able to demonstrate that DKK1 is the preferred binding partner of our sHA3-functionalized surfaces. We validated our findings in a complex in vitro setting of differentiating SaOS-2 cells and primary hMSC. Here, endogenous DKK-1 was scavenged resulting in increased osteogenic differentiation indicating that this is a consistent biological effect irrespective of the model system used. Our study provides insights in the mechanisms and efficiency of sHA3 surface functionalization for DKK1 scavenging, which may be used in a clinical context in the future.
Subject(s)
Biocompatible Materials , Osteogenesis , Cell Differentiation , Hyaluronic Acid , SulfatesABSTRACT
Vortex-mediated magnetization reversal in individual ultra-small (â¼100 nm) ferromagnetic particles at low temperatures is studied by nanoSQUID magnetometry. At zero applied bias field, the flux-closure magnetic state (vortex) and the quasi uniform configuration are bi-stable. This stems from the extremely small size of the nanoparticles that lies very close to the limit of single-domain formation. The analysis of the temperature-dependent (from 0.3 to 70 K) hysteresis of the magnetization allows us to infer the nature of the ground state magnetization configuration. The latter corresponds to a vortex state as also confirmed by electron holography experiments. Based on the simultaneous analysis of the vortex nucleation and annihilation data, we estimate the magnitude of the energy barriers separating the quasi single-domain and the vortex state and their field dependence. For this purpose, we use a modified power-law scaling of the energy barriers as a function of the applied bias field. These studies are essential to test the thermal and temporal stability of flux-closure states stabilized in ultra-small ferromagnets.
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INTRODUCTION: The use of rotating-hinge total knee arthroplasties (TKA), despite several developments in prosthetic design, remains controversial. Results as well as indications of these devices are still discussed in primary intention and for young patients. The aim was to analyze early complications and survival rate of rotating-hinge TKA in primary intention and for revisions. METHODS: A retrospective study included all the patients operated for primary or revision TKA procedure using a rotating-hinge TKA between 2015 and 2018. Clinical and radiological data were collected before surgery and then at a minimum follow-up of 1 year. The primary endpoint was the aseptic revision-free survival rate. Secondary endpoints were the overall survival rate, IKS scores, range of motion and patellar complications. RESULTS: Forty patients were included at an average follow-up of 18 months. Primary implantation was performed for 12 patients (30%), and revision for 28 cases (70%). At a mean follow-up of 18 months, only one implant was removed for a septic cause. The cumulative survival rate at 24 months was 95%. At final review, eight knees (20%) had been revised, five (12.5%) due to infection, two (5%) because of extensor mechanism failure, two (5%) for global stiffness. The objective and subjective IKS were significantly higher postoperatively in both primary and revision groups (p < 0.0001). Patellar height was significantly smaller after revision (p = 0.04), while ROM significantly improved in this group (p = 0.02). At final endpoint, one implant was removed for a septic cause. CONCLUSION: This rotating-hinge TKA provides satisfying clinical and functional outcomes in primary intentions and in revision cases. There was no implant-associated complication. The complication rate remains high for revision surgery cases, mostly due to previous joint infections and poor soft tissue quality causing extensor mechanism failure. A longer-term study should be conducted to confirm this trend.
Subject(s)
Arthroplasty, Replacement, Knee , Arthroplasty, Replacement, Knee/adverse effects , Arthroplasty, Replacement, Knee/methods , Arthroplasty, Replacement, Knee/statistics & numerical data , Humans , Postoperative Complications/epidemiology , Reoperation/statistics & numerical data , Retrospective StudiesABSTRACT
In this review article, the authors describe all relevant aspects of the new S2k guideline from the German Society of Urology (Deutschen Gesellschaft für Urologie, DGU) for the diagnosis and treatment of IC/PBS (interstitial cystitis/painful bladder syndrome). A list of necessary and optional examinations and the necessity of diagnosis of exclusion are summarized and evaluated. The treatment options listed (ranging from conservative, oral drug, and complementary medicine to interventional surgical procedures) also give the reader a good overview of the contents of the guideline and possible therapeutic approaches. Finally, the recommendations including consensus of the guideline group are also summarized in various information boxes.
Subject(s)
Cystitis, Interstitial/diagnosis , Cystitis, Interstitial/therapy , Practice Guidelines as Topic , Urology/standards , Germany , Humans , Pain , Physical Examination , Societies, MedicalABSTRACT
In the last 20 years, alternative approaches to the identification of skin sensitisation hazards have been at the forefront of the 3Rs and have helped refine the validation and acceptance processes. However, experience with the local lymph node assay showed that, post-validation, challenges still occurred, particularly when a wider diversity of chemical substances was addressed, a situation which will arise with validated in vitro alternatives. In the present work, a range of substances potentially challenging to assess in current nonanimal OECD test guidelines were evaluated in several of the emerging in vitro alternatives. Twelve such substances (of which just over half were known skin sensitisers) were assessed in 4 assays, all based on reconstructed human epidermis (RHE) models. For hazard identification, the overall predictive accuracy ranged around 70% for three assays, although for one (SensCeeTox), it fell below 50% when human data was used as the benchmark. In most cases, sensitivity was high, such that sensitisation was overpredicted. As the substances were challenging to assess in other nonanimal methods, the results indicate that the 3D RHE models may be a useful tool for assessing skin sensitisation potentials without needing to revert to animal use.
Subject(s)
Animal Testing Alternatives , Biological Assay , Epidermis/drug effects , Haptens/toxicity , Epidermis/metabolism , Gene Expression Regulation/drug effects , Humans , In Vitro Techniques , Interleukin-18/metabolism , Skin Irritancy TestsABSTRACT
For bacterial genome sequencing, libraries from different strains are usually multiplexed in a single run. Normalized libraries are most often pooled in equal volumes, as recommended by next-generation sequencing platform manufacturers. This equal-volume strategy is well suited for multiplexing isolates from the same species. However, for runs involving multiple microbial species, an equimolar library pooling is more adapted because of the variation in bacterial genome size. To demonstrate its utility in clinical microbiology, we compared both equal-volume and equimolar strategies using a menu comprising 13 bacterial species involved in healthcare-associated infections. We show that equimolar pooling limits the retesting risk due to insufficient coverage depth, particularly when interspecies genome size difference is more than 2-fold. The use of this alternative strategy for multiplexing pathogenic bacteria should lead to more cost effective whole-genome sequencing applications in clinical microbiology.
Subject(s)
Bacteria/genetics , Genome, Bacterial/genetics , Bacteria/classification , Cross Infection/microbiology , DNA, Bacterial/genetics , Genome Size , High-Throughput Nucleotide Sequencing , Humans , Multiplex Polymerase Chain Reaction , Sequence Analysis, DNASubject(s)
Aromatic Amino Acid Decarboxylase Inhibitors/pharmacology , Benserazide/pharmacology , Dopamine Agents/pharmacology , Epilepsy, Temporal Lobe , Hyperkinesis , Levodopa/pharmacology , Movement Disorders , Phosphoric Diester Hydrolases/genetics , Aromatic Amino Acid Decarboxylase Inhibitors/administration & dosage , Benserazide/administration & dosage , Child , Consanguinity , Dopamine Agents/administration & dosage , Drug Combinations , Epilepsy, Temporal Lobe/drug therapy , Epilepsy, Temporal Lobe/genetics , Female , Humans , Hyperkinesis/drug therapy , Hyperkinesis/genetics , Infant , Levodopa/administration & dosage , Movement Disorders/drug therapy , Movement Disorders/genetics , Siblings , Exome SequencingABSTRACT
Genome editing represents a powerful tool to treat inherited disorders. Highly specific endonucleases induce a DNA double strand break near the mutant site, which is subsequently repaired by cellular DNA repair mechanisms that involve the presence of a wild type template DNA. In vivo applications of this strategy are still rare, in part due to the absence of appropriate animal models carrying human disease mutations and knowledge of the efficient targeting of endonucleases. Here we report the generation and characterization of a new mouse model for X-linked retinitis pigmentosa (XLRP) carrying a point mutation in the mutational hotspot exon ORF15 of the RPGR gene as well as a recognition site for the homing endonuclease I-SceI. Presence of the genomic modifications was verified at the RNA and protein levels. The mutant protein was observed at low levels. Optical coherence tomography studies revealed a slowly progressive retinal degeneration with photoreceptor loss starting at 9 months of age, paralleling the onset of functional deficits as seen in the electroretinogram. Early changes to the outer retinal bands can be used as biomarker during treatment applications. We further show for the first time efficient targeting using the I-SceI enzyme at the genomic locus in a proof of concept in photoreceptors following adeno-associated virus mediated gene transfer in vivo. Taken together, our studies not only provide a human-XLRP disease model but also act as a platform to design genome editing technology for retinal degenerative diseases using the currently available endonucleases.