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This comprehensive Review delves into the chemical principles governing RNA-mediated crowding events, commonly referred to as granules or biological condensates. We explore the pivotal role played by RNA sequence, structure, and chemical modifications in these processes, uncovering their correlation with crowding phenomena under physiological conditions. Additionally, we investigate instances where crowding deviates from its intended function, leading to pathological consequences. By deepening our understanding of the delicate balance that governs molecular crowding driven by RNA and its implications for cellular homeostasis, we aim to shed light on this intriguing area of research. Our exploration extends to the methodologies employed to decipher the composition and structural intricacies of RNA granules, offering a comprehensive overview of the techniques used to characterize them, including relevant computational approaches. Through two detailed examples highlighting the significance of noncoding RNAs, NEAT1 and XIST, in the formation of phase-separated assemblies and their influence on the cellular landscape, we emphasize their crucial role in cellular organization and function. By elucidating the chemical underpinnings of RNA-mediated molecular crowding, investigating the role of modifications, structures, and composition of RNA granules, and exploring both physiological and aberrant phase separation phenomena, this Review provides a multifaceted understanding of the intriguing world of RNA-mediated biological condensates.
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RNA , RNA/química , RNA/metabolismo , Humanos , Substâncias Macromoleculares/química , Substâncias Macromoleculares/metabolismo , Animais , Conformação de Ácido NucleicoRESUMO
SUMMARY: Biological condensates are membraneless organelles with different material properties. Proteins and RNAs are the main components, but most of their interactions are still unknown. Here, we introduce PRALINE, a database for the interrogation of proteins and RNAs contained in stress granules, processing bodies and other assemblies including droplets and amyloids. PRALINE provides information about the predicted and experimentally validated protein-protein, protein-RNA and RNA-RNA interactions. For proteins, it reports the liquid-liquid phase separation and liquid-solid phase separation propensities. For RNAs, it provides information on predicted secondary structure content. PRALINE shows detailed information on human single-nucleotide variants, their clinical significance and presence in protein and RNA binding sites, and how they can affect condensates' physical properties. AVAILABILITY AND IMPLEMENTATION: PRALINE is freely accessible on the web at http://praline.tartaglialab.com.
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Organelas , RNA , Humanos , RNA/metabolismo , Proteínas/metabolismo , Nucleotídeos/metabolismoRESUMO
BACKGROUND: Sentinel lymph node (SLN) biopsy for cN+ breast cancer patients after neoadjuvant chemotherapy (NAC) is controversial because the false-negative rate (FNR) is high. Identification of three or more SLNs with a dual tracer improves these results, and inclusion of a clipped lymph node (CLN) (targeted axillary dissection [TAD]) may be even more effective. METHODS: A retrospective, single-institution analysis of consecutive cN+ patients undergoing NAC from 2019 to 2021 was performed. Patients routinely underwent placement of a clip in the positive lymph node before NAC, and TAD was performed after completion of therapy. RESULTS: The study analyzed 73 patients, and the identification rate for CLN was 98.6% (72/73). A complete response in the lymph nodes was achieved for 43 (59%) of the 73 patients. Overall, the CLN was not a SLN in 18 (25%) of 73 cases, and for women who had one or two and those who had three or more SLNs identified, this occurred in 11 (32%) and 7 (21%) of 34 cases, respectively. Failure of SLN or TAD to identify a positive residual lymph node status after NAC occurred in 10 (15%) of 69 and 2 (3%) of 73 cases, respectively (p = 0.01). In four cases, a SLN was not retrieved (5.5%), and two of these cases had a positive CLN. In three cases, the CLN was the only positive node and did not match with a SLN, directing lymphadenectomy and oncologic management change in two cases. Therefore, 7 (10%) of 73 cases had a change in surgical or oncologic management with TAD. CONCLUSIONS: For a conservative axillary treatment in this setting, TAD is an effective method. It is more accurate than SLN alone and allows management changes. Further studies are warranted.
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Neoplasias da Mama , Linfonodo Sentinela , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Terapia Neoadjuvante/métodos , Estudos Retrospectivos , Metástase Linfática/patologia , Reações Falso-Negativas , Biópsia de Linfonodo Sentinela/métodos , Linfonodos/cirurgia , Linfonodos/patologia , Excisão de Linfonodo/métodos , Axila/patologia , Estadiamento de Neoplasias , Linfonodo Sentinela/patologiaRESUMO
RNA molecules undergo a number of chemical modifications whose effects can alter their structure and molecular interactions. Previous studies have shown that RNA editing can impact the formation of ribonucleoprotein complexes and influence the assembly of membrane-less organelles such as stress granules. For instance, N6-methyladenosine (m6A) enhances SG formation and N1-methyladenosine (m1A) prevents their transition to solid-like aggregates. Yet, very little is known about adenosine to inosine (A-to-I) modification that is very abundant in human cells and not only impacts mRNAs but also noncoding RNAs. Here, we introduce the CROSSalive predictor of A-to-I effects on RNA structure based on high-throughput in-cell experiments. Our method shows an accuracy of 90% in predicting the single and double-stranded content of transcripts and identifies a general enrichment of double-stranded regions caused by A-to-I in long intergenic noncoding RNAs (lincRNAs). For the individual cases of NEAT1, NORAD, and XIST, we investigated the relationship between A-to-I editing and interactions with RNA-binding proteins using available CLIP data and catRAPID predictions. We found that A-to-I editing is linked to the alteration of interaction sites with proteins involved in phase separation, which suggests that RNP assembly can be influenced by A-to-I. CROSSalive is available at http://service.tartaglialab.com/new_submission/crossalive.
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Adenosina , RNA Longo não Codificante , Humanos , Adenosina/química , RNA não Traduzido/genética , RNA Mensageiro/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Inosina/metabolismoRESUMO
BACKGROUND: Nipple-sparing mastectomy (NSM) is increasingly used for women with breast cancer who are not candidates for conservative surgery. The authors previously reported satisfying results with NSM after neoadjuvant chemotherapy (NACT). METHODS: From 2010 to 2020, 1072 women underwent mastectomy at the authors' institution. In this group, 433 NSMs were performed (40%). The only contraindications to NSM were close proximity to the nipple-areola complex (NAC), bloody discharge, and Paget disease. RESULTS: In 112 cases involving 111 women, NSM followed NACT (group 1), whereas it was performed as primary surgery in 321 instances involving 306 women (group 2). At 5 years, local relapse was 7% in group 1 and 2% in group 2, although in the multivariate analysis, locoregional relapses (LRRs) did not differ between the two groups. An increased incidence of local relapse was associated with higher tumor stage (stage III; p = 0.046) and age younger than 51 years (p = 0.038). For 34 (30.3%) of the 111 women in group 1 with a pathologic complete response (pCR), no LRRs were recorded. Only one NAC recurrence was observed. Overall survival with each tumor stage did not differ between the two groups. No differences in complications were observed. Cosmetic results were satisfying in 83.8% of the cases and did not get worse after NACT. CONCLUSIONS: The study data definitively confirm that NSM is safe even after NACT, with good cosmetic results and complications comparable with those in the primary surgery setting. Tumor stage and age were the only independent factors for local relapse. Patients with pCR enjoyed optimal locoregional control.
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Neoplasias da Mama , Mamoplastia , Mastectomia Subcutânea , Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Mastectomia/métodos , Terapia Neoadjuvante , Mamilos/cirurgia , Mamilos/patologia , Seguimentos , Estudos Retrospectivos , Recidiva Local de Neoplasia/patologia , Mastectomia Subcutânea/métodos , Mamoplastia/métodosRESUMO
BACKGROUND: Intraoperative examination of retro-areolar margin (IERM) often is used during nipple-sparing mastectomy (NSM) for cancer, but there is no robust data regarding its real advantage. METHODS: Consecutive patients undergoing NSM for cancer with omission of IERM according to institutional protocols from 2016 to 2021 were retrospectively analyzed. The decision to maintain or remove the Nipple-Areola Complex (NAC) after definitive pathology was taken at the multidisciplinary meeting. RESULTS: Among 162 women operated in the study period, the presence of neoplastic cells within 2 mm from the inked retroareolar margin (RAM) was detected at permanent pathology in 17 cases (10.5%). Nipple-Areola-Complex (NAC) was removed postoperatively in five patients (3%) for margins <1 mm, the other 12 were observed, whereas postoperative NAC necrosis required surgical removal in additional five cases (3%). The NAC was thus preserved in 152 of 162 patients (94%). At multivariate analysis, RAM ≤2 mm was associated with radiological tumor-to-nipple distance less than or equal to 1 cm (p = 0.04) and Ki67 label index ≥ 20 (p = 0.04), whereas multifocality/multicentricity showed a trend towards significance (p = 0.07). At a median follow-up of 46 months, five locoregional relapses occurred (3%), only one of them involving the NAC (0, 6%). Locoregional relapse and overall survival for patients with RAM > or < 2 mm were not different. CONCLUSIONS: IERM is not routinely necessary during NSM for cancer, because its omission is associated with a very low return to the operating room, it is oncologically safe, and associated pitfalls are avoided. Further studies are necessary to confirm these findings.
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Neoplasias da Mama , Mamoplastia , Mastectomia Subcutânea , Humanos , Feminino , Mastectomia/métodos , Mamilos/cirurgia , Mamilos/patologia , Estudos Retrospectivos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologiaRESUMO
A better understanding of transcriptional and post-transcriptional regulation of gene expression in bacteria relies on studying their transcriptome. RNA sequencing methods are used not only to assess RNA abundance but also the exact boundaries of primary and processed transcripts. Here, we developed a method, called identification of specific cleavage position (ISCP), which enables the identification of direct endoribonuclease targets in vivo by comparing the 5Î and 3Î ends of processed transcripts between wild type and RNase deficient strains. To demonstrate the ISCP method, we used as a model the double-stranded specific RNase III in the human pathogen Streptococcus pyogenes. We mapped 92 specific cleavage positions (SCPs) among which, 48 were previously described and 44 are new, with the characteristic 2 nucleotides 3Î overhang of RNase III. Most SCPs were located in untranslated regions of RNAs. We screened for RNase III targets using transcriptomic differential expression analysis (DEA) and compared those with the RNase III targets identified using the ISCP method. Our study shows that in S. pyogenes, under standard growth conditions, RNase III has a limited impact both on antisense transcripts and on global gene expression with the expression of most of the affected genes being downregulated in an RNase III deletion mutant.
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Regulação Bacteriana da Expressão Gênica , RNA Antissenso/genética , RNA Bacteriano/genética , Ribonuclease III/genética , Streptococcus pyogenes/genética , Proteínas de Bactérias , Pareamento de Bases , Sequência de Bases , Deleção de Genes , Conformação de Ácido Nucleico , Clivagem do RNA , RNA Antissenso/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribonuclease III/deficiência , Streptococcus pyogenes/metabolismo , Transcriptoma , Regiões não TraduzidasRESUMO
Endoribonuclease Y (RNase Y) is a crucial regulator of virulence in Gram-positive bacteria. In the human pathogen Streptococcus pyogenes, RNase Y is required for the expression of the major secreted virulence factor streptococcal pyrogenic exotoxin B (SpeB), but the mechanism involved in this regulation remains elusive. Here, we demonstrate that the 5' untranslated region of speB mRNA is processed by several RNases including RNase Y. In particular, we identify two RNase Y cleavage sites located downstream of a guanosine (G) residue. To assess whether this nucleotide is required for RNase Y activity in vivo, we mutated it and demonstrate that the presence of this G residue is essential for the processing of the speB mRNA 5' UTR by RNase Y. Although RNase Y directly targets and processes speB, we show that RNase Y-mediated regulation of speB expression occurs primarily at the transcriptional level and independently of the processing in the speB mRNA 5' UTR. To conclude, we demonstrate for the first time that RNase Y processing of an mRNA target requires the presence of a G. We also provide new insights on the speB 5' UTR and on the role of RNase Y in speB regulation.
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Proteínas de Bactérias/genética , Exotoxinas/genética , Ribonucleases/genética , Infecções Estreptocócicas/genética , Streptococcus pyogenes/genética , Regiões 5' não Traduzidas/genética , Sequência de Aminoácidos/genética , Regulação Bacteriana da Expressão Gênica/genética , Guanosina/metabolismo , Humanos , Infecções Estreptocócicas/metabolismo , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/patogenicidade , Fatores de Virulência/genéticaRESUMO
Introduction: Scarless latissimus dorsi (LD) flap is a breast reconstruction technique, which allow to cover the lower pole of implant with a large portion of the LD muscle without skin paddle; it represents a surgical solution that transpose vascularized tissue avoiding the failure of breast reconstruction, following necrosis of mastectomy skin flaps. Material and Method: A retrospective review of patients undergoing immediate or delayed breast reconstruction using scarless LD flap reconstructions was performed. Clinical data obtained from follow-up visits were recorded. To evaluate breast shape contentment and patient satisfaction, the patients were requested to answer the Breast-Q, version 2.0 reduction module postoperative scales questionnaire at the 12-month follow-up. Results: We performed 19 scarless LD flap reconstructions between September 2019 and June 2022. The surgical time in average (considering minutes ± SD) was 130 (±15) minutes. The aesthetic assessment was good/excellent in 83% of patients. This was statistically significant (P=0.0). Conclusions: The scarless LD flap reconstruction is a valid and reliable solution, which has the advantage to reduce the risk of exposed prosthesis if native skin necrosis occurs.
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Bacteria adjust gene expression at the post-transcriptional level through an intricate network of small regulatory RNAs and RNA-binding proteins, including ribonucleases (RNases). RNases play an essential role in RNA metabolism, regulating RNA stability, decay, and activation. These enzymes exhibit species-specific effects on gene expression, bacterial physiology, and different strategies of target recognition. Recent advances in high-throughput RNA sequencing (RNA-seq) approaches have provided a better understanding of the roles and modes of action of bacterial RNases. Global studies aiming to identify direct targets of RNases have highlighted the diversity of RNase activity and RNA-based mechanisms of gene expression regulation. Here, we review recent RNA-seq approaches used to study bacterial RNases, with a focus on the methods for identifying direct RNase targets.
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Endorribonucleases , Ribonucleases , Ribonucleases/genética , RNA-Seq , Bactérias/genética , RNARESUMO
PURPOSE: We report long-term outcomes of phase 2 trial on patients with invasive breast cancer treated with accelerated partial-breast irradiation (APBI) using tomotherapy after breast conservative surgery. METHODS AND MATERIALS: From December 2010 to December 2018, we treated 338 women with APBI-tomotherapy: 38.5 Gy in 10 once-daily fractions. Patients selected were age ≥50 years old, with ≤3 cm in size unifocal tumor and at least 2 mm of clear margins. Disease outcomes were analyzed by clinicopathologic characteristics, molecular phenotypes, and American Society for Radiation Oncology (ASTRO) 2017 updated consensus groupings. RESULTS: The median age was 65 years (range, 50-86). The invasive ductal (87.5%) and the luminal A-like molecular phenotype (70%) were the most common tumors. Overall 242 patients (71.6%) were considered "suitable" for enrollment in APBI according to the eligibility criteria of the ASTRO-2017 consensus statement. With a median follow-up of 76 months (range, 17-113), 2 patients (0.6%) had an invasive ipsilateral breast tumor recurrence (IBTR), and 2 patients (0.6%) had an axillary ipsilateral failure. The rate of local control in terms of free of IBTR was 99.4% and locoregional control (no recurrence in ipsilateral breast as well as in regional nodes) was 98.8%. Progression-free survival was 98.4% and 92% at 5 and 10 years, respectively. Acute and late skin toxicity, graded according to the Common Terminology Criteria for Adverse Events, were 7.7% (G1) and 0.6% (G2) and 4.4% (G1) and 1.1% (G2), respectively. There were no grade 3/4 toxicities, however. Very few patients (2%) or physicians (2%) assessed cosmetic outcome as fair or poor at the 2-year follow-up. CONCLUSIONS: This phase 2 trial on APBI-tomotherapy shows excellent long-term results. Once-daily fractionation schedule was well tolerated with a low rate of adverse events and worse cosmetic outcome. In this series, even among those deemed cautionary or unsuitable for APBI by ASTRO criteria, we demonstrated a low rate of IBTR.
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Neoplasias da Mama/radioterapia , Carcinoma Ductal de Mama/radioterapia , Carcinoma Lobular/radioterapia , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/patologia , Carcinoma Lobular/cirurgia , Consenso , Fracionamento da Dose de Radiação , Estética , Feminino , Humanos , Estimativa de Kaplan-Meier , Margens de Excisão , Mastectomia Segmentar , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Intervalo Livre de Progressão , Radioterapia/métodos , Radioterapia de Intensidade Modulada , Fatores de Tempo , Resultado do TratamentoRESUMO
RNA degradation is an essential process that allows bacteria to control gene expression and adapt to various environmental conditions. It is usually initiated by endoribonucleases (endoRNases), which produce intermediate fragments that are subsequently degraded by exoribonucleases (exoRNases). However, global studies of the coordinated action of these enzymes are lacking. Here, we compare the targetome of endoRNase Y with the targetomes of 3'-to-5' exoRNases from Streptococcus pyogenes, namely, PNPase, YhaM, and RNase R. We observe that RNase Y preferentially cleaves after guanosine, generating substrate RNAs for the 3'-to-5' exoRNases. We demonstrate that RNase Y processing is followed by trimming of the newly generated 3' ends by PNPase and YhaM. Conversely, the RNA 5' ends produced by RNase Y are rarely further trimmed. Our strategy enables the identification of processing events that are otherwise undetectable. Importantly, this approach allows investigation of the intricate interplay between endo- and exoRNases on a genome-wide scale.
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Exorribonucleases/metabolismo , RNA-Seq , Transcriptoma/genética , Regiões 5' não Traduzidas/genética , Sequência de Bases , Regulação Bacteriana da Expressão Gênica , Guanosina/metabolismo , Óperon/genética , Estabilidade de RNA/genética , Streptococcus pyogenes/genéticaRESUMO
BACKGROUND: Capsular contracture (CC) is the most common complication following Immediate Breast Reconstruction (IBR) with breast implants. Different implant surfaces were developed aiming to reduce the incidence of CC. We evaluated the incidence and degree of CC after Direct-to-Implant (DTI) IBR with insertion of textured (TE) or polyurethane (PU) covered implants. METHODS: A retrospective review of consecutive patients treated at our Institution with mastectomy and one-stage IBR and implant reconstruction between 2013 and 2018, with or without post mastectomy radiation therapy (PMRT), was conducted. Immediate breast reconstruction was performed by implanting 186 PU covered implants and 172 TE implants. RESULTS: Three-hundred-twelve women underwent 358 DTI IBR with PU or TE implants, were analyzed with a median follow-up time of 2.3 years (range 1.0-3.0). The overall rate of CC Baker grade III and IV was 11.8% (95%CI: 8.4-16.3), while, after PU and TE implant placement it was 8.1% (95% CI: 4.1-15.7) and 15.8% (95% CI: 4.1-15.7) [p = 0.009]), respectively. Irradiated breasts developed CC more frequently rather than non-irradiated breasts (HR = 12.5, p < 0.001), and the relative risk was higher in the TE group compared with the PU group (HR = 0.3, p = 0.003). CONCLUSIONS: After mastectomy and one-stage IBR, the use of PU covered implants is associated with a lower incidence of CC compared to TE implants. This advantage is amplified several folds for patients who necessitate PMRT. Footnote: Capsular contracture (CC); Immediate Breast Reconstruction (IBR); Directto- Implant (DTI); Textured (TE); Polyurethane (PU); Post mastectomy radiation therapy (PMRT); Nipple Sparing mastectomy (NSM).
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Implante Mamário/efeitos adversos , Implantes de Mama/efeitos adversos , Neoplasias da Mama/cirurgia , Contratura Capsular em Implantes/epidemiologia , Desenho de Prótese/efeitos adversos , Adulto , Implante Mamário/métodos , Feminino , Humanos , Contratura Capsular em Implantes/etiologia , Incidência , Mastectomia/métodos , Pessoa de Meia-Idade , Poliuretanos , Estudos Retrospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Pleomorphic invasive lobular carcinoma (P-ILC) is an uncommon variety of invasive lobular carcinoma with aggressive clinical features. Little is described in the literature regarding this topic. MATERIALS AND METHODS: We reviewed our experiences from 2010 to 2015 and compared 40 patients with P-ILC, 126 patients with classic-ILC (C-ILC) and 574 cases of high-grade invasive ductal carcinoma (HG-IDC). We studied the histologic and immunohistochemical features, clinical presentation and surgical treatment. RESULTS: P-ILC is diagnosed at the same age and tumor diameter as those of the other two histologic types. It is associated more frequently with multiple lymph node metastases and high proliferative index, and HER2/neu is amplified in 10% of cases. In spite of sharing some histologic characteristics with C-ILC (same growth pattern, loss of E-cadherin expression, same genetic pathway), its clinical and pathologic features define an autonomous entity. Its surgical treatment is similar to those of C-ILC and HG-IDC. CONCLUSION: This is the first review comparing these three pathologic entities. Our findings may be useful in understanding this variety of invasive lobular carcinoma, and further studies are certainly needed in this field.
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BACKGROUND: Late migration of a plastic biliary stent after endoscopic placement is a well known complication, but there is little information regarding migration of a plastic stent during multiple stents placement. CASE REPORT: A white man was hospitalized for severe jaundice due to neoplastic hilar stenosis. Surgical eligibility appeared unclear on admission and endoscopy was carried out, but the first stent migrated proximally at the time of second stent insertion. After failed attempts with various devices, the migrated stent was removed successfully through cannulation with a dilation balloon. CONCLUSIONS: The migration of a plastic biliary stent during multiple stents placement is a possible complication. In this context, extraction can be very complicated. In our patient, cannulation of a stent with a dilation balloon was the only effective method.
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Remoção de Dispositivo/instrumentação , Remoção de Dispositivo/métodos , Migração de Corpo Estranho/cirurgia , Stents/efeitos adversos , Idoso , Colangiopancreatografia Retrógrada Endoscópica , Colestase Intra-Hepática/cirurgia , Humanos , MasculinoRESUMO
Colonic gallstone ileus in an uncommon mechanical bowel obstruction caused by intraluminal impaction of one or more gallstones. The surgical management of gallstone ileus is complex and is potentially of high risk. There have been reports of gallstone extractions using various endoscopic modalities to relieve the obstruction. In this report we present the technique employed to successfully perform a mechanical lithotripsy and extraction of a large gallstone embedded in a sigmoid colon affected by diverticular stenosis. We passed through the stenosis with a 11.3 mm videoscope with 3.7 mm channel. A large lithotripsy extraction basket was used to catch and break up the stone and fragments were removed using the same basket. The patient was discharged asymptomatic three days after the procedure. Using appropriate devices mechanical lithotripsy is a safe and effective method to treat colonic obstruction and avoid surgery in the setting of gallstone ileus even in case of big stones.
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Pseudomembranous collagenous colitis is a rare pathological condition, not related to infectious agents, and characterized by thickening of the subepithelial collagen and formation of pseudomembranes. We report one such case, which responded to budesonide treatment after failures of previous approaches given, being unaware of the correct diagnosis.
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Colite Colagenosa/patologia , Colo/patologia , Enterocolite Pseudomembranosa/patologia , Idoso , Biópsia , Budesonida/uso terapêutico , Resina de Colestiramina/efeitos adversos , Colite Colagenosa/tratamento farmacológico , Colo/efeitos dos fármacos , Colonoscopia , Enterocolite Pseudomembranosa/tratamento farmacológico , Feminino , Glucocorticoides/uso terapêutico , Humanos , Valor Preditivo dos Testes , Resultado do TratamentoRESUMO
The development of imaging techniques for the non-invasive detection of atherosclerosis answered the specific need of identifying vulnerable plaque in asymptomatic patients, verify the presence of atherosclerosis in patients at intermediate risk of coronary artery disease and, lastly, evaluate the results of previous coronary interventions. Coronary computed tomography angiography is the non-invasive technique that has been most widely used for these purposes. The technique mainly focuses on the presence of calcium in the walls of the coronary arteries. Whether or not coronary arterial calcification is part of the development of atherosclerosis, it occurs in small amounts in the early lesions and is found more frequently in advanced lesions and at an older age. Plaques rich in collagen and calcium, which can be depicted by coronary calcium scoring, are widely considered firm and stable, whereas soft atheromas containing a core of lipids and necrotic debris that are biologically "unstable" and therefore prone to rupture, cannot be visualised by calcium scoring or correctly assessed by coronary computed tomography angiography. In fact, the relation of arterial calcification to the probability of plaque rupture is unknown. There is no definite relationship between vulnerable plaque and coronary artery calcification in comparative studies with intravascular ultrasound. On the other hand, radiographically detected coronary artery calcium can provide an estimate of total coronary plaque burden but, due to arterial remodelling, calcium does not concentrate exclusively at sites with severe coronary artery stenoses. In any event, this technique has great potential for identification of atherosclerosis. A more established use of coronary computed tomography angiography is in the evaluation of patients after coronary interventions. The future also holds promise for imaging coronary artery atherosclerotic plaques using magnetic resonance. At the present time, the differentiation of coronary plaque components with magnetic resonance is limited by inadequate spatial resolution; however, promising research is ongoing and the role of magnetic resonance in the evaluation of patients with coronary artery disease will continue to grow as its utility and prognostic importance will be further defined.