Development of a Suite of Gadolinium-Free OATP1-Targeted Paramagnetic Probes for Liver MRI.

Five amphiphilic, anionic Mn(II) complexes were synthesized as contrast agents targeted to organic anion transporting polypeptide transporters (OATP) for liver magnetic resonance imaging (MRI). The Mn(II) complexes are synthesized in three steps, each from the commercially available trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (CDTA) chelator, with T1-relaxivity of complexes ranging between 2.3 and 3.0 mM-1 s-1 in phosphate buffered saline at an applied field strength of 3.0 T. Pharmacokinetics were assessed in female BALB/c mice by acquiring T1-weighted images dynamically for 70 min after agent administration and determining contrast enhancement and washout in various organs. Uptake of Mn(II) complexes in human OATPs was investigated through in vitro assays using MDA-MB-231 cells engineered to express either OATP1B1 or OATP1B3 isoforms. Our study introduces a new class of Mn-based OATP-targeted contrast that can be broadly tuned via simple synthetic protocols.

Visualizing cell-cell communication using synthetic notch activated MRI.

Cell-cell communication plays a fundamental role in multicellular organisms. Cell-based cancer immunotherapies rely on the ability of innate or engineered receptors on immune cells to engage specific antigens on cancer cells to induce tumor kill. To improve the development and translation of these therapies, imaging tools capable of noninvasively and spatiotemporally visualizing immune-cancer cell interactions would be highly valuable. Using the synthetic Notch (SynNotch) system, we engineered T cells that upon interaction with a chosen antigen (CD19) on neighboring cancer cells induce the expression of optical reporter genes and the human-derived, magnetic resonance imaging (MRI) reporter gene organic anion transporting polypeptide 1B3 (OATP1B3). Administration of engineered T cells induced the antigen-dependent expression of all our reporter genes in mice bearing CD19-positive tumors but not CD19-negative tumors. Notably, due to the high spatial resolution and tomographic nature of MRI, contrast-enhanced foci within CD19-positive tumors representing OATP1B3-expressing T cells were clearly visible and their distribution was readily mapped. We then extended this technology onto human natural killer-92 (NK-92) cells, observing similar CD19-dependent reporter activity in tumor-bearing mice. Furthermore, we show that when delivered intravenously, engineered NK-92 cells can be detected via bioluminescence imaging in a systemic cancer model. With continued work, this highly modular imaging strategy could aid in the monitoring of cell therapies in patients and, beyond this, augment our understanding of how different cell populations interact within the body during normal physiology or disease.

A Genetically Encoded Magnetic Resonance Imaging Reporter Enables Sensitive Detection and Tracking of Spontaneous Metastases in Deep Tissues.

Metastasis is the leading cause of cancer-related death. However, it remains a poorly understood aspect of cancer biology, and most preclinical cancer studies do not examine metastasis, focusing solely on the primary tumor. One major factor contributing to this paradox is a gap in available tools for accurate spatiotemporal measurements of metastatic spread in vivo. Here, our objective was to develop an imaging reporter system that offers sensitive three-dimensional (3D) detection of cancer cells at high resolutions in live mice. An organic anion-transporting polypeptide 1b3 (oatp1b3) was used as an MRI reporter gene, and its sensitivity was systematically optimized for in vivo tracking of viable cancer cells in a spontaneous metastasis model. Metastases with oatp1b3-MRI could be observed at the single lymph node level and tracked over time as cancer cells spread to multiple lymph nodes and different organ systems in individual animals. While initial single lesions were successfully imaged in parallel via bioluminescence, later metastases were largely obscured by light scatter from the initial node. Importantly, MRI could detect micrometastases in lung tissue comprised on the order of 1,000 cancer cells. In summary, oatp1b3-MRI enables longitudinal tracking of cancer cells with combined high resolution and high sensitivity that provides 3D spatial information and the surrounding anatomical context. SIGNIFICANCE: An MRI reporter gene system optimized for tracking metastasis in deep tissues at high resolutions and able to detect spontaneous micrometastases in lungs of mice provides a useful tool for metastasis research.

Gadolinium-free Magnetic Resonance Imaging of the Liver via an Oatp1-Targeted Manganese(III) Porphyrin.

Controversy surrounding gadolinium-based contrast agents (GBCAs) has rendered their continued utility highly contentious, but the liver-specific GBCA Gd(III) ethoxybenzyl-diethylene triamine pentaacetic acid (Gd(III)-EOB-DTPA) remains in use because it provides unique diagnostic information that could not be obtained by any other means. To address the need for an alternate liver-specific MRI probe, we synthesized Mn(III) 20-(4-ethoxyphenyl) porphyrin-5,10,15-tricarboxylate (Mn(III)TriCP-PhOEt), which exhibited significantly higher r1 relaxivity than Gd(III)-EOB-DTPA in vitro, while also targeting hepatocyte-specific organic anion-transporting polypeptide 1 (Oatp1) channels as a marker of viability. In mice, Mn(III)TriCP-PhOEt resulted in significant and specific increases in liver signal intensity on T1-weighted images and significant decreases in liver T1 time relative to pre-contrast measurements. Our findings suggest that Mn(III)TriCP-PhOEt operates as a specific and sensitive MR probe for Oatp1-targeted imaging in vivo.

Safe harbor-targeted CRISPR-Cas9 homology-independent targeted integration for multimodality reporter gene-based cell tracking.

Imaging reporter genes provides longitudinal information on the biodistribution, growth, and survival of engineered cells in vivo. A translational bottleneck to using reporter genes is the necessity to engineer cells with randomly integrating vectors. Here, we built homology-independent targeted integration (HITI) CRISPR-Cas9 minicircle donors for precise safe harbor-targeted knock-in of fluorescence, bioluminescence, and MRI (Oatp1a1) reporter genes. Our results showed greater knock-in efficiency using HITI vectors compared to homology-directed repair vectors. HITI clones demonstrated functional fluorescence and bioluminescence reporter activity as well as significant Oatp1a1-mediated uptake of the clinically approved MRI agent gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid. Contrast-enhanced MRI improved the conspicuity of both subcutaneous and metastatic Oatp1a1-expressing tumors before they became palpable or even readily visible on precontrast images. Our work demonstrates the first CRISPR-Cas9 HITI system for knock-in of large DNA donor constructs at a safe harbor locus, enabling multimodal longitudinal in vivo imaging of cells.

Gellan gum-based gels with tunable relaxation properties for MRI phantoms.

OBJECT: The research follows the analysis of gellan gum-based gels as novel MRI phantom material with the implementation of a design of experiments model to obtain tunable relaxation properties. MATERIALS AND METHODS: Gellan gum gels doped with newly synthesized superparamagnetic iron oxide nanoparticles (SPIONs) and either MnCl2 or GdCl3 were prepared and scanned from 230 µT to 3 T. Nineteen gel samples were formulated with varying concentrations of contrast agents to determine the linear, quadratic, and interactive effects of the contrast agents by a central composite design of experiment. To inhibit microbial growth in the gels and to enable long-term use, methyl 4­hydroxybenzoate (methylparaben) was utilized. RESULTS: The model containing SPIONs and metal salts relaxivity was analyzed with ANOVA, and the resulting significant coefficients were tabulated. The mathematical model was able to accurately predict the intended relaxation property from the concentration of the contrast agent with adjusted R2 values > 0.97 for longitudinal (R1) relaxation rates and 0.87 for transverse (R2) relaxation rates. CONCLUSION: The gel material maintained physical, chemical, and biological stability for at least four months and contained controllable relaxation properties while maintaining optical clarity.

Dermatitis Artefacta in Childhood: A Retrospective Analysis of 44 Patients, 1976-2006.

BACKGROUND: Dermatitis artefacta (DA) consists of self-inflicted skin lesions that the patient denies having produced. OBJECTIVES: To conduct a single-center retrospective clinical review of children and adolescents diagnosed with DA. METHODS: From 1976 to 2006, data were collected on children diagnosed with DA who were seen in the Department of Dermatology in our hospital. Clinical and epidemiologic features are described. Forty-four children (mean age 12.9 yrs) were selected, representing 21.9% of the total patients with DA recorded (n = 201) during this period. RESULTS: The most frequent clinical forms were excoriations (16 [36.4%]) and ulcers (10 [22.7%]), followed by blisters (7 [15.9%]), burns (3 [6.8%]), contact dermatitis (3 [6.8%]), hematomas (2 [4.5%]), panniculitis (1 [2.3%]), cheilitis (1 [2.3%]), and hyperpigmentation (1 [2.3%]). Sixteen were located exclusively on the face and neck, whereas 28 also had other locations (upper limbs, n = 10; lower limbs, n = 9; thorax, n = 5; abdomen, n = 4). Cutaneous lesions were treated with occlusive bandages using zinc paste or a plaster splint when necessary. CONCLUSION: To our knowledge, this is the largest reported series of DA in childhood. This complicated psychodermatologic condition requires correct diagnosis, appropriate management, and psychiatric assessment.

O to Z flaps in facial reconstructions.

Local flaps are the standard procedure to reconstruct facial defects. As it occurs in any surgical procedure, the incision should be planned so that scars are located in the minimum skin tension lines. We report two cases of O to Z flaps in the supra and infraciliary regions. One of them is a hatchet flap.

O to Z flaps in facial reconstructions

Local flaps are the standard procedure to reconstruct facial defects. As it occurs in any surgical procedure, the incision should be planned so that scars are located in the minimum skin tension lines. We report two cases of O to Z flaps in the supra and infraciliary regions. One of them is a hatchet flap.

Superficial Acral Fibromyxoma involving the nail's apparatus. Case report and literature review.

Superficial Acral Fibromyxoma is a rare tumor of soft tissues. It is a relatively new entity described in 2001 by Fetsch et al. It probably represents a fibrohistiocytic tumor with less than 170 described cases. We bring a new case of SAF on the 5th toe of the right foot, in a 43-year-old woman. After surgical excision with safety margins which included the nail apparatus, it has not recurred (22 months of follow up). We carried out a review of the location of all SAF published up to the present day.

Superficial Acral Fibromyxoma involving the nail's apparatus. Case report and literature review

Superficial Acral Fibromyxoma is a rare tumor of soft tissues. It is a relatively new entity described in 2001 by Fetsch et al. It probably represents a fibrohistiocytic tumor with less than 170 described cases. We bring a new case of SAF on the 5th toe of the right foot, in a 43-year-old woman. After surgical excision with safety margins which included the nail apparatus, it has not recurred (22 months of follow up). We carried out a review of the location of all SAF published up to the present day.

Undesirable effects after treatment with dermal fillers.

BACKGROUND: Soft tissue augmentation is one of the most frequent techniques in cosmetic dermatology. Nowadays, there are a high number of available materials. Nonanimal hyaluronic acid (HA) is one of most useful fillers for lip augmentation and for treating nasolabial folds, marionette lines, and the dynamic wrinkles of the upper face. OBJECTIVE: To evaluate the type and management of undesirable effects of nonanimal reticulated or stabilized HA observed in our cosmetic unit in the past 3 years. MATERIALS AND METHODS: The consecutive patients using HA attending to our clinic in the past 3 years were divided into 3 categories, according to the time of presentation of the adverse reactions: immediate, early, and late-onset complications. All patients were treated. RESULTS: Twenty-three patients presented to our clinic complaining of complications after soft tissue augmentation with HA. Ten patients presented immediate-onset complications, 8 showed early-onset complications, and 5 cases complaint of late-onset complications. Treatment of the first group consisted of hyaluronidase injection, massage, and topical antibiotics. Early- and late-onset complications were treated with intralesional triamcinolone acetonide. All patients improved, with the exception of a woman with recurrent granulomas. CONCLUSION: Generally, undesirable effects of HA (immediate, early, or late onset) are not frequent, and when present, they improve if treated properly. Physicians need to be aware of these possible adverse events in order to establish proper treatment and prevent scarring or other sequelae.

Perifollicular erythema as a trichoscopy sign of progression in frontal fibrosing alopecia.

INTRODUCTION: Frontal fibrosing alopecia (FFA) in an entity characterized by the recession of the frontotemporal hairline (FTHL) with alopecic scarring change. In recent years there are numerous articles discussing the usefulness of dermoscopy for the clinical diagnosis of different types of scarring alopecia. MATERIALS AND METHODS: We value 79 patients diagnosed with FFA, evaluating some trichoscopical findings described as typical for FFA: Absence of follicular opening, follicular hyperkeratosis, follicular plugs and erythema. RESULTS: In a population of 79 women, 100% showed no follicular opening, 72.1% follicular hyperkeratosis, 66.3% perifollicular erythema and 44.8% follicular plugs. Thus, 100% of patients had at least one of the dermoscopic elements described as suggestive of FFA, 53% two of them, 45% three and 27%, all those elements. Perifollicular erythema was present in 95% of cases in which the disease was active. CONCLUSIONS: We consider that the presence of perifollicular erythema will be a direct marker of FFA activity.

Tuberculosis: an unusual cause of genital ulcer.

Tuberculosis can cause genital ulcers, although this clinical manifestation was more frequent at the beginning of the 20th century as it was related to the rite of circumcision. We report the case of a patient with this disease, presumably acquired through sexual intercourse.