ABSTRACT
COVID-19 has a range of complications, from no symptoms to severe pneumonia. It can also affect multiple organs including the nervous system. COVID-19 affects the brain, leading to neurological symptoms such as delirium. Delirium, a sudden change in consciousness, can increase the risk of death and prolong the hospital stay. However, research on delirium prediction in patients with COVID-19 is insufficient. This study aimed to identify new risk factors that could predict the onset of delirium in patients with COVID-19 using machine learning (ML) applied to nursing records. This retrospective cohort study used natural language processing and ML to develop a model for classifying the nursing records of patients with delirium. We extracted the features of each word from the model and grouped similar words. To evaluate the usefulness of word groups in predicting the occurrence of delirium in patients with COVID-19, we analyzed the temporal changes in the frequency of occurrence of these word groups before and after the onset of delirium. Moreover, the sensitivity, specificity, and odds ratios were calculated. We identified (1) elimination-related behaviors and conditions and (2) abnormal patient behavior and conditions as risk factors for delirium. Group 1 had the highest sensitivity (0.603), whereas group 2 had the highest specificity and odds ratio (0.938 and 6.903, respectively). These results suggest that these parameters may be useful in predicting delirium in these patients. The risk factors for COVID-19-associated delirium identified in this study were more specific but less sensitive than the ICDSC (Intensive Care Delirium Screening Checklist) and CAM-ICU (Confusion Assessment Method for the Intensive Care Unit). However, they are superior to the ICDSC and CAM-ICU because they can predict delirium without medical staff and at no cost.
Subject(s)
COVID-19 , Delirium , Humans , Delirium/diagnosis , Delirium/epidemiology , Delirium/etiology , Nursing Records , Retrospective Studies , COVID-19/complications , COVID-19/epidemiology , Intensive Care Units , Critical Care/methodsABSTRACT
Genome-editing tools such as the clustered regularly interspaced short palindromic repeats/Cas9 (CRISPR/Cas9) system have become essential tools for increasing the efficiency and accuracy of plant breeding. Using such genome-editing tools on maize, one of the most important cereal crops of the world, will greatly benefit the agriculture and the mankind. Conventional genome-editing methods typically used for maize involve insertion of a Cas9-guide RNA expression cassette and a selectable marker in the genome DNA; however, using such methods, it is essential to eliminate the inserted DNA cassettes to avoid legislative concerns on gene-modified organisms. Another major hurdle for establishing an efficient and broadly applicable DNA-free genome-editing system for maize is presented by recalcitrant genotypes/cultivars, since cell/tissue culture and its subsequent regeneration into plantlets are crucial for producing transgenic and/or genome-edited maize. In this study, to establish a DNA-free genome-editing system for recalcitrant maize genotypes/cultivars, Cas9-gRNA ribonucleoproteins were directly delivered into zygotes isolated from the pollinated flowers of the maize-B73 cultivar. The zygotes successfully developed and were regenerated into genome-edited plantlets by co-culture with phytosulfokine, a peptide phytohormone. The method developed herein made it possible to obtain DNA- and selectable-marker-free genome-edited recalcitrant maize genotypes/cultivars with high efficiency. This method can advance the molecular breeding of maize and other important cereals, regardless of their recalcitrant characteristics.
Subject(s)
CRISPR-Cas Systems , Gene Editing , Genome, Plant , Zea mays , Zea mays/genetics , Gene Editing/methods , Plants, Genetically Modified , Zygote/metabolism , Plant Breeding/methods , RNA, Guide, CRISPR-Cas Systems/genetics , DNA, Plant/geneticsABSTRACT
Somaclonal variation was studied by whole-genome sequencing in rice plants (Oryza sativa L., 'Nipponbare') regenerated from the zygotes, mature embryos, and immature embryos of a single mother plant. The mother plant and its seed-propagated progeny were also sequenced. A total of 338 variants of the mother plant sequence were detected in the progeny, and mean values ranged from 9.0 of the seed-propagated plants to 37.4 of regenerants from mature embryos. The natural mutation rate of 1.2 × 10-8 calculated using the variants in the seed-propagated plants was consistent with the values reported previously. The ratio of single nucleotide variants (SNVs) among the variants in the seed-propagated plants was 91.1%, which is higher than 56.1% previously reported, and not significantly different from those in the regenerants. Overall, the ratio of transitions to transversions of SNVs was lower in the regenerants as shown previously. Plants regenerated from mature embryos had significantly more variants than different progeny types. Therefore, using zygotes and immature embryos can reduce somaclonal variation during the genetic manipulation of rice.
ABSTRACT
Background: To determine the effectiveness of baricitinib in patients with coronavirus disease 2019 (COVID-19), investigate whether baricitinib prevents the need for invasive mechanical ventilation and identify patient subgroups that would benefit from baricitinib. Methods: This observational matched-cohort study was conducted by the Japan COVID-19 Task Force, a nationwide multicenter consortium. Patients with COVID-19 aged ≥18 years were identified from 70 hospitals in Japan. Among patients with confirmed COVID-19 from February 2020 to September 2021, those receiving baricitinib were propensity-score matched with controls. Results: Among 3309 patients, 144 propensity score-matched pairs were identified. Thirteen (9.0%) patients in the baricitinib group and 27 (18.8%) in the control group required invasive mechanical ventilation during the disease course (odds ratio, 0.43). Although the baricitinib group had more severe disease, there were no significant differences in the intensive care unit admission rates (odds ratio, 1.16) and mortality rates (odds ratio, 0.74) between groups. In subgroup analyses, baricitinib was associated with a significant reduction in the need for invasive mechanical ventilation in patients requiring oxygen support (odds ratio, 0.28), with rapid shadow spread on chest radiography (odds ratio, 0.11), or treated with remdesivir (odds ratio, 0.27), systemic corticosteroids (odds ratio, 0.31), or anticoagulants (odds ratio, 0.17). Conclusions: Baricitinib is effective at preventing the need for invasive mechanical ventilation in patients with COVID-19.
ABSTRACT
Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection.
Subject(s)
COVID-19 , Genome-Wide Association Study , COVID-19/epidemiology , COVID-19/genetics , Humans , Japan/epidemiology , Lectins, C-Type/genetics , Membrane Glycoproteins/genetics , Polymorphism, Single Nucleotide , Quantitative Trait Loci/genetics , Receptors, Immunologic/geneticsABSTRACT
In vitro fertilization (IVF) systems using isolated gametes have been used to dissect post-fertilization events in angiosperms, as female plant gametophytes are deeply embedded within the ovaries. In addition, hybrid and polyploid zygotes can be produced by using IVF systems. Complete IVF systems of maize and rice, two out of three major energy-providing crops, have been established in order to acquire detailed knowledge of mechanisms of fertilization and early embryogenesis. Following in the footsteps of previous success, a wheat IVF system was developed to introduce the advantages of this technology to wheat research. Fusion of gametes was performed via a modified electrofusion method, and the zygote formed a cell wall and two nucleoli. The zygotes divided into symmetric two-celled embryos, globular-like embryos and multicellular club-shaped embryos which are mostly consistent with those in the embryos in planta. IVF-produced club-shaped embryos developed into compact embryonic calli and subsequently regenerated into fertile plants. In this chapter, we provide a detailed description of wheat IVF system that might become an important technique for generating new genotypes of wheat and/or new hybrids as well as for investigating fertilization-induced events in wheat.
Subject(s)
Seeds , Triticum , Fertilization/genetics , Fertilization in Vitro , Germ Cells , Seeds/genetics , Triticum/genetics , ZygoteABSTRACT
BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is the current major modality for the diagnosis of sarcoidosis with hilar and mediastinal lymphadenopathy because of its higher diagnostic yield and safety; however, predictors for the pathological diagnosis of sarcoidosis by EBUS-TBNA remain uncertain. The objective of this study was to determine a novel predictor for the pathological diagnosis of sarcoidosis by EBUS-TBNA. METHODS: Patients with pathological and/or clinical diagnosis of sarcoidosis were identified from patients who underwent EBUS-TBNA between February 2010 and December 2017, retrospectively. We extracted data on age, sex, stage of disease, number of punctured lymph nodes, number of punctures per procedure and target lymph node, and size of punctured lymph node. Next, we divided patients into groups of pathological positive and negative by EBUS-TBNA, and multivariate logistic regression analysis was performed following univariate analyses to evaluate the efficacy of these parameters as a predictive factor of the pathological diagnosis of sarcoidosis by EBUS-TBNA. RESULTS: We selected 89 patients involving 115 mediastinal and hilar lymph nodes. The diagnostic yield of sarcoidosis by EBUS-TBNA was 74/89 (83.1%). There were no significant differences in the size of lymph node and number of punctures between the groups, there was a significant difference in age by univariate analyses. In addition, multivariate logistic regression revealed that age was significantly associated with pathological diagnosis of sarcoidosis by EBUS-TBNA [5 years = 1 unit, odds ratio (OR), 0.79; 95% CI, 0.64-0.97; P=0.03]. CONCLUSIONS: The diagnostic yield of sarcoidosis by EBUS-TBNA was higher in younger than older patients. Therefore, age may be a novel independent predictor for the pathological diagnosis of sarcoidosis by EBUS-TBNA.
ABSTRACT
Technology involving the targeted mutagenesis of plants using programmable nucleases has been developing rapidly and has enormous potential in next-generation plant breeding. Notably, the clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein-9 nuclease (Cas9) (CRISPR-Cas9) system has paved the way for the development of rapid and cost-effective procedures to create new mutant populations in plants1,2. Although genome-edited plants from multiple species have been produced successfully using a method in which a Cas9-guide RNA (gRNA) expression cassette and selectable marker are integrated into the genomic DNA by Agrobacterium tumefaciens-mediated transformation or particle bombardment3, CRISPR-Cas9 integration increases the chance of off-target modifications4, and foreign DNA sequences cause legislative concerns about genetically modified organisms5. Therefore, DNA-free genome editing has been developed, involving the delivery of preassembled Cas9-gRNA ribonucleoproteins (RNPs) into protoplasts derived from somatic tissues by polyethylene glycol-calcium (PEG-Ca2+)-mediated transfection in tobacco, Arabidopsis, lettuce, rice6, Petunia7, grapevine, apple8 and potato9, or into embryo cells by biolistic bombardment in maize10 and wheat11. However, the isolation and culture of protoplasts is not feasible in most plant species and the frequency of obtaining genome-edited plants through biolistic bombardment is relatively low. Here, we report a genome-editing system via direct delivery of Cas9-gRNA RNPs into plant zygotes. Cas9-gRNA RNPs were transfected into rice zygotes produced by in vitro fertilization of isolated gametes12 and the zygotes were cultured into mature plants in the absence of selection agents, resulting in the regeneration of rice plants with targeted mutations in around 14-64% of plants. This efficient plant-genome-editing system has enormous potential for the improvement of rice as well as other important crop species.
Subject(s)
DNA, Plant/genetics , Gene Editing/methods , Oryza/genetics , CRISPR-Associated Protein 9 , CRISPR-Cas Systems , Genetic Markers/genetics , Genome, Plant/genetics , ZygoteABSTRACT
In vitro fertilization (IVF) systems using isolated gametes have been utilized to dissect post-fertilization events in angiosperms, since the female gametophytes of plants are deeply embedded within ovaries. In addition, IVF systems have been used to produce hybrid and polyploid zygotes. Complete IVF systems have been established in maize and rice, two of three major crop species providing the majority of human energy intake. Among those crop species, gametes of wheat have not been used to establish a complete IVF system successfully. In this study, a wheat IVF system was developed to introduce the advantages of this technology to wheat research. Fusion of gametes was performed via a modified electrofusion method, and the fusion product, a zygote, formed a cell wall and two nucleoli. The first division of zygotes was observed 19-27 h after fusion, and the resulting two-celled embryo developed into 10-20-celled globular-like embryos and multicellular club-shaped embryos by 3 and 7-10 d after fusion, respectively. Such zygotic division profiles were mostly consistent with those in the embryo sac, suggesting that the division profile of IVF-produced early embryos reflects that of early embryos in planta. Although the IVF-produced club-shaped embryos did not develop into differentiated embryos but into compact embryonic calli, fertile plants could be regenerated from the embryonic calli, and the seeds harvested from those plants grew normally into seedlings. The IVF system described here might become an important technique for generating new genotypes of wheat and/or new hybrids as well as for investigating fertilization-induced events in wheat.
Subject(s)
Seeds/metabolism , Triticum/genetics , Fertilization in Vitro , Seeds/genetics , ZygoteABSTRACT
This report describes two patients with sporadic lymphangioleiomyomatosis complicated by protein-losing enteropathy (PLE). Imaging studies indicated retroperitoneal lymphangioleiomyomas and abnormalities of the adjacent digestive tract. Endoscopic mucosal biopsy revealed colonic lymphangiectasia in one patient; whereas the site in the other patient was intestinal. Treatment with sirolimus led to the complete resolution of PLE within several months; additionally, marked shrinkage was observed in the lymphangioleiomyomas of both cases. These findings suggest that colonic or intestinal lymphatic congestion due to neighboring lymphangioleiomyomas was the mechanism for the development of PLE. At the time of writing this report, the beneficial effect of sirolimus has lasted for more than 3 years.
Subject(s)
Intestinal Diseases/complications , Lymphangiectasis/complications , Lymphangioleiomyomatosis/complications , Protein-Losing Enteropathies/etiology , Adult , Colonic Diseases/complications , Diet Therapy/methods , Diet, Fat-Restricted , Female , Humans , Immunosuppressive Agents/therapeutic use , Protein-Losing Enteropathies/therapy , Sirolimus/therapeutic use , Treatment OutcomeABSTRACT
Polyethylene glycol calcium (PEG-Ca2+) transfection-mediated analysis allows rapid and efficient examination of gene function. To investigate the diverse cellular functions of genes of interest in plant cells, macromolecules, such as DNA, RNA, and proteins, are delivered into protoplasts prepared from somatic tissues or calli using a PEG-Ca2+ transfection procedure. To take advantage of this macromolecule delivery system in the reproductive and developmental biology of angiosperms, this study established a PEG-Ca2+ transfection system with isolated egg cells and zygotes. The conditions for PEG and plasmid DNA concentrations for transfection of rice egg cells were first addressed, and ~30% of PEG-Ca2+-transfected egg cells showed exogenous and transient expressions of fluorescent proteins from plasmid DNA delivered into the cells. Interestingly, a dual expression of two different fluorescent proteins in the same egg cell using two kinds of plasmid DNAs was also observed. For PEG-Ca2+ transfection with maize zygotes, ~80% of zygotes showed expression of GFP proteins from plasmid DNA. Importantly, PEG-transfected zygotes developed normally into cell masses and mature plants. These results suggest that the present PEG-Ca2+-mediated transient expression system provides a novel and effective platform for expressing and analyzing genes of interest in egg cells and zygotes. Moreover, combined with the CRISPR/Cas9 approach, the present transient expression system in zygotes will become a powerful and alternative tool for the preparation of gene-edited plants.
ABSTRACT
BACKGROUND: Poor exercise tolerability is a major barrier to improving the quality of life of patients with chronic obstructive pulmonary disease (COPD). Although COPD is often treated with long-acting ß2 adrenergic agonists, few studies have examined their effects on exercise tolerability. METHODS: In this study, Japanese COPD patients were treated with 2 mg transdermal tulobuterol, a long-acting ß2 agonist, once daily for 4 weeks. Spirometry and exercise tests were conducted at baseline and at the end of treatment. The patients conducted constant load (30 W for 5 min) and incremental load (starting at 10 W and increasing by 10 W every 1 min for 5 min to a maximum load of 50 W) exercise tests on a cycle ergometer. RESULTS: Thirteen patients with stable COPD participated in this study (mean age ± standard deviation (SD), 69.5±9.7 years; smoking history 55.9±27.8 pack-years). Resting spirometric parameters were unchanged at the end of treatment. The maximum Borg scale for dyspnea and the Borg scale slope (BSS) decreased significantly from baseline to the end of treatment. The threshold load of dyspnea (TLD) increased slightly, although not significantly, in the constant load test but not in the incremental load test. There were no changes in respiratory parameters during exercise after treatment. CONCLUSIONS: In conclusion, we found that treatment with transdermal tulobuterol for 4 weeks improved self-assessed dyspnea in Japanese COPD patients during constant and incremental exercise tests. This improvement in dyspnea may encourage patients to perform daily life activities or regular physical activity.
ABSTRACT
BACKGROUND: We see patients who present with spirometry airflow limitation despite their forced expiratory volume in one second (FEV1) as well as forced vital capacity (FVC) to be supernormal (FEV1/FVC < 70%, both the %FEV1 and the %FVC ⧠100%) in asymptomatic healthy non-smokers. Based on previous studies, we hypothesized these spirometry conditions (results measured with spirometry) could be suitably used as a practical surrogate marker of pulmonary dysanapsis: the condition of disproportionate but physiologically normal growth between airways and lung parenchyma. METHODS: We compared the conventional surrogate marker of dysanapsis, maximum mid-expiratory flow to FVC (MMF/FVC), in SUBJECTS (FEV1/FVC < 70%, both the %FEV1 and the %FVC ⧠100% in healthy non-smokers) (n = 25), in EMPHYSEMA (CT confirmed pulmonary emphysema, same spirometry results with SUBJECTS) (n = 55), and in CONTROLS (age- and height- matched, normal spirometry results) (n = 25). Next we added imaging analysis to evaluate the relationship between the cross sectional airway luminal area (X-Ai) and the lung volume results among the three groups. RESULTS: The MMF/FVC was significantly lower in SUBJECTS and in EMPHYSEMA compared to CONTROLS. However, percent predicted peak expiratory flow (%PEFR) was significantly lower only in SUBJECTS and not in EMPHYSEMA compared to CONTROLS. The ratio of the X-Ai of the trachea and right apical bronchus to lung volume was significantly lower in SUBJECTS compared to CONTROLS. CONCLUSION: The simple spirometry conditions in SUBJECTS are highly suggestive of practical surrogate marker of pulmonary dysanapsis. Awareness of this concept would help to attenuate the risk of overdiagnosis of obstructive pulmonary disease.
Subject(s)
Lung Diseases, Obstructive/diagnosis , Lung Diseases, Obstructive/physiopathology , Spirometry , Aged , Asymptomatic Diseases , Case-Control Studies , Female , Forced Expiratory Volume , Humans , Male , Pulmonary Emphysema/epidemiology , Retrospective Studies , Vital CapacityABSTRACT
BACKGROUND: Pulmonary rehabilitation has generally relieved symptoms, strengthened exercise endurance and improved health-related quality of life (QOL) in patients with COPD, but recovery of pulmonary function remains questionable. This analysis of our innovative rehabilitation program is directed at documenting changes in patients' expiratory airflow limitation, pulmonary symptoms and QOL. This program is designed to provide "respiratory conditioning", a physical therapist-assisted intensive flexibility training that focuses on stretching and rib cage mobilization. METHODS: Thirty-one patients with COPD who attended rehabilitation sessions at Juntendo University Hospital from 1999 to 2006 were analyzed. Pulmonary function, expiratory flow limitation during tidal breathing, six minute walk distance (6MWD), respiratory muscle strength, and St. George Respiratory Questionnaire (SGRQ) were measured before and after pulmonary rehabilitation. RESULTS: In participants ages 68±7 years, the FEV(1)% predicted was 39.3±15.7%. 6MWD, SGRQ and respiratory muscle strength were significantly improved after pulmonary rehabilitation. Although neither FEV(1)% predicted nor FEV(1)/FVC was affected to a significant extent, indicating little effect on airflow limitation, expiratory flow limitation in supine as well as seated during tidal breathing improved significantly. Moreover, rehabilitation significantly diminished TLC% predicted, FRC% predicted, RV% predicted and RV/TLC values, thus indicating a reduction of hyperinflation of the lungs at rest. CONCLUSIONS: The present results suggest that our rehabilitation program with respiratory conditioning significantly lowered the hyperinflation of lungs at rest as well as the expiratory flow limitation during tidal breathing. In patients with COPD, overall pulmonary function improved, exercise endurance increased and health-related QOL was enhanced.
ABSTRACT
AIMS: The purpose of this study was to determine the factors that adversely affect the weaning of elderly patients with community-acquired pneumonia from mechanical ventilation. METHODS: This study retrospectively investigated the medical records of 71 elderly patients (65 years or older) who were admitted to the hospital because of community-acquired pneumonia and required mechanical ventilation between January 2003 and December 2007. The patients were divided into two groups: group A, which included 33 patients who were successfully weaned from mechanical ventilation, and group B, which included 38 patients who could not be weaned from mechanical ventilation. The study compared the patients' background, vital signs, and laboratory and bacteriological examinations at the beginning of mechanical ventilation. A multiple logistic regression analysis was performed to identify the factors associated with difficulties in weaning patients from mechanical ventilation. RESULTS: In group B, there were significantly more smokers (P < 0.05) and more patients with emphysematous changes on thoracic CT (P < 0.05). In group A, the concentrations of total serum protein (P < 0.05) and albumin (P < 0.05) were significantly higher. A multiple logistic regression analysis revealed that patients with community-acquired pneumonia who showed emphysematous changes on thoracic CT (OR = 4.92, 95%CI 1.08-22.46) and/or a low concentration of serum albumin <3.0 g/dL (OR = 4.25, 95%CI 1.17-15.45) had difficulty being weaned from mechanical ventilation. CONCLUSION: Our study suggests that elderly patients with community-acquired pneumonia with emphysematous changes on thoracic CT and/or a low concentration of serum albumin level have difficulty being weaned from mechanical ventilation.
Subject(s)
Pneumonia, Bacterial/therapy , Respiration, Artificial , Ventilator Weaning , Aged , Community-Acquired Infections/therapy , Female , Humans , Male , Retrospective StudiesSubject(s)
Fluorine Radioisotopes , Fluorodeoxyglucose F18 , Positron-Emission Tomography , Radiopharmaceuticals , Solitary Pulmonary Nodule/diagnostic imaging , Tuberculoma/diagnostic imaging , Tuberculosis, Pulmonary/diagnostic imaging , Biopsy , Humans , Solitary Pulmonary Nodule/microbiology , Staining and Labeling , Thoracic Surgery, Video-Assisted , Tuberculoma/diagnosis , Tuberculoma/pathology , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/pathologyABSTRACT
A 26-year-old-woman was given a diagnosis of Wegener's granulomatosis and began treatment by both prednisolone and cyclophosphamide at another institution. She was then admitted to our hospital due to progressive multiple pulmonary nodules. A diagnosis of pulmonary metastases from bladder cancer was established with radiological and histological examinations obtained by transbronchial lung biopsy (TBLB) and transurethral resection of the bladder tumor (TUR-Bt). She had already received a total dose of 120 g of cyclophosphamide, which could be related to the development of bladder cancer. On detecting multiple pulmonary nodules in patients with Wegener's granulomatosis treated with cyclophosphamide, it is necessary to consider the possibility of pulmonary metastases form urinary bladder cancer.
Subject(s)
Carcinoma, Transitional Cell/pathology , Granulomatosis with Polyangiitis/diagnosis , Lung Neoplasms/secondary , Urinary Bladder Neoplasms/pathology , Adult , Carcinoma, Transitional Cell/chemically induced , Cyclophosphamide/adverse effects , Diagnosis, Differential , Female , Granulomatosis with Polyangiitis/drug therapy , Humans , Recurrence , Urinary Bladder Neoplasms/chemically inducedABSTRACT
A 53-year-old woman was admitted to our hospital due to a severe respiratory condition and malnutrition. Radiological and electrophysiological findings suggested the existence of inexplicable cor pulmonale. Although we commenced to determine the causes of her severe condition, she suddenly died 3 days after admission. Postmortem autopsy revealed tumor cell microemboli in the small pulmonary arteries due to gastric cancer. Such a case of cor pulmonale as the first clinical manifestation is exceptionally rare. Occult malignancy should be considered as a differential diagnosis when one encounters a patient with subacutely aggravated respiratory condition and inexplicable cor pulmonale.
Subject(s)
Lung Neoplasms/complications , Pulmonary Embolism/complications , Pulmonary Embolism/etiology , Pulmonary Heart Disease/diagnosis , Pulmonary Heart Disease/etiology , Stomach Neoplasms/complications , Diagnosis, Differential , Fatal Outcome , Female , Humans , Middle Aged , Pulmonary Artery/pathologyABSTRACT
Sialyltransferases are a family of glycosyltransferases that catalyze the transfer of N-acetylneuraminic acid residues from cytidine monophosphate N-acetylneuraminic acid (CMP-NeuAc) as a donor substrate to the carbohydrate groups of glycoproteins and glycolipids as acceptor substrates. We determined the crystal structure of Delta16psp26ST, the N-terminal truncated form of alpha2,6-sialyltransferase from Vibrionaceae Photobacterium sp. JT-ISH-224, complexed with a donor product CMP and an acceptor substrate lactose. Delta16psp26ST has three structural domains. Domain 1 belongs to the immunoglobulin-like beta-sandwich fold, and domains 2 and 3 form the glycosyltransferase-B structure. The CMP and lactose were bound in the deep cleft between domains 2 and 3. In the structure, only Asp232 was within hydrogen-binding distance of the acceptor O6 carbon of the galactose residue in lactose, and His405 was within hydrogen-binding distance of the phosphate oxygen of CMP. Mutation of these residues greatly decreased the activity of the enzyme. These structural and mutational results indicated that Asp232 might act as a catalytic base for deprotonation of the acceptor substrate, and His405 might act as a catalytic acid for protonation of the donor substrate. These findings are consistent with an in-line-displacement reaction mechanism in which Delta16psp26ST catalyzes the inverting transfer reaction. Unlike the case with multifunctional sialyltransferase (Delta24PmST1) complexed with CMP and lactose, the crystal structure of which was recently reported, the alpha2,6 reaction specificity of Delta16psp26ST is likely to be determined by His123.
Subject(s)
Bacterial Proteins/chemistry , Cytidine Monophosphate/chemistry , Lactose/chemistry , Photobacterium/enzymology , Sialyltransferases/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Binding Sites , Catalysis , Crystallography, X-Ray , Cytidine Monophosphate/metabolism , Glycerol/metabolism , Lactose/metabolism , Models, Molecular , Photobacterium/classification , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sialyltransferases/genetics , Sialyltransferases/metabolism , Substrate Specificity , beta-D-Galactoside alpha 2-6-SialyltransferaseABSTRACT
Sialyltransferases are key enzymes for the biosynthesis of sialyl-glycoproteins and sialyl-lipids and the genes encoding sialyltransferases have been cloned from mammalian and bacterial source. In the mammalian sialyltransferase, existence of three conserved regions, named sialyl motifs, has been demonstrated. On the other hand, two short motifs, named D/E-D/E-G motif and HP motif, have been reported in the bacterial sialyltransferases very recently. From the results of multiple alignments among the sialyltransferases belonging to Glycosyltransferase family 80 and crystal structures of two reported sialyltransferases, it is clearly demonstrated that the third conserved-functional motif exists in the bacterial sialyltransferases that have been classified into Glycosyltransferase family 80 in this study.