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1.
Am J Transplant ; 22(2): 519-531, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34455702

RESUMEN

Graft survival beyond year 1 has not changed after orthotopic liver transplantation (OLT) over the last decades. Likewise, OLT causes comorbidities such as infection, renal impairment and cancer. We evaluated our single-center real-world individualized immunosuppression program after OLT, based on 211 baseline surveillance biopsies (svLbx) without any procedural complications. Patients were classified as low, intermediate and high rejection risk based on graft injury in svLbx and anti-HLA donor-specific antibodies. While 32% of patients had minimal histological inflammation, 57% showed histological inflammation and 23% advanced fibrosis (>F2), which was not predicted by lab parameters. IS was modified in 79% of patients after svLbx. After immunosuppression reduction in 69 patients, only 5 patients showed ALT elevations and three of these patients had a biopsy-proven acute rejection, two of them related to lethal comorbidities. The rate of liver enzyme elevation including rejection was not significantly increased compared to a svLbx control cohort prior to the initiation of our structured program. Immunosuppression reduction led to significantly better kidney function compared to this control cohort. In conclusion, a biopsy guided personalized immunosuppression protocol after OLT can identify patients requiring lower immunosuppression or patients with graft injury in which IS should not be further reduced.


Asunto(s)
Trasplante de Hígado , Biopsia , Rechazo de Injerto/patología , Supervivencia de Injerto , Humanos , Terapia de Inmunosupresión , Inmunosupresores/uso terapéutico , Trasplante de Hígado/efectos adversos
2.
Z Gastroenterol ; 59(2): 149-152, 2021 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-33556974

RESUMEN

We report the case of a 62-year-old Caucasian male patient who presented with epigastric pain to our outpatient clinic. On abdominal ultrasound we detected a 26 mm oval hypoechoic lesion in segment 2 of the left liver lobe. Performing contrast-enhanced ultrasound this lesion showed an arterial hypervascularization with centripetal filling and a spoke wheel pattern. Due to a hyperenhancement during the portal and late phase this lesion led to the diagnosis of a benign liver tumor, probably a hepatocellular adenoma (HCA). As focal nodular hyperplasia (FNH) was still another possible diagnosis, we decided to perform an MRI, which could not differentiate between HCA and hepatocellular carcinoma (HCC). Therefore, we performed liver biopsy of this lesion. Histology and immunohistochemistry led to the final diagnosis of intrahepatic splenosis. Reassessment of patient history revealed an abdominal trauma with splenic rupture 5 years ago. Intrahepatic splenosis should be considered as an important differential diagnosis in patients with unknown liver tumor and a history of splenic trauma.


Asunto(s)
Imagen por Resonancia Magnética , Esplenosis/patología , Abdomen/diagnóstico por imagen , Adenoma de Células Hepáticas , Carcinoma Hepatocelular , Medios de Contraste , Diagnóstico Diferencial , Humanos , Hígado/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Ultrasonografía/métodos
3.
Am J Physiol Renal Physiol ; 306(8): F907-15, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24573392

RESUMEN

The aging kidney has a diminished regenerative potential and an increased tendency to develop tubular atrophy and fibrosis after acute injury. In this study, we found that activation of tubular epithelial Notch1 signaling was prolonged in the aging kidney after ischemia/reperfusion (IR) damage. To analyze the consequences of sustained Notch activation, we generated mice with conditional inducible expression of Notch1 intracellular domain (NICD) in proximal tubules. NICD kidneys were analyzed 1 and 4 wk after renal IR. Conditional NICD expression was associated with aggravated tubular damage, a fibrotic phenotype, and the expression of cellular senescence markers p21 and p16(INK4a). In wild-type mice pharmacological inhibition of Notch using the γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester (DAPT) improved tubulo-interstitial damage and antagonized the prosenescent pathway activation after IR. In vitro, activation of Notch signaling with delta-like-ligand-4 caused prosenescent changes in tubular cells while inhibition with DAPT attenuated these changes. In conclusion, our data suggest that sustained epithelial Notch activation after IR might contribute to the inferior outcome of old kidneys after injury. Sustained epithelial activation of Notch is associated with a prosenescent phenotype and maladaptive repair.


Asunto(s)
Lesión Renal Aguda/fisiopatología , Receptor Notch1/fisiología , Proteínas Adaptadoras Transductoras de Señales , Envejecimiento , Animales , Proteínas de Unión al Calcio , Senescencia Celular/efectos de los fármacos , Dipéptidos/farmacología , Fibrosis , Péptidos y Proteínas de Señalización Intracelular/farmacología , Túbulos Renales/metabolismo , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/patología , Masculino , Proteínas de la Membrana/farmacología , Ratones , Ratones Endogámicos C57BL , Receptor Notch1/biosíntesis , Daño por Reperfusión/patología , Daño por Reperfusión/fisiopatología
4.
Med Ultrason ; 25(1): 14-21, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36780599

RESUMEN

AIMS: Cholecystitis generally warrants immediate cholecystectomy; however, high-risk patients require non-surgical options for gallbladder decompression. The continuous evolution of endoscopic techniques makes it difficult for clinicians tochoose the best technique for high-risk patients. Here we aimed to show that percutaneous transhepatic gallbladder aspiration, a technique that has fallen into disuse, is a safe and rapid method for gallbladder decompression. MATERIALS AND METHODS: In our local database, we identified 48 patients who had undergone transhepatic punctures of the biliary system,34 of whom were excluded because they had received bile duct punctures. The remaining 14 patients had received gallbladder punctures, of whom 9 were considered eligible for analysis. Cases were retrospectively analyzed for technical success, complications, and individual outcomes. RESULTS: Our analysis included 9 patients (3 female, 6 male; median age, 51 years; range, 32-84 years). Underlying malignancy was found in 5 patients, while 4 were in a palliative situation. Underlying infection was found in 8 cases. All punctures were technically successful without complications. In all patients, individual therapy goals were met,including clinical stabilization in palliative situations, stabilization before liver surgery, exclusion of gallbladder empyema and infection in gallbladder hydrops, and avoidance of gallbladder rupture. The white blood cell counts at the day of punction were significantly reduced one week after the puncture (p=0.023). CONCLUSIONS: When selecting an appropriate technique for high-risk patients, clinicians should remember that gallbladder aspiration is a feasible and successful bedside procedure in patients at high surgical risk, which does not require an experienced endoscopist.


Asunto(s)
Colecistitis , Enfermedades de la Vesícula Biliar , Humanos , Masculino , Femenino , Persona de Mediana Edad , Vesícula Biliar/diagnóstico por imagen , Vesícula Biliar/cirugía , Estudios Retrospectivos , Drenaje/métodos , Ultrasonografía Intervencional , Descompresión , Resultado del Tratamiento
5.
Front Transplant ; 2: 1148195, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38993851

RESUMEN

Background: Liver stiffness measurements (LSMs) have proven useful for non-invasive detection of fibrosis. Previous studies of LSMs after transplantation were performed in cohorts dominated by hepatitis C reinfections and indication biopsies for the evaluation of graft dysfunction. However, the diagnostic fidelity of LSMs for fibrosis is biased by inflammation e.g., during replicative hepatitis C or rejection. Materials and methods: The current study aimed for a head-to-head comparison of two different LSMs, acoustic radiation force impulse (ARFI) and transient elastography (TE), and a determination of cut-off values for the detection of advanced fibrosis (any LAF score component ≥2) in grafts undergoing surveillance biopsies (svLbx) without recurrent hepatitis C. Results: 103 svLbx were paired with valid LSMs at time of biopsy. AUROC analyses showed significant positive correlation with fibrosis for both methods (TE: AUROC = 0.819 (p < 0.001; 95%CI: 0.717-0.921); ARFI: AUROC = 0.771 (p = 0.001; 95%CI: 0.652-0.890). Patients were randomly assigned to training and validation cohorts for both LSM methods. Cut-off values were determined at 1.29 m/s (ARFI) and at 7.5 kPa (TE) in training cohorts. Sensitivity and specificity in training and validation cohorts were: TE: SEN 0.818 and 0.5; SPE 0.742 and 0.885; ARFI: SEN 0.818 and 1.0; SPE 0.75 and 0.586. LSMs were not associated with BANFF criteria for relevant graft injury. Conclusion: LSM is a good non-invasive tool to screen for advanced graft fibrosis but not for relevant graft injury in patients with (near) normal liver enzymes. Fibrosis cut-off values identified and validated in svLbx were lower than in previous cohorts using indication biopsies.

6.
Cardiol J ; 25(1): 32-41, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29168543

RESUMEN

BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9)-inhibitors have shown great po-tential in efficient lipid lowering to achieve low-density lipoprotein-cholesterol (LDL-C) treatment goals. The aim of the study was too describe the clinical use of PCSK9-inhibitors and to investigate therapy adherence and safety outside of clinical trials. METHODS: Thirty-eight patients were treated with PSCK9-inhibitors. Patients were eligible for this therapy based on their individual cardiovascular risk and when all other available lipid-lowering regi-men had failed. Every patient answered a questionnaire concerning medical history and relevant side effects and therapy adherence. RESULTS: Conventional therapy reduced patient LDL-C levels by about 38%. However, in 26 of the 38 patients, LDL-C treatment goals were not fulfilled because patients did not tolerate further dose es-calation due to side effects. Using a PCSK9 inhibitor, LDL-C levels were reduced by another 54% and 42% of patients reaching treatment goals. The results show that most patients still require concomitant therapy to reach LDL-C target levels. Three patients required dose reduction or change of the PCSK9 inhibitor. 16% did not inject the PCSK9 inhibitor regularly. CONCLUSIONS: Only a minority of patients reached the recommended LDL-C goals. PCSK9-inhibitors were generally well tolerated. Despite low rates of reported side effects, therapy adherence was incom-plete, with 6 patients not injecting PCSK9-inhibitors on a regular basis. In-depth information about the medication and close supervision is advisable. PCSK9 inhibitors have shown great potential in aggressive lipid lowering therapy, but basic therapy is still required in most cases. Close supervision is recommended to improve therapy adherence. (Cardiol J 2018; 25, 1: 32-41).


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Hipercolesterolemia/tratamiento farmacológico , Inhibidores de PCSK9 , Cumplimiento y Adherencia al Tratamiento , Anticuerpos Monoclonales Humanizados , Anticolesterolemiantes/uso terapéutico , Apoptosis , Estudios de Cohortes , Femenino , Humanos , Hipercolesterolemia/sangre , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Encuestas y Cuestionarios , Resultado del Tratamiento
7.
Front Med (Lausanne) ; 4: 87, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28691008

RESUMEN

Whipple's disease (WD) is a rare chronic systemic infection with a wide range of clinical symptoms, routinely diagnosed in biopsies from the small intestine and other tissues by periodic acid-Schiff (PAS) diastase staining and immunohistological analysis with specific antibodies. The aim of our study was to improve the pathological diagnosis of WD. Therefore, we analyzed the potential of fluorescence in situ hybridization (FISH) for diagnosing WD, using a Tropheryma (T.) whipplei-specific probe. 19 formalin-fixed paraffin-embedded (FFPE) duodenal biopsy specimens of 12 patients with treated (6/12) and untreated (6/12) WD were retrospectively examined using PAS diastase staining, immunohistochemistry, and FISH. 20 biopsy specimens with normal intestinal mucosa, Helicobacter pylori, or mycobacterial infection, respectively, served as controls. We successfully detected T. whipplei in tissue biopsies with a sensitivity of 83% in untreated (5/6) and 40% in treated (4/10) cases of WD. In our study, we show that FISH-based diagnosis of individual vital T. whipplei in FFPE specimens is feasible and can be considered as ancillary diagnostic tool for the diagnosis of WD in FFPE material. We show that FISH not only detect active WD but also be helpful as an indicator for the efficiency of antibiotic treatment and for detection of recurrence of disease when the signal of PAS diastase and immunohistochemistry lags behind the recurrence of disease, especially if the clinical course of the patient and antimicrobial treatment is considered.

9.
PLoS One ; 11(9): e0162673, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27649309

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0095605.].

10.
PLoS One ; 9(4): e95605, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24748170

RESUMEN

UNLABELLED: Capsaicin, the most abundant pungent molecule produced by pepper plants, represents an important ingredient in spicy foods consumed throughout the world. Studies have shown that capsaicin can relieve inflammation and has anti-proliferative effects on various human malignancies. Cholangiocarcinoma (CC) is a cancer disease with rising incidence. The prognosis remains dismal with little advance in treatment. The aim of the present study is to explore the anti-tumor activity of capsaicin in cultured human CC cell lines. Capsaicin effectively impaired cell proliferation, migration, invasion, epithelial to mesenchymal transition and growth of softagar colonies. Further, we show that capsaicin treatment of CC cells regulates the Hedgehog signaling pathway. CONCLUSION: Our results provide a basis for capsaicin to improve the prognosis of CCs in vivo and present new insights into the effectiveness and mode of action of capsaicin.


Asunto(s)
Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/patología , Capsaicina/farmacología , Transformación Celular Neoplásica/efectos de los fármacos , Colangiocarcinoma/patología , Apoptosis/efectos de los fármacos , Neoplasias de los Conductos Biliares/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colangiocarcinoma/metabolismo , Transición Epitelial-Mesenquimal/efectos de los fármacos , Proteínas Hedgehog/metabolismo , Humanos , Transducción de Señal/efectos de los fármacos , Ensayo de Tumor de Célula Madre
11.
BMC Res Notes ; 6: 331, 2013 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-23958171

RESUMEN

BACKGROUND: Adrenocorticotropic hormone-producing extraadrenal paragangliomas are extremely rare. We present a case of severe hypercortisolemia due to ectopic adrenocorticotropic hormone secretion by a nasal paraganglioma. CASE PRESENTATION: A 70-year-old Caucasian woman, was emergently admitted to our department with supraventricular tachycardia, oedema of face and extremities and hypertensive crisis. Initial laboratory evaluation revealed severe hypokalemia and hyperglycemia without ketoacidosis, although no diabetes mellitus was previously known. Computed tomography revealed a large tumor obliterating the left paranasal sinus and a left-sided adrenal mass. After cardiovascular stabilisation, a thorough hormonal assessment was performed revealing marked adrenocorticotropic hormone-dependent hypercortisolism. Due to the presence of a cardiac pacemaker magnetic resonance imaging of the hypophysis was not possible. [68Ga-DOTA]-TATE-Positron-Emission-Tomography was performed, showing somatostatin-receptor expression of the paranasal lesion but not of the adrenal lesion or the hypophysis. The paranasal tumor was resected and found to be an adrenocorticotropic hormone-producing paraganglioma of low-proliferative rate. Postoperatively the patient became normokaliaemic, normoglycemic and normotensive without further need for medication. Genetic testing showed no mutation of the succinatdehydrogenase subunit B- and D genes, thus excluding hereditary paragangliosis. CONCLUSION: Detection of the adrenocorticotropic hormone source in Cushing's syndrome can prove extremely challenging, especially when commonly used imaging modalities are unavailable or inconclusive. The present case was further complicated by the simultaneous detection of two tumorous lesions of initially unclear biochemical behaviour. In such cases, novel diagnostic tools - such as somatostatin-receptor imaging - can prove useful in localising hormonally active neuroendocrine tissue. The clinical aspects of the case are discussed and relevant literature is reviewed.


Asunto(s)
Síndrome de ACTH Ectópico/etiología , Hormona Adrenocorticotrópica/sangre , Síndrome de Cushing/etiología , Hidrocortisona/sangre , Neoplasias Nasales/complicaciones , Paraganglioma Extraadrenal/complicaciones , Síndrome de ACTH Ectópico/sangre , Síndrome de ACTH Ectópico/diagnóstico , Síndrome de ACTH Ectópico/terapia , Hormona Adrenocorticotrópica/metabolismo , Anciano , Biomarcadores/sangre , Síndrome de Cushing/sangre , Síndrome de Cushing/diagnóstico , Síndrome de Cushing/terapia , Femenino , Humanos , Neoplasias Nasales/sangre , Neoplasias Nasales/diagnóstico , Neoplasias Nasales/metabolismo , Neoplasias Nasales/cirugía , Compuestos Organometálicos , Paraganglioma Extraadrenal/sangre , Paraganglioma Extraadrenal/diagnóstico , Paraganglioma Extraadrenal/metabolismo , Paraganglioma Extraadrenal/cirugía , Tomografía de Emisión de Positrones , Radiofármacos , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
12.
Cancer Cell ; 23(6): 784-95, 2013 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-23727022

RESUMEN

The incidence of cholangiocellular carcinoma (CCC) is increasing worldwide. Using a transgenic mouse model, we found that expression of the intracellular domain of Notch 1 (NICD) in mouse livers results in the formation of intrahepatic CCCs. These tumors display features of bipotential hepatic progenitor cells, indicating that intrahepatic CCC can originate from this cell type. We show that human and mouse CCCs are characterized by high expression of the cyclin E protein and identified the cyclin E gene as a direct transcriptional target of the Notch signaling pathway. Intriguingly, blocking γ-secretase activity in human CCC xenotransplants results in downregulation of cyclin E expression, induction of apoptosis, and tumor remission in vivo.


Asunto(s)
Colangiocarcinoma/genética , Regulación Neoplásica de la Expresión Génica , Receptor Notch1/genética , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Animales , Apoptosis/genética , Proliferación Celular , Colangiocarcinoma/patología , Ciclina E/genética , Ciclina E/metabolismo , Regulación hacia Abajo , Hepatocitos/citología , Humanos , Hígado/metabolismo , Ratones , Ratones Transgénicos , Receptor Notch1/química , Receptor Notch1/metabolismo , Transducción de Señal , Trasplante Heterólogo
14.
Cancer Cell ; 14(1): 23-35, 2008 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-18598941

RESUMEN

A reduction in the cellular levels of the cyclin kinase inhibitor p27(kip1) is frequently found in many human cancers and correlates directly with patient prognosis. In this work, we identify argyrin A, a cyclical peptide derived from the myxobacterium Archangium gephyra, as a potent antitumoral drug. All antitumoral activities of argyrin A depend on the prevention of p27(kip1) destruction, as loss of p27(kip1) expression confers resistance to this compound. We find that argyrin A exerts its effects through a potent inhibition of the proteasome. By comparing the cellular responses exerted by argyrin A with siRNA-mediated knockdown of proteasomal subunits, we find that the biological effects of proteasome inhibition per se depend on the expression of p27(kip1).


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Inhibidores de Cisteína Proteinasa/farmacología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias/tratamiento farmacológico , Péptidos Cíclicos/farmacología , Inhibidores de Proteasoma , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Vasos Sanguíneos/efectos de los fármacos , Vasos Sanguíneos/patología , Ácidos Borónicos/farmacología , Bortezomib , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Relación Dosis-Respuesta a Droga , Células HCT116 , Células HeLa , Humanos , Ratones , Ratones Desnudos , Necrosis , Neoplasias/irrigación sanguínea , Neoplasias/enzimología , Neoplasias/patología , Neovascularización Patológica/enzimología , Neovascularización Patológica/prevención & control , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Pirazinas/farmacología , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Factores de Tiempo , Transfección , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Cell Div ; 2: 13, 2007 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-17488529

RESUMEN

The cyclin kinase inhibitor p27kip1 acts as a potent tumor supressor protein in a variety of human cancers. Its expression levels correlate closely with the overall prognosis of the affected patient and often predict the outcome to different treatment modalities. In contrast to other tumor suppressor proteins p27 expression levels in tumor cells are frequently regulated by ubiquitin dependent proteolysis. Re-expression of p27 in cancer cells therefore does not require gene therapy but can be achieved by interfering with the protein turnover machinery. In this review we will summarize experimental results which highlight the potential use of p27 as a target for oncological therapies.

16.
Proc Natl Acad Sci U S A ; 100(13): 7797-802, 2003 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-12810955

RESUMEN

A major concern in therapy of acute liver failure is protection of hepatocytes to prevent apoptosis and maintain liver function. Small interfering RNA (siRNA) is a powerful tool to silence gene expression in mammalian cells. To evaluate the therapeutic efficacy of siRNA in vivo we used different mouse models of acute liver failure. We directed 21-nt siRNAs against caspase 8, which is a key enzyme in death receptor-mediated apoptosis. Systemic application of caspase 8 siRNA results in inhibition of caspase 8 gene expression in the liver, thereby preventing Fas (CD95)-mediated apoptosis. Protection of hepatocytes by caspase 8 siRNA significantly attenuated acute liver damage induced by agonistic Fas (CD95) antibody (Jo2) or by adenovirus expressing Fas ligand (AdFasL). However, in a clinical situation the siRNAs most likely would be applied after the onset of acute liver failure. Therefore we injected caspase 8 siRNA at a time point during AdFasL- and adenovirus wild type (Adwt)-mediated liver failure with already elevated liver transaminases. Improvement of survival due to RNA interference was significant even when caspase 8 siRNA was applied during ongoing acute liver failure. In addition, it is of particular interest that caspase 8 siRNA treatment was successful not only in acute liver failure mediated by specific Fas agonistic agents (Jo2 and AdFasL) but also in acute liver failure mediated by Adwt, which is an animal model reflecting multiple molecular mechanisms involved in human acute viral hepatitis. Consequently, our data raise hope for future successful application of siRNA in patients with acute liver failure.


Asunto(s)
Caspasas/genética , Fallo Hepático/prevención & control , Hígado/patología , ARN Interferente Pequeño/genética , Enfermedad Aguda , Adenoviridae/genética , Animales , Apoptosis , Northern Blotting , Caspasa 8 , Caspasa 9 , Línea Celular , Proteína Ligando Fas , Regulación de la Expresión Génica/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Glicoproteínas de Membrana/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Factores de Tiempo , Transfección , Células Tumorales Cultivadas , Receptor fas/metabolismo
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