Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
1.
J Robot Surg ; 18(1): 168, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598047

RESUMO

The MMI Symani® is a recently approved robotic microsurgical system for surgical procedures in adults. The system enables the surgeon to create microanastomoses. Clinical applications so far include lymphatic vessels surgery and the creation of special flap plastics. The use of the system in coronary arteries has not yet been assessed. The aim of this preclinical study was to evaluate the applicability of the Symani® surgical system in the creation of coronary anastomoses a cadaveric porcine model. A total of 12 anastomoses were performed by three senior cardiovascular surgeons on the left main coronary artery of three porcine hearts. Artificial bypasses (diameter 1 mm) were performed to the left main trunk. The anastomoses were performed with the Symani® surgical system. Evaluation included procedure times and anastomosis leakage. All anastomoses could be successfully performed. The procedure time decreased due to the learning curve between the first anastomosis 47:28 ± 5:30 min and the last anastomosis 22:37 ± 3:25 min. The final evaluation of the anastomoses showed excellent results with low leakage. The quality of the anastomosis also improved in relation to the increasing learning curve. The Symani® surgical system could be used to create coronary anastomoses in an acceptable time frame and without technical failures. Hence, the system appears feasible for conventional coronary surgery. Further studies in animal models are mandatory prior to clinical application.


Assuntos
Procedimentos Cirúrgicos Robóticos , Cirurgiões , Adulto , Suínos , Humanos , Animais , Procedimentos Cirúrgicos Robóticos/métodos , Ponte de Artéria Coronária , Anastomose Cirúrgica , Cadáver
2.
CVIR Endovasc ; 6(1): 57, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38019379

RESUMO

A 66-year-old female presented in the emergency department with Blue-Toe-Syndrome (BTS) and signs of osteitis of her left big toe. Imaging workup of the peripheral vasculature showed no findings. Upon invasive angiography, severe focal stenosis of the dorsalis pedis artery (DPA) could be seen at the talonavicular joint. Complete regression of the stenosis was inducible by dorsal extension in the ankle joint. Further imaging revealed an underlying subluxation of the talonavicular joint as cause of the arterial compression. Entrapment of the DPA is a rare condition and most often described in relation to connective tissue bands or variant muscular tendons (McCabe et al. 70:213-8, 2021; Weichman et al. 24:113, 2010; Smith et al.58:212-4, 2013; Griffin et al. 20:325-8; 2012). In the presented case, bony compression of the PDA due to cranial subluxation of the talus was seen as the cause of BTS and osteitis of the phalanx of the first toe.

3.
J Endovasc Ther ; 30(4): 600-608, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35466775

RESUMO

OBJECTIVES: This study's objective was to evaluate Endurant II (Medtronic Inc, Minneapolis, Minnesota) stent graft's early and midterm outcomes and compare the results according to the anatomic severity grade (ASG) scores. METHODS: This was a retrospective study of patients treated with the Endurant II stent graft between January 2013 and May 2021. The patients were divided into 2 independent groups, including those with a low ASG score (score <14) and a high ASG score (score >14). RESULTS: A total of 165 consecutive patients (89% males, age 74±8 years) were included. There were 110 (67%) patients in the low-score group and 55 (33%) patients in the high-score group. Technical success was achieved in all cases. Primary clinical success at 30 days was 100% and at 1 year was 96%. Median operative time was longer in the high-score group with no statistical significance (133 vs 120 minutes, p=0.116). The median dose area product of low-score patients (50.9 Gy·cm2; IQR 22.4-75.5 Gy·cm2) was significantly lower than high-score patients (85.0 Gy·cm2; IQR 46.5-127.9 Gy·cm2) with p=0.025. Median fluoroscopic time was lower in low-score patients (17 minutes; IQR 13-24 minutes) compared with high-score patients (19 minutes; IQR 16-23 minutes) without a significant difference at p=0.148. At a midterm follow-up of 32 months (range 2-63 months), combined complications (29% vs 8%, p<0.001) and implant-related complications (13% vs 4%, p=0.043) were higher in the high-score group. Systemic complications at 30 days were higher in the high-score group without a statistically significant difference (15% vs 11%, p=0.500). The Kaplan-Meier estimate of freedom from reintervention was significantly higher in the low-risk group at 1 (97% vs 90%), 2 (96% vs 88%), and 3 years (96% vs 85%) with (p=0.035). The cumulative survival rate was significantly higher in the low-score group than high-score group (p=0.001) at 1 (99% vs 87%), 2 (98% vs 85%), and 3 years (96% vs 82%). CONCLUSIONS: Endurant II endovascular aneurysm repair seems to be safe in both low-score and high-score patients. However, patients in the high-score group showed more implant-related complications and midterm mortalities than those in the low-score group.


Assuntos
Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Procedimentos Endovasculares , Masculino , Humanos , Idoso , Idoso de 80 Anos ou mais , Feminino , Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Aneurisma da Aorta Abdominal/cirurgia , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Desenho de Prótese , Fatores de Tempo , Procedimentos Endovasculares/efeitos adversos , Stents/efeitos adversos , Complicações Pós-Operatórias/etiologia
4.
Vascular ; 31(5): 850-857, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35549485

RESUMO

OBJECTIVE: To report and compare neoaortoiliac system reconstruction and cryopreserved human allograft in treating aortic graft infections. METHODS: We retrospectively analysed the data of the patients treated for aorto graft infections between January 2015 and May 2021 in our hospital. The clinical data, diagnostic procedures, and surgical options were evaluated. The primary endpoint of this study was the 30-day and 1-year mortality; secondary endpoints were major postoperative complications. RESULTS: We retrospectively reviewed a series of 31 consecutive patients (28 males; median age 72 years, range, 50-87 years) with aortic graft infection treated with NAIS (n = 20, 65%) or cryopreserved allograft (n = 11, 36%). The clinical presentation included fever attacks in 18 (58%) patients, abdominal pain in 15 (48%) patients, haemodynamic instability in 6 (19%) patients, and haematemesis in 2 (7%) patients. The median operative time of the NAIS was longer than CHA without a statistically significant difference (458 min vs. 359 min, p = .505). The postoperative morbidity for all patients was 81%, with no significant difference between NAIS and CHA groups (85% vs. 73%, p = .638). There was no limb thrombosis of the new reconstructions. Limb loss occurred in 4 (13%) patients, including 2 (10%) NAIS patients and 2 (18%) CHA patients. One NAIS patient developed complications in the form of a distal (femoral) disruption of the vein 15 days after surgery. There were no significant differences between NAIS and CHA groups in ICU stay (12 vs 8 days, .984) but in hospitalization (22 vs 33, p = .033). The most common bacteria isolated were staphylococci strains in 15 (48%). In 13 (36%) patients, candida was positive. The in-hospital 30-day and 1-year mortality for all patients was 16% (5/31) and 29% (9/31), with no significant differences between NAIS and CHA at 30 days (25% vs. 0, p = .133) or 1 year (35% vs. 18%, .429). Five NAIS patients died during the hospital stay; three of them had end-of-life decisions. After a median follow-up of 16 months (1-66 months), 12 (39%) patients died, including 9 patients with NAIS and 3 with CHA reconstructions. The causes of death included overwhelming sepsis in 5 (42%) patients, graft disruption in one (8%) NAIS patient, non-small cell lung cancer in one (8%) patient, COVID-19 in one (8%) patient and unknown causes (8%) in one. CONCLUSIONS: Non-staged neoaortoiliac system reconstruction and cryopreserved human allografts show comparable short- and midterm results for treating aortic graft infections. However, both procedures remain challenging with high morbidity and mortality rates.


Assuntos
Implante de Prótese Vascular , COVID-19 , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Infecções Relacionadas à Prótese , Masculino , Humanos , Idoso , Prótese Vascular/efeitos adversos , Estudos Retrospectivos , Carcinoma Pulmonar de Células não Pequenas/etiologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/cirurgia , Infecções Relacionadas à Prótese/microbiologia , Resultado do Tratamento , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/cirurgia , Implante de Prótese Vascular/efeitos adversos , Aloenxertos/cirurgia , Fatores de Risco
5.
Ann Vasc Surg ; 85: 305-313, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35271960

RESUMO

BACKGROUND: A critical step in the endovascular treatment of complex aortic aneurysms is the cannulation and stenting of renovisceral vessels, especially in cases with a complex anatomy or atherosclerotic lesions. This study aimed to demonstrate the results of renovisceral vessel cannulation using a steerable sheath in fenestrated or branched endovascular aortic procedures (FB-EVAR). METHODS: Patients undergoing elective FB-EVAR for asymptomatic thoracoabdominal or juxtarenal aneurysm at a single tertiary referral center from 2016 to 2019 were included in this study. Underlying pathologies, renovisceral target vessels (TV), technical success (TS), freedom from reintervention (FFR), and TV patency were assessed. Target vessels were categorized as challenging or nonchallenging TV. RESULTS: Fifty-three patients (median age 73 (Q1, Q3 (68-80)); 43 male (81%)) who underwent elective FB-EVAR were included. Indications comprised thoracoabdominal aneurysms (Crawford I-IV) (n = 26; 49%), juxtarenal aneurysms (n = 23; 43.5%) and penetrating aortic ulcers (PAU) (n = 4; 7.5%). Two patients (4%) had prior open aortic surgery, and three patients (6%) had undergone a failed standard EVAR before. Of the 196 treated TV, 131 (67%) were categorized as challenging. Cannulation was successful in 194 of 196 vessels (99%). A total of 3 TV (1.5%) showed periprocedural complications. No significant difference was found in the rate of intraoperative complications between challenging versus nonchallenging TV (P = 0.457). One patient died within 30 days of the procedure (1.9%). No stroke or intestinal ischemia occurred. After 12, 24, and 36 months, the survival rate was 87%, 87%, and 81%, respectively. Primary patency after 12 months was 98.6%, and 97.9% of vessels remained FFR during follow-up. CONCLUSIONS: Transfemoral, retrograde cannulation of renovisceral vessels using a steerable sheath is feasible and safe and provides good mid-term results, especially in cases with challenging renovisceral vessels. The potential complications of antegrade vascular access can be avoided.


Assuntos
Aneurisma da Aorta Abdominal , Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Procedimentos Endovasculares , Idoso , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Cateterismo/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Humanos , Masculino , Complicações Pós-Operatórias/etiologia , Desenho de Prótese , Estudos Retrospectivos , Resultado do Tratamento
6.
Vasa ; 51(3): 150-157, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35311548

RESUMO

Background: This study aimed to evaluate risk factors for adverse outcomes and perioperative stroke and death in patients with symptomatic carotid stenosis undergoing open endarterectomy (CEA). The second objective was to assess the predictive value of the POSSUM and V-POSSUM models for predicting morbidity and mortality from CEA in symptomatic carotid stenosis. Patients and methods: A retrospective observational study of all patients admitted to a single center who underwent CEA for symptomatic carotid stenosis was performed. 320 patients from 1999 to 2013 were included. Postoperative complications, 30-day survival, and stroke rates were recorded. The observed outcomes were compared to the POSSUM and V-POSSUM expected mortality (observed to expected ratio (O:E)). Results: The mean age was 68.1±10.0 years. 215 patients were male (67%). Risk factors for surgical complications were: age, with a higher risk in both groups of less than 60 years and more than 75 years of age (p=0.04), a higher ASA score (p=0.04), and hyperlipidemia (p=0.017). Risk factors for the combined endpoint stroke or death were a higher ASA category (p<0.001), stroke as indication for CEA (p 0.022), and a high degree of stenosis (p=0.019). For POSSUM predicted mortality, there was a good O:E ratio in the two lowest risk groups, but a 2-fold overprediction of death or stroke in the two high-risk strata. The area under the curve (AUC) was 0.58 (95% CI: 0.43-0.73). The V-POSSUM showed a better fit in the high-risk groups, but an underprediction of mortality in the low-risk strata. Conclusions: Age and comorbid conditions are risk factors for adverse outcomes after CEA. The V-POSSUM model is better than POSSUM to predict postoperative death and stroke after CEA in patients with symptomatic carotid stenosis and a high preoperative physiological score. In patients with low physiological scores, both POSSUM and V-POSSUM show a limited predictive value.


Assuntos
Estenose das Carótidas , Endarterectomia das Carótidas , Acidente Vascular Cerebral , Idoso , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Stents , Acidente Vascular Cerebral/etiologia , Fatores de Tempo , Resultado do Tratamento
7.
J Vasc Surg ; 74(3): 711-719.e1, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33684467

RESUMO

OBJECTIVE: In the present study, we have reported and compared aortoduodenal fistulas (ADFs) after endovascular abdominal aortic aneurysm repair (EVAR) vs after open aortic repair (OAR). METHODS: We retrospectively analyzed the data from patients treated for ADFs from January 2015 to May 2020 in our hospital. The clinical data, diagnostic procedures, and surgical options were evaluated. The primary endpoints of the present study were 30-day and 1-year mortality. The secondary endpoints were major postoperative complications. RESULTS: A total of 24 patients (20 men; median age, 69 years; range, 53-82 years) were admitted with ADFs after EVAR (n = 9) or OAR (n = 15). These patients accounted for ∼4.3% of all abdominal aortic aneurysm repairs in our hospital. The median interval from the initial aortic repair and the diagnosis of ADF was 68 months (range, 6-83 months) for the ADF-EVAR group and 80 months (range, 1-479 months) for the ADF-OAR group. Three patients in the ADF-EVAR group had refused surgical treatment owing to their high surgical risk. One patient in the ADF-OAR group had undergone removal of the aortic prosthesis without replacement. Of the remaining 20 patients, 12 (ADF-EVAR group, n = 4; ADF-OAR group, n = 8) had undergone in situ replacement of the aorta and 8 (ADF-EVAR group, n = 2; ADF-OAR group, n = 6) had undergone extra-anatomic reconstruction with aortic ligation. After a mean follow-up of 26 months, no patient had experienced early limb loss. However, one case of rupture of the venous graft (ADF-EVAR), one case of aortic stump blowout (ADF-OAR), and one case of a ureteroarterial fistula with a homograft (ADF-OAR) had occurred. Overall, the incidence of postoperative complications was significantly greater after ADF-OAR (93% vs 33%; P = .036). The most frequent bacteria involved in the blood cultures were Escherichia coli (25% of patients), and Candida spp. (61%) were the predominant pathogens found on intra-abdominal smears. The in-hospital mortality rates for the ADF-EVAR and ADF-OAR group were 22% and 13%, respectively. The corresponding 1 -year mortality rates were 22% and 33%. CONCLUSIONS: Patients with ADFs after EVAR or OAR have limited overall survival. In addition to the similar therapeutic approaches, we found no significant differences in postoperative mortality between these two uncommon pathologic entities. In our study, the overall postoperative morbidity seemed greater for the ADF-OAR group.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Duodenopatias/etiologia , Procedimentos Endovasculares/efeitos adversos , Fístula Intestinal/etiologia , Fístula Vascular/etiologia , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/mortalidade , Implante de Prótese Vascular/mortalidade , Bases de Dados Factuais , Remoção de Dispositivo , Duodenopatias/diagnóstico por imagem , Duodenopatias/mortalidade , Duodenopatias/cirurgia , Procedimentos Endovasculares/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Fístula Intestinal/diagnóstico por imagem , Fístula Intestinal/mortalidade , Fístula Intestinal/cirurgia , Ligadura , Masculino , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Fístula Vascular/diagnóstico por imagem , Fístula Vascular/mortalidade , Fístula Vascular/cirurgia
8.
Vascular ; 29(5): 672-681, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33167798

RESUMO

OBJECTIVE: To report and analyze the indications and results of endovascular and open surgical treatment for uretero-arterial fistula. METHODS: We retrospectively reviewed the clinical data of 25 consecutive patients with uretero-arterial fistulas admitted to our hospital from 2011 to 2020. Endpoints were technical success, freedom from open conversion, stent-graft/graft-related complications, and 30-day and one-year mortality. RESULTS: The study included 25 patients (68% female, n = 17) with 27 uretero-arterial fistulas by bilateral pathologies in two patients. The mean age was 61 ± 11 years (range 35-80). The most common predisposing factors for uretero-arterial fistula were history of pelvic operations for malignancy in 21 patients (84%), radiotherapy in 21 patients (84%), previous pelvic vascular bypass in 2 patients (8%), and iliac aneurysms in 2 patients (8%). On average, the period between the primary pelvic surgery and the diagnosis of uretero-arterial fistulas was 46 months (range 7-255). Twenty patients (80%) underwent endovascular treatment of the uretero-arterial fistulas. The primary technical success of the endovascular treatment was 95%, and the freedom from open conversion was 40% at six months and 30% at one year. Thirteen uretero-arterial fistulas (48%) underwent delayed open conversion due to recurrent bleeding in six cases (46%), stent-graft infection in three cases (23%), or pelvic abscess in four cases (31%). Primary open surgery was applied for five (20%) patients. After a mean follow-up of 34 months, early (<30 days) mortality was 8% (2/25), one-year mortality 16% (4/25), and overall mortality was 24% (6/25). CONCLUSIONS: Uretero-arterial fistula is a late complication of prior pelvic surgery, radiation, and indwelling ureteral stents. Endovascular treatment remains an effective and less invasive modality in controlling the related life-threatening arterial bleeding of the uretero-arterial fistula. Open surgical treatment is still required for patients with local sepsis, previously failed endovascular treatment or infected stent-grafts.


Assuntos
Implante de Prótese Vascular , Procedimentos Endovasculares , Doenças Ureterais/cirurgia , Fístula Urinária/cirurgia , Fístula Vascular/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/mortalidade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/cirurgia , Reoperação , Estudos Retrospectivos , Stents , Fatores de Tempo , Resultado do Tratamento , Doenças Ureterais/diagnóstico por imagem , Doenças Ureterais/mortalidade , Fístula Urinária/diagnóstico por imagem , Fístula Urinária/mortalidade , Fístula Vascular/diagnóstico por imagem , Fístula Vascular/mortalidade
9.
Plant Cell ; 32(9): 2997-3018, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32616665

RESUMO

Cytidine-to-uridine RNA editing is a posttranscriptional process in plant organelles, mediated by specific pentatricopeptide repeat (PPR) proteins. In angiosperms, hundreds of sites undergo RNA editing. By contrast, only 13 sites are edited in the moss Physcomitrium (Physcomitrella) patens Some are conserved between the two species, like the mitochondrial editing site nad5eU598RC. The PPR proteins assigned to this editing site are known in both species: the DYW-type PPR protein PPR79 in P. patens and the E+-type PPR protein CWM1 in Arabidopsis (Arabidopsis thaliana). CWM1 also edits sites ccmCeU463RC, ccmBeU428SL, and nad5eU609VV. Here, we reciprocally expressed the P. patens and Arabidopsis editing factors in the respective other genetic environment. Surprisingly, the P. patens editing factor edited all target sites when expressed in the Arabidopsis cwm1 mutant background, even when carboxy-terminally truncated. Conversely, neither Arabidopsis CWM1 nor CWM1-PPR79 chimeras restored editing in P. patens ppr79 knockout plants. A CWM1-like PPR protein from the early diverging angiosperm macadamia (Macadamia integrifolia) features a complete DYW domain and fully rescued editing of nad5eU598RC when expressed in P. patens. We conclude that (1) the independently evolved P. patens editing factor PPR79 faithfully operates in the more complex Arabidopsis editing system, (2) truncated PPR79 recruits catalytic DYW domains in trans when expressed in Arabidopsis, and (3) the macadamia CWM1-like protein retains the capacity to work in the less complex P. patens editing environment.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Bryopsida/genética , Macadamia/genética , Proteínas Nucleares/metabolismo , Edição de RNA , Proteínas de Arabidopsis/genética , Evolução Molecular , Técnicas de Inativação de Genes , Teste de Complementação Genética , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Nucleares/genética , Filogenia , Plantas Geneticamente Modificadas , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
10.
Plants (Basel) ; 9(2)2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32098170

RESUMO

C to U editing is one of the post-transcriptional steps which are required for the proper expression of chloroplast and mitochondrial genes in plants. It depends on several proteins acting together which include the PLS-class pentatricopeptide repeat proteins (PPR). DYW2 was recently shown to be required for the editing of many sites in both organelles. In particular almost all the sites associated with the E+ subfamily of PPR proteins are depending on DYW2, suggesting that DYW2 is required for the function of E+-type PPR proteins. Here we strengthened this link by identifying 16 major editing sites controlled by 3 PPR proteins: OTP90, a DYW-type PPR and PGN and MEF37, 2 E+-type PPR proteins. A re-analysis of the DYW2 editotype showed that the 49 sites known to be associated with the 18 characterized E+-type PPR proteins all depend on DYW2. Considering only the 288 DYW2-dependent editing sites as potential E+-type PPR sites, instead of the 795 known editing sites, improves the performances of binding predictions systems based on the PPR code for E+-type PPR proteins. However, it does not compensate for poor binding predictions.

11.
Plant Physiol Biochem ; 135: 310-321, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30599308

RESUMO

In terrestrial plants, RNA editing converts specific cytidines to uridines in mitochondrial and plastidic transcripts. Most of these events appear to be important for proper function of organellar encoded genes, since translated proteins from edited mRNAs show higher similarity with evolutionary conserved polypeptide sequences. So far about 100 nuclear encoded proteins have been characterized as RNA editing factors in plant organelles. Respective RNA editing mutants reduce or lose editing activity at different sites and display various macroscopic phenotypes from pale or albino in the case of chloroplasts to growth retardation or even embryonic lethality. Therefore, RNA editing mutants can be a useful resource of surrogate mutants for organellar encoded genes, especially for mitochondrially encoded genes that it is so far unfeasible to manipulate. However, connections between RNA editing defects and observed phenotypes in the mutants are often hard to elucidate, since RNA editing factors often target multiple RNA sites in different genes simultaneously. In this review article, we summarize the physiological aspects of respective RNA editing mutants and discuss them as surrogate mutants for functional analysis of mitochondrially encoded genes.


Assuntos
Mitocôndrias/genética , Polimorfismo de Nucleotídeo Único/genética , Edição de RNA , Proteínas de Plantas/genética , Plantas/genética , Edição de RNA/genética
12.
Plant Cell Physiol ; 59(2): 355-365, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29216369

RESUMO

Pentatricopeptide repeat (PPR) proteins constitute the largest family of proteins in angiosperms, and most members are predicted to play roles in the maturation of organellar RNAs. Here we describe the novel mitochondrial editing factor 31 (MEF31), an E-PPR protein involved in editing at two close sites in the same transcript encoding subunit C of the twin-arginine translocation (tat) pathway. MEF31 is essential for editing at site tatC-581 and application of the recently proposed amino acid code for RNA recognition by PPR proteins supports the view that MEF31 directly targets this site by recognizing its cis sequence. In contrast, editing at site tatC-586 five nucleotides downstream is only partially affected in plants lacking MEF31, being restored to wild-type levels in complemented plants. Application of the amino acid code and analysis of individual RNA molecules for editing at sites 581 and 586 suggest that MEF31 does not directly target site tatC-586, and only indirectly influences editing at this site. It is likely that editing at site tatC-581 improves recognition of the site tatC-586 cis sequence by a second unknown PPR protein.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Cloroplastos/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Edição de RNA/genética , Proteínas de Ligação a RNA/genética , Sequência de Aminoácidos , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Sequência de Bases , Proteínas de Cloroplastos/química , Proteínas de Cloroplastos/metabolismo , Sequência Conservada/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , Modelos Biológicos , Mutação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Plântula/genética
13.
J Colloid Interface Sci ; 484: 237-248, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27619383

RESUMO

HYPOTHESIS: Many efforts have been made to formulate water-IL microemulsions. One of the most intensely studied systems is H2O - 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIm]PF6) - 4-octylphenol polyethoxylate (TX-100) and it is not questioned that this system forms microemulsions. The nanostructures observed for traditional microemulsions are postulated with the surfactant being adsorbed at the interface such that the hydrophilic EO sides intrude into the water domains, while the hydrophobic hydrocarbon chains are immersed into [BMIm]PF6. However, the high polarity of [BMIm]PF6 and the observation that [BMIm]PF6 mixes well with oligoethylene oxides but hardly with non-polar solvents like toluene or alkanes are not in line with this picture. EXPERIMENTS: We re-studied the ternary system H2O - [BMIm]PF6 - TX-100 by measuring phase diagrams, determining tie-lines, and carrying out ROESY NMR and PFG NMR measurements. FINDINGS: We found that the hydrophobic part of the surfactant interacts neither with water nor with [BMIm]PF6, while both solvents interact with the hydrophilic part of the surfactant. We suggest that the surfactant is not adsorbed at the interface between water and the IL, but forms normal spherical or elongated micelles or even continuous aggregates with the hydrocarbon chains forming the interior of the aggregates.

14.
Gut ; 63(2): 317-25, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23408352

RESUMO

BACKGROUND: As screening methods for colorectal cancer (CRC) are limited by uptake and adherence, further options are sought. A blood test might increase both, but none has yet been tested in a screening setting. OBJECTIVE: We prospectively assessed the accuracy of circulating methylated SEPT9 DNA (mSEPT9) for detecting CRC in a screening population. DESIGN: Asymptomatic individuals ≥50 years old scheduled for screening colonoscopy at 32 US and German clinics voluntarily gave blood plasma samples before colon preparation. Using a commercially available assay, three independent blinded laboratories assayed plasma DNA of all CRC cases and a stratified random sample of other subjects in duplicate real time PCRs. The primary outcomes measures were standardised for overall sensitivity and specificity estimates. RESULTS: 7941 men (45%) and women (55%), mean age 60 years, enrolled. Results from 53 CRC cases and from 1457 subjects without CRC yielded a standardised sensitivity of 48.2% (95% CI 32.4% to 63.6%; crude rate 50.9%); for CRC stages I-IV, values were 35.0%, 63.0%, 46.0% and 77.4%, respectively. Specificity was 91.5% (95% CI 89.7% to 93.1%; crude rate 91.4%). Sensitivity for advanced adenomas was low (11.2%). CONCLUSIONS: Our study using the blood based mSEPT9 test showed that CRC signal in blood can be detected in asymptomatic average risk individuals undergoing screening. However, the utility of the test for population screening for CRC will require improved sensitivity for detection of early cancers and advanced adenomas. CLINICAL TRIAL REGISTRATION NUMBER: NCT00855348.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Colorretais/sangue , Detecção Precoce de Câncer/métodos , Programas de Rastreamento/métodos , Septinas/sangue , Idoso , Neoplasias Colorretais/genética , Metilação de DNA , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Estados Unidos
15.
J Morphol ; 271(9): 1110-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20730923

RESUMO

The mechanism of sperm transfer in spiders is unique among arthropods. Males use their modified pedipalps to transmit sperm which is received by females of most spider groups in specialized organs, the receptacula seminis. Oonopidae are a diverse spider family belonging to the Haplogynae. Female haplogynes have supposedly simple genitalia where the receptacula derive from the uterus externus, which is the duct passed by the eggs. The purpose of the present study is to describe the unusual female genitalia of the oonopids Xyphinus sp. and Ischnothyreus sp. by combining three methods of investigation: histological serial sections, scanning electron microscopy, and X-ray ultra microscopy, and to compare the results with previous findings on haplogynes. Furthermore, the male palps are briefly described. The female genitalia of both investigated species do not correspond to the general description of haplogyne genitalia given in the literature. Distinct receptacula are lacking in both species. In Xyphinus sp., sperm are deposited into the uterus internus. A sclerite with attached muscles in the uterus wall might serve females to lock the uterus during copulation in order to prevent sperm from getting into it. The male palp of Xyphinus sp. bears complicated structures indicating that males could use the palps as copulatory courtship devices. The ventral scutum of female Ischnothyreus sp. forms a large depression which was always empty in the examined specimens. Sperm could be stored in a large fold of the uterus externus. As in Xyphinus sp., spermatozoa inside the uterus internus of Ischnothyreus sp. indicate that fertilization takes place in the uterus or the ovary. The function of a sclerotized squiggled tube in females of Ischnothyreus sp. remains unknown. Surrounding glandular tissue suggests the involvement of the tube in glandular activity. The male palp shows a simple embolus accompanied by a small conductor.


Assuntos
Aranhas/anatomia & histologia , Animais , Copulação/fisiologia , Feminino , Genitália Feminina/anatomia & histologia , Genitália Masculina/anatomia & histologia , Masculino , Preferência de Acasalamento Animal , Microscopia Eletrônica de Varredura
16.
J Mol Diagn ; 12(3): 345-53, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20304943

RESUMO

Prostate cancer is among the most common cancers. Although it has a relatively good prognosis, 15 to 30% of men with prostate cancer experience a relapse after radical prostatectomy. Identifying patients with an aggressive tumor will therefore help to improve prostate cancer management. DNA methylation of PITX2 has been established in several studies as a prognostic biomarker for breast and prostate cancer. These case control studies were conducted using research assay components; to facilitate its use in a diagnostic setting, the PITX2 biomarker was transferred to a validated diagnostic platform, the Affymetrix GeneChip System. A customized microarray (Epichip PITX2) was designed using features in high redundancy to ensure a robust determination of the methylation state of the PITX2 promoter. The developed method allowed for accurate assessment of prognosis in prostate cancer patients who underwent radical prostatectomy. Determination of PITX2 methylation in formalin-fixed and paraffin-embedded tissue samples from a cohort of 157 prostatectomy patients resulted in an excellent level of concordance of the clinical classification, as well as the measured output between the research assay and the Epichip PITX2. These analytical performance results describe the Epichip PITX2 as a robust and reliable diagnostic tool for assessing the methylation status of PITX2, enabling an improved outcome prediction in cancer patients following radical prostatectomy.


Assuntos
Metilação de DNA/genética , Proteínas de Homeodomínio/genética , Neoplasias da Próstata/genética , Fatores de Transcrição/genética , Humanos , Estimativa de Kaplan-Meier , Masculino , Reação em Cadeia da Polimerase , Prostatectomia , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia
17.
Zoology (Jena) ; 113(2): 100-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20138745

RESUMO

The unusual reproductive biology of many spider species makes them compelling targets for evolutionary investigations. Mating behavior studies combined with genital morphological investigations help to understand complex spider reproductive systems and explain their function in the context of sexual selection. Oonopidae are a diverse spider family comprising a variety of species with complex internal female genitalia. Data on oonopid phylogeny are preliminary and especially studies on their mating behavior are very rare. The present investigation reports on the copulatory behavior of an Orchestina species for the first time. The female genitalia are described by means of serial semi-thin sections and scanning electron microscopy. Females of Orchestina sp. mate with multiple males. On average, copulations last between 15.4 and 23.54min. During copulation, the spiders are in a position taken by most theraphosids and certain members of the subfamily Oonopinae: the male pushes the female back and is situated under her facing the female's sternum. Males of Orchestina sp. possibly display post-copulatory mate-guarding behavior. The female genitalia are complex. The genital opening leads into the uterus externus from which a single receptaculum emerges. The dorsal wall of the receptaculum forms a sclerite serving as muscle attachment. A sclerotized plate with attached muscles lies in the posterior wall of the uterus externus. The plate might be used to lock the uterus during copulation. The present study gives no direct evidence for cryptic female choice in Orchestina sp. but suggests that sexual selection occurs in the form of sperm competition through sperm mixing.


Assuntos
Comportamento Sexual Animal , Aranhas/ultraestrutura , Animais , Feminino , Genitália Feminina/ultraestrutura , Genitália Masculina/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura
19.
Zoology (Jena) ; 113(1): 19-32, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19939658

RESUMO

In promiscuous females, sperm ejection from the sperm storage site can be a strong mechanism to influence sperm priority patterns. Sperm dumping is reported from different animals including birds, insects, and humans. In spiders, it has been documented for four species including the oonopid Silhouettella loricatula. Oonopidae are a diverse spider family comprising many species with peculiar female genitalia. Especially in species where studies of mating behavior are difficult, morphological investigations of the genitalia help to understand their function and evolution. In the present study, the genitalia of the oonopids Myrmopopaea sp., Grymeus sp., and Lionneta sp. are investigated by means of histological serial sections and scanning electron microscopy (SEM). The results are compared with previous findings on S. loricatula. In Myrmopopaea sp. and Grymeus sp., the same morphological components are present that are involved in sperm dumping in S. loricatula. Inside the receptaculum, sperm are enclosed in a secretory sac which can be moved to the genital opening and dumped during copulation by muscle contractions. The female genitalia of Lionneta sp. are asymmetric. They show the same characteristics as S. loricatula but all the investigated females were unmated. The results strongly suggest that sperm dumping occurs in Myrmopopaea sp., Grymeus sp., and Lionneta sp. and happens by the same mechanism as in S. loricatula. Sperm dumping might even be common within a clade of oonopids. As in S. loricatula, the sperm transfer forms in the investigated species consist of several spermatozoa. Papillae with unknown function occur on the receptacula of all females.


Assuntos
Genitália Feminina/fisiologia , Espermatozoides/fisiologia , Aranhas/fisiologia , Animais , Copulação/fisiologia , Feminino , Fertilização/fisiologia , Genitália Feminina/anatomia & histologia , Genitália Feminina/ultraestrutura , Genitália Masculina/anatomia & histologia , Genitália Masculina/fisiologia , Genitália Masculina/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Reprodução/fisiologia , Comportamento Sexual Animal/fisiologia , Útero/anatomia & histologia , Útero/fisiologia
20.
J Morphol ; 269(9): 1073-94, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18563703

RESUMO

This study describes the female genitalia of the tetrablemmid spiders Brignoliella acuminata, Monoblemma muchmorei, Caraimatta sbordonii, Tetrablemma magister, and Ablemma unicornis by means of serial semi-thin sections and scanning electron microscopy and compares the results with previous findings on Indicoblemma lannaianum. Furthermore, the male palps and chelicerae are briefly described. The general vulval organization of females is complex and shows similarities in all of the investigated species. The copulatory orifice is situated near the posterior margin of the pulmonary plate. The opening of the uterus externus lies between the pulmonary and the postgenital plate. Paired copulatory ducts lead to sac-like receptacula. Except for A. unicornis, the male emboli of all investigated species are elongated and thread-like. However, they are too short to reach the receptacula. Hence, the spermatozoa have to be deposited inside the copulatory ducts. The same situation was also found in I. lannaianum. Females of this species store sperm encapsulated in secretory balls in their receptacula. The secretion is produced by glands adjoining the receptacula. The presence of paired fertilization ducts and spermatozoa in the uterus internus suggested that fertilization takes place internally in I. lannaianum. Secretory balls in the receptacula are found in all of the investigated species in this study, showing that sperm are stored in the same way. The place of fertilization may also be identical since dark particles, presumably spermatozoa, are located in the uterus internus of all investigated species except for T. magister. However, fertilization ducts are only found in B. acuminata and M. muchmorei. A sclerotized central process with attached muscles is present in A. unicornis, M. muchmorei, C. sbordonii and T. magister. Only in A. unicornis does the central process show an internal lumen and hold spermatozoa. In the other species, it could be used to lock the uterus during copulation in order to prevent sperm from getting into it as suggested for certain oonopid species. The uterus externus of all investigated species shows a sclerotized dorsal fold with attached muscles, previously described as "inner vulval plate." Contractions of the muscles lead to a widening of the dorsal fold, thus creating enough space for the large oocytes to pass the narrow uterus externus. The males of all investigated species have apophyses on their chelicerae. At least in B. acuminata and A. unicornis, where females have paired grooves on the preanal plate, these apophyses allow males to grasp the female during copulation as described for I. lannaianum.


Assuntos
Aranhas/anatomia & histologia , Animais , Copulação , Feminino , Fertilização , Genitália/anatomia & histologia , Genitália/citologia , Genitália/fisiologia , Genitália/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Aranhas/citologia , Aranhas/fisiologia , Aranhas/ultraestrutura , Útero/anatomia & histologia , Útero/fisiologia , Útero/ultraestrutura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...