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1.
Front Plant Sci ; 14: 1181311, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37324722

RESUMEN

Plastoglobules (PGs) are plastidial lipid droplets enclosed by a polar monolayer born from the thylakoid membrane when plants require active lipid metabolism, including carotenogenesis, under the environmental stress and during plastid transition. Despite the fact that many proteins are reported to target PGs, their translocation mechanism has remained largely unexplored. To elucidate this process, we studied the influence of three hydrophobic regions (HR)-HR1 (1-45th aa), HR2 (46-80th aa), and HR3 (229-247th aa)-of rice phytoene synthase 2 (OsPSY2, 398 aa), which has previously shown to target PGs. As results, HR1 includes the crucial sequence (31-45th aa) for chloroplast import and the stromal cleavage occurs at a specific alanine site (64th aa) within HR2, verifying that a N-terminal 64-aa-region works as the transit peptide (Tp). HR2 has a weak PG-targeting signal by showing synchronous and asynchronous localization patterns in both PGs and stroma of chloroplasts. HR3 exhibited a strong PG-targeting role with the required positional specificity to prevent potential issues such as non-accumulation, aggregation, and folding errors in proteins. Herein, we characterized a Tp and two transmembrane domains in three HRs of OsPSY2 and propose a spontaneous pathway for its PG-translocation with a shape embedded in the PG-monolayer. Given this subplastidial localization, we suggest six sophisticated tactics for plant biotechnology applications, including metabolic engineering and molecular farming.

2.
Front Plant Sci ; 13: 861036, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35498655

RESUMEN

The methylerythritol 4-phosphate (MEP) pathway is responsible for providing common precursors for the biosynthesis of diverse plastidial terpenoids, including chlorophylls, carotenoids, and phytohormones, in plants. In rice (Oryza sativa), the last-step genes encoding 4-hydroxy-3-methylbut-2-enyl diphosphate reductase [HDR/isoprenoid synthesis H (IspH)] have been annotated in two genes (OsIspH1 and OsIspH2) in the rice genome. The spatial transcript levels indicated that OsIspH1 is highly expressed in all tissues at different developmental stages, whereas OsIspH2 is barely expressed due to an early stop in exon 1 caused by splicing error. OsIspH1 localized into plastids and osisph1, a T-DNA inserted knockout mutant, showed an albino phenotype, indicating that OsIspH1 is the only functional gene. To elucidate the role of OsIspH1 in the MEP pathway, we created two single (H145P and K407R) and double (H145P/K407R) mutations and performed complementation tests in two hdr mutants, including Escherichia coli DLYT1 strains and osisph1 rice plants. The results showed that every single mutation retained HDR function, but a double mutation lost it, proposing that the complementary relations of two residues might be important for enzyme activity but not each residue. When overexpressed in rice plants, the double-mutated gene, OsIspH1MUT , reduced chlorophyll and carotenoid biosynthesis in the leaves and seeds. It confirmed the crucial role of OsIspH1 in plastidic terpenoid biosynthesis, revealing organ-specific differential regulation of OsIspH1 in rice plants.

3.
Pharmaceutics ; 12(12)2020 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-33255298

RESUMEN

Fluvastatin (FLUVA), which is a common anti-hypercholesterolemia drug, exhibits potential anticancer activity as it suppresses the proliferation, angiogenesis, and metastasis of breast cancer cells via inhibiting 3-hydroxy-methyl glutaryl-coenzyme A (HMG-CoA) reductase. In this study, hyaluronan-conjugated FLUVA-encapsulating liposomes (HA-L-FLUVA) were evaluated for their anticancer efficacy in vitro and in vivo. The particle size, zeta potential, and encapsulation efficiency of HA-L-FLUVA were 158.36 ± 1.78 nm, -24.85 ± 6.26 mV, and 35%, respectively. Growth inhibition of breast cancer stem cells (BCSCs) by HA-L-FLUVA was more effective than that by free FLUVA. The half maximal inhibitory concentration (IC50) values of FLUVA, L-FLVUA, and HA-L-FLUVA were 0.16, 0.17, and 0.09 µM, respectively. The in vivo anticancer effect of HA-L-FLUVA in combination with doxorubicin (DOX) was more effective than that of free FLUVA, free DOX, and HA-L-FLUVA. The longest survival of mice was achieved by treatment with FLUVA (15 mg/kg) and HA-L-FLUVA (15 mg/kg) + DOX (3 mg/kg), followed by HA-L-FLUVA (15 mg/kg), Dulbecco's phosphate buffered saline, and DOX (3 mg/kg). No more than 10% body weight loss was observed in the mice injected with FLUVA, indicating that the drug was not toxic. Taken together, these results indicate that HA-L-FLUVA could serve as an effective anticancer drug by inhibiting the growth of both breast cancer cells and cancer stem cells.

4.
Int J Mol Sci ; 21(23)2020 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-33255547

RESUMEN

Most terpenoids are derived from the basic terpene skeletons of geranyl pyrophosphate (GPP, C10), farnesyl-PP (FPP, C15) and geranylgeranyl-PP (GGPP, C20). The trans-prenyltransferases (PTs) mediate the sequential head-to-tail condensation of an isopentenyl-PP (C5) with allylic substrates. The in silico structural comparative analyses of rice trans-PTs with 136 plant trans-PT genes allowed twelve rice PTs to be identified as GGPS_LSU (OsGGPS1), homomeric G(G)PS (OsGPS) and GGPS_SSU-II (OsGRP) in Group I; two solanesyl-PP synthase (OsSPS2 and 3) and two polyprenyl-PP synthases (OsSPS1 and 4) in Group II; and five FPSs (OsFPS1, 2, 3, 4 and 5) in Group III. Additionally, several residues in "three floors" for the chain length and several essential domains for enzymatic activities specifically varied in rice, potentiating evolutionarily rice-specific biochemical functions of twelve trans-PTs. Moreover, expression profiling and localization patterns revealed their functional compartmentation in rice. Taken together, we propose the predicted topology-based working model of rice PTs with corresponding terpene metabolites: GPP/GGPPs mainly in plastoglobuli, SPPs in stroma, PPPs in cytosol, mitochondria and chloroplast and FPPs in cytosol. Our findings could be suitably applied to metabolic engineering for producing functional terpene metabolites in rice systems.


Asunto(s)
Dimetilaliltranstransferasa/ultraestructura , Oryza/ultraestructura , Proteínas de Plantas/ultraestructura , Terpenos/metabolismo , Dimetilaliltranstransferasa/química , Dimetilaliltranstransferasa/genética , Regulación de la Expresión Génica de las Plantas , Oryza/química , Oryza/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Fosfatos de Poliisoprenilo/química , Fosfatos de Poliisoprenilo/metabolismo , Conformación Proteica , Homología Estructural de Proteína , Especificidad por Sustrato
5.
J Back Musculoskelet Rehabil ; 31(6): 1131-1138, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30010099

RESUMEN

BACKGROUND AND OBJECTIVE: Lumbar spinal stenosis (LSS) is a common spinal disorder that causes patients to assume a forward-trunk posture. Spinal alignment affects gait, muscle activity, and trunk-pelvis-limb coordination because the lumbar spine and muscles interact to allow load transfer between the lower back and pelvis during sagittal trunk movement. Therefore, we investigated the relationships among trunk and pelvic movement, swing toe clearance, and muscle coordination (isolated contraction ratios) of the stance limb during obstacle-crossing by patients with LSS. METHODS: Ten patients with LSS and ten control subjects were enrolled. All navigated an obstacle during walking. Kinematic data from the trunk and lower extremities were monitored using a three-dimensional motion analysis system. In addition, we measured the isolated contraction ratios of the gluteus medius (GMed) and vastus lateralis (VL) using surface electromyography. RESULTS: The normalized lead limb distance was significantly lower in the LSS group than in controls. The spine flexion angle when the swinging limb toe was above the obstacle was higher, but the pelvic anterior tilting angle was lower, in the LSS group. LSS patients also had a significantly lower isolated contraction ratio of the GMed in the trailing stance limb but a significantly higher VL. CONCLUSIONS: Patients with LSS adapted a poor posture and their thoracic and spinal regions were hyperflexed with restricted pelvic obliquity. This created an inefficient gait, a shorter leading limb step, and less stable muscle coordination in the stance limb. Our findings may help healthcare professionals manage patients with LSS.


Asunto(s)
Vértebras Lumbares , Músculo Esquelético/fisiopatología , Pelvis/fisiopatología , Estenosis Espinal/diagnóstico , Dedos del Pie/fisiopatología , Torso/fisiopatología , Caminata/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Electromiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Postura , Estenosis Espinal/fisiopatología , Adulto Joven
6.
J Phys Ther Sci ; 29(2): 250-254, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28265151

RESUMEN

[Purpose] The greater trochanter (GT) is an important structure in biomedical research, but the measurement methods require development. This study presents data from a new measurement method that does not use GT-marker-based measurement (No GT-m) in comparison with GT-marker based measurement (GT-m). [Subjects and Methods] We recruited 20 healthy subjects, who were asked to perform and maintain a prone position and then move to the prone hip extension. A motion capture system collected the kinematic data and the location of the GT was calculated by two measurements. [Results] GT migration distance differed significantly between the two measurements and the coefficient of the variation value was lower for the No GT-m method. Thigh lengths of the No GT-m method were comparable to the original lengths. There were significant differences between the GT-m and the other methods. [Conclusions] These data suggest that the GT-m method yielded a lower precision with a smaller GT migration distance. In the comparison of thigh length, the No GT-m method was in close agreement with the original length. We suggest that determining the location of the GT using the No GT-m has greater accuracy than the GT-m method.

7.
J Dermatolog Treat ; 27(6): 510-514, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27121901

RESUMEN

BACKGROUND: A previous 6-month study using a more highly concentrated novel hyaluronic acid (HA) filler, PP-501-B, found nasolabial fold (NLF) improvements with increased tolerability. OBJECTIVE: We investigated the long-term efficacy, durability and safety of PP-501-B in the correction of NLFs. METHODS: Subjects completing the initial six-month study were enrolled in this 24-month, randomized, multicenter, double-blind, split-face, extension study. The injection areas and treatment procedures were identical to those of the initial study: each subject was injected with PP-501-B in one NLF and with Restylane Perlane (Q-med) in the contralateral NLF. We reassessed wrinkle improvement using the five-point Wrinkle Severity Rating Scale (WSRS) and changes in the Global Aesthetic Improvement Scale at 12, 18 and 24 months after the initial treatment. RESULTS: Of the 81 patients enrolled, 72 completed the study. The WSRS score significantly decreased from baseline throughout the follow-up period after retreatment with both fillers. There was no significant difference in the WSRS scores between the two fillers at 24 months. Both fillers were well tolerated with no severe complications or adverse reactions. CONCLUSION: The new HA filler PP-501-B is safe and effective in the long term for the correction of moderate-to-severe NLFs, even after a second treatment.


Asunto(s)
Técnicas Cosméticas , Ácido Hialurónico/administración & dosificación , Surco Nasolabial , Adulto , Técnicas Cosméticas/efectos adversos , Método Doble Ciego , Femenino , Humanos , Ácido Hialurónico/uso terapéutico , Inyecciones , Masculino , Persona de Mediana Edad , Retratamiento
8.
J Phys Ther Sci ; 27(5): 1333-5, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26157213

RESUMEN

[Purpose] To investigate the effects of erect sitting, slouched posture with cross-legged sitting, and erect posture with cross-legged sitting on the lumbar and pelvic angles, and gluteal pressure. [Subjects] For the experiments, 17 healthy women were recruited. [Methods] All subjects were asked to perform three sitting postures: erect sitting, slouched posture with cross-legged sitting, and erect posture with cross-legged sitting. Lumbar and pelvic angles were measured using a three-dimensional motion-capture system, and gluteal pressure was measured using a pressure mat. [Results] Compared to erector sitting, slouched posture with cross-legged sitting showed significantly greater lumbar flexion, posterior pelvic tilt, and left pelvic tilt. Compared to erect sitting, erect posture with cross-legged sitting showed significantly greater lumbar flexion and posterior pelvic tilt. Compared to erect posture with cross-legged sitting, slouched posture with cross-legged sitting showed significantly greater lumbar flexion and posterior pelvic tilt. Compared to erect sitting and erect posture with cross-legged sitting, slouched posture with cross-legged sitting showed significantly greater left gluteal pressure; there was no significant difference in right gluteal pressure. [Conclusion] An erect posture can reduce changes in lumbar and pelvic angles, and gluteal pressure compared to a slouched posture during cross-legged sitting.

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