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1.
Indian J Otolaryngol Head Neck Surg ; 71(Suppl 1): 784-789, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31742064

RESUMO

High dose of radiation to bone may cause necrosis. Osteoradionecrosis of the cervical vertebrae is a rare adverse event of radiotherapy in patients treated for head and neck cancer. The risk on osteoradionecrosis will increase with doses exceeding 60 Gy. Minimal trauma of the overlying mucosa of the heavily irradiated cervical spine causes subsequent infections or instability may cause neck pain and severe neurological disability. In four patients the cervical spine received up to 100 Gy due to reirradiation. Clinically the patients presented with neck pain. All patients had defects in the pharyngeal posterior wall and cervical instability due to osteoradionecrosis of several cervical vertebrae. Despite optimal conservative treatment the patients developed sensory and motor function loss of the upper extremities. Laminectomies were performed and the cervical spine was stabilized. The pharyngeal posterior wall defects could not be reconstructed. All patients received lifelong antibiotic treatment. Pain and neurological deficits declined after surgery and initiating antibiotics. Eventually all patients could take up their daily activities. Three patients died between 6 months and 2 years after surgery. The cause of death was not related to the osteoradionecrosis. In case of cervical osteoradionecrosis, with secondary infections, stability of the spine should be restored even when the integrity of the pharyngeal posterior wall cannot be restored. Our cases demonstrate that even when an anterior approach is impossible, due to irradiation changed tissue structures of the pharyngeal posterior wall, a combination of lifelong antibiotic treatment and posterior stabilization is a good alternative. The vertebrae affected by osteoradionecrosis and secondary infection can be left in situ. This intervention leads to improvement in quality of life.

2.
Clin Otolaryngol ; 42(3): 693-700, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28032952

RESUMO

OBJECTIVE: Salvage surgery has a higher complication rate compared to primary surgical treatment. We evaluated clinical outcome of salvage neck dissections in relation to initial treatment modality, extent of surgery and patient-related factors. DESIGN: Single institution consecutive case series. SETTING: Tertiary Head and Neck Cancer Centre. PARTICIPANTS: In all, 87 patients with head and neck squamous cell carcinoma, who underwent salvage neck dissection after initial radiotherapy (n = 30), radiotherapy with carboplatin/5-fluorouracil (n = 43) or radiotherapy with cetuximab (n = 14). MAIN OUTCOME MEASURES: Incidence of complications, disease-specific survival. RESULTS: Complications occurred in 28% of the patients. Multivariate analysis identified extent of neck dissection as the only independent predictor of surgical complications (P = 0.010). Surgical complication rate was 16% after radiotherapy with systemic treatment, and 47% after radiotherapy alone (P = 0.171). The 5-year disease-specific survival was 55%, independent of complications, initial treatment, extent of surgery and patient-related factors. CONCLUSION: The only predictor for surgical complications was extent of surgery. Survival was not influenced by complications.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/terapia , Esvaziamento Cervical/métodos , Complicações Pós-Operatórias/epidemiologia , Terapia de Salvação , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/secundário , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/secundário , Humanos , Incidência , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Taxa de Sobrevida/tendências , Tomografia Computadorizada por Raios X
4.
Artigo em Inglês | MEDLINE | ID: mdl-25567545

RESUMO

This research focuses on the numerical simulation of stridor; a high pitched, abnormal noise, resulting from turbulent airflow and vibrating tissue through a partially obstructed airway. Characteristics of stridor noise are used by medical doctors as indication for location and size of the obstruction. The relation between type of stridor and the various diseases associated with airway obstruction is unclear; therefore, simply listening to stridor is an unreliable diagnostic tool. The overall aim of the study is to better understand the relationship between characteristics of stridor noise and localization and size of the obstruction. Acoustic analysis of stridor may then in future simplify the diagnostic process, and reduce the need for more invasive procedures such as laryngoscopy under general anesthesia. In this paper, the feasibility of a coupled flow, acoustic and structural model is investigated to predict the noise generated by the obstruction as well as the propagation of the noise through the airways, taking into account a one-way coupled fluid, structure, and acoustic interaction components. The flow and acoustic solver are validated on a diaphragm and a simplified airway model. A realistic airway model of a patient suffering from a subglottic stenosis, derived from a real computed tomography scan, is further analyzed. Near the mouth, the broadband noise levels at higher frequencies increased with approximately 15-20 dB comparing the stridorous model with the healthy model, indicating stridorous sound.


Assuntos
Acústica , Obstrução das Vias Respiratórias/patologia , Simulação por Computador , Obstrução das Vias Respiratórias/diagnóstico por imagem , Obstrução das Vias Respiratórias/fisiopatologia , Fenômenos Biomecânicos , Humanos , Cinética , Modelos Biológicos , Pressão , Reologia , Som , Tomografia Computadorizada por Raios X , Vibração
5.
Bioinspir Biomim ; 9(3): 036001, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24584155

RESUMO

The numerical simulation of an insect-sized 'X-wing' type biplane flapping wing configuration is performed in 3D using an immersed boundary method solver at Reynolds numbers equal to 1000 (1 k) and 5 k, based on the wing's root chord length. This X-wing type flapping configuration draws its inspiration from Delfly, a bio-inspired ornithopter MAV which has two pairs of wings flapping in anti-phase in a biplane configuration. The objective of the present investigation is to assess the aerodynamic performance when the original Delfly flapping wing micro-aerial vehicle (FMAV) is reduced to the size of an insect. Results show that the X-wing configuration gives more than twice the average thrust compared with only flapping the upper pair of wings of the X-wing. However, the X-wing's average thrust is only 40% that of the upper wing flapping at twice the stroke angle. Despite this, the increased stability which results from the smaller lift and moment variation of the X-wing configuration makes it more suited for sharp image capture and recognition. These advantages make the X-wing configuration an attractive alternative design for insect-sized FMAVS compared to the single wing configuration. In the Reynolds number comparison, the vorticity iso-surface plot at a Reynolds number of 5 k revealed smaller, finer vortical structures compared to the simulation at 1 k, due to vortices' breakup. In comparison, the force output difference is much smaller between Re = 1 k and 5 k. Increasing the body inclination angle generates a uniform leading edge vortex instead of a conical one along the wingspan, giving higher lift. Understanding the force variation as the body inclination angle increases will allow FMAV designers to optimize the thrust and lift ratio for higher efficiency under different operational requirements. Lastly, increasing the spanwise flexibility of the wings increases the thrust slightly but decreases the efficiency. The thrust result is similar to one of the spanwise studies, but the efficiency result contradicts it, indicating that other flapping parameters are involved as well. Results from this study provide a deeper understanding of the underlying aerodynamics of the X-wing type, which will help to improve the performance of insect-sized FMAVs using this unique configuration.


Assuntos
Aeronaves/instrumentação , Biomimética/instrumentação , Desenho Assistido por Computador , Voo Animal/fisiologia , Modelos Biológicos , Movimento/fisiologia , Asas de Animais/fisiologia , Algoritmos , Animais , Relógios Biológicos/fisiologia , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Análise Numérica Assistida por Computador , Oscilometria/métodos
6.
J Acoust Soc Am ; 128(4): 1668-78, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20968339

RESUMO

Cavity aeroacoustic noise is relevant for aerospace and automotive industries and widely investigated since the 1950s. Most investigations so far consider cavities where opening length and width are of similar scale. The present investigation focuses on a less investigated setup, namely cavities that resemble the door gaps of automobiles. These cavities are both slender (width much greater than length or depth) and partially covered. Furthermore they are under influence of a low Mach number flow with a relatively thick boundary layer. Under certain conditions, these gaps can produce tonal noise. The present investigation attempts to reveal the aeroacoustic mechanism of this tonal noise for higher resonance modes. Experiments have been conducted on a simplified geometry, where unsteady internal pressures have been measured at different spanwise locations. With increasing velocity, several resonance modes occur. In order to obtain higher mode shapes, the cavity acoustic response is simulated and compared with experiment. Using the frequency-filtered simulation pressure field, the higher modes shapes are retrieved. The mode shapes can be interpreted as the slender cavity self-organizing into separate Helmholtz resonators that interact with each other. Based on this, an analytical model is derived that shows good agreement with the simulations and experimental results.


Assuntos
Acústica , Automóveis , Modelos Teóricos , Ruído , Acústica/instrumentação , Simulação por Computador , Movimento (Física) , Análise Numérica Assistida por Computador , Pressão , Reprodutibilidade dos Testes , Espectrografia do Som , Fatores de Tempo , Transdutores de Pressão , Vibração
7.
Br J Ophthalmol ; 93(11): 1518-23, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19028743

RESUMO

AIM: To compare the outcome of various surgical approaches of orbital decompression in patients with Graves' orbitopathy (GO) receiving surgery for disfiguring proptosis. METHOD: Data forms and questionnaires from consecutive, euthyroid patients with inactive GO who had undergone orbital decompression for disfiguring proptosis in 11 European centres were analysed. RESULTS: Eighteen different (combinations of) approaches were used, the swinging eyelid approach being the most popular followed by the coronal and transconjunctival approaches. The average proptosis reduction for all decompressions was 5.0 (SD 2.1) mm. After three-wall decompression the proptosis reduction was significantly greater than after two-wall decompression. Additional fat removal resulted in greater proptosis reduction. Complications were rare, the most frequent being worsening of motility, occurring more frequently after coronal decompression. The average change in quality of life (QOL) in the appearance arm of the GO-QOL questionnaire was 20.5 (SD 24.8) points. CONCLUSIONS: In Europe, a wide range of surgical approaches is used to reduce disfiguring proptosis in patients with GO. The extent of proptosis reduction depends on the number of walls removed and whether or not fat is removed. Serious complications are infrequent. Worsening of ocular motility is still a major complication, but was rare in this series after the swinging eyelid approach.


Assuntos
Descompressão Cirúrgica/métodos , Oftalmopatia de Graves/cirurgia , Órbita/cirurgia , Adolescente , Adulto , Idoso , Descompressão Cirúrgica/efeitos adversos , Diplopia/etiologia , Feminino , Oftalmopatia de Graves/fisiopatologia , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento , Acuidade Visual/fisiologia , Adulto Jovem
8.
J Med Genet ; 42(7): 583-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15994880

RESUMO

BACKGROUND: A recent genetic study in mice and humans revealed the modulatory effect of MC1R (melanocortin-1 receptor) gene variants on kappa-opioid receptor mediated analgesia. It is unclear whether this gene affects basal pain sensitivity or the efficacy of analgesics acting at the more clinically relevant mu-opioid receptor. OBJECTIVE: To characterise sensitivity to pain and mu-opioid analgesia in mice and humans with non-functional melanocortin-1 receptors. METHODS: Comparisons of spontaneous mutant C57BL/6-Mc1r(e/e) mice to C57BL/6 wildtype mice, followed by a gene dosage study of pain and morphine-6-glucuronide (M6G) analgesia in humans with MC1R variants. RESULTS: C57BL/6-Mc1r(e/e) mutant mice and human redheads--both with non-functional MC1Rs--display reduced sensitivity to noxious stimuli and increased analgesic responsiveness to the mu-opioid selective morphine metabolite, M6G. In both species the differential analgesia is likely due to pharmacodynamic factors, as plasma levels of M6G are similar across genotype. CONCLUSIONS: Genotype at MC1R similarly affects pain sensitivity and M6G analgesia in mice and humans. These findings confirm the utility of cross species translational strategies in pharmacogenetics.


Assuntos
Analgesia , Variação Genética , Dor/genética , Receptor Tipo 1 de Melanocortina/genética , Receptores Opioides mu/efeitos dos fármacos , Adolescente , Adulto , Analgésicos Opioides/farmacocinética , Analgésicos Opioides/uso terapêutico , Animais , Relação Dose-Resposta a Droga , Feminino , Genótipo , Cor de Cabelo/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Morfina/farmacocinética , Morfina/uso terapêutico , Derivados da Morfina/farmacocinética , Derivados da Morfina/uso terapêutico , Dor/tratamento farmacológico , Medição da Dor/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , Valores de Referência
9.
Br J Anaesth ; 94(6): 825-34, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15833777

RESUMO

BACKGROUND: There is evidence from animal studies suggesting the existence of a ceiling effect for buprenorphine-induced respiratory depression. To study whether an apparent ceiling effect exists for respiratory depression induced by buprenorphine, we compared the respiratory effects of buprenorphine and fentanyl in humans and rats. METHODS: In healthy volunteers, the opioids were infused i.v. over 90 s and measurements of minute ventilation at a fixed end-tidal PCO2 of 7 kPa were obtained for 7 h. Buprenorphine doses were 0.7, 1.4, 4.3 and 8.6 microg kg(-1) (n=20 subjects) and fentanyl doses 1.1, 2.1, 2.9, 4.3 and 7.1 microg kg(-1) (n=21). Seven subjects received placebo. In rats, both opioids were infused i.v. over 20 min, and arterial PCO2 was measured 5, 10, 15 and 20 min after the start of fentanyl infusion and 30, 150, 270 and 390 min after the start of buprenorphine infusion. Doses tested were buprenorphine 0, 100, 300, 1000 and 3000 microg kg(-1) and fentanyl 0, 50, 68 and 90 microg kg(-1). RESULTS: In humans, fentanyl produced a dose-dependent depression of minute ventilation with apnoea at doses > or = 2.9 microg kg(-1); buprenorphine caused depression of minute ventilation which levelled off at doses > or = 3.0 microg kg(-1) to about 50% of baseline. In rats, the relationship of arterial PCO2 and fentanyl dose was linear, with maximum respiratory depression at 20 min (maximum PaCO2 8.0 kPa). Irrespective of the time at which measurements were obtained, buprenorphine showed a non-linear effect on PaCO2, with a ceiling effect at doses > 1.4 microg kg(-1). The effect on PaCO2 was modest (maximum value measured, 5.5 kPa). CONCLUSIONS: Our data confirm a ceiling effect of buprenorphine but not fentanyl with respect to respiratory depression.


Assuntos
Analgésicos Opioides/efeitos adversos , Buprenorfina/efeitos adversos , Fentanila/efeitos adversos , Insuficiência Respiratória/induzido quimicamente , Adulto , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/toxicidade , Animais , Buprenorfina/administração & dosagem , Buprenorfina/toxicidade , Dióxido de Carbono/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Fentanila/administração & dosagem , Fentanila/toxicidade , Humanos , Masculino , Pressão Parcial , Ratos , Ratos Wistar
10.
Acta Chir Belg ; 104(6): 719-23, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15663282

RESUMO

The rarity of Spigelian hernias and the frequent subtle clinical findings can cause an important delay in diagnosis, especially in obese patients. Furthermore it has a high risk of incarceration. When this occurs, a fast recognition and adequate treatment are necessary. Treatment can be primary suture or mesh repair. More recently, the laparoscopic approach has become more popular. We present two cases of incarcerated Spigelian hernia and we give a review of the literature, with specific attention for the anatomical features and pathogenesis.


Assuntos
Hérnia Ventral/diagnóstico , Hérnia Ventral/cirurgia , Feminino , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Implantação de Prótese , Telas Cirúrgicas , Procedimentos Cirúrgicos Operatórios/métodos
11.
J Biomech Eng ; 125(3): 355-62, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12929240

RESUMO

A new one-dimensional model is presented for the calculation of steady and unsteady flow through an indented two-dimensional channel with separation and reattachment. It is based on an interactive boundary layer approach, where the equations for the boundary layer flow near the channel walls and for an inviscid core flow are solved simultaneously. This approach requires no semi-empirical inputs, such as the location of separation and reattachment, which is an advantage over other existing one-dimensional models. Because of the need of an inviscid core alongside the boundary layers, the type of inflow as well as the length of the channel and the value of the Reynolds number poses some limitations on the use of the new model. Results have been obtained for steady flow through the indented channel of Ikeda and Matsuzaki. In further perspective, it is discussed how the present model, in contrast to other one-dimensional flow models, can be extended to calculate the flow in nonsymmetrical channels, by considering different boundary layers on each of the walls.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Fenômenos Fisiológicos Sanguíneos , Hemorreologia/métodos , Modelos Cardiovasculares , Dinâmica não Linear , Simulação por Computador , Viscosidade
12.
J Clin Pathol ; 55(5): 359-66, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11986342

RESUMO

AIM: To investigate whether multiparameter flow cytometry (MP-FCM) can be used for the detection of micrometastasis in sentinel lymph nodes (SLNs) in breast cancer. METHODS: Formalin fixed, paraffin wax embedded sentinel lymph nodes (n = 238) from 98 patients were analysed. For each lymph node, sections for haematoxylin and eosin (H&E) staining and immunohistochemistry (IHC) for cytokeratin (MNF116) were cut at three levels with a distance of 500 microm. The intervening material was used for MP-FCM. Cells were immunostained with MNF116, followed by an incubation with fluorescein isothiocyanate (FITC) labelled goat antimouse immunoglobulin. DNA was stained using propidium iodide. From each lymph node 100,000 cells were analysed on the flow cytometer. RESULTS: Thirty eight of the 98 patients with breast carcinoma showed evidence of metastatic disease in the SLN by one ore more of the three methods. In 37 of 38 cases where metastatic cells were seen in the routine H&E and/or IHC, more than 1% cytokeratin positive cells were detected by MP-FCM. In 24 patients, metastatic foci were more than 2 mm (macrometastasis) and in 14 these foci were smaller than 2 mm (micrometastasis). In three of these 14 cases, MP-FCM revealed positive SLNs, although this was not seen at first glance in the H&E or IHC sections. After revision of the slides, one of these three remained negative. However, MP-FCM analysis of the cytokeratin positive cells showed an aneuploid DNA peak, which was almost identical to that of the primary breast tumour. Duplicate measurements, done in 41 cases, showed a 99% reproducibility. In five of 14 patients with micrometastasis, one or two metastatic foci were found in the non-SLN. However, in 15 of 24 macrometastases multiple non-SLNs were found to have metastatic tumour. All micrometastases except for the remaining negative one mentioned above showed only diploid tumour cells, despite the fact that their primary tumours contained both diploid and aneuploid tumour cells. In primary tumours with more than 60% aneuploid cells, predominantly aneuploid macrometastasis were found, whereas diploid primary tumours only showed diploid micrometastases or macrometastases in their SLN. Aneuploid SLN macrometastases were associated with non-SLN metastases in five of seven patients, whereas diploid cases showed additional non-SLN metastases in only seven of 16 patients. CONCLUSION: In all cases, MP-FCM was sufficient to detect micrometastatic tumour cells in a large volume of lymph node tissue from SLNs. In some cases it was superior to H&E and IHC staining. Approximately 30% of SLN micrometastases are accompanied by additional non-SLN metastases. The size of the aneuploid fraction (> 60%) in the primary tumour may influence the risk of having both SLN and non-SLN metastases.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/secundário , Carcinoma Lobular/secundário , Biópsia de Linfonodo Sentinela/métodos , Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , DNA de Neoplasias/análise , Feminino , Citometria de Fluxo/métodos , Humanos , Imuno-Histoquímica/métodos , Metástase Linfática/patologia , Ploidias , Sensibilidade e Especificidade , Coloração e Rotulagem/métodos
13.
Phys Med Biol ; 46(11): 2857-71, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11720351

RESUMO

Techniques for high precision irradiation experiments with protons, to investigate the volume dependence of the tolerance dose of the rat cervical spinal cord are described. In the present study, 50% of the lateral cross section of the spinal cord was irradiated. The diameter of the cross section of this part of the rat spinal cord is at maximum 3.5 mm. Therefore, a dedicated procedure was developed to comply with the needs for a very high positioning accuracy and high spatial resolution dosimetry. By using 150 MeV protons a steep dose gradient (20-80% = 1 mm) in the centre of the spinal cord was achieved. This yields a good dose contrast between the left and right halves of the cord. A home-made digital x-ray imager with a pixel resolution of 0.18 mm/pixel was used for position verification of the spinal cord. A positioning accuracy of 0.09 mm was obtained by using information of multiple pixels. The average position stability during the irradiation was found to be 0.08 mm (1 SD) without significant systematic deviations. Profiles of the dose distribution were measured with a 2D dosimetry system consisting of a scintillating screen and a CCD camera. Dose volume histograms of the whole spinal cord as well as separately of the white and grey matters were calculated using MRI imaging of the cross section of the rat cervical spinal cord. From the irradiation of 20 animals a dose-response curve has been established. MRI showed radiation-induced damage at the high dose side of the spinal cord. Analysis of the preliminary dose-response data shows a significant dose-volume effect. With the described procedure and equipment it is possible to perform high precision irradiations on selected parts of the spinal cord.


Assuntos
Física Nuclear/métodos , Prótons , Medula Espinal/patologia , Medula Espinal/efeitos da radiação , Animais , Ciclotrons/instrumentação , Relação Dose-Resposta à Radiação , Radioisótopos de Irídio/uso terapêutico , Imageamento por Ressonância Magnética , Modelos Estatísticos , Radiometria/métodos , Ratos , Raios X
14.
Trop Med Int Health ; 5(10): 692-5, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11044263

RESUMO

BACKGROUND: Chloroquine (CQ) and Sulfadoxine-Pyrimethamine (SP) are the predominantly used antimalarials in Zambia and other parts of East Africa, but increasing resistance of P. falciparum is a major concern. METHODS: Seventy consecutive patients with uncomplicated falciparum malaria were enrolled. In 43 patients, no prior CQ use could be demonstrated by history and urianalysis (qualitative test, Dill & Glazko) and these patients were given CQ; the other 27 had taken CQ before and received SP. RESULTS: Combined R-II and R-III CQ-resistance was 58% (60% in under-fives), which is the range previously reported from Zambia. By contrast, SP-resistance (R-II and R-III) was much higher (26%) than previously reported (3% - 17%). The history of prior CQ intake correlated well with the results of the Dill-Glazko test; there was no evidence for prior SP intake to explain these results. CONCLUSION: If our findings of SP resistance are confirmed, other drugs such as quinine, atovaquone/proguanil and artemisinin are required to treat malaria in Zambia.


Assuntos
Antimaláricos/farmacologia , Cloroquina/farmacologia , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Pirimetamina/farmacologia , Sulfadoxina/farmacologia , Animais , Antimaláricos/uso terapêutico , Pré-Escolar , Cloroquina/uso terapêutico , Combinação de Medicamentos , Resistência a Medicamentos , Feminino , Seguimentos , Humanos , Lactente , Masculino , Projetos Piloto , Plasmodium falciparum/crescimento & desenvolvimento , Pirimetamina/uso terapêutico , Saúde da População Rural , Sulfadoxina/uso terapêutico , Zâmbia
15.
Gut ; 40(3): 320-7, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9135519

RESUMO

BACKGROUND: T cells play an important part in Crohn's disease. Immunomodulating therapies that target T cell activation may have clinical effects in Crohn's disease. AIM: To investigate the toxicity and potential efficacy of anti-CD4 monoclonal antibody therapy in patients with Crohn's disease. PATIENTS AND METHODS: A dose escalating pilot study was conducted in three groups of four patients with intractable Crohn's disease, refractory to steroids. They received 70, 210, or 700 mg of cM-T412, a depleting anti-CD4 monoclonal antibody (mAb). RESULTS: The mean reduction in Crohn's disease activity index (CDAI) was respectively 25%, 24%, and 36% at four weeks, and 24% and 52% at 10 weeks in the 210 mg and 700 mg groups. There was only a minor effect on endoscopically evaluated disease activity. Side effects were mild to moderate fever with chills and headache. No signs of opportunistic infection were seen. There was a sustained decrease in CD4 count which lasted at least four weeks in the 70 mg group (76.3 (SD 40.6)% of the baseline value), and 10 weeks in both the 210 mg group (80.8 (SD 60.9)%) and the 700 mg group (24.8 (SD 15.4)%). The primary and secondary humoral immune response was not influenced by anti-CD4 mAb treatment. CONCLUSION: This study shows the moderate potential efficacy of treatment of patients with Crohn's disease using a depleting chimeric monoclonal anti-CD4 antibody.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antígenos CD4/imunologia , Doença de Crohn/terapia , Imunossupressores/administração & dosagem , Doença Aguda , Adulto , Idoso , Anticorpos Monoclonais/uso terapêutico , Formação de Anticorpos , Colonoscopia , Doença de Crohn/imunologia , Doença de Crohn/patologia , Esquema de Medicação , Feminino , Seguimentos , Humanos , Imunofenotipagem , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Receptores do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
16.
Radiology ; 201(1): 93-6, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8816527

RESUMO

PURPOSE: To evaluate the findings from magnetic resonance (MR) imaging of the cervical spine and brain after acute whiplash injury. MATERIALS AND METHODS: Within 3 weeks of trauma, 100 patients underwent MR imaging for evaluation of the cervical spine and the brain. In addition, plain radiographs were obtained, including functional images of the cervical spine. RESULTS: Only one patient had an abnormality on the MR image that was related to trauma (ie, prevertebral edema). In 17 patients, functional images showed a kyphotic angle, but no evidence of soft-tissue injury was seen on MR images. CONCLUSION: There is no role for MR imaging in the routine work-up of patients with acute whiplash injury who have normal plain radiographic findings and no evidence of a neurologic deficit. A kyphotic angle seen on functional images of the cervical spine should not be assumed to indicate soft-tissue injury and is most likely attributable to a compensating mechanism of hypermobility at a level of the spine above that at which hypomobility occurs, which is probably the result of a muscle spasm.


Assuntos
Lesões Encefálicas/diagnóstico , Imageamento por Ressonância Magnética , Traumatismos em Chicotada/diagnóstico , Doença Aguda , Adulto , Encéfalo/patologia , Vértebras Cervicais/patologia , Estudos de Avaliação como Assunto , Feminino , Humanos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino , Estudos Prospectivos , Lesões dos Tecidos Moles/diagnóstico
17.
Gastroenterology ; 109(1): 129-35, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7797011

RESUMO

BACKGROUND & AIMS: Increased concentrations of tumor necrosis factor (TNF), a potent proinflammatory cytokine, can be shown in the mucosa of patients with active Crohn's disease. Neutralization of TNF has been shown to decrease recruitment of inflammatory cells and granuloma formation in several animal models. The aim of this study was to investigate the safety and potential efficacy of an anti-TNF monoclonal antibody in the treatment of active Crohn's disease. METHODS: Ten patients with active Crohn's disease that was unresponsive to therapy were administered a single infusion of an anti-TNF human/mouse chimeric monoclonal antibody (cA2) in an open-label treatment protocol while the baseline anti-inflammatory therapy was continued. RESULTS: Eight patients showed normalization of Crohn's Disease Activity Index scores and healing of ulcerations as judged by colonoscopy within 4 weeks after treatment. One patient had a perforation after colonoscopy and recovered completely after surgery. One elderly patient showed a poor response. The average duration of response after a single infusion was 4 months. No adverse experiences related to cA2 were observed. CONCLUSIONS: The results support the hypothesis that TNF is of major importance in the pathogenesis of Crohn's disease. Treatment with cA2 was safe and may be useful in patients with Crohn's disease that is unresponsive to steroid treatment.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Doença de Crohn/terapia , Fator de Necrose Tumoral alfa/imunologia , Adulto , Análise de Variância , Animais , Sedimentação Sanguínea , Proteína C-Reativa/metabolismo , Clonagem Molecular , Colo/patologia , Doença de Crohn/sangue , Doença de Crohn/patologia , Feminino , Humanos , Infliximab , Interleucina-6/sangue , Masculino , Camundongos , Pessoa de Meia-Idade , Receptores do Fator de Necrose Tumoral/metabolismo , Proteínas Recombinantes de Fusão/uso terapêutico , Recidiva , Indução de Remissão
18.
Inflamm Bowel Dis ; 1(3): 193-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-23282389

RESUMO

: Mucosal cells from patients with Crohn's disease regularly express HLA-class II antigens, which are thought to be induced by cytokines, in particular interferon gamma, that are secreted by activated T-cells. Abberant MHC-class II expression by epithelial cells may play a role in diseases characterized by T-cell activation. Activated CD4-positive T-cells are present in the lamina propria of patients with Crohn's disease. In this study we report the results of an open label, single center anti-CD4 ~ trial in patients with steroid refractory Crohn's disease. A rapid and near complete loss of HLA-DR expression by mucosal cells was observed in 10 out of 12 patients, following infusion of the chimeric anti-CD4 antibody M-T412. These results suggest that CD4-positive T-cells are necessary for epithelial class II expression in patients with Crohn's disease.

19.
Lancet ; 344(8930): 1105-10, 1994 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-7934491

RESUMO

Tumour necrosis factor alpha (TNF alpha) is a critical inflammatory mediator in rheumatoid arthritis, and may therefore be a useful target for specific immunotherapy. In support of this hypothesis, we previously observed beneficial responses in patients with active rheumatoid arthritis after open-label administration of a chimeric monoclonal antibody to TNF alpha (cA2). We now report the results of a four-centre, randomised double-blind trial of a single infusion of 1 or 10 mg/kg cA2 compared with placebo in 73 patients with active rheumatoid arthritis. The primary endpoint of the study was the achievement at week 4 of a Paulus 20% response, an amalgam of six clinical, observational, and laboratory variables. Intention-to-treat analysis of data from individual patients showed only 2 of 24 placebo recipients responding at this time, compared with 11 of 25 patients treated with low-dose cA2 (p = 0.0083) and 19 of 24 patients treated with high-dose cA2 (p < 0.0001). Over half of the high-dose cA2 patients responded by the more stringent 50% Paulus criteria at this time (p = 0.0005). The magnitude of these responses was impressive, with maximum mean improvements in individual disease-activity assessments, such as tender or swollen-joint counts and in serum C-reactive protein, exceeding 60% for patients on high-dose treatment. There were two severe adverse events. 1 patient on 1 mg/kg cA2 developed pneumonia ("possibly" treatment-related) and 1 on 10 mg/kg had a fracture ("probably not" treatment-related). The results provide the first good evidence that specific cytokine blockade can be effective in human inflammatory disease and define a new direction for the treatment of rheumatoid arthritis.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Artrite Reumatoide/terapia , Fator de Necrose Tumoral alfa/imunologia , Adolescente , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Antirreumáticos/uso terapêutico , Artrite Reumatoide/patologia , Relação Dose-Resposta Imunológica , Método Duplo-Cego , Feminino , Humanos , Infliximab , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Medição da Dor , Placebos
20.
Lancet ; 344(8930): 1125-7, 1994 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-7934495

RESUMO

Our in-vitro, animal, and early clinical data suggest that tumour necrosis factor alpha (TNF alpha) is an important target for specific biological therapy in rheumatoid arthritis. We report the results of repeated treatment with a chimeric monoclonal antibody to TNF alpha (cA2) in patients having disease flares. 7 patients originally enrolled in an open-label trial completed two to four cycles, each of which was followed by a good clinical response, with median improvements in the swollen-joint count and C-reactive protein exceeding 80%. cA2 may be useful therapy in the control of acute disease flares in rheumatoid arthritis and treatment programmes including cA2 may be effective in the long-term management of this disease.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Artrite Reumatoide/terapia , Fator de Necrose Tumoral alfa/imunologia , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Proteína C-Reativa/análise , Relação Dose-Resposta Imunológica , Humanos , Infliximab , Infusões Intravenosas , Recidiva
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