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1.
Lab Chip ; 23(13): 3016-3033, 2023 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-37294576

RESUMEN

Droplet injection strategies are a promising tool to reduce the large amount of sample consumed in serial femtosecond crystallography (SFX) measurements at X-ray free electron lasers (XFELs) with continuous injection approaches. Here, we demonstrate a new modular microfluidic droplet injector (MDI) design that was successfully applied to deliver microcrystals of the human NAD(P)H:quinone oxidoreductase 1 (NQO1) and phycocyanin. We investigated droplet generation conditions through electrical stimulation for both protein samples and implemented hardware and software components for optimized crystal injection at the Macromolecular Femtosecond Crystallography (MFX) instrument at the Stanford Linac Coherent Light Source (LCLS). Under optimized droplet injection conditions, we demonstrate that up to 4-fold sample consumption savings can be achieved with the droplet injector. In addition, we collected a full data set with droplet injection for NQO1 protein crystals with a resolution up to 2.7 Å, leading to the first room-temperature structure of NQO1 at an XFEL. NQO1 is a flavoenzyme associated with cancer, Alzheimer's and Parkinson's disease, making it an attractive target for drug discovery. Our results reveal for the first time that residues Tyr128 and Phe232, which play key roles in the function of the protein, show an unexpected conformational heterogeneity at room temperature within the crystals. These results suggest that different substates exist in the conformational ensemble of NQO1 with functional and mechanistic implications for the enzyme's negative cooperativity through a conformational selection mechanism. Our study thus demonstrates that microfluidic droplet injection constitutes a robust sample-conserving injection method for SFX studies on protein crystals that are difficult to obtain in amounts necessary for continuous injection, including the large sample quantities required for time-resolved mix-and-inject studies.


Asunto(s)
Rayos Láser , Proteínas , Humanos , Cristalografía por Rayos X , Proteínas/química , Inyecciones , NAD(P)H Deshidrogenasa (Quinona)
2.
Biophys Rep (N Y) ; 2(4): 100081, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36425668

RESUMEN

With advances in X-ray free-electron lasers (XFELs), serial femtosecond crystallography (SFX) has enabled the static and dynamic structure determination for challenging proteins such as membrane protein complexes. In SFX with XFELs, the crystals are typically destroyed after interacting with a single XFEL pulse. Therefore, thousands of new crystals must be sequentially introduced into the X-ray beam to collect full data sets. Because of the serial nature of any SFX experiment, up to 99% of the sample delivered to the X-ray beam during its "off-time" between X-ray pulses is wasted due to the intrinsic pulsed nature of all current XFELs. To solve this major problem of large and often limiting sample consumption, we report on improvements of a revolutionary sample-saving method that is compatible with all current XFELs. We previously reported 3D-printed injection devices coupled with gas dynamic virtual nozzles (GDVNs) capable of generating samples containing droplets segmented by an immiscible oil phase for jetting crystal-laden droplets into the path of an XFEL. Here, we have further improved the device design by including metal electrodes inducing electrowetting effects for improved control over droplet generation frequency to stimulate the droplet release to matching the XFEL repetition rate by employing an electrical feedback mechanism. We report the improvements in this electrically triggered segmented flow approach for sample conservation in comparison with a continuous GDVN injection using the microcrystals of lysozyme and 3-deoxy-D-manno-octulosonate 8-phosphate synthase and report the segmented flow approach for sample injection applied at the Macromolecular Femtosecond Crystallography instrument at the Linear Coherent Light Source for the first time.

3.
J Appl Crystallogr ; 55(Pt 1): 1-13, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35153640

RESUMEN

Serial femtosecond crystallography (SFX) is a powerful technique that exploits X-ray free-electron lasers to determine the structure of macro-molecules at room temperature. Despite the impressive exposition of structural details with this novel crystallographic approach, the methods currently available to introduce crystals into the path of the X-ray beam sometimes exhibit serious drawbacks. Samples requiring liquid injection of crystal slurries consume large quantities of crystals (at times up to a gram of protein per data set), may not be compatible with vacuum configurations on beamlines or provide a high background due to additional sheathing liquids present during the injection. Proposed and characterized here is the use of an immiscible inert oil phase to supplement the flow of sample in a hybrid microfluidic 3D-printed co-flow device. Co-flow generation is reported with sample and oil phases flowing in parallel, resulting in stable injection conditions for two different resin materials experimentally. A numerical model is presented that adequately predicts these flow-rate conditions. The co-flow generating devices reduce crystal clogging effects, have the potential to conserve protein crystal samples up to 95% and will allow degradation-free light-induced time-resolved SFX.

4.
Opt Express ; 28(15): 21749-21765, 2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-32752448

RESUMEN

Gas dynamic virtual nozzles (GDVNs) produce microscopic flow-focused liquid jets and droplets and play an important role at X-ray free-electron laser (XFEL) facilities where they are used to steer a stream of hydrated biomolecules into an X-ray focus during diffraction measurements. Highly stable and reproducible microjet and microdroplets are desired, as are flexible fabrication methods that enable integrated mixing microfluidics, droplet triggering mechanisms, laser illumination, and other customized features. In this study, we develop the use of high-resolution 3D nano-printing for the production of monolithic, asymmetric GDVN designs that are difficult to fabricate by other means. We also develop a dual-pulsed nanosecond image acquisition and analysis platform for the characterization of GDVN performance, including jet speed, length, diameter, and directionality, among others. We show that printed GDVNs can form microjets with very high degree of reproducibility, down to sub-micron diameters, and with water jet speeds beyond 170 m/s.

7.
Arch. esp. urol. (Ed. impr.) ; 60(10): 1197-1199, dic. 2007. ilus
Artículo en Español | IBECS | ID: ibc-135621

RESUMEN

OBJETIVO: Presentar un nuevo caso de metástasis renal de un carcinoma epidermoide de pulmón. MÉTODOS: Varón de 60 años remitido a consultas externas de urología por hallazgo ecográfico de una masa renal en estudio por microhematuria. RESULTADOS: Los estudios de imagen evidenciaron la presencia de una tumoración sólida en polo superior que se introducía hacia el seno renal, originando un atrapamiento de la arteria renal. El TC planteó el diagnóstico diferencial entre un carcinoma de células renales, un urotelioma o un proceso metastático. CONCLUSIONES: El cáncer de pulmón puede producir metástasis en cualquier órgano, pero el riñón no es uno de los órganos de asentamiento más frecuentes, sin embargo, la existencia de dos o más metástasis extratorácicas confieren un pobre pronóstico a esta patología (AU)


OBJECTIVE: To report a new case of renal metastasis from an squamous cell carcinoma of the lung. METHODS: A 60 year old male presented to the outpatient office with an ultrasound finding of renal mass. RESULTS: Imaging test studies showed a heterogeneous mass in the upper pole of the left kidney, involving the pelvis and trapping the renal artery. CONCLUSIONS: Clinically recognised or symptomatic metastases to the kidney from pulmonary cancer have been a rare occurrence. Nevertheless, prognosis associated with lung carcinoma metastatic to the kidney is very poor, since the likelihood of a truly solitary metastasis is remote (AU)


Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Carcinoma de Células Escamosas/secundario , Neoplasias Renales/secundario , Neoplasias Pulmonares/patología
10.
Arch Esp Urol ; 60(3): 237-44, 2007 Apr.
Artículo en Español | MEDLINE | ID: mdl-17601298

RESUMEN

OBJECTIVES: The objective of our study was to evaluate patient tolerance to transrectal ultrasound guided prostate biopsy using anesthesia with 2 grams of intrarectal lidocaine gel, and to evaluate the complications of the test. METHODS: 148 prostate biopsies with intrarectal lidocaine were performed over a four month period. The same intrarectal ultrasound transducer and needle mechanism were employed for all patients. Biopsies were performed by 7 different urologists with 6 to 12 cores per biopsy. All patients received after the biopsy a questionnaire to evaluate their tolerance to the intervention. In the same way, the urologist performing the biopsy filled a questionnaire about patient tolerance and complications of the test. RESULTS: Patient tolerance data were recorded in 147 biopsies. Twenty-five cases (16.9%) referred severe or unbearable pain, 45 patients (13.4%) referred no pain at all. A significant association between patients' and doctors' results was obtained. Digital rectal examination was painful in 10 cases only; transducer insertion was painful in 13, and 15 referred pain with the transducer movements inside the rectum. Almost all painful or unbearable core biopsies were taken in the apex. There was a significant association (p = 0.005) between the number of cores per biopsy and pain, being the pain more than expected when the number of cores was greater than six. Only 14 patients would not ever repeat the same biopsy or would request a different type of anesthesia and 133 (59.9%) of them would repeat it in the same way. CONCLUSIONS: In our experience, transrectal ultrasound guided prostatic biopsy is generally well tolerated with intrarectal gel as the only anesthesia. Nevertheless, the number of cores taken per biopsy has been the factor associated with pain, and if the number of biopsy cores increases additional anesthesia should be considered.


Asunto(s)
Anestésicos Locales/administración & dosificación , Biopsia con Aguja/efectos adversos , Lidocaína/administración & dosificación , Dolor/etiología , Dolor/prevención & control , Administración Rectal , Anciano , Anciano de 80 o más Años , Geles , Humanos , Persona de Mediana Edad , Dimensión del Dolor , Satisfacción del Paciente , Encuestas y Cuestionarios
12.
Arch Esp Urol ; 60(1): 99-102, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17408185

RESUMEN

OBJECTIVE: [corrected] To report a rare case of secondary testicular plasmocytoma in the context of a testicular mass. METHOD: We introduced a patient with plasmocytoma and a testicular infiltration of his systemic affection. RESULT: An inguinal orquiectomy was performed to treat the testicular infiltration and no recurrence of the process was seen after 6 months of follow up. CONCLUSIONS: Plasmacytoma is a plasma cell tumor that involves bone marrow or extramedullary sites. Testicular infiltration by plasma cells such as plasmacytoma happens in only 2% of cases of all plasma cell neoplasm


Asunto(s)
Vértebras Cervicales , Plasmacitoma/secundario , Neoplasias de la Columna Vertebral/patología , Neoplasias Testiculares/secundario , Humanos , Masculino , Persona de Mediana Edad
14.
Arch. esp. urol. (Ed. impr.) ; 60(3): 237-244, abr. 2007. ilus, tab
Artículo en Es | IBECS | ID: ibc-055380

RESUMEN

Objetivo: El objetivo de nuestro estudio, fue valorar la tolerancia por parte del paciente a una biopsia de próstata transrectal ecodirigida usando como método anestésico un gel con 2 gramos de lidocaina intrarectal, así como valorar las complicaciones de esta prueba. Método: Durante 4 meses consecutivos se realizaron 148 biopsias de próstata ecodirigidas usando 2 gramos de lidocaina intrarectal. Se usó el mismo transductor ecográfico transrectal en todos los pacientes, usándose también el mismo mecanismo de aguja para la obtención de los cilindros. Las biopsias fueron realizadas por 7 urólogos diferentes obteniéndose en cada biopsia entre 6 y 12 cilindros. A todos los pacientes se les entregó tras la prueba un cuestionario para valorar la tolerancia a este método. Así mismo, el médico que realizó las biopsias rellenaba un cuestionario a cerca del paciente en el que valoraba la tolerancia del paciente y las complicaciones tras la prueba. Resultados: Se recogieron los datos de tolerancia en 147 casos, existiendo dolor intenso o insoportable globalmente en 25 casos (16,9 %) y nada molesto en 45 pacientes (30,4 %). Se evidenció una asociación significativa entre el resultado del cuestionario del paciente y la percepción del médico que realizó la prueba. Sólo en 10 casos el tacto rectal fue doloroso, en 13 el paso del transductor y en 15 los movimientos del mismo en el recto. Prácticamente todos los cilindros que resultaron dolorosos o insoportables en la toma de muestras fueron los recogidos de la zona del ápex. Se encontró una asociación significativa (p=0,005) entre el número de cilindros y el dolor durante la obtención de los mismos, siendo mayor de lo esperado el dolor cuando se realizaron biopsias por encima de las sextantes. Sólo 14 pacientes no realizarían nuevamente la misma prueba o requerirían otro tipo de anestesia y el 89,9 % (133), volverían a realizarla en las mismas condiciones. Conclusiones: En nuestra experiencia la biopsia prostática ecodirigida es generalmente bien tolerada empleando únicamente un gel anestésico intrarectal. No obstante, el número de punciones durante la biopsia ha sido el factor asociado al dolor de la prueba y al incrementarse aquel debería plantearse el empleo de algún tipo adicional de anestesia (AU)


Objectives: The objective of our study was to evaluate patient tolerance to transrectal ultrasound guided prostate biopsy using anesthesia with 2 grams of intrarectal lidocaine gel, and to evaluate the complications of the test. Methods: 148 prostate biopsies with intrarectal lidocaine were performed over a four month period. The same intrarectal ultrasound transducer and needle mechanism were employed for all patients. Biopsies were performed by 7 different urologists with 6 to 12 cores per biopsy. All patients received after the biopsy a questionnaire to evaluate their tolerance to the intervention. In the same way, the urologist performing the biopsy filled a questionnaire about patient tolerance and complications of the test. Results: Patient tolerance data were recorded in 147 biopsies. Twenty-five cases (16.9%) referred severe or unbearable pain, 45 patients (13.4%) referred no pain at all. A significant association between patients' and doctors' results was obtained. Digital rectal examination was painful in 10 cases only; transducer insertion was painful in 13, and 15 referred pain with the transducer movements inside the rectum. Almost all painful or unbearable core biopsies were taken in the apex. There was a significant association (p = 0.005) between the number of cores per biopsy and pain, being the pain more than expected when the number of cores was greater than six. Only 14 patients would not ever repeat the same biopsy or would request a different type of anesthesia and 133 (59.9%) of them would repeat it in the same way. Conclusions: In our experience, transrectal ultrasound guided prostatic biopsy is generally well tolerated with intrarectal gel as the only anesthesia. Nevertheless, the number of cores taken per biopsy has been the factor associated with pain, and if the number of biopsy cores increases additional anesthesia should be considered (AU)


Asunto(s)
Masculino , Persona de Mediana Edad , Anciano , Humanos , Enfermedades de la Próstata/complicaciones , Enfermedades de la Próstata/diagnóstico , Enfermedades de la Próstata , Biopsia/métodos , Lidocaína , Encuestas y Cuestionarios , Anestesia Rectal/métodos , Adenocarcinoma/complicaciones , Adenocarcinoma/diagnóstico , Próstata/patología , Próstata/cirugía , Próstata , Dimensión del Dolor/métodos , Dimensión del Dolor/estadística & datos numéricos , Neoplasias de la Próstata/diagnóstico
15.
Arch. esp. urol. (Ed. impr.) ; 60(1): 99-102, ene.-feb. 2007. ilus
Artículo en En | IBECS | ID: ibc-054464

RESUMEN

OBJETIVOS: To report a rare case of secondary testicular plasmocytoma in the context of a testicular mass. METODOS: We introduced a patient with plasmocytoma and a testicular infiltration of his systemic affection. RESULTADOS: An inguinal orquiectomy was performed to treat the testicular infiltration and no recurrence of the process was seen after 6 months of follow up. CONCLUSIONES: Plasmacytoma is a plasma cell tumor that involves bone marrow or extramedullary sites. Testicular infiltration by plasma cells such as plasmacytoma happens in only 2 % of cases of all plasma cell neoplasm (AU)


Objetivo: Presentar un caso raro de plasmocitoma testicular secundario en el contexto de una masa testicular. Métodos: Se trata de un paciente con un plasmocitoma y con infiltración testicular de su proceso sistémico. Resultado: Para tratarlo se realizó una orquiectomía por vía inguinal, sin presentar recidiva de su proceso sistémico tras 6 meses de seguimiento. Conclusiones: El plasmocytoma es una tumoración de células plasmáticas que puede asentar sobre la médula ósea o sobre zonas extramedulares. La infiltración testicular por células plasmáticas ocurre sólo en el 2 % de los caso de tumores de células plasmáticas (AU)


Asunto(s)
Masculino , Persona de Mediana Edad , Humanos , Vértebras Cervicales , Plasmacitoma/secundario , Neoplasias de la Columna Vertebral/patología , Neoplasias Testiculares/secundario
17.
Arch Esp Urol ; 60(10): 1.197-1.199, 2007 Dec.
Artículo en Español | MEDLINE | ID: mdl-18273977

RESUMEN

OBJECTIVE: To report a new case of renal metastasis from an squamous cell carcinoma of the lung. METHODS: A 60 year old male presented to the outpatient office with an ultrasound finding of renal mass. RESULTS: Imaging test studies showed a heterogeneous mass in the upper pole of the left kidney, involving the pelvis and trapping the renal artery. CONCLUSIONS: Clinically recognised or symptomatic metastases to the kidney from pulmonary cancer have been a rare occurrence. Nevertheless, prognosis associated with lung carcinoma metastatic to the kidney is very poor, since the likelihood of a truly solitary metastasis is remote.


Asunto(s)
Carcinoma de Células Escamosas/secundario , Neoplasias Renales/secundario , Neoplasias Pulmonares/patología , Humanos , Masculino , Persona de Mediana Edad
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