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1.
Phys Rev Lett ; 131(3): 031802, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37540851

RESUMEN

We report the direct observation of muon neutrino interactions with the SND@LHC detector at the Large Hadron Collider. A dataset of proton-proton collisions at sqrt[s]=13.6 TeV collected by SND@LHC in 2022 is used, corresponding to an integrated luminosity of 36.8 fb^{-1}. The search is based on information from the active electronic components of the SND@LHC detector, which covers the pseudorapidity region of 7.2<η<8.4, inaccessible to the other experiments at the collider. Muon neutrino candidates are identified through their charged-current interaction topology, with a track propagating through the entire length of the muon detector. After selection cuts, 8 ν_{µ} interaction candidate events remain with an estimated background of 0.086 events, yielding a significance of about 7 standard deviations for the observed ν_{µ} signal.

2.
Biochim Biophys Acta Biomembr ; 1862(8): 183291, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32234322

RESUMEN

Antimicrobial peptides (AMPs) selectively kill bacteria by disrupting their cell membranes, and are promising compounds to fight drug-resistant microbes. Biophysical studies on model membranes have characterized AMP/membrane interactions and the mechanism of bilayer perturbation, showing that accumulation of cationic peptide molecules in the external leaflet leads to the formation of pores ("carpet" mechanism). However, similar quantitative studies on real cells are extremely limited. Here, we investigated the interaction of the dansylated PMAP23 peptide (DNS-PMAP23) with a Gram-positive bacterium, showing that 107 bound peptide molecules per cell are needed to kill it. This result is consistent with our previous finding for Gram-negative strains, where a similar high threshold for killing was determined, demonstrating the general relevance of the carpet model for real bacteria. However, in the case of the Gram-positive strain, this number of molecules even exceeds the total surface available on the bacterial membrane. The high affinity of DNS-PMAP23 for the anionic teichoic acids of the Gram-positive cell wall, but not for the lipopolysaccharides of Gram-negative bacteria, provides a rationale for this finding. To better define the role of anionic lipids in peptide/cell association, we studied DNS-PMAP23 interaction with E. coli mutant strains lacking phosphatidylglycerol and/or cardiolipin. Surprisingly, these strains showed a peptide affinity similar to that of the wild type. This finding was rationalized by observing that these bacteria have an increased content of other anionic lipids, thus maintaining the total membrane charge essentially constant. Finally, studies of DNS-PMAP23 association to dead bacteria showed an affinity an order of magnitude higher compared to that of live cells, suggesting strong peptide binding to intracellular components that become accessible after membrane perturbation. This effect could play a role in population resistance to AMP action, since dead bacteria could protect the surviving cells by sequestering significant amounts of peptide molecules. Overall, our data indicate that quantitative studies of peptide association to bacteria can lead to a better understanding of the mechanism of action of AMPs.


Asunto(s)
Antibacterianos/química , Péptidos Catiónicos Antimicrobianos/química , Pared Celular/efectos de los fármacos , Relación Estructura-Actividad , Secuencia de Aminoácidos/genética , Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Membrana Celular/efectos de los fármacos , Membrana Celular/ultraestructura , Pared Celular/química , Pared Celular/ultraestructura , Bacterias Gramnegativas/química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/patogenicidad , Bacterias Grampositivas/química , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/patogenicidad , Humanos , Lipopolisacáridos/química , Pruebas de Sensibilidad Microbiana
3.
Osteoporos Int ; 28(2): 577-584, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27682249

RESUMEN

In hemodialysis patients, vertebral fractures were associated with elevated sclerostin levels, suggesting that sclerostin could reflect bone fragility in these patients. INTRODUCTION: Fragility fractures are common in hemodialysis patients. The aims of our study were to determine the prevalence of vertebral fracture and analyze associations between sclerostin serum levels and vertebral fractures in hemodialysis patients. METHODS: Ninety-two hemodialysis patients and 100 controls matched for age and sex were studied. Bone mineral density was measured by ultrasonography at non-dominant heel. The markers of bone turnover included serum osteocalcin, C-terminal telopeptide, and sclerostin. All participants underwent radiography of the thoracic and lumbar spine to ascertain the presence of vertebral fractures. RESULTS: Bone ultrasound parameters at calcaneus were significantly lower in hemodialysis patients compared with controls; bone turnover markers and parathyroid hormone level were significantly higher, while serum of 25-OH-D3 was significantly lower in hemodialysis group. One or more moderate or severe vertebral fractures were found in 38 hemodialysis patients, whereas in control group, 10 patients had a vertebral fracture. In hemodialysis group, the comparison between patients with and without vertebral fractures showed that the patients with vertebral fractures had the serum sclerostin levels statistically higher than patients without vertebral, while serum levels of 25-OH-D3 was significantly lower in patients with vertebral fractures compared to the patients without vertebral fractures. Multivariate analysis disclosed that sclerostin levels were associated with an increased risk of vertebral fractures in hemodialysis patients after adjusting for multiple variables. CONCLUSIONS: Our data shows high prevalence of vertebral fractures in hemodialysis patients and that it is associated with elevated sclerostin levels, reflecting bone fragility in these patients.


Asunto(s)
Proteínas Morfogenéticas Óseas/sangre , Fracturas Osteoporóticas/etiología , Diálisis Renal/efectos adversos , Fracturas de la Columna Vertebral/etiología , Deficiencia de Vitamina D/complicaciones , Proteínas Adaptadoras Transductoras de Señales , Anciano , Anciano de 80 o más Años , Densidad Ósea/fisiología , Estudios de Casos y Controles , Femenino , Marcadores Genéticos , Talón/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/complicaciones , Osteoporosis/diagnóstico por imagen , Osteoporosis/fisiopatología , Fracturas Osteoporóticas/sangre , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/fisiopatología , Radiografía , Medición de Riesgo/métodos , Fracturas de la Columna Vertebral/sangre , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/fisiopatología , Ultrasonografía , Calcificación Vascular/sangre , Calcificación Vascular/etiología , Deficiencia de Vitamina D/fisiopatología
4.
Med Pediatr Oncol ; 29(2): 79-85, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9180907

RESUMEN

The principal aim of this report is to present the results of multivariate analyses conducted to identify clinical prognostic factors in 92 children aged < 16 years with ependymoma (EPD) retrospectively collected in seven Italian centres. They were treated over a 16-year period (1977-1993). Treatment modalities varied. Surgery and radiotherapy (RT) was the "gold standard" management method for the majority of these children. Only in the late 1980s did some of them receive chemotherapy (CT), mainly with vincristine, lomustine (CCNU) and prednisone. The median follow-up of the entire study population is 36 months (average 43 months; range 12 to 214 months). The 10-year overall (OS) and the progression-free survival (PFS) of the study population were 55.5% (CI 41.4-69.4%) and 34.7% (CI 21.4-47.8%), respectively. Age (< 5 years; > 5 years), sex, site (infratentorial vs. supratentorial), histology (anaplastic/malignant vs. non-anaplastic/non-malignant), type of resection (complete vs. incomplete); use and fields of RT, and of CT employed were entered in a multivariate regression model to test their impact on OS and PFS. On univariate analysis, radical surgery, the use of RT and age more than 5 years at the time of diagnosis achieved statistically significant values for predicting long-term OS and PFS. Histology reached marginal statistical significance but only for PFS. When those variables were entered in a multivariate analysis only radical resection (P = 0.00142 and 0.0001) resulted a significant factor for predicting long-term OS and PFS, while the use of RT reached a marginal statistical significance, but only for PFS (P = 0.05). Children who had the tumour completely resected did significantly better than all the others who had less than a complete resection, with a 10-year OS and PFS for the two groups of patients of 69.8% (CI 53-86.5%) and 57.2% (CI 40.3-75%) and of 32.5% (CI 8.5-57.6%) and 11.1% (0-24.4%), respectively. These findings suggest that, for childhood EPD, radical resection should be pursued as much as reasonably possible. Thus, it seems justified proposing for future trials, patient stratification by entity of surgical resection.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Ependimoma/diagnóstico , Ependimoma/terapia , Adolescente , Neoplasias Encefálicas/patología , Niño , Preescolar , Ependimoma/patología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Análisis Multivariante , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento
5.
J Laryngol Otol ; 97(6): 553-6, 1983 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6864097

RESUMEN

A case report of a Stage III botryoid rhabdomyosarcoma of the nasopharynx associated with a six-and-a-half-year survival is presented. Treatment consisted of surgery, radiotherapy (6,000 rads TCT) to the nasopharynx and maxillary sinuses bilaterally, and six cycles of polychemotherapy with Vincristine, Adriamycin, Cyclophosphamide and DTIC, without major loss of function or cosmetic deformity. The histology of the lesion is discussed with reference to recent classification and prognosis. The authors suggest that the histological type and prognosis of rhabdomyosarcoma of the nasopharynx in children may be better correlated in future studies.


Asunto(s)
Neoplasias Nasofaríngeas/patología , Rabdomiosarcoma/patología , Niño , Femenino , Humanos , Neoplasias Nasofaríngeas/terapia , Pronóstico , Rabdomiosarcoma/terapia
8.
Exp Hematol ; 7(2): 74-80, 1979 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-371974

RESUMEN

A year-long double-blind study of 2,3-dihydroxybenzoic acid (2,3-DHB) given orally at a dose of 25 mg/kg four times per day was undertaken in 15 patients with beta-thalassemia major. 2,3-DHB and placebo (mannitol) were tolerated to an equal degree and there were no signs of drug toxicity at the end of 1 year. Efficacy in terms of retardation of iron accumulation could be documented using serial liver biopsies, serum ferritin determinations, or clinical laboratory assessment. Serum iron values increased, as did the iron binding capacity, in the group receiving 2,3-DHB. The increase in iron binding capacity was due to drug interference with the method of determination. Because of the greater efficacy of slow infusions of desferrioxamine in chelating iron when administered slowly, the clinic has shifted its emphasis toward further evaluation of that compound. Nevertheless, in view of the minimal toxicity of 2,3-DHB, further work appears warranted to define its role in the treatment of iron-overload.


Asunto(s)
Benzoatos/uso terapéutico , Quelantes/uso terapéutico , Talasemia/tratamiento farmacológico , Administración Oral , Adolescente , Adulto , Benzoatos/administración & dosificación , Benzoatos/efectos adversos , Quelantes/administración & dosificación , Quelantes/efectos adversos , Niño , Ensayos Clínicos como Asunto , Método Doble Ciego , Evaluación de Medicamentos , Femenino , Ferritinas/sangre , Humanos , Hierro/sangre , Hierro/metabolismo , Hígado/metabolismo , Masculino , Placebos , Talasemia/sangre , Talasemia/metabolismo , Factores de Tiempo
9.
Am J Med ; 64(4): 547-55, 1978 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-645720

RESUMEN

The heart was evaluated by echocardiography in 56 patients at risk for myocardial iron deposition. Fifty-four had congenital anemia for which they required repeated transfusions, and two had primary hemochromatosis. The data, plotted according to one of three functions of the body surface area, were compared to values obtained in 105 normal subjects whose age spanned a similar range. Left ventricular wall thickness, transverse dimension and mass, as well as left atrial transverse dimension, were increased in the majority of patients with chronic iron overload despite the infrequent occurrence of cardiac enlargement on routine chest films (32 per cent) or electrocardiographic abnormality (16 per cent). Left ventricular ejection fraction was normal in all but four patients. These four patients died within a six month follow-up period suggesting that deterioration in systolic function is an indicator of poor prognosis. Our findings indicate that echocardiography provides a simple noninvasive means for assessing changes in cardiac structure and function that should prove useful in the serial evaluation of patients who are at risk for the development of myocardial iron deposition.


Asunto(s)
Anemia/terapia , Ecocardiografía , Corazón/fisiopatología , Hierro/sangre , Miocardio/metabolismo , Reacción a la Transfusión , Adolescente , Adulto , Anemia/congénito , Cardiomiopatías/etiología , Cardiomiopatías/patología , Cardiomiopatías/fisiopatología , Niño , Preescolar , Ventrículos Cardíacos/patología , Humanos , Lactante , Hierro/metabolismo , Pronóstico , Riesgo , Talasemia
11.
Clin Pharmacol Ther ; 20(4): 476-83, 1976 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-975719

RESUMEN

Serum half-lives for antipyrine were normal or shorter than normal in 19 subjects between 7 and 23 yr of age with beta-thalassemia major. The mean antipyrine serum half life (+/-SE) for the group as a whole was 8.5 +/- 0.6 hr. The mean antipyrine half-lives (t1/2) for the younger subjects were within the range reported for normal children, while the mean t1/2 for the older males approached the values reported for normal adult males. The mean t1/2 for the older females was shorter than has been reported for normal adult females. The mean apparent volume of distribution for antipyrine (+/-SE) in the subjects with thalassemia was 0.69 +/- 0.01 L/kg. Thus, total body water appears to be increased in thalassemia. The mean metabolic clearance rate for antipyrine (+/-SE) in the group as a whole (1.07 +/- 0.08 ml/min/kg) is substantially higher than the metabolic clearance rates for antipyrine reported in normal adults. Thus, the relatively short t1/2s of antipyrine in subjects with thalassemia are attributable to rapid rates of clearance of the drug. The data indicate that antipyrine clearance is unimpaired in patients with thalassemia despite evidence of liver damage and iron overload. Our study supports the proposition that hepatic microsomal hemoprotein synthesis is not adversely affected in homozygous beta-thalassemia.


Asunto(s)
Antipirina/metabolismo , Talasemia/metabolismo , Adolescente , Adulto , Factores de Edad , Niño , Femenino , Semivida , Humanos , Masculino , Tasa de Depuración Metabólica , Análisis de Regresión , Factores Sexuales , Factores de Tiempo
12.
Br J Haematol ; 33(4): 477-85, 1976 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1009020

RESUMEN

2-3-Dihydroxybenzoic acid was evaluated as a potentially useful, orally effective iron-chelating drug by performing iron balance studies in patients with beta-thalassaemia major. The administration of this substance at 25 mg/kg/d to five patients for 8 d caused an average increase in iron excretion of 4.5 mg/d. When the drug was administered at 25 mg/kg q.i.d. to eight patients for 21 d, iron excretion increased to 6.5 mg/d. Chelation was highly specific for iron with changes in magnesium and calcium excretion being insignificant. The drug was well tolerated with side effects limited to gastrointestinal complaints which ameliorated when the drug was taken with food. These studies provide a rationale for further evaluation of 2,3-dihydroxybenzoic acid in patients with iron overload.


Asunto(s)
Quelantes/uso terapéutico , Hidroxibenzoatos/uso terapéutico , Quelantes del Hierro/uso terapéutico , Talasemia/tratamiento farmacológico , Administración Oral , Niño , Heces/análisis , Humanos , Hidroxibenzoatos/administración & dosificación , Hierro/metabolismo , Hierro/orina , Magnesio/metabolismo , Cooperación del Paciente
13.
J Bone Joint Surg Am ; 58(5): 662-6, 1976 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-932063

RESUMEN

Fractures occur frequently in patients with homozygous beta-thalassemia. A study was made of the fractures noted in a group of patients who were followed at the Thalassemia Clinic at The New York Hospital-Cornell Medical Center. Results indicate that these patients often sustain fractures which are multiple and which frequently heal with resultant deformities.


Asunto(s)
Fracturas Espontáneas/etiología , Talasemia/complicaciones , Adolescente , Adulto , Moldes Quirúrgicos , Niño , Preescolar , Femenino , Fracturas Espontáneas/terapia , Humanos , Masculino , Piel , Férulas (Fijadores) , Tracción
14.
Am J Med ; 60(7): 1032-5, 1976 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-180802

RESUMEN

A 25 year old patient with congenital hypoplastic anemia (Black-fan-Diamond syndrome) is described. This patient was hepatitis-antigen negative, had not received androgens and had a hepatoma develop in a transfusional hemochromatotic liver. Since androgens have been associated with hepatocellular carcinoma, the use of androgenic steroids for other than life-threatening symptoms in this disease should be avoided.


PIP: In this case report, the patient had been delivered by Caesarean section and weighed only 4 pounds at birth. The mother was O negative, the father A positive, and the infant A positive. Initial red cell count was 2.85 million/cu mm; white cell count, 19,200/cu mm; and hemoglobin 70% of normal. At 3 months of age hemoglobin was 10% of normal. Bone marrow examination revealed marked erythroid hyperplasia. A diagnosis of Blackfan-Diamond syndrome was made. He received blood transfusions every 2 or 3 weeks for the first 4 years of his life. During his lifetime he received 433 units of packed cells for the treatment of congenital hypoplastic anemia. Vitamin-B12, folic acid, and iron were given without benefit. At 8 years of age a spelectomy was done. 20 months after surgery he recovered from pneumonococcal meningitis without sequelae. Progressive signs of hemochromatosis developed and finally progressive signs of heart failure with edema. At 24 years of age severe epigastric pain developed. An open liver biopsy disclosed multiple liver nodules which proved to be hepatoma. Severe ascites followed the surgery. Pulmonary metastases of the liver tumor developed and heart failure. He died at age 25. This patient had received no androgen. He was consistently hepatitis antigen negative. He was prepubertal at the age of 25 and had almost no endogenous androgens. Alpha-fetoglobin was present. This test may be useful as a screening test for hepatoma.


Asunto(s)
Anemia Aplásica/congénito , Carcinoma Hepatocelular/etiología , Eritrocitos Anormales , Hemocromatosis/complicaciones , Neoplasias Hepáticas/etiología , Adulto , Andrógenos/efectos adversos , Andrógenos/uso terapéutico , Anemia Aplásica/complicaciones , Anemia Aplásica/tratamiento farmacológico , Transfusión Sanguínea , Antígenos de la Hepatitis B , Humanos , Masculino , Síndrome
15.
Transfusion ; 16(2): 135-40, 1976.
Artículo en Inglés | MEDLINE | ID: mdl-1258114

RESUMEN

A girl with Thalassemia major reacted to a transfusion of packed red blood cells with increasing respiratory distress until death 12 1/2 hours later. Chills and fever were followed by dry cough, dyspnea, and pulmonary edema. The recipient had lymphocytotoxic antibodies specific for donor leukocyte antigens HL-A11 and possibly W14. At autopsy, the lungs showed pulmonary edema with extensive nonspecific acute alveolar injury. Similar cases in the literature are reviewed.


Asunto(s)
Incompatibilidad de Grupos Sanguíneos/complicaciones , Transfusión Sanguínea , Antígenos de Histocompatibilidad , Hipersensibilidad Respiratoria/etiología , Adolescente , Femenino , Humanos , Edema Pulmonar/etiología , Edema Pulmonar/patología , Talasemia/terapia
16.
Proc Natl Acad Sci U S A ; 72(4): 1550-4, 1975 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1055426

RESUMEN

Purified alpha and beta globin complementary DNAs (cDNAs) have been separated from total radioactively labeled human globin cDNA using mRNA purified from liver of a hydrops fetalis (alpha thalassemia). The beta cDNA hybridizes to the hydrops fetalis mRNA while the alpha cDNA remains single-stranded. the purified alpha and beta cDNAs were assayed for their purity by their hybridization to mRNA prepared from reticulocytes of nonthalassemia, alpha thalassemia, and beta thalassemia subjects. The results indicate that the separated cDNAs are selective in hybridization to alpha or beta globin mRNAs, respectively. The previously reported deficiency of globin mRNA in thalassemia cells has been confirmed with these purified cDNAs. The purified alpha and beta cDNAs were hybridized to cellular DNA to non-thalassemia, beta+ thalassemia, and hydrops fetalis (alpha thalassemia) DNA. The alpha cDNA hybridized to hydrops fetalis liver DNA to a much lower extent that beta cDNA, confirming the previously reported deletion of alpha globin genes in hydrops fetalis. By contrast, both the alpha and beta DNA probes hybridized to the same extent to spleen DNA from non-thalassemia and from beta+ thalassemia patients. Between two and five globin genes in non-thalassemia and beta+ thalassemia DNA hybridize to beta cDNA and one to five to alpha cDNA. These studies indicate that in beta+ thalassemia, there is no detectable deletion in beta globin genes. The genetic defect in beta+ thalassemia appears to be due to either repression of transcription of beta globin genes or abnormal processing of beta globin mRNA.


Asunto(s)
ADN/análisis , Genes , Globinas/biosíntesis , Biosíntesis de Proteínas , Transcripción Genética , Médula Ósea/metabolismo , Células de la Médula Ósea , ADN/metabolismo , ADN Circular/análisis , ADN Circular/metabolismo , Edema/metabolismo , Femenino , Enfermedades Fetales/metabolismo , Heterocigoto , Humanos , Recién Nacido , Hígado/metabolismo , Hibridación de Ácido Nucleico , Embarazo , ARN Mensajero/metabolismo , Reticulocitos/metabolismo , Talasemia/metabolismo
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