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1.
Sci Rep ; 12(1): 8624, 2022 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-35597810

RESUMO

The human luteinising hormone choriogonadotropin receptor (LHCGR) is a G-protein coupled receptor activated by both human chorionic gonadotropin (hCG) and luteinizing hormone (LH), two structurally related gonadotropins with essential roles in ovulation and maintenance of the corpus luteum. LHCGR expression predominates in ovarian tissues where it elicits functional responses through cyclic adenosine mononucleotide (cAMP), Ca2+ and extracellular signal-regulated kinase (ERK) signalling. LHCGR expression has also been localized to the human endometrium, with purported roles in decidualization and implantation. However, these observations are contentious. In this investigation, transcripts encoding LHCGR were undetectable in bulk RNA sequencing datasets from whole cycling endometrial tissue and cultured human endometrial stromal cells (EnSC). However, analysis of single-cell RNA sequencing data revealed cell-to-cell transcriptional heterogeneity, and we identified a small subpopulation of stromal cells with detectable LHCGR transcripts. In HEK-293 cells expressing recombinant LHCGR, both hCG and LH elicited robust cAMP, Ca2+ and ERK signals that were absent in wild-type HEK-293 cells. However, none of these responses were recapitulated in primary EnSC cultures. In addition, proliferation, viability and decidual transformation of EnSC were refractory to both hCG and LH, irrespective of treatment to induce differentiation. Although we challenge the assertion that LHCGR is expressed at a functionally active level in the human endometrium, the discovery of a discrete subpopulation of EnSC that express LHCGR transcripts may plausibly account for the conflicting evidence in the literature.


Assuntos
Receptores do LH , Células Estromais , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Células HEK293 , Humanos , Receptores Acoplados a Proteínas G , Receptores do LH/genética , Receptores do LH/metabolismo , Células Estromais/metabolismo
2.
Br J Dermatol ; 168(5): 968-76, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23278330

RESUMO

BACKGROUND: Skin ageing is influenced by environmental factors such as ultraviolet (UV) radiation. The effects of UV radiation on skin functions should be investigated using human in vitro models to understand the mechanisms of skin ageing. Additionally, marine algae provide a valuable source for identifying and extracting biologically active substances. OBJECTIVES: In this study, sargachromanol E was isolated from a marine brown alga, Sargassum horneri, and its inhibitory effect on skin ageing was investigated using UVA-irradiated dermal fibroblasts. METHODS: Formation of intracellular reactive oxygen species (ROS), lipid peroxidation and protein oxidation induced by UVA irradiation were investigated in UVA-irradiated human dermal fibroblasts. The levels of matrix metalloproteinases (MMPs) were determined by reverse-transcriptase polymerase chain reaction and Western blot analysis. RESULTS: Sargachromanol E did not exhibit any significant cytotoxicity or phototoxicity in UVA-exposed dermal fibroblasts. Additionally, sargachromanol E suppressed intracellular formation of ROS, membrane protein oxidation, lipid peroxidation and expression of collagenases such as MMP-1, MMP-2 and MMP-9, all of which are caused by UVA exposure. It was further found that these inhibitions were related to an increase in the expression of the tissue inhibitor of metalloproteinase (TIMP) genes, TIMP1 and TIMP2. Moreover, we have shown that the transcriptional activation of activator protein 1 (AP-1) signalling caused by UVA irradiation was inhibited by treatment with sargachromanol E. CONCLUSIONS: This study suggests that UVA irradiation modulates MMP expression via the transcriptional activation of AP-1 signalling, whereas treatment with sargachromanol E protected cell damage caused by UVA irradiation.


Assuntos
Benzopiranos/metabolismo , Fibroblastos/efeitos dos fármacos , Protetores contra Radiação/farmacologia , Sargassum/química , Envelhecimento da Pele/efeitos dos fármacos , Benzopiranos/farmacologia , Western Blotting , Células Cultivadas/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 2 da Matriz/genética , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/efeitos da radiação , Envelhecimento da Pele/efeitos da radiação , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Inibidores Teciduais de Metaloproteinases/metabolismo , Raios Ultravioleta/efeitos adversos
3.
Plant Dis ; 94(11): 1373, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30743631

RESUMO

In May 2008, symptoms of blueberry blight were observed on half-high blueberry (Vaccinium corymbosum L.) in a plant nursery in Anning, Yunnan Province. Symptoms included dieback and bud and branch blight. Symptomatic plant samples were washed with running tap water, disinfected with 2% sodium hypochlorite and then 70% alcohol, rinsed in sterile distilled water, plated on potato dextrose agar (PDA), and incubated at 26°C. Conidia forming on PDA were hyaline, granular, fusoid to ellipsoid, widest in the upper third with an obtuse apex and flattened, subtruncate base, and 18 to 21 × 4.5 to 8 µm. The pathogen was also identified to the species level by sequencing the ribosomal internal transcribed spacer regions 1 and 2 (ITSI-5.8S-ITS2) and the translation elongation factor 1-alpha (EF1-α). BLAST searches at GenBank showed the highest nucleotide sequence identity with Neofusicoccum vitifusiforme reference sequence (ITS: >98%, EF638785; EF1-α: 100%, EF638744 and AY343343). Representative sequences of isolates from both regions were deposited in GenBank (ITS: Accession No. HM131604; EF1-α: Accession No. HM454277). Pathogenicity tests were conducted on 2-year-old blueberry seedlings (half-high blueberry). Mycelial plugs (3 mm in diameter) of N. vitifusiforme from actively growing colonies (PDA) were applied to same-size bark wounds in the center of the stems. Inoculation wounds were wrapped with Parafilm. Control seedlings received sterile PDA plugs. Inoculated and control seedlings (five each) were kept in a greenhouse and watered as needed. After 2 weeks, all of the inoculated but none of the control blueberry seedlings showed dark vascular stem tissue. N. vitifusiforme was reisolated from symptomatic tissues, thus fulfilling Koch's postulates. N. vitifusiforme has been reported as a pathogen of olive (2), plum, peach (1), and grapevine (3). To our knowledge, this is the first report of N. vitifusiforme on blueberry in China as well as worldwide. References: (1) U. Damm et al. Mycologia 99:664, 2007. (2) C. Lazzizera et al. Plant Pathol. 57:948, 2008. (3) J. M. van Niekerk et al. Mycologia 96:781, 2004.

4.
Singapore Med J ; 46(7): 347-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15968448

RESUMO

We report a 67-year-old woman who underwent laparoscopic-assisted abdomino-perineal resection for rectal carcinoma. She sustained hypotension of 40/20 mmHg associated with bradycardia (heart rate 30 to 45 beats per minute) and an end-tidal carbon dioxide level of zero when she was raised to a head-up position at the end of surgery to facilitate pelvic irrigation. Pulmonary air embolism was confirmed by aspiration of 15 millilitres of foamy blood from her central venous line. Resuscitation was successful and she recovered completely with no neurological deficits.


Assuntos
Embolia Aérea/terapia , Complicações Intraoperatórias/terapia , Ressuscitação , Idoso , Dióxido de Carbono , Embolia Aérea/etiologia , Feminino , Humanos , Laparoscopia , Postura , Neoplasias Retais/cirurgia
5.
Anaesth Intensive Care ; 33(6): 739-43, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16398378

RESUMO

In a single-blind randomized trial, three types of laryngeal masks: the reusable LMA Classic, the single-use LMA Unique and SoftSeal were inserted by novice medical officers in anaesthesia. Five successive attempts were undertaken with each mask type. The order of the mask type insertion was randomly selected. Mean (SD) insertion times for LMA Classic, LMA Unique and Soft Seal were 32.9 (12.3), 39.6 (23.4) and 49.4 (50.4) seconds respectively. Differences were only significant between LMA Classic and SoftSeal (P=0.012). There were no significant differences in first attempt success rates (LMA Classic 80%, LMA Unique 77% and SoftSeal 62%). The SoftSeal was most frequently associated with blood on the mask (32%) compared to the LMA Unique (9%) and LMA Classic (6%). Sore throat was experienced in 14% of patients in the LMA Unique group versus 41% and 42% in the LMA Classic and SoftSeal groups respectively. Mean +/- SD oropharyngeal leak pressure was significantly higher in the SoftSeal (21+/-6 cmH2O) compared to the LMA Classic (17+/-7 cmH2O) and LMA Unique (16+/-6 cmH2O). Novice medical doctors can be taught to insert disposable laryngeal masks. The SoftSeal took longer to insert, which resulted in a higher incidence of blood on the mask, but success rates did not differ The LMA Unique was associated with the lowest incidence of sore throat in the immediate postoperative period. A higher oropharyngeal leak pressure with the SoftSeal may indicate improved airway seal and protection against aspiration.


Assuntos
Anestesia por Inalação/instrumentação , Equipamentos Descartáveis , Reutilização de Equipamento , Máscaras Laríngeas , Adolescente , Adulto , Idoso , Pessoal Técnico de Saúde , Análise de Variância , Distribuição de Qui-Quadrado , Competência Clínica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Probabilidade , Valores de Referência , Ressuscitação/educação , Fatores de Risco , Método Simples-Cego
6.
Emerg Med J ; 19(4): 292-4, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12101133

RESUMO

OBJECTIVE: To compare the ease of use of the direct vision laryngoscope and the lighted stylet (Trachlight) by novice staff. METHODS: Ten novice medical officers (MOs) performed orotracheal intubations using either the conventional direct vision laryngoscope (DL) or a lighted stylet device (Trachlight). They performed their DL intubations during the first phase of the study, followed by the Trachlight intubations in the subsequent phase. RESULTS: 51 of 54 (94%) of the DL intubation attempts were successful compared with 36 of 54 (67%) of the Trachlight intubations (p<0.001). The mean (SEM) time for intubation was 44 (7) seconds in the DL group and 66 (13) seconds in the Trachlight group (p=0.004). In addition 45 of 54 (83%) of the DL intubations were successful at the first attempt versus 15 of 54 (28%) in the Trachlight group (p<0.001). CONCLUSION: The results show that the use of the conventional direct vision laryngoscope in novices is associated with significantly shorter mean intubation times and higher success rates on the first attempt compared with the Trachlight.


Assuntos
Intubação Intratraqueal/instrumentação , Laringoscopia , Adolescente , Adulto , Idoso , Feminino , Humanos , Iluminação , Masculino , Corpo Clínico Hospitalar , Pessoa de Meia-Idade
7.
Am J Surg Pathol ; 24(11): 1558-62, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11075860

RESUMO

We report an epithelioid trophoblastic tumor (ETT), a recently delineated type of gestational trophoblastic tumor (GTT), discovered in the uterus of a 66-year-old woman. She had been treated for a hydatidiform mole 17 years previously without chemotherapy. The resected uterus contained a solid/cystic tumor located entirely within the myometrium. Microscopically, there was an epithelial-like growth pattern. The tumor was circumscribed, with a pushing border, and the tumor cells grew in cords, nests, and sheets within which were aggregates of hyaline material and necrotic debris. Most tumor cells were mononuclear and had an epithelioid appearance with distinct cell borders, eosinophilic cytoplasm, and nuclei with occasional indistinct nucleoli. Scattered multinucleated cells consistent with syncytiotrophoblastic cells were also present. Immunohistochemical staining revealed strong diffuse reactivity for cytokeratins (CK7, AE1/AE3, CAM 5.2, CK18) and epidermal growth factor receptor, and focal reactivity, mainly in syncytiotrophoblastic cells, for beta-human chorionic gonadotropin, human placental lactogen, and inhibin-alpha. The histologic and immunohistochemical features were characteristic of ETT, and helped to distinguish the tumor from other trophoblastic tumors and squamous cell carcinoma. An unusual observation was a high mitotic count, reflected in a Ki-67 proliferative index of 68.6%. Our findings indicate that ETT, like other types of GTT, can occur in postmenopausal women, even years after a gestational event.


Assuntos
Células Epitelioides/patologia , Pós-Menopausa , Tumor Trofoblástico de Localização Placentária/patologia , Neoplasias Uterinas/patologia , Idoso , Biomarcadores Tumorais/análise , Células Epitelioides/química , Feminino , Humanos , Imuno-Histoquímica , Proteínas de Neoplasias/análise , Gravidez , Tomografia Computadorizada por Raios X , Tumor Trofoblástico de Localização Placentária/química , Tumor Trofoblástico de Localização Placentária/diagnóstico por imagem , Tumor Trofoblástico de Localização Placentária/cirurgia , Neoplasias Uterinas/química , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/cirurgia
8.
Acta Cytol ; 44(2): 218-22, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10740609

RESUMO

OBJECTIVE: To determine the patterns of CD34 reactivity in hepatocellular adenoma and focal nodular hyperplasia and to evaluate the utility of CD34 reactivity in the diagnosis of hepatocellular carcinoma. STUDY DESIGN: Seventeen cases of well-differentiated hepatocellular carcinoma, 14 cases of cirrhosis, 9 cases of focal nodular hyperplasia and 7 cases of hepatocellular adenoma were stained with immunoperoxidase antibodies to CD34. The slides were scored according to the degree of lesional reactivity. RESULTS: Fourteen of 17 cell blocks with hepatocellular carcinoma showed unequivocal sinusoidal or peripheral reactivity for CD34. Five of seven cases of hepatocellular adenoma and four of nine cases of focal nodular hyperplasia showed > 50% sinusoidal reactivity for CD34. All 14 cases of cirrhosis showed peripheral to no sinusoidal reactivity. CONCLUSION: CD34 reactivity in a diffuse sinusoidal pattern can be helpful in the diagnosis of hepatocellular carcinoma. However, consideration should be given to the possibility of hepatocellular adenoma and focal nodular hyperplasia, which can also exhibit significant diffuse CD34 reactivity. In these cases, a reticulin stain may be helpful with the differential diagnosis.


Assuntos
Adenoma de Células Hepáticas/metabolismo , Antígenos CD34/metabolismo , Hiperplasia Nodular Focal do Fígado/metabolismo , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/metabolismo , Adenoma de Células Hepáticas/patologia , Biópsia por Agulha , Diagnóstico Diferencial , Hiperplasia Nodular Focal do Fígado/patologia , Humanos , Técnicas Imunoenzimáticas , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia
9.
Br J Anaesth ; 81(4): 610-1, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9924243

RESUMO

We have evaluated the intubating laryngeal mask airway (ILMA) for ventilation and for blind tracheal intubation. After induction of anaesthesia with fentanyl 1 microgram kg-1 and propofol 3 ml kg-1, the ILMA was placed successfully on the first attempt in all 100 patients. After administration of atracurium 0.5 mg kg-1, blind tracheal intubation was successful in 97% of patients--50% on the first attempt, 42% on the second and 5% on the third. Success was improved by pulling the metal handle of the ILMA towards the intubator in an "extension" manoeuvre, if intubation was not possible on the first attempt. These findings confirm the effectiveness of the ILMA in an Asian population.


Assuntos
Povo Asiático , Máscaras Laríngeas , Estudos de Avaliação como Assunto , Feminino , Humanos , Intubação Intratraqueal/instrumentação , Intubação Intratraqueal/métodos , Masculino , Singapura/etnologia , Resultado do Tratamento
10.
J Sports Sci ; 14(5): 425-32, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8941912

RESUMO

We have previously shown that regional chest wall impedance increases when the chest wall muscles are tonically contracted to perform isometric, non-respiratory tasks. To test how this affects breathing, we measured respiratory frequency, tidal volume, end-tidal PCO2, electromyographic activity (EMG) at four points on the chest wall surface, and regional displacements across six planes of the chest wall during maintenance of three different postures that necessitated strong tonic respiratory muscle contraction. These postures included a static push-up, a bilateral leg-lift and a partial sit-up. The subjects (n = 8) were able to maintain the postures for 1.5-2.5 min, and strong tonic EMG activity was observed in each posture at all points measured. The rate and depth of breathing and pattern of regional chest wall displacements were variable within the group of subjects and among the three postures. However, minute ventilation increased and end-tidal PCO2 decreased in each subject during each posture (P < 0.05). In six of the eight subjects, transdiaphragmatic pressure (Pdi) was measured during 1 min of the same exercises. The ratio of the breathing fluctuation in Pdi to tidal volume was at least twice as high compared with rest, except for two subjects during the leg-lifts. We conclude that strong tonic contraction of the chest wall muscles impedes, but does not limit, breathing, and that there is no single breathing strategy used during such conditions.


Assuntos
Exercício Físico/fisiologia , Fadiga Muscular , Respiração , Músculos Respiratórios/fisiologia , Adulto , Análise de Variância , Eletromiografia , Feminino , Humanos , Masculino , Contração Muscular , Fadiga Muscular/fisiologia , Mecânica Respiratória
11.
Am J Respir Crit Care Med ; 152(4 Pt 1): 1241-7, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7551377

RESUMO

We measured cardiorespiratory variables and 133xenon washout from a nonperfused lung region (XeW) in six anesthetized/paralyzed dogs, mechanically ventilated with 60% O2 at different positive end-expiratory pressures (PEEP). XeW in this technique represents directly measured acinar gas transfer (3). Measurements were repeated after induction of lung injury by lavaging the lungs 11 to 13 times with 600 ml saline. In control dogs, lung compliance (CL), alveolar ventilation (Valv), and XeW all decreased with increasing PEEP from 0 to 25 cm H2O (p < 0.05), while lung resistance (RL) did not change. After lavage, CL, Valv, and XeW below 15 cm H2O PEEP were all less than control values (p < 0.05), while RL was higher than control values. As PEEP increased from 0 to 20 cm H2O, Valv and XeW increased, but CL did not change; RL decreased only from 0 to 5 cm H2O. At 20 cm H2O PEEP, Valv and CL were not different from control values (p > 0.05), and XeW was higher than control values (p < 0.05). At estimated alveolar volumes above 400 ml, values for XeW before and after lavage were similar. We conclude that, during severe lung injury: (1) increasing PEEP to moderate levels will increase acinar gas transfer but, after a certain lung volume is reached, further increases in PEEP will have effects similar to the healthy condition; (2) overall mechanical properties of the lung do not reflect the responses to PEEP of the lung periphery.


Assuntos
Respiração com Pressão Positiva , Alvéolos Pulmonares/fisiologia , Troca Gasosa Pulmonar/fisiologia , Síndrome do Desconforto Respiratório/fisiopatologia , Animais , Débito Cardíaco/fisiologia , Cães , Complacência Pulmonar/fisiologia , Medidas de Volume Pulmonar , Alvéolos Pulmonares/fisiopatologia , Capacidade de Difusão Pulmonar/fisiologia , Síndrome do Desconforto Respiratório/terapia , Mecânica Respiratória/fisiologia , Radioisótopos de Xenônio
13.
Br J Anaesth ; 74(2): 201-8, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7696072

RESUMO

We compared in vitro oxyhaemoglobin saturations using two pulmonary artery catheters (catheter SO2), with oxyhaemoglobin saturations (SO2) measured by the IL282 co-oximeter and derived partial oxyhaemoglobin saturations (partial SO2) at different oxygen tensions (PO2) in six solutions: whole blood, 50:50 mixture of whole blood and Plasmalyte A (haemodiluted blood), 50:50 mixture of whole blood and 8% pyridoxylated haemoglobin-polyoxyethylene (PHP) conjugate (WB-PHP), 75:25 mixture of 8% PHP and Plasmalyte A solution (PHP66), 50:50 mixture of 8% PHP and Plasmalyte A solution (PHP44) and stroma-free haemoglobin solution (SFH). Calculated P50 values (PO2 vs SO2) were 3.79, 3.58, 3.49, 3.15, 3.04 and 2.07 kPa, respectively. However, if partial SO2 was used the curves were shifted to the left, reducing P50. Catheter SO2 correlated well with SO2 in whole blood (r2 > 0.99 for both catheters), haemodiluted blood (r2 > 0.98 for both catheters) and WB-PHP solution (r2 = 0.94 for both catheters). In PHP44 (r2 = 0.64 and r2 = 0.57), PHP66 (r2 = 0.40 for the Oximetrix and r2 = 0.25 for the Edwards catheter) and SFH solutions (r2 = 0.33 for the Oximetrix and r2 = 0.22 for the Edwards catheter) both catheters performed poorly. We conclude that mixed venous oxyhaemoglobin saturations measured by oximetric pulmonary artery catheters are inaccurate in the presence of haemoglobin solutions. For accuracy a multi-wavelength co-oximeter should be used if blood containing PHP or SFH is to be analysed.


Assuntos
Oxiemoglobinas/análise , Cateterismo Periférico/instrumentação , Hemoglobinas/análise , Humanos , Técnicas In Vitro , Oximetria/instrumentação , Polietilenoglicóis/análise , Artéria Pulmonar
14.
J Appl Physiol (1985) ; 76(2): 560-4, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8175563

RESUMO

We directly measured the effect of progressive pulmonary edema on gas transfer from the acinus by injecting 133Xe dissolved in saline through a pulmonary artery catheter into an acinar region with occluded blood flow and measuring 133Xe washout by gamma scintillation scanning. We measured washout in six anesthetized paralyzed dogs during mechanical ventilation with O2 before and after injection of 0.6 mg/kg of oleic acid into the right atrium, which induces severe pulmonary edema within 2 h. Changes in the elastance and resistance of the lung were also calculated from measurements of airway flow, airway pressure, and esophageal pressure. Before injection of oleic acid, the monoexponential rate constant for 133Xe washout was 3.6 +/- 1.4 (SE) min-1; from this we estimated that the rate of gas transfer of 133Xe from the acini was 1.0 l/min. The rate constant decreased gradually after the injection and was correlated with increases in elastance and resistance (r = -0.66) and decreases in alveolar PO2 (r = 0.71). At 2 h after injection, the rate constant (1.2 +/- 0.8 min-1) was lower than control (P < 0.01), and the rate of gas transfer of 133Xe from the acini was < 0.32 l/min. We conclude that resistance in the acini is increased during pulmonary edema and that it is correlated, in the oleic acid model, with changes in overall lung mechanical properties.


Assuntos
Edema Pulmonar/fisiopatologia , Ventilação Pulmonar , Sistema Respiratório/fisiopatologia , Animais , Cães , Coração/fisiopatologia , Complacência Pulmonar , Ácido Oleico , Ácidos Oleicos , Edema Pulmonar/induzido quimicamente , Respiração , Respiração Artificial , Xenônio
15.
Transplantation ; 46(2): 210-5, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2970132

RESUMO

The effects of T helper lymphocyte and Ia+ cell depletion were examined for their ability to independently and synergistically achieve prolongation of xenogeneic (rat-to-mouse) islet transplants. Recipient mice were depleted of T helper lymphocytes by short-term treatment with the anti-L3T4 monoclonal antibody GK1.5. Donor rat islets were treated prior to transplantation with a concentration of anti-Ia immunotoxin (13.4 x RT) that selectively depleted Ia+ cells within the islets while leaving functional insulin-secreting beta-cells unaffected. Anti-L3T4 treatment alone allowed transplants to be prolonged compared with untreated controls; however, all such treated mice rejected their xenogeneic transplant within 22 days. Although 13.4 x RT treatment of donor islets alone did not prolong engraftment, when donor rat islets were pretreated with the anti-Ia immunotoxin and grafted into L3T4-depleted mice, normoglycemia was maintained for greater than 50 days in 56% of transplants. These results suggest that neither L3T4 depletion nor anti-Ia immunotoxin treatment alone is enough to achieve indefinite survival of xenogeneic islets. However, decreasing the immunogenicity of the transplanted islets by anti-Ia immunotoxin treatment prior to transplantation into anti-L3T4 treated mice can allow greatly prolonged xenogeneic graft survival.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Ilhotas Pancreáticas/imunologia , Animais , Diabetes Mellitus Experimental/terapia , Imunotoxinas , Ilhotas Pancreáticas/citologia , Teste de Cultura Mista de Linfócitos , Camundongos , Ratos , Transplante Heterólogo
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