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1.
Nature ; 629(8010): 105-113, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38632407

RESUMO

Arctic and alpine tundra ecosystems are large reservoirs of organic carbon1,2. Climate warming may stimulate ecosystem respiration and release carbon into the atmosphere3,4. The magnitude and persistency of this stimulation and the environmental mechanisms that drive its variation remain uncertain5-7. This hampers the accuracy of global land carbon-climate feedback projections7,8. Here we synthesize 136 datasets from 56 open-top chamber in situ warming experiments located at 28 arctic and alpine tundra sites which have been running for less than 1 year up to 25 years. We show that a mean rise of 1.4 °C [confidence interval (CI) 0.9-2.0 °C] in air and 0.4 °C [CI 0.2-0.7 °C] in soil temperature results in an increase in growing season ecosystem respiration by 30% [CI 22-38%] (n = 136). Our findings indicate that the stimulation of ecosystem respiration was due to increases in both plant-related and microbial respiration (n = 9) and continued for at least 25 years (n = 136). The magnitude of the warming effects on respiration was driven by variation in warming-induced changes in local soil conditions, that is, changes in total nitrogen concentration and pH and by context-dependent spatial variation in these conditions, in particular total nitrogen concentration and the carbon:nitrogen ratio. Tundra sites with stronger nitrogen limitations and sites in which warming had stimulated plant and microbial nutrient turnover seemed particularly sensitive in their respiration response to warming. The results highlight the importance of local soil conditions and warming-induced changes therein for future climatic impacts on respiration.


Assuntos
Respiração Celular , Ecossistema , Aquecimento Global , Tundra , Regiões Árticas , Carbono/metabolismo , Carbono/análise , Ciclo do Carbono , Conjuntos de Dados como Assunto , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Nitrogênio/análise , Plantas/metabolismo , Estações do Ano , Solo/química , Microbiologia do Solo , Temperatura , Fatores de Tempo
2.
BMC Geriatr ; 20(1): 347, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32928151

RESUMO

BACKGROUND: Moving into a long-term care facility (LTCF) can reduce the ability for older adults to engage in meaningful roles and activities and the size of their social network. These changes and losses can lead them to experience existential loneliness (EL)-the intolerable emptiness and lack of meaningful existence resulted from the losses they have experienced. While EL has often been understood as a universal human experience, it has primarily been studied in people from Western cultures; little is known about how EL may be experienced by and manifested in people from Eastern cultures. Hence, this qualitative study aimed to describe the experience and coping of EL in Hong Kong Chinese and Swedish older adults living in LTCFs. METHODS: A qualitative study using Thorne's (2004) interpretive description was conducted. Thirteen Chinese and 9 Swedes living in LTCFs in Hong Kong, China and Malmo, Sweden, respectively were interviewed about their experience of EL in two series of semi-structured interviews. Data were analyzed using thematic analysis. RESULTS: The core theme of "overcoming EL" described the participants' experience of EL, which came about through the combined process of "Feeling EL" and "Self-Regulating". Both Chinese and Swedish participants had similar experience with EL. Realizing that they did not want to living with EL anymore, they coped by reframing their experience and identifying new meaning in their life. CONCLUSIONS: The study findings suggested that early and clear counselling support that help older adults to define new meaning in life may help them cope. In addition, more opportunities should be available at the LTCFs to promote quality relationships, enable older adults to reflect on their lives with pride, and support their ability to do the things they enjoy.


Assuntos
Envelhecimento/psicologia , Comparação Transcultural , Idoso Fragilizado/psicologia , Solidão/psicologia , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Hong Kong , Humanos , Vida Independente/psicologia , Entrevistas como Assunto , Assistência de Longa Duração , Masculino , Pesquisa Qualitativa , Qualidade de Vida , Suécia
3.
Hum Reprod ; 32(2): 383-390, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27999119

RESUMO

STUDY QUESTION: How do transgender men experience fertility preservation (FP) by cryopreservation of oocytes? SUMMARY ANSWER: The procedures required prior to oocyte cryopreservation, such as hormonal ovarian stimulation and transvaginal ultrasound (TVS), have a negative impact on gender dysphoria as they are closely linked to the men's female assigned sex at birth, which is incompatible with their current status. WHAT IS KNOWN ALREADY: Transgender persons often have high dissatisfaction with assigned sex-specific body features, such as the genital organs and androgen/oestrogen-responsive features. Thus, undergoing FP that requires genital-specific examinations, aimed at obtaining oocytes to cryopreserve, could be distressing. As no previous studies have investigated transgender men's experiences of FP involving cryopreservation of oocytes, little is known about their experience of the procedures. STUDY DESIGN, SIZE, DURATION: This is a prospective study among adult transgender men referred for FP between March 2014 and December 2015. Individual in-depth qualitative interviews were conducted shortly after FP treatment. The interviews lasted between 62 and 111 min (mean 81 min) and were digitally recorded and transcribed verbatim. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were recruited on their first visit to the assisted reproduction clinic for reproductive counseling. There were 15 men, scheduled for FP, who chose to participate in the study (age 19-35); none had given birth and eight had a partner. Data were analyzed by thematic content analysis. MAIN RESULTS AND THE ROLE OF CHANCE: The analysis resulted in three main categories: the journey to FP, reactions to the FP proceedings and strategies for coping. The referral for FP was an important part of the assessment and diagnosis and sometimes lined with frustrating waits and doubts. The reaction to the FP proceedings revealed that the genital examinations and the physical changes associated with discontinuation of testosterone or hormonal stimulation treatment triggered gender incongruence and dysphoria. However, for some, the negative expectations were not met. The participants used several coping strategies in order to manage the procedure, such as focusing on their reasons for undergoing FP, reaching out to friends and family for support and the cognitive approaches of not hating their body or using non-gendered names for their body parts. The results demonstrate the importance of contextual sensitivity during FP procedures. LIMITATIONS, REASONS FOR CAUTION: The authors have strived to be reflective about their pre-understanding of the phenomenon. The majority of the participants resided in large urban areas; it is possible that transgender men living in rural areas have different experiences. WIDER IMPLICATIONS OF THE FINDINGS: As the results are based on qualitative data from 15 transgender men, the results cannot readily be generalized to larger populations. However, the results are suggested to be applicable to other transgender men who want to undergo FP by cryopreservation of oocytes. The results show that transgender men's experience of FP places may elicit gender incongruence and gender dysphoria. However, health care personnel can alleviate distress by using a gender-neutral language and the preferred pronoun. Also, reassuringly, the men also have coping strategies of how to handle the situation. This knowledge is important to ensure adequate professional support for patients with gender dysphoria during FP. STUDY FUNDING/COMPETING INTERESTS: Swedish Society of Medicine, Stockholm County Council and Karolinska Institutet (to K.A.R.-W.). TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Adaptação Psicológica/fisiologia , Aconselhamento , Criopreservação , Preservação da Fertilidade/psicologia , Oócitos , Pessoas Transgênero/psicologia , Adulto , Feminino , Humanos , Masculino , Homens , Estudos Prospectivos , Pesquisa Qualitativa , Adulto Jovem
6.
J Mater Sci Mater Med ; 23(8): 1879-89, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22689010

RESUMO

Wear particles from the bearing surfaces of joint implants are one of the main limiting factors for total implant longevity. Si(3)N(4) is a potential wear resistant alternative for total joint replacements. In this study, Si(x)N(y)-coatings were deposited on cobalt chromium-discs and Si-wafers by a physical vapour deposition process. The tribological properties, as well as surface appearance, chemical composition, phase composition, structure and hardness of these coatings were analysed. The coatings were found to be amorphous or nanocrystalline, with a hardness and coefficient of friction against Si(3)N(4) similar to that found for bulk Si(3)N(4). The low wear rate of the coatings indicates that they have a potential as bearing surfaces of joint replacements. The adhesion to the substrates remains to be improved.


Assuntos
Ligas de Cromo/química , Materiais Revestidos Biocompatíveis/química , Prótese Articular , Compostos de Silício/química , Adesividade , Fricção , Dureza , Lubrificação , Teste de Materiais , Propriedades de Superfície
7.
Eur Arch Otorhinolaryngol ; 269(3): 891-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21947433

RESUMO

Sarcoidosis is a chronic systemic disease of unknown etiology characterized by non-caseating inflammation involving one or more organs with predilection for pulmonary and upper respiratory tract involvement. It presents with a variety of signs and symptoms which can be generalized or focused on a single organ. Sinonasal involvement is reported in about 1% of cases of sarcoidosis. Sarcoidosis can involve both the mucosa as well as bony structures in the nose and the paranasal sinuses. We present seven cases of sarcoidosis with sinonasal involvement. Four cases presented with nasal and sinus symptoms, and the other three cases developed or presented with nasal and sinus symptoms after the diagnosis of sarcoidosis was confirmed. The nasal and sinus symptoms in these patients were managed by local and systemic steroids. In four patients, endoscopic sinus surgery was performed with good outcome. Nasal and sinus symptoms, differential diagnosis and the treatment are discussed.


Assuntos
Endoscopia/métodos , Glucocorticoides/administração & dosagem , Doenças Nasais/diagnóstico , Doenças dos Seios Paranasais/diagnóstico , Sarcoidose/diagnóstico , Adulto , Biópsia , Diagnóstico Diferencial , Vias de Administração de Medicamentos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Nasais/terapia , Doenças dos Seios Paranasais/terapia , Estudos Retrospectivos , Sarcoidose/terapia , Tomografia Computadorizada por Raios X
8.
Scand J Immunol ; 74(2): 114-25, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21388428

RESUMO

Interaction between the immune system and cancer allows for the use of biological response modifiers, e.g. OK-432, in cancer therapy. OK-432, penicillin-killed Streptococcus pyogenes, is used in treating carcinomas, but also lymphangiomas. We have studied the role of monocytes (MOs) in the immune response to OK-432 by examining IL-6 and tumour necrosis factor (TNF)-α secretion after in vitro MO stimulation with OK-432, to some extent in comparison with lipoteichoic acid (LTA) and lipopolysaccharide (LPS). LTA stimulation of whole blood gave IL-6 but not TNF-α secretion, as previously shown with OK-432 stimulation, whereas both cytokines were secreted following LPS stimulation. Addition of the MAPK kinase (MAPKK) MEK inhibitor U0126 inhibited IL-6/TNF-α secretion in a dose-dependent manner. Flow cytometry and to some extent Western blot (Wb) analyses showed that MAPK ERK, located downstream of MEK1/2, is predominantly phosphorylated at isolation from peripheral blood. Addition of the p38 MAP kinase inhibitor SB202190 decreased MO IL-6/TNF-α production upon OK-432 stimulation in a dose-dependent manner. Addition of the MAPK JNK inhibitor SP600125 did not systematically change the MO IL-6/TNF-α OK-432 response. Flow cytometry showed that when stimulating the MOs before isolation from blood, LPS yielded ERK phosphorylation and LPS/LTA p38 phosphorylation, whereas OK-432 had no effects on phosphorylation levels. In conclusion, we have shown that OK-432 resembles TLR2 more than TLR4 stimulation of MOs and depends on MAPKK MEK and MAPK p38, but not on JNK phosphorylation. The MEK and p38 MO OK-432 stimulation dependence is possibly related to the differentiation of cells of the MO lineage.


Assuntos
Antineoplásicos/farmacologia , Interleucina-6/imunologia , Leucócitos Mononucleares/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/imunologia , Picibanil/farmacologia , Fator de Necrose Tumoral alfa/imunologia , Antracenos , Butadienos/farmacologia , Células Cultivadas , Inibidores Enzimáticos/imunologia , Inibidores Enzimáticos/farmacologia , Humanos , Imidazóis/farmacologia , Interleucina-6/biossíntese , Interleucina-6/metabolismo , Leucócitos Mononucleares/enzimologia , Leucócitos Mononucleares/imunologia , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Nitrilas/farmacologia , Fosforilação , Piridinas/farmacologia , Ácidos Teicoicos/imunologia , Ácidos Teicoicos/farmacologia , Fator de Necrose Tumoral alfa/biossíntese
9.
Clin Otolaryngol ; 36(4): 361-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21624101

RESUMO

OBJECTIVE: To examine the survival prediction of long-term health-related quality of life in patients with head and neck squamous cell carcinoma. DESIGN: Patients with head and neck squamous cell carcinoma diagnosed in the period between July 1992 and October 2001, who had been disease free for a minimum of 1 year following therapy, responded to structured interviews including several validated questionnaires in the period from October 2002 to March 2004. The study ended in June 2009 with a mean observation time of 75 ± 4 months among the survivors. Twenty-four deaths were observed. SETTING: University hospital, referral centre of the Western Norway. PARTICIPANTS: One hundred and thirty-nine cognitive functioning patients. MAIN OUTCOME MEASUREMENTS: Overall survival as of June 2009. This was correlated with various clinical factors and the EORTC QLQ-C30 questionnaire, the Eysenck Personality Inventory and the Coping inventory completed between October 2001 and March 2004. RESULTS: A general symptom sum score was significantly predictive of survival directly and after sequential adjustment for self-reported levels of neuroticism, avoidance focused coping, coping by suppression of competing activity, alcohol consumption, smoking status and heart/lung disease, as well as gender, age, time between diagnosis and inclusion, tumour node metastasis (TNM) stage and tumour site. Similar results were found for the health-related quality of life indices 'fatigue', 'dyspnoea' and 'sleep disturbance'. A dichotomised variable based on the general symptom sum score was calculated, and a high risk group, as to mortality, including less than a quintile of the total patient population was established. A hazard ratio of 5.15 was found for the dichotomised general symptom sum score. CONCLUSION: We have shown a unique and independent survival prediction from long-term EORTC QLQ-C30 scores in successfully treated and cognitive functioning head and neck squamous cell carcinoma patients.


Assuntos
Adaptação Psicológica , Carcinoma de Células Escamosas/psicologia , Neoplasias de Cabeça e Pescoço/psicologia , Qualidade de Vida , Inquéritos e Questionários , Sobreviventes/psicologia , Carcinoma de Células Escamosas/mortalidade , Intervalo Livre de Doença , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida/tendências , Sobreviventes/estatística & dados numéricos
10.
Scand J Immunol ; 67(4): 392-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18282234

RESUMO

Co-culture of monocytes with autologous fragment (F) spheroids originating from malignant (M) tumour or benign (B) control mucosa of head and neck squamous cell carcinoma (HNSCC) yields interleukin (IL)-6 and monocyte chemo-attractant protein (MCP)-1 secretion. This study investigates the association between this cytokine co-culture response and prognosis. Analysis of IL-6 and MCP-1 content of supernatants from monocytes in vitro co-culture with autologous MF- or BF-spheroids was investigated in a cohort of HNSCC patients (n = 65) diagnosed between 1998 and 2005, all of whom were treated with curative intent by primary surgery. The IL-6 response was expressed as a fraction of the lipopolysaccharid response of the same batch of monocytes. Recurrence, survival and causes of death were then established following the second part of 2005. MCP-1 levels did not predict prognosis. We found that increased levels of IL-6 from autologous monocytes in co-culture with MF-spheroids predicted recurrence with a hazard ratio (HR) of 1.5 [confidence interval (CI): 1.01-2.60; P = 0.05] and co-culture with BF-spheroids and monocytes predicted recurrence (HR = 4.17; CI: 1.54-11.29; P = 0.005). The same results where obtained in addition with TNM stage of the patients. Simultaneous analysis of BF- and MF-spheroid co-culture IL-6 responses as well as adjustment for age and TNM stage of the patients allowed prediction of total survival (HR = 3.1; CI: 1.11-8.56; P = 0.03) based on BF co-culture levels. IL-6 secreted upon in vitro co-culture with monocytes and BF-spheroids predicts recurrence and prognosis, whereas co-culture with monocytes and MF-spheroids predicts recurrence.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/imunologia , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/imunologia , Monócitos/imunologia , Biomarcadores/metabolismo , Quimiocina CCL2/metabolismo , Técnicas de Cocultura , Humanos , Interleucina-6/metabolismo , Monócitos/metabolismo , Prognóstico , Recidiva , Esferoides Celulares , Células Tumorais Cultivadas
11.
Scand J Immunol ; 66(6): 684-93, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18021366

RESUMO

OK-432, penicillin-killed Streptococcus pyogenes, is used in treating lymphangiomas and carcinomas. We have studied proinflammatory interleukin (IL) secretion following OK-432 stimulation of total blood, peripheral blood mononuclear cell (PBMC) and purified monocytes in vitro. OK-432 stimulation of purified monocytes gave IL-1beta, IL-1RA, IL-6, IL-12p40 and tumour necrosis factor (TNF)-alpha response. OK-432 stimulation of cells within blood did, however, not yield TNF-alpha secretion. When PBMC or monocytes were cultured in low-attachment wells a decreased IL secretion was observed compared to adherent cells. Inhibition of Syk kinase with piceatannol, only at high, non-specific doses, but not PI3 kinase inhibition with LY294002 or Wortmannin, decreased monocyte IL response to OK-432. This shows that beta(1-3)-integrin receptor function is not necessary for monocyte OK-432-stimulated TNF-alpha secretion. Direct blockage of the beta(2)-integrin (CD18) receptor by anti-CD18 antibody was also unable to prevent the stimulating effects of OK-432 in human monocytes. On the other hand, Syk phosphorylation is elevated upon adherence of monocytes and this is further increased by OK-432 stimulation, as shown by Western blot. The Fc-receptor was also ruled out as a main receptor of the OK-432 monocyte response. In conclusion, TNF-alpha secretion is only found in monocytes removed from blood. This TNF-alpha secretion is not mediated through the beta(1-3)-integrin receptors. OK-432 may act as a target-seeking substance whereby only monocytes adhered, e.g. to a tumour cell, become cytotoxic in part explaining why OK-432 is well suited as a cancer treatment drug.


Assuntos
Neoplasias de Cabeça e Pescoço/sangue , Macrófagos/imunologia , Monócitos/metabolismo , Picibanil/administração & dosagem , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Adesão Celular/imunologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Citotoxicidade Imunológica/efeitos dos fármacos , Inibidores Enzimáticos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imunidade Celular/efeitos dos fármacos , Interferon gama/imunologia , Interleucinas/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/química , Lipopolissacarídeos/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Macrófagos/citologia , Masculino , Pessoa de Meia-Idade , Monócitos/citologia , Monócitos/imunologia , Picibanil/sangue , Picibanil/química , Proteínas Tirosina Quinases/antagonistas & inibidores , Valores de Referência , Quinase Syk
12.
J Neonatal Perinatal Med ; 10(1): 63-70, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28304314

RESUMO

OBJECTIVE: To evaluate the duration of catheter stay, incidence of non-elective removal and rates of complications associated with peripherally inserted central catheters (PICCs) in relation to different catheter positions in extremely preterm infants (EPT, <28 weeks of gestation). METHODS: A retrospective analysis of Peripherally Inserted Central Catheters (PICCs) inserted in EPT infants over a 10-year period, from January 2004 through December 2013 (mean gestational age, 25.2 weeks; mean birth weight, 727 g). RESULTS: Of the 379 PICCs analyzed, the majority of lines (68%) were placed in the central position, and 259 PICCs (56%) were removed electively after fulfilment of the treatment. Significantly more PICCs in the lower extremities compared to the upper extremities were in central positions (86% vs 61%, p < 0.001, respectively). Significantly more PICCs that were removed electively after fulfilment of the treatment were in a central position compared to a non-central position (p < 0.001). Of the 166 catheters that were removed because of complications, most (71%) of them had mechanical problems, and 13% had sepsis resulting in an incidence rate of 4.4/1000 catheter days. CONCLUSION: PICCs inserted in the lower extremity were more likely to have a centrally placed tip position compared to PICC lines inserted in the upper extremities.


Assuntos
Infecções Relacionadas a Cateter/epidemiologia , Cateterismo Periférico/métodos , Remoção de Dispositivo/estatística & dados numéricos , Sepse/epidemiologia , Infecções Relacionadas a Cateter/etiologia , Cateterismo Periférico/efeitos adversos , Cateteres Venosos Centrais , Feminino , Idade Gestacional , Humanos , Incidência , Lactente Extremamente Prematuro , Recém-Nascido , Masculino , Estudos Retrospectivos , Sepse/etiologia
13.
Phys Med Biol ; 51(16): 4111-8, 2006 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-16885628

RESUMO

Standard treatment machines for external radiotherapy are designed to yield flat dose distributions at a representative treatment depth. The common method to reach this goal is to use a flattening filter to decrease the fluence in the centre of the beam. A side effect of this filtering is that the average energy of the beam is generally lower at a distance from the central axis, a phenomenon commonly referred to as off-axis softening. The off-axis softening results in a relative change in beam quality that is almost independent of machine brand and model. Central axis dose calculations using pencil beam kernels show no drastic loss in accuracy when the off-axis beam quality variations are neglected. However, for dose calculated at off-axis positions the effect should be considered, otherwise errors of several per cent can be introduced. This work proposes a method to explicitly include the effect of off-axis softening in pencil kernel based photon dose calculations for arbitrary positions in a radiation field. Variations of pencil kernel values are modelled through a generic relation between half value layer (HVL) thickness and off-axis position for standard treatment machines. The pencil kernel integration for dose calculation is performed through sampling of energy fluence and beam quality in sectors of concentric circles around the calculation point. The method is fully based on generic data and therefore does not require any specific measurements for characterization of the off-axis softening effect, provided that the machine performance is in agreement with the assumed HVL variations. The model is verified versus profile measurements at different depths and through a model self-consistency check, using the dose calculation model to estimate HVL values at off-axis positions. A comparison between calculated and measured profiles at different depths showed a maximum relative error of 4% without explicit modelling of off-axis softening. The maximum relative error was reduced to 1% when the off-axis softening was accounted for in the calculations.


Assuntos
Modelos Biológicos , Fótons/uso terapêutico , Garantia da Qualidade dos Cuidados de Saúde/métodos , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Simulação por Computador , Controle de Qualidade , Dosagem Radioterapêutica , Eficiência Biológica Relativa , Reprodutibilidade dos Testes , Espalhamento de Radiação , Sensibilidade e Especificidade
14.
AIDS ; 13(17): 2365-76, 1999 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-10597778

RESUMO

OBJECTIVES: To study the effects of antiretroviral therapy on T cell activation in blood and tonsils from HIV-1 infected individuals in relation to CD4 cell count, plasma viremia, and infectious HIV-1 provirus. DESIGN: A 48-week study of viral load and T cell subsets in blood and tonsils from 12 HIV-1-positive individuals with a mean CD4 cell number of 400 x 10(6) cells/l treated with a combination of zidovudine, lamivudine, and indinavir. METHODS: Tonsil biopsies and blood samples were collected at regular intervals. Lymphocytes were phenotyped and quantified by three-color flow cytometry; infectious provirus was quantified by a limiting dilution assay. HIV-1-negative individuals were included as controls. RESULTS: The fraction of tonsillar CD8 T cells expressing CD69, CD38, or HLA-DR in the patients with suppressed virus replication declined to levels comparable with that in controls by 48 weeks and showed a strong positive correlation with tonsillar infectious provirus and plasma viremia. The level of CD4 T cell activation was within normal range in tonsils throughout the study. The fraction of HLA-DR+ cells within CD4 and CD8 T cells in blood declined rapidly in parallel with plasma viremia but remained slightly higher compared with that in uninfected individuals. CONCLUSION: Antiretroviral therapy normalizes tonsillar CD8 T cell activation in HIV-1-positive individuals in parallel with suppression of viral replication, indicating reduced CD8 cell turnover. Normal tonsillar CD4 T cell activation suggests limited CD4 cell turnover in early HIV infection. Activated CD8 T cells in lymphoid tissue is superior to that in blood as an immunological marker for the virological response to antiretroviral therapy.


Assuntos
Antígenos CD , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Tonsila Palatina/virologia , Provírus/isolamento & purificação , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Adulto , Fármacos Anti-HIV/administração & dosagem , Antígenos de Diferenciação/metabolismo , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Feminino , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Antígenos HLA-DR/metabolismo , Humanos , Indinavir/administração & dosagem , Lamivudina/administração & dosagem , Ativação Linfocitária , Masculino , Glicoproteínas de Membrana , NAD+ Nucleosidase/metabolismo , Subpopulações de Linfócitos T/imunologia , Fatores de Tempo , Viremia/tratamento farmacológico , Viremia/imunologia , Viremia/virologia , Replicação Viral/efeitos dos fármacos , Zidovudina/administração & dosagem
15.
AIDS ; 10(10): F35-8, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8874620

RESUMO

OBJECTIVE: To investigate whether the loss of CD4 cells seen in peripheral circulation of HIV-1-positive individuals reflects a similar depletion of CD4 cells from lymphoid tissue. DESIGN: CD4 and CD8 cells in tonsillar mononuclear cell suspensions were quantified relative to tonsillar B cells, as these were thought to remain numerically unchanged in the course of HIV infection. Results were related to the CD4 cell counts in blood and to the clinical status of the patients. METHODS: Blood samples and tonsillar tissue were obtained from 13 HIV-1-seropositive individuals and six seronegative controls. B cells and T-cell subsets in mononuclear cells were quantified using a three-colour flow cytometry protocol. Histological sections were morphologically classified and B-cell areas were quantified by morphometry. RESULTS: The B-cell fraction was confirmed to be relatively unchanged in asymptomatic HIV-1-seropositive individuals compared with controls. The tonsillar CD4 : B-cell ratios in asymptomatic individuals was similar to those seen in controls, whereas the CD4 : B-cell ratios in symptomatic HIV-1-infected individuals were greatly reduced. The tonsillar CD4 : CD8 cell ratios in HIV-1-infected individuals were much lower than those seen in controls, in the asymptomatic group due to a considerable expansion of the tonsillar CD8 cell subset, and in the symptomatic group also due to a loss of CD4 cells. CONCLUSIONS: We found no evidence of CD4 cell depletion in tonsillar tissue in asymptomatic HIV-1-infected individuals despite low CD4 cell counts in blood. Loss of CD4 cells from this lymphoid tissue seems to occur as a late-stage phenomenon correlated with the onset of clinical symptoms.


Assuntos
Contagem de Linfócito CD4/métodos , Infecções por HIV/imunologia , HIV-1 , Tonsila Palatina/imunologia , Adulto , Linfócitos B , Infecções por HIV/etiologia , Humanos , Contagem de Linfócitos , Padrões de Referência
16.
Endocrinology ; 120(1): 107-14, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3780557

RESUMO

It is well known that LH and human CG (hCG) induce an increase in total ovarian blood flow. The effect of LH/hCG on luteal blood flow, however, is unknown. This work studies the effect of hCG on both luteal and ovarian blood flows at different stages of pseudopregnancy in adult female rats. Pseudopregnancy was induced by mating with sterile male rats. The length of pseudopregnancy was 13 +/- 1 days and, during this time, blood flow was measured by the injection of radioactive microspheres during anesthesia. At autopsy, the corpora lutea were identified and extirpated under a stereomicroscope. These, and the remaining ovary, were then counted for radioactivity and the blood flow was calculated. Progesterone levels were determined in plasma and ovarian tissues. Furthermore, the responsiveness of adenylate cyclase was tested in ovarian tissues at day 6 of pseudopregnancy. An intraarterial injection of hCG (50 IU) or vehicle (saline) was given 20 min before the blood flow determinations in anesthetized rats. The luteal blood flow was not changed by hCG on days 2, 6, and 11 of pseudopregnancy, whereas in the remaining ovary the blood flow increased more than 2-fold, thereby resulting in redistribution of the blood flow. Ten micrograms of NIH-LH-B9, tested at day 6 of pseudopregnancy, mimicked the effect of hCG. At day 6 of pseudopregnancy, hCG (50 IU) was given ip to conscious rats 200 min and 24 h before blood flow determinations. At 200 min after hCG there was a more pronounced redistribution of ovarian blood flow with a 45% reduction in luteal blood flow and a 4-fold increase in flow through the remaining ovary. LH as well as hCG doubled the progesterone content of the remaining ovary. In the corpora lutea an increased progesterone content was seen after 200 min of hCG exposure. At 24 h after hCG injection, all parameters had returned to control levels except that adenylate cyclase was nonresponsive. The increase in the total ovarian blood flow coincides with the increased steroidogenesis and these effects are likely due to release of metabolites and/or vasoactive substances. Despite this increase, the blood flow of the corpus luteum was not increased rendering vascular mechanisms unlikely as a part of the acute LH/hCG effects on corpus luteum of pseudopregnancy.


Assuntos
Gonadotropina Coriônica/farmacologia , Hormônio Luteinizante/farmacologia , Ovário/irrigação sanguínea , Pseudogravidez/fisiopatologia , Adenilil Ciclases/metabolismo , Animais , Feminino , Progesterona/metabolismo , Ratos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fatores de Tempo
17.
Endocrinology ; 136(3): 974-80, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7867607

RESUMO

The reverse transcription-polymerase chain reaction was used to evaluate the influence of gonadotropins and GnRH on GnRH receptor gene expression in cultured preovulatory rat granulosa cells. Cells were obtained from immature female rats 48 h after priming with 10 IU PMSG, sc, and cultured in medium containing LH, FSH, or GnRH after a 24-h preincubation period. After culture, cells were lysed, total RNA was extracted, and culture medium was assayed for its content of progesterone, and estradiol by RIA. Subsequent to reverse transcription, complementary DNA was subjected to polymerase chain reaction, after which the products formed were transferred to nylon filters and hybridized with a 416-basepair internal rat GnRH receptor complementary DNA probe. As an amplification control, Southern hybridization of glyceraldehyde-3-phosphate dehydrogenase messenger RNA (mRNA) was performed. Treatment with LH increased both progesterone and estradiol output, whereas GnRH receptor mRNA levels were markedly suppressed in a dose-related fashion, with maximal inhibition seen at 100-1000 ng (P < 0.05). In contrast, FSH in concentrations between 1-1000 ng was without effect on GnRH receptor gene expression. Time-course analysis revealed that GnRH receptor gene expression was not affected by LH (1000 ng) until 12 h, when transcript levels fell to 24% of those seen at 0 h (P < 0.05). This pronounced decrease in GnRH receptor mRNA abundance is, however, transient, because after 48 h, levels returned to those seen before LH treatment. As GnRH has been postulated to directly influence its own receptor synthesis in the pituitary, the effect of GnRH treatment of granulosa cells during a 24-h culture period was also evaluated. In GnRH-treated cells, a dose-dependent increase in GnRH receptor mRNA levels was seen, with maximal effects (2.4-fold; P < 0.05) at 10(-6) M. The demonstration of agonist-specific up- and down-regulation of GnRH receptor gene expression in preovulatory granulosa cells adds further support to the extrapituitary actions of GnRH as an important autocrine/paracrine factor involved in the regulatory events during the periovulatory period.


Assuntos
Fase Folicular , Regulação da Expressão Gênica , Células da Granulosa/fisiologia , Receptores LHRH/genética , Animais , Sequência de Bases , Feminino , Hormônio Foliculoestimulante/farmacologia , Gliceraldeído-3-Fosfato Desidrogenases/genética , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Luteinizante/farmacologia , Sondas Moleculares/genética , Dados de Sequência Molecular , Ratos
18.
Endocrinology ; 140(11): 5330-8, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10537164

RESUMO

The corpus luteum (CL) is a transient endocrine organ that secretes progesterone to support pregnancy. The CL is formed from an ovulated follicle in a process that involves extensive angiogenesis and tissue remodeling. If fertilization does not occur or implantation is unsuccessful, the CL will undergo regression, which involves extensive tissue degradation. Extracellular proteases, such as serine proteases and matrix metalloproteinases (MMPs), are thought to play important roles in both the formation and regression of the CL. In this study, we have examined the physiological regulation pattern and cellular distribution of messenger RNAs coding for gelatinase A (MMP-2), collagenase-3 (MMP-13), membrane type MMP 1 (MT1-MMP, MMP-14), and the major MMP inhibitor, tissue inhibitor of MMPs type 1 (TIMP-1) in the CL of adult pseudopregnant (psp) rat. Northern blot and in situ hybridization analyses revealed that gelatinase A messenger RNA was mainly expressed during luteal development, indicating that gelatinase A may be associated with the neovascularization and tissue remodeling that takes place during CL formation. Collagenase-3 had a separate expression pattern and was only expressed in the regressing CL, suggesting that this MMP may be related with luteal regression. MT1-MMP that in vitro can activate progelatinase A and procollagenase-3 was constitutively expressed during the formation, function, and regression of the CL and may therefore be involved in the activation of these MMPs. TIMP-1 was induced during both the formation and regression of the CL, suggesting that this inhibitor modulates MMP activity during these processes. To test whether the induction of collagenase-3 and TIMP-1 is coupled with luteal regression, we prolonged the luteal phase by performing hysterectomies, and induced premature luteal regression by treating the pseudopregnant rats with a PGF2alpha analog, cloprostenol. In both treatments, collagenase-3 and TIMP-1 were induced only after the serum level of progesterone had decreased, suggesting that collagenase-3 and TIMP-1 are induced by physiological signals, which initiate functional luteolysis to play a role in tissue degradation during structural luteolysis. In conclusion, our data suggest that gelatinase A, collagenase-3, and MT1-MMP may have separate functions during the CL life span: gelatinase A mainly takes part in CL formation, whereas collagenase-3 mainly takes part in luteal regression; MT1-MMP is constitutively expressed during the CL life span and may therefore serve as an in vivo activator of both gelatinase A and collagenase-3. TIMP-1 is up-regulated both during the formation and regression of the CL and may therefore regulate MMP activity during both processes.


Assuntos
Colagenases/genética , Corpo Lúteo/fisiologia , Luteólise/fisiologia , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 2 da Matriz/genética , Metaloproteinases da Matriz/genética , Inibidor Tecidual de Metaloproteinase-1/genética , Animais , Northern Blotting , Cloprostenol/farmacologia , Dinoprosta/análogos & derivados , Feminino , Regulação da Expressão Gênica , Histerectomia , Hibridização In Situ , Fase Luteal/fisiologia , Metaloproteinase 13 da Matriz , Pseudogravidez , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley
19.
Eur J Cancer ; 39(13): 1852-60, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12932662

RESUMO

The aim of the present study was to investigate the association between self-reported quality of life (QoL) and personality in successfully treated primary head and neck squamous cell carcinoma (HNSCC) patients. We determined QoL using the European Organisation for Research and Treatment of Cancer Quality of life Questionnaire (EORTC-QLQ) C30/H and N35, and personality by the Eysenck Personality Inventory (EPI). All patients younger than 80 years who had been diagnosed with HNSCC in Western Norway in the period from 1992 to 1997, and who had survived until 1999, were sampled. 96 patients (a 90% response rate) were included. Questionnaires were also mailed to all Norwegian laryngectomised patients; 104 patients returned the questionnaires (a 50% response rate). The neuroticism scores were test re-test reliable as determined by the neuroticism scores measured at the primary HNSCC diagnosis for a sub-sample (N=22) of the included patients. High neuroticism was associated with a low QoL in both patient samples. The neuroticism score was associated with the QLQ-C30 scales (common variance: 17-25%) and all QoL scores in the laryngectomised group (common variance: 11-25%), and the H and N35 symptom scores in the laryngectomised sample. The associations could still be shown when adjustments were made for gender, age, marital status, educational level, number of children and level of treatment. Extraversion was associated with general QoL, physical and emotional scores in the HNSCC patient sample. Radiation therapy in the HNSCC sample was associated with the H and N35 symptom scores, but different ones to those associated with neuroticism. In conclusion, high neuroticism, but not extraversion, is associated with a lowered QoL.


Assuntos
Carcinoma de Células Escamosas/psicologia , Neoplasias de Cabeça e Pescoço/psicologia , Personalidade , Qualidade de Vida , Adolescente , Adulto , Fatores Etários , Idoso , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Criança , Feminino , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia , Nível de Saúde , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Transtornos Neuróticos/etiologia , Fatores Sexuais , Inquéritos e Questionários
20.
AIDS Res Hum Retroviruses ; 16(3): 191-201, 2000 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-10710207

RESUMO

Antiretroviral therapy increases the number of both CD4+ and CD8+ T cells in the blood of HIV-1-positive patients with advanced disease. In the present study, we have examined the kinetics of CD4+ and CD8+ T cell restoration in blood and lymphoid tissue in asymptomatic HIV-1-positive individuals with high CD4+ cell counts during highly active antiretroviral treatment. Tonsillar biopsies and blood samples were collected at baseline and at regular intervals during the following 48 weeks and from HIV-1-negative controls. Mononuclear cells from blood and tonsils were phenotyped and quantified by three-color flow cytometry. After 48 weeks of therapy, blood CD4+ cell counts in the HIV-1-infected group were comparable to those found in uninfected controls. Naive CD4+ T cells in blood increased during the initial 2 weeks in parallel with reduced plasma viremia. Both naive and memory CD4+ T cells in blood reached normal numbers by week 48, whereas the CD4+ naive/memory cell ratio in tonsils was within normal range throughout the study. The level of memory CD8+ T cells in blood declined during the first 8 weeks in parallel with a reduction in the tonsillar memory CD8+ T cells. Naive CD8+ T cells in the blood increased after 4 weeks, while the level of naive CD8+ T cells in tonsils remained unaltered. Our data indicate that in the early stages of HIV-1 infection antiretroviral therapy normalizes CD4+ cell counts and causes a decrease in the level of memory CD8+ cells in blood and lymphoid tissue, suggesting reduced CD8+ cell turnover in response to reduced viral replication.


Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Infecções por HIV/imunologia , HIV-1/imunologia , Memória Imunológica , Tonsila Palatina/citologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Quimioterapia Combinada , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/fisiopatologia , Infecções por HIV/virologia , Inibidores da Protease de HIV/uso terapêutico , HIV-1/genética , Humanos , Indinavir/uso terapêutico , Lamivudina/uso terapêutico , Masculino , Tonsila Palatina/patologia , Inibidores da Transcriptase Reversa/uso terapêutico , Subpopulações de Linfócitos T/imunologia , Fatores de Tempo , Viremia , Zidovudina/uso terapêutico
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