Síntesis y radiomarcado de un conjugado heterobivalente de bombesina y ácido fólico para la evaluación de la actividad metabólica de células de cáncer de mama

Las moléculas heterobivalentes radiomarcadas han mostrado ser una estrategia adecuada para obtener imágenes del tumor de manera sensible, específica y no invasiva debido a que interactúan concomitantemente con diferentes blancos moleculares sobre la célula tumoral. Una de las características fenotípicas de las células de cáncer de mama es la sobre-expresión de receptores de membrana que regulan el comportamiento celular. Entre estos receptores se encuentran el receptor del péptido liberador de gastrina (GRPR) y el receptor de folatos (FR), los cuales al unirse con alta afinidad a la Bombesina y ácido fólico/folato respectivamente, producen respuestas celulares que favorecen el crecimiento y proliferación celular. El objetivo del presente trabajo fue sintetizar y caracterizar químicamente los conjugados heterobivalentes Lys1(α,γ-folato)Lys3(99mTc-HYNIC)-Bombesina (1-14) y Lys1(α,γ-folato)Lys3(177Lu-DOTA)-Bombesina (1-14), con la finalidad de evaluar tanto in vitro como in vivo su potencial como radiofármacos heterobivalentes para diagnóstico y/o tratamiento de células de cáncer de mama +GRPR y +FR. Adicionalmente, se evaluó el potencial de Lys1(α,γ-folato)Lys3(99mTc-HYNIC)-Bombesina (1-14) para medir la actividad metabólica de dichas células a través de imágenes SPECT. Para obtener a los conjugados Lys1(α,γ-folato)Lys3(HYNIC)-Bombesina (1-14) y Lys1(α,γ-folato)Lys3(DOTA)-Bombesina (1-14), los péptidos Lys1Lys3(HYNIC)-Bombesina (1-14) y Lys1Lys3(DOTA)-Bombesina (1-14) se conjugaron a ácido fólico mediante un enlace amida. Los productos se purificaron por HPLC de exclusión molecular y se caracterizaron por espectroscopia UV-Vis, IR-FT y espectrometría de masas MALDI-TOF. El radiomarcado de Lys1(α,γ-folato)Lys3(HYNIC)-Bombesina (1-14) con 99mTc se realizó con EDDA/tricina como coligantes y SnCl2 como agente reductor. Para el radiomarcado de Lys1(α,γ-folato)Lys3(DOTA)-Bombesina (1-14) con 177Lu, se utilizó 177LuCl3 diluido con buffer de acetato 1 M a pH=5. La pureza radioquímica se evaluó en un HPLC en fase reversa. Se evaluó la estabilidad de los conjugados heterobivalentes Lys1(α,γ-folato)Lys3(99mTc-HYNIC)-Bombesina (1-14) y Lys1(α,γ-folato)Lys3(177Lu-DOTA)-Bombesina (1-14) en suero humano. Se determinó la afinidad de los conjugados heterobivalentes a la proteína recombinante GRPR y a la proteína humana FR. La captación in vitro se evaluó en células de cáncer de mama T47D (+GRPR y +FR). La biodistribución y captación en el tumor se determinaron en ratones atímicos con tumores inducidos T47D. Para evaluar la especificidad de los conjugados heterobivalentes, tanto en los estudios in vitro como in vivo se bloquearon los receptores GRPR y FR. Los estudios de imagen en ratones atímicos con tumores T47D se obtuvieron con un micro-SPECT/CT. La actividad metabólica del tumor se determinó a partir de imágenes SPECT/CT utilizando Lys1(α,γ-folato)Lys3(99mTc-HYNIC)-Bombesina (1-14) y se comparó con 18F-FDG y 99mTc-Folato. Se estimó la dosis absorbida en el tumor, riñón, hígado y páncreas a partir de la actividad acumulada en la región de interés. Los resultados obtenidos en los estudios in vitro e in vivo se compararon con sus respectivos monómeros Lys1Lys3(99mTc-HYNIC)-Bombesina (1-14) y Lys1Lys3(177Lu-DOTA)-Bombesina (1-14). Los estudios espectroscópicos y el análisis por HPLC indicaron que los conjugados heterobivalentes se obtuvieron con alta pureza química y alta pureza radioquímica (>95%). Los conjugados heterobivalentes Lys1(α,γ-folato)Lys3(99mTc-HYNIC)-Bombesina (1-14) y Lys1(α,γ-folato)Lys3(177Lu-DOTA)-Bombesina (1-14) mostraron alta estabilidad en suero humano con 2% de unión a proteínas a las 2 h de incubación. Ambos conjugados mostraron alta afinidad a la proteína recombinante del GRPR y a la proteína humana del RF. Los estudios in vitro mostraron que los conjugados heterobivalentes tienen reconocimiento específico a las células de cáncer de mama T47D +GRPR y +FR, y mostraron un incremento en la captación debido al efecto concomitante entre la unión Bombesina-GRPR- y Folato-FR. Los estudios de biodistribución de los conjugados heterobivalentes en ratones atímicos con tumores inducidos T47D, mostraron alta captación en el tumor con alto contraste en las imágenes SPECT/CT. Lys1(α,γ-folato)Lys3(99mTc-HYNIC)-Bombesina (1-14) permitió evaluar a través de imagen la actividad metabólica del tumor. El compuesto Lys1(α,γ-folato)Lys3(177Lu-DOTA)-Bombesina (1-14) mejoró la dosis absorbida al tumor debido a la unión concomitante de Bombesina-GRPR y Folato-FR. Este estudio demostró que los conjugados heterobivalentes Lys1(α,γ-folato)Lys3(99mTc-HYNIC)-Bombesina (1-14) y Lys1(α,γ-folato)Lys3(177Lu-DOTA)-Bombesina (1-14) mejoran la detección de células de cáncer de mama +GRPR y +FR, por lo que, pueden ser utilizados para el diagnóstico y/o tratamiento de tumores de mama que sobre-expresan GRPR y FR.Financiamiento CONACYT (CONACYT-SEP-CB-2014-01-242443

Differences in the S value between male and female murine model for diagnostic, therapeutic and theragnostic radionuclides

The aim of this work was to calculate S values for 99mTc, 67Ga, 68Ga, 18F, 223Ra, 166Ho, 90Y, 161Tb 131I and 177Lu, using a mouse phantom (MOBY) standard and considering the anatomic sizes from males and females, the simulation of radiation transport was performed with GATE/Geant4 platform. This indicates that in the internal dosimetry the use of a customized geometry is relevant for each gender and a standard model is not a good choice

Engineered rHDL Nanoparticles as a Suitable Platform for Theranostic Applications

Reconstituted high-density lipoproteins (rHDLs) can transport and specifically release drugs and imaging agents, mediated by the Scavenger Receptor Type B1 (SR-B1) present in a wide variety of tumor cells, providing convenient platforms for developing theranostic systems. Usually, phospholipids or Apo-A1 lipoproteins on the particle surfaces are the motifs used to conjugate molecules for the multifunctional purposes of the rHDL nanoparticles. Cholesterol has been less addressed as a region to bind molecules or functional groups to the rHDL surface. To maximize the efficacy and improve the radiolabeling of rHDL theranostic systems, we synthesized compounds with bifunctional agents covalently linked to cholesterol. This strategy means that the radionuclide was bound to the surface, while the therapeutic agent was encapsulated in the lipophilic core. In this research, HYNIC-S-(CH2)3-S-Cholesterol and DOTA-benzene-p-SC-NH-(CH2)2-NH-Cholesterol derivatives were synthesized to prepare nanoparticles (NPs) of HYNIC-rHDL and DOTA-rHDL, which can subsequently be linked to radionuclides for SPECT/PET imaging or targeted radiotherapy. HYNIC is used to complexing 99mTc and DOTA for labeling molecules with 111, 113mIn, 67, 68Ga, 177Lu, 161Tb, 225Ac, and 64Cu, among others. In vitro studies showed that the NPs of HYNIC-rHDL and DOTA-rHDL maintain specific recognition by SR-B1 and the ability to internalize and release, in the cytosol of cancer cells, the molecules carried in their core. The biodistribution in mice showed a similar behavior between rHDL (without surface modification) and HYNIC-rHDL, while DOTArHDL exhibited a different biodistribution pattern due to the significant reduction in the lipophilicity of the modified cholesterol molecule. Both systems demonstrated characteristics for the development of suitable theranostic platforms for personalized cancer treatment.Consejo Nacional de Ciencia y Tecnología (CONACyT, Mexico), through Grant SEP-CONACyT-CB-2016-01-287217. the financing program for female scientists EDOMEX, Grant Number FICDTEM-2021-015

177Lu-Dendrimer conjugated to folate and bombesin with gold nanoparticles in the dendritic cavity: A potential theranostic radiopharmaceutical

177Lu-labeled nanoparticles conjugated to biomolecules have been proposed as a new class of theranostic radiopharmaceuticals. The aim of this research was to synthesize 177Lu-dendrimer(PAMAM-G4)-folate-bombesin with gold nanoparticles (AuNPs) in the dendritic cavity and to evaluate the radiopharmaceutical potential for targeted radiotherapy and the simultaneous detection of folate receptors (FRs) and gastrin-releasing peptide receptors (GRPRs) overexpressed in breast cancer cells. p-SCN-Benzyl-DOTA was conjugated in aqueous-basic medium to the dendrimer.The carboxylate groups of Lys1Lys3(DOTA)-bombesin and folic acid were activatedwithHATUand also conjugated to the dendrimer.The conjugate was mixed with 1%HAuCl4 followed by the addition of NaBH4 and purified by ultrafiltration. Elemental analysis (EDS), particle size distribution (DLS), TEM analysis, UV-Vis, and infrared and fluorescence spectroscopies were performed. The conjugate was radiolabeled using 177LuCl3 or 68GaCl3 and analyzed by radio-HPLC. Studies confirmed the dendrimer functionalization with high radiochemical purity (>95%). Fluorescence results demonstrated that the presence ofAuNPs in the dendritic cavity confers useful photophysical properties to the radiopharmaceutical for optical imaging. Preliminary binding studies in T47D breast cancer cells showed a specific cell uptake (41.15 ± 2.72%). 177Ludendrimer( AuNP)-folate-bombesin may be useful as an optical and nuclear imaging agent for breast tumors overexpressing GRPR and FRs, as well as for targeted radiotherapy.CONACYT-SEP-CB-2014-01-242443 International Atomic Energy Agency (Grant 18358) LaboratorioNacional de Investigaci´on yDesarrollo de Radiof´armacos, CONACy

Soy Niña

Este libro pretende contribuir al reencuentro de la educación con esas finalidades que verdaderamente importan a una niña o un niño: ser feliz, jugar, vivir juntos y (no) aprender. Para ello hemos puesto el arte, nuestras experiencias y el saber acumulado al servicio del disfrute, el cuestionamiento, el análisis crítico y la construcción común de un presente deseable. Un texto colaborativo coordinado por Ignacio Calderón Almendros y realizado por alumnado de Educación y Cambio Social en el Grado en Educación Infantil de la Universidad de Málaga

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Síntesis y evaluación del radiofármaco 99mTc-EDDA/HYNIC-Gly-Gly-Cys-(a,y)-Folato

El ácido fólico reconoce específicamente al receptor folato (RF) sobreexpresado en carcinomas. Los radiofármacos de folato tienen afinidad por RF pero alta captación renal. La secuencia Gly-Gly-Cys mejora la eliminación renal. El objetivo fue sintetizar el 99mTc-EDDA/HYNIC-Gly-Gly-Cys(α,γ)-Folato y evaluar su potencial in vitro e in vivo para reconocer RF. El conjugado se caracterizó químicamente (UV-Vis, FT- IR , MALDI-TOF) y se radiomarcó con 99mTc . La afinidad in vitro y la biodistribución se evaluaron en células T47D (FR+) y en ratones atímicos con tumores inducidos. 99mTc-EDDA/HYNICGly-Gly-Cys(α,γ)-Folato mostró alta pureza radioquímica (> 94 %) , afinidad por los RF (IC50=0.3nM), rápida eliminación sanguínea, captación tumoral adecuada (2.4 % ID/g a 2h) , y retención renal baja (1.6 % ID/g a 24 h). 99mTc-EDDA/HYNICGly-Gly-Cys(α,γ)-Folato es útil como un agente de imagen para reconocer RF

177Lu-Dendrimer Conjugated to Folate and Bombesin with Gold Nanoparticles in the Dendritic Cavity: A Potential Theranostic Radiopharmaceutical

177Lu-labeled nanoparticles conjugated to biomolecules have been proposed as a new class of theranostic radiopharmaceuticals. The aim of this research was to synthesize 177Lu-dendrimer(PAMAM-G4)-folate-bombesin with gold nanoparticles (AuNPs) in the dendritic cavity and to evaluate the radiopharmaceutical potential for targeted radiotherapy and the simultaneous detection of folate receptors (FRs) and gastrin-releasing peptide receptors (GRPRs) overexpressed in breast cancer cells. p-SCN-Benzyl-DOTA was conjugated in aqueous-basic medium to the dendrimer. The carboxylate groups of Lys1Lys3(DOTA)-bombesin and folic acid were activated with HATU and also conjugated to the dendrimer. The conjugate was mixed with 1% HAuCl4 followed by the addition of NaBH4 and purified by ultrafiltration. Elemental analysis (EDS), particle size distribution (DLS), TEM analysis, UV-Vis, and infrared and fluorescence spectroscopies were performed. The conjugate was radiolabeled using 177LuCl3 or 68GaCl3 and analyzed by radio-HPLC. Studies confirmed the dendrimer functionalization with high radiochemical purity (>95%). Fluorescence results demonstrated that the presence of AuNPs in the dendritic cavity confers useful photophysical properties to the radiopharmaceutical for optical imaging. Preliminary binding studies in T47D breast cancer cells showed a specific cell uptake (41.15±2.72%). 177Lu-dendrimer(AuNP)-folate-bombesin may be useful as an optical and nuclear imaging agent for breast tumors overexpressing GRPR and FRs, as well as for targeted radiotherapy