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1.
Br J Haematol ; 199(2): 190-204, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35796524

RESUMO

For patients with newly diagnosed multiple myeloma, survival outcomes continue to improve significantly: however, nearly all patients will relapse following induction treatment. Optimisation of induction therapy is essential to provide longer term disease control and the current standard of care for most patients incorporates an immunomodulatory agent and proteasome inhibitor, most commonly lenalidomide and bortezomib in combination with dexamethasone (RVD), with maintenance until progression. Historically there has been limited access to RVD as an induction strategy outside of the United States; fortunately, there is now increasing access worldwide. This review discusses the rationale for use of RVD as induction therapy and aims to provide guidance in prescribing this regimen in order to optimise efficacy while minimising the toxicities of treatment. We also highlight the increasing evidence for the utility of addition of a monoclonal antibody to the RVD backbone to deepen responses and potentially provide longer disease control.


Assuntos
Mieloma Múltiplo , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bortezomib/efeitos adversos , Dexametasona , Humanos , Quimioterapia de Indução , Lenalidomida , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia/etiologia , Inibidores de Proteassoma/uso terapêutico , Estados Unidos
2.
Am J Pathol ; 190(2): 388-399, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31955792

RESUMO

Preterm premature rupture of membranes (PPROM) and thrombin generation by decidual cell-expressed tissue factor often accompany abruptions. Underlying mechanisms remain unclear. We hypothesized that thrombin-induced colony-stimulating factor-2 (CSF-2) in decidual cells triggers paracrine signaling via its receptor (CSF2R) in trophoblasts, promoting fetal membrane weakening and abruption-associated PPROM. Decidua basalis sections from term (n = 10), idiopathic preterm birth (PTB; n = 8), and abruption-complicated pregnancies (n = 8) were immunostained for CSF-2. Real-time quantitative PCR measured CSF2 and CSF2R mRNA levels. Term decidual cell (TDC) monolayers were treated with 10-8 mol/L estradiol ± 10-7 mol/L medroxyprogesterone acetate (MPA) ± 1 IU/mL thrombin pretreatment for 4 hours, washed, and then incubated in control medium with estradiol ± MPA. TDC-derived conditioned media supernatant effects on fetal membrane weakening were analyzed. Immunostaining localized CSF-2 primarily to decidual cell cytoplasm and cytotrophoblast cell membranes. CSF-2 immunoreactivity was higher in abruption-complicated or idiopathic PTB specimens versus normal term specimens (P < 0.001). CSF2 mRNA was higher in TDCs versus cytotrophoblasts (P < 0.05), whereas CSF2R mRNA was 1.3 × 104-fold higher in cytotrophoblasts versus TDCs (P < 0.001). Thrombin enhanced CSF-2 secretion in TDC cultures fourfold (P < 0.05); MPA reduced this effect. Thrombin-pretreated TDC-derived conditioned media supernatant weakened fetal membranes (P < 0.05), which MPA inhibited. TDC-derived CSF-2, acting via trophoblast-expressed CSFR2, contributes to thrombin-induced fetal membrane weakening, eliciting abruption-related PPROM and PTB.


Assuntos
Descolamento Prematuro da Placenta/fisiopatologia , Decídua/patologia , Membranas Extraembrionárias/patologia , Ruptura Prematura de Membranas Fetais/patologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Nascimento Prematuro/etiologia , Trombina/farmacologia , Decídua/efeitos dos fármacos , Decídua/metabolismo , Membranas Extraembrionárias/metabolismo , Feminino , Ruptura Prematura de Membranas Fetais/etiologia , Ruptura Prematura de Membranas Fetais/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Humanos , Gravidez , Nascimento Prematuro/metabolismo , Nascimento Prematuro/patologia , Transdução de Sinais , Trofoblastos/efeitos dos fármacos , Trofoblastos/metabolismo , Trofoblastos/patologia
3.
Mult Scler ; 27(13): 2112-2115, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33870788

RESUMO

BACKGROUND: Given the increasing numbers of multiple sclerosis (MS) patients undergoing autologous haematopoietic stem cell transplant (AHSCT) worldwide, and with women of childbearing age overrepresented in the target population, it is increasingly important to review fertility and pregnancy outcomes following AHSCT. OBJECTIVE: To evaluate the rate of pregnancy and complications post-AHSCT for MS. METHOD: Retrospective evaluation of the rate of pregnancy and associated complications in a cohort of patients post-AHSCT with BEAM conditioning for MS since 2010 in a tertiary referral centre. RESULTS: In our ongoing Phase 2 trial of AHSCT for MS, 55 patients have undergone AHSCT with 30 females being of childbearing age at time of transplantation. Four pregnancies occurred following AHSCT. Two pregnancies were carried to term. No maternal or neonatal complications were reported in either case. Two pregnancies were not carried to term due to elective terminations. Both of these patients became pregnant unexpectedly 2 years following AHSCT. Of the 21 male patients, one patient has fathered three children since his AHSCT. There were no newborn complications. CONCLUSIONS: This is the first report to our knowledge on fertility outcomes in both sexes post-AHSCT for MS. Patients of both sexes should be counselled prior to treatment on infertility and contraceptive use.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Esclerose Múltipla , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Esclerose Múltipla/terapia , Gravidez , Estudos Retrospectivos , Condicionamento Pré-Transplante , Transplante Autólogo , Resultado do Tratamento
4.
J Neurol Neurosurg Psychiatry ; 90(5): 514-521, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30538138

RESUMO

BACKGROUND: Autologous haematopoietic stem cell transplantation (AHSCT) has been explored as a therapeutic intervention in multiple sclerosis (MS) over the last two decades; however, prospective clinical trials of the most common myeloablative conditioning regimen, BEAM, are limited. Furthermore, patient selection, optimal chemotherapeutic regimen and immunological changes associated with disease response require ongoing exploration. We present the outcomes, safety and immune reconstitution (IR) of patients with active, treatment refractory MS. METHODS: This study was a single-centre, phase II clinical trial of AHSCT for patients with active relapsing remitting (RRMS) and secondary progressive MS (SPMS). Patients underwent AHSCT using BEAM (carmustine, etoposide, cytarabine, melphalan)+antithymocyte globulin chemotherapeutic regimen. OUTCOMES: The primary outcome was event-free survival (EFS); defined as no clinical or radiological relapses and no disability progression. Multiparameter flow cytometry was performed for evaluation of post-transplant IR in both MS and lymphoma patients receiving the same chemotherapy regimen. RESULTS: Thirty-five patients (20 RRMS, 15 SPMS) completed AHSCT, with a median follow-up of 36 months (range 12-66). The median Expanded Disability Status Scores (EDSS) was 6 (2-7) and patients had failed a median of 4 (2-7) disease modifying therapies. 66% failed treatment with natalizumab. EFS at 3 years was 60%, (70% RRMS). Sustained improvement in EDSS was seen in 15 (44%) of patients. There was no treatment-related mortality. A sustained rise in CD39+ T regulatory cells, immunosuppressive CD56hi natural killer cells and ablation of proinflammatory mucosal-associated invariant T cells was seen for 12 months following AHSCT in patients with MS. These changes did not occur in patients with lymphoma receiving the same chemotherapy for AHSCT. CONCLUSIONS: The EFS in our MS cohort is significantly greater than other high-efficacy immunosuppressive therapies and similar to other AHSCT studies despite a more heavily pretreated cohort. TRIAL REGISTRATION NUMBER: ACTRN12613000339752.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Esclerose Múltipla Crônica Progressiva/terapia , Esclerose Múltipla Recidivante-Remitente/terapia , Adulto , Soro Antilinfocitário/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carmustina/uso terapêutico , Citarabina/uso terapêutico , Etoposídeo/uso terapêutico , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Estudos Prospectivos , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
5.
Am J Obstet Gynecol ; 217(6): 695.e1-695.e14, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29031893

RESUMO

BACKGROUND: The progestogen 17-α hydroxyprogesterone caproate (17-OHPC) is 1 of only 2 agents recommended for clinical use in the prevention of spontaneous preterm delivery, and studies of its efficacy have been conflicting. We have developed an in-vitro model to study the fetal membrane weakening process that leads to rupture in preterm premature rupture of the fetal membranes (pPROM). Inflammation/infection associated with tumor necrosis factor-α (TNF-α) induction and decidual bleeding/abruption associated thrombin release are leading causes of preterm premature rupture of the fetal membranes. Both agents (TNF-α and thrombin) cause fetal membrane weakening in the model system. Furthermore, granulocyte-macrophage colony-stimulating factor (GM-CSF) is a critical intermediate for both TNF-α and thrombin-induced fetal membrane weakening. In a previous report, we demonstrated that 3 progestogens, progesterone, 17-alpha hydroxyprogesterone (17-OHP), and medroxyprogesterone acetate (MPA), each inhibit both TNF-α- and thrombin-induced fetal membrane weakening at 2 distinct points of the fetal membrane weakening pathway. Each block both the production of and the downstream action of the critical intermediate granulocyte-macrophage colony-stimulating factor. OBJECTIVE: The objective of the study was to characterize the inhibitory effects of 17-OHPC on TNF-α- and thrombin-induced fetal membrane weakening in vitro. STUDY DESIGN: Full-thickness human fetal membrane fragments from uncomplicated term repeat cesarean deliveries were mounted in 2.5 cm Transwell inserts and cultured with/without 17-alpha hydroxyprogesterone caproate (10-9 to 10-7 M). After 24 hours, medium (supernatant) was removed and replaced with/without the addition of tumor necrosis factor-alpha (20 ng/mL) or thrombin (10 U/mL) or granulocyte-macrophage colony-stimulating factor (200 ng/mL). After 48 hours of culture, medium from the maternal side compartment of the model was assayed for granulocyte-macrophage colony-stimulating factor and the fetal membrane fragments were rupture strength tested. RESULTS: Tumor necrosis factor-alpha and thrombin both weakened fetal membranes (43% and 62%, respectively) and increased granulocyte-macrophage colony-stimulating factor levels (3.7- and 5.9-fold, respectively). Pretreatment with 17-alpha hydroxyprogesterone caproate inhibited both tumor necrosis factor-alpha- and thrombin-induced fetal membrane weakening and concomitantly inhibited the induced increase in granulocyte-macrophage colony-stimulating factor in a concentration-dependent manner. However, contrary to our prior reports regarding progesterone and other progestogens, 17-alpha hydroxyprogesterone caproate did not also inhibit granulocyte-macrophage colony-stimulating factor-induced fetal membrane weakening. CONCLUSION: 17-Alpha hydroxyprogesterone caproate blocks tumor necrosis factor-alpha- and thrombin-induced fetal membrane weakening by inhibiting the production of granulocyte-macrophage colony-stimulating factor. However, 17-alpha hydroxyprogesterone caproate did not also inhibit granulocyte-macrophage colony-stimulating factor-induced weakening. We speculate that progestogens other than 17-alpha hydroxyprogesterone caproate may be more efficacious in preventing preterm premature rupture of the fetal membranes-related spontaneous preterm birth.


Assuntos
Membranas Extraembrionárias/efeitos dos fármacos , Ruptura Prematura de Membranas Fetais/prevenção & controle , Hidroxiprogesteronas/farmacologia , Progestinas/farmacologia , Caproato de 17 alfa-Hidroxiprogesterona , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Hemostáticos/farmacologia , Humanos , Técnicas In Vitro , Modelos Biológicos , Gravidez , Nascimento Prematuro/prevenção & controle , Trombina/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
6.
Am J Obstet Gynecol ; 213(4): 520.e1-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26070709

RESUMO

OBJECTIVE: Inflammation/infection and abruption are leading causes of preterm premature rupture of the membranes. Recently, we identified granulocyte-macrophage colony-stimulating factor (GM-CSF) as a critical mediator of both tumor necrosis factor-α- (TNF; modeling inflammation) and thrombin-induced (modeling abruption) weakening of the fetal membranes. We found that (1) TNF and thrombin both induced GM-CSF in the choriodecidua, (2) blockade of GM-CSF action with neutralizing antibodies inhibited both TNF- and thrombin-induced fetal membrane weakening, and (3) GM-CSF alone induced fetal membrane weakening. GM-CSF is thus part of an overlap of the inflammation and abruption-induced fetal membrane weakening pathways. The effects of progesterone analogs on the pathways by which fetal membranes are weakened have not been investigated. We examined the effects of progesterone, medroxyprogesterone acetate (MPA) and 17α-hydroxyprogesterone (HP) on TNF- and thrombin-induced fetal membrane weakening. STUDY DESIGN: Full-thickness fetal membranes from uncomplicated term repeat cesarean deliveries were mounted in Transwell inserts in Minimum Essential Medium alpha and incubated at 37°C in 5% CO2. The choriodecidua side of the fetal membrane fragments were preincubated with progesterone, MPA, HP, or vehicle for 24 hours. Fetal membranes were then exposed to TNF, thrombin, or GM-CSF on the choriodecidua side for an additional 48 hours. The fetal membrane tissues were then strength tested, and medium from the choriodecidua and amnion compartments was assayed for GM-CSF content. RESULTS: TNF and thrombin both weakened fetal membranes and elevated media GM-CSF levels on the choriodecidua side of the fetal membrane. Pretreatment with progesterone, MPA, or HP inhibited both TNF- and thrombin-induced fetal membrane weakening and also inhibited the induced increase in GM-CSF. GM-CSF decreased fetal membrane rupture strength by 68%, which was inhibited by progestogen pretreatment with a potency order: progesterone

Assuntos
Córion/efeitos dos fármacos , Decídua/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Hemostáticos/farmacologia , Progesterona/farmacologia , Progestinas/farmacologia , Trombina/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , 17-alfa-Hidroxiprogesterona/farmacologia , Membranas Extraembrionárias/efeitos dos fármacos , Feminino , Ruptura Prematura de Membranas Fetais , Humanos , Técnicas In Vitro , Acetato de Medroxiprogesterona/farmacologia , Gravidez
7.
J Biomech Eng ; 136(11)2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25171138

RESUMO

Puncture testing has been applied in several studies for the mechanical characterization of human fetal membrane (FM) tissue, and significant knowledge has been gained from these investigations. When comparing results of mechanical testing (puncture, inflation, and uniaxial tension), we have observed discrepancies in the rupture sequence of FM tissue and significant differences in the deformation behavior. This study was undertaken to clarify these discrepancies. Puncture experiments on FM samples were performed to reproduce previous findings, and numerical simulations were carried out to rationalize particular aspects of membrane failure. The results demonstrate that both rupture sequence and resistance to deformation depend on the samples' fixation. Soft fixation leads to slippage in the clamping, which reduces mechanical loading of the amnion layer and results in chorion rupturing first. Conversely, the stiffer, stronger, and less extensible amnion layer fails first if tight fixation is used. The results provide a novel insight into the interpretation of ex vivo testing as well as in vivo membrane rupture.


Assuntos
Membranas Extraembrionárias , Teste de Materiais , Fenômenos Mecânicos , Punções , Fenômenos Biomecânicos , Membranas Extraembrionárias/lesões , Feminino , Análise de Elementos Finitos , Humanos , Gravidez , Estresse Mecânico
8.
Cytotherapy ; 15(2): 224-30, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23321333

RESUMO

BACKGROUND AIMS: Expansion of hemopoietic stem cells (HSCs) in vitro is a potential strategy for improving transplant outcomes, but expansion methods tend to promote differentiation and loss of stem cell potential. Aryl hydrocarbon receptor antagonists (AhRAs) have recently been shown to protect HSC stemness during expansion; however, little is known of the T-cell regenerative capacity of AhRA-expanded HSCs. In this study, we confirm the protective effect of two commercially available AhRA compounds on HSCs from both cord blood (CB) and adult samples and assess the T-lymphocyte potential of the expanded cells. METHODS: Adult mobilized peripheral blood and CB samples were purified to CD34(+) cells, which were expanded in vitro with cytokines and AhRAs. After 14 d, CD34(+) cells were re-isolated and then grown on in OP9Delta co-culture under conditions that allow T-lymphocyte differentiation. Cells were monitored weekly for T-lineage markers by flow cytometry. RESULTS: Both AhRA compounds promoted maintenance of CD34 expression during 2 weeks of proliferation with growth factors, although adult cells proliferated markedly less than CB cells. AhRA-expanded CD34(+) cells from CB differentiated to T cells on OP9Delta co-culture with the same rate and time course as untreated cells. Adult cells, by contrast, had reduced differentiation to T cells, with donor-dependent variable responses. CONCLUSIONS: This study shows that whereas AhRA treatment is effective in CB samples, expansion of adult HSCs is less successful and reflects their inherent poor potential in T-cell generation.


Assuntos
Compostos Azo/administração & dosagem , Diferenciação Celular , Sangue Fetal/efeitos dos fármacos , Transplante de Células-Tronco Hematopoéticas , Pirazóis/administração & dosagem , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Antígenos CD34/metabolismo , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Proliferação de Células/efeitos dos fármacos , Técnicas de Cocultura , Sangue Fetal/citologia , Citometria de Fluxo , Humanos , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos
9.
Ann Clin Transl Neurol ; 9(2): 206-220, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35106961

RESUMO

OBJECTIVE: Autologous haematopoietic stem cell transplantation (AHSCT) has the potential to induce sustained periods of disease remission in multiple sclerosis (MS), which is an inflammatory disease of the central nervous system (CNS) characterised by demyelination and axonal degeneration. However, the mechanisms associated with durable treatment responses in MS require further elucidation. METHODS: To characterise the longer term immune reconstitution effects of AHSCT at 24 and 36 months (M) post-transplant, high-dimensional immunophenotyping of peripheral blood mononuclear cells from 22 MS patients was performed using two custom-designed 18-colour flow cytometry panels. RESULTS: The higher baseline frequencies of specific pro-inflammatory immune cells (T-helper-17 (Th17) cells, mucosal-associated invariant T-cells and CNS-homing T-conventional (T-conv) cells observed in MS patients were decreased post-AHSCT by 36M. This was accompanied by a post-AHSCT increase in frequencies and absolute counts of immunoregulatory CD56hi natural killer cells at 24M and terminally differentiated CD8+ CD28- CD57+ cells until 36M. A sustained increase in the proportion of naïve B-cells, with persistent depletion of memory B-cells and plasmablasts was observed until 36M. Reconstitution of the B-cell repertoire was accompanied by a reduction in the frequency of circulating T-follicular helper cells (cTfh) expressing programmed cell death-1 (PD1+ ) at 36M. Associations between frequency dynamics and clinical outcomes indicated only responder patients to exhibit a decrease in Th17, CNS-homing T-conv and PD1+ cTfh pro-inflammatory subsets at 36M, and an increase in CD39+ T-regulatory cells at 24M. INTERPRETATION: AHSCT induces substantial recalibration of pro-inflammatory and immunoregulatory components of the immune system of MS patients for up to 36M post-transplant.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucócitos Mononucleares , Esclerose Múltipla/sangue , Esclerose Múltipla/imunologia , Esclerose Múltipla/terapia , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Adulto Jovem
10.
Front Immunol ; 12: 782935, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35126353

RESUMO

Autologous haematopoietic stem cell transplantation (AHSCT) is a therapeutic option for haematological malignancies, such as non-Hodgkin's lymphoma (NHL), and more recently, for autoimmune diseases, such as treatment-refractory multiple sclerosis (MS). The immunological mechanisms underlying remission in MS patients following AHSCT likely involve an anti-inflammatory shift in the milieu of circulating cytokines. We hypothesised that immunological tolerance in MS patients post-AHSCT is reflected by an increase in anti-inflammatory cytokines and a suppression of proinflammatory cytokines in the patient blood. We investigated this hypothesis using a multiplex-ELISA assay to compare the concentrations of secreted cytokine in the peripheral blood of MS patients and NHL patients undergoing AHSCT. In MS patients, we detected significant reductions in proinflammatory T helper (Th)17 cytokines interleukin (IL)-17, IL-23, IL-1ß, and IL-21, and Th1 cytokines interferon (IFN)γ and IL-12p70 in MS patients from day 8 to 24 months post-AHSCT. These changes were not observed in the NHL patients despite similar pre-conditioning treatment for AHSCT. Some proinflammatory cytokines show similar trends in both cohorts, such as IL-8 and tumour necrosis factor (TNF)-α, indicating a probable treatment-related AHSCT response. Anti-inflammatory cytokines (IL-10, IL-4, and IL-2) were only transiently reduced post-AHSCT, with only IL-10 exhibiting a significant surge at day 14 post-AHSCT. MS patients that relapsed post-AHSCT exhibited significantly elevated levels of IL-17 at 12 months post-AHSCT, unlike non-relapse patients which displayed sustained suppression of Th17 cytokines at all post-AHSCT timepoints up to 24 months. These findings suggest that suppression of Th17 cytokines is essential for the induction of long-term remission in MS patients following AHSCT.


Assuntos
Citocinas/sangue , Esclerose Múltipla/sangue , Adulto , Idoso , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Interleucina-12/sangue , Interleucinas/sangue , Linfoma não Hodgkin/sangue , Masculino , Pessoa de Meia-Idade , Células Th17/metabolismo , Transplante Autólogo/efeitos adversos , Adulto Jovem
11.
J Nanosci Nanotechnol ; 10(2): 1278-85, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20352789

RESUMO

The paper will discuss the effect of pulsing single or two unbalanced magnetrons in a closed magnetic field configuration on the structure and properties of tribological Cr-Al-N coatings. Nanocrystalline Cr-Al-N coatings were reactively deposited from Cr and Al elemental targets using two unbalanced magnetrons, which were powered in both dc, pulsing only Al target and asynchronously pulsing both Cr and Al targets at 100 kHz and 50% duty cycle conditions. The ion energy distributions of these deposition and pulsing conditions were characterized using a Hiden Electrostatic QuadruPole Plasma Analyzer. It was found that pulsing two magnetrons asynchronously at 100 kHz and 50% duty cycle produced higher ion energies and significant increased ion fluxes than pulsing none or pulsing only one (Al) target. The structure and properties of Cr-Al-N coatings synthesized under different dc and pulsing conditions were investigated using X-ray diffraction, scanning electron microscopy, nanoindentation and ball-on-disk wear test, and were correlated with the effects of ion energies and ion flux regimes observed in the plasma diagnostics. The advantages of using pulsed magnetron sputtering producing different energetic ion regimes to enhance the ion bombardment on the growing films and therefore achieving the improved density, refinement of grain size and properties are illustrated.

12.
Obstet Gynecol Clin North Am ; 47(1): 147-162, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32008665

RESUMO

Fetal membranes (FMs) play a role in pregnancy maintenance and promoting parturition at term. The FMs are not just part of the placenta, structurally or functionally. Although attached to the placenta, the amnion has a separate embryologic origin, and the chorion deviates from the placenta by the first month of pregnancy. Other than immune protection, these FM functions are not those of the placenta. FM dysfunction is associated with and may cause adverse pregnancy outcomes. Ongoing research may identify biomarkers for pending preterm premature rupture of the FMs as well as therapeutic agents, to prevent it and resulting preterm birth.


Assuntos
Membranas Extraembrionárias/diagnóstico por imagem , Ruptura Prematura de Membranas Fetais/diagnóstico , Placenta/diagnóstico por imagem , Nascimento Prematuro , Feminino , Humanos , Gravidez
13.
Obstet Gynecol Clin North Am ; 47(4): 523-544, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33121643

RESUMO

Using a novel in vitro model system combining biochemical/histologic with bioengineering approaches has provided significant insights into the physiology of fetal membrane weakening and rupture along with potential mechanistic reasons for lack of efficacy of currently clinically used agents to prevent preterm premature rupture of the membranes (pPROM) and preterm births. Likewise, the model has also facilitated screening of agents with potential for preventing pPROM and preterm birth.


Assuntos
Membranas Extraembrionárias/metabolismo , Ruptura Prematura de Membranas Fetais/metabolismo , Ruptura Prematura de Membranas Fetais/prevenção & controle , Membranas Extraembrionárias/fisiopatologia , Feminino , Ruptura Prematura de Membranas Fetais/fisiopatologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Recém-Nascido , Modelos Biológicos , Gravidez , Nascimento Prematuro/prevenção & controle , Progesterona/metabolismo , Ácido Tióctico/metabolismo , Trombina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
14.
Bone Marrow Transplant ; 55(5): 857-866, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31619766

RESUMO

Autologous haematopoietic stem cell transplantation shows increasing promise as a therapeutic option for patients with treatment-refractory autoimmune disease, particularly systemic sclerosis and multiple sclerosis. However, this intensive chemotherapy-based procedure is not always possible due to potential treatment toxicities and comorbidities. The biological mechanisms of how this procedure induces long-term remission in autoimmune disease are increasingly understood. The focus of this review is on recent research findings on the role of CD4+ T regulatory cells (Tregs) in resetting the immune system leading to the eradication of the autoimmune disease after transplantation. Discovery of the precise mechanisms of this process will allow development of novel Treg-based therapies and thus avoid the need for intensive chemotherapy-based treatment for these autoimmune diseases in the future.


Assuntos
Doenças Autoimunes , Transplante de Células-Tronco Hematopoéticas , Doenças Autoimunes/terapia , Humanos , Regeneração , Linfócitos T Reguladores , Transplante Autólogo
15.
Placenta ; 89: 1-7, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31665659

RESUMO

INTRODUCTION: We have previously demonstrated two associations of PPROM, (1) inflammation/infection (modeled by tumor necrosis factor (TNF)) and (2) decidual bleeding (modeled by thrombin), both decrease fetal membrane (FM) rupture strength in-vitro. Furthermore, Granulocyte-Macrophage-Colony-Stimulating-Factor (GM-CSF) induced by both TNF and thrombin is a critical intermediate, necessary and sufficient for weakening by either agent. The amnion is the strength component of FM and must weaken for FM to rupture. It is unclear whether GM-CSF weakens amnion (AM) directly, or initially targets choriodecidua (CD) which secondarily releases agents to act on amnion. METHODS: Full thickness FM fragments were treated with/without GM-CSF. Some were preincubated with alpha-lipoic acid (LA), a known inhibitor of FM weakening. The FM fragments were then strength-tested. Separately, FM fragments were initially separated to AM and CD. AM fragments were cultured with Medium ± GM-CSF and then strength-tested. In other experiments, CD fragments were cultured with Medium, GM-CSF, LA, or LA + GM-CSF. Conditioned medium from each group was then incubated with AM. AM was then strength-tested. Matrix Metalloproteinases (MMPs) and Tissue Inhibitors of Matrix Metalloproteinases (TIMPs) were analyzed by Mutiplex Elisa. RESULTS: GM-CSF weakened intact FM which was blocked by LA. GM-CSF did not weaken isolated AM. However, GM-CSF conditioned CD media weakened AM and this weakening was inhibited by LA. GM-CSF treatment of CD increased MMPs 2, 9, and 10, and decreased TIMPs 1-3. LA reversed these effects. CONCLUSIONS: GM-CSF does not weaken amnion directly; GM-CSF acts on CD to increase proteases and decrease anti-proteases which secondarily weaken the amnion.


Assuntos
Âmnio/efeitos dos fármacos , Córion/efeitos dos fármacos , Ruptura Prematura de Membranas Fetais/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Metaloproteinases da Matriz/metabolismo , Inibidores Teciduais de Metaloproteinases/metabolismo , Âmnio/metabolismo , Córion/metabolismo , Meios de Cultivo Condicionados , Feminino , Humanos , Gravidez , Ácido Tióctico/farmacologia
16.
J Nanosci Nanotechnol ; 9(6): 3514-23, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19504877

RESUMO

The main objective of this research is to design an optimized 'coating system' that extends die life by minimizing premature die failure. The concept of the multilayer coating system with desired combinations of different kinds of single-layer coatings was introduced. A pulsed closed field unbalanced magnetron sputtering (P-CFUBMS) deposition system has been used to deposit Cr-CrxNy-Cr1-xAlxN compositionally graded multilayer coating structures. In this study, three power law scenarios have been adopted to vary the aluminum concentration in the graded Cr1-xAlxN layer: (i) p = 1, the aluminum concentration was increased linearly in the Cr1-xAlxN layer. (ii) p = 0.2, the Cr1-xAlxN layer is an aluminum-rich graded layer, and (iii) p = 2, the Cr1-xAlxN layer is a chromium-rich graded layer. It was found that all the graded coatings exhibit lower residual stress and higher adhesion strength than the homogeneous Cr1-xAlxN (x = 0.585) film. However, different power law grading architectures have significant influence on the hardness and wear resistance of the films. When p = 2 and p = 1, the graded films exhibited relatively low hardness values (24 and 26 GPa respectively) and high COF (0.55 to 0.60). When p = 0.2 the graded film exhibited both high hardness (34 GPa) and good wear resistance (COF = 0.45) due to the structural consistency in the graded zone. The paper discusses the correlation between the pulsing parameters and coating architecture with the resulting nanostructure and tribological properties of this Cr-CrxNy-Cr1-xAlxN coating system.

17.
J Nanosci Nanotechnol ; 9(7): 4073-84, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19916411

RESUMO

Nanostructured, nanocomposite binary (TiC-a:C), ternary (Cr-Al-N), quaternary (Ti-B-C-N) and quinternary (Ti-Si-B-C-N) multicomponent films have been deposited using unbalanced magnetron sputtering (UBMS) and closed field unbalanced magnetron sputtering (CFUBMS) from both elemental and composite targets. Approaches to control the film chemistry, volume fraction and size of the multicomponent species, and pulsed ion energy (ion flux) bombardment to tailor the structure and properties of the films for specific tribological applications, e.g., low friction coefficient and low wear rate, are emphasized. The synthesized films are characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), nanoindentation, and microtribometry. The relationships between processing parameters (pulsed ion energy and ion flux), thin film microstructure, mechanical and tribological properties are being investigated in terms of the nanocrystalline-nanocrystalline and nanocrystalline-amorphous composite thin film systems that are generated. In the Ti-Si-B-C-N films, nanocomposites of solid solutions, e.g., nanosized (Ti,C,N)B2 and Ti(C,N) crystallites are embedded in an amorphous TiSi2 and SiC matrix including some carbon, SiB4, BN, CN(x), TiO2 and B2O3 components. The Ti-Si-B-C-N coating with up to 150 W Si target power exhibited a hardness of about 35 GPa, a high H/E ratio of 0.095, and a low wear rate of from approximately 3 to approximately 10 x 10(-6) mm3/(Nm). In another aspect, using increased ion energy and ion flux, which are generated by pulsing the power of the target(s) in a closed field arrangement, to provide improved ion bombardment on tailoring the structure and properties of TiC-a:C and Cr-Al-N coatings are demonstrated. It was found that highly energetic species (up to hundreds eV) were found in the plasma by pulsing the power of the target(s) during magnetron sputtering. Applying higher pulse frequency and longer reverse time (lower duty cycle) will result in higher ion energy and ion flux in the plasma, which can be utilized to improve the film structure and properties. For example, optimum properties of the TiC-a:C coating were a hardness of 35 to 40 GPa and a COF of 0.2 to 0.22 for moderate maximum ion energies of 70 to 100 eV, and a super high hardness of 41 GPa and low wear rate of 3.41 x 10(-6) mm3N(-1) m(-1) was obtained for Cr-Al-N coatings deposited with a maximum ion energy of 122 eV. These conditions can be achieved by adjusting the pulsing parameters and target voltages. However, the pulsed ion energy together with the applied substrate bias are need to be carefully controlled in order to avoid excessive ion bombardment (e.g., the maximum ion energy is larger than 180 eV in the current study), which will responsible for an increase in point and line defects, and high residual stress in the crystalline structure.

18.
Curr Opin Support Palliat Care ; 13(4): 394-401, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31599815

RESUMO

PURPOSE OF REVIEW: In this review, we summarize the recently published literature that demonstrates the efficacy and safety of autologous haematopoietic stem cell therapy (AHSCT) in multiple sclerosis (MS) and highlight the importance of supportive care required for the safe and well-tolerated delivery of AHSCT. RECENT FINDINGS: MS is an autoimmune inflammatory and degenerative disorder of the central nervous system (CNS). In the majority of patients, the illness runs a relapsing remitting course (RRMS), culminating in a secondary progressive phase with gradual accumulation of fixed disabilities. Currently available disease-modifying therapies suppress CNS inflammation but have a limited effect on preventing disease progression for which there remains no effective therapy. Over the last two decades, there has been increasing evidence that AHSCT is a highly effective therapeutic strategy for treatment-resistant inflammatory types of MS, especially RRMS. Concerns about the safety of AHSCT in MS, usually a nonlife-threatening disease, have previously limited its use. However, AHSCT can now be delivered safely with major long-term benefits because of increasing transplant centre experience, judicious patient selection and good supportive care. SUMMARY: MS is currently the fastest growing indication for AHSCT in Europe. Supportive care before, during and after the transplant period is key to the successful delivery of AHSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Esclerose Múltipla/terapia , Progressão da Doença , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Transplante Autólogo
19.
PLoS One ; 14(12): e0225767, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31790466

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is capable of transient viremia and extrapulmonary dissemination. Recently, this virus has been identified in fetal cord blood, suggesting the possibility of in utero acquisition in humans. Here, we assess permissivity and kinetics of RSV replication in primary human placental cells, examine their potential to transfer this infection to neighboring cells, and measure the inflammatory response evoked by the virus. METHODS AND FINDINGS: Human placental villus tissue was collected immediately upon delivery and processed for isolation of placental cytotrophoblast, fibroblast, and macrophage (Hofbauer) cells. Isolated cells were infected with a recombinant RSV-A2 strain (rrRSV) expressing red fluorescent protein (RFP) and analyzed by fluorescence microscopy, Western blot, and quantitative PCR (qPCR). Based on RFP expression, rrRSV exhibited differential tropism for the three major placental cell types. Placental fibroblasts and Hofbauer cells were permissive and supported productive rrRSV replication. While infected cytotrophoblast cells expressed viral glycoprotein (G protein), only limited RSV replication was detected. Importantly, qPCR and fluorescence-focused unit assay revealed that the viral progeny remains trapped within infected Hofbauer cells for up to 30 days, with no release into surrounding media. Yet, Hofbauer cells passed the infection onto overlaid naïve 16HBE cells, suggesting contact-dependent trans-infection. Lastly, a significant increase in proinflammatory cytokines, particularly IL-6, TNF-alpha, and IFN-gamma was measured in the supernatant of infected Hofbauer cells by multiplex cytokine assay and conventional ELISA. CONCLUSIONS: This study demonstrates that RSV can replicate in human placenta, exhibits differential tropism for distinct placental cell types, can be stored and transferred to neighboring cells by Hofbauer cells, and elicits an inflammatory response. It also supports the hypothesis that this respiratory virus can be vertically transferred to the fetus and potentially affect its development and the outcome of pregnancies.


Assuntos
Placenta/patologia , Placenta/virologia , Vírus Sincicial Respiratório Humano/fisiologia , Tropismo , Citocinas/metabolismo , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Cinética , Gravidez , Infecções por Vírus Respiratório Sincicial/patologia , Infecções por Vírus Respiratório Sincicial/virologia
20.
Blood Cell Ther ; 2(2): 12-21, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37885825

RESUMO

Despite an increase in the development of biological therapies for autoimmune disease (AID), a proportion of patients remain treatment refractory, resulting in long term morbidity and increased rates of mortality. Furthermore, maintenance biologic therapies are associated with treatment-related side effects, significant financial cost,and restricted access, which is of particular relevance in the developing world. Although it carries a significant 'front loaded' cost both financially and regarding adverse events, autologous hematopoietic stem cell transplantation (AHSCT) represents a potential single therapeutic intervention, which in the appropriate patient, condition, and transplant center, may offer sustained disease remission resulting in improved overall survival, disease relapse-free survival, improved quality of life, and decreased financial burden. Emerging Phase II and III trial and registry data, to which our center has been a significant contributor over the past two decades, are providing invaluable evidence as to which AIDs are most likely to receive a sustained benefit from AHSCT and which conditioning regimens are preferable. Similar to trends for the treatment of malignant disease, AHSCT for AID may find a place in both developed and developing countries as nations become more familiar with the transplantation process. If this occurs, benchmarking by key regulatory bodies, collaboration between medical specialties, and the development of experienced 'centers of excellence' will be key to enhance safety and benefit to patients and society at large.

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