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Mitochondrial RNA polymerase (mtRNAP) is crucial in cellular energy production, yet understanding of mitochondrial DNA transcription initiation lags that of bacterial and nuclear DNA transcription. We report structures of two transcription initiation intermediate states of yeast mtRNAP that explain promoter melting, template alignment, DNA scrunching, abortive synthesis, and transition into elongation. In the partially melted initiation complex (PmIC), transcription factor MTF1 makes base-specific interactions with flipped non-template (NT) nucleotides "AAGT" at -4 to -1 positions of the DNA promoter. In the initiation complex (IC), the template in the expanded 7-mer bubble positions the RNA and NTP analog UTPαS, while NT scrunches into an NT loop. The scrunched NT loop is stabilized by the centrally positioned MTF1 C-tail. The IC and PmIC states coexist in solution, revealing a dynamic equilibrium between two functional states. Frequent scrunching/unscruching transitions and the imminent steric clashes of the inflating NT loop and growing RNA:DNA with the C-tail explain abortive synthesis and transition into elongation.
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DNA Mitocondrial/genética , RNA Polimerases Dirigidas por DNA/genética , Mitocôndrias/genética , Proteínas Mitocondriais/genética , RNA Mitocondrial/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , Sítios de Ligação , Microscopia Crioeletrônica , DNA Mitocondrial/química , DNA Mitocondrial/metabolismo , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , Modelos Moleculares , Motivos de Nucleotídeos , Regiões Promotoras Genéticas , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , RNA Mitocondrial/química , RNA Mitocondrial/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Termodinâmica , Elongação da Transcrição Genética , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Iniciação da Transcrição GenéticaRESUMO
Structures trapping a variety of functional and conformational states of HIV-1 reverse transcriptase (RT) have been determined by X-ray crystallography. These structures have played important roles in explaining the mechanisms of catalysis, inhibition, and drug resistance and in driving drug design. However, structures of several desired complexes of RT could not be obtained even after many crystallization or crystal soaking experiments. The ternary complexes of doravirine and rilpivirine with RT/DNA are such examples. Structural study of HIV-1 RT by single-particle cryo-electron microscopy (cryo-EM) has been challenging due to the enzyme's relatively smaller size and higher flexibility. We optimized a protocol for rapid structure determination of RT complexes by cryo-EM and determined six structures of wild-type and E138K/M184I mutant RT/DNA in complexes with the nonnucleoside inhibitors rilpivirine, doravirine, and nevirapine. RT/DNA/rilpivirine and RT/DNA/doravirine complexes have structural differences between them and differ from the typical conformation of nonnucleoside RT inhibitor (NNRTI)-bound RT/double-stranded DNA (dsDNA), RT/RNA-DNA, and RT/dsRNA complexes; the primer grip in RT/DNA/doravirine and the YMDD motif in RT/DNA/rilpivirine have large shifts. The DNA primer 3'-end in the doravirine-bound structure is positioned at the active site, but the complex is in a nonproductive state. In the mutant RT/DNA/rilpivirine structure, I184 is stacked with the DNA such that their relative positioning can influence rilpivirine in the pocket. Simultaneously, E138K mutation opens the NNRTI-binding pocket entrance, potentially contributing to a faster rate of rilpivirine dissociation by E138K/M184I mutant RT, as reported by an earlier kinetic study. These structural differences have implications for understanding molecular mechanisms of drug resistance and for drug design.
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Fármacos Anti-HIV , Farmacorresistência Viral , Transcriptase Reversa do HIV , HIV-1 , Piridonas , Inibidores da Transcriptase Reversa , Rilpivirina , Triazóis , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Microscopia Crioeletrônica , Farmacorresistência Viral/genética , Transcriptase Reversa do HIV/antagonistas & inibidores , Transcriptase Reversa do HIV/química , Transcriptase Reversa do HIV/genética , HIV-1/enzimologia , Mutação , Nitrilas/farmacologia , Conformação Proteica , Piridonas/química , Piridonas/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/farmacologia , Rilpivirina/química , Rilpivirina/farmacologia , Triazóis/química , Triazóis/farmacologiaRESUMO
Hepatocellular carcinoma (HCC) typically develops as a consequence of liver cirrhosis, but HCC epidemiology has evolved drastically in recent years. Metabolic dysfunction-associated steatotic liver disease (MASLD), including metabolic dysfunction-associated steatohepatitis, has emerged as the most common chronic liver disease worldwide and a leading cause of HCC. A substantial proportion of MASLD-associated HCC (MASLD-HCC) also can develop in patients without cirrhosis. The specific pathways that trigger carcinogenesis in this context are not elucidated completely, and recommendations for HCC surveillance in MASLD patients are challenging. In the era of precision medicine, it is critical to understand the processes that define the profiles of patients at increased risk of HCC in the MASLD setting, including cardiometabolic risk factors and the molecular targets that could be tackled effectively. Ideally, defining categories that encompass key pathophysiological features, associated with tailored diagnostic and treatment strategies, should facilitate the identification of specific MASLD-HCC phenotypes. In this review, we discuss MASLD-HCC, including its epidemiology and health care burden, the mechanistic data promoting MASLD, metabolic dysfunction-associated steatohepatitis, and MASLD-HCC. Its natural history, prognosis, and treatment are addressed specifically, as the role of metabolic phenotypes of MASLD-HCC as a potential strategy for risk stratification. The challenges in identifying high-risk patients and screening strategies also are discussed, as well as the potential approaches for MASLD-HCC prevention and treatment.
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BACKGROUND AND AIMS: Immunotherapy-based regimes have changed the management of HCC. However, evidence of efficacy in patients with impaired liver function is unknown. This systematic review and meta-analysis assesses survival of HCC patients and liver dysfunction treated with immunotherapy-based regimens. METHODS: Systematic review and meta-analysis of original articles or abstracts reporting survival of HCC patients treated with immunotherapy according to liver function between 2017 and 2022. Overal survival (OS) according to restricted mean survival time (RMST) and median OS, and hazard ratio (HR) of Child-Pugh B or B/C versus Child-Pugh A were assessed while considering the line of treatment. RESULTS: Of the 2218 articles considered, 15 articles recruiting 2311 patients were included. Of these, 639 (27.7%) were Child-Pugh B and 34 (1.5%) C. RMST was 8.36 (95% CI, 6.15-10.57; I2 =93%) months, estimated from 8 studies. The HR was reported in 8 studies for survival between Child-Pugh B versus Child-Pugh A and metanalysis disclosed a 1.65 HR (95% CI,1.45-1.84; I2 =0% heterogeneity; p = 0.45). Treatment line data were available for 47% of the patients and 3 studies included patients treated with atezolizumab-bevacizumab in the first line. CONCLUSIONS: The high heterogeneity across studies reflects the incapacity of the current evidence to support the indication of immunotherapy in HCC patients with relevant liver dysfunction. It is mandatory to report complementary information to Child-Pugh classification such as prior liver decompensation, use of concomitant medication to control ascites, or signs of clinically significant portal hypertension to allow better patient stratification in future studies.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , ImunoterapiaRESUMO
BACKGROUND: Sentinel lymph node (SLN) biopsy has recently been accepted to evaluate nodal status in endometrial cancer at early stage, which is key to tailoring adjuvant treatments. Our aim was to evaluate the national implementation of SLN biopsy in terms of accuracy to detect nodal disease in a clinical setting and oncologic outcomes according to the volume of nodal disease. PATIENTS AND METHODS: A total of 29 Spanish centers participated in this retrospective, multicenter registry including patients with endometrial adenocarcinoma at preoperative early stage who had undergone SLN biopsy between 2015 and 2021. Each center collected data regarding demographic, clinical, histologic, therapeutic, and survival characteristics. RESULTS: A total of 892 patients were enrolled. After the surgery, 12.9% were suprastaged to FIGO 2009 stages III-IV and 108 patients (12.1%) had nodal involvement: 54.6% macrometastasis, 22.2% micrometastases, and 23.1% isolated tumor cells (ITC). Sensitivity of SLN biopsy was 93.7% and false negative rate was 6.2%. After a median follow up of 1.81 years, overall surivial and disease-free survival were significantly lower in patients who had macrometastases when compared with patients with negative nodes, micrometastases or ITC. CONCLUSIONS: In our nationwide cohort we obtained high sensitivity of SLN biopsy to detect nodal disease. The oncologic outcomes of patients with negative nodes and low-volume disease were similar after tailoring adjuvant treatments. In total, 22% of patients with macrometastasis and 50% of patients with micrometastasis were at low risk of nodal metastasis according to their preoperative risk factors, revealing the importance of SLN biopsy in the surgical management of patients with early stage EC.
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Neoplasias do Endométrio , Linfonodo Sentinela , Feminino , Humanos , Biópsia de Linfonodo Sentinela , Linfonodos/patologia , Micrometástase de Neoplasia/patologia , Estudos Retrospectivos , Estadiamento de Neoplasias , Neoplasias do Endométrio/cirurgia , Neoplasias do Endométrio/patologia , Linfonodo Sentinela/cirurgia , Linfonodo Sentinela/patologia , Excisão de LinfonodoRESUMO
Chemical gardens, self-assembling precipitates that spontaneously form when a metal salt is added to a solution of another precipitating anion, are of interest for various applications including producing reactive materials in controlled structures. Here, we report on two chemical garden reaction systems (CuCl2 and Cu(NO3)2 seed crystals submerged in sodium silicate) that produced self-assembled microfluidic labyrinths in a vertical 2D Hele-Shaw reactor. The formation of labyrinths as well as the specific growth modes of the precipitate were dependent on the silicate concentration: CuCl2 labyrinths formed only at 3 and 4 M silicate and Cu(NO3)2 labyrinths formed only at 4 and 5 M silicate. The labyrinth structures contained silicate on the exterior and crystalline material interpreted as hydrated minerals from the metal salt in their interiors. The bubble-guided tubes that form labyrinths can be controlled by changing the angle of the 2D reaction cell; this suggests that future experiments of this type could form self-organizing structures with controlled composition and orientation for use in microfluidics and various materials science applications.
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Pseudaminic and legionaminic acids are a subgroup of nonulosonic acids (NulOs) unique to bacterial species. There is a lack of advances in the study of these NulOs due to their complex synthesis and production. Recently, it was seen that "Candidatus Accumulibacter" can produce Pse or Leg analogues as part of its extracellular polymeric substances (EPS). In order to employ a "Ca. Accumulibacter" enrichment as production platform for bacterial sialic acids, it is necessary to determine which fractions of the EPS of "Ca. Accumulibacter" contain NulOs and how to enrich and/or isolate them. We extracted the EPS from granules enriched with "Ca. Accumulibcater" and used size-exclusion chromatography (SEC) to separate them into different molecular weight (MW) fractions. This separation resulted in two high molecular weight (> 5500 kDa) fractions dominated by polysaccharides, with a NulO content up to 4 times higher than the extracted EPS. This suggests that NulOs in "Ca. Accumulibacter" are likely located in high molecular weight polysaccharides. Additionally, it was seen that the extracted EPS and the NulO-rich fractions can bind and neutralize histones. This opens the possibility of EPS and NulO-rich fractions as potential source for sepsis treatment drugs. KEY POINTS: ⢠NulOs in "Ca. Accumulibacter" are likely located in high MW polysaccharides ⢠SEC allows to obtain high MW polysaccharide-rich fractions enriched with NulOs ⢠EPS and the NulOs-rich fractions are a potential source for sepsis treatment drugs.
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Polímeros , Polissacarídeos , Bactérias , Matriz Extracelular de Substâncias Poliméricas , EsgotosRESUMO
Polyphosphate accumulating organisms (PAOs) are responsible for enhanced biological phosphate removal (EBPR) from wastewater, where they grow embedded in a matrix of extracellular polymeric substances (EPS). EPSs comprise a mixture of biopolymers like polysaccharides or (glyco)proteins. Despite previous studies, little is known about the dynamics of EPS in mixed cultures, and their production by PAOs and potential consumption by flanking microbes. EPSs are biodegradable and have been suggested to be a substrate for other organisms in the community. Studying EPS turnover can help elucidate their biosynthesis and biodegradation cycles. We analyzed the turnover of proteins and polysaccharides in the EPS of an enrichment culture of PAOs relative to the turnover of internal proteins. An anaerobic-aerobic sequencing batch reactor (SBR) simulating EBPR conditions was operated to enrich for PAOs. After achieving a stable culture, carbon source was switched to uniformly 13C-labeled acetate. Samples were collected at the end of each aerobic phase. EPSs were extracted by alkaline treatment. 13C enrichment in proteins and sugars (after hydrolysis of polysaccharides) in the extracted EPS were measured by mass spectrometry. The average turnover rate of sugars and proteins (0.167 and 0.192 d-1 respectively) was higher than the expected value based on the solid removal rate (0.132 d-1), and no significant difference was observed between intracellular and extracellular proteins. This indicates that EPS from the PAO enriched community is not selectively degraded by flanking populations under stable EBPR process conditions. Instead, we observed general decay of biomass, which corresponds to a value of 0.048 d-1. KEY POINTS: ⢠Proteins showed a higher turnover rate than carbohydrates. ⢠Turnover of EPS was similar to the turnover of intracellular proteins. ⢠EPS is not preferentially consumed by flanking populations.
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Fósforo , Águas Residuárias , Fósforo/metabolismo , Polifosfatos/metabolismo , Matriz Extracelular/metabolismo , Polímeros , Açúcares , Reatores Biológicos , EsgotosRESUMO
One of the threats to nanometric CMOS analog circuit reliability is circuit performance degradation due to transistor aging. To extend circuit operating life, the bias of the main devices within the circuit must be adjusted while the aging degradation process affects them by using a monitor circuit that tracks the evolution of the circuit performance. In this paper, we propose the use of DC temperature measurements in the proximity of the circuit to perform the monitoring of circuit performance degradation and as an observable variable to adjust the bias of the main devices to restore the degraded performance to the original values. To this end, we present experimental results obtained from nine samples of a standard CMOS integrated circuit containing a high-frequency class-A power amplifier and a differential temperature sensor. After accelerated aging, the gain of the amplifier is degraded up to 50%. We propose two different procedures to perform DC temperature measurements that allow tracking of the amplifier gain degradation due to aging and, by uniquely observing temperature readings, automatically set a new bias for the amplifier devices that restores the original amplifier gain. Whereas one of the procedures is able to restore the gain up to a certain limit, the second allows full gain restoration.
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BACKGROUND & AIMS: Recognition of non-characterized liver nodules (NCLN) prior to direct-acting antivirals (DAAs) is associated with increased hepatocellular carcinoma (HCC) risk in patients with HCV. The risk of HCC has not been defined in F3/F4 patients in whom NCLN have been ruled-out before starting DAAs and at sustained virological response (SVR). This study aimed to estimate HCC incidence in this population. METHODS: We performed a prospective study including HCV-infected patients with F3/F4 fibrosis, without a history of HCC, and who achieved SVR after DAAs. Patients were only included if they had undergone ultrasound imaging that excluded the presence of HCC/NCLN within 30 days after SVR. All patients were evaluated every 6 months until developing primary liver cancer, death or withdrawal of informed consent. HCC incidence was expressed per 100 patient-years (/100PY). Adherence to screening program was calculated every 6 months for the first 48 months. RESULTS: A total of 185 patients (63/122, F3/F4) were included. Among those with cirrhosis, 92% were Child-Pugh A and 42.7% had clinically significant portal hypertension (CSPH). Albumin-bilirubin score was 1 in 84.9% and 2 in 15.1% of patients, respectively. The median clinical and radiologic follow-up was 52.4 months and 48 months, respectively. Ten patients developed HCC: HCC incidence was 1.46/100PY (95% CI 0.79-2.71) in the whole cohort, 2.24/100PY (95% CI 1.21-4.17) in F4 only and 3.63/100PY (95% CI 1.95-6.74) in patients with CSPH. No HCC was registered in patients with F3. Median time between SVR and HCC occurrence was 28.1 months; 12 non-primary liver cancers were also identified. CONCLUSIONS: Patients with cirrhosis without NCLN at SVR remain at risk of HCC development. The absence of HCC in patients with F3 reinforces their marginal cancer risk, but prospective studies are needed to exclude them from screening programs. LAY SUMMARY: Patients with HCV-related cirrhosis, without non-characterized liver nodules at sustained virologic response, remain at risk of hepatocellular carcinoma despite viral cure. However, the cancer risk after successful direct-acting antiviral treatment is marginal in patients with F3 fibrosis without non-characterized liver nodules. If confirmed in larger prospective studies, current screening recommendations may need to be revisited in this group of patients.
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Carcinoma Hepatocelular , Hepatite C Crônica , Hipertensão Portal , Neoplasias Hepáticas , Antivirais/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Humanos , Hipertensão Portal/complicações , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Estudos Prospectivos , Resposta Viral SustentadaRESUMO
BACKGROUND & AIMS: Information about the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in patients with liver cancer is lacking. This study characterizes the outcomes and mortality risk in this population. METHODS: Multicentre retrospective, cross-sectional, international study of liver cancer patients with SARS-CoV-2 infection registered between February and December 2020. Clinical data at SARS-CoV-2 diagnosis and outcomes were registered. RESULTS: Two hundred fifty patients from 38 centres were included, 218 with hepatocellular carcinoma (HCC) and 32 with intrahepatic cholangiocarcinoma (iCCA). The median age was 66.5 and 64.5 years, and 84.9% and 21.9% had cirrhosis in the HCC and iCCA cohorts respectively. Patients had advanced cancer stage at SARS-CoV-2 diagnosis in 39.0% of the HCC and 71.9% of the iCCA patients. After a median follow-up of 7.20 (IQR: 1.84-11.24) months, 100 (40%) patients have died, 48% of the deaths were SARS-CoV-2-related. Forty (18.4%) HCC patients died within 30-days. The death rate increase was significantly different according to the BCLC stage (6.10% [95% CI 2.24-12.74], 11.76% [95% CI 4.73-22.30], 20.69% [95% CI 11.35-31.96] and 34.52% [95% CI 17.03-52.78] for BCLC 0/A, B, C and D, respectively; p = .0017). The hazard ratio was 1.45 (95% CI 0.49-4.31; p = .5032) in BCLC-B versus 0/A, and 3.13 (95% CI 1.29-7.62; p = .0118) in BCLC-C versus 0/A in the competing risk Cox regression model. Nineteen out of 32 iCCA (59.4%) died, and 12 deaths were related to SARS-CoV-2 infection. CONCLUSIONS: This is the largest cohort of liver cancer patients infected with SARS-CoV-2. It characterizes the 30-day mortality risk of SARS-CoV-2 infected patients with HCC during this period.
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COVID-19 , Carcinoma Hepatocelular , Neoplasias Hepáticas , COVID-19/complicações , Teste para COVID-19 , Estudos de Coortes , Estudos Transversais , Humanos , Estudos Retrospectivos , SARS-CoV-2RESUMO
The initiation phase of HIV reverse transcription has features that are distinct from its elongation phase. The first structure of a reverse transcription initiation complex (RTIC) that trapped the complex after incorporation of one ddCMP nucleotide was published recently [Larsen KP, et al. (2018) Nature 557:118-122]. Here we report a crystal structure of a catalytically active HIV-1 RT/dsRNA complex that mimics the state of the RTIC before the first nucleotide incorporation. The structure reveals that the dsRNA-bound conformation of RT is closer to that of RT bound to a nonnucleoside RT inhibitor (NNRTI) and dsDNA; a hyperextended thumb conformation helps to accommodate the relatively wide dsRNA duplex. The RNA primer 3' end is positioned 5 Å away from the polymerase site; however, unlike in an NNRTI-bound state in which structural elements of RT restrict the movement of the primer, the primer terminus of dsRNA is not blocked from reaching the active site of RT. The observed structural changes and energetic cost of bringing the primer 3' end to the priming site are hypothesized to explain the slower nucleotide incorporation rate of the RTIC. An unusual crystal lattice interaction of dsRNA with its symmetry mate is reminiscent of the RNA architecture within the extended vRNA-tRNALys3 in the RTIC. This RT/dsRNA complex captures the key structural characteristics and components of the RTIC, including the RT conformational changes and interactions with the dsRNA primer-binding site region, and these features have implications for better understanding of RT initiation.
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Transcriptase Reversa do HIV/química , HIV-1/enzimologia , RNA de Cadeia Dupla/química , RNA de Transferência de Lisina/química , RNA Viral/química , Cristalografia por Raios XRESUMO
Left hepatic lobe agenesis is a rare congenital disorder, first reported by Wakefield in 1898. Since then, less than 40 cases have been described in the literature. We present the case of a man with a left hepatic lobe agenesis diagnosed during the study of obstructive jaundice.
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Fígado , Masculino , Humanos , Fígado/diagnóstico por imagemRESUMO
AIM: This study analysed the impact that COVID-19 and the response measures implemented by the Spanish Government have had on families of individuals with intellectual and developmental disabilities. METHOD: Data on 323 family members (M = 52.3 years old; SD = 10.5) were collected through an online survey, which was focused on analysing difficulties experienced and service provision during lockdown. RESULTS: Many families (66.3%) have seen their level of stress increased during lockdown because of, among other reasons, a greater burden of care. Difficulties were associated with the closure and changes in disability-related services. Families of people with extensive support needs have generally experienced greater difficulties. CONCLUSION: Support services should have been considered essential services during lockdown. The failure to receive support has resulted in excessive burden on families, who had to assume a multitude of roles to support their family member with intellectual and developmental disability.
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COVID-19 , Deficiência Intelectual , Criança , Controle de Doenças Transmissíveis , Deficiências do Desenvolvimento , Humanos , Pessoa de Meia-Idade , SARS-CoV-2RESUMO
INTRODUCTION: Enhanced recovery after bariatric surgery (ERABS) protocols consist of a combination of several preoperative, intraoperative and postoperative methods for the management of the surgical patient. The aim of this study was to evaluate the impact of the ERABS protocol on length of hospital stay (LOS) and postoperative complications. MATERIAL AND METHODS: Retrospective study of patients who underwent elective Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) between 2015 and 2018. From 2015 to 2017, patients received traditional management (pre-ERABS group). Those who underwent surgery during 2018 were managed with our ERABS protocol (ERABS group). The primary outcome was LOS. Secondary outcomes were readmission rate and 30-day postoperative complications. RESULTS: A total of 200 patients who received RYGB and SG between 2015 and 2018 were retrospectively analyzed; we included 120 patients in the pre-ERABS group and 80 in the ERABS group. The median LOS was four days [2-49] in the pre-ERABS group, as compared with two days [1-26] in the ERABS group (p < .0001). No significant differences were found in postoperative complication rates, readmissions, and mortality. CONCLUSION: Implementation of the ERABS protocol is related to a better postoperative recovery and allows an early discharge without increasing postoperative complications, readmissions or mortality.
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Cirurgia Bariátrica , Recuperação Pós-Cirúrgica Melhorada , Derivação Gástrica , Laparoscopia , Obesidade Mórbida , Gastrectomia , Humanos , Tempo de Internação , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
MOTIVATION: Detailed patient data are crucial for medical research. Yet, these healthcare data can only be released for secondary use if they have undergone anonymization. RESULTS: We present and describe µ-ANT, a practical and easily configurable anonymization tool for (healthcare) data. It implements several state-of-the-art methods to offer robust privacy guarantees and preserve the utility of the anonymized data as much as possible. µ-ANT also supports the heterogenous attribute types commonly found in electronic healthcare records and targets both practitioners and software developers interested in data anonymization. AVAILABILITY AND IMPLEMENTATION: (source code, documentation, executable, sample datasets and use case examples) https://github.com/CrisesUrv/microaggregation-based_anonymization_tool.
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Pesquisa Biomédica , Anonimização de Dados , Humanos , Privacidade , Semântica , SoftwareRESUMO
The presence of plastic in the environment is generating impacts on all habitats and has become a major global problem in marine megafauna. Macroplastics can cause entanglement, ingestion and loss of suitable habitats. In addition to entanglement problems, there is evidence that plastics are entering the food web through ingestion by marine organisms, which could ultimately be affecting humans. Much of the available information on the impact of plastic in biota is scattered and disconnected due to the use of different methodologies. Here, we review the variety of approaches and protocols followed to assess macro- and microplastic ingestion in marine vertebrates such as sea turtles, cetaceans and fishes in order to offer a global overview of their current status. The analysis of 112 studies indicates the highest plastic ingestion in organisms collected in the Mediterranean and Northeast Indian Ocean with significant differences among plastic types ingested by different groups of animals, including differences in colour and the type of prevalent polymers. In sea turtles, the most prevalent types of plastics are white plastics (66.60%), fibres (54.54%) and LDPE polymer (39.09%); in cetaceans, white macro- and microplastics (38.31%), fibres (79.95%) and PA polymer (49.60%); and in fishes, transparent plastics (45.97%), fibres (66.71%) and polyester polymer (36.20%). Overall, clear fibre microplastics are likely the most predominant types ingested by marine megafauna around the globe.
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Tartarugas , Poluentes Químicos da Água , Animais , Organismos Aquáticos , Ingestão de Alimentos , Monitoramento Ambiental , Cadeia Alimentar , Oceano Índico , Plásticos , Poluentes Químicos da Água/análiseRESUMO
Nonulosonic acids (NulOs) are a family of acidic carbohydrates with a nine-carbon backbone, which include different related structures, such as sialic acids. They have mainly been studied for their relevance in animal cells and pathogenic bacteria. Recently, sialic acids have been discovered as an important compound in the extracellular matrix of virtually all microbial life and in "Candidatus Accumulibacter phosphatis", a well-studied polyphosphate-accumulating organism, in particular. Here, bioaggregates highly enriched with these bacteria (approx. 95% based on proteomic data) were used to study the production of NulOs in an enrichment of this microorganism. Fluorescence lectin-binding analysis, enzymatic quantification, and mass spectrometry were used to analyze the different NulOs present, showing a wide distribution and variety of these carbohydrates, such as sialic acids and bacterial NulOs, in the bioaggregates. Phylogenetic analysis confirmed the potential of "Ca. Accumulibacter" to produce different types of NulOs. Proteomic analysis showed the ability of "Ca. Accumulibacter" to reutilize and reincorporate these carbohydrates. This investigation points out the importance of diverse NulOs in non-pathogenic bacteria, which are normally overlooked. Sialic acids and other NulOs should be further investigated for their role in the ecology of "Ca. Accumulibacter" in particular, and biofilms in general. KEY POINTS: â¢"Ca. Accumulibacter" has the potential to produce a range of nonulosonic acids. â¢Mass spectrometry and lectin binding can reveal the presence and location of nonulosonic acids. â¢The role of nonulosonic acid in non-pathogenic bacteria needs to be studied in detail.
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Reatores Biológicos , Matriz Extracelular de Substâncias Poliméricas , Fósforo , Filogenia , Proteômica , EsgotosRESUMO
OBJECTIVE: To report a case of successful use of golimumab (GLB) in a patient with ulcerative colitis (UC) refractory to infliximab (IFX) and adalimumab (ADA). CASE SUMMARY: A 60-year-old man was diagnosed with left UC and was given azathioprine 2.5 mg/kg to control UC symptoms and decrease corticosteroid patient dependence. Four years later, he developed adverse reaction to azathioprine and began treatment with mercaptopurine 1.5 mg/kg/day. Despite this treatment, he developed a severe relapse (Truelove-Witts modified: 15 points). Treatment with IFX 5 mg/kg at weeks 0, 2, 6, and every 8 weeks was started. After 1 year in clinical remission, the patient developed an infusion reaction to IFX, and IFX was suspended. The patient started treatment with ADA 40 mg every other week. After 2 years in clinical remission, ADA was suspended. 20 months after ADA discontinuation, the patient developed an acute episode of UC with a Truelove-Witts modified score of 16 points. ADA plus corticosteroid therapy was restarted. Despite these treatments, the patient's clinical condition did not improved. ADA 40 mg per week was started with not clinical improvement and with corticosteroid dependence after 4 months of ADA intensive therapy. The patient denied surgery, and cyclosporine was discarded because of its inability to be used as a maintenance drug. The patient started GLB with an induction dosage regimen of 200 mg subcutaneous at week 0, followed by 100 mg at week 2, and then maintenance therapy with 100 mg every 4 weeks (patient's weight = 84 kg), combined with mercaptopurine and corticosteroids. After 6 weeks of treatment, the patient achieved clinical remission, with just three non-bleeding stools per day, without stomach ache, apyretic, and no urgency or tenesmus rectal symptoms. One year later, the patient continued to be asymptomatic with a Truelove-Witts modified score of 2 points, corticoid-free treatment, and a complete clinical and endoscopic remission and normal calprotectin levels (< 15 µg/g). We decided to suspend mercaptopurine in order to avoid side effects derived from the combined treatment. After 1 year on GLB therapy, the patient continued in clinical remission. CONCLUSIONS: Based on our case, GLB could be selected as an effective approach for patients with UC refractory to IFX and ADA. However, further studies need to be performed to evaluate the efficacy of GLB therapy as a rescue treatment.
Assuntos
Colite Ulcerativa , Adalimumab/uso terapêutico , Anticorpos Monoclonais/efeitos adversos , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/tratamento farmacológico , Humanos , Infliximab , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
PURPOSE: Screening for obstructive sleep apnea (OSA) is recommended in patients scheduled for bariatric surgery because continuous positive airway pressure (CPAP) therapy in patients with moderate-to-severe OSA reduces postoperative complications. However, cardiorespiratory polygraphy (CRP) and polysomnography (PSG) are expensive and time-consuming. The present study aimed to assess whether at-home continuous overnight pulse oximetry can be used to diagnose moderate-to-severe OSA in patients scheduled for bariatric surgery. METHODS: In this prospective observational study, we enrolled consecutive patients scheduled for bariatric surgery. Patients with no prior OSA diagnosis were evaluated using the ESS, SBQ, and preoperative at-home CRP. Correlations were calculated between AHI and oximetry parameters. For each oximetry parameter, a receiver-operating characteristic (ROC) curve was generated to identify optimal cut-off values for diagnosing moderate-to-severe OSA. RESULTS: In total, 117 patients were included. The oxygen desaturation index was the most correlated oximetry parameter; the optimal cut-off value for diagnosing moderate-to-severe OSA was 23.9. The sensitivity and specificity were 80 and 92%, respectively. The area under the ROC curve was 0.935. CONCLUSIONS: At-home continuous overnight pulse oximetry could be used to screen moderate-to-severe OSA in patients scheduled for bariatric surgery because it would allow clinicians to implement early CPAP therapy and avoid preoperative PSG or CRP.