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Tuberculosis (TB), the leading cause of death from bacterial infections worldwide, results from infection with Mycobacterium tuberculosis (Mtb). The antitubercular agents delamanid (DLM) and pretomanid (PMD) are nitroimidazole prodrugs that require activation by an enzyme intrinsic to Mtb; however, the mechanism(s) of action and the associated metabolic pathways are largely unclear. Profiling of the chemical-genetic interactions of PMD and DLM in Mtb using combined CRISPR screening reveals that the mutation of rv2073c increases susceptibility of Mtb to these nitroimidazole drugs both in vitro and in infected mice, whereas mutation of rv0078 increases drug resistance. Further assays show that Rv2073c might confer intrinsic resistance to DLM/PMD by interfering with inhibition of the drug target, decaprenylphophoryl-2-keto-b-D-erythro-pentose reductase (DprE2), by active nicotinamide adenine dinucleotide (NAD) adducts. Characterization of the metabolic pathways of DLM/PMD in Mtb using a combination of chemical genetics and comparative liquid chromatography-mass spectrometry (LC-MS) analysis of DLM/PMD metabolites reveals that Rv0077c, which is negatively regulated by Rv0078, mediates drug resistance by metabolizing activated DLM/PMD. These results might guide development of new nitroimidazole prodrugs and new regimens for TB treatment.
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BACKGROUND: Although conservative treatment is typically recommended for pregnant patients with pituitary adenoma (PA), surgical treatment is occasionally necessary for those with acute symptoms. Currently, surgical interventions utilized among these patients is poorly studied. AIM: To evaluate the surgical indications, timing, perioperative precautions and postoperative complications of PAs during pregnancy and to provide comprehensive guidance. METHODS: Six patients with PAs who underwent surgical treatment during pregnancy at Peking Union Medical College Hospital between January 1990 and June 2021 were recruited for this study. Another 35 pregnant patients who were profiled in the literature were included in our analysis. RESULTS: The 41 enrolled patients had acute symptoms including visual field defects, severe headaches or vision loss that required emergency pituitary surgeries. PA apoplexies were found in 23 patients. The majority of patients (55.9%) underwent surgery in the second trimester of pregnancy. A multidisciplinary team was involved in patient care from the preoperative period through the postpartum period. With the exception of 1 patient who underwent an induced abortion and 1 fetus that died due to a nuchal cord, 39 patients delivered successfully. Among them, 37 fetuses were healthy until the most recent follow-up. CONCLUSION: PA surgery during pregnancy is effective and safe during the second and third trimesters. Pregnant patients requiring emergency PA surgery require multidisciplinary evaluation and healthcare management.
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Multiple genetic changes in the enteric pathogen Yersinia pseudotuberculosis have driven the emergence of Yesinia pestis, the arthropod-borne, etiological agent of plague. These include developing the capacity for biofilm-dependent blockage of the flea foregut to enable transmission by flea bite. Previously, we showed that pseudogenization of rcsA, encoding a component of the Rcs signalling pathway, is an important evolutionary step facilitating Y. pestis flea-borne transmission. Additionally, rcsD, another important gene in the Rcs system, harbours a frameshift mutation. Here, we demonstrated that this rcsD mutation resulted in production of a small protein composing the C-terminal RcsD histidine-phosphotransferase domain (designated RcsD-Hpt) and full-length RcsD. Genetic analysis revealed that the rcsD frameshift mutation followed the emergence of rcsA pseudogenization. It further altered the canonical Rcs phosphorylation signal cascade, fine-tuning biofilm production to be conducive with retention of the pgm locus in modern lineages of Y. pestis. Taken together, our findings suggest that a frameshift mutation in rcsD is an important evolutionary step that fine-tuned biofilm production to ensure perpetuation of flea-mammal plague transmission cycles.
Yersinia pestis, the agent responsible for the plague, emerged 6,000 to 7,000 years ago from Yersinia pseudotuberculosis, another type of bacteria which still exists today. Although they are highly similar genetically, these two species are strikingly different. While Y. pseudotuberculosis spreads via food and water and causes mild stomach distress, Y. pestis uses fleas to infect new hosts and has killed millions. A small set of genetic changes has contributed to the emergence of Y. pestis by allowing it to thrive inside a flea and maximise its transmission. In particular, some of these mutations have led to the bacteria being able to come together to form a sticky layer that adheres to the gut of the insect, with this 'biofilm' stopping the flea from feeding on blood. The starving flea keeps trying to feed, and with each bite comes another opportunity for Y. pestis to jump host. However, it remains unclear exactly how the mutations have influenced biofilm formation to allow for this new transmission mechanism to take place. To examine this phenomenon, Guo et al. focused on rcsD, a gene that codes for a component of the signalling system that controls biofilm creation. In Y. pestis this sequence has been mutated to become a 'pseudogene', a type of sequence which is often thought to be non-functional. However, the experiments showed that, in Y. pestis, rcsD could produce small amounts of a full-length RcsD protein similar to the one found in Y. pseudotuberculosis. However, the gene mostly produces a short 'RcsD-Hpt' protein that can, in turn, alter the expression of many genes, including those that decrease biofilm formation. This may prove to be beneficial for Y. pestis, for example when the bacteria switches from living in fleas to living in humans, where it does not require a biofilm. Guo et al. further investigated the impact of rcsD becoming a pseudogene inY. pestis, showing that if normal amounts of the full-length RcsD protein are produced, the bacteria quickly lose the gene that allows them to form biofilm in fleas, and cause disease in humans. In fact, additional analyses revealed that all sequenced strains of ancient and modern Y. pestis bacteria can produce RcsD-Hpt, even if they do not carry the same exact rcsD mutation. Overall, these results indicate that rcsD turning into a pseudogene marked an important step in the emergence of Y. pestis strains that can cause lasting plague outbreaks. They also point towards pseudogenes having more important roles in evolution than previously thought.
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Peste , Siphonaptera , Yersinia pestis , Animales , Peste/genética , Yersinia pestis/genética , Yersinia pestis/metabolismo , Mutación del Sistema de Lectura , MamíferosRESUMEN
CRISPR screening, including CRISPR interference (CRISPRi) and CRISPR-knockout (CRISPR-KO) screening, has become a powerful technology in the genetic screening of eukaryotes. In contrast with eukaryotes, CRISPR-KO screening has not yet been applied to functional genomics studies in bacteria. Here, we constructed genome-scale CRISPR-KO and also CRISPRi libraries in Mycobacterium tuberculosis (Mtb). We first examined these libraries to identify genes essential for Mtb viability. Subsequent screening identified dozens of genes associated with resistance/susceptibility to the antitubercular drug bedaquiline (BDQ). Genetic and chemical validation of the screening results suggested that it provided a valuable resource to investigate mechanisms of action underlying the effects of BDQ and to identify chemical-genetic synergies that can be used to optimize tuberculosis therapy. In summary, our results demonstrate the potential for efficient genome-wide CRISPR-KO screening in bacteria and establish a combined CRISPR screening approach for high-throughput investigation of genetic and chemical-genetic interactions in Mtb.
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Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Mycobacterium tuberculosis , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Mycobacterium tuberculosis/genética , Sistemas CRISPR-Cas , Genómica/métodos , GenomaRESUMEN
Clostridium tyrobutyricum (C. tyrobutyricum) is a fermentation strain used to produce butyric acid. A promising new biofuel, n-butanol, can be produced by catalysis of butyrate, which can be obtained through microbial fermentation. Butyric acid has various uses in food additives and flavor agents, antiseptic substances, drug formulations, and fragrances. Its use as a food flavoring has been approved by the European Union, and it has therefore been listed on the EU Lists of Flavorings. As butyric acid fermentation is a cost-efficient process, butyric acid is an attractive feedstock for various biofuels and food commercialization products. 12C6+ irradiation has advantages over conventional mutation methods for fermentation production due to its dosage conformity and excellent biological availability. Nevertheless, the effects of these heavy-ion irradiations on the specific productiveness of C. tyrobutyricum are still uncertain. We developed non-structured mathematical models to represent the heavy-ion irradiation of C. tyrobutyricum in biofermentation reactors. The kinetic models reflect various fermentation features of the mutants, including the mutant strain growth model, butyric acid formation model, and medium consumption model. The models were constructed based on the Markov chain Monte Carlo model and logistic regression. Models were verified using experimental data in response to different initial glucose concentrations (0-180 g/L). The parameters of fixed proposals are applied in the various fermentation stages. Predictions of these models were in accordance well with the results of fermentation assays. The maximum butyric acid production was 56.3 g/L. Our study provides reliable information for increasing butyric acid production and for evaluating the feasibility of using mutant strains of C. tyrobutyricum at the pre-development phase.
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Butanol inhibits bacterial activity by destroying the cell membrane of Clostridium acetobutylicum strains and altering functionality. Butanol toxicity also results in destruction of the phosphoenolpyruvate-carbohydrate phosphotransferase system (PTS), thereby preventing glucose transport and phosphorylation and inhibiting transmembrane transport and assimilation of sugars, amino acids, and other nutrients. In this study, based on the addition of exogenous butanol, the tangible macro indicators of changes in the carbon ion beam irradiation-mutant Y217 morphology were observed using scanning electron microscopy (SEM). The mutant has lower microbial adhesion to hydrocarbon (MATH) value than C. acetobutylicum ATCC 824 strain. FDA fluorescence intensity and conductivity studies demonstrated the intrinsically low membrane permeability of the mutant membrane, with membrane potential remaining relatively stable. Monounsaturated FAs (MUFAs) accounted for 35.17% of the mutant membrane, and the saturated fatty acids (SFA)/unsaturated fatty acids (UFA) ratio in the mutant cell membrane was 1.65. In addition, we conducted DNA-level analysis of the mutant strain Y217. Expectedly, through screening, we found gene mutant sites encoding membrane-related functions in the mutant, including ATP-binding cassette (ABC) transporter-related genes, predicted membrane proteins, and the PTS transport system. It is noteworthy that an unreported predicted membrane protein (CAC 3309) may be related to changes in mutant cell membrane properties. KEY POINTS: ⢠Mutant Y217 exhibited better membrane integrity and permeability. ⢠Mutant Y217 was more resistant to butanol toxicity. ⢠Some membrane-related genes of mutant Y217 were mutated.
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Butanoles , Clostridium acetobutylicum , 1-Butanol , Butanoles/toxicidad , Proteínas de la MembranaRESUMEN
New tools for genetic manipulation of Mycobacterium tuberculosis are needed for the development of new drug regimens and vaccines aimed at curing tuberculosis infections. Clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated protein (Cas) systems generate a highly specific double-strand break at the target site that can be repaired via nonhomologous end joining (NHEJ), resulting in the desired genome alteration. In this study, we first improved the NHEJ repair pathway and developed a CRISPR-Cas-mediated genome-editing method that allowed us to generate markerless deletion in Mycobacterium smegmatis, Mycobacterium marinum, and M. tuberculosis Then, we demonstrated that this system could efficiently achieve simultaneous generation of double mutations and large-scale genetic mutations in M. tuberculosis Finally, we showed that the strategy we developed can also be used to facilitate genome editing in Escherichia coliIMPORTANCE The global health impact of M. tuberculosis necessitates the development of new genetic tools for its manipulation, to facilitate the identification and characterization of novel drug targets and vaccine candidates. Clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated protein (Cas) genome editing has proven to be a powerful genetic tool in various organisms; to date, however, attempts to use this approach in M. tuberculosis have failed. Here, we describe a genome-editing tool based on CRISPR cleavage and the nonhomologous end-joining (NHEJ) repair pathway that can efficiently generate deletion mutants in M. tuberculosis More importantly, this system can generate simultaneous double mutations and large-scale genetic mutations in this species. We anticipate that this CRISPR-NHEJ-assisted genome-editing system will be broadly useful for research on mycobacteria, vaccine development, and drug target profiling.
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Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Reparación del ADN por Unión de Extremidades , Edición Génica , Genoma Bacteriano , Mycobacterium tuberculosis/genética , Toxinas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Sistemas CRISPR-Cas , Modelos Biológicos , Mycobacterium smegmatis/genética , Mycobacterium tuberculosis/metabolismo , Unión Proteica , ARN Guía de Kinetoplastida , Rec A Recombinasas/metabolismoRESUMEN
BACKGROUND: Intervertebral disc degeneration (IDD) is a major contributor to back, neck, and radicular pain, and the treatment of IDD is costly and relatively ineffective. Dysregulation of microRNAs (miRNAs) has been reported to be involved in IDD. The purpose of our study is to illustrate the potential that miR-143-5p targeting eEF2 gene mediates IDD. METHODS: Following the establishment of the IDD rat models, expression of miR-143-5p, eEF2, Bcl-2, Bax, AMPK, mTOR, cyclinD, COL2, ACAN, and DCN was detected. The NP cells isolated from degenerative intervertebral disc (IVD) were introduced with a series of mimic, inhibitor, or AICAR to explore the functional role of miR-143-5p in IDD and to characterize the relationship between miR-143-5p and eEF2. Cell viability, cell cycle, apoptosis, and senescence were also evaluated. RESULTS: A reduction in eEF2, an increase in miR-143-5p, and activation of the AMPK signaling pathway were observed in degenerative IVD. Moreover, increased senescent NP cells were observed in degenerative IVD. eEF2 was confirmed as a target gene of miR-143-5p. miR-143-5p was found to activate the AMPK signaling pathway. The restoration of miR-143-5p or the activation of AMPK signaling pathway decreased COL2, ACAN, and DCN expression, coupled with the inhibition of NP cell proliferation and differentiation, and promotion of NP apoptosis and senescence. On the contrary, the inhibition of miR-143-5p led to the reversed results. CONCLUSION: The results demonstrated that the inhibition of miR-143-5p may act as a suppressor for the progression of IDD.
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Proteínas Quinasas Activadas por AMP/metabolismo , Quinasa del Factor 2 de Elongación/biosíntesis , Degeneración del Disco Intervertebral/metabolismo , MicroARNs/biosíntesis , Transducción de Señal/fisiología , Proteínas Quinasas Activadas por AMP/genética , Animales , Células Cultivadas , Quinasa del Factor 2 de Elongación/antagonistas & inhibidores , Quinasa del Factor 2 de Elongación/genética , Degeneración del Disco Intervertebral/genética , Masculino , MicroARNs/genética , Ratas , Ratas Endogámicas LewRESUMEN
ABSTRACT Objectives: Our study aimed to investigate the associations of glucose tolerance status with insulin-like growth factor-I (IGF-I) and other clinical laboratory parameters of acromegalic patients before and after the patients underwent transsphenoidal adenomectomy (TSA) by conducting a single-center, retrospective study. Subjects and methods: A total of 218 patients with acromegaly who had undergone TSA as the first treatment were retrospectively analyzed. Serum IGF-I, growth hormone (GH) and glucose levels were measured before and after surgery. Results: The follow-up levels for random GH, GH nadir, and the percentage of the upper limit of normal IGF-I (%ULN IGF-I) were decreased significantly. The percentages of normal (39.0%), early carbohydrate metabolism disorders (33.0%) and diabetes mellitus (28.0%) changed to 70.2%, 16.5% and 13.3%, respectively, after TSA. %ULN IGF-I at baseline was higher in the diabetes mellitus (DM) group than in the normal glucose tolerance group and impaired glucose tolerance (IGT) /impaired fasting glucose (IFG) groups before TSA, and the DM group exhibited a greater reduction in %ULN IGF-I value after surgery. The follow-up %ULN IGF-I value after surgery was significantly lower in the improved group, and Pearson's correlation analysis revealed that the reductions in %ULN IGF-I corresponded with the reductions in glucose level. Conclusion: This study examined the largest reported sample with complete preoperative and follow-up data. The results suggest that the age- and sex-adjusted IGF-I level, which reflects altered glucose metabolism, and the change of it are associated with improved glucose tolerance in acromegalic patients both before and after TSA.
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Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Acromegalia/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Adenoma/cirugía , Intolerancia a la Glucosa/sangre , Adenoma Hipofisario Secretor de Hormona del Crecimiento/cirugía , Periodo Posoperatorio , Glucemia/análisis , Adenoma/sangre , Estudios Retrospectivos , Estudios de Seguimiento , Resultado del Tratamiento , Hormona de Crecimiento Humana/sangre , Diabetes Mellitus/sangre , Adenoma Hipofisario Secretor de Hormona del Crecimiento/sangre , Periodo PreoperatorioRESUMEN
OBJECTIVES: Our study aimed to investigate the associations of glucose tolerance status with insulin-like growth factor-I (IGF-I) and other clinical laboratory parameters of acromegalic patients before and after the patients underwent transsphenoidal adenomectomy (TSA) by conducting a single-center, retrospective study. SUBJECTS AND METHODS: A total of 218 patients with acromegaly who had undergone TSA as the first treatment were retrospectively analyzed. Serum IGF-I, growth hormone (GH) and glucose levels were measured before and after surgery. RESULTS: The follow-up levels for random GH, GH nadir, and the percentage of the upper limit of normal IGF-I (%ULN IGF-I) were decreased significantly. The percentages of normal (39.0%), early carbohydrate metabolism disorders (33.0%) and diabetes mellitus (28.0%) changed to 70.2%, 16.5% and 13.3%, respectively, after TSA. %ULN IGF-I at baseline was higher in the diabetes mellitus (DM) group than in the normal glucose tolerance group and impaired glucose tolerance (IGT) /impaired fasting glucose (IFG) groups before TSA, and the DM group exhibited a greater reduction in %ULN IGF-I value after surgery. The follow-up %ULN IGF-I value after surgery was significantly lower in the improved group, and Pearson's correlation analysis revealed that the reductions in %ULN IGF-I corresponded with the reductions in glucose level. CONCLUSION: This study examined the largest reported sample with complete preoperative and follow-up data. The results suggest that the age- and sex-adjusted IGF-I level, which reflects altered glucose metabolism, and the change of it are associated with improved glucose tolerance in acromegalic patients both before and after TSA.
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Acromegalia/sangre , Adenoma/cirugía , Intolerancia a la Glucosa/sangre , Adenoma Hipofisario Secretor de Hormona del Crecimiento/cirugía , Factor I del Crecimiento Similar a la Insulina/análisis , Adenoma/sangre , Adulto , Glucemia/análisis , Diabetes Mellitus/sangre , Femenino , Estudios de Seguimiento , Adenoma Hipofisario Secretor de Hormona del Crecimiento/sangre , Hormona de Crecimiento Humana/sangre , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Periodo Preoperatorio , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
We previously reported that among the 37 RING finger protein (RNF) family members, RNF183 mRNA is specifically expressed in the kidney under normal conditions. However, the mechanism supporting its kidney-specific expression pattern remains unclear. In this study, we elucidated the mechanism of the transcriptional activation of murine Rnf183 in inner-medullary collecting duct cells. Experiments with anti-RNF183 antibody revealed that RNF183 is predominantly expressed in the renal medulla. Among the 37 RNF family members, Rnf183 mRNA expression was specifically increased in hypertonic conditions, a hallmark of the renal medulla. RNF183 up-regulation was consistent with the activation of nuclear factor of activated T cells 5 (NFAT5), a transcription factor essential for adaptation to hypertonic conditions. Accordingly, siRNA-mediated knockdown of NFAT5 down-regulated RNF183 expression. Furthermore, the -3,466 to -3,136-bp region upstream of the mouse Rnf183 promoter containing the NFAT5-binding motif is conserved among mammals. A luciferase-based reporter vector containing the NFAT5-binding site was activated in response to hypertonic stress, but was inhibited by a mutation at the NFAT5-binding site. ChIP assays revealed that the binding of NFAT5 to this DNA site is enhanced by hypertonic stress. Of note, siRNA-mediated RNF183 knockdown increased hypertonicity-induced caspase-3 activation and decreased viability of mIMCD-3 cells. These results indicate that (i) RNF183 is predominantly expressed in the normal renal medulla, (ii) NFAT5 stimulates transcriptional activation of Rnf183 by binding to its cognate binding motif in the Rnf183 promoter, and (iii) RNF183 protects renal medullary cells from hypertonicity-induced apoptosis.
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Regulación Enzimológica de la Expresión Génica , Túbulos Renales Colectores/metabolismo , Presión Osmótica , Factores de Transcripción/metabolismo , Ubiquitina-Proteína Ligasas/biosíntesis , Regulación hacia Arriba , Animales , Caspasa 3/genética , Caspasa 3/metabolismo , Células HEK293 , Células HeLa , Humanos , Túbulos Renales Colectores/citología , Ratones , Elementos de Respuesta , Factores de Transcripción/genética , Transcripción Genética , Ubiquitina-Proteína Ligasas/genéticaRESUMEN
Objective To explore the influence of the iodine disinfection on nasal bacterial colonization through the transsphenoidal approach. Methods Totally 133 pituitary adenoma patients who underwent transsphenoidal surgery in our department from January to August 2017 were enrolled in this study. Before disinfection,pharyngeal swabs of inferior turbinate root secretions were taken for bacterial culture. After iodine disinfection,pharyngeal swabs were taken again at the same site. Changes in the nasal bacterial spectrum before and after disinfection were compared. Patients were followed up for three months after the surgery,during which any intracranial infection/bacteraemia was recorded,and its correlation with nasal bacteria colonization was analyzed. Results Nasal bacterial colonization was detected in 45 (33.8%) of 133 patients before iodine disinfection and in only 6 cases (4.5%) after iodine disinfection (χ2=34.5,P=0.000). Thus,iodine disinfection eliminated 86.7%(39/45) of the colonized bacteria. The most common nasal bacterium was Staphylococcus aureus (24.4%,11/45),followed by Klebsiella pneumoniae (24.4%,11/45),and Staphylococcus epidermidis (13.3%,6/45). One patient had high fever and chills 2 days after surgery,but blood culture and cerebrospinal fluid culture showed negative Results . After the administration of third-generation cephalosporins,the symptoms disappeared after two days. Conclusion sThere are colonized bacteria in nasal cavity. Iodine disinfection of nasal cavity can effectively clear most of the nasal bacteria. The possibility of intracranial infection/bacteremia after transsphenoidal approach is low.
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Bacterias/aislamiento & purificación , Desinfección , Cavidad Nasal/microbiología , Adenoma/cirugía , Humanos , Neoplasias Hipofisarias/cirugíaRESUMEN
We identified 37 ubiquitin ligases containing RING-finger and transmembrane domains. Of these, we found that RNF183 is abundantly expressed in the kidney. RNF183 predominantly localizes to the endoplasmic reticulum (ER), Golgi, and lysosome. We identified Sec16A, which is involved in coat protein complex II vesicle formation, as an RNF183-interacting protein. RNF183 colocalized with Sec16A and interacted through the central conserved domain (CCD) of Sec16A. Although Sec16A is not a substrate for RNF183, RNF183 was more rapidly degraded by the ER-associated degradation (ERAD) in the absence of Sec16A. Sec16A also stabilized the interacting ubiquitin ligase RNF152, which localizes to the lysosome and has structural similarity with RNF183. These results suggest that Sec16A appears to regulate the protein stability and localization of lysosomal ubiquitin ligases.
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Vesículas Cubiertas por Proteínas de Revestimiento/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas de Transporte Vesicular/fisiología , Retículo Endoplásmico/metabolismo , Aparato de Golgi/metabolismo , Humanos , Lisosomas/metabolismoRESUMEN
3' untranslated regions (3' UTRs) and particularly long 3' UTRs have been shown to act as a new class of post-transcriptional regulatory element. We previously reported that hmsT mRNA stability is negatively regulated by the 3' UTR of hmsT in Yersinia pestis. To investigate more general effects of 3' UTRs in Y. pestis, we selected 15 genes potentially possessing long 3' UTRs with different AU content and constructed their 3' UTR deletion mutants. Deletion of AU-rich 3' UTRs increased mRNA levels, whereas deletion of 3' UTRs with normal AU content resulted in slight or no changes in the mRNA level. In addition, we found that PNPase was important for 3' UTR-mediated mRNA decay when the transcriptional terminator was Rho-dependent. Finally, we showed that ribosomes promote mRNA stability when bound to a 3' UTR. Our findings suggest that functional 3' UTRs might be broadly distributed in bacteria and their novel regulatory mechanisms require further investigation.
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Calcaneal fractures, often caused by a fall from a height, are the most common injuries encountered by orthopedic surgeons. Currently, open anatomic reduction and internal fixation (ORIF) is considered a valuable treatment of displaced intraarticular fractures of the calcaneus; however, the need for bone grafting in the treatment is still controversial. Therefore, in the present study, we investigated the outcomes of 2 methods (with and without bone grafting) used for the surgical treatment of Sanders type III calcaneal fractures. From January 2013 to September 2015, 57 cases (55 patients) with displaced Sanders type III calcaneal fractures (53 unilateral and 2 bilateral) were enrolled. The patients were divided into 2 groups: group I was treated by ORIF with bone grafting (n = 28) and group II was treated by ORIF without bone grafting (n = 29). The radiologic evaluation included Böhler's angle, Gissane's angle, and the height and width of the calcaneum. In addition, the American Orthopaedic Foot and Ankle Society questionnaires and visual analog scale were completed by the patients. During the follow-up period, no differences were found in the outcome measures (Böhler's angle, p = .447; Gissane's angle, p = .599; calcaneal height, p = .065; calcaneal width p = .077; and American Orthopaedic Foot and Ankle Society questionnaires, p = .282) with or without bone grafting. The only difference between the 2 groups was the occurrence of postoperative pain (p = .024 and p = ≤ .05), which was greater in the patients who had undergone bone grafting. We have provided evidence that bone grafting with internal fixation in the treatment of intraarticular calcaneal fractures failed to improve the restoration of Böhler's angle or Gissane's angle. No statistically significant difference was found in the short-term outcomes between the 2 methods used for the surgical treatment of Sanders type III calcaneal fractures.
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Trasplante Óseo/métodos , Calcáneo/cirugía , Fijación Interna de Fracturas/métodos , Fracturas Óseas/cirugía , Imagenología Tridimensional , Fracturas Intraarticulares/cirugía , Adulto , Fracturas de Tobillo/diagnóstico por imagen , Fracturas de Tobillo/cirugía , Placas Óseas , Tornillos Óseos , Calcáneo/diagnóstico por imagen , Calcáneo/lesiones , Estudios de Cohortes , Femenino , Fijación Interna de Fracturas/instrumentación , Curación de Fractura/fisiología , Fracturas Óseas/diagnóstico por imagen , Humanos , Fracturas Intraarticulares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Medición de Riesgo , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento , Adulto JovenRESUMEN
The Rcs phosphorelay system, a non-orthodox two-component regulatory system, integrates environmental signals, regulates gene expression, and alters the physiological behavior of members of the Enterobacteriaceae family of Gram-negative bacteria. Recent studies of Rcs system focused on protein interactions, functions, and the evolution of Rcs system components and its auxiliary regulatory proteins. Herein we review the latest advances on the Rcs system proteins, and discuss the roles that the Rcs system plays in the environmental adaptation of various Enterobacteriaceae species.
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Yersinia pestis biofilm formation, controlled by intracellular levels of the second messenger molecule cyclic diguanylate (c-di-GMP), is important for blockage-dependent plague transmission from fleas to mammals. HmsCDE is a tripartite signaling system that modulates intracellular c-di-GMP levels to regulate biofilm formation in Y. pestis. Previously, we found that Y. pestis biofilm formation is stimulated in reducing environments in an hmsCDE-dependent manner. However, the mechanism by which HmsCDE senses the redox state remains elusive. Using a dsbA mutant and the addition of Cu2+ to simulate reducing and oxidizing periplasmic environments, we found that HmsC protein levels are decreased and the HmsC-HmsD protein-protein interaction is weakened in a reducing environment. In addition, we revealed that intraprotein disulphide bonds are critical for HmsC since breakage lowers protein stability and diminishes the interaction with HmsD. Our results suggest that HmsC might play a major role in sensing the environmental changes.
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Proteínas Bacterianas/fisiología , Biopelículas/crecimiento & desarrollo , Proteínas Periplasmáticas/fisiología , Peste/microbiología , Yersinia pestis/fisiología , Proteínas Bacterianas/genética , Sulfato de Cobre/metabolismo , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Oxidación-Reducción , Proteínas Periplasmáticas/genética , Estabilidad ProteicaRESUMEN
Endometriosis, which affects up to 10% of women of reproductive age, is defined as endometrial-like gland and stroma tissue growths outside the uterine cavity. Despite increasing research efforts, there are no current effective treatment methods for this disease, therefore investigations for therapeutic strategies are of primary concern. In preliminary work, the authors demonstrated that curcumin inhibits endometriosis in vivo. The present in vitro study aimed to investigate the association between endometriotic stromal cells and curcumin and to clarify the underlying mechanism of action. A total of 14 patients with endometriosis were enrolled in the present study. The purity of endometrial stromal cell cultures was proven by standard immunofluorescent staining of vimentin. The cell proliferation and curcumin effects on endometrial stromal cells were assessed by the MTT assay and Hematoxylin and Eosin staining. For cell cycle analysis, phase distribution was detected by flow cytometry. Vascular endothelial growth factor (VEGF) protein expression was examined using immunohistochemistry staining. Apoptosis was assessed using Annexin Vfluorescein isothiocyanate staining. The results indicated that the treatment of curcumin decreased human ectopic and eutopic stromal cell growth. Following treatment with curcumin, human endometriotic stromal cells demonstrated an increased percentage of G1phase cells and decreased percentages of Sphase cells, particularly in the group treated with 50 µmol/l curcumin. Treatment with curcumin additionally decreased expression of VEGF. The data provide evidence that curcumin reduces cell survival in human endometriotic stromal cells, and this may be mediated via downregulation of the VEGF signaling pathway.
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Curcumina/farmacología , Endometriosis/metabolismo , Transducción de Señal/efectos de los fármacos , Factores de Crecimiento Endotelial Vascular/metabolismo , Adulto , Apoptosis , Biomarcadores , Proliferación Celular/efectos de los fármacos , Curcumina/química , Endometriosis/patología , Femenino , Citometría de Flujo , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismo , Adulto JovenRESUMEN
The untranslated regions (UTRs) of mRNA contain important features that are relevant to the post-transcriptional and translational regulation of gene expression. Most studies of bacterial UTRs have focused on the 5'regions; however, 3'UTRs have recently emerged as a new class of post-transcriptional regulatory elements. 3'UTRs were found to regulate the decay and translation initiation in their own mRNAs. In addition, 3'UTRs constitute a rich reservoir of small regulatory RNAs, regulating target gene expression. In the current review, we describe several recently discovered examples of bacterial regulatory 3'UTRs, discuss their modes of action, and illustrate how they facilitate gene regulation in various environments.
RESUMEN
Delayed and failed bone union following fracture is a common clinical complication that requires treatment in orthopedics. Cell-based therapies and tissue-engineering approaches are potential therapeutic strategies for bone repair and fracture healing. However, the effect of adenovirus expressing bone morphogenetic protein-2 (Ad-BMP-2) on the osteogenic ability of human mesenchymal stem cells (hMSCs) has remained to be fully elucidated. Therefore, in the present study, hMSCs were transduced using Ad-BMP-2 to assess the effects of its application and to determine whether Ad-BMP-2 promotes the osteogenic differentiation of hMSCs. The purity of the hMSC cultures was assessed using flow cytometric analysis. In order to assess the osteogenic activity, alkaline phosphatase activity (ALP) was measured and to estimate the osteoblastic mineralization and calcification, von Kossa staining for phosphates was performed. Cells positive for Src homology 2 domain were determined to be hMSCs and the presence of CD34 was used to distinguish hematopoietic lineages. Following treatment, the Ad-BMP-2 and control group had significantly increased ALP levels (P<0.05). Compared to the blank group and the group transfected with adenoviral vector containing LacZ, the phosphate deposition in the Ad-BMP-2 group and the positive control group treated with dexamethasone was markedly increased. The results of the present study suggested that Ad-BMP-2 promotes osteogenic differentiation in hMSCs and may have a potential application in treating delayed union and nonunion following bone fracture.