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1.
Phys Rev Lett ; 130(26): 261002, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37450817

RESUMEN

Multiple viable theoretical models predict heavy dark matter particles with a mass close to the Planck mass, a range relatively unexplored by current experimental measurements. We use 219.4 days of data collected with the XENON1T experiment to conduct a blind search for signals from multiply interacting massive particles (MIMPs). Their unique track signature allows a targeted analysis with only 0.05 expected background events from muons. Following unblinding, we observe no signal candidate events. This Letter places strong constraints on spin-independent interactions of dark matter particles with a mass between 1×10^{12} and 2×10^{17} GeV/c^{2}. In addition, we present the first exclusion limits on spin-dependent MIMP-neutron and MIMP-proton cross sections for dark matter particles with masses close to the Planck scale.

2.
Phys Rev Lett ; 131(4): 041003, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37566859

RESUMEN

We report on the first search for nuclear recoils from dark matter in the form of weakly interacting massive particles (WIMPs) with the XENONnT experiment, which is based on a two-phase time projection chamber with a sensitive liquid xenon mass of 5.9 ton. During the (1.09±0.03) ton yr exposure used for this search, the intrinsic ^{85}Kr and ^{222}Rn concentrations in the liquid target are reduced to unprecedentedly low levels, giving an electronic recoil background rate of (15.8±1.3) events/ton yr keV in the region of interest. A blind analysis of nuclear recoil events with energies between 3.3 and 60.5 keV finds no significant excess. This leads to a minimum upper limit on the spin-independent WIMP-nucleon cross section of 2.58×10^{-47} cm^{2} for a WIMP mass of 28 GeV/c^{2} at 90% confidence level. Limits for spin-dependent interactions are also provided. Both the limit and the sensitivity for the full range of WIMP masses analyzed here improve on previous results obtained with the XENON1T experiment for the same exposure.

3.
Phys Rev Lett ; 131(14): 142501, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37862664

RESUMEN

We present the measurement of the two-neutrino double-ß decay rate of ^{76}Ge performed with the GERDA Phase II experiment. With a subset of the entire GERDA exposure, 11.8 kg yr, the half-life of the process has been determined: T_{1/2}^{2ν}=(2.022±0.018_{stat}±0.038_{syst})×10^{21} yr. This is the most precise determination of the ^{76}Ge two-neutrino double-ß decay half-life and one of the most precise measurements of a double-ß decay process. The relevant nuclear matrix element can be extracted: M_{eff}^{2ν}=(0.101±0.001).

5.
Phys Rev Lett ; 129(16): 161805, 2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36306777

RESUMEN

We report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target reduced the background in the (1, 30) keV search region to (15.8±1.3) events/(ton×year×keV), the lowest ever achieved in a dark matter detector and ∼5 times lower than in XENON1T. With an exposure of 1.16 ton-years, we observe no excess above background and set stringent new limits on solar axions, an enhanced neutrino magnetic moment, and bosonic dark matter.

6.
Dig Dis Sci ; 67(7): 2805-2808, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35650417

RESUMEN

We report a case of a 73-year-old woman affected by Lemmel's syndrome, a rare type of obstructive jaundice caused by a periampullary duodenal diverticulum. The patient was admitted to the Emergency Department for pneumonia associated with mild epigastric pain and vomiting. While hospitalized for antibiotic treatment, the appearance of jaundice led us to discover a periampullary duodenal diverticulum by endoscopy and CT scan. The jaundice was successfully managed endoscopically with removal of food debris from the diverticulum.


Asunto(s)
Divertículo , Enfermedades Duodenales , Ictericia Obstructiva , Ictericia , Dolor Abdominal/etiología , Anciano , Divertículo/complicaciones , Divertículo/diagnóstico por imagen , Divertículo/cirugía , Enfermedades Duodenales/complicaciones , Enfermedades Duodenales/diagnóstico por imagen , Femenino , Humanos , Ictericia Obstructiva/etiología , Síndrome
7.
Dig Dis Sci ; 67(4): 1116-1127, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35318553

RESUMEN

Biliary lithiasis is common worldwide, affecting almost 20% of the general population, though few experience symptoms. The frequency of choledocholithiasis in patients with symptomatic cholelithiasis is estimated to be 10-33%, depending on patients' age. Unlike gallbladder lithiasis, the medical and surgical treatment of common bile duct stones is uncertain, having changed over the last few years. The prior gold standard treatment for cholelithiasis and choledocholithiasis was open cholecystectomy with bile duct clearance, choledochotomy, and/or surgical sphincterotomy. In the last 10-15 years, new treatment approaches to the complex pathology of choledocholithiasis have emerged with the advent of endoscopic retrograde cholangiopancreatography (ERCP), laparoscopic surgery, and advanced diagnostic procedures. Although ERCP followed by laparoscopic cholecystectomy is the preferred mode of management, a single-step strategy (laparo-endoscopic rendezvous) has gained acceptance due to lesser morbidity and a lower risk of iatrogenic damage. Given the above, a tailored approach relying on careful evaluation of the disease is necessary in order to minimize complication risks and overall costs. Yet, the debate remains open, with no consensus on the superiority of laparo-endoscopic rendezvous to more conventional approaches.


Asunto(s)
Colecistectomía Laparoscópica , Coledocolitiasis , Cálculos Biliares , Colangiopancreatografia Retrógrada Endoscópica , Colecistectomía Laparoscópica/efectos adversos , Colecistectomía Laparoscópica/métodos , Coledocolitiasis/diagnóstico por imagen , Coledocolitiasis/cirugía , Cálculos Biliares/complicaciones , Humanos
8.
Dig Dis Sci ; 67(5): 1733-1738, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35394594

RESUMEN

Duodenal follicular lymphoma (DFL) is a rare variety of non-Hodgkin's lymphoma of the gastrointestinal tract that usually carries a favorable course, recognized as a new entity in 2016. It is usually diagnosed at an early stage located predominantly in the second portion of the duodenum. We report the case of a 74-year-old male patient with epigastric pain in whom gastroscopy revealed white mucosal nodules that were pathologically diagnosed as grade 1-2 DFL. Staging investigations revealed secondary lesions in the spleen and at the base of the tongue together with latero-cervical adenopathy. The tumor was stage IV according to the Lugano staging system. We reviewed the recent (last five years) literature defining the importance of combination therapy in the advanced stage. The patient achieved complete remission of the disease through chemoimmunotherapy following the Rituximab-Bendamustine scheme.


Asunto(s)
Linfoma Folicular , Linfoma no Hodgkin , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Duodeno/patología , Humanos , Linfoma Folicular/diagnóstico , Linfoma Folicular/tratamiento farmacológico , Linfoma Folicular/patología , Masculino , Inducción de Remisión , Rituximab/uso terapéutico
9.
Dig Dis Sci ; 66(10): 3290-3295, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34189669

RESUMEN

We report the case of a 87-year-old woman admitted to our Emergency Department for mild abdominal pain associated with vomiting. An abdominal X-ray showed gas present in the portal venules of the left hepatic lobe, a finding associated with numerous surgical and medical conditions. The patient was successfully managed with conservative treatment. Isolated intrahepatic gas is a rare radiologic finding; emergency surgery should be performed only when there are signs of associated acute intestinal infarction.


Asunto(s)
Embolia Aérea/diagnóstico por imagen , Vena Porta/diagnóstico por imagen , Vena Porta/patología , Anciano de 80 o más Años , Embolia Aérea/terapia , Femenino , Humanos , Tomografía Computarizada por Rayos X
10.
Dig Dis Sci ; 66(5): 1436-1440, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33511490

RESUMEN

Adenocarcinoma as the primary cause of bowel intussusception is uncommon. We describe the case of a 86-year-old patient admitted for ileocecal intussusception due to the presence of adenocarcinoma, located in the ileocecal valve and right colon. The etiologies of intussusception, its diagnosis, and conservative or surgical treatments are discussed, with attention placed on the indications for reduction of the invagination prior to surgical resection.


Asunto(s)
Adenocarcinoma/complicaciones , Enfermedades del Íleon/etiología , Neoplasias del Íleon/complicaciones , Válvula Ileocecal , Intususcepción/etiología , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Anciano de 80 o más Años , Femenino , Humanos , Enfermedades del Íleon/diagnóstico por imagen , Enfermedades del Íleon/cirugía , Neoplasias del Íleon/diagnóstico por imagen , Neoplasias del Íleon/patología , Neoplasias del Íleon/cirugía , Válvula Ileocecal/diagnóstico por imagen , Válvula Ileocecal/patología , Válvula Ileocecal/cirugía , Intususcepción/diagnóstico por imagen , Intususcepción/cirugía , Estadificación de Neoplasias , Resultado del Tratamiento
11.
Dig Dis Sci ; 66(1): 41-44, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32990867

RESUMEN

Giant colonic diverticulum, defined as a single diverticulum ≤ 4 cm, is rarely encountered. Due to the high incidence of complications related to the disease, obtaining the correct diagnosis early in the disease course is essential. Diagnosis is usually reached by conventional and cross-sectional abdominal radiography. Treatment decisions should be ideally made by a multidisciplinary discussion among surgeons, interventional radiologists, and the patient. The treatment of choice is the surgical management by open or laparoscopic approach.


Asunto(s)
Divertículo del Colon/complicaciones , Divertículo del Colon/diagnóstico por imagen , Obstrucción del Cuello de la Vejiga Urinaria/diagnóstico por imagen , Obstrucción del Cuello de la Vejiga Urinaria/etiología , Anciano , Divertículo del Colon/cirugía , Femenino , Humanos , Vejiga Urinaria/diagnóstico por imagen , Vejiga Urinaria/cirugía , Obstrucción del Cuello de la Vejiga Urinaria/cirugía
12.
Phys Rev Lett ; 125(1): 011801, 2020 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-32678643

RESUMEN

We present the first search for bosonic superweakly interacting massive particles (super-WIMPs) as keV-scale dark matter candidates performed with the GERDA experiment. GERDA is a neutrinoless double-ß decay experiment which operates high-purity germanium detectors enriched in ^{76}Ge in an ultralow background environment at the Laboratori Nazionali del Gran Sasso (LNGS) of INFN in Italy. Searches were performed for pseudoscalar and vector particles in the mass region from 60 keV/c^{2} to 1 MeV/c^{2}. No evidence for a dark matter signal was observed, and the most stringent constraints on the couplings of super-WIMPs with masses above 120 keV/c^{2} have been set. As an example, at a mass of 150 keV/c^{2} the most stringent direct limits on the dimensionless couplings of axionlike particles and dark photons to electrons of g_{ae}<3×10^{-12} and α^{'}/α<6.5×10^{-24} at 90% credible interval, respectively, were obtained.

13.
Phys Rev Lett ; 125(25): 252502, 2020 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-33416389

RESUMEN

The GERmanium Detector Array (GERDA) experiment searched for the lepton-number-violating neutrinoless double-ß (0νßß) decay of ^{76}Ge, whose discovery would have far-reaching implications in cosmology and particle physics. By operating bare germanium diodes, enriched in ^{76}Ge, in an active liquid argon shield, GERDA achieved an unprecedently low background index of 5.2×10^{-4} counts/(keV kg yr) in the signal region and met the design goal to collect an exposure of 100 kg yr in a background-free regime. When combined with the result of Phase I, no signal is observed after 127.2 kg yr of total exposure. A limit on the half-life of 0νßß decay in ^{76}Ge is set at T_{1/2}>1.8×10^{26} yr at 90% C.L., which coincides with the sensitivity assuming no signal.

14.
Dig Dis Sci ; 65(5): 1315-1320, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32036512

RESUMEN

INTRODUCTION: Pelvic schwannomas are rare, mostly benign tumors. They are usually asymptomatic until their massive growth compresses adjacent organs. We describe the case of a 53-year-old man with a pelvic schwannoma who initially complained of constipation and urinary retention. AREAS COVERED: We analyzed the clinical presentation, histopathology, diagnostic imaging tools, and the treatment options for pelvic schwannomas, compared with the few other cases reported in the literature. EXPERT COMMENTARY: Pelvic schwannomas are masses that can grow to considerable size, producing symptoms over time. Due to their size and localization, surgery, although difficult, is the only available treatment.


Asunto(s)
Neurilemoma/patología , Neoplasias Pélvicas/patología , Humanos , Masculino , Persona de Mediana Edad
15.
Dig Dis Sci ; 65(1): 66-70, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31732908

RESUMEN

Pancreatic pseudocysts commonly complicate acute pancreatitis. They can evolve either asymptomatically or with important symptoms. Treatment can be surgical, endoscopic, or percutaneous. The authors present a case report of a 78-year-old man who developed symptoms of an acute abdomen during hospitalization. A CT scan showed two pancreatic pseudocysts (diameters 10 cm and 7.5 cm) that were successfully drained endoscopically. Multiple pancreatic pseudocysts can be treated successfully via an endoscopic approach.


Asunto(s)
Drenaje/métodos , Endoscopía del Sistema Digestivo , Seudoquiste Pancreático/terapia , Anciano , Antibacterianos/uso terapéutico , Drenaje/instrumentación , Endoscopía del Sistema Digestivo/instrumentación , Enterobacter/aislamiento & purificación , Humanos , Masculino , Seudoquiste Pancreático/diagnóstico por imagen , Seudoquiste Pancreático/microbiología , Pseudomonas aeruginosa/aislamiento & purificación , Stents , Resultado del Tratamiento
16.
Dig Dis Sci ; 65(6): 1643-1651, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32300935

RESUMEN

Dedifferentiated liposarcomas are rare; localization of these tumors in the descending colon is extremely uncommon. We describe the case of a 75-year-old man with a dedifferentiated liposarcoma originating from the descending colon that manifested as partial bowel obstruction. The very uncommon presentation of this rare disease contributed to a challenging diagnostic process. The patient was successfully treated by surgical resection of the mass through left hemicolectomy. Although exceptionally unusual, soft tissue sarcomas should be considered in the differential diagnosis for bowel obstruction. Currently, radical resection of the mass is considered to be the first-line treatment.


Asunto(s)
Neoplasias del Colon/diagnóstico , Liposarcoma/diagnóstico , Anciano , Neoplasias del Colon/patología , Neoplasias del Colon/cirugía , Humanos , Liposarcoma/patología , Liposarcoma/cirugía , Masculino
17.
Dig Dis Sci ; 65(10): 2800-2804, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32572657

RESUMEN

INTRODUCTION: Isolated heterotopic pancreas (HP) as the primary cause of bowel intussusception is extremely rare. We report a case of a 33-year-old female patient with spina bifida admitted to the Emergency Surgical Department for ileal intussusception due to the presence of heterotopic pancreas associated with endometriosis. AREAS COVERED: Symptomatic ileal intussusception for ectopic pancreas is usually associated with overt gastrointestinal blood loss (predominantly melena), abdominal pain, vomiting, and weight loss. Treatment is universally surgical. EXPERT COMMENTARY: Isolated heterotopic pancreas is a rare condition; it should be considered in the differential diagnosis of bowel intussusception.


Asunto(s)
Coristoma/complicaciones , Endometriosis/complicaciones , Enfermedades del Íleon/complicaciones , Intususcepción/etiología , Páncreas , Disrafia Espinal/complicaciones , Adulto , Coristoma/diagnóstico por imagen , Coristoma/cirugía , Endometriosis/diagnóstico por imagen , Endometriosis/cirugía , Femenino , Humanos , Enfermedades del Íleon/diagnóstico por imagen , Enfermedades del Íleon/cirugía , Intususcepción/diagnóstico por imagen , Intususcepción/cirugía , Disrafia Espinal/diagnóstico , Resultado del Tratamiento
18.
Dig Dis Sci ; 65(2): 391-398, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31728786

RESUMEN

INTRODUCTION: Amyloidosis is an uncommon disease caused by the deposition of amyloid fibrils in tissues. This disease does not usually require surgical intervention, which could be warranted in the presence of complications such as bleeding, obstruction, or perforation. We present a case of primary amyloidosis of the colon in a patient affected by polymyositis who underwent Hartmann's procedure after a spontaneous colonic perforation. After 2 months of well-being, the patient underwent two consecutive surgical procedures for stenosis of the ostomy orifice. AREAS COVERED: A review of the literature has been performed, gathering case reports highlighting the distribution of this disease by age, gender, location, and treatment when available. EXPERT COMMENTARY: Gastrointestinal amyloid disease is a rare condition, and it could be considered among the rare causes of intestinal perforation. Timely surgical management is often necessary.


Asunto(s)
Amiloidosis/patología , Colectomía , Colitis/patología , Colostomía , Perforación Intestinal/cirugía , Anciano , Amiloidosis/complicaciones , Amiloidosis/diagnóstico , Colitis/diagnóstico , Colitis/etiología , Enfermedades del Colon/complicaciones , Enfermedades del Colon/diagnóstico , Enfermedades del Colon/patología , Constricción Patológica , Femenino , Humanos , Perforación Intestinal/diagnóstico , Perforación Intestinal/etiología , Complicaciones Posoperatorias/cirugía , Reoperación , Estomas Quirúrgicos/patología
19.
Dig Dis Sci ; 64(12): 3431-3435, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31620928

RESUMEN

INTRODUCTION: Myelolipomas are rare, benign neoplasms usually arising from the retroperitoneum. They represent an unusual diagnostic challenge due to their vague GI symptoms. We present a case of an 81-year-old patient complaining of severe dyspepsia. An abdominal CT scan and a fine needle biopsy lead to a diagnosis of giant retroperitoneal myelolipoma. A complete surgical resection was performed; no evidence of recurrent tumor was noted after 10 months. AREAS COVERED: Giant myelolipomas are very rare lesions. Clinical diagnosis of myelolipomas can be problematic due to their indefinite symptoms. CT scan and fine needle biopsy can be useful to reach a diagnosis, although they cannot be used to exclude malignancy in giant lesions. Surgery is the principal treatment if the tumor is symptomatic or > 7 cm. Follow-up is not mandatory due to the lack of any example of recurrence described in literature. EXPERT COMMENTARY: Despite the size of the neoplasms, since most of the complaints are vague, patients with this diagnosis should be considered among patients with unexplained gastrointestinal symptoms. Since malignancy cannot be excluded based on preoperative and intraoperative biopsy, an aggressive surgical approach is essential.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/diagnóstico por imagen , Mielolipoma/diagnóstico por imagen , Neoplasias Retroperitoneales/diagnóstico por imagen , Neoplasias de las Glándulas Suprarrenales/patología , Neoplasias de las Glándulas Suprarrenales/cirugía , Anciano de 80 o más Años , Dispepsia , Humanos , Masculino , Mielolipoma/patología , Mielolipoma/cirugía , Neoplasias Retroperitoneales/patología , Neoplasias Retroperitoneales/cirugía , Carga Tumoral , Ultrasonografía
20.
Dig Dis Sci ; 64(11): 3086-3091, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31559552

RESUMEN

Although the diagnosis of visceral pseudoaneurysm is unusual, it requires emergent attention due to the risk of rupture. We describe a 70-year-old man with a gastroduodenal artery pseudoaneurysm that manifested as recurrent hemorrhage. We highlight the possible etiologies, clinical presentations, diagnostic tools, and treatment options for this condition. In this instance, the patient was successfully treated by selective angioembolization. A visceral pseudoaneurysm should be considered in patients with abdominal pain and GI hemorrhage. At present, angioembolization is a first-line therapy.


Asunto(s)
Aneurisma Falso/diagnóstico por imagen , Aneurisma Falso/cirugía , Artería Gástrica/diagnóstico por imagen , Artería Gástrica/cirugía , Hemorragia Gastrointestinal/diagnóstico por imagen , Hemorragia Gastrointestinal/cirugía , Anciano , Duodeno/irrigación sanguínea , Duodeno/diagnóstico por imagen , Duodeno/cirugía , Endoscopía Gastrointestinal/métodos , Humanos , Masculino , Recurrencia
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