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2.
J Pediatr Adolesc Gynecol ; 34(5): 662-665, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33989805

RESUMO

STUDY OBJECTIVE: Adolescent menstrual dysfunction (AMD) is a common cause of iron deficiency anemia and absences from school. The management of AMD with single- and double-dose desogestrel is largely on the basis of anecdotal evidence. Our aim was to describe the effectiveness and safety of both dosing strategies in our clinic cohort to help guide future management. DESIGN: Local service evaluation with retrospective analysis of clinic notes. SETTING: Adolescent gynecology clinic in a tertiary pediatric center in the North West of England. PARTICIPANTS: Adolescent girls (10-18 years of age) with AMD (n = 129). INTERVENTIONS: Single-dose (75 µg) desogestrel vs double-dose (150 µg) desogestrel. MAIN OUTCOME MEASURES: Prevalence of amenorrhea and light spotting, side effects, and discontinuation rates of both dosing regimens. RESULTS: Forty-three of 87 (49%) adolescent girls who started treatment with a double dose of desogestrel were amenorrheic/experienced light spotting, compared with 7/40 (18%) of girls who started treatment with a single dose (P = .001). Patients taking a double dose of desogestrel were less likely to discontinue overall (double: 45/89 [51%]; vs single: 35/40 [88%]; P < .001) and there was no evidence of an increase in nonbleeding side effects (double: 30/89 [34%]; vs single: 15/40 [38%]; P = .68). CONCLUSION: Our findings provide evidence that a double dose of desogestrel is associated with a higher prevalence of amenorrhea and light spotting compared with a single dose in adolescent girls with AMD. However, larger studies are needed to further inform clinical guidelines.


Assuntos
Desogestrel , Metrorragia , Adolescente , Amenorreia/induzido quimicamente , Criança , Desogestrel/efeitos adversos , Etinilestradiol , Feminino , Humanos , Estudos Retrospectivos
3.
Scand J Immunol ; 73(2): 85-90, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21198748

RESUMO

We have previously reported a new receptor (NC-2) for natural cytotoxicity (NC) on murine leucocytes, identified by monoclonal antibody D9 (mAb D9). Pretreatment of mouse spleen cells with different concentrations of mAb D9 in vitro blocked NC against WEHI-164, whereas natural killing (NK) activity against YAC-1 was unaffected. This paper reports the immune surveillance against the growth of WEHI-164 tumour cells in mice by NC-2(+) Cells. The kinetics of in vivo reduction in NC activity were investigated by treating BALB/c and (CBA × C57BL/6) F1 mice with a single injection of 40 µg of mAb D9 and monitoring splenic NC activity by (51) Cr-release assay at intervals from 24 h to 3 weeks. Control mice were injected with OKT8 irrelevant antibody. Results showed a significant (P < 0.05) reduction in splenic NC activity within 24 h which persisted for up to 1 week. Similar results were also obtained when (CBA × C57BL/6) F1 mice were employed (P<0.001). In vivo tumour studies were undertaken to investigate the role of NC-2(+) cells in surveillance against tumour growth and metastasis of the WEHI-164 fibrosarcoma. When syngeneic BALB/c mice were injected with 40 µg of mAb D9 and then challenged with 5 × 10(5) WEHI-164 cells, results showed significantly increased growth rate of the transplanted WEHI-164 fibrosarcoma and tumour nodules in the lungs of animals, when compared to control mice with normal NC activity. Our data support an innate surveillance in metastasis and growth of WEHI-164 fibrosarcoma in mice.


Assuntos
Fibrossarcoma/patologia , Neoplasias Pulmonares/secundário , Animais , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Masculino , Camundongos , Transplante de Neoplasias
4.
J Phys Chem B ; 114(26): 8807-16, 2010 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-20550207

RESUMO

In this contribution, neutron scattering experiments (with isotopic substitution) of concentrated and supersaturated methanolic benzoic acid solutions combined with empirical potential structure refinement (EPSR) were used to investigate the time-averaged atomistic details of this system. Through the determination of radial distribution functions, quantitative details emerge of the solution coordination, its relationship to the nature of the crystalline phase, and the response of the solution to imposed supersaturation.

5.
Br J Dermatol ; 161(6): 1270-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19747359

RESUMO

BACKGROUND: Studies have shown the benign to malignant ratio of excised pigmented skin lesions is suboptimal in primary care. OBJECTIVES: To assess the impact of dermoscopy and short-term sequential digital dermoscopy imaging (SDDI) on the management of suspicious pigmented skin lesions by primary care physicians. METHODS: A total of 63 primary care physicians were trained in the use of dermoscopy and SDDI (interventions) and then recruited pigmented lesions requiring biopsy or referral in routine care by naked eye examination. They were then given a dermatoscope and the option of a SDDI instrument, and change of diagnosis and management was assessed. RESULTS: Following the use of the interventions on 374 lesions a total of 163 lesions (43.6%) were excised or referred, representing a reduction of 56.4%. Of the 323 lesions confirmed to be benign, 118 (36.5%) were excised or referred, leading to a reduction of 63.5% (P < 0.0005) in those requiring excision or referral. The baseline naked eye examination benign to melanoma ratio was 9.5 : 1 which decreased to 3.5 : 1 after the diagnostic interventions (P < 0.0005). Of the 42 malignant lesions included in the study (34 melanoma, six pigmented basal cell carcinoma and two Bowen disease) only one in situ melanoma was incorrectly managed (patient to return if changes occur) resulting in the correct management of 97.6% and 97.1% of malignant pigmented lesions and melanoma, respectively. CONCLUSIONS: In a primary care setting the combination of dermoscopy and short-term SDDI reduces the excision or referral of benign pigmented lesions by more than half while nearly doubling the sensitivity for the diagnosis of melanoma.


Assuntos
Dermoscopia/métodos , Detecção Precoce de Câncer/métodos , Melanoma/diagnóstico , Exame Físico/métodos , Neoplasias Cutâneas/diagnóstico , Competência Clínica , Medicina de Família e Comunidade/educação , Medicina de Família e Comunidade/estatística & dados numéricos , Feminino , Humanos , Masculino , Melanoma/cirurgia , Mucosa , Variações Dependentes do Observador , Encaminhamento e Consulta/estatística & dados numéricos , Sensibilidade e Especificidade , Neoplasias Cutâneas/cirurgia , Austrália Ocidental
6.
J Phys Chem B ; 113(17): 5967-77, 2009 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-19351125

RESUMO

The water-hexamethylenetetramine system displays features of significant interest in the context of phase equilibria in molecular materials. First, it is possible to crystallize two solid phases depending on temperature, both hexahydrate and anhydrous forms. Second, saturated aqueous solutions in equilibrium with these forms exhibit a negative dependence of solubility (retrograde) on temperature. In this contribution, neutron scattering experiments (with isotopic substitution) of concentrated aqueous hexamethylenetetramine solutions combined with empirical potential structure refinement (EPSR) were used to investigate the time-averaged atomistic details of this system. Through the derivation of radial distribution functions, quantitative details emerge of the solution coordination, its relationship to the nature of the solid phases, and of the underlying cause of the solubility behavior of this molecule.


Assuntos
Metenamina/química , Nêutrons , Espalhamento de Radiação , Estrutura Molecular , Transição de Fase , Solubilidade , Soluções , Propriedades de Superfície , Temperatura , Água/química
7.
J Comput Chem ; 27(11): 1211-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16755646

RESUMO

Standard molecular dynamics simulations have been carried out on pure alcohols and alcohol/water mixtures. A simple atom-atom force field consisting of Lennard-Jones potentials plus coulombic terms over atomic point charges, but without explicit polarization terms, has been specifically fitted to reproduce several experimental properties of the pure alcohols, and has been used for mixtures by developing combination rules with the TIP3P water model. Densities, enthalpies of vaporization, radial distribution functions, self-diffusion coefficients, and rotational correlation functions of the pure alcohols are well reproduced and compare favorably with those from more sophisticated force fields. Some key aspects of the phase behaviour are correctly reproduced by the molecular dynamics simulation, showing a distinct demixing process for the n-butanol/water mixture as opposed to the stability of the t-butanol/water mixtures. The results demonstrate the ability of a molecular dynamics simulation, even in its standard form and with easily accessible time ranges, but with a carefully optimized force field, to simulate and, to a certain extent, predict the properties of binary mixtures.

11.
J Med Screen ; 5(3): 156-61, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9795877

RESUMO

OBJECTIVE: To measure the performance of trained and untrained general practitioners (GPs) in screening men and women aged 50 or more for melanomas. METHODS: GPs trained in melanoma diagnosis, untrained GPs, and skin cancer specialists examined groups of volunteers, each of which included a small number of subjects with prediagnosed suspicious pigmented lesions (SPLs) that were subsequently excised for histopathological examination. RESULTS: Trained and untrained GPs achieved mean sensitivities of 0.73 and 0.71, and mean predictive values of 0.40 and 0.37, respectively, for the detection of prediagnosed SPLs. When the SPLs had been excised and examined histopathologically, reanalysis showed mean sensitivities of 0.98 and 0.95, mean specificities of 0.52 and 0.49, and mean positive predictive values of 0.24 and 0.22 for the detection of subjects with melanomas by trained and untrained GPs respectively. Trained GPs were significantly better than untrained GPs at diagnosing as melanomas SPLs that subsequently proved to be melanomas (p = 0.04). CONCLUSIONS: GPs in this study achieved high sensitivities in screening older Australian men and women for melanomas, but at the cost of low specificities and positive predictive values. Training in melanoma diagnosis had no significant effect on sensitivity, specificity, and positive predictive value for screening. Data from the study were tested in a model of population screening for melanomas, and costs per life year saved for men aged 50-70 ranged from $A11,852 to $A40,259 depending upon the screening interval and whether the GPs excised the SPLs diagnosed, or referred all patients to skin cancer specialists; this would be as cost effective as cervical cancer screening.


Assuntos
Programas de Rastreamento , Melanoma/diagnóstico , Médicos de Família/educação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pele/patologia
13.
Immunology ; 93(1): 122-8, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9536128

RESUMO

We have previously reported the identification by the murine monoclonal antibody (mAb) 1C4 of the first leucocyte receptor which is involved in natural cytotoxicity (NC) against WEHI-164; the NC-1.1 receptor. We report herein the identification and characterization of a second leucocyte receptor which is involved in NC, NC-2 (MW 50,000), identified by a rat anti-mouse mAb D9 (immunoglobulin G2a; IgG2a). Flow cytometric analysis showed that NC-2 was expressed on < 6% of splenic leucocytes of different inbred mouse strains and 96% of the cells of a mast-cell line which has high NC activity. In vitro treatment of splenic leucocytes with the D9 mAb blocked effector cell-WEHI-164 target cell conjugation and NC by approximately 50% without affecting natural killing (NK). Western blot analysis of affinity purified NC-2 and NC-1.1 using the D9 and 1C4 mAbs showed specific reactivity of the proteins with D9 and 1C4, respectively. Pretreatment of splenic leucocytes with both mAbs blocked NC 84%, a result which almost doubled that caused by either mAb alone. Flow cytometric screening of 16 different mouse cell lines showed that 19% of the cell lines expressed both receptors, 6% expressed only NC-2, 44% expressed mainly or only NC-1.1 and the remaining cells expressed neither receptor. These data indicate that D9 identifies a xeno-antigen, NC-2, which is expressed on cells mediating NC and not NK, and that it is not the previously described NC-1.1 allo-antigen. We conclude that NC-2 is likely to be one of a number of receptor molecules on cells mediating NC against tumour cells.


Assuntos
Citotoxicidade Imunológica/imunologia , Leucócitos/imunologia , Receptores de Superfície Celular/análise , Animais , Anticorpos Monoclonais , Separação Celular , Feminino , Citometria de Fluxo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Receptores de Superfície Celular/imunologia , Baço/imunologia , Células Tumorais Cultivadas
16.
Cancer Immunol Immunother ; 45(2): 115-8, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9390203

RESUMO

Murine natural cytotoxicity, which is a major component of the innate immune response in cancer, is mediated by leukocytes that express the NC-1.1 receptor. Mice depleted of natural cytotoxicity by treatment with an anti-NC-1.1 mAb show enhanced growth of certain transplantable tumors, so agents that enhance natural cytotoxicity by NC-1.1+ cells have the potential to be effective anticancer therapeutic agents. We have examined the immunomodulatory effect of levamisole on natural cytotoxicity mediated by NC-1.1+ cells against the BALB/c WEHI-164 murine fibrosarcoma. Administration of levamisole to BALB/c mice significantly enhanced in vitro splenic natural cytotoxicity against 51Cr-labeled WEHI-164 tumor cells. The effect was most marked 48 h after levamisole treatment, at a dose of 10 mg/kg body weight. This enhancement of natural cytotoxicity by levamisole could be completely abrogated by pretreatment of mice with an anti-NC-1.1 mAb. Treatment of BALB/c mice with 10 mg/kg levamisole significantly reduced the growth of WEHI-164 and this effect was abrogated by pretreatment of mice with anti-NC-1.1, indicating that the antitumor effect of levamisole was mediated, at least in part, via NC-1.1+ cells.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Citotoxicidade Imunológica/efeitos dos fármacos , Levamisol/uso terapêutico , Neoplasias Experimentais/tratamento farmacológico , Proteínas/análise , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/imunologia
17.
Med J Aust ; 167(4): 180-1, 1997 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-9293259
18.
Cytokine ; 9(4): 254-62, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9112334

RESUMO

Using a mAb to NC-1.1, a receptor involved in recognition of tumour targets, the authors have examined the dogma that murine natural cytotoxicity (NC) is exclusively mediated by TNF-alpha. Three different NC-1.1+ spleen cells, WEHI-3BR1 myelomonocytic cells and an uncloned mast cell line-MCL) were reacted with NC-sensitive WEHI-164 targets in vitro, and the induction of TNF-alpha mRNA, surface expression of TNF-alpha, and the appearance of apoptotic bodies in the culture were simultaneously measured. NC-1.1+ spleen cells and WEHI-3BR1 cells showed marked induction of TNF-alpha mRNA within 30 min and this was maintained for up to 18 h. Only transient TNF-alpha mRNA induction was observed in MCL cells at 30 min. Surface TNF-alpha was detected on WEHI-3BR1 cells by 4 h, but was not detected on MCL cells. All three effector cell types mediated NC against WEHI-164 targets within 18 h, but they responded differently to the addition of anti-TNF-alpha mAb: anti-TNF-alpha completely blocked WEHI-3BR1 NC, blocked NC-1.1+ spleen cell NC by approximately 70%, and did not block NC by MCL cells. This indicates that TNF-alpha is induced during NC by WEHI-3BR1 effectors and NC-1.1+ spleen cells, is the sole mediator of NC by WEHI-3BR1, and appears to play no role in NC by MCL cells.


Assuntos
Citotoxicidade Imunológica/imunologia , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Apoptose/imunologia , Linhagem Celular , Testes Imunológicos de Citotoxicidade , Feminino , Citometria de Fluxo , Imunidade Inata , Cinética , Masculino , Mastócitos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Baço/citologia , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/biossíntese
19.
J Immunol ; 158(5): 2035-41, 1997 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9036946

RESUMO

Natural cytotoxicity (NC) against cancer involves receptor-ligand interactions between lymphohemopoietic cells that mediate NC against tumor cells. The only candidate for a receptor on cells mediating NC is NC-1.1, identified using mAb 1C4. In this study we showed that mAb 1C4 blocked NC-1.1+ cell conjugation to WEHI-164 tumor cells, indicating that NC-1.1 is a surface protein required for cell-cell interaction. Affinity-purified NC-1.1 was a 45-kDa monomeric protein. It was a good in vitro substrate for cyclic GMP (cGMP)-dependent protein kinase (PKG) and protein kinase C (PKC) and a relatively poor substrate for cAMP-dependent protein kinase (PKA). Phosphopeptide mapping revealed one phosphopeptide phosphorylated by PKG and PKA, and two additional peptides phosphorylated by PKC. Phosphorylation by PKG or PKA abolished phosphorylation at the PKC sites, while coincubation of NC-1.1 with both PKG and PKC reduced phosphorylation of all sites. NC-1.1 was also a phosphoprotein after immunoprecipitation from intact spleen cells and its phosphorylation was increased after cell stimulation with PKC or PKG activators (phorbol esters or 8-bromo-cGMP). The possible consequences of intracellular signaling were tested in functional assays for NC. Phorbol ester activation of spleen cells increased NC, while 8-bromo-cGMP and 8-bromo-cAMP had little effect. However, coincubation with both phorbol ester and either 8-bromo-cGMP or 8-bromo-cAMP virtually abolished NC without affecting cell conjugation. These results suggest that NC-1.1 is a receptor for a ligand on certain tumor cells and reveal that key intracellular signaling pathways involving PKC, PKG, and PKA interact to effect a coordinated control of NC.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/farmacologia , Citotoxicidade Imunológica/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Proteína Quinase C/farmacologia , Receptores Imunológicos/metabolismo , Animais , Anticorpos Bloqueadores/farmacologia , Anticorpos Monoclonais/farmacologia , Apoptose/imunologia , Testes Imunológicos de Citotoxicidade , Feminino , Células Matadoras Naturais/enzimologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Fosforilação/efeitos dos fármacos , Receptores Imunológicos/efeitos dos fármacos , Receptores Imunológicos/isolamento & purificação
20.
Int J Cancer ; 70(4): 450-60, 1997 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-9033654

RESUMO

Ly-6C+ cells constitute 13 +/- 3% of freshly isolated (CBA x C57BL/6)F1 mouse spleen leukocytes. Three distinct populations were identified: CD3 epsilon +NK-1.1- conventional T cells (6%), CD3 epsilon -NK-1.1- granulocytes (5%) and CD3 epsilon +NK-1.1+ T cells (approximately 2%). The CD3 epsilon +NK-1.1+ cells displayed a predominantly large granular leukocyte morphology and were the only Ly-6C+ cell subset identified by MAb 2B6-F2 to spontaneously lyse the NK-sensitive YAC-1 tumour in vitro. On further phenotypic analysis, these cells co-expressed high levels of TCRV beta 8.1/8.2 and CD11b, moderate levels of CD90 and low levels of CD4 or CD8. The removal of CD4+ and CD8+ cells prior to Ly-6C+ cell sorting showed that it was the CD4-CD8- double-negative (DN) CD3 epsilon +NK-1.1+ T-cell subset which was responsible for killing YAC-1. These results indicate that we have identified a DN Ly-6C+ subset of the recently designated NK-1.1+TCR alpha beta low natural T (NT) cells, which are capable of natural cell-mediated cytotoxicity (NCMC) against the NK-sensitive YAC-I tumour in vitro. Additionally, these cells mediated the in vitro killing of 2 further NK-sensitive tumours, murine B16 melanoma and human Jurkat T lymphoma. YAC-1 and Jurkat expressed Fas and were susceptible to anti-Fas MAb or rhuman Fas ligand (rhFasL)-induced lysis. Furthermore, anti-human Fas MAb M3 was shown to block sorted Ly-6C+ splenocyte in vitro killing of Jurkat. In contrast, B16 did not express cell-surface Fas and was resistant to anti-Fas MAb-induced lysis. Taken together, these results show that not only do Ly-6C+ NT cells kill NK-sensitive tumours in vitro but they mediate this activity via multiple cytotoxic mechanisms including Fas.


Assuntos
Antígenos Ly/imunologia , Imunidade Celular/imunologia , Células Matadoras Naturais/imunologia , Baço/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Feminino , Citometria de Fluxo , Humanos , Células Matadoras Naturais/citologia , Células Matadoras Naturais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Fenótipo , Baço/citologia , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/metabolismo , Células Tumorais Cultivadas/imunologia
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