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1.
Nat Commun ; 13(1): 4329, 2022 07 28.
Article in English | MEDLINE | ID: mdl-35902573

ABSTRACT

Nanofibrils play a pivotal role in spider silk and are responsible for many of the impressive properties of this unique natural material. However, little is known about the internal structure of these protein fibrils. We carry out polarized Raman and polarized Fourier-transform infrared spectroscopies on native spider silk nanofibrils and determine the concentrations of six distinct protein secondary structures, including ß-sheets, and two types of helical structures, for which we also determine orientation distributions. Our advancements in peak assignments are in full agreement with the published silk vibrational spectroscopy literature. We further corroborate our findings with X-ray diffraction and magic-angle spinning nuclear magnetic resonance experiments. Based on the latter and on polypeptide Raman spectra, we assess the role of key amino acids in different secondary structures. For the recluse spider we develop a highly detailed structural model, featuring seven levels of structural hierarchy. The approaches we develop are directly applicable to other proteinaceous materials.


Subject(s)
Silk , Spiders , Animals , Magnetic Resonance Spectroscopy , Protein Structure, Secondary , Silk/chemistry , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
3.
Nature ; 567(7748): E12, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30837739

ABSTRACT

We would like to correct the sentence in our Letter "However, both our detailed computational analysis (see Supplementary Fig. 2) and past computations13-15 suggest that such enhancements are not anticipated for metallic spheres, and very small increases (by a factor of a few) may be expected for dielectric spheres or metallic cylinders." The work of ref. 13 is not limited to the structures described in this statement but also presents a computational study of radiative heat transfer between rectangular dielectric membranes that is consistent with our experimental and computational analysis, and supports our findings that the blackbody limit can be overcome in the far-field. See accompanying Amendment. The original Letter has not been corrected online.

4.
Nature ; 561(7722): 216-221, 2018 09.
Article in English | MEDLINE | ID: mdl-30177825

ABSTRACT

Radiative heat transfer (RHT) has a central role in entropy generation and energy transfer at length scales ranging from nanometres to light years1. The blackbody limit2, as established in Max Planck's theory of RHT, provides a convenient metric for quantifying rates of RHT because it represents the maximum possible rate of RHT between macroscopic objects in the far field-that is, at separations greater than Wien's wavelength3. Recent experimental work has verified the feasibility of overcoming the blackbody limit in the near field4-7, but heat-transfer rates exceeding the blackbody limit have not previously been demonstrated in the far field. Here we use custom-fabricated calorimetric nanostructures with embedded thermometers to show that RHT between planar membranes with sub-wavelength dimensions can exceed the blackbody limit in the far field by more than two orders of magnitude. The heat-transfer rates that we observe are in good agreement with calculations based on fluctuational electrodynamics. These findings may be directly relevant to various fields, such as energy conversion, atmospheric sciences and astrophysics, in which RHT is important.

5.
J Phys Condens Matter ; 30(2): 025602, 2018 Jan 17.
Article in English | MEDLINE | ID: mdl-29226850

ABSTRACT

We investigate the temperature dependence of infrared properties at nanometer length scales in La0.67Sr0.33MnO3 (LSMO) thin film with a thickness of 47 unit cells grown on SrTiO3 substrate. The infrared nano-imaging experiments were performed using a near-field optical microscope in conjunction with a variable temperature heating stage. The near-field infrared data is consistent with the bulk of the LSMO film undergoing the thermally-driven non-percolative second-order transition from a metallic, ferromagnetic phase to an insulating, paramagnetic phase. We find persistent infrared contrast on the nanoscale that is independent of temperature and which we attribute to two novel phases with different conductivities coexisting in the vicinity of the film-substrate interface. These two coexisting phases at the film-substrate interface do not undergo the metal-insulator transition (MIT) and hence are different from the metallic, ferromagnetic and insulating, paramagnetic phases in the bulk of the film. At temperatures approaching the nominal MIT temperature, repeated scans of the same microscopic area at constant temperature reveal bimodal fluctuation of the near-field infrared amplitude. We interpret this phenomenon as slow, critical fluctuations of the conductivity in the bulk of the LSMO film.

6.
Opt Express ; 25(17): 20421-20430, 2017 Aug 21.
Article in English | MEDLINE | ID: mdl-29041723

ABSTRACT

Scattering-type scanning near-field optical microscopy (S-SNOM) has enormous potential as a spectroscopy tool in the infrared spectral range where it can probe phonon resonances and carrier dynamics at the nanometer lengths scales. However, its applicability is limited by the lack of practical and affordable table-top light sources emitting intense broadband infrared radiation in the 100 cm-1 to 2,500 cm-1 spectral range. This paper introduces a high temperature plasma light source that is both ultra-broadband and has much more radiant power in the infrared spectral range than conventional, table-top thermal light sources such as the globar. We implement this plasma lamp in our near-field optical spectroscopy set up and demonstrate its capability as a broadband infrared nano-spectroscopy light source by obtaining near-field infrared amplitude and phase spectra of the phonon resonances of SiO2 and SrTiO3.

7.
Leukemia ; 31(3): 697-704, 2017 03.
Article in English | MEDLINE | ID: mdl-27654852

ABSTRACT

PR1, an HLA-A2-restricted peptide derived from both proteinase 3 and neutrophil elastase, is recognized on myeloid leukemia cells by cytotoxic T lymphocytes (CTLs) that preferentially kill leukemia and contribute to cytogenetic remission. To evaluate safety, immunogenicity and clinical activity of PR1 vaccination, a phase I/II trial was conducted. Sixty-six HLA-A2+ patients with acute myeloid leukemia (AML: 42), chronic myeloid leukemia (CML: 13) or myelodysplastic syndrome (MDS: 11) received three to six PR1 peptide vaccinations, administered subcutaneously every 3 weeks at dose levels of 0.25, 0.5 or 1.0 mg. Patients were randomized to the three dose levels after establishing the safety of the highest dose level. Primary end points were safety and immune response, assessed by doubling of PR1/HLA-A2 tetramer-specific CTL, and the secondary end point was clinical response. Immune responses were noted in 35 of 66 (53%) patients. Of the 53 evaluable patients with active disease, 12 (24%) had objective clinical responses (complete: 8; partial: 1 and hematological improvement: 3). PR1-specific immune response was seen in 9 of 25 clinical responders versus 3 of 28 clinical non-responders (P=0.03). In conclusion, PR1 peptide vaccine induces specific immunity that correlates with clinical responses, including molecular remission, in AML, CML and MDS patients.


Subject(s)
Cancer Vaccines/immunology , HLA-A2 Antigen/immunology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/immunology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy , Leukemia, Myeloid, Acute/immunology , Leukemia, Myeloid, Acute/therapy , Peptides/immunology , Biomarkers , Cancer Vaccines/administration & dosage , Cancer Vaccines/adverse effects , Epitopes, T-Lymphocyte/immunology , Female , HLA-A2 Antigen/chemistry , Humans , Immunologic Memory , Immunophenotyping , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/mortality , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Male , Peptides/administration & dosage , Peptides/adverse effects , Survival Analysis , T-Cell Antigen Receptor Specificity , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , Treatment Outcome , Vaccination
8.
Phys Rev Lett ; 116(20): 209901, 2016 May 20.
Article in English | MEDLINE | ID: mdl-27258890

ABSTRACT

This corrects the article DOI: 10.1103/PhysRevLett.116.036401.

10.
Phys Rev Lett ; 116(3): 036401, 2016 Jan 22.
Article in English | MEDLINE | ID: mdl-26849604

ABSTRACT

We report the first application of critical cluster techniques to the Mott metal-insulator transition in vanadium dioxide. We show that the geometric universal properties of the metallic and insulating puddles observed by scanning near-field infrared microscopy are consistent with the system passing near criticality of the random field Ising model as temperature is varied. The resulting large barriers to equilibrium may be the source of the unusually robust hysteresis phenomena associated with the metal-insulator transition in this system.

11.
Blood Cancer J ; 6: e396, 2016 Feb 12.
Article in English | MEDLINE | ID: mdl-26871714

ABSTRACT

The safety and efficacy of siltuximab (CNTO 328) was tested in combination with lenalidomide, bortezomib and dexamethasone (RVD) in patients with newly-diagnosed, previously untreated symptomatic multiple myeloma. Fourteen patients were enrolled in the study, eleven of whom qualified to receive therapy. A majority of patients (81.8%) completed the minimal number or more of the four required cycles, while two patients completed only three cycles. The maximum tolerated dose (MTD) of siltuximab with RVD was dose level -1 (siltuximab: 8.3 mg/kg; bortezomib: 1.3 mg/m(2); lenalidomide: 25 mg; dexamethasone: 20 mg). Serious adverse events were grade 3 pneumonia and grade 4 thrombocytopenia, and no deaths occurred during the study or with follow-up (median follow-up 28.1 months). An overall response rate, after 3-4 cycles of therapy, of 90.9% (95% confidence interval (CI): 58.7%, 99.8%) (9.1% complete response (95% CI: 0.2%, 41.3%), 45.5% very good partial response (95% CI: 16.7%, 76.6%) and 36.4% partial response (95% CI: 10.9%, 69.2%)) was seen. Two patients withdrew consent, and nine patients (81.8%) opted for autologous stem cell transplantation.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Multiple Myeloma/drug therapy , Aged , Antibodies, Monoclonal/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bortezomib/administration & dosage , Chromosome Aberrations , Dexamethasone/administration & dosage , Disease Progression , Female , Humans , Lenalidomide , Male , Maximum Tolerated Dose , Middle Aged , Multiple Myeloma/diagnosis , Multiple Myeloma/genetics , Neoplasm Staging , Quality of Life , Thalidomide/administration & dosage , Thalidomide/analogs & derivatives , Treatment Outcome
13.
Ann Oncol ; 26(12): 2490-5, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26416896

ABSTRACT

BACKGROUND: Cutaneous T-cell lymphomas (CTCLs) and its common variants mycosis fungoides (MF) and leukemic Sézary syndrome (SS) are rare extranodal non-Hodgkin's lymphomas. Patients who present with advanced disease and large-cell transformation (LCT) are incurable with standard treatments. In this article, we report the largest single-center experience with allogeneic stem-cell transplantation (SCT) for advanced CTCL. PATIENTS AND METHODS: This is a prospective case series of 47 CTCL patients who underwent allogeneic SCT after failure of standard therapy between July 2001 and September 2013. The Kaplan-Meier method was used to estimate overall survival (OS) and progression-free survival (PFS) curves. The method of Fine and Gray was used to fit regression models to the same covariates for these cumulative incidence data. RESULTS: The Kaplan-Meier estimates of OS and PFS at 4 years were 51% and 26%, respectively. There was no statistical difference in the OS in patients who had MF alone, SS, MF with LCT, or SS with LCT. PFS at 4 years was superior in patients who had SS versus those who did not (52.4% versus 9.9%; P = 0.02). The cumulative incidences of grade 2-4 acute graft-versus-host disease (GVHD) and chronic GVHD were 40% and 28%, respectively. The cumulative nonrelapse mortality rate was 16.7% at 2 years. CONCLUSION: Allogeneic SCT may result in long-term remissions in a subset of patients with advanced CTCL. Although post-SCT relapse rates are high, many patients respond to immunomodulation and achieve durable remissions. CLINICALTRIALSGOV: NCT00506129.


Subject(s)
Hematopoietic Stem Cell Transplantation/methods , Lymphoma, T-Cell, Cutaneous/diagnosis , Lymphoma, T-Cell, Cutaneous/therapy , Skin Neoplasms/diagnosis , Skin Neoplasms/therapy , Adult , Aged , Disease-Free Survival , Female , Follow-Up Studies , Hematopoietic Stem Cell Transplantation/trends , Humans , Male , Middle Aged , Prospective Studies , Transplantation, Homologous/methods , Transplantation, Homologous/trends , Young Adult
14.
Bone Marrow Transplant ; 50(5): 668-72, 2015 May.
Article in English | MEDLINE | ID: mdl-25730192

ABSTRACT

Cardiac involvement in light-chain amyloidosis (AL) predicts poor prognosis and is associated with higher TRM and morbidity during high-dose therapy and auto-SCT (HDT-ASCT). We studied the outcomes of 30 patients with cardiac amyloidosis undergoing HDT-ASCT at our center between January 1998 and March 2012. The median age of the patients was 53 years (range, 36-74) with a median follow-up of 35 months (range, 0.4-97 months). Twenty-seven patients (90%) had more than one organ involved besides the heart with 37% with cardiac stage ⩾3. Melphalan-based conditioning regimen (140-200 mg/m(2)) was used for HDT-ASCT. One-year TRM is 10%. Three-year OS and EFS from HDT-ASCT was 83% and 56.8%, respectively. Cumulative incidence of relapse at 3 years was 38.5%. Negative factors affecting survival included age >60 years, lack of novel induction therapy and BM plasmacytosis >10%. We conclude that HDT-ASCT is well tolerated in patients with high-risk cardiac amyloidosis and can lead to improved overall outcomes.


Subject(s)
Amyloidosis , Heart Diseases , Melphalan/administration & dosage , Myeloablative Agonists/administration & dosage , Stem Cell Transplantation , Transplantation Conditioning , Adult , Aged , Amyloidosis/mortality , Amyloidosis/therapy , Autografts , Disease-Free Survival , Female , Follow-Up Studies , Heart Diseases/mortality , Heart Diseases/therapy , Humans , Male , Middle Aged , Recurrence , Survival Rate
16.
Bone Marrow Transplant ; 49(8): 1036-41, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24887378

ABSTRACT

Optimal treatment approach continues to remain a challenge for systemic light chain amyloidosis (AL). So far, Auto-SCT is the only modality associated with long-term survival. However, failure to show survival benefit in randomized study raises questions regarding its efficacy. We present a comparative outcome analysis of Auto-SCT to conventional therapies (CTR) in AL patients treated over a 14-year period at our institution. Out of the 145 AL amyloidosis patients, Auto-SCT was performed in 80 patients with 1-year non-relapse mortality rate of 12.5%. Novel agents were used as part of induction therapy in 56% of transplant recipients vs 46% of CTR patients. Hematological and organ responses were seen in 74.6% and 39% in the Auto-SCT arm vs 53% and 12% in the CTR arm, respectively. The projected 5-year survival for Auto-SCT vs CTR was 63% vs 38%, respectively. Landmark analysis of patients alive at 1-year after diagnosis showed improved 5-year OS of 72% with Auto-SCT vs 65% in the CTR arm. In the multivariate analysis, age <60 years, induction therapy with novel agents, kidney only involvement and Auto-SCT were associated with improved survival. In conclusion, Auto-SCT is associated with long-term survival for patients with AL amyloidosis.


Subject(s)
Amyloidosis/mortality , Amyloidosis/therapy , Stem Cell Transplantation , Adult , Aged , Aged, 80 and over , Autografts , Disease-Free Survival , Female , Follow-Up Studies , Humans , Immunoglobulin Light Chains , Male , Middle Aged , Time Factors
17.
Br J Cancer ; 111(3): 628-36, 2014 Jul 29.
Article in English | MEDLINE | ID: mdl-24921909

ABSTRACT

BACKGROUND: Insulin/insulin-like growth factor-1 signalling may underlie the promoting effect of type 2 diabetes on cancer. This study examined the association of diabetes, including steroid-induced diabetes (SID), and the impact of anti-diabetic medication on clinical outcomes of multiple myeloma (MM). METHODS: A retrospective review was conducted of 1240 MM patients. Overall survival (OS) and MM disease status prior to death were analysed. RESULTS: Diabetic patients had a significantly shorter OS than non-diabetic patients (median: 65.4 vs 98.7 months). In multivariate analysis, SID was a significant predictor of decreased OS, along with age, comorbidity, MM stage, and cytogenetic abnormalities. Analyzing only the diabetic MM patients, Cox regression showed that metformin predicted an increased OS, whereas use of insulin/analogues predicted a decreased OS. Competing risk analysis showed that DM was associated with increased cumulative incidence of death with progressive MM. Among the diabetics, multivariate regression showed that insulin/analogues were associated with increased, but metformin with decreased death with progressive MM. Potential immortal time bias was evaluated by landmark analyses. CONCLUSIONS: DM, SID in particular, is associated with poor clinical outcomes in MM. Insulin/analogues are associated with poor outcomes, whereas metformin is associated with improved outcomes. No conclusion about causal relationships can be made at this time. Managing hyperglycaemia with non-insulin regimens should be investigated in randomised trials.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Metformin/therapeutic use , Multiple Myeloma/mortality , Adult , Aged , Aged, 80 and over , Comorbidity , Diabetes Mellitus, Type 2/mortality , Disease Progression , Female , Humans , Hypoglycemic Agents/pharmacology , Insulin/pharmacology , Kaplan-Meier Estimate , Male , Metformin/pharmacology , Middle Aged , Multiple Myeloma/therapy , Multivariate Analysis , Proportional Hazards Models , Retrospective Studies , Treatment Outcome , Young Adult
19.
Bone Marrow Transplant ; 49(3): 422-5, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24317125

ABSTRACT

We conducted a retrospective evaluation of response and survival for 293 patients with multiple myeloma treated since June 2000 with primary thalidomide- or bortezomib-based combinations, of whom 207 patients received intensive therapy supported by autologous blood stem cells within the first year. Survival times were calculated after a landmark of 1 year from start of therapy, so that subsequent median survival was 8.9 years for patients with CR, 4.9 years for those with PR and 0.6 year for patients with NR (P<0.001). Multivariate analyses confirmed CR or PR as the major favorable factors with less impact on prognosis for age or disease stage. Both novel agents and high-dose therapy (HDT) resulted in high frequencies of PR or CR, with early HDT useful for many patients with NR or PR in improving response status and subsequent survival.


Subject(s)
Antineoplastic Agents/therapeutic use , Multiple Myeloma/drug therapy , Aged , Boronic Acids/administration & dosage , Bortezomib , Humans , Immunosuppressive Agents/therapeutic use , Middle Aged , Multivariate Analysis , Proportional Hazards Models , Pyrazines/administration & dosage , Remission Induction , Retrospective Studies , Stem Cell Transplantation , Thalidomide/administration & dosage , Transplantation Conditioning/methods , Transplantation, Autologous , Treatment Outcome
20.
Bone Marrow Transplant ; 48(9): 1218-23, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23503529

ABSTRACT

Disseminated adenoviral infection (AI) is associated with profound immunosuppression and poor outcome after allogeneic hematopoietic SCT (allo-HSCT). A better understanding of AI in allo-HSCT recipients can serve as a basis to develop more effective management strategies. We evaluated all adult patients who received allo-HSCT at MD Anderson Cancer Center between 1999 and 2008. Among the 2879 allo-HSCT patients, 73 (2.5%) were diagnosed with AI. Enteritis (26%) and pneumonia (24%) were the most common clinical manifestations; pneumonia was the most common cause of adenovirus-associated death. A multivariable Bayesian logistic regression showed that when the joint effects of all covariates were accounted for, cord blood transplant, absolute lymphocyte count (ALC) ≤ 200/mm(3) and male gender were associated with a higher probability of disseminated AI. The OS was significantly worse for patients with AI that was disseminated rather than localized (median of 5 months vs median of 28 months, P<0.001) and for patients with ALC ≤ 200/mm(3) (P<0.001). Disseminated AI, in patients who received allo-HSCT, is a significant cause of morbidity and mortality. Strategies for early diagnosis and intervention are essential, especially for high-risk patients.


Subject(s)
Adenoviridae Infections/etiology , Adenoviridae/isolation & purification , Hematopoietic Stem Cell Transplantation/adverse effects , Transplantation Conditioning/adverse effects , Adenoviridae Infections/immunology , Adenoviridae Infections/pathology , Adult , Aged , Aged, 80 and over , Female , HLA Antigens/immunology , Humans , Male , Middle Aged , Retrospective Studies , Transplantation, Homologous , Treatment Outcome , Young Adult
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