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1.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38265871

RESUMO

Previous postmortem brain studies have revealed disturbed myelination in the intracortical regions in patients with schizophrenia, possibly reflecting anomalous brain maturational processes. However, it currently remains unclear whether this anomalous myelination is already present in early illness stages and/or progresses during the course of the illness. In this magnetic resonance imaging study, we examined gray/white matter contrast (GWC) as a potential marker of intracortical myelination in 63 first-episode schizophrenia (FESz) patients and 77 healthy controls (HC). Furthermore, we investigated the relationships between GWC findings and clinical/cognitive variables in FESz patients. GWC in the bilateral temporal, parietal, occipital, and insular regions was significantly higher in FESz patients than in HC, which was partly associated with the durations of illness and medication, the onset age, and lower executive and verbal learning performances. Because higher GWC implicates lower myelin in the deeper layers of the cortex, these results suggest that schizophrenia patients have less intracortical myelin at the time of their first psychotic episode, which underlies lower cognitive performance in early illness stages.


Assuntos
Esquizofrenia , Substância Branca , Humanos , Esquizofrenia/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Córtex Cerebral/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Imageamento por Ressonância Magnética/métodos , Cognição
2.
J Struct Biol ; 216(2): 108074, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38432597

RESUMO

Calcium carbonate is present in many biominerals, including in the exoskeletons of crustaceans and shells of mollusks. High Mg-containing calcium carbonate was synthesized by high temperatures, high pressures or high molecular organic matter. For example, biogenic high Mg-containing calcite is synthesized under strictly controlled Mg concentration at ambient temperature and pressure. The spines of sea urchins consist of calcite, which contain a high percentage of magnesium. In this study, we investigated the factors that increase the magnesium content in calcite from the spines of the sea urchin, Heliocidaris crassispina. X-ray diffraction and inductively coupled plasma mass spectrometry analyses showed that sea urchin spines contain about 4.8% Mg. The organic matrix extracted from the H. crassispina spines induced the crystallization of amorphous phase and synthesis of magnesium-containing calcite, while amorphous was synthesized without SUE (sea urchin extract). In addition, aragonite was synthesized by SUE treated with protease-K. HC tropomyosin was specifically incorporated into Mg precipitates. Recombinant HC-tropomyosin induced calcite contained 0.1-2.5% Mg synthesis. Western blotting of sea urchin spine extracts confirmed that HC tropomyosin was present in the purple sea urchin spines at a protein weight ratio of 1.5%. These results show that HC tropomyosin is one factor that increases the magnesium concentration in the calcite of H. crassispina spines.


Assuntos
Carbonato de Cálcio , Magnésio , Ouriços-do-Mar , Tropomiosina , Animais , Carbonato de Cálcio/química , Carbonato de Cálcio/metabolismo , Ouriços-do-Mar/metabolismo , Tropomiosina/química , Tropomiosina/metabolismo , Magnésio/química , Difração de Raios X , Cristalização
3.
J Biol Chem ; 299(8): 105069, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37468100

RESUMO

Mn2+ is an essential nutrient whose concentration is tightly controlled in bacteria. In Bacillus subtilis, the Mn2+-activated transcription factor MntR controls Mn2+ transporter genes. However, factors regulating intracellular Mn2+ concentration are incompletely understood. Here, we found that glucose addition induces an increase in intracellular Mn2+ concentration. We determined this upshift was mediated by glucose induction of the major Mn2+ importer gene mntH by the transcription factor AhrC, which is known to be involved in arginine metabolism and to be indirectly induced by glucose. In addition, we identified novel AhrC-regulated genes encoding the Mn2+ importer YcsG and the ABC-type exporter YknUV. We found the expression of these genes was also regulated by glucose and contributes to the glucose induction of Mn2+ concentrations. ycsG expression is regulated by MntR as well. Furthermore, we analyzed the interaction of AhrC and MntR with the promoter driving ycsG expression and examined the Mn2+-dependent induction of this promoter to identify the transcription factors responsible for the Mn2+ induction. RNA-Seq revealed that disruption of ahrC and mntR affected the expression of 502 and 478 genes, respectively (false discovery rate, <0.001, log2[fold change] ≥ |2|. The AhrC- and/or MntR-dependent expression of twenty promoters was confirmed by LacZ analysis, and AhrC or MntR binding to some of these promoters was observed via EMSA. The finding that glucose promotes an increase in intracellular Mn2+ levels without changes in extracellular Mn2+ concentrations is reasonable for the bacterium, as intracellular Mn2+ is required for enzymes and pathways mediating glucose metabolism.


Assuntos
Bacillus subtilis , Proteínas de Bactérias , Glucose , Manganês , Fatores de Transcrição , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Glucose/metabolismo , Glucose/farmacologia , Homeostase , Manganês/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
J Mol Evol ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864871

RESUMO

Pif is a shell matrix protein (SMP) identified in the nacreous layer of Pinctada fucata (Pfu) comprised two proteins, Pif97 and Pif 80. Pif97 contains a von Willebrand factor A (VWA) and chitin-binding domains, whereas Pif80 can bind calcium carbonate crystals. The VWA domain is conserved in the SMPs of various mollusk species; however, their phylogenetic relationship remains obscure. Furthermore, although the VWA domain participates in protein-protein interactions, its role in shell formation has not been established. Accordingly, in the current study, we investigate the phylogenetic relationship between PfuPif and other VWA domain-containing proteins in major mollusk species. The shell-related proteins containing VWA domains formed a large clade (the Pif/BMSP family) and were classified into eight subfamilies with unique sequential features, expression patterns, and taxa diversity. Furthermore, a pull-down assay using recombinant proteins containing the VWA domain of PfuPif 97 revealed that the VWA domain interacts with five nacreous layer-related SMPs of P. fucata, including Pif 80 and nacrein. Collectively, these results suggest that the VWA domain is important in the formation of organic complexes and participates in shell mineralisation.

5.
Chemistry ; : e202401557, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38868960

RESUMO

Anhydrous calcium carbonate crystals exist as three polymorphs: calcite, aragonite, and vaterite. Although vaterite is a metastable phase rarely found in the geological environment, it is intriguing that various biominerals are composed of vaterite. The processes of stable vaterite formation in biological systems cannot be understood without elucidating the nature of vaterite. The crystal structure of vaterite has been discussed for nearly a century but is still an open question. Here we propose the actual structure of vaterite by combining atomic imaging and diffraction analysis with simulations of disordered stacking sequences. Vaterite basically appears as layers of hexagonal calcium planes and carbonate (CO32-)-containing sheets stacked with +60°, -60°, or 180° rotations from the underlying layer. However, equivalent carbonate positions in alternating layers are forbidden, and four-layer stacking in which the fourth layer rotates 180° relative to the first layer are predominant, forming an orthogonal reciprocal lattice in diffraction patterns. These stacking characteristics replicate the intensity distribution in the electron and X-ray diffraction patterns. This study has almost completely elucidated the crystal structure and stacking sequence of vaterite. Our findings provide insights into the thermodynamic stability of vaterite, which facilitates comprehension of the biomineralization processes and growth dynamics of calcium carbonate.

6.
Mol Psychiatry ; 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37537281

RESUMO

Differential diagnosis is sometimes difficult in practical psychiatric settings, in terms of using the current diagnostic system based on presenting symptoms and signs. The creation of a novel diagnostic system using objective biomarkers is expected to take place. Neuroimaging studies and others reported that subcortical brain structures are the hubs for various psycho-behavioral functions, while there are so far no neuroimaging data-driven clinical criteria overcoming limitations of the current diagnostic system, which would reflect cognitive/social functioning. Prior to the main analysis, we conducted a large-scale multisite study of subcortical volumetric and lateralization alterations in schizophrenia, bipolar disorder, major depressive disorder, and autism spectrum disorder using T1-weighted images of 5604 subjects (3078 controls and 2526 patients). We demonstrated larger lateral ventricles volume in schizophrenia, bipolar disorder, and major depressive disorder, smaller hippocampus volume in schizophrenia and bipolar disorder, and schizophrenia-specific smaller amygdala, thalamus, and accumbens volumes and larger caudate, putamen, and pallidum volumes. In addition, we observed a leftward alteration of lateralization for pallidum volume specifically in schizophrenia. Moreover, as our main objective, we clustered the 5,604 subjects based on subcortical volumes, and explored whether data-driven clustering results can explain cognitive/social functioning in the subcohorts. We showed a four-biotype classification, namely extremely (Brain Biotype [BB] 1) and moderately smaller limbic regions (BB2), larger basal ganglia (BB3), and normal volumes (BB4), being associated with cognitive/social functioning. Specifically, BB1 and BB2-3 were associated with severe and mild cognitive/social impairment, respectively, while BB4 was characterized by normal cognitive/social functioning. Our results may lead to the future creation of novel biological data-driven psychiatric diagnostic criteria, which may be expected to be useful for prediction or therapeutic selection.

7.
Mol Psychiatry ; 28(11): 4915-4923, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37596354

RESUMO

According to the operational diagnostic criteria, psychiatric disorders such as schizophrenia (SZ), bipolar disorder (BD), major depressive disorder (MDD), and autism spectrum disorder (ASD) are classified based on symptoms. While its cluster of symptoms defines each of these psychiatric disorders, there is also an overlap in symptoms between the disorders. We hypothesized that there are also similarities and differences in cortical structural neuroimaging features among these psychiatric disorders. T1-weighted magnetic resonance imaging scans were performed for 5,549 subjects recruited from 14 sites. Effect sizes were determined using a linear regression model within each protocol, and these effect sizes were meta-analyzed. The similarity of the differences in cortical thickness and surface area of each disorder group was calculated using cosine similarity, which was calculated from the effect sizes of each cortical regions. The thinnest cortex was found in SZ, followed by BD and MDD. The cosine similarity values between disorders were 0.943 for SZ and BD, 0.959 for SZ and MDD, and 0.943 for BD and MDD, which indicated that a common pattern of cortical thickness alterations was found among SZ, BD, and MDD. Additionally, a generally smaller cortical surface area was found in SZ and MDD than in BD, and the effect was larger in SZ. The cosine similarity values between disorders were 0.945 for SZ and MDD, 0.867 for SZ and ASD, and 0.811 for MDD and ASD, which indicated a common pattern of cortical surface area alterations among SZ, MDD, and ASD. Patterns of alterations in cortical thickness and surface area were revealed in the four major psychiatric disorders. To our knowledge, this is the first report of a cross-disorder analysis conducted on four major psychiatric disorders. Cross-disorder brain imaging research can help to advance our understanding of the pathogenesis of psychiatric disorders and common symptoms.


Assuntos
Transtorno do Espectro Autista , Transtorno Bipolar , Transtorno Depressivo Maior , Transtornos Mentais , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/patologia , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/patologia , Transtorno Bipolar/diagnóstico por imagem , Transtorno Bipolar/patologia , Transtornos Mentais/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Imageamento por Ressonância Magnética/métodos
8.
Langmuir ; 40(16): 8373-8392, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38606767

RESUMO

Amorphous calcium carbonate (ACC) is an important precursor phase for the formation of aragonite crystals in the shells of Pinctada fucata. To identify the ACC-binding protein in the inner aragonite layer of the shell, extracts from the shell were used in the ACC-binding experiments. Semiquantitative analyses using liquid chromatography-mass spectrometry revealed that paramyosin was strongly associated with ACC in the shell. We discovered that paramyosin, a major component of the adductor muscle, was included in the myostracum, which is the microstructure of the shell attached to the adductor muscle. Purified paramyosin accumulates calcium carbonate and induces the prism structure of aragonite crystals, which is related to the morphology of prism aragonite crystals in the myostracum. Nuclear magnetic resonance measurements revealed that the Glu-rich region was bound to ACC. Activity of the Glu-rich region was stronger than that of the Asp-rich region. These results suggest that paramyosin in the adductor muscle is involved in the formation of aragonite prisms in the myostracum.


Assuntos
Exoesqueleto , Carbonato de Cálcio , Pinctada , Tropomiosina , Animais , Pinctada/química , Pinctada/metabolismo , Carbonato de Cálcio/química , Carbonato de Cálcio/metabolismo , Exoesqueleto/química , Exoesqueleto/metabolismo , Tropomiosina/química , Tropomiosina/metabolismo
9.
Environ Sci Technol ; 58(5): 2404-2412, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38252973

RESUMO

Carbon capture, utilization, and storage (CCUS) are widely recognized as a promising technology for mitigating climate change. CO2 mineralization using Ca-rich fluids and high-concentration CO2 gas has been studied extensively. However, few studies have reported CO2 mineralization with atmospheric CO2, owing to the difficulty associated with its low concentration. In seawater, the biomineralization process promotes Ca accumulation and CaCO3 precipitation, assisted by specific organic matter. In this study, we examined the conversion of atmospheric CO2 into CaCO3 in seawater using shell powders (Pinctada fucata, Haliotis discus, Crassostrea gigas, Mizuhopecten yessoensis, Turbo sazae, and Saxidomus purpurata). Among the six species, the shell powder of S. purpurata showed the highest rate of CaCO3 formation and recovery of CaCO3. NaClO treatment test revealed that the organic matter in the shells enhanced the CO2 mineralization. All materials used in this study, including atmospheric CO2, seawater, and shells, are economically feasible for large-scale applications. Using shell powder for CO2 mineralization in seawater embodies an innovative technological advancement to address climate change.


Assuntos
Dióxido de Carbono , Gastrópodes , Animais , Pós , Água do Mar , Calcificação Fisiológica
10.
Cereb Cortex ; 33(13): 8456-8464, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37099431

RESUMO

Disrupted functional connectivity (FC) of the default mode network (DMN) may have a pathophysiological role in schizophrenia. However, functional magnetic resonance imaging (fMRI) of the DMN in schizophrenia patients has shown inconsistent results. It also remains unclear whether individuals with at-risk mental state (ARMS) have an altered DMN connectivity and whether it is related to clinical characteristics. This fMRI study examined resting-state FCs of the DMN and its relevance to clinical/cognitive variables in 41 schizophrenia patients, 31 ARMS individuals, and 65 healthy controls. Compared with controls, schizophrenia patients had significantly increased FCs within the DMN and between the DMN and diverse cortical areas, whereas ARMS patients had increased FCs only between the DMN and occipital cortex. FC of the lateral parietal cortex with superior temporal gyrus was positively correlated with negative symptoms in schizophrenia, whereas FC of that with interparietal sulcus was negatively correlated with general cognitive impairment in ARMS. Our findings suggest that increased FCs between the DMN and visual network commonly seen in schizophrenia and ARMS subjects may reflect a network-level disturbance representing a general vulnerability to psychosis. In addition, FC changes related to the lateral parietal cortex may underpin clinical characteristics of ARMS and schizophrenia subjects.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Rede de Modo Padrão , Descanso , Transtornos Psicóticos/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
11.
Mol Biol Evol ; 39(7)2022 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-35796746

RESUMO

Several types of shell matrix proteins (SMPs) have been identified in molluskan shells. Their diversity is the consequence of various molecular processes, including domain shuffling and gene duplication. However, the evolutionary origin of most SMPs remains unclear. In this study, we investigated the evolutionary process EGF-like and zona pellucida (ZP) domains containing SMPs. Two types of the proteins (EGF-like protein (EGFL) and EGF-like and ZP domains containing protein (EGFZP)) were found in the pearl oyster, Pinctada fucata. In contrast, only EGFZP was identified in the gastropods. Phylogenetic analysis and genomic arrangement studies showed that EGFL and EGFZP formed a clade in bivalves, and their encoding genes were localized in tandem repeats on the same scaffold. In P. fucata, EGFL genes were expressed in the outer part of mantle epithelial cells are related to the calcitic shell formation. However, in both P. fucata and the limpet Nipponacmea fuscoviridis, EGFZP genes were expressed in the inner part of the mantle epithelial cells are related to aragonitic shell formation. Furthermore, our analysis showed that in P. fucata, the ZP domain interacts with eight SMPs that have various functions in the nacreous shell mineralization. The data suggest that the ZP domain can interact with other SMPs, and EGFL evolution in pterimorph bivalves represents an example of neo-functionalization that involves the acquisition of a novel protein through gene duplication.


Assuntos
Fator de Crescimento Epidérmico , Pinctada , Exoesqueleto/metabolismo , Animais , Carbonato de Cálcio/metabolismo , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/metabolismo , Filogenia , Pinctada/genética , Zona Pelúcida
12.
Proc Biol Sci ; 290(1991): 20221216, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36651043

RESUMO

Biomineralization is one of the key biochemical processes in calcifying bivalve species such as oysters that is affected by ocean acidification (OA). Larval life stages of oysters are made of aragonite crystals whereas the adults are made of calcite and/or aragonite. Though both calcite and aragonite are crystal polymorphs of calcium carbonate, they have different mechanical properties and hence it is important to study the micro and nano structure of different life stages of oyster shells under OA to understand the mechanisms by which OA affects biomineralization ontogeny. Here, we have studied the larval and juvenile life stages of an economically and ecologically important estuarine oyster species, Crassostrea hongkongensis, under OA with focus over shell fabrication under OA (pHNBS 7.4). We also look at the effect of parental exposure to OA on larvae and juvenile microstructure. The micro and nanostructure characterization reveals directional fabrication of oyster shells, with more organized structure as biomineralization progresses. Under OA, both the larval and juvenile stages show directional dissolution, i.e. the earlier formed shell layers undergo dissolution at first, owing to longer exposure time. Despite dissolution, the micro and nanostructure of the shell remains unaffected under OA, irrespective of parental exposure history.


Assuntos
Crassostrea , Água do Mar , Animais , Água do Mar/química , Larva , Concentração de Íons de Hidrogênio , Acidificação dos Oceanos , Solubilidade , Exoesqueleto/química , Carbonato de Cálcio/análise , Dióxido de Carbono/análise
13.
Chembiochem ; 24(14): e202300221, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37232370

RESUMO

Collimonas sp. (D-25), found in the soil of Akita Prefecture, is a gram-negative bacterium with the ability to synthesize gold nanoparticles (AuNPs). During the synthesis of AuNPs, one specific protein (DP-1) was found to have disappeared in the sonicated solution of the bacterium. Recombinant DP-1 (rDP-1) from Escherichia coli BL21 (DE3) was used to study the effect of DP-1 on the synthesis of AuNPs. AuNPs synthesized with rDP-1 result in small, stabilized nanoparticles. AuNPs synthesized by DP-1 retained the stability of both the dispersion and nano-size particles under high salt concentrations. Isothermal titration calorimetry was employed to investigate the bonding ratio of rDP-1 to AuNPs. Several thousand rDP-1 proteins are attached to the surface of an AuNP to form a protein corona containing multiple layers. These results suggest that DP-1 obtained from D-25 has a size and stability control function during AuNP synthesis.


Assuntos
Nanopartículas Metálicas , Coroa de Proteína , Ouro/química , Nanopartículas Metálicas/química , Bactérias/metabolismo , Tamanho da Partícula
14.
Artigo em Inglês | MEDLINE | ID: mdl-36951910

RESUMO

Three bacterial strains, KC07075, KC07079 and KC07084T, were isolated from the oral cavity of cats in 2007 in Japan. These strains were Gram-negative rods, exhibited gliding motility, grew in air with 5 % CO2, and showed oxidase activity, but not catalase activity. The 16S rRNA gene sequences of the three strains were 100 % identical. The 16S rRNA gene sequence of strain KC07084T showed 92.1 and 91.9% identity to the type strains of Capnocytophaga canis and Capnocytophaga felis, respectively, and showed 89.3-91.6% identity to other Capnocytophaga species. The major cellular fatty acids of strain KC07084T were iso-C15 : 0 (58.4 %) and summed feature 11 (13.1 %). The G+C content of DNA from strain KC07084T was 33.7 mol%, and the genome size was 2.92 Mbp. Strains KC07075, KC07079 and KC07084T showed digital DNA-DNA hybridization values (dDDH) values of 99.9 % and average nucleotide identity (ANI) values of 99.98 % with each other, strain KC07084T had dDDH values of 18.7-28.2 % and ANI values of 67.12-72.30 % to the type strains of other Capnocytophaga species. All known species of the genus Capnocytophaga inhabiting the oral cavity of dogs and cats have catalase activity, but the three strains, including type strain KC07084T, lacked catalase activity. These results of the phylogenetic analysis of the 16S rRNA gene sequence, biochemical characteristics, and dDDH and ANI values suggest that strain KC07084T represents a novel species. We propose the name Capnocytophaga catalasegens sp. nov., with KC07084T as the type strain (=JCM 32682T=DSM 107252T).


Assuntos
Doenças do Gato , Doenças do Cão , Animais , Gatos , Cães , Ácidos Graxos/química , Análise de Sequência de DNA , Capnocytophaga , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases , Técnicas de Tipagem Bacteriana , Boca , Hibridização de Ácido Nucleico
15.
Cereb Cortex ; 32(10): 2245-2253, 2022 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-34649274

RESUMO

Although some individuals with at-risk mental states (ARMS) develop overt psychosis, surrogate markers which can reliably predict a future onset of psychosis are not well established. The dorsal lateral prefrontal cortex (DLPFC) is thought to be involved in psychotic disorders such as schizophrenia. In this study, 73 ARMS patients and 74 healthy controls underwent 1.5-T 3D magnetic resonance imaging scans at three sites. Using labeled cortical distance mapping, cortical thickness, gray matter (GM) volume, and surface area of DLPFC were estimated. These measures were compared across the diagnostic groups. We also evaluated cognitive function among 36 ARMS subjects to clarify the relationships between the DLPFC morphology and cognitive performance. The GM volume of the right DLPFC was significantly reduced in ARMS subjects who later developed frank psychosis (ARMS-P) relative to those who did not (P = 0.042). There was a positive relationship between the right DLPFC volume and the duration prior to the onset of frank psychosis in ARMS-P subjects (r = 0.58, P = 0.018). Our data may suggest that GM reduction of the DLPFC might be a potential marker of future onset of psychosis in individuals with ARMS.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Córtex Pré-Frontal/patologia , Transtornos Psicóticos/patologia
16.
Eur J Oral Sci ; 131(3): e12929, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36929523

RESUMO

This study aimed to evaluate the effects of phosphoproteins on bacterial mineralization. Dental calculus formation is attributed to bacterial mineralization in the oral cavity; however, the influence of phosphoproteins (which are abundant in saliva) is not clear. The model bacterium Escherichia coli was suspended in a calcification solution containing casein as a model phosphoprotein. To evaluate mineralization independent of bacterial metabolism, bacteria killed by heat treatment at 70°C were compared with viable bacteria. After incubation at 37°C for 24 h, the mode of calcification was observed using electron microscopy and energy dispersive x-ray spectroscopy. Solutions without casein produced precipitation in solution, which was identical to that in experiments without bacteria. In contrast, calcification solutions with 200 ppm casein only produced calcium phosphate deposition intracellularly. Without heat treatment, intracellular calcification rarely occurred, even when casein was added. Thus, phosphoproteins promoted intracellular calcification of dead bacteria; this is similar to the calcification of insoluble matrices, such as collagen fibrils, promoted by acidic polymers. We concluded that intracellular calcification is caused by the collagen fibril-like behavior of dead bacteria. The promotion of intracellular calcification of dead bacteria by phosphoproteins suggested a basic principle of dental calculus formation.


Assuntos
Caseínas , Fosfoproteínas , Humanos , Fosfoproteínas/química , Caseínas/farmacologia , Caseínas/química , Cálculos Dentários/química , Bactérias , Colágeno , Calcificação Fisiológica
17.
Acta Neuropsychiatr ; : 1-6, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37612148

RESUMO

OBJECTIVE: A range of neuropathological changes occur in the brains of individuals with adult Niemann-Pick type C disease (NPC), a recessive disorder of cholesterol trafficking that results in accumulation of cholesterol and gangliosides in lysosomes, particularly in neurons. One of the most significant regions of grey matter loss occurs in the thalami, which abut the midline. What is not known is whether these are neurodevelopmental in origin well prior to symptomatic onset. We aimed to examine other markers of midline developmental anomalies in adults with NPC. METHOD: We examined the size of adhesio interthalamica (AI) and cavum septum pellucidum (CSP) (if present) in nine individuals diagnosed with NPC and nine healthy comparison subjects, matched for age and gender, using a 3T magnetic resonance volumetric sequence and measured the length of the AI and CSP in mm. RESULTS: We found that 5/9 NPC patients and 0/9 controls had a missing AI. AI length was significantly shorter in the patient group. No subject in other group had a large CSP, and CSP length did not differ. Duration of illness showed a trend to a negative correlation with AI length in patients. CONCLUSIONS: Our findings suggest that adult NPC patients show some markers of early neurodevelopmental disturbance, matching findings seen in psychotic disorders. The differences in AI, but not CSP, suggest neurodevelopmental change may occur early in gestation rather than post-partum. The relationship with duration of illness suggests that there may be atrophy over time in these structures, consistent with prior analyses of grey matter regions in NPC.

18.
Cereb Cortex ; 31(5): 2416-2424, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33341873

RESUMO

Reduced amplitude of duration mismatch negativity (dMMN) has been reported in psychotic disorders and at-risk mental state (ARMS); however, few longitudinal MMN studies have examined the amplitude changes during the course of psychosis. We compared dMMN amplitude between ARMS individuals with later psychosis onset and those without, and we longitudinally examined potential dMMN changes around psychosis onset. Thirty-nine ARMS subjects and 22 healthy controls participated in this study. Of the 39 ARMS subjects, 11 transitioned to psychosis (at-risk mental state with later psychosis onset [ARMS-P]) during follow-up and 28 did not (at-risk mental state without later psychosis onset [ARMS-NP]). dMMN was measured twice using an auditory oddball paradigm with a mean interval of 2 years. Follow-up dMMN data were available for all but four ARMS-P subjects. dMMN amplitude at baseline was smaller in ARMS-P subjects compared with control and ARMS-NP subjects. Additionally, ARMS-P subjects displayed a longitudinal decline in dMMN amplitude, which was not present in control and ARMS-P subjects. We also observed a progressive decline in dMMN amplitude during the transition period, suggesting dynamic brain changes associated with the psychosis onset. Our findings implicate dMMN amplitude as a biological predictor of future psychosis onset in high-risk individuals, which may be used for early detection and intervention of psychosis.


Assuntos
Sintomas Prodrômicos , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Adolescente , Adulto , Atenção/fisiologia , Estudos de Casos e Controles , Progressão da Doença , Eletroencefalografia , Feminino , Humanos , Estudos Longitudinais , Masculino , Esquizofrenia Paranoide/fisiopatologia , Adulto Jovem
19.
BMC Psychiatry ; 22(1): 227, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361170

RESUMO

BACKGROUND: Patients with schizophrenia are unaware of their cognitive impairments. Misperception of cognitive impairment is an important factor associated with real-world functional outcomes in patients with schizophrenia. The patient's family member plays a crucial role in detecting patients' cognitive impairments when the patients are unaware of their own cognitive impairments. Previous studies have reported that not only the patient's subjective rating, but also the patient's family members' rating of their cognitive impairment may not be precise. However, it is unclear why family ratings are inaccurate, and which factors impact family ratings. This study investigated whether family ratings differed significantly from the patients' subjective ratings of the patients' cognitive impairments and sought to determine the reason for the differences between the family ratings and the patients' neurocognitive performances. We investigated the relationship between patients' subjective ratings, family ratings for patients' cognitive impairments, neuropsychological performance, and other aspects, including premorbid IQ and clinical symptoms. METHOD: We evaluated 44 patients with schizophrenia for cognitive function using neuropsychological tests; in addition, both the patients and their families rated the patients' cognitive impairments through questionnaires. We used the Mann-Whitney U test to examine whether the family ratings differed significantly from the patients' self-reported ratings of their cognitive impairment. We conducted multiple regression analysis and structural equation modeling to determine why the patients' subjective ratings and the family ratings were not definitively associated with the patients' neurocognitive performances. We performed multiple regression analysis with a stepwise method with neurocognitive performance, premorbid IQ, positive symptoms, and negative symptoms as independent variables and family ratings of patients' cognitive impairments as dependent variables. RESULTS: We found that the family ratings differed significantly from the patients' subjective self-reported ratings of their cognitive impairments. Our results showed that the premorbid IQ of patients is the strongest predictor of family ratings. Furthermore, among the neurocognitive domains, only the processing speed of patients was associated with family ratings. CONCLUSIONS: We found that the family ratings were not consistent with the patients' subjective self-reported ratings and the family ratings were most affected by the patients' premorbid intellectual abilities. These results suggest that the families' current assessments of the patients' current cognitive impairments were affected by the patients' premorbid intellectual ability rather than the patients' current neurocognitive performance. Patients' processing speed predicted family ratings; however, family members' ratings were not related to verbal learning/memory, executive function, and language of patients. Therefore, our findings highlight that patients' family ratings may differ from patients' subjective ratings, results of performance-based neuropsychological tests, and clinician ratings.


Assuntos
Disfunção Cognitiva , Esquizofrenia , Cognição , Disfunção Cognitiva/complicações , Disfunção Cognitiva/diagnóstico , Estudos Transversais , Humanos , Esquizofrenia/complicações , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico
20.
Int J Mol Sci ; 23(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35269625

RESUMO

Specialist bacteria can synthesize nanoparticles from various metal ions in solution. Metal recovery with high efficiency can be achieved by metal-tolerant microorganisms that proliferate in a concentrated metal solution. In this study, we isolated bacteria (Pseudomonas sp. strain KKY-29) from a bacterial library collected from water near an abandoned mine in Komatsu City, Ishikawa Prefecture, Japan. KKY-29 was maintained in nutrient medium with lead acetate and synthesized hydrocerussite and pyromorphite nanoparticles inside the cell; KKY-29 also survived nanoparticle synthesis. Quantitative PCR analysis of genes related to phosphate metabolism showed that KKY-29 decomposed organic phosphorus to synthesize lead phosphate. KKY-29 also deposited various metal ions and synthesized metal nanoparticles when incubated in various metal salt solutions other than lead. The present study considers the development of biotechnology to recover lead as an economically valuable material.


Assuntos
Bactérias , Água Doce , Bactérias/metabolismo , Biodegradação Ambiental , Chumbo , Fósforo/metabolismo
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