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1.
J Biol Chem ; : 107505, 2024 Jun 27.
Article de Anglais | MEDLINE | ID: mdl-38944122

RÉSUMÉ

Archaeosine (G+) is an archaea-specific tRNA modification synthesized via multiple steps. In the first step, archaeosine tRNA guanine transglucosylase (ArcTGT) exchanges the G15 base in tRNA with 7-cyano-7-deazaguanine (preQ0). In Euryarchaea, preQ015 in tRNA is further modified by archaeosine synthase (ArcS). Thermococcus kodakarensis ArcS catalyzes a lysine-transfer reaction to produce preQ0-lysine (preQ0-Lys) as an intermediate. The resulting preQ0-Lys15 in tRNA is converted to G+15 by a radical S-adenosyl-L-methionine enzyme for archaeosine formation (RaSEA), which forms a complex with ArcS. Here, we focus on the substrate tRNA recognition mechanism of ArcS. Kinetic parameters of ArcS for lysine and tRNA-preQ0 were determined using purified enzyme. RNA fragments containing preQ0 were prepared from Saccharomyces cerevisiae tRNAPhe-preQ015. ArcS transferred 14C-labeled lysine to RNA fragments. Furthermore, ArcS transferred lysine to preQ0 nucleoside and preQ0 nucleoside 5'-monophosphate. Thus, the L-shaped structure and the sequence of tRNA are not essential for the lysine-transfer reaction by ArcS. However, the presence of D-arm structure accelerates the lysine-transfer reaction. Because ArcTGT from thermophilic archaea recognizes the common D-arm structure, we expected the combination of T. kodakarensis ArcTGT and ArcS and RaSEA complex would result in the formation of preQ0-Lys15 in all tRNAs. This hypothesis was confirmed using 46 T. kodakarensis tRNA transcripts and three H. volcanii tRNA transcripts. In addition, ArcTGT did not exchange the preQ0-Lys15 in tRNA with guanine or preQ0 base, showing that formation of tRNA-preQ0-Lys by ArcS plays a role in preventing the reverse reaction in G+ biosynthesis.

2.
Br J Ophthalmol ; 2024 Jan 30.
Article de Anglais | MEDLINE | ID: mdl-38290806

RÉSUMÉ

AIMS: To predict high-risk factors for zonular complications during cataract surgery due to pre-existing severe zonular dehiscence in eyes with pseudoexfoliation (PXF) syndrome. METHODS: 315 eyes of 315 consecutive patients with PXF scheduled for phacoemulsification surgery underwent preoperative examination of various ocular parameters using an anterior segment-optical coherence tomography and other devices. When zonular complications occurred during surgery due to zonular dehiscence, scleral fixation of the intraocular lens (IOL) or implantation of a capsular tension ring (CTR) was performed. High-risk factors for these intraoperative zonular complications were examined using classification-tree and logistic regression analyses. RESULTS: Of the 315 eyes, 31 (9.84%) underwent scleral IOL fixation or CTR implantation. High-risk factors identified by classification-tree analysis were a small pupillary diameter after mydriasis <6.30 mm, a shallow anterior chamber depth <2.074 mm and lens decentration >0.260 mm. Based on exact logistic regression analysis, the OR was 4.81-fold higher for eyes with poor mydriasis than for eyes without poor mydriasis (p=0.006, 95% CI 1.49 to 18.23), 23.99-fold higher for eyes with poor mydriasis and a shallow anterior chamber (p<0.001, 5.92 to 109.02) and 287.39-fold higher for eyes with poor mydriasis, a shallow chamber and great lens decentration (p<0.001, 50.46 to infinity). CONCLUSION: In eyes with PXF, high-risk factors for zonular complications during cataract surgery due to pre-existing severe zonular dehiscence were poor mydriasis, shallow anterior chamber and large lens decentration, suggesting the importance of evaluating these conditions preoperatively.

3.
Sci Rep ; 13(1): 21608, 2023 12 07.
Article de Anglais | MEDLINE | ID: mdl-38062060

RÉSUMÉ

No official clinical reference values have been established for MostGraph, which measures total respiratory resistance and reactance using the forced oscillation technique, complicating result interpretation. This study aimed to establish a reference range for MostGraph measurements and examine its usefulness in discriminating participants with asthma from controls (participants without any respiratory diseases). The study also aimed to investigate the effectiveness of deep learning in discriminating between the two aforementioned groups. To establish reference ranges, the MostGraph measurements of healthy controls (n = 215) were power-transformed to distribute the data more normally. After inverse transformation, the mean ± standard deviation × 2 of the transformed values were used to establish the reference ranges. The number of measured items outside the reference ranges was evaluated to discriminate patients with asthma (n = 941) from controls. Additionally, MostGraph measurements were evaluated using deep learning. Although reference ranges were established, patients with asthma could not be discriminated from controls. However, with deep learning, we could discriminate between the two groups with 78% accuracy. Therefore, deep learning, which considers multiple measurements as a whole, was more effective in interpreting MostGraph measurement results than use of reference ranges, which considers each result individually.


Sujet(s)
Asthme , Apprentissage profond , Humains , Valeurs de référence , Spirométrie/méthodes , Tests de la fonction respiratoire/méthodes , Asthme/diagnostic , Résistance des voies aériennes
4.
Ann Surg ; 2023 Oct 12.
Article de Anglais | MEDLINE | ID: mdl-37823278

RÉSUMÉ

OBJECTIVE: To create a recurrence prediction value (RPV) of high-risk factor and identify the patients with high risk of cancer recurrence. SUMMARY BACKGROUND DATA: There are several high-risk factors known to lead to poor outcomes. Weighting each high-risk factor based on their association with increased risk of cancer recurrence can provide a more precise understanding of risk of recurrence. METHODS: We performed a multi-institutional international retrospective analysis of patients with Stage II colon cancer patients who underwent surgery from 2010 to 2020. Patient data from a multi-institutional database were used as the Training data, and data from a completely separate international database from two countries were used as the Validation data. The primary endpoint was recurrence-free survival (RFS). RESULTS: A total of 739 patients were included from Training data. To validate the feasibility of RPV, 467 patients were included from Validation data. Training data patients were divided into RPV low (n = 564) and RPV high (n = 175). Multivariate analysis revealed that risk of recurrence was significantly higher in the RPV high than the RPV low (Hazard ratio (HR) 2.628; 95% confidence interval (CI) 1.887-3.660; P < 0.001). Validation data patients were divided into two groups (RPV low, n = 420) and RPV high (n = 47). Multivariate analysis revealed that risk of recurrence was significantly higher in the RPV high than the RPV low (HR 3.053; 95% CI 1.962-4.750; P < 0.001). CONCLUSIONS: RPV can identify Stage II colon cancer patients with high risk of cancer recurrence world-wide.

5.
J Biochem ; 175(1): 43-56, 2023 Dec 20.
Article de Anglais | MEDLINE | ID: mdl-37844264

RÉSUMÉ

TrmH is a eubacterial tRNA methyltransferase responsible for formation of 2'-O-methylguaosine at position 18 (Gm18) in tRNA. In Escherichia coli cells, only 14 tRNA species possess the Gm18 modification. To investigate the substrate tRNA selection mechanism of E. coli TrmH, we performed biochemical and structural studies. Escherichia coli TrmH requires a high concentration of substrate tRNA for efficient methylation. Experiments using native tRNA SerCGA purified from a trmH gene disruptant strain showed that modified nucleosides do not affect the methylation. A gel mobility-shift assay reveals that TrmH captures tRNAs without distinguishing between relatively good and very poor substrates. Methylation assays using wild-type and mutant tRNA transcripts revealed that the location of G18 in the D-loop is very important for efficient methylation by E. coli TrmH. In the case of tRNASer, tRNATyrand tRNALeu, the D-loop structure formed by interaction with the long variable region is important. For tRNAGln, the short distance between G18 and A14 is important. Thus, our biochemical study explains all Gm18 modification patterns in E. coli tRNAs. The crystal structure of E. coli TrmH has also been solved, and the tRNA binding mode of E. coli TrmH is discussed based on the structure.


Sujet(s)
Escherichia coli , Methyltransferases , Methyltransferases/génétique , Methyltransferases/métabolisme , Escherichia coli/génétique , Escherichia coli/métabolisme , Méthylation , T-RNA methyltransferases/composition chimique , ARN de transfert/composition chimique , Conformation d'acide nucléique
6.
J Gastrointest Surg ; 27(11): 2515-2525, 2023 11.
Article de Anglais | MEDLINE | ID: mdl-37740145

RÉSUMÉ

BACKGROUND: It is unclear how early- and delayed-onset organ/space surgical site infections (SSIs) affect the long-term prognosis of patients with colorectal cancer, who are potential candidates for adjuvant chemotherapy. This study aimed to investigate the association between the timing of SSI onset and clinical outcome. METHODS: This retrospective, multicenter cohort study evaluated patients who were diagnosed with high-risk stage II or III colorectal cancer and underwent elective surgery between 2010 and 2020. Five-year recurrence-free survival (RFS) was the primary endpoint and was compared between early SSI, delayed SSI (divided based on the median date of SSI onset), and non-SSI groups. RESULTS: A total of 2,065 patients were included. Organ/space SSI was diagnosed in 91 patients (4.4%), with a median onset of 6 days after surgery. The early-onset SSI group had a higher proportion of patients with Clavien-Dindo grade ≥IIIb SSI than the delayed-onset SSI. Patients who received adjuvant chemotherapy (AC) had earlier organ/space SSI onset than those who did not. The adjusted hazard ratio of 5-year RFS in the delayed-onset SSI was 2.58 (95% confidence interval: 1.43-4.65; p = 0.002): higher than that in the early-onset SSI, with the non-SSI as the reference. CONCLUSIONS: Delayed-onset organ/space SSI worsened long-term prognosis compared to early-onset, and this may be due to delayed initiation of AC. Patients who are clinically suspected of having lymph node metastasis might need additional intervention to prevent delays in commencing AC due to the delayed SSI.


Sujet(s)
Tumeurs colorectales , Infection de plaie opératoire , Humains , Infection de plaie opératoire/épidémiologie , Infection de plaie opératoire/étiologie , Infection de plaie opératoire/diagnostic , Études de cohortes , Études rétrospectives , Pronostic , Tumeurs colorectales/complications , Tumeurs colorectales/chirurgie , Facteurs de risque
7.
Jpn J Ophthalmol ; 67(6): 685-692, 2023 Nov.
Article de Anglais | MEDLINE | ID: mdl-37540326

RÉSUMÉ

PURPOSE: This study aimed to introduce a new technique for lowering intraocular pressure (IOP) using a multi-stent system after the implantation of a Baerveldt glaucoma implant (BGI) and evaluate its clinical effectiveness. STUDY DESIGN: Prospective case series. METHODS: Six patients with uncontrolled refractory glaucoma were enrolled between December 2021 and May 2022. Six 6-0 nylon sutures were preoperatively inserted into the tube of a BGI. These sutures were named "comet stents" (CSs). BGI implantation was performed, and the CSs were removed one-by-one whenever the IOP rose during the follow-up period. IOP was measured 30-60 min after the removal of each CS, and the reduction in IOP was recorded to assess the effect of CS removal. IOP reduction and the effect of CS removal on IOP reduction were evaluated for 6 months. The cut and trimmed stented tubes were examined with scanning electron microscopy, and the ratio of the patent cross-sectional area to the total luminal area (PCSA, %) and the luminal area occupation rate per stent (%) were calculated. RESULTS: The mean (±standard deviation) IOP decreased from 31.5 ± 2.8 mmHg at the baseline to 14.8 ± 8.3 mmHg at 1 month, 8.8 ± 4.7 mmHg at 3 months, and 9.2 ± 3.4 mmHg at 6 months. The IOP reduction induced by CS removal ranged from 0 to 19 mmHg. The mean PCSA was 52.7 ± 1.7%, and the mean luminal area occupation rate per stent was 7.9 ± 0.3%. CONCLUSION: The use of CSs is an effective technique for controlling IOP in a step-by-step manner after BGI surgery.


Sujet(s)
Implants de drainage du glaucome , Glaucome , Hypotension oculaire , Humains , Projets pilotes , Implantation de prothèse/méthodes , Acuité visuelle , Glaucome/chirurgie , Pression intraoculaire , Résultat thérapeutique , Endoprothèses , Études de suivi , Études rétrospectives
8.
Am J Case Rep ; 24: e939200, 2023 May 05.
Article de Anglais | MEDLINE | ID: mdl-37143323

RÉSUMÉ

BACKGROUND Coronary artery pseudoaneurysm is an extremely rare condition. In this report, we describe an 85-year-old hemodialysis male patient who developed a coronary artery pseudoaneurysm due to physical damage associated with coronary artery calcification. CASE REPORT An 85-year-old man on hemodialysis had undergone emergency percutaneous coronary intervention of the left anterior descending artery for acute coronary syndrome 9 years ago. He presented to the emergency room with a fever and chest pain and was admitted to the cardiology department with a urinary tract infection and acute coronary syndrome. On day 21 after admission, when the urinary tract infection had resolved, coronary angiography was performed, which revealed a pseudoaneurysm proximal to the left anterior descending artery stent. The patient was scheduled to undergo surgery due to the pseudoaneurysm's risk of rupture. Surgical manipulation was performed under cardiac arrest using the median sternotomy approach. A highly calcified coronary intima was found inside the pseudoaneurysm, which was completely ruptured on the proximal side of the pseudoaneurysm. The pseudoaneurysm was closed after endarterectomy. A coronary artery bypass graft was also performed in the great saphenous vein graft of the left anterior descending artery. Histopathological examination showed no obvious signs of infection, and a diagnosis of pseudoaneurysm was established. Postoperative contrast-enhanced computed tomography showed patency of the coronary artery bypass graft and no pseudoaneurysm recurrence. CONCLUSIONS Coronary artery pseudoaneurysms are extremely rare, but this case demonstrates that atherosclerotic changes can lead to the formation of a pseudoaneurysm in an elderly hemodialysis patient.


Sujet(s)
Syndrome coronarien aigu , Faux anévrisme , Maladie des artères coronaires , Humains , Mâle , Sujet âgé , Sujet âgé de 80 ans ou plus , Pontage aortocoronarien/effets indésirables , Maladie des artères coronaires/chirurgie , Maladie des artères coronaires/complications , Faux anévrisme/imagerie diagnostique , Faux anévrisme/étiologie , Faux anévrisme/chirurgie , Dialyse rénale/effets indésirables , Rupture
9.
Eye (Lond) ; 37(15): 3174-3179, 2023 10.
Article de Anglais | MEDLINE | ID: mdl-36928225

RÉSUMÉ

OBJECTIVE: To examine the incidence and characteristics of eyes with oblique astigmatism stratified by meridian, age, sex, and eye side (left to right). METHODS: One thousand eyes of 1000 patients with oblique corneal astigmatism underwent videokeratographic examination and was classified into 4 meridian categories: (1) 31°-45°, (2) 46°-59°, (3) 121°-135°, and (4) 136°-149°. Amounts of regular and irregular astigmatism, and the vertical/horizontal (Rx) and oblique astigmatism components (Ry) decomposed using vector analysis were compared among the 4 categories and age groups, and between sexes and eye sides. RESULTS: Incidences of the 4 meridian categories were similar and did not differ significantly among age groups or between sexes. The incidence was significantly greater in eyes in meridian categories 1 and 2 in the left eye and categories 3 and 4 in the right eye, and significantly greater in men in their 40 s and 50 s and in women in their 70 s and 80 s (P < 0.0001). The mean regular astigmatism, asymmetry and higher-order irregularity components, and Rx and absolute Ry significantly increased with age (P ≤ 0.0372). The mean regular and irregular astigmatism, and absolute Rx and Ry did not differ significantly among the 4 categories, or between sexes or left and right eyes. CONCLUSIONS: The incidence of oblique astigmatism was significantly greater in the temporal side meridians, and the incidence in women increased with age. The degree of oblique astigmatism increased with age, with an increase in irregular astigmatism.


Sujet(s)
Astigmatisme , Maladies de la cornée , Mâle , Humains , Femelle , Astigmatisme/étiologie , Prévalence , Cornée , Topographie cornéenne , Maladies de la cornée/complications
10.
J Surg Case Rep ; 2023(2): rjad051, 2023 Feb.
Article de Anglais | MEDLINE | ID: mdl-36818814

RÉSUMÉ

Interparietal inguinal hernia, an exceedingly rare type of inguinal hernia in which the hernia sac anatomically lies between the tissue layers of the abdominal wall, is difficult to diagnose from physical findings. Given the few reports on interparietal inguinal hernias, this condition has remained fairly unrecognized. Herein, we report the successful imaging and laparoscopic diagnoses as well as repair of an interparietal inguinal hernia. Atypical physical findings and computed tomography data help in the diagnosis of an interparietal inguinal hernia. The laparoscopic approach is useful and feasible for both the diagnosis and treatment of interparietal inguinal hernia.

11.
World J Surg ; 47(5): 1292-1302, 2023 05.
Article de Anglais | MEDLINE | ID: mdl-36688931

RÉSUMÉ

BACKGROUND: Although extended lymph node dissection during colon cancer surgery is recommended in both Western and Eastern countries, the perception and clinical significance of main lymph node metastasis (MLNM) remains controversial. METHODS: In total, 1557 patients with colon cancer who underwent curative resection with D3 dissection were retrospectively analyzed. Clinicopathological factors associated with MLNM were analyzed. Kaplan-Meier survival analysis and log-rank tests were used to compare the prognosis between the MLNM and non-MLNM groups. RESULTS: Multivariate analysis showed that overall survival (OS) [hazard ratio, 2.117 (0.939-4.774), p = 0.071] and recurrence-free survival (RFS) [hazard ratio, 2.183 (1.182-4.031), p = 0.013] were affected by the MLNM status independent of the TNM stage. Survival analysis demonstrated that among patients with stage III disease, the OS and RFS rates were significantly different between patients with and without MLNM (OS: p = 0.0147, RFS: p = 0.0001). However, the OS and RFS rates were not significantly different between patients who had stage III disease with MLNM and patients who had stage IV disease (OS: p = 0.5901, RFS: p = 0.9610). CONCLUSIONS: MLNM is an independent prognostic factor for patients with colon cancer. The addition of the MLNM status to the current TNM classification may enhance the prognostic value of the TNM staging system and the clinical efficacy of adjuvant therapy in patients with colon cancer.


Sujet(s)
Tumeurs du côlon , Humains , Pronostic , Métastase lymphatique/anatomopathologie , Études rétrospectives , Tumeurs du côlon/chirurgie , Tumeurs du côlon/anatomopathologie , Lymphadénectomie , Stadification tumorale , Noeuds lymphatiques/chirurgie , Noeuds lymphatiques/anatomopathologie
12.
Br J Ophthalmol ; 107(7): 920-926, 2023 Jul.
Article de Anglais | MEDLINE | ID: mdl-35301217

RÉSUMÉ

AIMS: To examine whether long-term corneal astigmatic changes after stabilisation of surgically induced astigmatism (SIA) following cataract surgery differ among eyes having against-the-rule (ATR), with-the-rule (WTR), and oblique astigmatism. METHODS: Anterior corneal astigmatism of 390 eyes in 390 patients (130 eyes each having ATR, WTR and oblique astigmatism) who underwent phacoemulsification with a horizontal clear corneal or scleral incision and 390 eyes in 390 control patients without surgery were examined using an auto-keratometer on the day that SIA stabilised (baseline) and at ≥8 years post baseline. Changes in corneal astigmatism during the ≥8 years post baseline were decomposed to vertical/horizontal (Rx) and oblique astigmatism components (Ry), and compared among baseline types of astigmatism and between eyes with and without surgery. RESULTS: The mean corneal astigmatic changes (Rx and Ry) showed an ATR shift of 0.2-0.3 D during the ≥8 years post baseline, which did not differ significantly among the ATR, WTR and oblique astigmatism groups in eyes with and without surgery. In the ATR, WTR and oblique groups, the mean Rx and Ry did not differ significantly between eyes with and without surgery. Double angle plots revealed an equivalent degree of ATR change in the ATR, WTR and oblique groups between eyes with and without surgery. CONCLUSION: Long-term corneal astigmatic changes towards ATR astigmatism occurred to a similar extent in eyes having ATR, WTR, oblique astigmatism and were comparable between eyes with and without surgery, suggesting that astigmatism type need not be considered when planning astigmatism correction.


Sujet(s)
Astigmatisme , Extraction de cataracte , Cataracte , Maladies de la cornée , Phacoémulsification , Humains , Astigmatisme/étiologie , Astigmatisme/chirurgie , Études rétrospectives , Cornée/chirurgie , Maladies de la cornée/chirurgie , Cataracte/complications , Topographie cornéenne
13.
J Cataract Refract Surg ; 48(7): 844-849, 2022 07 01.
Article de Anglais | MEDLINE | ID: mdl-35537866

RÉSUMÉ

PURPOSE: To determine morphological changes in the lens capsule with aging. SETTING: Hayashi Eye Hospital, Fukuoka, Japan. DESIGN: Cross-sectional study. METHODS: 25 eyes from the older patient group (aged 80 years or older) and 25 eyes from the younger patient group (aged 65 years or younger) who were diagnosed with cataract and indicated for surgery were included in the study. After continuous curvilinear capsulorhexis, the anterior lens capsule was collected, immediately fixed, and processed for electron microscopy analysis. Backscattered electron images of the cross-section of the anterior lens capsule were observed under a scanning electron microscope. The ultrastructure of the anterior lens capsule was observed and compared between the groups. Factors associated with the occurrence of the lamellar structure were also identified, with the presence or absence of a lamellar structure as an objective variable and preoperative clinical characteristics as the explanatory variables. RESULTS: 50 eyes of 50 patients were included. In the younger patient group, 20 eyes (80%) had a homogeneous lens capsule, whereas 5 eyes had lamellar structures. By contrast, in the older patient group, 5 eyes had homogeneous structures, while the remaining 20 eyes (80%) had lamellar structures. 1 eye showed capsular delamination. The only significant factor for the occurrence of lamellar structures was age group ( P < .01, nominal logistic regression analysis). CONCLUSIONS: Lamellar structures appear in the anterior capsule during aging. The appearance of lamellar structures indicates fragility of the lens capsule, which may, in turn, lead to capsular delamination or lens dislocation in some cases.


Sujet(s)
Capsule antérieure du cristallin , Cataracte , Capsule du cristallin , Capsule antérieure du cristallin/anatomopathologie , Capsulorhexis/méthodes , Cataracte/complications , Études transversales , Humains , Capsule du cristallin/chirurgie
14.
Int J Surg ; 101: 106631, 2022 May.
Article de Anglais | MEDLINE | ID: mdl-35447361

RÉSUMÉ

OBJECTIVE: To evaluate the prognostic value of the comprehensive risk score (CRS) of the Estimation of Physiologic Ability and Surgical Stress for managing patients with colorectal cancer (CRC) who underwent elective and emergency colorectal cancer surgery with curative intent. SUMMARY BACKGROUND DATA: CRS, which is calculated based on both clinical and surgical factors, is a good predictor of postoperative complications and mortality. However, the impact of CRS in CRC prognosis remains unclear. METHODS: Patients with CRC who underwent curative resection between 2010 and 2019 were retrospectively enrolled in this study. The cohort was divided into the low and high CRS groups. The prognostic value of CRS was evaluated via Cox regression and Kaplan-Meier analyses. The CRS cutoff value was obtained using the Youden index applied to OS curves and have not been validated by any validation cohorts. RESULTS: In total, 2407 patients, including 1359 and 1048 patients with low and high CRS, respectively, were enrolled in this study. Multivariate analysis revealed that a CRS was an independent prognostic factor of overall and recurrence-free survival regardless of disease stage. Furthermore, adjuvant chemotherapy was beneficial for the survival of patients with stage III CRC in both high and low CRS groups; however, the survival benefit was limited in elderly high CRS patients. CONCLUSIONS: CRS was a strong prognostic factor for CRC regardless of disease stage and might be considered as a biomarker for selecting elderly patients who are eligible for adjuvant chemotherapy.


Sujet(s)
Tumeurs colorectales , Sujet âgé , Traitement médicamenteux adjuvant , Humains , Pronostic , Études rétrospectives , Facteurs de risque
15.
Front Mol Biosci ; 9: 811548, 2022.
Article de Anglais | MEDLINE | ID: mdl-35445080

RÉSUMÉ

RNA ligases play important roles in repairing and circularizing RNAs post-transcriptionally. In this study, we generated an allelic knockout of ATP-dependent RNA ligase (Rnl) in the hyperthermophilic archaeon Thermococcus kodakarensis to identify its biological targets. A comparative analysis of circular RNA reveals that the Rnl-knockout strain represses circularization of C/D box sRNAs without affecting the circularization of tRNA and rRNA processing intermediates. Recombinant archaeal Rnl could circularize C/D box sRNAs with a mutation in the conserved C/D box sequence element but not when the terminal stem structures were disrupted, suggesting that proximity of the two ends could be critical for intramolecular ligation. Furthermore, T. kodakarensis accumulates aberrant RNA fragments derived from ribosomal RNA in the absence of Rnl. These results suggest that Rnl is responsible for C/D box sRNA circularization and may also play a role in ribosomal RNA processing.

16.
Int J Mol Sci ; 23(7)2022 Apr 06.
Article de Anglais | MEDLINE | ID: mdl-35409407

RÉSUMÉ

The Saccharomyces cerevisiae Trm11 and Trm112 complex (Trm11-Trm112) methylates the 2-amino group of guanosine at position 10 in tRNA and forms N2-methylguanosine. To determine the elements required in tRNA for methylation by Trm11-Trm112, we prepared 60 tRNA transcript variants and tested them for methylation by Trm11-Trm112. The results show that the precursor tRNA is not a substrate for Trm11-Trm112. Furthermore, the CCA terminus is essential for methylation by Trm11-Trm112, and Trm11-Trm112 also only methylates tRNAs with a regular-size variable region. In addition, the G10-C25 base pair is required for methylation by Trm11-Trm112. The data also demonstrated that Trm11-Trm112 recognizes the anticodon-loop and that U38 in tRNAAla acts negatively in terms of methylation. Likewise, the U32-A38 base pair in tRNACys negatively affects methylation. The only exception in our in vitro study was tRNAValAAC1. Our experiments showed that the tRNAValAAC1 transcript was slowly methylated by Trm11-Trm112. However, position 10 in this tRNA was reported to be unmodified G. We purified tRNAValAAC1 from wild-type and trm11 gene deletion strains and confirmed that a portion of tRNAValAAC1 is methylated by Trm11-Trm112 in S. cerevisiae. Thus, our study explains the m2G10 modification pattern of all S. cerevisiae class I tRNAs and elucidates the Trm11-Trm112 binding sites.


Sujet(s)
Methyltransferases , Protéines de Saccharomyces cerevisiae , Guanine/métabolisme , Méthylation , Methyltransferases/métabolisme , Conformation d'acide nucléique , ARN de transfert/génétique , ARN de transfert/métabolisme , ARN de transfert de la valine/métabolisme , Saccharomyces cerevisiae/génétique , Saccharomyces cerevisiae/métabolisme , Protéines de Saccharomyces cerevisiae/génétique , Protéines de Saccharomyces cerevisiae/métabolisme , T-RNA methyltransferases/génétique , T-RNA methyltransferases/métabolisme
17.
Jpn J Ophthalmol ; 66(2): 167-172, 2022 Mar.
Article de Anglais | MEDLINE | ID: mdl-35122563

RÉSUMÉ

PURPOSE: To compare the progression of posterior vitreous detachment (PVD) after cataract surgery in eyes with high myopia with that in eyes without high myopia. STUDY DESIGN: Prospective observational study. METHODS: Eighty eyes of 80 patients with high myopia and 160 eyes of 160 patients without high myopia scheduled for phacoemulsification were recruited. PVD status was examined using swept-source optical coherence tomography at 2 days postoperatively (baseline) and at 3, 6, and 12 months postbaseline and classified into 5 stages: 0 (no PVD), 1 (paramacular PVD), 2 (perifoveal PVD), 3 (peripapillary PVD), and 4 (complete PVD). The PVD stage and incidence of progression to complete PVD of the 2 groups were compared. RESULTS: The mean PVD stage did not differ significantly between the groups at baseline or at 3 months postbaseline but was significantly more progressed in the high myopia group than in the nonhigh myopia group at 6 months and 12 months postbaseline (P ≤ 0.0201). The Kaplan-Meier survival rate for complete PVD was significantly lower in the high myopia group (P = 0.0129). After adjusting for age, sex, and baseline PVD stage, the hazard ratio for complete PVD was 1.68-fold higher in the high myopia group than in the nonhigh myopia group (P = 0.0326, 95% CI 1.04-2.70). CONCLUSION: After cataract surgery, PVD progressed significantly faster in eyes with high myopia than in eyes without high myopia, and the relative risk for complete PVD was 1.68-fold higher in eyes with high myopia, suggesting that highly myopic eyes are at considerably high risk for retinal disease postoperatively.


Sujet(s)
Cataracte , Myopie , Décollement du vitré , Cataracte/complications , Humains , Myopie/complications , Tomographie par cohérence optique/méthodes , Corps vitré , Décollement du vitré/diagnostic , Décollement du vitré/étiologie , Décollement du vitré/chirurgie
18.
Graefes Arch Clin Exp Ophthalmol ; 260(2): 509-519, 2022 Feb.
Article de Anglais | MEDLINE | ID: mdl-34495370

RÉSUMÉ

PURPOSE: To examine the long-term changes in the astigmatism-correcting effect of a toric intraocular lens (IOL) after stabilization of surgically induced astigmatic changes due to cataract surgery. METHODS: Unilateral eyes of 120 patients that received a toric IOL for against-the-rule (ATR) or with-the-rule (WTR) astigmatism were enrolled. Manifest refractive and anterior corneal astigmatism, and ocular residual astigmatism which is mainly derived from internal optics were examined preoperatively, at approximately 2 months postoperatively (baseline) and at 5 ~ 10 years postbaseline. The astigmatism was decomposed to vertical/horizontal (Rx) and oblique components (Ry), which was compared between baseline and 5 ~ 10 years postbaseline. RESULTS: In the eyes having ATR astigmatism, the mean Rx and Ry of the manifest refractive and corneal astigmatism significantly changed toward ATR astigmatism between the baseline and 5 ~ 10 years postbaseline (p ≤ 0.0304), but those of ocular residual astigmatism did not change significantly between the 2 time points. In the eyes having WTR astigmatism, the Rx and Ry of refractive, corneal, and ocular residual astigmatism did not change significantly between the 2 time points. Double-angle plots revealed an ATR shift in refractive and corneal astigmatism and no marked change in the ocular residual astigmatism in the eyes with ATR astigmatism, and there is no change in this astigmatism in the eyes with WTR astigmatism. CONCLUSION: The long-term changes with age in the effect of a toric IOL significantly deteriorated due to an ATR shift of corneal astigmatism in the eyes having ATR astigmatism, while it was maintained in eyes having WTR astigmatism, suggesting that ATR astigmatism should be overcorrected.


Sujet(s)
Astigmatisme , Lentilles intraoculaires , Phacoémulsification , Astigmatisme/étiologie , Astigmatisme/chirurgie , Cornée/chirurgie , Humains , Pose d'implant intraoculaire , Réfraction oculaire
19.
Sci Rep ; 11(1): 20035, 2021 10 08.
Article de Anglais | MEDLINE | ID: mdl-34625615

RÉSUMÉ

We investigated the postoperative visual outcomes and morphological changes of the internal limiting membrane (ILM) flap, in patients who underwent the temporal inverted ILM flap technique for macular hole (MH). Between August 2018 and February 2020, 22 eyes of 22 patients with idiopathic or myopic MH who underwent vitrectomy with ILM flap were included in this study and followed-up for more than 6 months. Postoperative MH status, comparison of best-corrected visual acuity (BCVA) before and 6 months after surgery, changes in the ILM flap area at 1 and 6 months postoperatively, and the factors related to changes in ILM flap size, were analyzed. MH closure was achieved in all of the patients. The BCVA at 6 months postoperatively (0.18 ± 0.15) was significantly better than the preoperative BCVA of 0.63 ± 0.37 (P < 0.001, paired t test). The area of the ILM flap decreased significantly from 3.25 ± 1.27 mm2 at 1 month to 3.13 ± 1.23 mm2 at 6 months (P = 0.024, Wilcoxon signed-rank test). Two eyes showed an ILM flap contraction of more than 20%, and one eye required reoperation due to an increase in metamorphopsia and decreased visual acuity. Among age, sex, ILM flap area at 1 month, preoperative BCVA, and axial length, ILM flap contraction was correlated with patient age and ILM flap area. Although vitrectomy with the inverted ILM flap technique confers a good visual outcome, the ILM flap may contract in younger patients.


Sujet(s)
Membrane basale/anatomopathologie , Membrane épirétinienne/anatomopathologie , Myopie/complications , Décollement de la rétine/chirurgie , Perforations de la rétine/chirurgie , Lambeaux chirurgicaux/anatomopathologie , Vitrectomie/effets indésirables , Sujet âgé , Membrane basale/chirurgie , Membrane épirétinienne/chirurgie , Femelle , Humains , Mâle , Adulte d'âge moyen , Études prospectives , Réintervention , Décollement de la rétine/étiologie , Décollement de la rétine/anatomopathologie , Perforations de la rétine/étiologie , Perforations de la rétine/anatomopathologie , Lambeaux chirurgicaux/chirurgie , Acuité visuelle
20.
World J Clin Cases ; 9(12): 2801-2810, 2021 Apr 26.
Article de Anglais | MEDLINE | ID: mdl-33969062

RÉSUMÉ

BACKGROUND: Definitive chemoradiotherapy (dCRT) using cisplatin plus 5fluorouracil (CF) with radiation is considered the standard treatment for unresectable locally advanced T4 esophageal squamous cell carcinoma (ESCC). Recently, induction chemotherapy has received attention as an effective treatment strategy. CASE SUMMARY: We report a successful case of a 59-year-old female with unresectable locally advanced T4 ESCC treated by two additional courses of chemotherapy with CF after induction chemotherapy with docetaxel, cisplatin and fluorouracil (DCF) followed by dCRT. Initial esophagogastroduodenoscopy (EGD) detected a type 2 advanced lesion located on the middle part of the esophagus, with stenosis. Computed tomography detected the primary tumor with suspected invasion of the left bronchus and 90° of direct contact with the aorta, and upper mediastinal lymph node metastasis. Pathological findings from biopsy revealed squamous cell carcinoma. We initially performed induction chemotherapy using three courses of DCF, but the lesion was still evaluated unresectable after DCF chemotherapy. Therefore, we subsequently performed dCRT treatment (CF and radiation). After dCRT, prominent reduction of the primary tumor was recognized but a residual tumor with ulceration was detected by EGD. Since the patient had some surgical risk, we performed two additional courses of CF and achieved a clinically complete response. After 14 mo from last administration of CF chemotherapy, recurrence has not been detected by computed tomography and EGD, and biopsy from the scar formation has revealed no cancer cells. CONCLUSION: We report successful case with tumor remnants even after DCF and subsequent dCRT, for whom a complete response was finally achieved with two additional courses of CF chemotherapy. Additional CF chemotherapy could be one radical treatment option for residual ESCC after treatment with induction DCF followed by dCRT to avoid salvage surgery, especially for high-risk patients.

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