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1.
PLoS Genet ; 19(11): e1010492, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37939109

RESUMO

Heterochromatin is a condensed chromatin structure that represses transcription of repetitive DNA elements and developmental genes, and is required for genome stability. Paradoxically, transcription of heterochromatic sequences is required for establishment of heterochromatin in diverse eukaryotic species. As such, components of the transcriptional machinery can play important roles in establishing heterochromatin. How these factors coordinate with heterochromatin proteins at nascent heterochromatic transcripts remains poorly understood. In the model eukaryote Schizosaccharomyces pombe (S. pombe), heterochromatin nucleation can be coupled to processing of nascent transcripts by the RNA interference (RNAi) pathway, or to other post-transcriptional mechanisms that are RNAi-independent. Here we show that the RNA polymerase II processivity factor Spt5 negatively regulates heterochromatin in S. pombe through its C-terminal domain (CTD). The Spt5 CTD is analogous to the CTD of the RNA polymerase II large subunit, and is comprised of multiple repeats of an amino acid motif that is phosphorylated by Cdk9. We provide evidence that genetic ablation of Spt5 CTD phosphorylation results in aberrant RNAi-dependent nucleation of heterochromatin at an ectopic location, as well as inappropriate spread of heterochromatin proximal to centromeres. In contrast, truncation of Spt5 CTD repeat number enhanced RNAi-independent heterochromatin formation and bypassed the requirement for RNAi. We relate these phenotypes to the known Spt5 CTD-binding factor Prf1/Rtf1. This separation of function argues that Spt5 CTD phosphorylation and CTD length restrict heterochromatin through unique mechanisms. More broadly, our findings argue that length and phosphorylation of the Spt5 CTD repeat array have distinct regulatory effects on transcription.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Fosforilação , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Heterocromatina/genética , Heterocromatina/metabolismo , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Fatores de Elongação da Transcrição/genética , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Sequências Repetidas Terminais , Interferência de RNA
2.
Dig Dis Sci ; 68(3): 736-743, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36352078

RESUMO

INTRODUCTION: Endoscopic procedures place a great deal of muscular strain on providers, especially over the span of their careers. In this study we quantitatively analyzed the effects of patient factors such as age, body mass index, and sex on the ergonomics of endoscopists performing colonoscopies. METHODS: Surface electromyography (sEMG) was used to measure ergonomic strain of physicians while performing colonoscopies in several key muscle groups. The percent of the maximum voluntary contraction (%MVC) was used as a measure of muscular strain. Data was then analyzed based on the patient characteristics above. RESULTS: Endoscopists performing colonoscopies on female patients (n = 47) experienced significantly higher ergonomic strain in their right trapezius and right posterior forearm muscle groups when compared to colonoscopies performed on males (n = 35) (%MVC R-trapezius: Male: 8.2; Female: 8.9; p = 0.048); (%MVC R-posterior forearm: Male: 10.4; Female: 11.6; p = 0.0006). Operators experienced greater strain in the same muscle groups when performing colonoscopies on patients with BMI ≤ 25 (n = 25) when compared to patients with BMI > 25 (n = 57) (%MVC R-trapezius: BMI < 25: 9.7; BMI ≥ 25: 8.2; p = 0.0002); (%MVC R-posterior forearm: BMI < 25: 11.9; BMI ≥ 25: 10.8; p = 0.0001). CONCLUSION: Physicians experienced greater ergonomic strain when performing colonoscopies on female patients and on patients with a BMI < 25. We believe that these factors potentially impact the tortuosity of the colon and therefore influence the difficulty of navigating the endoscope. These results may aid physicians in gauging the anticipated difficulty of colonoscopies based on patient factors. Increased awareness of their posturing and ergonomics during challenging cases will alleviate musculoskeletal injuries in the long run.


Assuntos
Músculo Esquelético , Médicos , Humanos , Masculino , Feminino , Eletromiografia , Ergonomia , Colonoscopia
3.
Chem Biodivers ; 19(6): e202200025, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35621714

RESUMO

Several species of the genus Eucalyptus are used in many traditional medicine systems for the treatment of respiratory tract infections, colds, flu, sore throats, and bronchitis. The genus Eucalyptus (Myrtaceae) is a well-known natural source of bioactive phloroglucinols. These polyphenolic compounds bear an aromatic phenyl ring with three hydroxy groups (1,3,5-trihydroxybenzene) which have been exhibiting a variety of biological activities such as antimicrobial, anticancer, anti-allergic, anti-inflammatory, and antioxidant activities. This review summarizes the literature published from 1997 until the end of 2021 and addresses the structure diversity of phloroglucinols isolated from Eucalyptus species and their biological activities. Phloroglucinol-terpene adducts are the main class of compounds that have been reported in this genus.


Assuntos
Eucalyptus , Myrtaceae , Eucalyptus/química , Medicina Tradicional , Floroglucinol/química , Extratos Vegetais/química
4.
Surg Endosc ; 36(7): 5104-5109, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34845543

RESUMO

INTRODUCTION: Up to 89% of physicians who routinely perform endoscopy experience some type of musculoskeletal pain. In this study, we sought to quantitatively analyze provider factors that influence ergonomic strain during live endoscopic procedures. METHODS: Surface electromyography (sEMG) was used to measure ergonomic strain on physicians while performing upper and lower endoscopies. EMG data were normalized to a maximal voluntary contraction (MVC) recording for each muscle group, yielding a %MVC value. Subgroup analyses were performed based on glove size, physician training level, specialty, and handedness. RESULTS: A total of 165 upper (n = 68) and lower (n = 97) endoscopies were recorded. Endoscopists with small hand sizes had significantly higher ergonomic strain in the left anterior and posterior forearm muscle compartments as compared to endoscopists with medium or large hands (%MVC L-anterior: small: 9.1 ± 1.1; medium: 6.4 ± 1.2; large: 5.9 ± 1.6; p < 0.001); (%MVC L-posterior: small: 12.0 ± 0.8; medium: 9.4 ± 1.3; large: 8.8 ± 1.4; p < 0.001). Additionally, upper body muscle groups had significantly higher ergonomic strain in endoscopists with less lifetime endoscopic experience (%MVC R-trapezius: expert: 8.4 ± 1.2; novice: 9.3 ± 1.2; p < 0.05); (%MVC R-deltoid: expert: 6.1 ± 1.4; novice: 8.5 ± 1.3; p < 0.001). There were no significant ergonomic differences between surgeons or gastroenterologists and no differences between right- and left-handed dominant individuals. CONCLUSIONS: Endoscopists with small hands experienced great ergonomic strain in their left forearm. Our data support the widely held belief that "one size does not fit all" and will hopefully spark change in the design of future endoscopes by device manufacturers. Our data also support that the experience level of the endoscopist contributed significantly to ergonomic performance, likely due to postural differences leading to decreased upper body strain. Therefore, it remains critically important to educate young proceduralists on strategies for ergonomic relief early in his or her endoscopic training program that can ameliorate ergonomic strain that accrues over the lifetime of a physician's career.


Assuntos
Laparoscopia , Cirurgiões , Eletromiografia , Ergonomia , Feminino , Humanos , Masculino , Músculo Esquelético/fisiologia
5.
Tanaffos ; 19(3): 250-255, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33815546

RESUMO

BACKGROUND: Intensive care unit acquired weakness (ICUAW) is a known complication in ICU patients, especially in those with severe underlying diseases. The cause and pathogenesis of ICUAW are still unknown. This study examined the incidence rate of ICUAW in intensive care units (ICUs) of the Masih-Daneshvari Hospital. MATERIALS AND METHODS: This descriptive-comparative study was conducted on 160 patients admitted in the ICUs, including an acute respiratory infectious ICU (TB-ICU) and medical ICU. The total number of patients was 80 in each of the ICUs. Demographic information was obtained from the patients after the initial examination and Medical Research Council (MRC) score was done on daily basis. EMG was performed on the 2nd and 8th days of the admission. ICUAW diagnosis was used in cases with MRC scores under 48. RESULTS: Among the patients, 68.6% were male and the mean age was 59.13±18. 68 years. The final outcomes were 48.4% mortality and 51.6% discharge, which were 41% and 59% in the TB-ICU and 56.7% and 43.3% in the medical ICU, respectively. By defining electromyography as the gold standard, the sensitivity and specificity of ICUAW diagnosis based on the MRC score definition were about 70% and 83%, respectively. The comparison ICUAW patients in the two ICUs in terms of mortality showed no significant difference between them. CONCLUSION: It is concluded that nearly half of ICU-admitted patients develop ICUAW that causes a higher mortality rate. Therefore, new plans should be developed to reduce the rate of ICUAW and subsequent death, as well as other possible morbidities.

6.
Minim Invasive Surg ; 2018: 4815761, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29552358

RESUMO

Recent technological progress offers the opportunity to significantly transform conventional open surgical procedures in ways that allow minimally invasive surgery (MIS) to be accomplished by specific operative instruments' entry into the body through key-sized holes rather than large incisions. Although MIS offers an opportunity for less trauma and quicker recovery, thereby reducing length of hospital stay and attendant costs, the complex nature of this procedure makes it difficult to master, not least because of the limited work area and constricted degree of freedom. Accordingly, this research seeks to design a Teach and Playback device that can aid surgical training by key-framing and then reproducing surgical motions. The result is an inexpensive and portable Teach and Playback laparoscopic training device that can record a trainer's surgical motions and then play them back for trainees. Indeed, such a device could provide a training platform for surgical residents generally and would also be susceptible of many other applications for other robot-assisted tasks that might require complex motion training and control.

7.
Minim Invasive Surg ; 2016: 5624630, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27313884

RESUMO

Due to its inherent complexity such as limited work volume and degree of freedom, minimally invasive surgery (MIS) is ergonomically challenging to surgeons compared to traditional open surgery. Specifically, MIS can expose performing surgeons to excessive ergonomic risks including muscle fatigue that may lead to critical errors in surgical procedures. Therefore, detecting the vulnerable muscles and time-to-fatigue during MIS is of great importance in order to prevent these errors. The main goal of this study is to propose and test a novel measure that can be efficiently used to detect muscle fatigue. In this study, surface electromyography was used to record muscle activations of five subjects while they performed fifteen various laparoscopic operations. The muscle activation data was then reconstructed using recurrence quantification analysis (RQA) to detect possible signs of muscle fatigue on eight muscle groups (bicep, triceps, deltoid, and trapezius). The results showed that RQA detects the fatigue sign on bilateral trapezius at 47.5 minutes (average) and bilateral deltoid at 57.5 minutes after the start of operations. No sign of fatigue was detected for bicep and triceps muscles of any subject. According to the results, the proposed novel measure can be efficiently used to detect muscle fatigue and eventually improve the quality of MIS procedures with reducing errors that may result from overlooked muscle fatigue.

8.
Oral Health Dent Manag ; 12(3): 186-90, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24352312

RESUMO

AIMS: Etoricoxib is a second-generation selective COX-2 inhibitor. There are a few researches investigating analgesic effect of Etoricoxib in dentistry. METHODS: This randomized, double-blind, active-control study included sixty patients with clinical pulpal diagnosis of necrosis of the first mandibular molar and an associated periapical radiolucency who experienced severe pain (more than 60 out of 100 in scale of Visual Analog Scale (VAS). The patients were equally randomized into four groups, who received 60 mg etoricoxib (group 1), 90 mg etoricoxib (group 2), 120 mg etoricoxib (group 3), and 400 mg ibuprofen (group 4). All patients randomly received a single dose of the drug after the first session of the root canal therapy. Using VAS, the severity of pain was recorded 2, 4, 6, 12, 24, 48, and 72 hours after the drug was administered. RESULTS: Changing trends of pain over the time was significant for all groups (P=0.003). In addition, there was not a significant difference between various study arms (P=0.146). CONCLUSION: The results showed that ibuprofen had a comparable effect with various dosage of etoricoxib and may remain as the choice analgesic for dental pulpal pain.

9.
J Cardiopulm Rehabil Prev ; 33(1): 42-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23221808

RESUMO

PURPOSE: The aim of this study was to assess the prevalence of impaired glucose metabolism in patients who attended hospital-based cardiac rehabilitation. METHODS: We performed a single-group cross-sectional study. In a 7-month period, from September 2010. The study was conducted in a cardiac rehabilitation setting at a university hospital. Overall, 273 patients, with an established diagnosis of ischemic heart disease, who were referred to the cardiac rehabilitation center, were included. The primary outcome measure was the prevalence of impaired glucose metabolism. We also compared cardiovascular disease risk profile among participants. RESULTS: One hundred twenty-one participants (44%) had diabetes mellitus, of which, for 80 patients, the diagnosis was previously established. Of the 193 patients without a previous diagnosis of diabetes, 52 patients (27%) had normal glucose levels, 41 (21.2%) had diabetes, 51 (26.4%) showed impaired glucose tolerance, and 49 (25.4%) had isolated impaired fasting glucose according to the American Diabetic Association criteria. Consistent with the World Health Organization criteria, 27 patients (14%) would have had isolated impaired fasting glucose and using fasting criteria alone, 22 patients would have had undiagnosed diabetes. CONCLUSION: Impaired fasting glucose and impaired glucose tolerance did not identify the same patients. It seems that both fasting plasma glucose and oral glucose tolerance test are necessary in the diagnosis of impaired glucose metabolism in patients with coronary artery disease.


Assuntos
Glicemia/metabolismo , Reabilitação Cardíaca , Intolerância à Glucose/epidemiologia , Encaminhamento e Consulta , Idoso , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/metabolismo , Estudos Transversais , Jejum/metabolismo , Feminino , Intolerância à Glucose/sangue , Teste de Tolerância a Glucose , Humanos , Incidência , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Instituições Filantrópicas de Saúde , Organização Mundial da Saúde
10.
Nephrourol Mon ; 5(5): 1001-4, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24693511

RESUMO

BACKGROUND AND AIM: The most common complication of renal transplantation is allograft dysfunction, which in some cases leads to graft loss. The role of graft nephrectomy in the management of transplant failure is controversial. The procedure remains associated with a significant morbidity and also mortality. Our main purpose was the comparison between clinical and pathological diagnosis of graft nephrectomy. PATIENTS AND METHODS: The documents of 88 patients who admitted for graft nephrectomy in Shariaty hospital for the last 25 years were reviewed. Slides of graft pathology were revised by an individual nephropathologist. Data was analyzed by SPSS 18 using ANOVA and Chi-square tests. RESULTS: THE PERCENTAGES OF CLINICAL DIAGNOSES FOR THE GRAFT NEPHRECTOMY ARE: chronic rejection (38%), graft infection (26%), gross hematuria (10%), acute rejection (10%), accelerated rejection (8%), hyper-acute rejection (4%) and thrombosis of the renal artery (4). On the other hand, the pathological diagnoses are: necrosis concomitant with thrombosis (35%), only necrosis (26%) and 5 (3) concomitant with 4 (3) in 16% of cases that means severe interstitial atrophy and fibrosis adjacent with acute cellular rejection and intramural vasculitis. CONCLUSIONS: Pathology included necrosis in about half of the graft nephrectomized patients. If the panel reactivity test is negative preoperatively, and there is no absolute indication for the operation, one may abstain from graft nephrectomy to save the patient, the morbidity and even the mortality of the procedure. On the other hand, the advantages of leaving the graft in situ are erythropoietin production, hydroxylation of calcidiol and maintenance of some residual diuresis.

11.
Biol Trace Elem Res ; 149(3): 419-24, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22555519

RESUMO

Two experiments were done in 2008 and 2009 to study the effects of magnetic field and silver nanoparticles on fodder maize (Zea mays L.). These experiments were done with seven treatments based on a randomized complete block design in four replications. The treatments were as follows: magnetic field and silver nanoparticles + Kemira fertilizer (T1), magnetic field and silver nanoparticles + Humax fertilizer (T2), magnetic field and silver nanoparticles (T3), Kemira fertilizer (T4), Librel fertilizer (T5), Humax fertilizer (T6), and a control (T7). Results showed that fresh yield was higher in treatments T3 and T4. Treatments T3 and T4 had increased maize fresh yields of 35 and 17.5 % in comparison to the control, respectively. The dry matter yield of those plants exposed to magnetic field and silver nanoparticles was significantly higher than that from any of the other treatments. Magnetic field and silver nanoparticle treatments (T3 and T1) showed higher percentages for ears, and the lowest percentages were found in treatments T7 and T5. In general, the soil conditions for crop growth were more favorable in 2009 than in 2008, which caused the maize to respond better to treatments tested in the study; therefore, treatments had more significant effects on studied traits in 2008 than in 2009.


Assuntos
Nanopartículas Metálicas/química , Prata/farmacologia , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento , Fertilizantes
12.
Am J Phys Med Rehabil ; 89(8): 660-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20463564

RESUMO

OBJECTIVE: To compare local corticosteroid with autologous blood injections for the short-term treatment of lateral elbow tendinopathy. DESIGN: A single blind, randomized clinical trial was performed in an outpatient clinic at a university hospital. Sixty patients aged 27-64 yrs with a new episode of tennis elbow were recruited. Thirty patients were randomized to methylprednisolone and 30 to autologous blood group over 1 yr. Severity of pain within last 24 hrs; limb function; pain and strength in maximum grip; disabilities of the arm, shoulder, and hand quick questionnaire (Quick DASH) scores; modified Nirschl scores; and pressure pain threshold were evaluated before injection and at 4 and 8 wks after injection. We analyzed our data with the chi and t test. RESULTS: Within-group analyses showed better results for autologous blood (all P values <0.001 except for grip strength, P = 0.005). In the corticosteroid group, differences in severity of pain (P = 0.008) and grip strength (P = 0.001) were significant. At 4 wks, between-group analyses showed superiority of autologous blood for severity of pain (P = 0.001), pain in grip (P = 0.002), pressure pain threshold (P = 0.031), and Quick DASH questionnaire score (P = 0.004). There were no significant differences in modified Nirschl score, grip strength, and limb function. At 8 wks, autologous blood was more effective in all the outcomes (all P values <0.001). CONCLUSIONS: Autologous blood was more effective in short term than the corticosteroid injection.


Assuntos
Corticosteroides/uso terapêutico , Transfusão de Sangue Autóloga , Metilprednisolona/uso terapêutico , Cotovelo de Tenista/terapia , Adulto , Feminino , Força da Mão , Humanos , Injeções Intra-Articulares , Masculino , Pessoa de Meia-Idade , Medição da Dor , Método Simples-Cego
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