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1.
Mod Rheumatol ; 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34908142

RESUMO

OBJECTIVES: Iliopsoas bursitis (IB) is a relatively rare condition that is associated with hip diseases. It can cause neurological symptoms and swelling of the lower extremities by compressing the femoral nerve and vessels. The aim of this study is to examine the prevalence of IB in patients with end-stage hip osteoarthritis. METHODS: A total of 544 patients underwent total hip arthroplasty between May 2010 and May 2019. All patients were examined using computed tomography (CT) to perform preoperative planning. We reviewed the CT images and examined the prevalence and size of IB. These lesions were divided into three types based on their shape (round type, oval type, and heart-shaped type). RESULTS: Of the 544 patients, IB was found in 37 patients. We observed the round type in 4 patients, the oval type in 31 patients, and the heart-shaped type in 2 patients. Two patients showed severe swelling in the legs and had a blood circulatory disorder of the legs. Both cases were heart-shaped bursitis. CONCLUSION: Symptomatic IB was observed in two cases, both of which had a heart shape surrounding the iliopsoas tendon and femoral neurovascular bundle. Although symptomatic IB is a rare condition, special attention is required for heart-shaped IB.

2.
J Pain Res ; 14: 3565-3571, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34815709

RESUMO

Purpose: Nonunion bone fracture can be a cause of persistent pain, but the pathophysiology remains largely unknown. The objective of this study was to identify how nonunion affect persistent pain after fracture. Specifically, we evaluated the association of neuropeptide change in dorsal root ganglia (DRG) and nerve proliferation at fracture sites with pain. Methods: Rat union and nonunion fracture models were created. A piece of latex glove was placed at the fracture site to create a nonunion model. At 6 weeks after surgery, bone healing was assessed using radiography. In addition, the presence of calcitonin gene-related peptide-immunoreactive (CGRP-IR) DRG at the level of L3 and anti-growth associated protein 43-immunoreactive (GAP43-IR) nerve fibers in the scar tissue between the bone fragments were evaluated. Pain-related behavior was assessed using forced treadmill running. Results: In radiological images at 6 weeks after surgery, callus formation was formed continuously between bone fragments in the union models. On the one hand, a clear gap was detected between fragments in nonunion models. The percentage of CGRP-IR DRG cells and the density of GAP43-IR nerve fibers in the scar tissue between the bone fragments in nonunion models was significantly higher than that in union models (p < 0.05). An increase in inflammatory cell infiltrate was observed in scar tissues in the nonunion models. During forced treadmill running, rats in the union model could run significantly longer than those in the nonunion models. Conclusion: Increased CGRP expression in DRG cells and abnormal nerve proliferation secondary to prolonged inflammation could lead to persistent pain after bone fracture. In clinical practice, early achievement of bone union may minimize the development of persistent pain after fractures.

3.
DNA Res ; 28(6)2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34677568

RESUMO

Cyanobacteria are a diverse group of Gram-negative prokaryotes that perform oxygenic photosynthesis. Cyanobacteria have been used for research on photosynthesis and have attracted attention as a platform for biomaterial/biofuel production. Cyanobacteria are also present in almost all habitats on Earth and have extensive impacts on global ecosystems. Given their biological, economical, and ecological importance, the number of high-quality genome sequences for Cyanobacteria strains is limited. Here, we performed genome sequencing of Cyanobacteria strains in the National Institute for Environmental Studies microbial culture collection in Japan. We sequenced 28 strains that can form a heterocyst, a morphologically distinct cell that is specialized for fixing nitrogen, and 3 non-heterocystous strains. Using Illumina sequencing of paired-end and mate-pair libraries with in silico finishing, we constructed highly contiguous assemblies. We determined the phylogenetic relationship of the sequenced genome assemblies and found potential difficulties in the classification of certain heterocystous clades based on morphological observation. We also revealed a bias on the sequenced strains by the phylogenetic analysis of the 16S rRNA gene including unsequenced strains. Genome sequencing of Cyanobacteria strains deposited in worldwide culture collections will contribute to understanding the enormous genetic and phenotypic diversity within the phylum Cyanobacteria.

4.
J Exp Orthop ; 8(1): 75, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34495429

RESUMO

PURPOSE: Mast cells are multifunctional in osteoarthritis (OA), and infiltration of activated mast cells likely contributes to disease severity and progression. However, the detailed mechanisms of action are unclear. The purpose of this study was to elucidate the role of mast cell infiltration in OA at histological level using a new mice model and to investigate pharmacological inhibitory effects of existing mast cell stabilizers in this model. METHODS: Mice were injected intra-articularly with monosodium iodoacetate (MIA 0.5 mg) or PBS on day 0, and PBS, with or without mast cells (MC: 1 × 106 cells) on day 14. They were divided into four groups: OA flare (MIA + MC), OA (MIA + PBS), MC non-OA (PBS + MC), and PBS non-OA (PBS + PBS). In OA flare, the MC stabilizer drug (tranilast: 400 mg/kg/day) or PBS was administered intraperitoneally from days 15 to 21. RESULTS: Histologically, modified Mankin score of the OA flare was significantly higher than that of OA (7.0 [1.8] vs. 3.3 [1.3], P < 0.05), and a larger number of mast cells was observed in OA flare than in OA (34.5 [6.3]/mm2 vs. 27.2 [2.3]/mm2, P < 0.05) on day 22. OA flare also showed acute exacerbation of pain and increased gene expression of pro-inflammatory cytokines and aggrecanase compared with OA. Administration of tranilast to OA flare-up provoked significant improvements in term of histological changes, pain, and gene expression at day 22. CONCLUSION: Our novel model possibly mimics OA flare conditions, which may open a new strategy of disease-modifying treatment for OA, focused on controlling the multiple functions of mast cells.

5.
Int J Hyperthermia ; 38(2): 46-55, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34420438

RESUMO

OBJECTIVE: To elucidate the efficacy and safety of MRgFUS in the treatment for refractory pain derived from medial knee OA. METHODS: Twenty patients with medial knee OA eligible for total knee arthroplasty were included in this prospective, non-controlled study (UMIN000010193). MRgFUS treatment was provided at the site of most severe tenderness around the medial femorotibial joint of each patient under real-time monitoring of temperature. The goal temperature of the targeted bone surface was 55 °C. Numerical rating scale (NRS) worst pain scores, Western Ontario and McMaster Universities osteoarthritis index (WOMAC) scores, EuroQol 5 dimensions index (EQ-5D) scores and pressure pain threshold (PPT) were evaluated before treatment (baseline) and at 1 week and 1, 3, 6, and 12 months post-treatment, respectively. Complications and adverse events were also assessed clinically and radiographically. RESULTS: Treatment response (a 50% or greater decrease in NRS score) was seen in 14 patients (14/19, 73.7%) at 12 months post-treatment. Mean NRS score rapidly decreased at 1 month after treatment and continued to decline through the following 12 months. At final follow-up, mean NRS score was 3.2 ± 1.9, significantly lower than at baseline (p = 0.0013). Mean WOMAC and EQ-5D scores also improved significantly from 1 month after treatment. Fifteen patients showed significant sustained increases in PPTs at the sites of most severe tenderness. No serious adverse events were observed during and after treatment. CONCLUSIONS: MRgFUS treatments were effective not only for managing refractory pain, but also for improving physical functions without adverse events in elderly patients with medial knee OA.


Assuntos
Dor Crônica , Osteoartrite do Joelho , Dor Intratável , Idoso , Humanos , Espectroscopia de Ressonância Magnética , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Estudos Prospectivos
6.
J Pain Res ; 14: 2481-2490, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34429647

RESUMO

Purpose: Degenerative long head of biceps tendon (LHBT) has been recognized as a notable pain source in patients with rotator cuff tear (RCT). Tenotomy or tenodesis of LHBT is frequently indicated together with arthroscopic rotator cuff repair (ARCR) aiming for complete pain relief; however, it has not been fully investigated whether resected LHBT is really a source of pain. The purpose of this study was to investigate expression levels of pain-associated mediators in LHBT and its association with preoperative pain profiles. Methods: Twenty-seven RCT patients who underwent ARCR with LHBT resection were included. Each LHBT was resected due to its abnormal arthroscopic findings including tenosynovitis, hypertrophy, and partial tear. Worst macroscopic lesion of the LHBT was obtained, and expression levels of substance P (SP) and nerve growth factor (NGF) were evaluated using enzyme-linked immunosorbent assay (ELISA). Ten healthy knee flexor tendons were analyzed as non-degenerative samples. Preoperatively, subjective shoulder pain VAS and pain duration were investigated. Conventional LHBT pain provocation tests (Speed, Yergason, O'Brien) were performed. Pressure pain threshold (PPT) of bilateral LHBT on the groove was recorded. Results: Levels of SP and NGF expression were significantly higher compared with non-degenerative tendons (P<0.01). Shoulder pain VAS and pain duration were not directly associated with SP and NGF expression level. Patients with positive O'Brien test expressed greater SP than negative patients (P=0.001). Significant negative correlation between the PPT ratio (ipsilateral/contralateral) and SP expression level was observed (r=-0.453, P=0.034). Conclusion: Greater expression of SP and NGF in degenerative LHBT supported our hypothesis that it would be a pain source in RCT patients. SP was likely to be expressed highly in patients with localized pressure pain hypersensitivity and positive O'Brien test (ie, altered mechanistic pain profile of LHBT), which may help when considering simultaneous LHBT resection during ARCR. Clinical Registration: UMIN000023943.

7.
J Phys Chem Lett ; 12(28): 6692-6697, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34260249

RESUMO

Phycobilisomes (PBSs) are photosynthetic antenna megacomplexes comprising pigment-binding proteins (cores and rods) joined with linker proteins. A rod-type PBS that does not have a core is connected to photosystem I (PSI) by a CpcL linker protein, which stabilizes a red-form of the phycocyanobilin (red-PCB) in the rod. However, quantitative information on the energy transfer from red-type PBS to PSI has not been determined. Herein, the isolated supercomplex of the rod-type PBS and the PSI tetramer from Anabaena sp. PCC 7120 were probed by time-resolved spectroscopy at 77 K and by decay-associated spectral analysis to show that red-PCB mediates the fast and efficient (time constant = 90 ps, efficiency = 95%) transfer of excitation energy from PCB to chlorophyll a (Chl a). According to the Förster energy transfer mechanism, this high efficiency corresponds to a 4 nm distance between red-PCB and Chl a, suggesting that ß-84 PCB in the rod acts as red-PCB.

8.
Circ Rep ; 3(6): 338-344, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34136709

RESUMO

Background: Wild-type transthyretin cardiac amyloidosis (ATTRwt-CA) is a life-threatening progressive disease. Recent studies have shown that the detection of transthyretin (TTR) amyloid in tenosynovial tissue may play an important role in the diagnosis of cardiac amyloidosis. The aim of this study was to determine the prevalence of TTR amyloid deposits in surgical tissue of patients undergoing carpal tunnel surgery and to clarify the clinical significance of concomitant cardiac examination with 99 mTc-labeled pyrophosphate (99 mTc-PYP) scintigraphy in those patients with TTR deposition. Methods and Results: We evaluated 79 consecutive patients undergoing carpal tunnel release surgery and biopsy of tenosynovial tissue. The mean (±SD) age of the patients at surgery was 71.6±12.5 years (range 30-95 years); 32 patients (41%) were male. TTR amyloid deposition in tenosynovial tissue was observed in 27 patients (34%). Sixteen of those 27 patients underwent 99 mTc-PYP scintigraphy. Of those 16 patients, 3 (19%) had Grade 2 uptake on 99 mTc-PYP scintigraphy. None of the 3 patients with a diagnosis of ATTRwt-CA had apparent cardiac symptoms and left ventricular wall thickness >13 mm. Conclusions: Concomitant cardiac examination with 99 mTc-PYP scintigraphy in patients who had TTR amyloid deposition in tenosynovial tissue resulted in the identification of 19% of patients with a diagnosis of ATTRwt-CA. This diagnostic approach seems to be useful for the early diagnosis of the disease.

9.
Elife ; 102021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34127188

RESUMO

Extracellularpolysaccharides of bacteria contribute to biofilm formation, stress tolerance, and infectivity. Cyanobacteria, the oxygenic photoautotrophic bacteria, uniquely produce sulfated extracellular polysaccharides among bacteria to support phototrophic biofilms. In addition, sulfated polysaccharides of cyanobacteria and other organisms have been focused as beneficial biomaterial. However, very little is known about their biosynthesis machinery and function in cyanobacteria. Here, we found that the model cyanobacterium, Synechocystis sp. strain PCC 6803, formed bloom-like cell aggregates embedded in sulfated extracellular polysaccharides (designated as synechan) and identified whole set of genes responsible for synechan biosynthesis and its transcriptional regulation, thereby suggesting a model for the synechan biosynthesis apparatus. Because similar genes are found in many cyanobacterial genomes with wide variation, our findings may lead elucidation of various sulfated polysaccharides, their functions, and their potential application in biotechnology.


Assuntos
Eutrofização/fisiologia , Polissacarídeos Bacterianos , Sulfatos , Synechocystis , Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/metabolismo , Sulfatos/química , Sulfatos/metabolismo , Synechocystis/metabolismo , Synechocystis/fisiologia
10.
PLoS One ; 16(6): e0252590, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34086763

RESUMO

Conditions that resemble osteoarthritis (OA) were produced by injection of sodium monoiodoacetate (MIA) into the knee joints of mice. Bone marrow derived mast cells (BMMCs) injected into the OA knee joints enhanced spontaneous pain. Since no spontaneous pain was observed when BMMCs were injected into the knee joints of control mice that had not been treated with MIA, BMMCs should be activated within the OA knee joints and release some pain-inducible factors. Protease activated receptor-2 (PAR2) antagonist (FSLLRY-NH2) almost abolished the pain-enhancing effects of BMMCs injected into the OA knee joints, suggesting that tryptase, a mast cell protease that is capable of activating PAR2, should be released from the injected BMMCs and enhance pain through activation of PAR2. When PAR2 agonist (SLIGKV-NH2) instead of BMMCs was injected into the OA knee joints, it was also enhanced pain. Apyrase, an ATP degrading enzyme, injected into the OA knee joints before BMMCs suppressed the pain enhanced by BMMCs. We showed that purinoceptors (P2X4 and P2X7) were expressed in BMMCs and that extracellular ATP stimulated the release of tryptase from BMMCs. These observations suggest that ATP may stimulate degranulation of BMMCs and thereby enhanced pain. BMMCs injected into the OA knee joints stimulated expression of IL-1ß, IL-6, TNF-α, CCL2, and MMP9 genes in the infrapatellar fat pads, and PAR2 antagonist suppressed the stimulatory effects of BMMCs. Our study suggests that intermittent pain frequently observed in OA knee joints may be due, at least partly, to mast cells through activation of PAR2 and action of ATP, and that intraarticular injection of BMMCs into the OA knee joints may provide a useful experimental system for investigating molecular mechanisms by which pain is induced in OA knee joints.


Assuntos
Trifosfato de Adenosina/metabolismo , Artrite Experimental/terapia , Dor Crônica/patologia , Articulação do Joelho/patologia , Mastócitos/transplante , Receptor PAR-2/metabolismo , Trifosfato de Adenosina/análise , Animais , Artrite Experimental/induzido quimicamente , Artrite Experimental/patologia , Células da Medula Óssea/citologia , Quimiocina CXCL2/genética , Quimiocina CXCL2/metabolismo , Ácido Quenodesoxicólico/análogos & derivados , Ácido Quenodesoxicólico/toxicidade , Dor Crônica/etiologia , Modelos Animais de Doenças , Articulação do Joelho/metabolismo , Masculino , Mastócitos/citologia , Mastócitos/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Oligopeptídeos/administração & dosagem , Receptor PAR-2/agonistas , Receptor PAR-2/antagonistas & inibidores , Receptores Purinérgicos/metabolismo , Líquido Sinovial/metabolismo
11.
J Pain Res ; 14: 1113-1118, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33907458

RESUMO

Purpose: Patients with knee osteoarthritis (OA) complain of various types of pain, divided into two main categories: pain on movement and pain at rest. A thorough understanding of pain is essential for managing knee OA; however, few studies have investigated the mechanisms underlying the two different types of pain. This study aimed to clarify the predisposing factors for pain in patients with knee OA with a focus on differences between pain on walking and pain at rest. Patients and Methods: This study involved 93 patients, aged 44-90 years, with knee OA, including 74 women. We assessed demographic variables (sex, age, body mass index [BMI], side), visual analogue scale (VAS) score on walking, VAS score at rest, Kellgren and Lawrence (KL) grade on radiograph, synovitis score and bone marrow lesion (BML) score on magnetic resonance imaging, and pressure pain threshold (PPT), and used univariate and multiple regression analyses to investigate factors predisposing patients to pain at rest or pain on walking. Results: In the univariate analyses, we found significant correlations between VAS score on walking and BMI (r=0.31, p<0.01), KL grade (r=0.40, p<0.01), synovitis score (r=0.26, p=0.01), and BML score (r=0.36, p<0.01), whereas VAS score at rest correlated with PPT (r=-0.23, p=0.02) and BMI (r= 0.26, p=0.01). Multiple regression analysis showed that significant explanatory factors for VAS score on walking were BMI (ß=0.22, p=0.03) and KL grade (ß=0.27, p=0.03). By contrast, PPT was the only significant explanatory factor for VAS score at rest (ß=-0.27, p=0.01). Conclusion: Predisposing factors were significantly different between pain on walking and pain at rest, indicating that different pain mechanisms exist in the two types of pain. Pain on walking was more strongly associated with mechanical and structural factors, while pain at rest was associated with mechanical hyperalgesia of the knee. Clinical Registration: University Hospital Medical Information Network Clinical Trials Registration number; 000041190.

12.
J Pain Res ; 14: 285-295, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33568937

RESUMO

Purpose: Clinically, arthrogenic muscle inhibition (AMI) has a negative impact on functional recovery in musculoskeletal disorders. One possible technique to relieve AMI is motor imagery, which is widely used in neurological rehabilitation to enhance motor neuron excitability. The purpose of this study was to verify the efficacy of visually-assisted motor imagery against AMI using a human experimental pain model. Methods: Ten healthy volunteers were included. Experimental ankle pain was induced by hypertonic saline infusion into unilateral Kager's fat pad. Isotonic saline was used as control. Subjects were instructed to imagine while watching a movie in which repetitive motion of their own ankle or fingers was shown. H-reflex normalized by the motor response (H/M ratio) on soleus muscle, maximal voluntary contraction (MVC) force of ankle flexion, and contractile activities of the calf muscles during MVC were recorded at baseline, pre-intervention, post-intervention, and 10 minutes after the pain had subsided. Results: Hypertonic saline produced continuous and constant peri-ankle pain (VAS peak [median]= 6.7 [2.1-8.4] cm) compared to isotonic saline (0 [0-0.8] cm). In response to pain, there were significant decreases in the H/M ratio, MVC and contractile activities (P<0.01), all of which were successfully reversed after the ankle motion imagery. In contrast, no significant changes were observed with the finger motion imagery. Conclusion: Visually-assisted motor imagery improved the pain-induced AMI. Motor imagery of the painful joint itself would efficiently work for relieving AMI. This investigation possibly shows the potential of a novel and versatile approach against AMI for patients with musculoskeletal pain.

13.
Mod Rheumatol ; 31(5): 1038-1044, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33274662

RESUMO

OBJECTIVES: To elucidate the prevalence and risk factors of chronic postsurgical pain (CPSP) after primary total knee arthroplasty (TKA) in Japanese population. METHODS: Consecutive patients undergoing primary TKA in a Japanese tertiary hospital (211 knees) were assessed. CPSP after TKA was defined as moderate to severe pain (VAS >30 mm), either at rest or during walking, one year after surgery. Clinical and radiographic data were compared between CPSP and non-CPSP groups and multivariate logistic regression was used to identify predictors of CPSP. RESULTS: The prevalence of CPSP was 8.8%. CPSP group showed significantly higher preoperative WOMAC subscales (pain, function and stiffness), higher rate of postoperative coronal malalignment (femorotibial angle >178° or <170°) and larger varus angle of tibial component compared with non-CPSP group. Logistic regression analysis revealed that preoperative higher WOMAC pain and postoperative coronal malalignment were independent risk factors of CPSP. In a subgroup analysis of patients with well-aligned TKA, preoperative pain VAS at rest was the only risk factor of CPSP. CONCLUSION: Preoperative severe pain and postoperative coronal malalignment were independent risk factors of CPSP after TKA. Preoperative pain management in patients with severe pain and good coronal alignment after TKA possibly minimize the development of CPSP.


Assuntos
Osteoartrite do Joelho , Dor Pós-Operatória , Artroplastia do Joelho/efeitos adversos , Humanos , Japão/epidemiologia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/etiologia , Estudos Prospectivos
14.
J Orthop Surg (Hong Kong) ; 28(3): 2309499020962860, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33078676

RESUMO

PURPOSE: To evaluate cup-positioning accuracy in total hip arthroplasty (THA) using a novel angle-adjusting alignment guide with laser pointer and determine whether level of surgical experience affects accuracy of cup placement or not. METHODS: We included 117 hips in 104 patients who underwent THA using the novel guide. We retrospectively reviewed 44 hips in 40 patients who underwent THA before the novel guide was introduced. We compared differences in cup angles between the novel guide group and the conventional guide group as well as the discrepancies in targeted angles between the experienced surgeon group and the inexperienced surgeon group. RESULTS: There were 114/117 hips (97.4%) within the Lewinnek safe zone in the novel guide group and 32/44 hips (72.7%) within the safe zone in the conventional guide group. There were significantly fewer outliers in the novel guide group (p < 0.001). In the experienced surgeon group, the mean absolute errors in inclination and anteversion were 2.0 ± 1.7° and 2.1 ± 2.3°, respectively; which were not significantly different from those in the inexperienced surgeon group (2.3 ± 2.1° and 2.8 ± 2.3°, respectively). CONCLUSION: The novel angle-adjusting alignment guide with laser pointer is a simple tool that provides better accuracy of cup position than that obtained using conventional guides. Accurate cup placement is possible using the novel guide, regardless of surgeons' experience.


Assuntos
Acetábulo/cirurgia , Artroplastia de Quadril/métodos , Prótese de Quadril , Cirurgia Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Lasers , Masculino , Pessoa de Meia-Idade , Posicionamento do Paciente , Reprodutibilidade dos Testes , Estudos Retrospectivos
15.
Proc Natl Acad Sci U S A ; 117(27): 15573-15580, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571944

RESUMO

Cyanobacteriochromes (CBCRs) are small, bistable linear tetrapyrrole (bilin)-binding light sensors which are typically found as modular components in multidomain cyanobacterial signaling proteins. The CBCR family has been categorized into many lineages that roughly correlate with their spectral diversity, but CBCRs possessing a conserved DXCF motif are found in multiple lineages. DXCF CBCRs typically possess two conserved Cys residues: a first Cys that remains ligated to the bilin chromophore and a second Cys found in the DXCF motif. The second Cys often forms a second thioether linkage, providing a mechanism to sense blue and violet light. DXCF CBCRs have been described with blue/green, blue/orange, blue/teal, and green/teal photocycles, and the molecular basis for some of this spectral diversity has been well established. We here characterize AM1_1499g1, an atypical DXCF CBCR that lacks the second cysteine residue and exhibits an orange/green photocycle. Based on prior studies of CBCR spectral tuning, we have successfully engineered seven AM1_1499g1 variants that exhibit robust yellow/teal, green/teal, blue/teal, orange/yellow, yellow/green, green/green, and blue/green photocycles. The remarkable spectral diversity generated by modification of a single CBCR provides a good template for multiplexing synthetic photobiology systems within the same cellular context, thereby bypassing the time-consuming empirical optimization process needed for multiple probes with different protein scaffolds.


Assuntos
Proteínas de Bactérias/metabolismo , Evolução Molecular , Luz , Fotorreceptores Microbianos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/efeitos da radiação , Cor , Cianobactérias/genética , Cianobactérias/metabolismo , Cianobactérias/efeitos da radiação , Mutagênese Sítio-Dirigida , Nostoc/genética , Nostoc/metabolismo , Nostoc/efeitos da radiação , Fotobiologia/métodos , Fotorreceptores Microbianos/efeitos da radiação , Biologia Sintética/métodos , Tetrapirróis/metabolismo
17.
J Gen Appl Microbiol ; 66(2): 147-152, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32224605

RESUMO

Second messenger molecules are crucial components of environmental signaling systems to integrate multiple inputs and elicit physiological responses. Among various kinds of second messengers, cyclic nucleotides cAMP and cyclic di-GMP (c-di-GMP) play pivotal roles in bacterial environmental responses. However, how these signaling systems are interconnected for a concerted regulation of cellular physiology remains elusive. In a thermophilic cyanobacterium Thermosynechococcus vulcanus strain RKN, incident light color is sensed by cyanobacteriochrome photoreceptors to transduce the light information to the levels of c-di-GMP, which induces cellular aggregation probably via cellulose synthase activation. Herein, we identified that Tlr0485, which is composed of a cGMP-specific phosphodiesterases, adenylate cyclases, and FhlA (GAF) domain and an HD-GYP domain, is a cAMP-activated c-di-GMP phosphodiesterase. We also show biochemical evidence that the two class-III nucleotide cyclases, Cya1 and Cya2, are both adenylate cyclases to produce cAMP in T. vulcanus. The prevalence of cAMP-activated c-di-GMP phosphodiesterase genes in cyanobacterial genomes suggests that the direct crosstalk between cAMP and c-di-GMP signaling systems may be crucial for cyanobacterial environmental responses.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/metabolismo , Proteínas de Bactérias/metabolismo , AMP Cíclico/metabolismo , GMP Cíclico/análogos & derivados , Sistemas do Segundo Mensageiro , 3',5'-GMP Cíclico Fosfodiesterases/genética , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Proteínas de Bactérias/genética , Cromatografia Líquida de Alta Pressão , GMP Cíclico/metabolismo , Eletroforese em Gel de Poliacrilamida , Mutação , Domínios Proteicos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Thermosynechococcus/enzimologia , Thermosynechococcus/genética
18.
Case Rep Orthop ; 2020: 6859474, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32257484

RESUMO

This study aimed at presenting a rare nontraumatic spondylolisthesis of the axis and considering its possible cause. Traumatic spondylolisthesis of the axis, called hangman's fracture, frequently occurs as a high-energy trauma. However, nontraumatic spondylolisthesis of the axis is quite rare, and relevant literature on this condition is scarce. We reported a case of a 49-year-old man who had spondylolisthesis of the axis without experiencing a traumatic episode. Plain radiograph and CT image showed 7.0 mm anterolisthesis of the axis. Both C2 and C3 facet joints positioned asymmetrically, and the unilateral side oriented coronally, which was less resistant to rotational motion. These facet joint abnormalities could cause segmental instability and spondylolisthesis of the axis. Due to the resultant myelopathy, the slip with cord compression was surgically corrected by posterior decompression with instrumented fusion.

19.
J Gen Appl Microbiol ; 66(2): 116-120, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32213752

RESUMO

Heterologous production of a useful carotenoid astaxanthin was achieved in a cyanobacterium Synechocystis sp. PCC 6803 with the aid of marine bacterial genes. Astaxanthin and its intermediates emerged at high levels, whereas ß-carotene and zeaxanthin disappeared in the strain. Total carotenoid accumulation was nearly two fold compared with wild type. The astaxanthin-producing strain was capable of only growing heterotrophically, which was likely due to the absence of ß-carotene. Further enhanced accumulation was pursued by gene overexpression for possible rate-limiting steps in the biosynthesis pathway.


Assuntos
Caulobacteraceae/enzimologia , Oxigenases de Função Mista/metabolismo , Oxigenases/metabolismo , Synechocystis/genética , Synechocystis/metabolismo , Vias Biossintéticas , Caulobacteraceae/genética , Cromatografia Líquida de Alta Pressão , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Engenharia Metabólica , Microrganismos Geneticamente Modificados , Oxigenases de Função Mista/genética , Oxigenases/genética , Transformação Bacteriana , Xantofilas/metabolismo
20.
iScience ; 23(3): 100936, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32146329

RESUMO

Cyanobacteriochrome (CBCRs) photoreceptors show various photochemical properties, but their ecophysiological functions remain elusive. Here, we report that the blue/green CBCRs SesA/B/C can serve as physiological sensors of cell density. Because cyanobacterial cells show lower transmittance of blue light than green light, higher cell density gives more green-light-enriched irradiance to cells. The cell-density-dependent suppression of cell aggregation under blue-/green-mixed light and white light conditions support this idea. Such a sensing mechanism may provide information about the cell position in cyanobacterial mats in hot springs, the natural habitat of Thermosynechococcus. This cell-position-dependent SesA/B/C-mediated regulation of cellular sessility (aggregation) might be ecophysiologically essential for the reorganization and growth of phototrophic mats. We also report that the green-light-induced dispersion of cell aggregates requires red-light-driven photosynthesis. Blue/green CBCRs might work as shade detectors in a different niche than red/far-red phytochromes, which may be why CBCRs have evolved in cyanobacteria.

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