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1.
Ultrasound Obstet Gynecol ; 58(5): 766-772, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33587289

RESUMO

OBJECTIVE: To evaluate the feasibility and clinical application of fusion imaging with virtual navigation, combining 18 F-fluorodeoxyglucose (18 F-FDG) positron emission tomography/computed tomography (PET/CT) with real-time ultrasound imaging, in assessing superficial lymph nodes in breast-cancer and gynecological-cancer patients. METHODS: This was a pilot study of breast- and gynecological-cancer patients with abnormal uptake of 18 F-FDG by axillary or groin lymph nodes on PET/CT scan, examined at our institution between January 2017 and May 2019. Fusion imaging was performed, uploading preacquired PET/CT DICOM images onto the ultrasound machine and synchronizing them with real-time ultrasound scanning performed at the lymph-node site. In the first phase, we assessed the feasibility and reliability of fusion imaging in a series of 10 patients with suspicious lymph nodes on both PET/CT and ultrasound, and with full correspondence between both techniques in terms of size, shape and morphology of the lymph nodes (Group A). In the second phase, we included 20 patients with non-corresponding findings between PET/CT and ultrasound: 10 patients with lymph nodes that were suspicious or pathological on PET/CT scan but not suspicious on ultrasound assessment (Group B), and 10 patients with suspicious or pathological lymph nodes on both PET/CT and ultrasound but with no correspondence between the two techniques in terms of number of affected lymph nodes (Group C). RESULTS: In the 30 selected patients, fusion imaging was assessed at 30 lymph-node sites (22 inguinal and eight axillary nodes). In the first phase (Group A), the fusion technique was shown to be feasible in all 10 lymph-node sites evaluated. In the second phase, fusion imaging was completed successfully in nine of 10 cases in Group B and in all 10 cases in Group C. In all groups, fusion imaging was able to identify the target lymph node, guiding the examiner to perform a core-needle aspiration biopsy or to inject radiotracer for selective surgical nodal excision, according to the radio-guided occult lesion localization technique. CONCLUSION: Fusion imaging with virtual navigation, combining PET/CT and real-time ultrasound imaging, is technically feasible and able to detect target lymph nodes even when PET/CT and ultrasound findings are inconsistent. Fusion imaging can also be used to guide the performance of core-needle aspiration biopsy, avoiding further surgical diagnostic procedures, or the injection of radiotracer for selective surgical nodal excision, enabling more sparing, selective surgery. This innovative technique could open up multiple diagnostic and therapeutic opportunities in breast and gynecological oncology. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Imagem Multimodal/estatística & dados numéricos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/estatística & dados numéricos , Ultrassonografia/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Sistemas Computacionais , Estudos de Viabilidade , Feminino , Fluordesoxiglucose F18 , Humanos , Metástase Linfática/diagnóstico por imagem , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Projetos Piloto , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Ultrassonografia/métodos
2.
Ultrasound Obstet Gynecol ; 55(3): 401-410, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31237047

RESUMO

OBJECTIVE: To assess the accuracy of preoperative ultrasound examination for predicting lymph-node (LN) status in patients with vulvar cancer. METHODS: This was a single-institution retrospective observational study of all women with a histological diagnosis of vulvar cancer triaged to inguinal surgery within 30 days following ultrasound evaluation between December 2010 and January 2016. For each groin examined, 15 morphological and dimensional sonographic parameters associated with suspicion for LN involvement were examined. A morphometric ultrasound pattern (MUP) was expressed for each groin, classifying the inguinal LN status into five groups (normal; reactive-but-negative; minimally suspicious/probably negative; moderately suspicious; and highly suspicious/positive) according to subjective judgment, followed by stratification as positive or negative for metastasis according to morphometric binomial assessment (MBA). In cases of positive MBA, fine-needle aspiration cytology was performed. Combining the information obtained from MUP and cytologic results, a binomial final overall assessment (FOA) was assigned for each groin. The final histology was considered as the reference standard. Comparison was performed between patients with negative and those with positive LNs on histology, and receiver-operating-characteristics curves were generated for statistically significant variables on univariate analysis, to evaluate their diagnostic ability to predict negative LN status. RESULTS: Of 144 patients included in the analysis, 87 had negative inguinal LNs and 57 had positive LNs on histology. A total of 256 groins were analyzed, of which 171 were negative and 85 showed at least one metastatic LN on histology. The following parameters showed the greatest accuracy, with the best balance between specificity and sensitivity, in predicting negative LN status: cortical (C) thickness of the dominant LN (cut-off, 2.5 mm; sensitivity, 90.0%; specificity, 77.9%); short-axis (S) length of the dominant LN (cut-off, 8.4 mm; sensitivity, 63.9%; specificity, 90.6%); C/medulla (M) thickness ratio of the dominant LN (cut-off, 1.2 mm; sensitivity, 70.4%; specificity, 91.5%), the combination of S length and C/M thickness ratio (sensitivity, 88.9%; specificity, 82.4%); and the FOA analysis (sensitivity, 85.9%; specificity, 84.2%). CONCLUSIONS: Preoperative ultrasound assessment, with or without the addition of cytology, has a high accuracy in assessing inguinal LN status in patients with vulvar cancer. In particular, the combination of two ultrasound parameters (S length and C/M thickness ratio) provided the greatest accuracy in discriminating between negative and positive LNs. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Biópsia por Agulha Fina/estatística & dados numéricos , Metástase Linfática/diagnóstico por imagem , Cuidados Pré-Operatórios/estatística & dados numéricos , Ultrassonografia/estatística & dados numéricos , Neoplasias Vulvares/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina/métodos , Feminino , Virilha/diagnóstico por imagem , Virilha/patologia , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Período Pré-Operatório , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia/métodos , Neoplasias Vulvares/patologia , Neoplasias Vulvares/cirurgia , Adulto Jovem
3.
Ultrasound Obstet Gynecol ; 54(4): 545-551, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31152573

RESUMO

OBJECTIVE: To evaluate the feasibility of fusion of ultrasound imaging and three-dimensional (3D) single-photon-emission computed tomography/computed tomography (SPECT/CT) in detecting sentinel lymph nodes in women with vulvar cancer. METHODS: This was a prospective pilot single-center study. Patients with vulvar cancer who were candidates for sentinel lymph-node biopsy were enrolled between December 2018 and February 2019. Fusion imaging virtual navigation using 3D SPECT/CT and ultrasound was performed to investigate the tumor-draining lymph node. All clinical, imaging, surgical and histological information was collected prospectively and entered into a dedicated Excel file. Feasibility and success of fusion imaging virtual navigation and time needed to perform the three steps of fusion imaging were evaluated. RESULTS: Ten lymph-node sites were evaluated in five consecutive women with a histological diagnosis of vulvar cancer. Fusion imaging virtual navigation was feasible and completed successfully for all (10/10) draining sites. Median overall time to perform fusion imaging was 32 (range, 25-40) min and the time decreased from the first to the last examination. CONCLUSIONS: The present study demonstrated that fusion imaging virtual navigation using 3D SPECT/CT and ultrasound is feasible and able to detect sentinel lymph nodes in women with vulvar carcinoma. Fusion imaging using ultrasound for detection of sentinel lymph nodes opens up multiple diagnostic and therapeutic opportunities in gynecological oncology. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Imageamento Tridimensional/métodos , Linfonodo Sentinela/diagnóstico por imagem , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Ultrassonografia/instrumentação , Neoplasias Vulvares/patologia , Idoso , Idoso de 80 Anos ou mais , Carcinoma , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Linfonodo Sentinela/patologia , Biópsia de Linfonodo Sentinela/métodos
4.
Eur J Surg Oncol ; 43(9): 1776-1783, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28751058

RESUMO

OBJECTIVE: The study aims were: 1) to verify the role of sentinel node biopsy (SNB) in a subset of patients with clinical N0 (cN0) invasive vulvar cancer (VC) who were still candidates for radical inguinal surgery according to the current guidelines; 2) to investigate whether a preoperative 18F-FDG PET/CT (PET/CT) evaluation could improve the selection of node negative patients. METHODS: From July 2013 to July 2016, all patients with VC admitted to our Division were evaluated by standard imaging and clinical exam. Among the patients assessed as cN0 we enrolled those unsuitable for SNB, due to: T > 4 cm, multifocal tumors, complete tumor diagnostic excision, contralateral nodal involvement and local recurrence. A preoperative PET/CT was performed. For each patient surgery included SNB, performed using a combined technique (radiotracer plus blue dye), followed by standard inguino-femoral lymphadenectomy. The reference standard was histopathology. RESULTS: Forty-seven patients entered the study for a total of 73 groins. Histopathology revealed 12 metastatic SNs in 9 groins. No false negative SNs were found (NPV 100%). PET/CT showed a negative predictive value of 93%. CONCLUSIONS: Our data suggest that SNB is accurate and safe even in cN0 patients currently excluded from this procedure, providing that a careful preoperative selection is performed. PET/CT allows a reliable assessment of LN status and may be an effective support for the selection of patients who are safe candidates for SNB.


Assuntos
Carcinoma/cirurgia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Biópsia de Linfonodo Sentinela , Neoplasias Vulvares/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/diagnóstico por imagem , Carcinoma/secundário , Feminino , Fluordesoxiglucose F18 , Humanos , Canal Inguinal , Linfonodos/cirurgia , Metástase Linfática , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Invasividade Neoplásica , Estadiamento de Neoplasias , Seleção de Pacientes , Projetos Piloto , Valor Preditivo dos Testes , Período Pré-Operatório , Estudos Prospectivos , Compostos Radiofarmacêuticos , Neoplasias Vulvares/diagnóstico por imagem , Neoplasias Vulvares/patologia
5.
Eur Rev Med Pharmacol Sci ; 16(11): 1530-40, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23111966

RESUMO

Oncoplastic surgery of the breast (OPS) has generated great excitement over the past years and has become an integrated component of the surgical treatment of breast cancer. Oncoplastic surgical procedures associate the best surgical oncologic principles to achieve wide tumor-free margins with the best principles of plastic surgery to optimize cosmetic outcomes. Thanks to oncoplastic techniques, the role of breast conserving surgery (BCS) has been extended to include a group of patients who would otherwise require mastectomy to achieve adequate tumor clearance. As OPS continues to gain acceptance and diffusion, an optimal and systematic approach to these techniques is becoming increasingly necessary. This article has the aim to review the essential principles and techniques associated with oncoplastic surgery, based on the data acquired through an extensive search of the PUBMED and MEDLINE database for articles published using the key words "breast cancer oncoplastic surgery". This review analyzes possible the advantages", classifications, indications, and the criteria for a proper selection of oncoplastic techniques to facilitate one's ability to master these procedures and make OPS a safe and an effective procedure.


Assuntos
Neoplasias da Mama/cirurgia , Mamoplastia , Mastectomia Segmentar , Feminino , Humanos
6.
Osteoarthritis Cartilage ; 14(10): 1041-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16769229

RESUMO

OBJECTIVE: In the present study, we sought to develop/characterize the pain profile of a rat model of surgically induced osteoarthritis (OA). METHODS: OA was surgically induced in male Lewis rats (200-225 g) by transection of the medial collateral ligament and medial meniscus of the femoro-tibial joint. In order to characterize the pain profile, animals were assessed for a change in hind paw weight distribution (HPWD), development of mechanical allodynia, and the presence of thermal and mechanical hyperalgesia. Rofecoxib and gabapentin were examined for their ability to decrease change in weight distribution and tactile allodynia. RESULTS: Transection of the medial collateral ligament and medial meniscus of male Lewis rats resulted in rapid (<3 days) changes in hind paw weight bearing and the development of tactile allodynia (secondary hyperalgesia). There was, however, no appreciable effect on thermal hyperalgesia or mechanical hyperalgesia. Treatment with a single dose of rofecoxib (10 mg/kg, PO, day 21 post surgery) or gabapentin (100mg/kg, PO, day 21 post surgery) significantly attenuated the change in HPWD, however, only gabapentin significantly decreased tactile allodynia. CONCLUSION: The rat medial meniscal tear (MMT) model mimics both nociceptive and neuropathic OA pain and is responsive to both a selective cylooxygenase-2 (COX-2) inhibitor commonly utilized for OA pain (rofecoxib) and a widely prescribed drug for neuropathic pain (gabapentin). The rat MMT model may therefore represent a predictive tool for the development of pharmacologic interventions for the treatment of the symptoms associated with OA.


Assuntos
Artralgia/patologia , Hiperalgesia/patologia , Osteoartrite do Joelho/patologia , Aminas/uso terapêutico , Analgésicos/uso terapêutico , Animais , Artralgia/tratamento farmacológico , Artralgia/etiologia , Ácidos Cicloexanocarboxílicos/uso terapêutico , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Modelos Animais de Doenças , Gabapentina , Membro Posterior , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Lactonas/uso terapêutico , Masculino , Osteoartrite do Joelho/complicações , Ratos , Sulfonas/uso terapêutico , Suporte de Carga/fisiologia , Ácido gama-Aminobutírico/uso terapêutico
7.
Osteoarthritis Cartilage ; 11(11): 821-30, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14609535

RESUMO

OBJECTIVE: To describe an in vivo model in the rat in which change in weight distribution is used as a measure of disease progression and efficacy of acetaminophen and two nonsteroidal anti-inflammatory drugs (NSAIDs) in a model of monosodium iodoacetate (MIA)-induced osteoarthritis (OA). METHODS: Intra-articular injections of MIA and saline were administered to male Wistar rats (175-200 g) into the right and left knee joints, respectively. Changes in hind paw weight distribution between the right (osteoarthritic) and left (contralateral control) limbs were utilized as an index of joint discomfort. Acetaminophen and two archetypal, orally administered NSAIDs, naproxen and rofecoxib, were examined for their ability to decrease MIA-induced change in weight distribution. RESULTS: A concentration-dependent increase in change in hind paw weight distribution was noted after intra-articular injection of MIA. Both naproxen and rofecoxib demonstrated the capacity to significantly (P<0.05) decrease hind paw weight distribution in a dose-dependent fashion, indicating that the change in weight distribution associated with MIA injection is susceptible to pharmacological intervention. CONCLUSION: The determination of differences in hind paw weight distribution in the rat MIA model of OA is a technically straightforward, reproducible method that is predictive of the effects of anti-inflammatory and analgesic agents. This system may be useful for the discovery of novel pharmacologic agents in human OA.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Experimental/fisiopatologia , Osteoartrite/fisiopatologia , Suporte de Carga , Acetaminofen/uso terapêutico , Analgésicos não Narcóticos/uso terapêutico , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Progressão da Doença , Relação Dose-Resposta a Droga , Membro Posterior/fisiopatologia , Iodoacetatos , Masculino , Osteoartrite/induzido quimicamente , Osteoartrite/tratamento farmacológico , Osteoartrite/patologia , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Resultado do Tratamento
8.
Biol Reprod ; 62(4): 879-85, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10727256

RESUMO

Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine produced by T cells and macrophages. A number of tissues also produce MIF during states of active differentiation and/or proliferation. The purpose of this study was to determine whether MIF is present in the corpus luteum (CL). The steady-state mRNA for MIF was examined in CL by Northern analysis on Day 5, Days 9-12, and Day 18 of the estrous cycle and at 0.5, 1, 4, 12, 24, and 36 h after a luteolytic injection of prostaglandin F(2alpha) (PGF(2alpha)) (n = 4 CL per time point). The greatest amount of MIF mRNA was observed in Day 5 CL compared with midcycle and Day 18 CL. Messenger RNA for MIF in CL collected 0.5 h post-PGF(2alpha) was greater than in midcycle and all other regressing CL. Immunohistochemical analysis (n = 4) revealed that MIF was present in the bovine CL throughout the estrous cycle and appeared to be localized to large luteal cells. It was concluded that MIF is produced within the bovine CL, mRNA expression is maximal in the early CL, and the protein is primarily localized to large luteal cells. The functional significance of MIF remains to be determined.


Assuntos
Corpo Lúteo/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , RNA Mensageiro/biossíntese , Animais , Northern Blotting , Western Blotting , Bovinos , Corpo Lúteo/citologia , Corpo Lúteo/crescimento & desenvolvimento , Dinoprosta/farmacologia , Estro/fisiologia , Feminino , Imuno-Histoquímica , Luteolíticos/farmacologia , Fatores Inibidores da Migração de Macrófagos/biossíntese , Fatores Inibidores da Migração de Macrófagos/genética , Progesterona/sangue
9.
Biol Reprod ; 56(5): 1175-80, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9160716

RESUMO

Macrophages within the corpus luteum are associated with spontaneous luteal regression in a number of species. However, an understanding of the consequences of macrophage recruitment on the functional capacity and responsiveness of the luteal tissue has remained elusive. Here we investigate the temporal appearance of macrophages and their potential impact in corpora lutea of rabbits, in which a rapid fall in progesterone synthesis and premature regression of the corpus luteum are initiated by withdrawal of the luteotropic hormone estradiol-17beta. Removal of estradiol implants, placed subcutaneously, induced a significant increase in the average number of macrophages per high-power field (hpf) in corpora lutea (p < 0.05) within 72 h. Replacement of the estradiol implants 48 h after their removal resulted in a marginal rebound of plasma progesterone and a variable number of luteal macrophages (range: 6-160 macrophages/hpf) among the 11 rabbits. A third experiment revealed that the relative numbers of macrophages within the corpora lutea have no apparent relationship to rates of progesterone synthesis in vitro: progesterone production (ng/mg tissue) did not differ (p > 0.05) between corpora lutea of estradiol-maintained rabbits and those of estradiol-replaced rabbits despite obvious differences in numbers of luteal macrophages (2 +/- 1 vs. 42 +/- 10 macrophages/hpf, respectively; p < 0.05). We conclude that the entry/recruitment of macrophages into the rabbit corpus luteum is sensitive to the luteotropic hormone estradiol-17beta and that the presence of macrophages does not preclude the continuation of progesterone production in surviving luteal tissue revitalized after estradiol removal/replacement.


Assuntos
Corpo Lúteo/citologia , Corpo Lúteo/efeitos dos fármacos , Estradiol/administração & dosagem , Macrófagos/efeitos dos fármacos , Animais , Movimento Celular/efeitos dos fármacos , Corpo Lúteo/metabolismo , Feminino , Luteólise/efeitos dos fármacos , Luteólise/fisiologia , Macrófagos/citologia , Progesterona/biossíntese , Pseudogravidez/metabolismo , Pseudogravidez/patologia , Coelhos
11.
Perit Dial Int ; 13 Suppl 2: S267-9, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8399585

RESUMO

Anemia, through a hyperkinetic state, is an important contributor to myocardial function impairment. To determine the cardiovascular effects of recombinant human erythropoietin (rHuEPO) therapy, 10 chronic peritoneal dialysis (CPD)-treated anemic children were studied before and during 18 months of treatment. The following parameters were recorded: hemoglobin (Hb) [percent of target level (TL) = x-2 standard deviations of normal Hb values for age and sex], heart rate (HR, beats/minute), mean arterial pressure (MAP, mmHg), end-diastolic left ventricular diameter (EDLVD, mm/sm BSA), shortening fraction (SF, percent), and interventricular septal thickness (IVS, mm/sm BSA). Student's t-test for paired data showed (vs time before treatment, T0) a progressive increase in Hb, a progressive decrease in HR, and a progressive increase in MAP. EDLVD progressively decreased, while SF and IVS remained unchanged throughout the study. Regression analysis showed a close correlation between anemia correction and decrease of HR (p < 0.01), while no correlation was found between Hb and EDLVD or SF, IVS, or MAP. Our data indicate that anemia correction in these patients is mainly associated with a decrease in hyperkinetic state (HR reduction with SF unvaried), while left ventricular function and dimensions remain normal, despite an increase in MAP.


Assuntos
Eritropoetina/uso terapêutico , Coração/fisiopatologia , Hemodinâmica , Diálise Peritoneal , Anemia/sangue , Anemia/etiologia , Anemia/fisiopatologia , Anemia/terapia , Pressão Sanguínea , Criança , Feminino , Frequência Cardíaca , Hemoglobinas/análise , Humanos , Falência Renal Crônica/complicações , Masculino , Contração Miocárdica , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Função Ventricular Esquerda
12.
Am J Nephrol ; 11(4): 271-5, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1799183

RESUMO

The effects of angiotensin II (AII) on proximal tubular reabsorption have been evaluated in 6 healthy volunteers under normal salt and water balance. One-hour clearance periods were performed before, during and after the infusion of pressor doses of AII; in 3 of the 6 subjects, the study was repeated with lower doses of AII. Glomerular filtration rate (GFR) and renal plasma flow (RPF) were determined by the clearances of inulin and PAH, and the fractional excretion of lithium (FELi) was considered as an index of proximal sodium reabsorption. The effects of AII on the fractional excretion of beta 2 microglobulin (FE beta 2M) were also studied. Both doses of AII decreased GFR and RPF and increased the filtration fraction (FF); the modifications of these parameters, as well as the reduction of FELi and the fractional excretion of sodium (FENa) and the increase of plasma aldosterone and of plasma atrial natriuretic peptide (ANP), were more evident with pressor doses of AII, which increased the blood pressure from 129/83 to 142/95 mm Hg (p less than 0.01). AII did not modify FE beta 2M in either study. During AII, FELi decreased less than FENa and both were closely and inversely related to the variations of FF, whilst no relationship was present between FE beta 2M and FF. These results suggest that, in normal humans, the AII-induced rise of FF may be an important factor, even if not the only one, in enhancing the proximal reabsorption of lithium and thus of sodium, whilst it does not affect the absorption of beta 2M.


Assuntos
Angiotensina II/fisiologia , Túbulos Renais Proximais/fisiologia , Adulto , Angiotensina II/farmacologia , Taxa de Filtração Glomerular/fisiologia , Humanos , Lítio/farmacocinética , Masculino , Natriurese/fisiologia , Circulação Renal/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Microglobulina beta-2/metabolismo
13.
J Cardiovasc Surg (Torino) ; 29(4): 476-9, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2971067

RESUMO

The influence of external compression on extra-anatomic bypass patency is still debated. The specific purpose of this study is the evaluation of ankle Pressure Index (P.I.) and Pulse Volume Recorder (P.V.R.) wave amplitude changes after 5 and 10 minutes of external bypass compression by body weight, lying on the side of the reconstruction. Eight patients with axillo-femoral bypass (mean follow-up 15.5 months) have been evaluated. The external body weight compression caused important changes of graft haemodynamics: (1) decrease in ankle Pressure Index at 5 min (p less than 0.005) or 10 min (p less than 0.0005); (2) decrease in P.V.R. wave amplitude at 5 min (p less than 0.005) and 10 min (p less than 0.025).


Assuntos
Artéria Axilar/cirurgia , Prótese Vascular , Peso Corporal , Artéria Femoral/cirurgia , Oclusão de Enxerto Vascular/etiologia , Perna (Membro)/irrigação sanguínea , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polietilenotereftalatos , Politetrafluoretileno , Pressão , Grau de Desobstrução Vascular
15.
Behring Inst Mitt ; (77): 82-7, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3002320

RESUMO

To study the nature of the antigen bridge between specific B and T lymphocytes we have isolated from the same donor clones of human T cells and EBV-transformed B cells specific for tetanus toxoid (TT). We found that TT-specific B cells are extremely efficient in presenting TT (but not an unrelated antigen) to T cells, as they can trigger T cell proliferation in the presence of only 10(-12) M TT, a concentration that is approximately 10(4) times lower than that required for presentation by conventional antigen-presenting cells such as macrophages or non-specific B cells. The high avidity of the interaction between specific B and T cells is reflected by the resistance to inhibition by antibodies against the T4 antigen. Experiments with fixed and chloroquine-treated B cells show that the role of surface antibodies is limited to the uptake of antigen and that in order to obtain presentation, the antigen has to be internalized, processed and subsequently displayed on the cell surface, where it becomes available for T cell recognition in an MHC-restricted fashion.


Assuntos
Linfócitos B/imunologia , Cooperação Linfocítica , Linfócitos T/imunologia , Células Apresentadoras de Antígenos/imunologia , Transformação Celular Viral , Antígenos HLA-DR , Herpesvirus Humano 4 , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Complexo Principal de Histocompatibilidade , Conformação Proteica , Receptores de Antígenos de Linfócitos B/imunologia , Toxoide Tetânico/imunologia
16.
Biochemistry ; 24(15): 4131-41, 1985 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-2413884

RESUMO

A panel of five monoclonal antibodies, designated U1-U5, produced by murine hybridoma clones has been raised to recombinant interferon (IFN) alpha-2, and one monoclonal antibody, designated U6, has been raised to a mixture of cyanogen bromide fragments of IFN alpha-2. These antibodies have been characterized with respect to (1) neutralization of IFN antiviral and antiproliferative activities, (2) binding to four cloned IFN alpha subtypes (alpha-1, alpha-2, alpha-4, and alpha-7) that are naturally occurring and to two novel products of recombinant DNA technology (delta-4 alpha-1 and delta-4 alpha-2/alpha-1 hybrid), and (3) binding to three cyanogen bromide fragments of IFN alpha-2. Four of the six monoclonal antibodies inhibited IFN antiviral activity. In conjunction with the previously reported monoclonal antibodies III/21 [Arnheiter, H., Thomas, R. M., Leist, T., Fountoulakis, M., & Gutte, B. (1981) Nature (London) 294, 278-280] and NK-2 [Secher, D. S., & Burke, D. C. (1980) Nature (London) 285, 446-450], eight unique epitopes have been described. Analysis of cross-reactivity patterns with IFN alpha fragments and subtypes indicated that monoclonal antibodies U1 and NK-2, which neutralized both antiviral and antiproliferative activities, and U2, which was nonneutralizing in these assays, were directed to distinct epitopes located in a polypeptide consisting of the amino-terminal 15 amino acid residues linked to residues 60-110 by a disulfide bond. The epitope recognized by U1 was determined to reside, at least in part, between residues 5 and 15. Competitive binding studies indicated that neutralizing monoclonal antibody U3, which did not bind to any of the cyanogen bromide fragments, was directed to an epitope partially overlapping that of NK-2. Epitopes to which neutralizing monoclonal antibodies U3, U4, and U5 and nonneutralizing antibody U6 were directed were readily distinguished by cross-reactivity with IFN alpha subtypes. The nonneutralizing monoclonal antibody U6 was determined to be directed to an epitope between residues 22 and 58. The fact that delta-4 alpha-1 and the delta-4 alpha-2/alpha-1 hybrid were active in an antiviral assay indicated a lack of direct functional significance for the first four amino-terminal amino acid residues and the Cys1-Cys98 disulfide bond. However, reduction with 2-mercaptoethanol of IFN alpha-2 altered the integrity of four of the eight epitopes. These data support a critical role for disulfide linkages in maintaining the native conformation of IFN alpha-2 and provide a potential basis for predicting the location of functionally important domains.


Assuntos
Anticorpos Monoclonais , Epitopos/análise , Interferon Tipo I/imunologia , Proteínas Recombinantes/imunologia , Aminoácidos/análise , Clonagem Molecular , Brometo de Cianogênio , Ensaio de Imunoadsorção Enzimática , Genes , Humanos , Interferon Tipo I/genética , Interferon Tipo I/farmacologia , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/imunologia , Plasmídeos , Vírus/efeitos dos fármacos
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