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1.
Histopathology ; 82(4): 508-520, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36221864

RESUMO

Squamous cell carcinoma (SCC) is the most common malignant tumour of the penis. The 2022 WHO classification reinforces the 2016 classification and subclassifies precursor lesions and tumours into human papillomavirus (HPV)-associated and HPV-independent types. HPV-associated penile intraepithelial neoplasia (PeIN) is a precursor lesion of invasive HPV- associated SCC, whereas differentiated PeIN is a precursor lesion of HPV-independent SCC. Block-type positivity of p16 immunohistochemistry is the most practical daily utilised method to separate HPVassociated from HPVindependent penile SCC. If this is not feasible, the term SCC, not otherwise specified (NOS) is appropriate. Certain histologies that were previously classified as "subtypes" are now grouped, and coalesced as "patterns", under the rubric of usual type SCC and verrucous carcinoma (e.g. usual-type SCC includes pseudohyperplastic and acantholytic/pseudoglandular carcinoma, and carcinoma cuniculatum is included as a pattern of verrucous carcinoma). If there is an additional component of the usual type of invasive SCC (formerly termed hybrid histology), the tumour would be a mixed carcinoma (e.g. carcinoma cuniculatum or verrucous carcinoma with usual invasive SCC); in such cases, reporting of the relative percentages in mixed tumours may be useful. The consistent use of uniform nomenclature and reporting of percentages will inform the refinement of future reporting classification schemes and guidelines/recommendations. The classification of scrotal tumours is provided for the first time in the fifth edition of the WHO Blue book, and it follows the schema of penile cancer classification for both precursor lesions and the common SCC of the scrotum. Basal cell carcinoma of the scrotum may have a variable clinical course and finds a separate mention.


Assuntos
Carcinoma de Células Escamosas , Carcinoma Verrucoso , Neoplasias dos Genitais Masculinos , Infecções por Papillomavirus , Neoplasias Penianas , Neoplasias Cutâneas , Masculino , Humanos , Infecções por Papillomavirus/patologia , Escroto/metabolismo , Escroto/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Penianas/patologia , Papillomavirus Humano , Organização Mundial da Saúde , Papillomaviridae
2.
Rev Sci Instrum ; 88(8): 083114, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28863625

RESUMO

Resonant Raman spectroscopy requires that the wavelength of the laser used is close to that of an electronic transition. A tunable laser source and a triple spectrometer are usually necessary for resonant Raman profile measurements. However, such a system is complex with low signal throughput, which limits its wide application by scientific community. Here, a tunable micro-Raman spectroscopy system based on the supercontinuum laser, transmission grating, tunable filters, and single-stage spectrometer is introduced to measure the resonant Raman profile. The supercontinuum laser in combination with transmission grating makes a tunable excitation source with a bandwidth of sub-nanometer. Such a system exhibits continuous excitation tunability and high signal throughput. Its good performance and flexible tunability are verified by resonant Raman profile measurement of twisted bilayer graphene, which demonstrates its potential application prospect for resonant Raman spectroscopy.

3.
4.
Rev Sci Instrum ; 87(5): 053122, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27250407

RESUMO

Ultralow-frequency (ULF) Raman spectroscopy becomes increasingly important in the area of two-dimensional (2D) layered materials; however, such measurement usually requires expensive and nonstandard equipment. Here, the measurement of ULF Raman signal down to 10 cm(-1) has been realized with high throughput by combining a kind of longpass edge filters with a single monochromator, which are verified by the Raman spectrum of L-cystine using three laser excitations. Fine adjustment of the angle of incident laser beam from normal of the longpass edge filters and selection of polarization geometry are demonstrated how to probe ULF Raman signal with high signal-to-noise. Davydov splitting of the shear mode in twisted (2+2) layer graphenes (t(2+2)LG) has been observed by such system in both exfoliated and transferred samples. We provide a direct evidence of twist-angle dependent softening of the shear coupling in t(2+2)LG, while the layer-breathing coupling at twisted interfaces is found to be almost identical to that in bulk graphite. This suggests that the exfoliation and transferring techniques are enough good to make a good 2D heterostructures to demonstrate potential device application. This Raman system will be potentially applied to the research field of ULF Raman spectroscopy.

5.
Malays J Pathol ; 38(1): 19-24, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27126660

RESUMO

Taking cognizance of the purported variation of phyllodes tumours in Asians compared with Western populations, this study looked at phyllodes tumours of the breast diagnosed at the Department of Pathology, University of Malaya Medical Centre over an 8-year period with regards to patient profiles, tumour parameters, treatment offered and outcome. Sixty-four new cases of phyllodes tumour were diagnosed during the period, however only 30 (21 benign, 4 borderline and 5 malignant) finally qualified for entry into the study. These were followed-up for 4-102 months (average = 41.7 months). Thirteen cases (8 benign, 3 borderline, 2 malignant) were Chinese, 9 (all benign) Malay, 7 (4 benign, 1 borderline, 2 malignant) Indian and 1 (malignant) Indonesian. Prevalence of benign versus combined borderline and malignant phyllodes showed a marginally significant difference (p=0.049) between the Malays and Chinese. Patients' ages ranged from 21-70 years with a mean of 44.9 years with no significant difference in age between benign, borderline or malignant phyllodes tumours. Except for benign phyllodes tumours (mean size = 5.8 cm) being significantly smaller at presentation compared with borderline (mean size = 12.5 cm) and malignant (mean size = 15.8 cm) (p<0.05) tumours, history of previous pregnancy, breast feeding, hormonal contraception and tumour laterality did not differ between the three categories. Family history of breast cancer was noted in 2 cases of benign phyllodes. Local excision was performed in 17 benign, 2 borderline and 3 malignant tumours and mastectomy in 4 benign, 2 borderline and 2 malignant tumours. Surgical clearance was not properly recorded in 10 benign phyllodes tumours. Six benign and all 4 borderline and 5 malignant tumours had clearances of <10 mm. Two benign tumours recurred locally at 15 and 49 months after local excision, however information regarding surgical clearance was not available in both cases. One patient with a malignant tumour developed a radiologically-diagnosed lung nodule 26 months after mastectomy, was given a course of radiotherapy and remained well 8-months following identification of the lung nodule.


Assuntos
Neoplasias da Mama/patologia , Hospitais Universitários , Tumor Filoide/patologia , Adulto , Idoso , Neoplasias da Mama/etnologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/secundário , Mastectomia , Pessoa de Meia-Idade , Neoplasia Residual , Tumor Filoide/etnologia , Tumor Filoide/radioterapia , Tumor Filoide/secundário , Tumor Filoide/cirurgia , Prevalência , Estudos Retrospectivos , Fatores de Risco , Singapura/epidemiologia , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral , Adulto Jovem
7.
Lupus ; 25(4): 399-406, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26537422

RESUMO

We have previously reported the one-year outcomes of 16 children with severe proliferative lupus nephritis (LN) who were treated using a multi-targeted induction protocol based on intravenous (IV) pulse methylprednisolone (MP), mycophenolate mofetil (MMF) and cyclosporine (CSA). This study examined the long-term renal outcomes of these 16 children, followed up for a median duration of 9.2 years (range 5.8-14.2 years). Primary treatment outcome was complete renal remission. Secondary outcomes included patient and renal survival as well as relapse-free and event-free survival. All patients achieved complete renal remission within 24 months (median 8.7 months, range 4.0-24.0 months). Comparing clinical and laboratory parameters at induction and last follow-up, respectively, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score (25.4 ± 8.7 vs. 0.4 ± 0.8), serum complement C3 (47 ± 21 vs. 107 ± 27 mg/dL), estimated glomerular filtration rate (eGFR) (72 ± 57 vs. 109.7 ± 43 ml/min/1.73 m2) and urine protein (6.97 ± 7.09 vs. 0.2 ± 0.02 g/day/1.73 m2) improved significantly (p < 0.05). Kaplan-Meier survival analysis showed a cumulative ten-year renal relapse-free survival of 73.3% when considering relapses with severe proteinuria >1 g/day/1.73 m2. Cumulative probability that hospitalization would not be required was 93.8% at one year, and 71.4% at ten years. Our multi-targeted protocol for induction and maintenance therapy in Asian children with severe proliferative LN resulted in good long-term patient survival and renal preservation, with a good safety profile.


Assuntos
Ciclosporina/administração & dosagem , Imunossupressores/administração & dosagem , Nefrite Lúpica/tratamento farmacológico , Metilprednisolona/administração & dosagem , Ácido Micofenólico/administração & dosagem , Administração Intravenosa , Adolescente , Fatores Etários , Criança , Pré-Escolar , Intervalo Livre de Doença , Quimioterapia Combinada , Feminino , Seguimentos , Hospitalização , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Nefrite Lúpica/diagnóstico , Nefrite Lúpica/imunologia , Masculino , Pulsoterapia , Recidiva , Indução de Remissão , Fatores de Risco , Índice de Gravidade de Doença , Singapura , Fatores de Tempo , Resultado do Tratamento
8.
Am J Transplant ; 15(12): 3229-38, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26147534

RESUMO

Individuals with TRPC6 mutations have variable phenotypes, ranging from healthy carrier to focal segmental glomerulosclerosis (FSGS) leading to renal failure. Here, we describe a family where six members had a novel TRPC6 p.R68W (c.202C>T) mutation, two of whom had renal failure from FSGS, and one had proteinuria. One healthy carrier donated a kidney to her sister. Both donor and recipient had no proteinuria at 20 years posttransplant. Two synonymous NPHS1 polymorphisms, rs2285450 (c.294C>T) and rs437168 (c.2289C>T) segregated with renal failure in this family. These variants had higher allele frequencies in 97 unrelated patients with nephrotic syndrome or FSGS compared to 224 controls. Using patch-clamp experiments in HEK293 and podocytes, we showed that the p.R68W mutation increased TRPC6 current amplitudes, which may be explained by enhanced TRPC6 surface expression. Additionally, while wild-type nephrin suppressed TRPC6 currents, this ability was lost in the presence of NPHS1 c.294C>T polymorphism. When cells were transfected according to combined TRPC6 and NPHS1 genotypes in the family, those representing the donor had lower TRPC6 currents than cells representing the recipient, suggesting that interactions between TRPC6 and NPHS1 variants could possibly account for the variable penetrance of TRPC6 mutations and the absence of recurrence in the graft.


Assuntos
Glomerulosclerose Segmentar e Focal/etiologia , Transplante de Rim/efeitos adversos , Proteínas de Membrana/genética , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , Canais de Cátion TRPC/genética , Adolescente , Adulto , Idoso , Animais , Western Blotting , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Seguimentos , Frequência do Gene , Genótipo , Taxa de Filtração Glomerular , Glomerulosclerose Segmentar e Focal/patologia , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto , Células HEK293 , Humanos , Lactente , Testes de Função Renal , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Linhagem , Fenótipo , Podócitos , Complicações Pós-Operatórias , Prognóstico , Recidiva , Fatores de Risco , Canal de Cátion TRPC6 , Adulto Jovem
9.
Br J Cancer ; 112(2): 283-9, 2015 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-25422911

RESUMO

BACKGROUND: Metaplastic breast carcinoma (MBC) is a rare type of breast cancer that has basal-like characteristics and is perceived to have poorer prognosis when compared with conventional no specific type/ductal carcinomas (ductal/NST). However, current data on MBC are largely derived from small case series or population-based reports. This study aimed to assess the clinicopathological features and outcome of MBC identified through an international multicentre collaboration. METHODS: A large international multicentre series of MBC (no=405) with histological confirmation and follow-up information has been included in this study. The prognostic value of different variables and outcome has been assessed and compared with grade, nodal status and ER/HER2 receptor-matched ductal/NST breast carcinoma. RESULTS: The outcome of MBC diagnosed in Asian countries was more favourable than those in Western countries. The outcome of MBC is not different from matched ductal/NST carcinoma but the performance of the established prognostic variables in MBC is different. Lymph node stage, lymphovascular invasion and histologic subtype are associated with outcome but tumour size and grade are not. Chemotherapy was associated with longer survival, although this effect was limited to early-stage disease. In this study no association between radiotherapy and outcome was identified. Multivariate analysis of MBC shows that histologic subtype is an independent prognostic feature. CONCLUSIONS: This study suggests that MBC is a heterogeneous disease. Although the outcome of MBC is not different to matched conventional ductal/NST breast carcinoma, its behaviour is dependent on the particular subtype with spindle cell carcinoma in particular has an aggressive biological behaviour. Management of patients with MBC should be based on validated prognostic variables.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/terapia , Feminino , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Resultado do Tratamento
10.
Clin Oncol (R Coll Radiol) ; 26(11): 684-91, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25194727

RESUMO

AIMS: At our centre, ductal carcinoma in situ (DCIS) was commonly treated with breast-conservation therapy (BCT). Local recurrence after BCT is a major concern. The aims of our study were to review the outcomes of DCIS treatment in our patients and to evaluate a nomogram from Memorial Sloan Kettering Cancer Centre (MSKCC) for predicting ipsilateral breast tumour recurrence (IBTR) in our Asian population. MATERIALS AND METHODS: Chart reviews of 716 patients with pure DCIS treated from 1992 to 2011 were carried out. Univariable Cox regression analyses were used to evaluate the effects of the 10 prognostic factors of the MSKCC nomogram on IBTR. We constructed a separate National Cancer Centre Singapore (NCCS) nomogram based on multivariable Cox regression via reduced model selection by applying the stopping rule of Akaike's information criterion to predict IBTR-free survival. The abilities of the NCCS nomogram and the MSKCC nomogram to predict IBTR of individual patients were evaluated with bootstrapping of 200 sets of resamples and the NCCS dataset, respectively. Harrell's c-index was calculated for each nomogram to evaluate the concordance between predicted and observed responses of individual subjects. RESULTS: Study patients were followed up for a median of 70 months. Over 95% of patients received adjuvant radiotherapy. The 5 and 10 year actuarial IBTR-free survival rates for the cohort were 95.5 and 92.6%, respectively. In the multivariate analysis, independent prognostic factors for IBTR included use of adjuvant endocrine therapy, presence of comedonecrosis and younger age at diagnosis. These factors formed the basis of the NCCS nomogram, which had a similar c-index (NCCS: 0.696; MSKCC: 0.673) compared with the MSKCC nomogram. CONCLUSION: The MSKCC nomogram was validated in an Asian population. A simpler NCCS nomogram using a different combination of fewer prognostic factors may be sufficient for the prediction of IBTR in Asians, but requires external validation to compare for relative performance.


Assuntos
Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/cirurgia , Mastectomia Segmentar , Recidiva Local de Neoplasia/diagnóstico , Nomogramas , Ásia/epidemiologia , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Feminino , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Estudos Retrospectivos
11.
Phys Rev Lett ; 112(4): 047401, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24580489

RESUMO

In monolayer MoS2, optical transitions across the direct band gap are governed by chiral selection rules, allowing optical valley initialization. In time-resolved photoluminescence (PL) experiments, we find that both the polarization and emission dynamics do not change from 4 to 300 K within our time resolution. We measure a high polarization and show that under pulsed excitation the emission polarization significantly decreases with increasing laser power. We find a fast exciton emission decay time on the order of 4 ps. The absence of a clear PL polarization decay within our time resolution suggests that the initially injected polarization dominates the steady-state PL polarization. The observed decrease of the initial polarization with increasing pump photon energy hints at a possible ultrafast intervalley relaxation beyond the experimental ps time resolution. By compensating the temperature-induced change in band gap energy with the excitation laser energy, an emission polarization of 40% is recovered at 300 K, close to the maximum emission polarization for this sample at 4 K.

12.
Br J Cancer ; 109(1): 109-13, 2013 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-23787917

RESUMO

BACKGROUND: Tumours arising in younger women appear to be biologically more aggressive and tend to have a poorer outcome. Being relatively resistant to conventional treatments, breast cancer stem cells (CSCs) have been postulated as a possible cause of disease recurrence after treatment. In this study, we used ALDH1 as a CSC marker and determined whether ALDH1 expression correlated with clinical outcome in young women with breast cancer. METHODS: The expression of ALDH1 was evaluated through immunohistochemistry on microarrayed cores obtained from 141 consecutive patients up to 35 years of age. RESULTS: The expression of ALDH1 was observed in 25% (35 of 141) of tumours, in a median of 5% of cells. Younger women were 14 times more likely to have ALDH1-positive tumours (P<0.01, OR 14.4, 95% CI 4.34-48.09). The ALDH1 correlated independently with ER negativity (P=0.01, OR 0.33, 95% CI 0.15-0.77). There was no correlation with disease recurrence or breast cancer-related deaths. CONCLUSION: In younger women, ALDH1 was more highly expressed, and it correlated with ER negativity. It, however, did not predict survival in this study.


Assuntos
Neoplasias da Mama/enzimologia , Isoenzimas/metabolismo , Receptores de Estrogênio/metabolismo , Retinal Desidrogenase/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Família Aldeído Desidrogenase 1 , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/mortalidade , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Células-Tronco Neoplásicas/metabolismo , Resultado do Tratamento , Adulto Jovem
13.
Breast Cancer Res Treat ; 136(1): 209-20, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22965832

RESUMO

Genome-wide association studies (GWAS) have identified various genetic susceptibility loci for breast cancer based mainly on European-ancestry populations. Differing linkage disequilibrium patterns exist between European and Asian populations, and thus GWAS-identified single nucleotide polymorphisms (SNPs) in one population may not be of significance in another population. In order to explore the role of breast cancer susceptibility variants in a Chinese population of Southern Chinese descent, we analyzed 22 SNPs for 1,191 breast cancer cases and 1,534 female controls. Associations between the SNPs and clinicopathological features were also investigated. In addition, we evaluated the combined effects of associated SNPs by constructing risk models. Eight SNPs were associated with an elevated breast cancer risk. Rs2046210/6q25.1 increased breast cancer risk via an additive model [per-allele odds ratio (OR) = 1.43, 95 % confidence interval (CI) = 1.26-1.62], and was associated with estrogen receptor (ER)-positive (per-allele OR = 1.39, 95 % CI = 1.20-1.61) and ER-negative (per-allele OR = 1.55, 95 % CI = 1.28-1.89) disease. Rs2046210 was also associated with stage 1, stage 2, and stage 3 disease, with per-allele ORs of 1.38 (1.14-1.68), 1.48 (1.25-1.74), and 1.58 (1.28-1.94), respectively. Four SNPs mapped to 10q26.13/FGFR2 were associated with increased breast cancer risk via an additive model with per-allelic risks (95 % CI) of 1.26 (1.12-1.43) at rs1219648, 1.22 (1.07-1.38) at rs2981582, 1.21 (1.07-1.36) at rs2981579, and 1.18 (1.04-1.35) at rs11200014. Variants of rs7696175/TLR1, TLR6, rs13281615/8q24, and rs16886165/MAP3K1 were also associated with increased breast cancer risk, with per-allele ORs (95 % CI) of 1.16 (1.00-1.34), 1.15 (1.02-1.29), and 1.15 (1.01-1.29), respectively. Five SNPs associated with breast cancer risk predominantly among ER-positive tumors (rs2981582/FGFR2, rs4415084/MRPS30, rs1219648/FGFR2, rs2981579/FGFR2, and rs11200014/FGFR2). Among our Chinese population, the risk of developing breast cancer increased by 90 % for those with a combination of 6 or more risk alleles, compared to patients with ≤3 risk alleles.


Assuntos
Neoplasias da Mama , Estudos de Associação Genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , China , Feminino , Loci Gênicos , Predisposição Genética para Doença , Humanos , Desequilíbrio de Ligação , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Fatores de Risco
14.
Anaesthesia ; 67(11): 1225-31, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22823006

RESUMO

We examined the pre-emptive analgesic effect of a cyclooxygenase (COX)-2 inhibitor in a rat surgical pain model and characterised the changes in cutaneous COX-2 around a surgical site. Thermal hyperalgesia and mechanical allodynia were tested in the rats for three days after incision and skin tissues were collected for analysis of COX-2. There was decreased expression of cutaneous COX-2 one day after surgical incision. Pre-incision injection of the COX-2 inhibitor significantly inhibited expression of COX-2 and also reduced thermal hyperalgesia (but not mechanical allodynia) compared with the post-incision COX-2-inhibitor injection group, one day after incision.


Assuntos
Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Manejo da Dor/métodos , Dor Pós-Operatória/prevenção & controle , Pirazóis/uso terapêutico , Sulfonamidas/uso terapêutico , Doença Aguda , Análise de Variância , Animais , Comportamento Animal , Western Blotting , Ciclo-Oxigenase 2/biossíntese , Temperatura Alta , Hiperalgesia/prevenção & controle , Masculino , Medição da Dor/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , Estimulação Física , Ratos , Ratos Sprague-Dawley
15.
Nat Mater ; 11(4): 294-300, 2012 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-22306771

RESUMO

The quest for materials capable of realizing the next generation of electronic and photonic devices continues to fuel research on the electronic, optical and vibrational properties of graphene. Few-layer graphene (FLG) flakes with less than ten layers each show a distinctive band structure. Thus, there is an increasing interest in the physics and applications of FLGs. Raman spectroscopy is one of the most useful and versatile tools to probe graphene samples. Here, we uncover the interlayer shear mode of FLGs, ranging from bilayer graphene (BLG) to bulk graphite, and suggest that the corresponding Raman peak measures the interlayer coupling. This peak scales from ~43 cm(-1) in bulk graphite to ~31 cm(-1) in BLG. Its low energy makes it sensitive to near-Dirac point quasiparticles. Similar shear modes are expected in all layered materials, providing a direct probe of interlayer interactions.

16.
Br J Anaesth ; 108(4): 662-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22307241

RESUMO

BACKGROUND: There is increasing interest in RNA interference in pain research using the intrathecal route to deliver small-interfering RNA (siRNA). An interferon (IFN) response is a common side-effect of siRNA. However, the IFN response in the spinal cord after intrathecal administration of siRNA remains unknown. We hypothesized that high doses of siRNAs can elicit off-target analgesia via releasing IFN-α. We investigated the IFN response and its role in regulating pain sensitivity in the spinal cords after intrathecal administration of siRNAs. METHODS: Male Sprague-Dawley rats were given intrathecal injections of non-targeting (NT) siRNAs or IFN-α and tested for complete Freund's adjuvant (CFA)-induced mechanical allodynia and heat hyperalgesia. IFN-α in the spinal cord after injection of NT siRNAs was measured by western blotting and immunohistochemical staining. RESULTS: IFN-α was up-regulated in the spinal cord after intrathecal treatment of NT siRNAs. Intrathecal injection of NT siRNAs, at high doses of 10 or 20 µg, reduced CFA-induced inflammatory pain (P<0.05). Intrathecal application of IFN-α inhibited pain hypersensitivity in inflamed rats and produced analgesia in naïve rats (P<0.05). Notably, the anti-nociceptive effects elicited by NT siRNAs and IFN-α were reversed by IFN-α neutralizing antibody and naloxone. CONCLUSIONS: Our data suggest that (i) intrathecal administration of high doses of siRNA (≥ 10 µg) induced up-regulation of IFN-α in the spinal cord and produced analgesic effects through IFN-α, and (ii) IFN-α's analgesic effect is mediated via opioid receptors. Caution must be taken to avoid IFN-α-mediated analgesic effects of siRNAs in pain research.


Assuntos
Analgesia/métodos , Interferon-alfa/farmacologia , Dor/tratamento farmacológico , RNA Interferente Pequeno/farmacologia , Animais , Western Blotting , Modelos Animais de Doenças , Adjuvante de Freund/administração & dosagem , Adjuvante de Freund/farmacologia , Hiperalgesia/tratamento farmacológico , Fatores Imunológicos/farmacologia , Inflamação/complicações , Inflamação/tratamento farmacológico , Injeções Espinhais , Interferon-alfa/administração & dosagem , Masculino , Dor/complicações , Manejo da Dor/métodos , Limiar da Dor/efeitos dos fármacos , RNA Interferente Pequeno/administração & dosagem , Ratos , Ratos Sprague-Dawley , Medula Espinal/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
17.
Diabetologia ; 55(4): 1091-102, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22270222

RESUMO

AIMS/HYPOTHESIS: Limited information is available on the cellular interactions between regulatory T (T(reg)) cells and mesenchymal stem cells (MSCs). In particular, a direct effect of MSCs on the survival and proliferation of T(reg) cells has not been demonstrated. METHODS: We investigated the effects of MSCs on effector T (T(eff)) cells and T(reg) cells, and the molecular mechanisms involved in the distinct regulation of these two cell populations by MSCs in vivo and in vitro. RESULTS: We show that MSCs are capable of selectively suppressing T(eff) cells and fostering the generation of T(reg) cells. T(eff) cells, but not T(reg) cells, fail to respond to IL-2 and undergo profound apoptosis in the presence of MSCs. The differential regulations of these two T cell subsets by MSCs are associated with their distinct expressions of CD25, with MSCs specifically reducing the expression of CD25 on T(eff) and sparing T(reg) cells intact. In vivo, the administration of MSCs significantly delays the rejection of allogeneic islet grafts in adaptive transferred recipients by favouring the induction of T(reg) cells. In this model, MSCs inhibit the proliferation and development of alloreactive T(eff) but potently enhance the induction of T(reg) cells. CONCLUSIONS/INTERPRETATION: We demonstrate that MSCs are capable of regulating T(eff) and T(reg) cells differentially in vitro. MSCs inhibit T(eff) cells by inducing apoptosis and impairing the proliferative response to IL-2 in T(eff) cells, but favour the survival and expansion of T(reg) cells. This result is further demonstrated in mice that have undergone allogeneic islet transplantation, in which MSCs suppress alloreactive T(eff) cells while favouring the induction of T(reg) cells, thus protecting the islet allografts from rejection.


Assuntos
Diabetes Mellitus Experimental/cirurgia , Sobrevivência de Enxerto/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Células-Tronco Mesenquimais/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Animais , Proliferação de Células , Diabetes Mellitus Experimental/imunologia , Camundongos
18.
Ann Oncol ; 23(4): 1010-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21768327

RESUMO

BACKGROUND: Gefitinib was demonstrated to be synergistic with cisplatin and radiotherapy (RT) in in vitro studies. Biomarkers predictive of response to gefitinib in squamous cell head and neck cancer is still lacking. METHODS: Thirty-one patients with locally advanced and easily accessible primary tumor sites for biopsies were recruited. Gefitinib was started 3 weeks before the start of cisplatin/concurrent radiotherapy (CTRT) and continued during the CTRT phase and thereafter for 4 months as consolidation phase. Two baselines and a repeat tumor sample were taken after 2 weeks of gefitinib alone to study its impact on tumor gene expression. Epidermal growth factor receptor (EGFR) protein expression, FISH and mutational status, and matrix metallopeptidase 11 (MMP11) protein expression were correlated with response and survival outcome. RESULTS: The overall response rate to gefitinib alone was 9.7%. The survival outcome is as follows: median disease free 1.3 years, median survival time 2.4 years, 3-year disease free 42.9%, and 3-year overall survival 48.4%. EGFR FISH, protein expression, and mutational status did not predict for response nor survival outcome of patients. Although MMP11 overexpression did not predict for response, it predicted significantly for a poorer survival outcome. CONCLUSIONS: Gefitinib can be combined safely with cisplatin/RT. More studies are needed to uncover predictive biomarkers of benefit to gefitinib.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Quimiorradioterapia , Receptores ErbB/metabolismo , Neoplasias de Cabeça e Pescoço/terapia , Adulto , Idoso , Biomarcadores Tumorais/genética , Cisplatino/administração & dosagem , Análise Mutacional de DNA , Intervalo Livre de Doença , Receptores ErbB/genética , Feminino , Gefitinibe , Expressão Gênica , Perfilação da Expressão Gênica , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Hibridização in Situ Fluorescente , Masculino , Metaloproteinase 11 da Matriz/genética , Metaloproteinase 11 da Matriz/metabolismo , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Quinazolinas/administração & dosagem , Fatores de Risco , Fumar , Resultado do Tratamento
19.
Eur J Cancer Care (Engl) ; 20(6): 703-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21883568

RESUMO

Breast cancer management is an important part of the health-care system. In the current harsh economic climate, these costs have to be controlled, and achieving this without compromising quality of care is a daunting challenge. This article discusses the need to find effective and well-targeted chemotherapeutic regimens, which, when combined with appropriate implementation of novel strategies, will provide the optimum treatment for patients while maintaining economic viability.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/economia , Neoplasias da Mama/tratamento farmacológico , Custos de Cuidados de Saúde , Neoplasias da Mama/economia , Feminino , Humanos , Medicina Estatal/economia , Reino Unido
20.
Anaesthesia ; 66(9): 791-5, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21707563

RESUMO

Increased tracheal cuff pressure during mechanical ventilation is associated with reduced mucosal blood flow and ischaemia, as well as postoperative sore throat. We assessed the potential effects of transoesophageal echocardiography probe insertion on the tracheal cuff pressure in patients undergoing cardiac surgery. Using a manometer, the cuff pressure of a high-volume, low-pressure tracheal tube (inner diameter 7.0 mm for women and 7.5 mm for men) was adjusted to 25-30 cm H(2)O before blind insertion of a transoesophageal echocardiography probe. The pressure changes were then recorded for 1 min. After probe insertion, the mean (SD) intra-cuff pressure increased from 27.7 (1.5) to 36.2 (6.4) cm H(2)O (p < 0.001) and was > 35 cm H(2)0 in 17/38 patients (45%). Our results suggest that transoesophageal echocardiography probe insertion may increase the tracheal cuff pressure more than that is generally recommended and therefore the latter should be routinely monitored under such circumstances.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Ecocardiografia Transesofagiana/efeitos adversos , Intubação Intratraqueal/instrumentação , Adulto , Idoso , Ecocardiografia Transesofagiana/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão , Traqueia/irrigação sanguínea
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