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1.
Cancer Immunol Immunother ; 73(9): 161, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38954006

RESUMEN

BACKGROUND: Although nivolumab prolongs overall survival (OS) in pretreated patients with metastatic renal cell carcinoma (mRCC), underlining clinical and biological features of long-term responses are still to be determined. This study aims to investigate clinical and pathological characteristics of mRCC patients who achieved long-term responses during nivolumab treatment. MATERIALS AND METHODS: A retrospective analysis was performed on mRCC patients receiving nivolumab as second or further therapy line between May 2016 and January 2019 in 34 Italian Oncology Centres. Outcome assessments and logistic regression were performed to evaluate factors influencing long-term responses. RESULTS: A total of 571 patients with a median age of 61 years (range 17-85) were included in the analysis. With a median follow-up of 22.1 (1.0-89.0) months, 23.1% of patients were 2-year progression-free on treatment with nivolumab, hence they were categorized as long-term responders. Baseline characteristics, including age, gender, and histology, were similar between long- and short-term responders. Karnofsky Performance Status ≥ 80% was significantly associated with long-term response (p = 0.02), while bone metastases (p = 0.03), International mRCC Database Consortium intermediate-poor risk (p < 0.01) and Neutrophil-to-Lymphocyte Ratio ≥ 3.2 (p = 0.02) were associate with short-term responses. Long-term responders exhibited a median progression-free survival of 55.0 months versus 4.0 months of the short-term responders. The median OS was not reached in long-term responders while it was 17.0 months for short*term responders. CONCLUSION: This retrospective analysis sheds light on factors associated with long-term response to nivolumab in mRCC. Understanding these clinical features will be essential for selecting patients who may mostly benefit from immunotherapy.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Nivolumab , Humanos , Nivolumab/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/mortalidad , Carcinoma de Células Renales/patología , Femenino , Masculino , Persona de Mediana Edad , Anciano , Adulto , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/mortalidad , Neoplasias Renales/patología , Estudios Retrospectivos , Anciano de 80 o más Años , Adulto Joven , Adolescente , Antineoplásicos Inmunológicos/uso terapéutico , Estudios de Seguimiento
2.
Proc Natl Acad Sci U S A ; 118(9)2021 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-33622793

RESUMEN

Reactive oxygen species (ROS) like hydrogen peroxide (H2O2) are transient species that have broad actions in signaling and stress, but spatioanatomical understanding of their biology remains insufficient. Here, we report a tandem activity-based sensing and labeling strategy for H2O2 imaging that enables capture and permanent recording of localized H2O2 fluxes. Peroxy Green-1 Fluoromethyl (PG1-FM) is a diffusible small-molecule probe that senses H2O2 by a boronate oxidation reaction to trigger dual release and covalent labeling of a fluorescent product, thus preserving spatial information on local H2O2 changes. This unique reagent enables visualization of transcellular redox signaling in a microglia-neuron coculture cell model, where selective activation of microglia for ROS production increases H2O2 in nearby neurons. In addition to identifying ROS-mediated cell-to-cell communication, this work provides a starting point for the design of chemical probes that can achieve high spatial fidelity by combining activity-based sensing and labeling strategies.


Asunto(s)
Colorantes Fluorescentes/metabolismo , Peróxido de Hidrógeno/metabolismo , Microglía/metabolismo , Sondas Moleculares/metabolismo , Neuronas/metabolismo , Transducción de Señal/fisiología , Animales , Ácidos Borónicos/química , Comunicación Celular , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Técnicas de Cocultivo , Embrión de Mamíferos , Colorantes Fluorescentes/síntesis química , Células HeLa , Humanos , Ratones , Microglía/citología , Microglía/efectos de los fármacos , Sondas Moleculares/síntesis química , Neuronas/citología , Neuronas/efectos de los fármacos , Oxidación-Reducción , Paraquat/farmacología , Células RAW 264.7 , Coloración y Etiquetado/métodos
3.
J Transl Med ; 20(1): 435, 2022 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-36180954

RESUMEN

BACKGROUND: Nephrectomy is considered the backbone of managing patients with localized and selected metastatic renal cell carcinoma (mRCC). The prognostic role of nephrectomy has been widely investigated with cytokines and targeted therapy, but it is still unclear in the immunotherapy era. METHODS: We investigated the Meet-URO-15 study dataset of 571 pretreated mRCC patients receiving nivolumab as second or further lines about the prognostic role of the previous nephrectomy (received in either the localized or metastatic setting) in the overall population and according to the Meet-URO score groups. RESULTS: Patients who underwent nephrectomy showed a significantly reduced risk of death (HR 0.44, 95% CI 0.32-0.60, p < 0.001) with a longer median overall survival (OS) (35.9 months vs 12.1 months), 1-year OS of 71.6% vs 50.5% and 2-years OS of 56.5% vs 22.0% compared to those who did not. No significant interaction between nephrectomy and the overall five Meet-URO score risk groups was observed (p = 0.17). It was statistically significant when merging group 1 with 2 and 3 and group 4 with 5 (p = 0.038) and associated with a longer OS for the first three prognostic groups (p < 0.001), but not for groups 4 and 5 (p = 0.54). CONCLUSIONS: Our study suggests an overall positive impact of the previous nephrectomy on the outcome of pretreated mRCC patients receiving immunotherapy. The clinical relevance of cytoreductive nephrectomy, optimal timing and patient selection deserves further investigation, especially for patients with Meet-URO scores of 1 to 3, who are the once deriving benefit in our analyses. However, that benefit is not evident for IMDC poor-risk patients (including the Meet-URO score groups 4 and 5) and a subgroup of IMDC intermediate-risk patients defined as group 4 by the Meet-URO score.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/cirugía , Citocinas , Humanos , Inmunoterapia , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/cirugía , Nefrectomía , Nivolumab/uso terapéutico , Pronóstico , Estudios Retrospectivos
4.
Bioconjug Chem ; 33(8): 1536-1542, 2022 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-35939764

RESUMEN

Bioconjugation techniques for biomolecule-polymer conjugation are numerous; however, slow kinetics and steric challenges generally necessitate excess reagents or long reaction times. Organometallic transformations are known to circumvent these issues; yet, harsh reaction conditions, incompatibility in aqueous media, and substrate promiscuity often limit their use in a biological context. The work reported herein demonstrates a facile and benign organometallic Au(III) S-arylation approach that enables the synthesis of poly(ethylene glycol) monomethyl ether (mPEG)-protein conjugates with high efficiency. Isolable and bench-stable 2, 5, and 10 kDa mPEG-Au(III) reagents were synthesized via oxidative addition into terminal aryl iodide substituents installed on mPEG substrates with a (Me-DalPhos)Au(I)Cl precursor. Reaction of the isolable mPEG-Au(III) oxidative addition complexes with a cysteine thiol on a biomolecule resulted in facile and selective cysteine arylation chemistry, forging covalent S-aryl linkages and affording the mPEG-biomolecule conjugates. Notably, low polymer reagent loadings were used to achieve near quantitative conversion at room temperature in 1 min due to the rapid kinetics and high chemoselectivity of this Au-based bioconjugation approach. Therefore, this work represents an important addition to the protein-polymer conjugation chemical toolbox.


Asunto(s)
Cisteína , Polietilenglicoles , Cisteína/química , Indicadores y Reactivos , Oxidación-Reducción , Polietilenglicoles/química , Proteínas/química
5.
Prog Polym Sci ; 1002020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32863465

RESUMEN

Biomolecule-polymer conjugates are constructs that take advantage of the functional or otherwise beneficial traits inherent to biomolecules and combine them with synthetic polymers possessing specially tailored properties. The rapid development of novel biomolecule-polymer conjugates based on proteins, peptides, or nucleic acids has ushered in a variety of unique materials, which exhibit functional attributes including thermo-responsiveness, exceptional stability, and specialized specificity. Key to the synthesis of new biomolecule-polymer hybrids is the use of controlled polymerization techniques coupled with either grafting-from, grafting-to, or grafting-through methodology, each of which exhibit distinct advantages and/or disadvantages. In this review, we present recent progress in the development of biomolecule-polymer conjugates with a focus on works that have detailed the use of grafting-from methods employing ATRP, RAFT, or ROMP.

6.
Int Ophthalmol ; 40(1): 205-212, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31571089

RESUMEN

PURPOSE: To evaluate efficacy of a microemulsion of fatty acids of the ω-3 series on the regeneration of the sub-epithelial corneal nerve plexus in patients with keratoconus after epi-off cross-linking. METHODS: In this prospective study, we recruited 40 patients, 18 females, mean age 28 years (range 22-37), who were randomly divided in two groups. Group A, 20 patients, after cross-linking were treated with a microemulsion of fatty acids of the ω-3 series. Group B were treated with hyaluronic acid (0.15%)-based tear substitute. Nerve tortuosity, reflectivity and density were examined with in vivo confocal microscopy. Ocular surface disease index (OSDI) questionnaire at the preoperative and at each follow-up visit (1, 3 and 6 months) after treatment was completed. RESULTS: No significant difference between the two groups was noted at 1 month in terms of nerve density and OSDI. A statistically significant difference between the two groups was detected at 3 months in terms of nerve fibers density (6 ± 0.82 in Group A and 1 ± 0.51 in Group B, P = 0.0001). Reflectivity and tortuosity of the fibers did not show significant differences between the two groups at any time point. At 1 month, OSDI average value in group A and in group B was 31.5 ± 1.94 and 30 ± 1.96, at 3 months 13 ± 1.71 and 28 ± 1.83, and at 6 months 10.5 ± 1.87 and 9.0 ± 1.81, respectively. CONCLUSION: The use of a microemulsion of fatty acids appears to ensure a faster regeneration of nerve fibers in patients undergoing epi-off cross-linking.


Asunto(s)
Colágeno/uso terapéutico , Reactivos de Enlaces Cruzados/uso terapéutico , Epitelio Corneal/inervación , Ácidos Grasos/administración & dosificación , Queratocono/tratamiento farmacológico , Regeneración Nerviosa/efectos de los fármacos , Fotoquimioterapia/métodos , Administración Tópica , Adulto , Emulsiones/administración & dosificación , Epitelio Corneal/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Queratocono/diagnóstico , Masculino , Microscopía Confocal , Fibras Nerviosas/patología , Fármacos Fotosensibilizantes/uso terapéutico , Estudios Prospectivos , Riboflavina/uso terapéutico , Resultado del Tratamiento , Rayos Ultravioleta , Adulto Joven
7.
Bioconjug Chem ; 30(10): 2594-2603, 2019 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-31498600

RESUMEN

Multivalent protein-protein interactions serve central roles in many essential biological processes, ranging from cell signaling and adhesion to pathogen recognition. Uncovering the rules that govern these intricate interactions is important not only to basic biology and chemistry but also to the applied sciences where researchers are interested in developing molecules to promote or inhibit these interactions. Here we report the synthesis and application of atomically precise inorganic cluster nanomolecules consisting of an inorganic core and a covalently linked densely packed layer of saccharides. These hybrid agents are stable under biologically relevant conditions and exhibit multivalent binding capabilities, which enable us to study the complex interactions between glycosylated structures and a dendritic cell lectin receptor. Importantly, we find that subtle changes in the molecular structure lead to significant differences in the nanomolecule's protein-binding properties. Furthermore, we demonstrate an example of using these hybrid nanomolecules to effectively inhibit protein-protein interactions in a human cell line. Ultimately, this work reveals an intricate interplay between the structural design of multivalent agents and their biological activities toward protein surfaces.


Asunto(s)
Nanoestructuras/química , Adhesión Celular/efectos de los fármacos , Moléculas de Adhesión Celular/química , Moléculas de Adhesión Celular/metabolismo , Ingeniería , Proteína gp120 de Envoltorio del VIH/química , Proteína gp120 de Envoltorio del VIH/metabolismo , Lectinas Tipo C/química , Lectinas Tipo C/metabolismo , Simulación de Dinámica Molecular , Unión Proteica/efectos de los fármacos , Conformación Proteica , Receptores de Superficie Celular/química , Receptores de Superficie Celular/metabolismo , Transducción de Señal/efectos de los fármacos
8.
Inorg Chem ; 58(16): 10516-10526, 2019 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-31247818

RESUMEN

Redox-active proanions of the type B12(OCH2Ar)12 [Ar = C6F5 (1), 4-CF3C6H4 (2), 3,5-(CF3)2C6H3 (3)] are introduced in the context of an experimental and computational study of the visible-light-initiated polymerization of a family of styrenes. Neutral, air-stable proanions 1-3 were found to initiate styrene polymerization through single-electron oxidation under blue-light irradiation, resulting in polymers with number-average molecular weights (Mn) ranging from ∼6 to 100 kDa. Shorter polymer products were observed in the majority of experiments, except in the case of monomers containing 4-X (X = F, Cl, Br) substituents on the styrene monomer when polymerized in the presence of 1 in CH2Cl2. Only under these specific conditions are longer polymers (>100 kDa) observed, strongly supporting the formulation that reaction conditions significantly modulate the degree of ion pairing between the dodecaborate anion and cationic chain end. This also suggests that 1-3 behave as weakly coordinating anions (WCA) upon one-electron reduction because no incorporation of the cluster-based photoinitiators is observed in the polymeric products analyzed. Overall, this work is a conceptual realization of a single reagent that can serve as a strong photooxidant, subsequently forming a WCA.

9.
Int Ophthalmol ; 39(3): 693-696, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29549486

RESUMEN

PURPOSE: To evaluate the effect of once daily administration of chitosan-N-acetylcysteine (Lacrimera®) in the management of dry eye disease (DED). METHODS: Eighteen patients (3 male, 15 female) aged 25-86 years (mean 61.1) and suffering from moderate to severe DED with superficial punctate keratitis (SPK) were retrospectively evaluated after a trial of Lacrimera® drops (1 drop in the morning for 5 days only). All the patients were using other artificial tears before the treatment. All lubricants were stopped, and Lacrimera® was started instead. Slit-lamp examination and images were taken before and at 1 and 3 weeks follow-up after the treatment. The subjective (Ocular Surface Disease Index, OSDI) and objective (Oxford Grading System, OGS) evaluation was recorded. A paired student's t test was performed to analyse the data. RESULTS: At baseline, the SPK grade was I to IV (OGS) and the OSDI ranged from 25 to 71.4. Fifteen patients showed a statistically significant (p < 0.0001) improvement in OGS and the OSDI at 3 weeks post-treatment. Three patients showed no improvement. CONCLUSIONS: A single-dose instillation of chitosan-N-acetylcysteine for five consecutive days improved signs and symptoms in patients affected from DED from a variety of causes, who were refractory to standard treatment with lubricants. Given its posology, the absence of side effects and the results obtained Lacrimera® should be taken into consideration as a viable option in patients with moderate to severe DED.


Asunto(s)
Acetilcisteína/administración & dosificación , Quitosano/análogos & derivados , Síndromes de Ojo Seco/tratamiento farmacológico , Queratitis/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Quitosano/administración & dosificación , Síndromes de Ojo Seco/diagnóstico , Síndromes de Ojo Seco/etiología , Femenino , Estudios de Seguimiento , Humanos , Queratitis/diagnóstico , Queratitis/tratamiento farmacológico , Gotas Lubricantes para Ojos , Masculino , Persona de Mediana Edad , Soluciones Oftálmicas , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
10.
J Am Chem Soc ; 140(23): 7065-7069, 2018 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-29790740

RESUMEN

An efficient method for chemoselective cysteine arylation of unprotected peptides and proteins using Au(III) organometallic complexes is reported. The bioconjugation reactions proceed rapidly (<5 min) at ambient temperature in various buffers and within a wide pH range (0.5-14). This approach provides access to a diverse array of S-aryl bioconjugates including fluorescent dye, complex drug molecule, affinity label, poly(ethylene glycol) tags, and a stapled peptide. A library of Au(III) arylation reagents can be prepared as air-stable, crystalline solids in one step from commercial reagents. The selective and efficient arylation procedures presented in this work broaden the synthetic scope of cysteine bioconjugation and serve as promising routes for the modification of complex biomolecules.


Asunto(s)
Complejos de Coordinación/química , Cisteína/análogos & derivados , Oro/química , Compuestos Orgánicos de Oro/química , Complejos de Coordinación/síntesis química , Cisteína/síntesis química , Glutatión/química , Concentración de Iones de Hidrógeno , Fenómenos Químicos Orgánicos , Compuestos Orgánicos de Oro/síntesis química , Oxidación-Reducción
11.
Breast Cancer Res Treat ; 172(1): 9-21, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30054831

RESUMEN

PURPOSE: Combining CDK4/6 inhibitors and endocrine therapy (ET) improved outcomes for the treatment of metastatic HR+/HER2- breast cancers. Here, we performed a meta-analysis of randomized clinical trials (RCTs) to better define the benefit and the risk of CDK4/6 inhibitors plus ET for endocrine-sensitive or endocrine-resistant population in metastatic HR+/HER2- breast cancer. METHOD: A systematic literature search of Pubmed, Embase, and the Cochrane Library was carried out up to 30 June 2018. Hazard ratios (HRs) and 95% confidence intervals (CIs) for progression-free survival (PFS), as well as odds ratios (ORs) for objective response rates, ≥ G3-G4 adverse events (AEs), and G3-G4 neutropenia were calculated for each trial. A meta-analysis was carried out using the random-effects model. RESULTS: Eight RCTs were eligible including 4578 breast cancer patients. Adding CDK4/6 inhibitors to ET in endocrine-sensitive (HR 0.55, 95% CI 0.50-0.62) or endocrine-resistant setting (HR 0.51, 95% CI 0.43-0.61) significantly improved the PFS of metastatic HR+/HER2- breast cancers regardless of menopausal status and site of metastasis. Moreover, CDK4/6 inhibitors plus ET meaningfully improved objective response rate in endocrine-sensitive (ORs 0.62, 95% CI 0.52-0.73) or endocrine-resistant setting (ORs 0.33, 95% CI 0.24-0.47). The use of these drugs was characterized by a significant increase of G3-G4 AEs (OR 10.88, 95% CI 6.53-18.14). CONCLUSION: Emerging data provide a new standard treatment for advanced HR+/HER2- breast cancer, regardless of menopausal status, prior hormonal/chemotherapy treatments delivered, sites of metastasis. However, benefits should be balanced with longer treatment duration, toxicities, and costs.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/uso terapéutico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Quinasa 4 Dependiente de la Ciclina/genética , Quinasa 6 Dependiente de la Ciclina/genética , Femenino , Humanos , Metástasis de la Neoplasia , Supervivencia sin Progresión , Ensayos Clínicos Controlados Aleatorios como Asunto , Receptor ErbB-2/genética , Receptores de Estrógenos/genética , Receptores de Progesterona/genética
12.
Sensors (Basel) ; 18(1)2018 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-29351221

RESUMEN

This work focuses on the proof-mass mechanical structural design improvement of a tri-axial piezoresistive accelerometer specifically designed for head injuries monitoring where medium-G impacts are common; for example, in sports such as racing cars or American Football. The device requires the highest sensitivity achievable with a single proof-mass approach, and a very low error (<1%) as the accuracy for these types of applications is paramount. The optimization method differs from previous work as it is based on the progressive increment of the sensor proof-mass mass moment of inertia (MMI) in all three axes. Three different designs are presented in this study, where at each step of design evolution, the MMI of the sensor proof-mass gradually increases in all axes. The work numerically demonstrates that an increment of MMI determines an increment of device sensitivity with a simultaneous reduction of cross-axis sensitivity in the particular axis under study. This is due to the linkage between the external applied stress and the distribution of mass (of the proof-mass), and therefore of its mass moment of inertia. Progressively concentrating the mass on the axes where the piezoresistors are located (i.e., x- and y-axis) by increasing the MMI in the x- and y-axis, will undoubtedly increase the longitudinal stresses applied in that areas for a given external acceleration, therefore increasing the piezoresistors fractional resistance change and eventually positively affecting the sensor sensitivity. The final device shows a sensitivity increase of about 80% in the z-axis and a reduction of cross-axis sensitivity of 18% respect to state-of-art sensors available in the literature from a previous work of the authors. Sensor design, modelling, and optimization are presented, concluding the work with results, discussion, and conclusion.


Asunto(s)
Sistemas Microelectromecánicos , Aceleración , Acelerometría , Traumatismos Craneocerebrales , Diseño de Equipo , Humanos
13.
Minim Invasive Ther Allied Technol ; 27(4): 217-220, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29214888

RESUMEN

BACKGROUND AND AIMS: Gallbladder carcinoma is a rare but aggressive malignant neoplasm. The incidence of intra- or post-operative incidental gallbladder carcinoma diagnosis following laparoscopic cholecystectomy is estimated to be 1-2%. Aggressive re-resection is warranted as the majority of patients have residual disease either in the liver or the lymph nodes. However the use of a minimally invasive surgical approach (MISA) to perform a radicalization in these patients has not been investigated yet. We retrospectively analyzed surgical and oncologic outcome of a small selected cohort of patients with incidental gallbladder carcinoma whom underwent redo radicalization surgery by MISA. MATERIAL AND METHODS: From April 2012 to June 2014 at our department six patients (three females and three males) with incidental findings of gallbladder carcinoma pT1b (stage I) following laparoscopic cholecystectomy, and referred to our center from other secondary-level referral hospitals, underwent a redo surgery for radicalization by means of laparoscopic (n. 3) or robotic approach (n. 3). A retrospective analysis of prospective collected data was performed. RESULTS: The redo procedure consisted of a liver resection (segments IVb + V) and lymph nodes clearance of hepatoduodenal hilum and common hepatic artery. Conversion rate was zero. Median operative time was 290 (250-310) min. Estimate blood loss was 175 (100-350) ml. Total hospital stay was 6 (5-10) days. All liver resections were performed without inflow vascular clamping. One patient was re-operated for hemoperitoneum while peri-operative mortality was zero. Oncologically, an R0 resection was always achieved with a mean number of lymph nodes retrieved of 17,5 (14-22). The stage of the neoplasm was confirmed in all cases but one, who was found to have a pN1 status (stage IIIb). At 21 (6-32) months follow-up all patients are alive and no recurrence has been observed. CONCLUSIONS: Our data suggest that radicalization of patients with stage I incidental postoperative gallbladder carcinoma can be done by a MISA without compromising the oncologic outcome. Larger studies are needed to validate these results.


Asunto(s)
Colecistectomía Laparoscópica/métodos , Neoplasias de la Vesícula Biliar/cirugía , Procedimientos Quirúrgicos Robotizados/métodos , Pérdida de Sangre Quirúrgica , Femenino , Humanos , Tiempo de Internación , Masculino , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Tempo Operativo , Reoperación , Estudios Retrospectivos
14.
Int Ophthalmol ; 38(5): 2211-2217, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28900769

RESUMEN

PURPOSE: To report for the first time a case of interface Scopulariopsis gracilis fungal keratitis following Descemet's stripping automated endothelial keratoplasty (DSAEK) with a contaminated graft. METHODS: A 57-year-old man with bilateral keratoconus and previous bilateral penetrating keratoplasties (PK) developed graft failure in association with marked corneal ectasia. He underwent a successful DSAEK. Unfortunately, a contaminated graft was transplanted and the following morning we were contacted by the eye bank to inform us a slow-growing fungus had been detected in the culture plates inoculated with dextran solution used to store the issued corneoscleral button. Immediate patient review revealed four infiltrates in the interface between the donor and the recipient tissue. The patient returned to theatre for the removal of the infected graft and was successfully treated with topical amphotericin 0.15%, voriconazole 1% and oral voriconazole and later oral itraconazole. Two intracameral injections of 5 µg in 0.1 ml of amphotericin B were also performed. RESULTS: A reference laboratory cultured and identified the fungus as Scopulariopsis gracilis species. The patient responded to treatment and eventually achieved a spectacle-corrected logMAR visual acuity of 0.3 following a delayed PK. CONCLUSION: Scopulariopsis gracilis fungal keratitis is a rare infection, and the species can be difficult to eradicate. This is the first case report of an infection secondary to a contaminated graft with the species, and we report its successful treatment with an excellent visual outcome.


Asunto(s)
Queratoplastia Endotelial de la Lámina Limitante Posterior/efectos adversos , Endotelio Corneal/trasplante , Infecciones Fúngicas del Ojo/etiología , Queratitis/etiología , Micosis/etiología , Scopulariopsis/aislamiento & purificación , Infección de la Herida Quirúrgica/etiología , Endotelio Corneal/microbiología , Infecciones Fúngicas del Ojo/diagnóstico , Infecciones Fúngicas del Ojo/microbiología , Supervivencia de Injerto , Humanos , Queratitis/diagnóstico , Queratitis/microbiología , Masculino , Persona de Mediana Edad , Micosis/diagnóstico , Micosis/microbiología , Infección de la Herida Quirúrgica/diagnóstico , Infección de la Herida Quirúrgica/microbiología , Donantes de Tejidos
15.
J Am Chem Soc ; 139(23): 7729-7732, 2017 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-28541671

RESUMEN

We report the first observed Pd-catalyzed isomerization ("cage-walking") of B(9)-bromo-meta-carborane during Pd-catalyzed cross-coupling, which enables the formation of B-O and B-N bonds at all boron vertices (B(2), B(4), B(5), and B(9)) of meta-carborane. Experimental and theoretical studies suggest this isomerization mechanism is strongly influenced by the steric crowding at the Pd catalyst by either a biaryl phosphine ligand and/or substrate. Ultimately, this "cage-walking" process provides a unique pathway to preferentially introduce functional groups at the B(2) vertex using B(9)-bromo-meta-carborane as the sole starting material through substrate control.

16.
J Am Chem Soc ; 138(22): 6952-5, 2016 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-27186856

RESUMEN

We report a discovery that perfunctionalized icosahedral dodecaborate clusters of the type B12(OCH2Ar)12 (Ar = Ph or C6F5) can undergo photo-excitation with visible light, leading to a new class of metal-free photooxidants. Excitation in these species occurs as a result of the charge transfer between low-lying orbitals located on the benzyl substituents and an unoccupied orbital delocalized throughout the boron cluster core. Here we show how these species, photo-excited with a benchtop blue LED source, can exhibit excited-state reduction potentials as high as 3 V and can participate in electron-transfer processes with a broad range of styrene monomers, initiating their polymerization. Initiation is observed in cases of both electron-rich and electron-deficient styrene monomers at cluster loadings as low as 0.005 mol%. Furthermore, photo-excitation of B12(OCH2C6F5)12 in the presence of a less activated olefin such as isobutylene results in the production of highly branched poly(isobutylene). This work introduces a new class of air-stable, metal-free photo-redox reagents capable of mediating chemical transformations.


Asunto(s)
Compuestos de Boro/química , Luz , Oxidantes/química , Polienos/química , Polímeros/química , Compuestos de Boro/efectos de la radiación , Transporte de Electrón , Modelos Moleculares , Estructura Molecular , Oxidación-Reducción , Procesos Fotoquímicos , Polimerizacion
18.
Int Ophthalmol ; 36(6): 901-905, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26909500

RESUMEN

The purpose of this study was to report on the occurrence and management of posterior synechiae (PS) in three hyperopic eyes after iris-fixated anterior chamber phakic IOL implantation. This is a case report of a 55-year-old man and a 55-year-old lady who had undergone iris-fixated anterior chamber phakic IOL implantation to correct hyperopic astigmatism (one eye) and hyperopia (both eyes), respectively. The three eyes developed creeping PS and pigment dispersion within 4-6 weeks of surgery. Synechiolysis and pupil stretching in one eye did not work as the synechiae promptly recurred. Definitive management in the form of removal of the phakic implant and phacoemulsification with lens implant was successful in restoring normal vision in all three eyes. Although implantation of phakic intraocular lenses has been reported to be very effective for the correction of moderate to high degrees of ametropia, this complication can occur in hyperopic eyes. Pigment dispersion has been reported in myopic eyes also, but PS seem to be more an issue with hyperopic eyes. Age of the patient may also be a factor. This information is important in the selection and counselling of patients.


Asunto(s)
Hiperopía/cirugía , Enfermedades del Iris/etiología , Iris/cirugía , Implantación de Lentes Intraoculares/efectos adversos , Lentes Intraoculares Fáquicas/efectos adversos , Complicaciones Posoperatorias/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad
19.
Eur J Ophthalmol ; : 11206721241251890, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38676318

RESUMEN

PURPOSE: To describe the outcomes of five Salzmann's Nodular Degeneration (SND) cases treated with a combination of alcohol delamination, superficial keratectomy and amniotic membrane patch with fibrin glue. METHODS: Five patients affected by SND with significant discomfort and decreased visual acuity were evaluated with refraction, best corrected visual acuity, Break-up time test, corneal topography, Anterior Segment of Optical Coherence Tomography and images of anterior segment with a full slit lamp examination. All the patients underwent alcohol delamination of the corneal epithelium followed by superficial keratectomy to remove the subepithelial nodules. A patch of amniotic membrane was applied to all of them with a ring shape and a banana shape in two patients due to the location of the disease. A bandage contact lens was inserted. The patch was kept in place for 14 days. Another bandage contact lens was inserted for 21 days until the corneal epithelium had completely healed. RESULTS: The surgical procedure was successful in removing the nodules in all patients. Vision was restored in all cases with a significant regularization of the corneal surface and reduction of ocular discomfort. After a 12-month follow-up, none of the patients showed recurrence of the disease. CONCLUSIONS: Combining alcohol delamination with superficial keratectomy and amniotic membrane patch with fibrin glue is an effective procedure for the management of SND to regularize the corneal surface and avoid the recurrence of subsequent nodules. This report is the first description of the outcomes of SND cases treated with a combination of the aforementioned techniques.

20.
Eur J Ophthalmol ; : 11206721241242165, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509758

RESUMEN

PURPOSE: The purpose of this paper is to report the increasing incidence of contact-lens related Acanthamoeba keratitis (AK) in a tertiary ophthalmology department in Umbria, central Italy. METHODS: Observational and retrospective case series were carried out. A total of nine eyes with a diagnosis of AK were examined. All patients underwent a full slit lamp examination, in vivo confocal microscopy (IVCM) and corneal scraping. The IVCM was repeated at one and two-week and at one, three and six-month intervals. Samples of domestic tap water were also examined for PCR analysis. Patients were treated with levofloxacin0,5%, Polyhexamethylene biguanide 0.02%, and Propamidine Isetionate0,1%. RESULTS: All patients were contact lens wearers. The average patient age was 27.75 (range 18-45), with three men and five women. The main clinical features were ciliary congestion, diffuse epitheliopathy with punctuated keratitis, multiple, small sub-epithelial, greyish, corneal infiltrates with epithelial defect, pseudodendritic corneal lesions, perineural infiltrates, corneal stromal cellularity, and stromal infiltrates. IVCM was indicative of Acanthamoeba in seven out of the nine eyes. All the positive IVCM images were section images showing double walled, bright-spot cysts with a clear chain-like arrangement of five or more cysts identified in three of the patients. PCR analysis of the water was negative in all cases. CONCLUSION: Although PCR is the most common method used, the increased incidence of AK could mainly be related to a proper IVCM interpretation. A broad-spectrum antibiotic, such as levofloxacin might play a role in the early treatment of AK reducing the virulence of the amoeba.

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