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1.
Am Surg ; 89(8): 3671-3672, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37139898

RESUMEN

Intestinal non-rotation is an exceedingly rare clinical entity, especially as the etiology for small bowel obstruction following open-heart surgery in an elderly patient. Perisplenitis (also known as "sugar spleen") is also rarely identified during exploratory laparotomy, and is more often encountered post-mortem due to its benign disease course. These two entities were encountered in the same acutely decompensating patient, and while unrelated, serve as a reminder of the importance of recognizing variations in anatomy and understanding subsequent clinical significance.


Asunto(s)
Obstrucción Intestinal , Enfermedades del Bazo , Masculino , Humanos , Anciano , Azúcares , Intestinos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Intestino Delgado/cirugía , Enfermedades del Bazo/complicaciones , Enfermedades del Bazo/cirugía
2.
Clin Radiol ; 77(11): 855-863, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36055826

RESUMEN

AIM: To evaluate the usefulness of synthetic magnetic resonance imaging (MRI) performed before the initiation of neoadjuvant chemotherapy (NAC) in predicting whether breast cancers can achieve a pathological complete response (pCR) after the completion of NAC. MATERIALS AND METHODS: This retrospective study investigated 37 consecutive patients with 39 breast cancers (pCR: 14, and non-pCR: 25) who underwent dynamic contrast-enhanced (DCE)-MRI and synthetic MRI before the initiation of NAC. Using synthetic MRI images, quantitative values (T1 and T2 relaxation times, proton density [PD] and their standard deviations [SD]) were obtained in breast lesions, before (Pre-T1, Pre-T2, Pre-PD, SD of Pre-T1, SD of Pre-T2, SD of Pre-PD) and after (Gd-T1, Gd-T2, Gd-PD, SD of Gd-T1, SD of Gd-T2, SD of Gd-PD) contrast agent injection. The aforementioned quantitative values and several morphological features that were identified on DCE-MRI were compared between pCR and non-pCR. RESULTS: Multivariate analyses revealed that the SD of Pre-T2 (p=0.038) was significant and was an independent predictor of pCR, with an area under the receiver operating characteristics curve of 0.829. The sensitivity, specificity, and accuracy of the SD of Pre-T2 with an optimal cut-off value of 11.5 were 71.4%, 80%, and 76.3%, respectively. CONCLUSIONS: The SD of Pre-T2 obtained from synthetic MRI was used successfully to predict those breast cancers that would achieve a pCR after the completion of NAC; however, these results are preliminary and need to be verified by further studies.


Asunto(s)
Neoplasias de la Mama , Terapia Neoadyuvante , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Medios de Contraste/uso terapéutico , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Terapia Neoadyuvante/métodos , Protones , Estudios Retrospectivos , Resultado del Tratamiento
4.
J Eur Acad Dermatol Venereol ; 36(2): 247-254, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34704317

RESUMEN

BACKGROUND: Atopic dermatitis (AD) is an itchy, chronic and inflammatory skin condition, with dysfunctional immune response and skin barrier defects. Reduction of filaggrin (FLG) and tight junctions (TJ) proteins, such as claudin-1 (CLDN-1), expression in cutaneous epithelial barrier is remarkable in AD pathogenesis. Ocular involvement occurs in approximately 40% of AD patients leading to changes in the structure of the conjunctiva. OBJECTIVES: We aimed to evaluate the expression of FLG and CLDN-1 in the ocular surface of adults with AD, analysing bulbar conjunctival cells collected by a novel non-invasive cellular imprint. METHODS: Bulbar conjunctival epithelial cells were collected by cellular imprint technique, and FLG and CLDN-1 expression were assessed by immunofluorescence (IF) and real-time polymerase chain reaction (RT-PCR). RESULTS: We detected increased expression of FLG and CLDN-1, as well as their transcript levels in AD patients compared with healthy controls (HC). There was a positive correlation between tear film break-up time (TBUT) and FLG expression. Fluorescein staining was inversely associated with FLG expression. CONCLUSIONS: Our results may reflect a reactive response of the ocular surface to AD-related ocular inflammation and associated dry eye disease. Further investigations focusing on the role of FLG and TJ expression in the ocular surface of AD patients may increment the understanding of the pathophysiology of extracutaneous AD and developing future targeted therapies.


Asunto(s)
Dermatitis Atópica , Proteínas Filagrina , Claudina-1/genética , Dermatitis Atópica/genética , Humanos , Proteínas de Filamentos Intermediarios/genética , Proteínas de Filamentos Intermediarios/metabolismo , Mutación , Piel/metabolismo
5.
BMC Geriatr ; 21(1): 540, 2021 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-34635089

RESUMEN

BACKGROUND: While dementia is a common problem in Japan and the US, primary care physicians' practices and perspectives about diagnosing dementia in these different healthcare systems are unknown. METHODS: Qualitative research was conducted in an ethnographic tradition using semi-structured interviews and thematic analysis in primary care settings across Japan and in the Midwest State of Michigan, US. Participants were a total of 48 primary care physicians, 24 each from Japan and the US participated. Both groups contained a mixture of geographic areas (rural/urban), gender, age, and years of experience as primary care physicians. RESULTS: Participants in Japan and the US voiced similar practices for making the diagnosis of dementia and held similar views about the desired benefits of diagnosing dementia. Differences were found in attitudes about the appropriate timing of formally diagnosing dementia. Japanese physicians tended to make a formal diagnosis when problems that would benefit from long-term care services emerged for family members. US physicians were more proactive in diagnosing dementia in the early stages by screening for dementia in health check-ups and promoting advance directives when the patients were still capable of decision-making. Views about appropriate timing of diagnostic testing for dementia in the two systems reflect what medical or nursing care services physicians can use to support dementia patients and caregivers. CONCLUSIONS: Benefits of making the diagnosis included the need to activate the long-term care services in Japan and for early intervention and authoring advance directives in the US. Testing to establish an early diagnosis of dementia by primary care physicians only partly relates to testing and treatment options available. Benefits of making the diagnosis included the need to activate the long-term care services in Japan and for early intervention and authoring advance directives in the US.


Asunto(s)
Demencia , Médicos de Atención Primaria , Cuidadores , Demencia/diagnóstico , Demencia/epidemiología , Humanos , Japón/epidemiología , Investigación Cualitativa , Estados Unidos/epidemiología
6.
Phys Rev Lett ; 127(7): 077201, 2021 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-34459637

RESUMEN

We report ^{51}V NMR and inelastic neutron scattering (INS) measurements on a quasi-1D antiferromagnet BaCo_{2}V_{2}O_{8} under transverse field along the [010] direction. The scaling behavior of the spin-lattice relaxation rate above the Néel temperatures unveils a 1D quantum critical point (QCP) at H_{c}^{1D}≈4.7 T, which is masked by the 3D magnetic order. With the aid of accurate analytical analysis and numerical calculations, we show that the zone center INS spectrum at H_{c}^{1D} is precisely described by the pattern of the 1D quantum Ising model in a magnetic field, a class of universality described in terms of the exceptional E_{8} Lie algebra. These excitations are nondiffusive over a certain field range when the system is away from the 1D QCP. Our results provide an unambiguous experimental realization of the massive E_{8} phase in the compound, and open a new experimental route for exploring the dynamics of quantum integrable systems as well as physics beyond integrability.

9.
Rhinology ; 58(3): 241-247, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32091032

RESUMEN

BACKGROUND: Intralymphatic immunotherapy (ILIT) for allergic patients requires only a few intralymphatic injections of the allergen. However, the effectiveness and safety for Japanese cedar pollinosis are unclear. The objectives of this study were to clarify whether and how long ILIT is effective for pollinosis, and its safety. METHODS: In an open pilot investigation followed by a double-blind, placebo-controlled study, patients with Japanese cedar pollinosis received 3 intralymphatic inguinal injections of the pollen extracts before the first pollen season. The symptom medication score (SMS), nasal provocation testing and scoring visual analogue scale (VAS) were assessed after the first-third seasons. RESULTS: (1) Although mild adverse events were induced at the injected site, severe adverse events were not noted. (2) During the latter part of the first season, ILIT-treated patients (n=12) tended to show improved SMS compared to placebo-treated (n=6) without statistical significance. When assessed by nasal provocation testing and VAS scoring after the first season, the effectiveness of ILIT was significant. (3) The effects of ILIT continued until the second or third season. (4) Neither allergen-specific antibodies nor Treg/Breg cells changed in the peripheral blood. CONCLUSIONS: ILIT was safe and effective for Japanese cedar pollinosis. The clinical effects remained for 1-2 years.


Asunto(s)
Cryptomeria , Desensibilización Inmunológica , Rinitis Alérgica Estacional , Alérgenos , Cryptomeria/inmunología , Método Doble Ciego , Humanos , Polen/inmunología , Rinitis Alérgica Estacional/terapia
10.
Clin Radiol ; 75(5): 398.e1-398.e8, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32019671

RESUMEN

AIM: To evaluate the utility of synthetic magnetic resonance imaging (MRI) of the breast in predicting the Ki-67 status in patients with oestrogen receptor (ER)-positive breast cancer. MATERIALS AND METHODS: Forty-nine patients with 50 histopathologically proven breast cancers who underwent additional synthetic MRI were enrolled in the present study. Using synthetic MRI images, T1 and T2 relaxation times and their standard deviations (SD) in the breast lesions before (T1-Pre, T2-Pre, PD-Pre, SD of T1-Pre, SD of T2-Pre, SD of PD-Pre) and after (T1-Gd, T2-Gd, PD-Gd, SD of T1-Gd, SD of T2-Gd, SD of PD-Gd) contrast agent injection were obtained. These quantitative values were compared between the low Ki-67 expression (<14%) lesions (low-proliferation group: n=23) and high Ki-67 expression (≥14%) lesions (high-proliferation group: n=27). RESULTS: The univariate analysis showed that the SD of T1-Gd (p<0.001) and T2-Gd (p=0.042) were significantly higher in the high-proliferation group than in the low-proliferation group. Multivariate analysis further showed that the SD of T1-Gd was a significant and independent predictor of Ki-67 expression, with an area under the receiver operating characteristic (AUROC) curve of 0.885. The sensitivity, specificity, and accuracy of the SD of T1-Gd with an optimal cut-off value of 98.5 were 77.8%, 87%, and 82%, respectively. CONCLUSION: The SD of T1-Gd obtained from synthetic MRI was useful to predict Ki-67 status.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/metabolismo , Antígeno Ki-67/metabolismo , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/cirugía , Medios de Contraste , Estudios de Factibilidad , Femenino , Humanos , Aumento de la Imagen/métodos , Biopsia Guiada por Imagen , Persona de Mediana Edad , Receptores de Estrógenos/metabolismo , Estudios Retrospectivos , Sensibilidad y Especificidad
11.
Neuropathol Appl Neurobiol ; 46(2): 111-124, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31179566

RESUMEN

AIMS: Alterations in microenvironments are a hallmark of cancer, and these alterations in germinomas are of particular significance. Germinoma, the most common subtype of central nervous system germ cell tumours, often exhibits massive immune cell infiltration intermingled with tumour cells. The role of these immune cells in germinoma, however, remains unknown. METHODS: We investigated the cellular constituents of immune microenvironments and their clinical impacts on prognosis in 100 germinoma cases. RESULTS: Patients with germinomas lower in tumour cell content (i.e. higher immune cell infiltration) had a significantly longer progression-free survival time than those with higher tumour cell contents (P = 0.03). Transcriptome analyses and RNA in-situ hybridization indicated that infiltrating immune cells comprised a wide variety of cell types, including lymphocytes and myelocyte-lineage cells. High expression of CD4 was significantly associated with good prognosis, whereas elevated nitric oxide synthase 2 was associated with poor prognosis. PD1 (PDCD1) was expressed by immune cells present in most germinomas (93.8%), and PD-L1 (CD274) expression was found in tumour cells in the majority of germinomas examined (73.5%). CONCLUSIONS: The collective data strongly suggest that infiltrating immune cells play an important role in predicting treatment response. Further investigation should lead to additional categorization of germinoma to safely reduce treatment intensity depending on tumour/immune cell balance and to develop possible future immunotherapies.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/inmunología , Linaje de la Célula/inmunología , Germinoma/diagnóstico , Germinoma/inmunología , Neoplasias Encefálicas/metabolismo , Perfilación de la Expresión Génica , Germinoma/metabolismo , Humanos , Pronóstico , Transcriptoma , Microambiente Tumoral/inmunología
12.
Clin Radiol ; 74(12): 975.e1-975.e9, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31540704

RESUMEN

AIM: To evaluate the value of magnetic resonance imaging (MRI) features, including liver stiffness measured by magnetic resonance elastography (MRE) and the presence of hepatobiliary phase (HBP) hypointense nodule without arterial phase hyperenhancement (APHE), for predicting late recurrence (>1 year) after surgery for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This retrospective study included 124 consecutive patients who had undergone surgery for HCC and preoperative MRI. After excluding patients with early recurrence within 1 year after surgery, 89 patients were analysed. Preoperative MRI images were reviewed by a radiologist to record imaging findings, including (1) liver stiffness by MRE, (2) size of the HCCs, (3) number of HCCs, and (4) presence of HBP hypointense nodule without APHE. Pathological findings included tumour grade, vascular/biliary/capsule invasion, and fibrosis stage of the liver. Considering imaging/pathological findings and patients' characteristics as dependent variables, Cox proportional hazards model analysis was performed to identify independent factors associated with late recurrence after surgery. RESULTS: The median follow-up period was 37.3 months. During follow-up, 29 patients (32.5%) developed late recurrence after surgery. In multivariate analysis, underlying liver disease (viral hepatitis) and presence of HBP hypointense nodules without APHE (p=0.010 and 0.033, respectively) were independently associated with disease-free survival (DFS). Kaplan-Meier analysis revealed that patients with HBP hypointense nodules without APHE had a significantly lower DFS rate than those without the nodule (39.2% versus 74.1% at 3 years after surgery, p=0.008). CONCLUSION: The presence of HBP hypointense nodules without APHE was an indicator of late recurrence after surgery for HCC.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/cirugía , Disostosis Craneofacial , Supervivencia sin Enfermedad , Femenino , Humanos , Deformidades Congénitas de las Extremidades , Hígado/diagnóstico por imagen , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/cirugía , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
13.
J Phys Condens Matter ; 31(50): 505704, 2019 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-31484172

RESUMEN

The magnetoelectric effect in the RX3(BO3)4 system (R = Ho, Eu, Sm, Nd, Gd; X = Fe, Al) varies significantly with the cation R despite very similar structural arrangements. Our structural studies reveal a symmetry reducing tilting of the BO3 planes and of the FeO6 polyhedra in the systems exhibiting low magnetic field induced electric polarization. Neutron scattering measurements reveal a lack of magnetic ordering indicating the primary importance of the atomic structure in the multiferroic behavior of this system.

14.
Phys Rev Lett ; 123(4): 047201, 2019 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-31491259

RESUMEN

The n-type HgCr_{2}Se_{4} exhibits a sharp semiconductor-to-metal transition (SMT) in resistivity accompanying the ferromagnetic order at T_{C}=106 K. Here, we investigate the effects of pressure and magnetic field on the concomitant SMT and ferromagnetic order by measuring resistivity, dc and ac magnetic susceptibility, as well as single-crystal neutron diffraction under various pressures up to 8 GPa and magnetic fields up to 8 T. Our results demonstrate that the ferromagnetic metallic ground state of n-type HgCr_{2}Se_{4} is destabilized and gradually replaced by an antiferromagnetic, most likely a spiral magnetic, and insulating ground state upon the application of high pressure. On the other hand, the application of external magnetic fields can restore the ferromagnetic metallic state again at high pressures, resulting in a colossal magnetoresistance (CMR) as high as ∼ 3×10^{11}% under 5 T and 2 K at 4 GPa. The present study demonstrates that n-type HgCr_{2}Se_{4} is located at a peculiar critical point where the balance of competition between ferromagnetic and antiferromagnetic interactions can be easily tipped by external stimuli, providing a new platform for achieving CMR in a single-valent system.

15.
Phys Rev Lett ; 122(21): 217003, 2019 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-31283313

RESUMEN

We report neutron scattering measurements of single-crystalline YFe_{2}Ge_{2} in the normal state, which has the same crystal structure as the 122 family of iron pnictide superconductors. YFe_{2}Ge_{2} does not exhibit long-range magnetic order but exhibits strong spin fluctuations. Like the iron pnictides, YFe_{2}Ge_{2} displays anisotropic stripe-type antiferromagnetic spin fluctuations at (π, 0, π). More interesting, however, is the observation of strong spin fluctuations at the in-plane ferromagnetic wave vector (0, 0, π). These ferromagnetic spin fluctuations are isotropic in the (H, K) plane, whose intensity exceeds that of stripe spin fluctuations. Both the ferromagnetic and stripe spin fluctuations remain gapless down to the lowest measured energies. Our results naturally explain the absence of magnetic order in YFe_{2}Ge_{2} and also imply that the ferromagnetic correlations may be a key ingredient for iron-based materials.

17.
J Phys Condens Matter ; 31(38): 384001, 2019 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-31158819

RESUMEN

High-pressure neutron diffraction (HPND) experiments in extended pressure and temperature ranges can provide invaluable information for understanding many pressure-induced emergent phenomena, such as unusual phase transitions and quantum critical behavior involving spin, orbital, charge and structural degrees of freedom, in strongly correlated materials. Many apparatuses for different purposes of HPND experiments have been developed in several laboratories. Recently, a clamp-type cubic anvil high pressure cell that can generate pressure over 7 GPa at 3 K was developed for low-temperature HPND measurements. In this paper, characteristics of the clamp-type cubic anvil high pressure cell are presented and its performances are demonstrated by measuring magnetic neutron scattering under pressure on MnP single crystal samples.

18.
Nat Commun ; 10(1): 1247, 2019 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-30886147

RESUMEN

Mutual control of the electricity and magnetism in terms of magnetic (H) and electric (E) fields, the magnetoelectric (ME) effect, offers versatile low power consumption alternatives to current data storage, logic gate, and spintronic devices. Despite its importance, E-field control over magnetization (M) with significant magnitude was observed only at low temperatures. Here we have successfully stabilized a simultaneously ferrimagnetic and ferroelectric phase in a Y-type hexaferrite single crystal up to 450 K, and demonstrated the reversal of large non-volatile M by E field close to room temperature. Manipulation of the magnetic domains by E field is directly visualized at room temperature by using magnetic force microscopy. The present achievement provides an important step towards the application of ME multiferroics.

19.
Int J Obstet Anesth ; 37: 36-44, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30482720

RESUMEN

BACKGROUND: Hypotension induced by spinal anesthesia for cesarean section causes a decrease in maternal regional cerebral blood volume and oxygenation. We used near-infrared spectroscopy to determine whether prophylactic infusion of phenylephrine attenuates these decreases. METHODS: Sixty patients undergoing bupivacaine spinal anesthesia for cesarean section were randomly divided into one of three intravenous infusion groups: saline (P0), phenylephrine 25 (P25) or 50 µg/min (P50). Mean arterial pressure, heart rate and near-infrared spectroscopy measurements were made at one-minute intervals for 20 minutes, and oxyhemoglobin, deoxy-hemoglobin and total-hemoglobin concentrations and tissue oxygenation index were determined. Mean changes in the values between baseline and each measurement time after intrathecal injection were compared. RESULTS: Significant decreases in mean arterial pressure were seen in group P0 compared to P25 and P50 (P <0.01). Heart rate decreased in a dose-dependent manner during phenylephrine infusion (P0 vs. P25 and P50, P25 vs. P50; P <0.05). Significantly higher total-hemoglobin levels were observed in the phenylephrine groups versus the P0 group (P <0.01). The largest decrease in tissue oxygenation index was found in the P50, followed by P0 and P25 groups (P0 vs. P25 and P50, P25 vs. P50; P <0.05). CONCLUSION: Prophylactic infusion of phenylephrine, especially at 25 µg/min, can effectively suppress decreases in regional cerebral blood volume and regional cerebral blood oxygenation after induction of spinal anesthesia for cesarean section.


Asunto(s)
Anestesia Obstétrica/efectos adversos , Anestesia Raquidea/efectos adversos , Encéfalo/metabolismo , Volumen Sanguíneo Cerebral/efectos de los fármacos , Cesárea , Oxígeno/metabolismo , Fenilefrina/uso terapéutico , Adulto , Presión Arterial , Método Doble Ciego , Femenino , Humanos , Embarazo
20.
Phys Rev B ; 100(13)2019.
Artículo en Inglés | MEDLINE | ID: mdl-33644522

RESUMEN

An inelastic neutron scattering study has been performed in an S = 3/2 bilayer honeycomb lattice compound Bi3Mn4O12(NO3) at ambient and high magnetic fields. Relatively broad and monotonically dispersive magnetic excitations were observed at ambient field, where no long-range magnetic order exists. In the magnetic-field-induced long-range ordered state at 10 T, the magnetic dispersions become slightly more intense, albeit still broad as in the disordered state, and two excitation gaps, probably originating from an easy-plane magnetic anisotropy and intrabilayer interactions, develop. Analyzing the magnetic dispersions using the linear spin-wave theory, we estimated the intraplane and intrabilayer magnetic interactions, which are almost consistent with those determined by ab initio density functional theory calculations [M. Alaei et al., Phys. Rev. B 96, 140404(R) (2017)], except the third and fourth neighbor intrabilayer interactions. Most importantly, as predicted by the theory, there is no significant frustration in the honeycomb plane but frustrating intrabilayer interactions probably give rise to the disordered ground state.

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