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1.
Scand J Urol ; 59: 131-136, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896113

RESUMO

OBJECTIVE: Disease recurrence, particularly intravesical recurrence (IVR) after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC), is common. We investigated whether violations of onco-surgical principles before or during RNU, collectively referred to as surgical violation (SV), were associated with survival outcomes.  Material and methods: Data from a consecutive series of patients who underwent RNU for UTUC 2001-2012 at Skåne University Hospital Lund/Malmö were collected. Preoperative insertion of a nephrostomy tube, opening the urinary tract during surgery or refraining from excising the distal ureter were considered as SVs. Survival outcomes in patients with and without SV (IVR-free [IVRFS], disease-specific [DSS] and overall survival [OS]) were assessed using multivariate Cox regression analyses (adjusted for tumour stage group, prior or concomitant bladder cancer, comorbidity and preoperative urinary cytology). RESULTS: Of 150 patients, 47 (31%) were subjected to at least one SV. Overall, SV was not associated with IVRFS (HR 0.81, 95% CI 0.4-1.6) but with worse DSS (HR 1.9, 95% CI 1.03-3.7) and OS (HR 1.9, 95% CI 1.2-3) in multivariable analysis. Additional analyses with a broader definition of SV including also preoperative instrumentation of the upper urinary tract (ureteroscopy and/or double J stenting) showed similar outcomes for DSS (HR 2.1, 95% CI 1.1-4.3). CONCLUSION: Worse survival outcomes, despite no difference in IVR, for patients that were subjected to the violation of sound onco-surgical principles before or during RNU for UTUC strengthen the notion that adhering to such principles is a cornerstone in upper tract urothelial cancer surgery.


Assuntos
Carcinoma de Células de Transição , Neoplasias Renais , Nefroureterectomia , Neoplasias Ureterais , Humanos , Nefroureterectomia/métodos , Feminino , Masculino , Idoso , Neoplasias Ureterais/cirurgia , Neoplasias Ureterais/mortalidade , Neoplasias Ureterais/patologia , Carcinoma de Células de Transição/cirurgia , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/patologia , Neoplasias Renais/cirurgia , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Pessoa de Meia-Idade , Taxa de Sobrevida , Estudos Retrospectivos , Recidiva Local de Neoplasia/epidemiologia , Idoso de 80 Anos ou mais , Ureter/cirurgia
2.
Eur Urol Open Sci ; 57: 37-44, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38020529

RESUMO

Background: There is limited information on the distribution of retroperitoneal lymph node metastases (LNMs) in upper tract urothelial carcinoma (UTUC). Objective: To investigate the location of LNMs in UTUC of the renal pelvis or proximal ureter and short-term complications after radical nephroureterectomy (RNU) with lymph node dissection (LND). Design setting and participants: This was a prospective Nordic multicenter study (four university hospitals, two county hospitals). Patients with clinically suspected locally advanced UTUC (stage >T1) and/or clinical lymph node-positive (cN+) disease were invited to participate. Participants underwent RNU and fractionated retroperitoneal LND using predefined side-specific templates. Outcome measurements and statistical analysis: The location of LNMs in the LND specimen and retroperitoneal lymph node recurrences during follow-up was recorded. Postoperative complications within 90 d of surgery were ascertained from patient charts. Descriptive statistics were used. Results and limitations: LNMs were present in the LND specimen in 23/100 patients, and nine of 100 patients experienced a retroperitoneal recurrence. Distribution per side revealed LNMs in the LND specimen in 11/38 (29%) patients with right-sided tumors, for whom the anatomically larger, right-sided template was used, in comparison to 12/62 (19%) patients with left-sided tumors, for whom a more limited template was used. High-grade complications (Clavien grade ≥3) within 90 d of surgery were registered for 13/100 patients. The study is limited in size and not powered to assess survival estimates. Conclusions: The suggested templates that we prospectively applied for right-sided and left-sided LND in patients with advanced UTUC included the majority of LNMs. High-grade complications directly related to the LND part of the surgery were limited. Patient summary: This study describes the location of lymph node metastases in patients with cancer in the upper urinary tract who underwent surgery to remove the affected kidney and ureter. The results show that most metastases occur within the template maps for lymph node surgery that we investigated, and that this surgery can be performed with few severe complications.

3.
Scand J Urol ; 58: 4-10, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37096322

RESUMO

OBJECTIVE: To report population-based clinical presentation and outcomes in patients with urosymphyseal fistula (USF) after pelvic radiotherapy (RT). PATIENTS AND METHODS: A retrospective chart review was performed in 33 consecutive patients diagnosed with suspicion of USF in a tertial referral center from 2014-2022 to ascertain information about diagnostic delay, clinical presentation, precipitating causes, treatments received and outcomes during the median 22 months follow-up. Out of 33 consecutive patients with suspicion of USF, one female with vesicovaginal fistula, one patient developing RT-associated bladder angiosarcoma, four patients with short follow-up (<3 months), and three patients that during chart review not were considered to have a USF were excluded. RESULTS: In all, 24 males with a median age of 77 years were diagnosed with USF. Local pain was the predominating symptom in 17/24 (71%) patients. Endourologic manipulations preceded the diagnosis of USF in 16 patients. Five patients had a diagnostic delay of more than 3 months. At diagnosis, 20/24 patients had radiological signs of osteomyelitis, and five had a concomitant rectourethral fistula. Due to comorbidity, five patients were not amenable to any other interventions than urinary catheter or suprapubic tube in conjunction with long-term antibiotics, of which three died from infections related to the USF. Out of the remaining 19 patients receiving some form of urinary diversion, five had recurrent osteomyelitis, of which four did not undergo cystectomy in conjunction with surgery for the USF. CONCLUSIONS: Urethral endourologic interventions in patients previously subjected to pelvic RT should be performed cautiously.


Assuntos
Osteomielite , Derivação Urinária , Fístula Urinária , Masculino , Humanos , Feminino , Idoso , Estudos Retrospectivos , Diagnóstico Tardio/efeitos adversos , Fístula Urinária/etiologia , Derivação Urinária/efeitos adversos , Comorbidade , Osteomielite/complicações , Osteomielite/cirurgia
4.
Scand J Urol ; 56(2): 155-161, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35019814

RESUMO

Objective: To prospectively assess anorectal dysfunction using patient-reported outcomes using validated questionnaires, manovolumetry and endoanal ultrasound before and 12 months after RC.Patients and methods: From 2014 to 2019, we prospectively included 44 patients scheduled for RC. Preoperatively and 12 months after surgery, 41 patients filled in a low anterior resection syndrome score (LARS-score) to assess fecal incontinence, increased frequency, urgency and emptying difficulties and a St Mark's score to assess fecal incontinence in conjunction with manovolumetry and endoanal ultrasound examinations. Pre- and postoperative patient-reported anorectal dysfunction were assessed by LARS-score and St Marks's score. At the same time-points, anorectal function was evaluated by measuring mean anal resting and maximal squeeze pressures, volumes and pressures at first desire, urgency to defecate and maximum toleration during manovolumetry. Wilcoxon's signed rank test was used to compare pre- and postoperative outcomes by questionnaires.Results: Postoperatively 6/41 (15%) patients reported flatus incontinence assessed by the LARS-questionnaire, and correspondingly the St Mark's score increased postoperatively. The median anal resting pressure decreased from 57 mmHg preoperatively to 46 mmHg after RC, but without any postoperative anatomic defects detected by endoanal ultrasound. Volumes and pressures at first desire, urgency to defecate and maximum toleration during manovolumetry all increased after RC, indicating decreased postoperative rectal sensation, as rectal compliance was unaltered.Conclusions: Postoperative flatus incontinence is reported by one out of seven patients after RC, which corresponds to decreased anal resting pressures. The finding of decreased rectal sensation might also contribute to patient-reported symptoms and anorectal dysfunction after RC.


Assuntos
Incontinência Fecal , Neoplasias Retais , Neoplasias da Bexiga Urinária , Cistectomia/efeitos adversos , Incontinência Fecal/etiologia , Incontinência Fecal/cirurgia , Feminino , Flatulência/cirurgia , Humanos , Masculino , Manometria , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Neoplasias Retais/cirurgia , Reto , Síndrome , Neoplasias da Bexiga Urinária/cirurgia
5.
BJU Int ; 129(2): 174-181, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33626220

RESUMO

OBJECTIVE: To determine whether repeated [18 F]fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET-CT) scans can predict increased cancer-specific survival (CSS) after induction chemotherapy followed by radical cystectomy (RC). PATIENTS AND METHODS: Between 2007 and 2018, 86 patients with clinically lymph node (LN)-positive bladder cancer (T1-T4, N1-N3, M0-M1a) were included and underwent a repeated FDG-PET-CT during cisplatin-based induction chemotherapy. The 71 patients that had a response to chemotherapy underwent RC. Response to chemotherapy was evaluated in LNs through repeated FDG-PET-CT and stratified as partial response or complete response using three different methods: maximum standardised uptake value (SUVmax ), adapted Deauville criteria, and total lesion glycolysis (TLG). Progression-free survival (PFS) and CSS were analysed for all three methods by Cox regression analysis. RESULTS: After a median follow-up of 40 months, 15 of the 71 patients who underwent RC had died from bladder cancer. Using SUVmax and the adapted Deauville criteria, multivariable Cox regression analyses adjusting for age, clinical tumour stage and LN stage showed that complete response was associated with increased PFS (hazard ratio [HR] 3.42, 95% confidence interval [CI] 1.20-9.77) and CSS (HR 3.30, 95% CI 1.02-10.65). Using TLG, a complete response was also associated with increased PFS (HR 5.17, 95% CI 1.90-14.04) and CSS (HR 6.32, 95% CI 2.06-19.41). CONCLUSIONS: Complete metabolic response with FDG-PET-CT predicts survival after induction chemotherapy followed by RC in patients with LN-positive bladder cancer and comprises a novel tool in evaluating response to chemotherapy before surgery. This strategy has the potential to tailor treatment in individual patients by identifying significant response to chemotherapy, which motivates the administration of a full course of induction chemotherapy with a higher threshold for suspending treatment due to toxicity and side-effects.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Bexiga Urinária , Cistectomia , Fluordesoxiglucose F18/farmacologia , Humanos , Quimioterapia de Indução , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Metástase Linfática/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Prognóstico , Compostos Radiofarmacêuticos/uso terapêutico , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/cirurgia
9.
Eur Urol ; 78(5): 757-763, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32800407

RESUMO

BACKGROUND: Parastomal hernia (PSH) after urinary diversion with ileal conduit is frequently a clinical problem. OBJECTIVE: To investigate whether a prophylactic lightweight mesh in the sublay position can reduce the cumulative incidence of PSH after open cystectomy with ileal conduit. DESIGN, SETTING, AND PARTICIPANTS: From 2012 to 2017, we randomised 242 patients 1:1 to conventional stoma construction (n = 124) or prophylactic mesh (n = 118) at three Swedish hospitals (ISRCTN 95093825). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was clinical PSH, and secondary endpoints were radiological PSH assessed in prone position with the stoma in the centre of a ring, parastomal bulging, and complications from the mesh. RESULTS AND LIMITATIONS: Within 24 mo, 20/89 (23%) patients in the control arm and 10/92 (11%) in the intervention arm had developed a clinical PSH (p = 0.06) after a median follow-up of 3 yr, corresponding to a hazard ratio of 0.45 (confidence interval 0.24-0.86, p = 0.02) in the intervention arm. The proportions of radiological PSHs within 24 mo were 22/89 (25%) and 17/92 (19%) in the two study arms. During follow-up, five patients in the control arm and two in the intervention arm were operated for PSH. The median operating time was 50 min longer in patients receiving a mesh. No differences were noted in proportions of Clavien-Dindo complications at 90 d postoperatively or in complications related to the mesh during follow-up. CONCLUSIONS: Prophylactic implantation of a lightweight mesh in the sublay position decreases the risk of PSH when constructing an ileal conduit without increasing the risk of complications related to the mesh. The median surgical time is prolonged by mesh implantation. PATIENT SUMMARY: In this randomised report, we looked at the risk of parastomal hernia after cystectomy and urinary diversion with ileal conduit with or without the use of a prophylactic mesh. We conclude that such a prophylactic measure decreased the occurrence of parastomal hernias, with only a slight increase in operating time and no added risk of complications related to the mesh.


Assuntos
Cistectomia , Hérnia Incisional/prevenção & controle , Telas Cirúrgicas , Estomas Cirúrgicos , Neoplasias da Bexiga Urinária/cirurgia , Derivação Urinária , Idoso , Cistectomia/métodos , Feminino , Humanos , Masculino , Estudos Prospectivos
11.
Scand J Urol ; 53(5): 339-343, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31385741

RESUMO

Objective: In Sweden complications after radical cystectomy have been reported to the nationwide population-based Swedish Cystectomy Registry since 2011. Here, validation of the reporting was assessed in two healthcare regions.Materials and methods: Complications were ascertained from patient records by a third party not involved in the care delivered to 429 randomly selected patients from 949 who had undergone radical cystectomy since 2011 in four hospitals. Without knowledge of the outcome in the primary registration, post-operative complications within 90 days post-operatively were assessed by an independent review of patient charts, and the results were compared with the primary reports in the Swedish Cystectomy Registry.Results: The third-party assessment identified post-operative complications in 310 patients (72%). Low-grade complications (Clavien-Dindo I-II) were noted in 110 (26%) of the patients in the primary registration, but increased to 182 (42%) in the validation (p < 0.00001). High-grade complications (Clavien-Dindo III-V) were reported in 113 (26%) patients in the primary registration, but in 128 (30%) of the patients in the validation (p = 0.02). According to the third-party assessment, 18 patients (4%) had Clavien-Dindo grade IV complications and 12 (3%) died within 90 days of surgery (Clavien-Dindo grade V); corresponding values in the primary registration were 15 (3%) and 9 (2%), respectively. The readmission rate within 90 days increased from 27 to 32% in the validation (p < 0.00001).Conclusions: Compared with registry data, third-party assessment revealed more complications and readmissions after radical cystectomy. Hence such evaluation may improve the validity of reported complication data.


Assuntos
Cistectomia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Sistema de Registros , Gestão de Riscos/estatística & dados numéricos , Idoso , Cistectomia/métodos , Feminino , Humanos , Masculino , Estudos Retrospectivos , Suécia
13.
Scand J Urol ; 53(2-3): 109-115, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31064253

RESUMO

Objective: In non-muscle-invasive bladder cancer (NMIBC), local recurrence after transurethral resection of the bladder (TURB) is common. Outcomes vary between urological centres, partly due to the sub-optimal surgical technique and insufficient application of measures recommended in the guidelines. This study evaluated early recurrence rates after primary TURB for NMIBC before and after introducing a standardized treatment protocol. Methods: Medical records of all patients undergoing primary TURB for NMIBC in 2010 at Skåne University Hospital, Malmö, Sweden, were reviewed. A new treatment protocol for NMIBC was defined and introduced in 2013, and results documented during the first year thereafter were compared with those recorded in 2010 prior to the intervention. The primary endpoint was early recurrence at first control cystoscopy. Comparisons were made by Chi-square analysis and Fisher's exact test. Recurrence-free survival (RFS) in the two cohorts was also investigated. Results: TURB was performed on 116 and 159 patients before and after the intervention, respectively. The early recurrence rate decreased from 22% to 9.6% (p = 0.005) at the first control cystoscopy after treatment. Residual/Recurrent tumour at the first control cystoscopy after the primary TURB (i.e. at second-look resection or first control cystoscopy) decreased from 31% to 20% (p = 0.038). The proportion of specimens containing muscle in T1 tumours increased from 55% to 94% (p < 0.001). RFS was improved in the intervention group (HR = 0.65, CI = 0.43-1.0; p = 0.05). Conclusions: Introduction of a standardized protocol and reducing the number of surgeons for primary treatment of NMIBC decreased the early recurrence rate from 22% to 9.6% and lowered the recurrence incidence by 35%.


Assuntos
Carcinoma de Células de Transição/cirurgia , Cistoscopia/normas , Recidiva Local de Neoplasia/prevenção & controle , Guias de Prática Clínica como Assunto , Neoplasias da Bexiga Urinária/cirurgia , Administração Intravesical , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Carcinoma de Células de Transição/patologia , Quimioterapia Adjuvante , Feminino , Humanos , Masculino , Músculo Liso/patologia , Invasividade Neoplásica , Recidiva Local de Neoplasia/epidemiologia , Indicadores de Qualidade em Assistência à Saúde , Qualidade da Assistência à Saúde , Estudos Retrospectivos , Suécia/epidemiologia , Neoplasias da Bexiga Urinária/patologia
16.
Eur Urol ; 71(6): 851-853, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27771127

RESUMO

Radical cystectomy with neoadjuvant chemotherapy is the gold standard for treating muscle-invasive bladder cancer. Women subjected to radical cystectomy are frequently postmenopausal, and the median age for bladder cancer diagnosis in women in Sweden is currently 73 yr (Swedish National Bladder Cancer Register). Traditionally, most women treated with radical cystectomy have undergone simultaneous bilateral oophorectomy and hysterosalpingectomy to diminish the risk of later ovarian disease and ovarian bladder cancer recurrence, but also the belief that there is no impact on health or health-related quality of life associated with oophorectomy and the fact that it might be easier surgery to take the ovarian pedicles, rather than sparing the ovaries. However, pelvic organ preservation is considered in some younger women to diminish postoperative functional impairment. Based on recent literature in several areas related to oophorectomy, we question the rationale and arguments for performing oophorectomy in women in conjunction with radical cystectomy for bladder cancer.


Assuntos
Cistectomia , Neoplasias Ovarianas/cirurgia , Ovariectomia , Procedimentos Desnecessários , Neoplasias da Bexiga Urinária/cirurgia , Adulto , Fatores Etários , Idoso , Tomada de Decisão Clínica , Cistectomia/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/secundário , Ovariectomia/efeitos adversos , Seleção de Pacientes , Medição de Risco , Fatores de Risco , Fatores Sexuais , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologia
17.
Cell Transplant ; 21(6): 1269-83, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22405036

RESUMO

In this study, we evaluated the effects of exendin-4 on free and encapsulated islet grafts in a rodent model. We also investigated the role of a transcription factor, hypoxia-inducible factor-1 (HIF-1), in mediating the beneficial effects of exendin-4. Diabetic athymic mice were transplanted with free rat islets under the kidney capsule or with macroencapsulated rat islets SC with or without exendin-4, islet preculture (exendin-4 0.1 nM for 20 h), and/or recipient treatment (IP 100 ng/day, day 0-7). The mice were followed for 4 weeks and the graft function and ß-cell volume were evaluated. The effects of exendin-4 on islet HIF-1α mRNA and protein expression and on ATP content in a rat insulinoma cell line (INS-1E) were also examined. Preculture with exendin-4 followed by recipient treatment improved the outcome of both free (73% graft function vs. 26% in controls, p = 0.03) and macroencapsulated islet grafts (100% vs. 25% in controls, p = 0.02). In macroencapsulated grafts, the exendin-4-treated group had significantly larger endocrine volume, less graft necrosis, and more blood vessels around the capsule. In rat islets cultured with exendin-4, HIF-1α mRNA and protein expression were significantly enhanced. ATP content was increased in exendin-4-treated INS-1E cells under hypoxic conditions. The improved functional outcome after transplantation of a marginal islet mass with a brief initial treatment with exendin-4 is related to a larger surviving endocrine cell volume. Exendin-4 may improve islet graft resistance to hypoxia during the peritransplant period by increasing the expression of HIF-1α.


Assuntos
Sistema Endócrino/anatomia & histologia , Hipoglicemiantes/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Peptídeos/farmacologia , Peçonhas/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Caspase 3/metabolismo , Hipóxia Celular , Linhagem Celular Tumoral , Tamanho Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/terapia , Exenatida , Proteínas de Homeodomínio/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Insulina/metabolismo , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/metabolismo , Transplante das Ilhotas Pancreáticas , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Transativadores/metabolismo
18.
Transplantation ; 86(2): 364-6, 2008 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-18645504

RESUMO

Islet graft survival inside macroencapsulation devices is suboptimal. We hypothesized that induction of neovascularization by preimplantation of devices would improve the physiological conditions, thereby lowering the number of islets required for cure. Several rat islets were transplanted to TheraCyte immunoprotective devices implanted subcutaneously in diabetic athymic mice. Cure rates in the groups with preimplanted devices were significantly better than in those with freshly implanted devices (375 islets: 8/8 vs. 1/6, P=0.003; 125 islets: 6/6 vs. 0/7, P=0.001). Morphometric evaluations of the 125 islet groups showed higher fractional and absolute volumes of endocrine tissue in the group with preimplanted devices (P<0.001 and P=0.035, respectively). In the following dose titration study, using preimplanted devices, as low as 50 islets cured diabetic mice (100% cure, n=6). We conclude that preimplantation significantly lowers the curative dose of macroencapsulated islets to levels resembling those of free islets transplanted under the renal capsule.


Assuntos
Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/citologia , Animais , Diabetes Mellitus Experimental/terapia , Sistema Endócrino , Desenho de Equipamento , Feminino , Glucose/metabolismo , Teste de Tolerância a Glucose , Sobrevivência de Enxerto , Camundongos , Camundongos Nus , Implantação de Prótese , Fatores de Tempo , Resultado do Tratamento
19.
Transplantation ; 82(3): 393-7, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16906039

RESUMO

BACKGROUND: The aim of this study was to evaluate the risks of sensitization by islet grafts encapsulated in a bilaminar immunoprotective membrane. METHODS: We studied five groups of Lewis rats: one control group (no islets), two groups that received free islets (200 or 1000 s.c.), and two groups that received encapsulated ones (200 or 1000 s.c.) from Dark Agouti (DA) rats. Four weeks later, abdominal heterotopic DA-heart transplantation was performed on the same recipients. The time-to-heart graft rejection was assessed by the cessation of heart contractions. Rejection was confirmed by histological examinations. Antidonor antibodies were determined by fluorescence activated cell sorter (FACS) analysis. RESULTS: The control animals had a mean heart graft survival of 6.4 days. The free islet groups had significantly shorter heart graft survivals-i.e., 4.8 days (200 islets) and 1.0 day (1000 islets) (P < 0.001)-while those of the encapsulated islet groups were about the same as that of the control group-i.e., 6.4 days (200 islets) and 6.0 days (1000 islets). In the free islet groups, anti-DA antibodies developed in 7/10 (200 islets) and 8/8 (1000 islets) animals after the islet transplantation. In the encapsulated groups, 1/10 (200 islets) and 3/8 (1000 islets) animals developed anti-DA antibodies after these transplantations. All animals had anti-DA antibodies at the time of heart graft rejection. On histological examination all grafts showed various features of rejection. CONCLUSIONS: The bilaminar membrane protects against sensitization and prevents accelerated rejection of a subsequent vascularized graft, at least during the first month after the islet transplantation.


Assuntos
Transplante das Ilhotas Pancreáticas/imunologia , Politetrafluoretileno , Animais , Anticorpos/imunologia , Formação de Anticorpos/imunologia , Sobrevivência de Enxerto/imunologia , Transplante de Coração/imunologia , Transplante das Ilhotas Pancreáticas/patologia , Ratos , Doadores de Tecidos , Transplante Homólogo/imunologia
20.
Cell Transplant ; 13(6): 713-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15648741

RESUMO

The aim of this study was to determine which vessels are important for the exchange of small molecules, such as glucose, from the microcirculation into an immunoisolation device. Reasonably, those vessels should be the ones of interest in histological evaluations. In a previous study, we examined the diffusion of glucose from the microcirculation into immunoisolation devices that had been implanted subcutaneously in rats for various times (i.e., 1, 2, and 4 weeks and 3 months). The glucose kinetic data were then correlated with the number of vascular profiles within 15 and 250 microm from the device. Significant correlations were found only at 250 microm. To examine the relation further between function and vascularization, we used the histological samples from the previous study and counted vascular profiles within various distances between 15 and 400 microm from the device. The number was then correlated with the already available glucose kinetic data. The highest correlations were found at 75 and 100 microm (p < 0.05). We therefore suggest that vascular profiles within 100 microm should be used when evaluating the vascularity of tissue surrounding an immunoisolation device. We also studied neovascularization asymmetries between the side of the membrane facing the skin and that facing the muscle. At 1 and 2 weeks about half of the devices were mainly vascularized on the side facing the skin, whereas the rest were equally vascularized on the two sides. At 3 months, all devices were well vascularized, and no striking vascularization asymmetries were seen.


Assuntos
Transplante de Células/instrumentação , Glucose/metabolismo , Implantes Experimentais , Neovascularização Fisiológica , Animais , Materiais Biocompatíveis , Técnicas Histológicas/métodos , Masculino , Microcirculação/fisiologia , Músculo Liso/irrigação sanguínea , Músculo Liso/metabolismo , Ratos , Ratos Sprague-Dawley , Pele/irrigação sanguínea , Pele/metabolismo
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