RESUMEN
During eukaryotic ribosome biogenesis, pre-ribosomes travel from the nucleolus, where assembly is initiated, to the nucleoplasm and then are exported to the cytoplasm, where assembly concludes. Although nuclear export of pre-ribosomes has been extensively investigated, the release of pre-ribosomes from the nucleolus is an understudied phenomenon. Initial data indicate that unfolded rRNA interacts in trans with nucleolar components and that, when rRNA folds due to ribosomal protein (RP) binding, the number of trans interactions drops below the threshold necessary for nucleolar retention. To validate and expand on this idea, we performed a bioinformatic analysis of the protein components of the Saccharomyces cerevisiae ribosome assembly pathway. We found that ribosome biogenesis factors (RiBi factors) contain significantly more predicted trans interacting regions than RPs. We also analyzed cryo-EM structures of ribosome assembly intermediates to determine how nucleolar pre-ribosomes differ from post-nucleolar pre-ribosomes, specifically the capacity of RPs, RiBi factors, and rRNA components to interact in trans. We observed a significant decrease in the theoretical trans-interacting capability of pre-ribosomes between nucleolar and post-nucleolar stages of assembly due to the release of RiBi factors from particles and the folding of rRNA. Here, we provide a mechanism for the release of pre-ribosomes from the nucleolus.
Asunto(s)
Nucléolo Celular , Ribosomas , Saccharomyces cerevisiae , Nucléolo Celular/metabolismo , Núcleo Celular/metabolismo , Proteínas Ribosómicas/metabolismo , Ribosomas/metabolismo , ARN Ribosómico/metabolismo , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
Large ribosomal subunit precursors (pre-LSUs) are primarily synthesized in the nucleolus. At an undetermined step in their assembly, they are released into the nucleoplasm. Structural models of yeast pre-LSUs at various stages of assembly have been collected using cryo-EM. However, which cryo-EM model is closest to the final nucleolar intermediate of the LSU has yet to be determined. To elucidate the mechanisms of the release of pre-LSUs from the nucleolus, we assayed effects of depleting or knocking out two yeast ribosome biogenesis factors (RiBi factors), Puf6 and Nog2, and two ribosomal proteins, uL2 and eL43. These proteins function during or stabilize onto pre-LSUs between the late nucleolar stages to early nucleoplasmic stages of ribosome biogenesis. By characterizing the phenotype of these four mutants, we determined that a particle that is intermediate between the cryo-EM model State NE1 and State NE2 likely represents the final nucleolar assembly intermediate of the LSU. We conclude that the release of the RiBi factors Nip7, Nop2 and Spb1 and the subsequent stabilization of rRNA domains IV and V may be key triggers for the release of pre-LSUs from the nucleolus.
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Proteínas Ribosómicas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Proteínas Ribosómicas/metabolismo , Subunidades Ribosómicas Grandes/metabolismo , Subunidades Ribosómicas Grandes de Eucariotas/metabolismo , ARN Ribosómico/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
During translation, nascent polypeptide chains travel from the peptidyl transferase center through the nascent polypeptide exit tunnel (NPET) to emerge from 60S subunits. The NPET includes portions of five of the six 25S/5.8S rRNA domains and ribosomal proteins uL4, uL22, and eL39. Internal loops of uL4 and uL22 form the constriction sites of the NPET and are important for both assembly and function of ribosomes. Here, we investigated the roles of eL39 in tunnel construction, 60S biogenesis, and protein synthesis. We show that eL39 is important for proper protein folding during translation. Consistent with a delay in processing of 27S and 7S pre-rRNAs, eL39 functions in pre-60S assembly during middle nucleolar stages. Our biochemical assays suggest the presence of eL39 in particles at these stages, although it is not visualized in them by cryo-electron microscopy. This indicates that eL39 takes part in assembly even when it is not fully accommodated into the body of pre-60S particles. eL39 is also important for later steps of assembly, rotation of the 5S ribonucleoprotein complex, likely through long range rRNA interactions. Finally, our data strongly suggest the presence of alternative pathways of ribosome assembly, previously observed in the biogenesis of bacterial ribosomal subunits.
Asunto(s)
Proteínas Ribosómicas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Microscopía por Crioelectrón , Modelos Moleculares , Péptidos/metabolismo , Pliegue de Proteína , ARN Ribosómico/metabolismo , Proteínas Ribosómicas/metabolismo , Subunidades Ribosómicas Grandes de Eucariotas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
Background and Objectives: Mutations in succinate dehydrogenase (SDH) and fumarate hydratase (FH) give rise to various familial cancer syndromes, with these alterations being characteristic of certain types of histomorphologically specific leiomyomas that hold significant predictive value. Materials and Methods: This study presents two cases of uterine leiomyomas exhibiting rare histomorphological and genetic characteristics, which are crucial for prognosis and further treatment. Results: Distinct histopathological features such as marked nuclear atypia, intracellular eosinophilic globules, and abnormal intratumoral vessels raise suspicion for specific leiomyoma subtypes, which carry predictive significance for additional hereditary cancer syndromes. Immunohistochemical analysis confirmed FH/SDH deficiency in both patients, who underwent careful follow-up. Conclusions: This study describes two cases involving unusual leiomyomas, the histopathological characteristics of which may easily go unrecognized. These features hold predictive significance because their specific mutations point to additional hereditary cancer syndromes, highlighting the need for further examinations.
Asunto(s)
Fumarato Hidratasa , Leiomioma , Succinato Deshidrogenasa , Neoplasias Uterinas , Humanos , Femenino , Fumarato Hidratasa/deficiencia , Fumarato Hidratasa/genética , Neoplasias Uterinas/genética , Neoplasias Uterinas/patología , Succinato Deshidrogenasa/deficiencia , Succinato Deshidrogenasa/genética , Adulto , Leiomioma/genética , Leiomioma/patología , Persona de Mediana EdadRESUMEN
Uterine fibroids (leiomyomas and myomas) are the most common benign gynecological condition in patients presenting with abnormal uterine bleeding, pelvic masses causing pressure or pain, infertility and obstetric complications. Almost a third of women with fibroids need treatment due to symptoms. OBJECTIVES: In this review we present all currently available treatment modalities for uterine fibroids. METHODS: An extensive search for the available data regarding surgical, medical and other treatment options for uterine fibroids was conducted. REVIEW: Nowadays, treatment for fibroids is intended to control symptoms while preserving future fertility. The choice of treatment depends on the patient's age and fertility and the number, size and location of the fibroids. Current management strategies mainly involve surgical interventions (hysterectomy and myomectomy hysteroscopy, laparoscopy or laparotomy). Other surgical and non-surgical minimally invasive techniques include interventions performed under radiologic or ultrasound guidance (uterine artery embolization and occlusion, myolysis, magnetic resonance-guided focused ultrasound surgery, radiofrequency ablation of fibroids and endometrial ablation). Medical treatment options for fibroids are still restricted and available medications (progestogens, combined oral contraceptives andgonadotropin-releasing hormone agonists and antagonists) are generally used for short-term treatment of fibroid-induced bleeding. Recently, it was shown that SPRMs could be administered intermittently long-term with good results on bleeding and fibroid size reduction. Novel medical treatments are still under investigation but with promising results. CONCLUSIONS: Treatment of fibroids must be individualized based on the presence and severity of symptoms and the patient's desire for definitive treatment or fertility preservation.
Asunto(s)
Leiomioma , Humanos , Leiomioma/terapia , Leiomioma/cirugía , Femenino , Neoplasias Uterinas/terapia , Neoplasias Uterinas/cirugía , Neoplasias Uterinas/complicaciones , Histerectomía/métodos , Embolización de la Arteria Uterina/métodos , Miomectomía Uterina/métodosRESUMEN
Background and Objectives: Severe hemoperitoneum of ovarian bleeding origin is a rare but potentially life-threatening complication of transvaginal oocyte retrieval (TVOR) procedure. The study aimed to present a case series of surgically managed patients from our clinic with hemoperitoneum caused by ovarian bleeding after TVOR, as well as to perform a comprehensive literature review in order to summarize and analyze all published cases with this condition and their management. Materials and Methods: The data of 2939 patients, who underwent TVOR procedures for IVF/ICSI (in vitro fertilization, intracytoplasmic sperm injection) in our clinic between 2010 and 2021 were reviewed. Moreover, a systemic literature search was performed. Main outcome measures from the pooled analysis were incidence and risk factors, type of surgery, intraoperative finding and intervention leading to hemostasis. Results: In our Clinic 4 (0.136%), cases of hemoperitoneum due to ovarian bleeding were surgically managed. Moreover, 39 cases from 18 studies reported in the literature were identified. No risk factors besides lean women with PCOS were identified. In the pooled analysis, the bleeding symptoms appeared in 58.1% of patients within eight hours after TVOR and cumulatively in 81.4% cases during the 24 h after TVOR. The average time from TVOR to surgery was 27.19 ± 53.25 h. Hemostasis was mostly established using electrocoagulation, although few cases of ovariectomy were also reported. Embryo transfer at 60% of cases was postponed and embryos cryopreserved. Conclusions: Severe hemoperitoneum due to ovarian bleeding after TVOR is a rare event that should be treated by techniques of minimally invasive surgery whenever possible. Protocols should be developed to enable optimal management strategies for infertility patients. Embryos obtained should be cryopreserved.
Asunto(s)
Hemoperitoneo , Recuperación del Oocito , Masculino , Humanos , Femenino , Hemoperitoneo/etiología , Recuperación del Oocito/métodos , Estudios Retrospectivos , Semen , OvarioRESUMEN
BACKGROUND: Non-albicans Candida spp. are an emerging cause of hospital-acquired bloodstream infections, associated with high mortality due to the challenges in diagnosis and delayed treatment. OBJECTIVES: We aimed to investigate a cluster of healthcare-associated invasive candidiasis caused by C tropicalis and review the literature of healthcare-associated outbreaks or clusters caused by C tropicalis. METHODS: An investigation was performed to determine clinical presentation, treatment outcomes and the factors contributing to C tropicalis candidemia occurrence. We searched the Medline database via PubMed and Ovid using the keywords of "Candida tropicalis" combined with "outbreak" or "clustering" or "clusters," and we limited the search to studies conducted from January 1989 to January 2019. RESULTS: We report two related cases of C tropicalis candidemia among patients with AML following a period of neutropenia, who had erythematous skin rash as a first manifesting sign of candidiasis. C tropicalis was isolated from blood and skin cultures of both patients, which were identical by pulsed-field gel electrophoresis typing. Our systematic review of outbreaks caused by C tropicalis suggests that (a) most reported outbreaks have occurred in neonatal and adult ICUs; (b) patients who receive total parenteral therapy, antibiotics and those who have indwelling catheters and recent surgery are at high risk of infection; and (c) environmental and healthcare personnel surveillance suggest that cross-contamination is a major risk factor. CONCLUSION: Control of nosocomial outbreaks caused by C tropicalis should include better infection control measures, education of healthcare professionals especially working in adult and neonatal intensive care and haematology units.
Asunto(s)
Candida tropicalis/aislamiento & purificación , Candidemia/epidemiología , Candidiasis/epidemiología , Infección Hospitalaria/epidemiología , Brotes de Enfermedades , Hematología , Hospitales , Humanos , Control de Infecciones , Unidades de Cuidados Intensivos , Unidades de Cuidado Intensivo NeonatalRESUMEN
INTRODUCTION: Whipple disease is a rare infectious disease caused by the bacterium Tropheryma whipplei. The classic form affects gastrointestinal and musculoskeletal systems; but other forms may damage the heart, brain, or lungs. Due to non-specific and diverse clinical symptoms, diagnosis of Whipple disease is challenging and often late. Adequate and timely antibiotic treatment is essential for favorable outcome. CASE PRESENTATION: Here we present a case of a young woman admitted to the gynecological clinic for diagnostic laparoscopy for suspected haemato-/hydro- salpinx and peritoneal endometriosis. Macroscopic findings during laparoscopy revealed miliary whitish lesions in the pelvis and histopathology reported granulomatous salpingitis and peritonitis. She was complaining of intermittent abdominal pain, bloating and weight loss. Subsequently, the laparoscopy symptoms worsened and her general condition deteriorated. Differential diagnosis included infective agents such as Mycobacterium tuberculosis; in addition to sarcoidosis, granulomatosis with polyangiitis, and malignancies; all of which were excluded. Finally, Tropheryma whipplei was suspected, and after esophagogastroduodenoscopy with duodenal biopsy, long-term antibiotic treatment was initiated and the patient fully recovered. CONCLUSIONS: Although Whipple disease is rare, it is important to have a high level of awareness for Tropheryma whipplei infection. The localization and course of Whipple's disease may be unpredictable, but a favorable outcome is expected with adequate antibiotic treatment.
Asunto(s)
Antibacterianos , Peritonitis , Enfermedad de Whipple , Humanos , Femenino , Enfermedad de Whipple/diagnóstico , Enfermedad de Whipple/tratamiento farmacológico , Enfermedad de Whipple/patología , Adulto , Antibacterianos/uso terapéutico , Peritonitis/microbiología , Peritonitis/diagnóstico , Peritonitis/tratamiento farmacológico , Peritonitis/patología , Tropheryma/aislamiento & purificación , Diagnóstico DiferencialRESUMEN
INTRODUCTION: Toxoplasma gondii is an obligate intracellular parasite affecting a broad range of warm-blooded animals, including humans. Infection acquired during pregnancy can be transmitted to the fetus and leading to serious problems such as spontaneous abortion, stillbirth, or severe mental and/or physical handicaps in the child. The purpose of this study was to investigate the seroprevalence of Toxoplasma infection and related risk factors in pregnant woman. METHODOLOGY: The study enrolled 1200 serum samples of pregnant women from February-November 2017. Then the samples were tested for the presence of anti-T. gondii antibodies (Ab) using enzyme-linked immunosorbent assay. RESULTS: Out of the 1200 samples, 381 (31.7%) and 41 (3.4%) subjects were positive for IgG and IgM Ab, respectively. Among the evaluated risk factors, the seroprevalence of Toxoplasma infection was not related to the occupation in a significant way. However significant relationship was observed with factors such as; contact with soil, cats, consumption of raw washed vegetables, and washed hands before meals. CONCLUSIONS: According to the results, more than two-thirds of pregnant women are susceptible to Toxoplasma infection, hence training health care programs should be provided to prevent infection.
Asunto(s)
Aborto Espontáneo , Toxoplasma , Toxoplasmosis , Animales , Niño , Humanos , Femenino , Embarazo , Mujeres Embarazadas , Estudios Seroepidemiológicos , Anticuerpos Antiprotozoarios , Inmunoglobulina G , Estudios Transversales , Toxoplasmosis/epidemiología , Factores de Riesgo , Inmunoglobulina MRESUMEN
Upstream open-reading frames (uORFs) are potent cis-acting regulators of mRNA translation and nonsense-mediated decay (NMD). While both AUG- and non-AUG initiated uORFs are ubiquitous in ribosome profiling studies, few uORFs have been experimentally tested. Consequently, the relative influences of sequence, structural, and positional features on uORF activity have not been determined. We quantified thousands of yeast uORFs using massively parallel reporter assays in wildtype and ∆upf1 yeast. While nearly all AUG uORFs were robust repressors, most non-AUG uORFs had relatively weak impacts on expression. Machine learning regression modeling revealed that both uORF sequences and locations within transcript leaders predict their effect on gene expression. Indeed, alternative transcription start sites highly influenced uORF activity. These results define the scope of natural uORF activity, identify features associated with translational repression and NMD, and suggest that the locations of uORFs in transcript leaders are nearly as predictive as uORF sequences.
Asunto(s)
Biosíntesis de Proteínas , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Degradación de ARNm Mediada por Codón sin Sentido , Sistemas de Lectura Abierta/genética , Regiones no Traducidas 5'RESUMEN
INTRODUCTION: Trichomoniasis is the most common non-viral sexually transmitted infection that increases the risk of cervical cancer. Trichomonas vaginalis (T. vaginalis) can regulate the pro-inflammatory cytokine production in the host cells. Toll-like receptors (TLRs) are a family of the pattern recognition receptors (PRRs) of mammalian cells, expressed in various host cells and have an important role in recognizing pathogens, and pro-inflammatory responses. The aim of the present study is to investigate the role of TLR5 in cervical cancer cells (HeLa) and human vaginal epithelial cells (HVECs) exposed to T. vaginalis. METHODOLOGY: First, the cells and parasites were cultured in RPMI and trypticase yeast extract maltose (TYM), respectively. After adaption of parasite and epithelial cells by RPMI-TYM medium co-culture (9:1 vol/vol), HVECs and HeLa cells were stimulated with T. vaginalis trophozoites (24-hour incubation at 37 °C, 5% CO2). Following RNA extraction and cDNA synthesis, the gene expression levels of TLR5, IRAK1, and NF-κB were assessed using real-time PCR. Besides, the protein levels were measured using western blotting. All tests and controls were normalized using ß-actin as a housekeeping control. RESULTS: Real-time PCR results showed an increased gene expression of TLR5, IRAK1, and NF-κB in T. vaginalis exposed HVECs and HeLa cells compared to the control group (p < 0.05). Additionally, western blot analysis showed a statistically significant increase in TLR5, and NF-κB proteins in both groups after exposure to the parasite (p < 0.05). CONCLUSIONS: These findings provide insight into the host-parasite interaction, and the results indicated that T. vaginalis could stimulate TLR5 and activate related pathways.
Asunto(s)
Trichomonas vaginalis , Neoplasias del Cuello Uterino , Animales , Femenino , Humanos , Células Epiteliales , Células HeLa , Quinasas Asociadas a Receptores de Interleucina-1 , FN-kappa B , Receptor Toll-Like 5 , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/parasitologíaRESUMEN
INTRODUCTION: Multi-organ dysfunction caused by thromboembolic complications may complicate the course of SARS-CoV-2 infection. Most patients require anticoagulant therapy which predisposes them to the development of hemorrhagic syndrome. In critically ill COVID-19 patients secondary infections due to opportunistic pathogens are associated with a high mortality rate. CASE REPORT: Herein, we present a COVID-19 patient with severe hemorrhage at unusual sites complicated with invasive candidiasis and an extensively drug-resistant (XDR) strain of Klebsiella enterobacter. CONCLUSIONS: Clinicians should be aware of the possibility for invasive fungal infections in severely ill patients with SARS-CoV-2 infection due to pre-existing conditions, risk factors, and COVID-19 associated pathological mechanisms. Management of invasive candidiasis is challenging because of the high prevalence of comorbidities, risk of toxicities, and drug interactions.
Asunto(s)
COVID-19 , Candidiasis Invasiva , COVID-19/complicaciones , Candidiasis , Candidiasis Invasiva/tratamiento farmacológico , Hemorragia , Humanos , Klebsiella , SARS-CoV-2RESUMEN
OBJECTIVES: To evaluate the impact of pharmacological and surgical endometriosis treatment on IVF reproductive outcomes in patients with primary infertility. MATERIAL AND METHODS: The study, conducted over a five year period, included 73 patients with endometriosis associated primary infertility subjected to 77 cycles. Group I included patients treated for endometriosis before the IVF (subgroups A: surgical and pharmacological treatment and B: only surgical treatment). Group II included patients immediately subjected to IVF. Assessed outcomes were pregnancy rate (PR) per started cycle, fertilization rate (FR), implantation rate (IR) and live birth rate (LBR). RESULTS: Group IA included 25 patients, Group IB 21 and Group II 27 patients. FR and IR showed no significant differences between groups. PR was significantly higher in the Group I than Group II (49% vs 25%, p = 0.030). PR per started cycle was the highest in the Group IA and the lowest in the Group II (p = 0.040). LBR was significantly higher in whole Group I (p = 0.043) and subgroup IA (p = 0.020) than Group II. Group IA and IB did not differ regarding examined outcomes. Regression analysis showed that endometriosis pretreatment method can impact both achieving pregnancy (p = 0.036) and having a live born child (p = 0.008) after IVF. The combined surgical and pharmacological endometriosis treatment, shorter infertility duration, lower EFI score, using long protocol with FSH+HMG gonadotropins increase the probability of successful IVF. CONCLUSIONS: A combined surgical and pharmacological endometriosis treatment had a positive impact on IVF reproductive outcomes, both on pregnancy and on live birth rates.
Asunto(s)
Endometriosis , Infertilidad Femenina , Embarazo , Femenino , Niño , Humanos , Endometriosis/complicaciones , Endometriosis/cirugía , Fertilización In Vitro/métodos , Infertilidad Femenina/etiología , Infertilidad Femenina/terapia , Estudios Prospectivos , Estudios Retrospectivos , Índice de EmbarazoRESUMEN
INTRODUCTION: Drug-induced liver injury (DILI) is one of the most common causes of liver damage. A large number of drugs, dietary supplements, and herbal medications can cause hepatotoxicity. In some situations, it is difficult to distinguish between DILI and autoimmune hepatitis, especially when the mechanism is immune-mediated. Albendazole is a drug that has been used for decades for the treatment of parasitic infections in humans. One of the side effects is liver enzyme elevation, but rarely requires the discontinuation of therapy. Previous experience has shown that hypersensitivity is the most common mechanism of albendazole hepatotoxicity. CASE REPORT: Here we presented a paediatric patient in whom albendazole induced severe liver injury. In laboratory analyses, in addition to markedly elevated transaminases and parameters of cholestasis, there was also a significant increase in IgG, so autoimmune hepatitis was considered. Even though the liver histology indicated toxic liver disease, prednisolone was started. Corticosteroid therapy resulted in the complete normalization of liver function, as well as IgG. With the cessation of corticosteroid therapy, transaminases, bilirubin and gamma-glutamyl transferase (GGT) remained within normal levels, but an increase in anti-smooth muscle antibodies (SMA) was noted in immunological analyses after one year of follow-up. CONCLUSIONS: Immune-mediated hepatotoxicity from albendazole is one possible mechanism of liver injury. The use of albendazole in the treatment of parasitic infections, especially in children, requires close monitoring. The question remains as to whether albendazole is a drug that can induce autoimmune hepatitis in the paediatric population.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Hepatitis A , Hepatitis Autoinmune , Humanos , Niño , Hepatitis Autoinmune/tratamiento farmacológico , Hepatitis Autoinmune/etiología , Hepatitis Autoinmune/patología , Albendazol/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Aguda , Inmunoglobulina G , Transaminasas , CorticoesteroidesRESUMEN
The data regarding the role of progesterone (P4) in reproductive events of endometriosis patients are limited. This prospective study aimed to examine the predictive value of basal P4 serum levels for successful in vitro fertilization (IVF) in patients with primary infertility and endometriosis. The study included 73 patients divided according to endometriosis treatment (surgery vs. control-no treatment). The general data, basal hormonal status, and pregnancy rates were determined for every patient. Clinical pregnancy was achieved in 40.3% of patients, and more often in patients treated for endometriosis before IVF. The regression analysis showed that higher basal P4 serum levels were associated with achieving pregnancy through IVF. When regression was adjusted for the patient and IVF characteristics, higher basal P4 serum levels were associated with pregnancy achievement in both groups of women, along with the basal serum levels of FSH, LH, and AMH; EFI score; and stimulation protocol. The ROC analysis showed that the basal P4 serum level for successful IVF should be ≥0.7ng/mL. The basal P4 serum level cut-off for IVF success in endometriosis patients was determined for the first time. Constructed models for IVF success prediction emphasize the importance of determining the basal P4 serum levels for the personalized treatment of endometriosis-related infertility.
RESUMEN
The protein composition and structure of assembling 60S ribosomal subunits undergo numerous changes as pre-ribosomes transition from the nucleolus to the nucleoplasm. This includes stable anchoring of the Rpf2 subcomplex containing 5S rRNA, rpL5, rpL11, Rpf2 and Rrs1, which initially docks onto the flexible domain V of rRNA at earlier stages of assembly. In this work, we tested the function of the C-terminal domain (CTD) of Rpf2 during these anchoring steps, by truncating this extension and assaying effects on middle stages of subunit maturation. The rpf2Δ255-344 mutation affects proper folding of rRNA helices H68-70 during anchoring of the Rpf2 subcomplex. In addition, several assembly factors (AFs) are absent from pre-ribosomes or in altered conformations. Consequently, major remodeling events fail to occur: rotation of the 5S RNP, maturation of the peptidyl transferase center (PTC) and the nascent polypeptide exit tunnel (NPET), and export of assembling subunits to the cytoplasm.
Asunto(s)
Ribonucleoproteínas/metabolismo , Subunidades Ribosómicas Grandes/metabolismo , Rotación , Saccharomyces cerevisiae/metabolismo , Transporte Activo de Núcleo Celular , Núcleo Celular/metabolismo , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/genética , Mutación/genética , Dominios Proteicos , Pliegue de Proteína , Proteínas de Unión al ARN/química , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/ultraestructura , Subunidades Ribosómicas Grandes/química , Saccharomyces cerevisiae/crecimiento & desarrollo , Saccharomyces cerevisiae/ultraestructura , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/ultraestructuraRESUMEN
Lyme endocarditis is extremely rare manifestation of Lyme disease. The clinical manifestations of Lyme endocarditis are non-specific and can be very challenging diagnosis to make when it is the only manifestation of the disease. Until now, only a few cases where reported. Physicians should keep in mind the possibility of borrelial etiology of endocarditis in endemic areas. Appropriate valve tissue sample should be sent for histopathology, culture, and PCR especially in case of endocarditis of unknown origin PCR on heart valve samples is recommended. With more frequent PCR, Borrelia spp. may be increasingly found as a cause of infective endocarditis. Prompt diagnosis and treatment of Lyme carditis may prevent surgical treatment and pacemaker implantations. Due to climate change and global warming Lyme disease is a growing problem. Rising number of Lyme disease cases we can expect and rising number of Lyme endocarditis.
RESUMEN
Cryptococcosis is an opportunistic fungal infection causes significant disease predominantly in immunocompromised patients. Here we present an excepcional case of disseminated cryptococcosis with pulmonary and cerebral involvement in an immunocompetent patient with no apparent predisposing factors at the time of hospital admission. We described a case of an apparently immunocompetent 66-years old man admitted to hospital with a one-month history of cough, fever and vertigo. During hospitalization, thorax imaging was suggestive of lung metastasis, therefore, he went through several investigations. During hospitalization, he developed neurological symptoms and subsequently underwent a lumbar puncture. Cerebrospinal fluid (CSF) culture was positive for Cryptococcus spp. isolated on Sabouraud's dextrose agar and bird seed agar. In addition, the direct microscopy examination was positive for the India ink test, as well as with the latex agglutination test for cryptococcal polysaccharide antigen (CrAg) in CSF, while serum CrAg was negative. Despite the absence of classic immunocompromising features, he was treated with amphotericin B and fluconazole due to suspected disseminated cryptococcal infection. Later, he was diagnosed with prostatic adenocarcinoma. Upon successful completion of treatment for disseminated cryptococcosis, the patient underwent radical prostate ablation surgery as a treatment forprostatic adenocarcinoma. This exceptional case emphasizes the high degree of suspicion of atypical infections, and in these cases, it is particularly important to consider fungal infections in hitherto healthy patients with no apparent predisposing factors. Although Cryptococcus spp. is predominantly reported in patients with hematological malignancies, cryptococcosis investigation should also be considered as part of the initial workup of patients with a new diagnosis of a solid tumour prior to chemotherapy or radiotherapy.
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Adenocarcinoma/diagnóstico , Criptococosis/diagnóstico , Neoplasias de la Próstata/diagnóstico , Adenocarcinoma/inmunología , Adenocarcinoma/cirugía , Anciano , Anfotericina B/administración & dosificación , Antifúngicos/administración & dosificación , Criptococosis/tratamiento farmacológico , Criptococosis/inmunología , Fluconazol/administración & dosificación , Humanos , Huésped Inmunocomprometido , Masculino , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/cirugíaRESUMEN
INTRODUCTION: Management of pyogenic spinal infections (PSI) after the development of neurological deficit has not been specifically addressed in the literature. We aimed to describe real-life clinical outcomes of PSI in patients admitted to an intensive care unit with neurological deficit and identify factors associated with good prognosis. METHODOLOGY: Consecutive patients admitted to ICU with a possible diagnosis of spinal infection over five years' period were included. Descriptive statistics were performed to examine the demographics and clinical parameters. RESULTS: The majority (71%) of patients were male. The mean age was 57.4 years (27-79), and 71% were > 50 years old. At least one underlying risk factor was identified in 68% of the patients; the most common comorbidity was diabetes mellitus (DM). All patients have presented with fever accompanied by a neurological deficit (86%) and back pain (79%). A complete recovery was achieved in 25% of patients. However, the majority of patients had adverse outcomes with 21.4% mortality, and 43% remaining neurological sequelae. Increased age with a cut-off of 65 years and pre-existing DM were identified as being associated with poor outcome. CONCLUSION: Mortality among patients admitted to ICU with PSI was significantly higher than reported in the literature. The residual neurological deficit was common, one-third of patients had remaining neurological sequelae, and only one-fourth had complete recovery. Increased age and background DM were the most important determinants of poor clinical outcome. The impact of DM appears to be much more important than currently recognised in this population.
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Discitis/epidemiología , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/aislamiento & purificación , Adulto , Anciano , Estudios Transversales , Discitis/mortalidad , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Serbia/epidemiología , Infecciones Estafilocócicas/mortalidadRESUMEN
INTRODUCTION: In the Europe, the number of tick-borne encephalitis (TBE) has been increased in the last decade, and the number of endemic areas has been also increased and is still growing. In the present case series, we present clinical and socio-epidemiological data of patients with TBE hospitalized in the period of TBE virus epidemic in Serbia. METHODOLOGY: A case series was conducted in Serbia in 2017. Patients with confirmed TBE were included in the study. Biochemical and serological analysis of blood and CSF, as well as radiological imaging (CT and MRI) were done. RESULTS: In total, 10 patients with TBE were included in the study. M:F ratio was 1.5:1, while average age was 45.1 years. Half of the patients had severe clinical picture. Endocranial CT scan and MRI did not reveal any abnormality, except in the patient with the most severe CNS infection (meningoencephalomyelitis). Mean value of sedimentation and CRP was slightly elevated (29.6 mm/1hours and 20.1 mg/L, respectively) in 80% of the patients, although elevation was almost negligible. The average number of leucocytes in the cerebrospinal fluid (CSF) was 171×106/L, the mean value of the CSF protein was 1.1g/L. There were no fatal outcomes. CONCLUSION: Since other CNS infections have similar clinical picture and CSF finding as TBE, serological analysis for TBE should be included in routine diagnostic practice.