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1.
Mod Pathol ; 37(9): 100559, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38969271

RESUMEN

Fluorescence confocal microscopy (FCM) is an optical technique that uses laser light sources of different wavelengths to generate real-time images of fresh, unfixed tissue specimens. Unlike conventional histologic evaluation methods, FCM is able to assess fresh tissue samples without the associated cryo artifacts typically observed after frozen sectioning. The purpose of this study was to evaluate the utility of FCM imaging in the differential diagnosis of cervical lymphadenopathy. Twenty-two cervical lymph node specimens from patients with lymphadenopathy of unknown origin were imaged by FCM. Two pathologists independently evaluated the scans for suspicion of malignancy and preliminary diagnosis. Malignancy was reliably excluded or confirmed by both pathologists with a sensitivity of 90.9% for pathologist 1 and 100% for pathologist 2. The specificity was 100% for both pathologists. For the preliminary diagnosis, almost perfect agreement with the final diagnosis was observed for both pathologists (κ = 0.94 for pathologist 1 and κ = 1.00 for pathologist 2). This is the first study to investigate lymph node specimens with different diagnoses, including lymphoma, using FCM. Our results indicate that differential diagnosis of lymph node specimens is feasible in FCM images, thus encouraging further exploration of FCM imaging in lymph node specimens to accelerate diagnosis and open the possibility of digitizing diagnosis on fresh, unfixed tissue.

2.
Br J Cancer ; 129(10): 1667-1678, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37723317

RESUMEN

BACKGROUND: Neuroblastoma is a paediatric cancer that is characterised by poor prognosis for chemoresistant disease, highlighting the need for better treatment options. Here, we asked whether BH3-mimetics inhibiting BCL2 proteins may eliminate chemoresistant neuroblastoma cells. METHODS: We utilised cisplatin-adapted neuroblastoma cell lines as well as patient tissues before and after relapse to study alterations of BCL2 proteins upon chemoresistance. RESULTS: In a direct comparison of cisplatin-resistant cells we identified a prominent loss of sensitivity to BCL2/BCL-XL inhibitors that is associated with an increase in MCL1 dependency and high expression of MCL1 in patient tumour tissues. Screening of FDA-approved anti-cancer drugs in chemoresistant cells identified therapeutics that may be beneficial in combination with the clinically tested BH3-mimetic ABT263, but no synergistic drug interactions with the selective MCL1 inhibitor S63845. Further exploration of potential treatment options for chemoresistant neuroblastoma identified immunotherapy based on NK cells as highly promising, since NK cells are able to efficiently kill both parental and chemoresistant cells. CONCLUSIONS: These data highlight that the application of BH3-mimetics may differ between first line treatment and relapsed disease. Combination of NK cell-based immunotherapy with BH3-mimetics may further increase killing of chemoresistant neuroblastoma, outlining a new treatment strategy for relapsed neuroblastoma.


Asunto(s)
Antineoplásicos , Neuroblastoma , Niño , Humanos , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Cisplatino/farmacología , Línea Celular Tumoral , Recurrencia Local de Neoplasia/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Neuroblastoma/tratamiento farmacológico , Antineoplásicos/farmacología , Apoptosis
3.
J Pediatr Hematol Oncol ; 45(3): 105-110, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36251795

RESUMEN

Metachronous osteosarcomas (MOS) are currently defined as tumors that arise in a way and site unusual for typical metastasis. In this article, we reviewed the recent literature on the occurrence of metachronous osteosarcoma and presented a case from our center. Our patient, a 10-year-old girl, presented with metachronous osteoblastic osteosarcoma of the left distal femur ∼5 years after the successful treatment for osteosarcoma of the right distal femur. Even after several relapses, complete remission (CR) was achieved after the first osteosarcoma and after the metachronous osteosarcoma. The literature research revealed that metachronous osteosarcoma occurs in 3.4 to 5.4% of osteosarcoma patients. The time interval between the diagnosis of the initial osteosarcoma and the metachronous tumor ranged from 0.2 to 14.3 years (median 2.5 y). MOS appears to have differences in localization and metastatic spread, as well as a different survival pattern compared with primary osteosarcoma and osteosarcoma recurrence. Survival (median 4.3 y, range 0 to 24.6 y) appears to be associated with the time interval to diagnosis of MOS. In particular, early MOS (<24 mo after primary diagnosis) seem to have a poorer prognosis. Therefore, the occurrence of MOS at oncological unusual sites should be considered as a differential diagnosis in osteosarcoma survivors.


Asunto(s)
Neoplasias Óseas , Neoplasias Primarias Secundarias , Osteosarcoma , Femenino , Humanos , Niño , Neoplasias Primarias Secundarias/patología , Diagnóstico Diferencial , Neoplasias Óseas/patología , Recurrencia Local de Neoplasia/diagnóstico , Osteosarcoma/diagnóstico , Osteosarcoma/terapia , Osteosarcoma/patología
4.
Pediatr Dev Pathol ; 26(3): 287-291, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36994845

RESUMEN

BACKGROUND: Hirschsprung disease (HD) is an aganglionosis of variable length starting at the rectosigmoid colon with surgery as sole therapeutic option. The length of the resected bowel segment is a crucial information for the treating surgeons and influences the prognosis of the patient. It is often artificially altered due to post operative tissue shrinkage. The objective of this study is to quantify the extent tissue shrinkage of HD specimens. MATERIAL AND METHODS: Colorectal HD specimens were measured at the time of surgery and at the time of cut-up, either fresh or after formalin fixation and statistically analyzed. RESULTS: Sixteen colorectal specimens were included. Following formalin fixation the specimen length decreased by 22.7% (P < .001). Without formalin fixation the specimens shrank by an average of 24.9% (P = .05). There was no significant difference in the extent of tissue shrinkage with or without formalin fixation (P = .76). CONCLUSION: This study showed that there is significant tissue shrinkage in HD specimens. The 2 different cohorts revealed that tissue shrinkage is mostly caused by tissue retraction/alteration after organ removal but also to a lesser extent by fixation with formalin. Surgeons and (neuro-)pathologists should be aware of the sizeable shrinking artifact to avoid unnecessary confusion.


Asunto(s)
Neoplasias Colorrectales , Enfermedad de Hirschsprung , Cirujanos , Niño , Humanos , Enfermedad de Hirschsprung/diagnóstico , Enfermedad de Hirschsprung/cirugía , Enfermedad de Hirschsprung/patología , Recto/patología , Formaldehído , Neoplasias Colorrectales/patología
5.
Int J Legal Med ; 136(2): 475-482, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35091851

RESUMEN

Sudden cardiac death (SCD) in adolescents and young adults may be the first manifestation of an inherited arrhythmic syndrome. Thus identification of a genetic origin in sudden death cases deemed inconclusive after a comprehensive autopsy and may help to reduce the risk of lethal episodes in the remaining family. Using next-generation sequencing (NGS), a large number of variants of unknown significance (VUS) are detected. In the majority of cases, there is insufficient evidence of pathogenicity, representing a huge dilemma in current genetic investigations. Misinterpretation of such variants may lead to inaccurate genetic diagnoses and/or the adoption of unnecessary and/or inappropriate therapeutic approaches. In our study, we applied current (ACMG) recommendations for variant classification in post-mortem genetic screening of a cohort of 56 SCD victims. We identified a total 53 rare protein-altering variants (MAF < 0.2%) classified as VUS or worse. Twelve percent of the cases exhibited a clinically actionable variant (pathogenic, likely pathogenic or VUS - potentially pathogenic) that would warrant cascade genetic screening in relatives. Most of the variants detected by means of the post-mortem genetic investigations were VUS. Thus, genetic testing by itself might be fairly meaningless without supporting background data. This data reinforces the need for an experienced multidisciplinary team for obtaining reliable and accountable interpretations of variant significance for elucidating potential causes for SCDs in the young. This enables the early identification of relatives at risk or excludes family members as genetic carriers. Also, development of adequate forensic guidelines to enable appropriate interpretation of rare genetic variants is fundamental.


Asunto(s)
Muerte Súbita Cardíaca , Pruebas Genéticas , Adolescente , Autopsia , Estudios de Cohortes , Muerte Súbita Cardíaca/etiología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Adulto Joven
6.
Int J Colorectal Dis ; 37(9): 1963-1973, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35931782

RESUMEN

PURPOSE: The use of laparoscopic surgery for colorectal cancer in elderly patients with high comorbidity is a controversial subject. This retrospective analysis aims to compare two different age groups with respect to short and long term clinical and oncological outcomes. METHODS: All laparoscopic colorectal resections for cancer performed between February 2011 and October 2017 with curative or palliative intention were evaluated. RESULTS: Among 128 completed resections, the rate of major complications, length of hospital stays, 30-day mortality, 2-year recurrence rate, and the survival after palliative surgery were comparable between group A (< 75 years; n = 76) and B (≥ 75 years; n = 52). Patients in group B showed an extraordinarily high proportion of ASA III stage (73.1% vs. A: 35.5%; p < 0.01) and, in this context, an increased rate of minor postoperative complications (17.3% vs. A: 6.6%; p < 0.05) and lower overall 2 and 5-year survival rates. Within the first 2 years, they died sooner in the event of recurrence (57.1% vs. A: 18.2%; p < 0.05), and their survival after rectal resection, especially for low rectal carcinoma, was significantly reduced (58.8% vs. A: 96.7%; p < 0.001). CONCLUSION: Laparoscopic surgery for colorectal cancer can be strongly advocated for elderly patients even in the face of high comorbidity. Whether very old patients with low rectal carcinoma also benefit from minimally invasive surgery or should undergo alternative therapies would need to be clarified primarily by examining the quality of life.


Asunto(s)
Carcinoma , Neoplasias Colorrectales , Laparoscopía , Neoplasias del Recto , Anciano , Carcinoma/cirugía , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/cirugía , Comorbilidad , Humanos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Complicaciones Posoperatorias/epidemiología , Calidad de Vida , Neoplasias del Recto/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
7.
Int J Mol Sci ; 22(23)2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34884497

RESUMEN

Recently, we reported a case of an infant with neonatal severe under-mineralizing skeletal dysplasia caused by mutations within both alleles of the TRPV6 gene. One mutation results in an in frame stop codon (R510stop) that leads to a truncated, nonfunctional TRPV6 channel, and the second in a point mutation (G660R) that, surprisingly, does not affect the Ca2+ permeability of TRPV6. We mimicked the subunit composition of the unaffected heterozygous parent and child by coexpressing the TRPV6 G660R and R510stop mutants and combinations with wild type TRPV6. We show that both the G660R and R510stop mutant subunits are expressed and result in decreased calcium uptake, which is the result of the reduced abundancy of functional TRPV6 channels within the plasma membrane. We compared the proteomic profiles of a healthy placenta with that of the diseased infant and detected, exclusively in the latter two proteases, HTRA1 and cathepsin G. Our results implicate that the combination of the two mutant TRPV6 subunits, which are expressed in the placenta of the diseased child, is responsible for the decreased calcium uptake, which could explain the skeletal dysplasia. In addition, placental calcium deficiency also appears to be associated with an increase in the expression of proteases.


Asunto(s)
Canales de Calcio/genética , Catepsina G/metabolismo , Serina Peptidasa A1 que Requiere Temperaturas Altas/metabolismo , Mutación , Osteocondrodisplasias/patología , Placenta/patología , Proteoma/metabolismo , Canales Catiónicos TRPV/genética , Secuencia de Aminoácidos , Animales , Canales de Calcio/metabolismo , Canales de Calcio/fisiología , Estudios de Casos y Controles , Catepsina G/genética , Femenino , Regulación Enzimológica de la Expresión Génica , Serina Peptidasa A1 que Requiere Temperaturas Altas/genética , Humanos , Lactante , Ratones Noqueados , Osteocondrodisplasias/etiología , Osteocondrodisplasias/metabolismo , Placenta/metabolismo , Embarazo , Proteoma/análisis , Canales Catiónicos TRPV/metabolismo , Canales Catiónicos TRPV/fisiología
8.
BMC Med Genet ; 21(1): 64, 2020 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-32228492

RESUMEN

BACKGROUND: The calcium-selective channel TRPV6 (transient receptor potential cation channel subfamily V member 6) is crucial for maternal-fetal calcium transport across the placenta. TRPV6 mutations have recently been associated with an antenatally severe under-mineralising skeletal dysplasia accompanied by postnatal biochemical abnormalities. This is the first post-mortem report in a patient with TRPV6 skeletal dysplasia. CASE PRESENTATION: The female infant had severe antenatal and postnatal skeletal abnormalities by 20 weeks gestation and was ventilator-dependent from birth. These skeletal abnormalities were apparent at an earlier gestational age than in previous reported cases and a more severe clinical course ensued. Biochemical and skeletal abnormalities, including bone density, improved postnatally but cardiac arrest at 4 months of age led to withdrawal of intensive care. Compound heterozygous TRPV6 variants (c.1978G > C p.(Gly660Arg) and c.1528C > T p.(Arg510Ter)) were identified on exome sequencing. Post-mortem identified skeletal abnormalities but no specific abnormalities in other organ systems. No placental pathology was found, multi-organ histological features reflected prolonged intensive care only. Post-mortem macroscopic examination indicated reduced thoracic size and short, pale and pliable ribs. Histological examination identified reduced number of trabeculae in the diaphyses (away from the growth plates), whereas metaphyses showed adequate mineralisation and normal number of trabeculae, but with slightly enlarged reactive chondrocytes, indicating post-natal skeletal growth recovery. Post-mortem radiological findings demonstrated improved bone density, improved rib width, healed fractures, although ribs were still shorter than normal. Long bones (especially humerus and femur) had improved from initial poorly defined metaphyses and reduced bone density to sharply defined metaphyses, prominent growth restart lines in distal diaphyses and bone-in-bone appearance along diaphyses. CONCLUSIONS: This case provide bone histological confirmation that human skeletal development is compromised in the presence of TRPV6 pathogenic variants. Post-mortem findings were consistent with abnormal in utero skeletal mineralisation due to severe calcium deficit from compromised placental calcium transfer, followed by subsequent phenotypic improvement with adequate postnatal calcium availability. Significant skeletal recovery occurs in the early weeks of postnatal life in TRPV6 skeletal dysplasia.


Asunto(s)
Desarrollo Óseo , Huesos/patología , Canales de Calcio/genética , Desarrollo Infantil/fisiología , Osteocondrodisplasias/genética , Osteocondrodisplasias/patología , Canales Catiónicos TRPV/genética , Autopsia , Desarrollo Óseo/genética , Huesos/anomalías , Calcificación Fisiológica/genética , Calcio/metabolismo , Canales de Calcio/análisis , Análisis Mutacional de ADN , Femenino , Humanos , Lactante , Osteocondrodisplasias/rehabilitación , Parto/fisiología , Canales Catiónicos TRPV/análisis
9.
Int J Legal Med ; 134(5): 1753-1763, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32399898

RESUMEN

In murine models, the expression of inducible nitric oxide synthase (iNOS) in myocardial infarction (MI) has been reported to be the result of tissue injury and inflammation. In the present study, mRNA expression of iNOS, hypoxia-inducible factor-1α (HIF-1α), and vascular endothelial growth factor (VEGF) was investigated in postmortem human infarction hearts. Since HIF-1α is the inducible subunit of the transcription factor HIF-1, which regulates transcription of iNOS and VEGF, the interrelation between the three genes was observed, to examine the molecular processes during the emergence of MI. iNOS and VEGF mRNAs were found to be significantly upregulated in the affected regions of MI hearts in comparison to healthy controls. Upregulation of HIF-1α was also present but not significant. Correlation analysis of the three genes indicated a stronger and significant correlation between HIF-1α and iNOS mRNAs than between HIF-1α and VEGF. The results of the study revealed differences in the expression patterns of HIF-1 downstream targets. The stronger transcription of iNOS by HIF-1 in the affected regions of MI hearts may represent a pathological process, since no correlation of iNOS and HIF-1α mRNA was found in non-affected areas of MI hearts. Oxidative stress is considered to cause molecular changes in MI, leading to increased iNOS expression. Therefore, it may also represent a forensic marker for detection of early changes in heart tissue.


Asunto(s)
Expresión Génica , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Infarto del Miocardio/patología , Óxido Nítrico Sintasa de Tipo II/metabolismo , ARN Mensajero/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Femenino , Humanos , Masculino , Cambios Post Mortem , Regulación hacia Arriba/genética
10.
Int J Mol Sci ; 21(14)2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-32698485

RESUMEN

Depletion of yeast/fly Ataxin-2 rescues TDP-43 overexpression toxicity. In mouse models of Amyotrophic Lateral Sclerosis via TDP-43 overexpression, depletion of its ortholog ATXN2 mitigated motor neuron degeneration and extended lifespan from 25 days to >300 days. There is another ortholog in mammals, named ATXN2L (Ataxin-2-like), which is almost uncharacterized but also functions in RNA surveillance at stress granules. We generated mice with Crispr/Cas9-mediated deletion of Atxn2l exons 5-8, studying homozygotes prenatally and heterozygotes during aging. Our novel findings indicate that ATXN2L absence triggers mid-gestational embryonic lethality, affecting female animals more strongly. Weight and development stages of homozygous mutants were reduced. Placenta phenotypes were not apparent, but brain histology showed lamination defects and apoptosis. Aged heterozygotes showed no locomotor deficits or weight loss over 12 months. Null mutants in vivo displayed compensatory efforts to maximize Atxn2l expression, which were prevented upon nutrient abundance in vitro. Mouse embryonal fibroblast cells revealed more multinucleated giant cells upon ATXN2L deficiency. In addition, in human neural cells, transcript levels of ATXN2L were induced upon starvation and glucose and amino acids exposure, but this induction was partially prevented by serum or low cholesterol administration. Neither ATXN2L depletion triggered dysregulation of ATXN2, nor a converse effect was observed. Overall, this essential role of ATXN2L for embryogenesis raises questions about its role in neurodegenerative diseases and neuroprotective therapies.


Asunto(s)
Pérdida del Embrión/genética , Eliminación de Gen , Ratones/embriología , Animales , Sistemas CRISPR-Cas , Línea Celular , Pérdida del Embrión/patología , Femenino , Regulación del Desarrollo de la Expresión Génica , Humanos , Ratones/genética , Embarazo
11.
Histopathology ; 67(3): 378-85, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25659413

RESUMEN

AIMS: The aims of this study were to investigate whether succinate dehydrogenase B (SDHB), insulin growth factor 1 receptor (IGF1R), HER2, epidermal growth factor receptor (EGFR) and/or BRAF V600E immunohistochemistry could screen for wild-type gastrointestinal stromal tumours (GISTs), and to determine what proportion of wild-type GISTs expressed these proteins and might therefore represent candidates for targeted therapies. METHODS AND RESULTS: Twenty-seven wild-type GISTs and 91 KIT-mutated or PDGFRA-mutated GISTs were immunostained for SDHB, IGF1R, HER2, and EGFR. A preliminary study of the BRAF VE1 antibody showed non-specific staining, and indicated it was neither a specific nor a sensitive marker of wild-type GISTs. SDHB loss showed 100% specificity but only 37% sensitivity as such a marker. EGFR and IGF1R were expressed by 63% and 33% of the wild-type GISTs but also by 56% and 32% of the KIT/PDGFRA mutant GISTs, respectively. Therefore, adding EGFR and/or IGF1R to SDHB as a panel only decreased the specificity of SDHB loss as a marker for wild-type status. CONCLUSIONS: All five antibodies failed, individually or collectively, to represent highly sensitive and highly specific markers for wild-type GIST. However, whereas HER2 has been excluded as a therapeutic biomarker, both EGFR and IGF1R are expressed by some wild-type GISTs and are therefore potential therapeutic targets.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias Gastrointestinales/metabolismo , Tumores del Estroma Gastrointestinal/metabolismo , Adolescente , Adulto , Anciano , Biomarcadores de Tumor/genética , Receptores ErbB/metabolismo , Femenino , Neoplasias Gastrointestinales/diagnóstico , Neoplasias Gastrointestinales/terapia , Tumores del Estroma Gastrointestinal/diagnóstico , Tumores del Estroma Gastrointestinal/terapia , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Terapia Molecular Dirigida , Mutación , Proteínas Proto-Oncogénicas B-raf/metabolismo , Receptor ErbB-2/metabolismo , Receptor IGF Tipo 1 , Receptores de Somatomedina/metabolismo , Succinato Deshidrogenasa/metabolismo , Adulto Joven
12.
Life (Basel) ; 14(8)2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39202670

RESUMEN

In Germany, there is currently no official guideline for the submission of placentas for histopathological examination. Placentas are sent for histological examination by obstetricians according to locally defined indications, which leads to different practices in different centers. In this study, two cohorts of placentas were compared to assess the clinical relevance of placental examination. One cohort consisted of placentas with a clinical indication for histologic examination and the other of placentas with a clinically healthy pregnancy and a healthy infant. In this study, a placenta request form based on established international guidelines was used. Placentas from singleton and twin pregnancies with and without clinical indications were histopathologically examined. Clinical information was extracted from the request form and later correlated with histological findings. A total of 236 placentas were examined, including 127 (53.8%) with clinical indications and 109 (46.2%) without. The concordance between submission reasons and histopathological findings was higher in singleton pregnancies with clinical indications (90.9%) compared to twin pregnancies (62.97%). Placentas from singleton and twin pregnancies with clinical indications exhibited significantly more pathological findings than their respective healthy control groups. Histopathological examination of the placenta can confirm or reveal placenta pathologies and therefore improve the care of the mother, child and future pregnancies.

13.
Curr Res Transl Med ; 72(4): 103463, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39278153

RESUMEN

BACKGROUND: The setting of normovolemic anemia is required for a variety of research applications, such as testing of novel medication for anemia treatment. Unfortunately, large animal models using full blood draw and replenishment with balanced electrolyte solution (BES) lead to bleeding complications, as coagulation factors and platelets are also drawn. We therefore aimed to establish a model of selective red blood cell (RBC) depletion to the main endpoint of hemoglobin (Hgb) levels of 4-6 g dL-1 using apheresis in sheep. METHODS: In vitro experiments were performed first to establish the apheresis protocol. In vivo, anesthetized ewes underwent a sham protocol without apheresis (n = 5) or apheresis (n = 4). Both groups were observed for the following six hours at a defined starting point (BE0) to compare Hgb, hematocrit (Hct), coagulation and clinical parameters. For statistical analysis, unpaired t-test with Welch`s correction was used. RESULTS: Hgb levels were effectively decreased by 51 % to mean Hgb of 4.4 g dL-1 in the apheresis group compared to 9.1 g dL-1 in sham (*p < 0.0001). Hct (11.2% vs 25.1 %, *p = 0.01) and RBCs (3.7 vs 8.2 × 106/µl, *p = 0.003) also decreased. The relative number of platelets compared to baseline was different (55.6 ± 10.6% vs. 100 ± 0 %, *p = 0.004), but no hemorrhage was observed. White blood cells (WBCs), lactate, prothrombin ratio and activated partial thromboplastin time (aPTT) remained within similar ranges. CONCLUSIONS: Critical normovolemic anemia without bleeding complications was successfully reached by selective RBC depletion in sheep. Investigations of physiological adaptations to severe anemia and pharmaceutical testing can be performed in large animals with depleted RBCs.

14.
Blood Adv ; 8(11): 2870-2879, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38588481

RESUMEN

ABSTRACT: Hemojuvelin (HJV) is a glycosylphosphatidylinositol-anchored protein of the repulsive guidance molecule family acting as a bone morphogenetic protein (BMP) coreceptor to induce the hepatic iron regulatory protein hepcidin. Hepcidin causes ubiquitination and degradation of the sole known iron exporter ferroportin, thereby limiting iron availability. The detailed signaling mechanism of HJV in vivo has yet to be investigated. In the current manuscript, we used an established model of adeno-associated virus (AAV)-mediated liver-specific overexpression of HJV in murine models of hepatocyte-specific deficiency of the BMP type I receptors Alk2 or Alk3. In control mice, HJV overexpression increased hepatic Hamp messenger RNA (mRNA) levels, soluble HJV (sHJV), splenic iron content (SIC), as well as phosphorylated small mothers against decapentaplegic protein (pSMAD1/5/8) levels. In contrast, in Alk2fl/fl;Alb-Cre and Alk3fl/fl;Alb-Cre mice, which present with moderate and severe iron overload, respectively, the administration of AAV-HJV induced HJV and sHJV. However, it did not rescue the iron overload phenotypes of those mice. Serum iron levels were induced in Alk2fl/fl;Alb-Cre mice after HJV overexpression. In phosphate-buffered saline-injected Alk3fl/fl;Alb-Cre mice, serum iron levels and the expression of duodenal ferroportin remained high, whereas Hamp mRNA levels were decreased to 1% to 5% of the levels detected in controls. This was reduced even further by AAV-HJV overexpression. SIC remained low in mice with hepatocyte-specific Alk2 or Alk3 deficiency, reflecting disturbed iron homeostasis with high serum iron levels and transferrin saturation and an inability to induce hepcidin by HJV overexpression. The data indicate that ALK2 and ALK3 are both required in vivo for the HJV-mediated induction of hepcidin.


Asunto(s)
Proteínas Ligadas a GPI , Proteína de la Hemocromatosis , Hepcidinas , Animales , Ratones , Proteínas Ligadas a GPI/metabolismo , Proteínas Ligadas a GPI/genética , Hepcidinas/metabolismo , Hepcidinas/genética , Proteína de la Hemocromatosis/metabolismo , Proteína de la Hemocromatosis/genética , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/metabolismo , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/genética , Hígado/metabolismo , Hierro/metabolismo , Sobrecarga de Hierro/metabolismo , Sobrecarga de Hierro/genética , Receptores de Activinas Tipo I/metabolismo , Receptores de Activinas Tipo I/genética , Receptores de Activinas Tipo II
15.
Nat Commun ; 15(1): 7939, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261458

RESUMEN

Acinetobacter baumannii is a pathogenic and multidrug-resistant Gram-negative bacterium that causes severe nosocomial infections. To better understand the mechanism of pathogenesis, we compare the proteomes of uninfected and infected human cells, revealing that transcription factor FOS is the host protein most strongly induced by A. baumannii infection. Pharmacological inhibition of FOS reduces the cytotoxicity of A. baumannii in cell-based models, and similar results are also observed in a mouse infection model. A. baumannii outer membrane vesicles (OMVs) are shown to activate the aryl hydrocarbon receptor (AHR) of host cells by inducing the host enzyme tryptophan-2,3-dioxygenase (TDO), producing the ligand kynurenine, which binds AHR. Following ligand binding, AHR is a direct transcriptional activator of the FOS gene. We propose that A. baumannii infection impacts the host tryptophan metabolism and promotes AHR- and FOS-mediated cytotoxicity of infected cells.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Quinurenina , Receptores de Hidrocarburo de Aril , Receptores de Hidrocarburo de Aril/metabolismo , Receptores de Hidrocarburo de Aril/genética , Acinetobacter baumannii/metabolismo , Acinetobacter baumannii/genética , Acinetobacter baumannii/efectos de los fármacos , Humanos , Animales , Ratones , Infecciones por Acinetobacter/microbiología , Infecciones por Acinetobacter/metabolismo , Quinurenina/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-fos/genética , Triptófano/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Interacciones Huésped-Patógeno
16.
Clin Res Cardiol ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748206

RESUMEN

BACKGROUND: Approximately one-third of sudden cardiac deaths in the young (SCDY) occur due to a structural cardiac disease. Forty to fifty percent of SCDY cases remain unexplained after autopsy (including microscopic and forensic-toxicological analyses), suggesting arrhythmia syndromes as a possible cause of death. Due to the possible inheritability of these diseases, blood relatives of the deceased may equally be carriers of the causative genetic variations and therefore may have an increased cardiac risk profile. A better understanding of the forensic, clinical, and genetic data might help identify a subset of the general population that is at increased risk of sudden cardiac death. STUDY DESIGN: The German registry RESCUED (REgistry for Sudden Cardiac and UnExpected Death) comprises information about SCDY fatalities and clinical and genetic data of both the deceased and their biological relatives. The datasets collected in the RESCUED registry will allow for the identification of leading causes of SCDY in Germany and offer unique possibilities of scientific analyses with the aim of detecting unrecognized trends, risk factors, and clinical warning signs of SCDY. In a pilot phase of 24 months, approximately 180 SCDY cases (< 50 years of age) and 500 family members and clinical patients will be included. CONCLUSION: RESCUED is the first registry in Germany collecting comprehensive data of SCDY cases and clinical data of the biological relatives reviewed by cardiac experts. RESCUED aims to improve individual risk assessment and public health approaches by directing resources towards early diagnosis and evidence-based, personalized therapy and prevention in affected families. Trial registration number (TRN): DRKS00033543.

18.
Front Cardiovasc Med ; 10: 1104019, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37063955

RESUMEN

Introduction: Inducible nitric oxide synthase (iNOS) produces micromolar amounts of nitric oxide (NO) upon the right stimuli, whose further reactions can lead to oxidative stress. In murine models of myocardial infarction (MI), iNOS is known to be expressed in infiltrating macrophages, which at early onset enter the infarcted zone and are associated with inflammation. In contrast cardiac tissue resident macrophages are thought to enhance regeneration of tissue injury and re-establish homeostasis. Both detrimental and beneficial effects of iNOS have been described, still the role of iNOS in MI is not fully understood. Our aim was to examine cell expression patterns of iNOS and nitrotyrosine (NT) production in human MI. Material and Methods: We examined in postmortem human MI hearts the iNOS mRNA expression by means of qPCR. Further we performed immunohistochemical stainings for cell type identification. Afterwards a distance analysis between iNOS and NT was carried out to determine causality between iNOS and NT production. Results: iNOS mRNA expression was significantly increased in infarcted regions of human MI hearts and iNOS protein expression was detected in resident macrophages in infarcted human hearts as well as in controls hearts, being higher in resident macrophages in MI hearts compared to control. Furthermore in MI and in healthy human hearts cells showing signs of NT production peaked within 10-15 µm proximity of iNOS+ cells. Discussion: These results indicate that, unexpectedly, resident macrophages are the main source of iNOS expression in postmortem human MI hearts. The peak of NT positive cells within 10-15 µm of iNOS+ cells suggest an iNOS dependent level of NT and therefore iNOS dependent oxidative stress. Our results contribute to understanding the role of iNOS in human MI.

19.
Forensic Sci Int Genet ; 65: 102867, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37178622

RESUMEN

Cardiovascular diseases are the most common causes of death worldwide. Cardiac death can occur as reaction to myocardial infarction (MI). A diagnostic challenge arises for sudden unexpected death (SUD) cases with structural abnormalities (SA) or without any structural abnormalities (without SA). Therefore, the identification of reliable biomarkers to differentiate cardiac cases from each other is necessary. In the current study, the potential of different microRNAs (miRNAs) as biomarkers in tissue and blood samples of cardiac death cases was analyzed. Blood and tissue samples of 24 MI, 21 SUD and 5 control (C) cases were collected during autopsy. Testing for significance and receiver operating characteristic analysis (ROC) were performed. The results show that miR-1, miR-133a and miR-26a possess a high diagnostic power to discriminate between different cardiac death causes in whole blood and in tissue.


Asunto(s)
Muerte Súbita Cardíaca , MicroARNs , Infarto del Miocardio , Humanos , Autopsia , Biomarcadores , MicroARNs/genética , Infarto del Miocardio/genética , Infarto del Miocardio/diagnóstico
20.
Front Immunol ; 14: 1228894, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37662907

RESUMEN

Introduction: Metastatic rhabdomyosarcoma (RMS) is a challenging tumor entity that evades conventional treatments and endogenous antitumor immune responses, highlighting the need for novel therapeutic strategies. Applying chimeric antigen receptor (CAR) technology to natural killer (NK) cells may offer safe, effective, and affordable therapies that enhance cancer immune surveillance. Methods: Here, we assess the efficacy of clinically usable CAR-engineered NK cell line NK-92/5.28.z against ErbB2-positive RMS in vitro and in a metastatic xenograft mouse model. Results: Our results show that NK-92/5.28.z cells effectively kill RMS cells in vitro and significantly prolong survival and inhibit tumor progression in mice. The persistence of NK-92/5.28.z cells at tumor sites demonstrates efficient antitumor response, which could help overcome current obstacles in the treatment of solid tumors. Discussion: These findings encourage further development of NK-92/5.28.z cells as off-the-shelf immunotherapy for the treatment of metastatic RMS.


Asunto(s)
Neoplasias Primarias Secundarias , Receptores Quiméricos de Antígenos , Rabdomiosarcoma Alveolar , Rabdomiosarcoma , Humanos , Animales , Ratones , Rabdomiosarcoma Alveolar/terapia , Receptores Quiméricos de Antígenos/genética , Inmunoterapia , Rabdomiosarcoma/terapia , Modelos Animales de Enfermedad , Células Asesinas Naturales
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