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1.
Langmuir ; 40(10): 5508-5517, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38408020

RESUMEN

The droplet transfer across an interface in a microchannel is extensively utilized in diverse fields; however, it is challenging to drive droplets to penetrate the interface at such a small scale. In this study, a novel flow pattern of droplet transfer is observed and the mechanism is investigated; accordingly, an accurate prediction equation for determining the critical condition of droplet transfer is proposed. Meanwhile, the liquid film entrainment is also observed, which leads to the formation of an oil-in-water-in-water system. This study serves as a valuable reference for further studies on the mechanism of droplet transfer and provides practical guidance for its industrial application.

2.
Langmuir ; 39(6): 2218-2232, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36724386

RESUMEN

Fluids containing polymers are frequently utilized in the chemical industry and exhibit shear-thinning characteristics. The flow distribution of non-Newtonian fluids in parallelized microchannels is a key issue to be solved during numbering-up. Numbering-up means increasing the number of parallelized microchannels. In this study, a high-speed camera is used to explore the distribution of fluid flow as well as the uniformity and stability of droplets in conceptual asymmetrical parallelized microchannels. Cyclohexane and carboxymethylcellulose sodium (CMC) aqueous solutions are used as the continuous phase and dispersed phase, respectively. The effects of fluctuation of pressure difference around the T-junction, the hydrodynamic resistance in microchannels, and the shear-thinning property of fluids on flow distribution and droplet formation are revealed. The uniformity and stability of droplets in microdevices with various cavity settings are compared, and an optimal configuration is proposed. Finally, prediction models for the flow distribution of shear-thinning fluids in asymmetrical parallelized microchannels are established.

3.
J Nerv Ment Dis ; 210(12): 935-942, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36044660

RESUMEN

ABSTRACT: This study aims to investigate the relationship between trait anxiety and mental resilience in marathoners and the general population. The study recruited 135 marathoners and 140 members of the general population. Trait anxiety and mental resilience were measured by the State-Trait Anxiety Scale and the Chinese version of the Connor-Davidson Resilience Scale. The amount of weekly exercise resulted in significant differences in the trait anxiety ( F = 6.358, p < 0.01) and mental resilience ( F = 5.996, p < 0.05) levels of the general population and marathoners. Age led to a significant difference in the trait anxiety of marathoners ( F = 10.890, p < 0.01). The half marathoners' daily exercise program is most suitable for the general population for reducing trait anxiety level and increasing mental resilience. Furthermore, marathoners showed lower trait anxiety and higher mental resilience. Therefore, long-term marathon adherence can help improve mental health.


Asunto(s)
Ansiedad , Resiliencia Psicológica , Humanos , Ansiedad/psicología , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/terapia , Encuestas y Cuestionarios , Salud Mental , China/epidemiología
4.
J Nerv Ment Dis ; 210(7): 541-546, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35766547

RESUMEN

ABSTRACT: Psychiatric disorders (depression/anxiety) and sleep quality are linked to coronary artery disease (CAD). CAD patients often complain of various physical symptoms (PSs), which are not only organic changes of biological origin, but also somatization of mental illness. PSs also affect CAD progression. However, the relationship between psychiatric disorders/sleep quality and PS in CAD is less studied, which this study aims to clarify. This cross-sectional observational study was conducted on the first 305 CAD patients diagnosed with PS by Patient Health Questionnaire-15. They were compared with 521 other CAD patients showing no PS. On multivariate analysis, sex, age, family history, psychiatric disorders, and sleep quality were the significant independent predictors of PS. A significant correlation was found between PS severity and the severity of both psychiatric disorders and sleep quality. Further studies are warranted to explore the impact of psychological and sleep intervention on PS and long-term outcomes.


Asunto(s)
Enfermedad de la Arteria Coronaria , Trastornos Mentales , Trastornos del Sueño-Vigilia , Ansiedad , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/psicología , Estudios Transversales , Depresión , Humanos , Trastornos Mentales/epidemiología , Trastornos Mentales/etiología , Calidad del Sueño , Trastornos del Sueño-Vigilia/epidemiología , Trastornos del Sueño-Vigilia/etiología , Encuestas y Cuestionarios
5.
BMC Endocr Disord ; 21(1): 39, 2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33663458

RESUMEN

BACKGROUND: Recently, the relationship between thyroid hormones (THs) across the euthyroid ranges and metabolic syndrome (MetS) has been widely discussed. This study aimed to present specific cutoff values of THs to assess the association between THs and MetS in a euthyroid cohort. METHODS: Data of 2694 subjects, aged 18-80 years, who attended health examination in Xi'an Electric Power Central Hospital from April 2011 to December 2015 were collected and analyzed. The first cohort enrolled 929 participants (followed up by 2221 person-years totally) to assess correlations between serum thyrotropin (TSH), triiodothyronine (T3), thyroxine (T4) levels and MetS. The second cohort included 698 participants (followed up by 1709 person-years totally) to evaluate relationships between serum free triiodothyronine (FT3), free thyroxine (FT4) levels and MetS. MetS was defined according to the criteria of the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) scientific statements of 2009. Euthyroidism was defined as serum TSH, FT3 and FT4 levels within the reference ranges without taking any thyroid medication. RESULTS: The cutoff values for TSH, T3, T4, FT3 and FT4 were 2.0mIU/L, 1.9 nmol/L, 117 nmol/L, 4.3 pmol/L and 16 pmol/L, respectively. Participants were categorized into two groups according to cutoff values: the lower-THs group and the higher-THs group. There was no significant difference in the risk of MetS between two groups in TSH, T3, T4 and FT3. The incidence of MetS was significantly higher in lower-FT4 group than higher-FT4 group (1.00 vs 0.622 (0.458, 0.846), P = 0.002). The lower-FT4/higher-TSH group had the highest hazard ratios of MetS. (2.131vs 1.0 (1.380,3.291), P = 0.006). CONCLUSIONS: Lower normal FT4 (FT4 ≤ 16.0 pmol/L) is an independent risk factor for MetS, and lower normal thyroid function (TSH > 2.0 mIU/L and FT4 ≤ 16.0 pmol/L) is associated with a higher risk of developing MetS.


Asunto(s)
Síndrome Metabólico/sangre , Síndrome Metabólico/epidemiología , Vigilancia de la Población , Tiroxina/sangre , Adulto , Anciano , China/epidemiología , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Síndrome Metabólico/diagnóstico , Persona de Mediana Edad , Vigilancia de la Población/métodos , Estudios Retrospectivos , Factores de Riesgo , Hormonas Tiroideas/sangre
6.
Endocr J ; 68(9): 1043-1056, 2021 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-33883332

RESUMEN

The association between subclinical hypothyroidism (SCH) and metabolic syndrome (MetS) has been widely discussed. This study aimed to conduct an update and comprehensive meta-analysis to reveal the risk of MetS and its components in SCH. PubMed, Embase and ISI Web of Knowledge were searched to identify relevant studies through February 20th, 2020. Review Manager 5.3 and Stata 14.0 were used to conduct the meta-analysis. Both fixed-effects and random-effects models were used. In total, 18 articles (19 studies) incorporating 79,727 participants were included. The pooled OR for MetS comparing subjects with SCH with euthyroid subjects was 1.28 (95% CI: 1.19 to 1.39, p = 0.04, I2 = 40%). Subgroup analysis results showed significant associations of SCH and MetS in the adult subgroup (OR = 1.28, 95% CI: 1.18-1.40), Asian population subgroup (OR = 1.30, 95% CI: 1.19-1.42) and cross-sectional study design subgroup (OR = 1.31, 95% CI: 1.16-1.47). Significant associations of SCH and MetS also existed in all MetS definition criteria subgroups except the Chinese Diabetes Society (CDS) subgroup. SCH was correlated with MetS and was not affected by the subgroup analysis stratified by the proportion of females in the total population, the TSH cutoff value in SCH diagnostic criteria, or the adjustment for confounding factors. SCH was identified to be associated with an increased risk of obesity, hypertension, high triglyceride (TG) levels and low high-density lipoprotein cholesterol (HDL-C) levels. In conclusion, SCH is significantly associated with an increased risk of MetS and four out of five components of MetS.


Asunto(s)
Hipotiroidismo/epidemiología , Síndrome Metabólico/epidemiología , Adolescente , Adulto , Femenino , Humanos , Hipertensión/epidemiología , Hipertrigliceridemia/epidemiología , Hipotiroidismo/sangre , Masculino , Obesidad/epidemiología , Estudios Observacionales como Asunto , Oportunidad Relativa , Factores de Riesgo , Tirotropina/sangre
7.
Pak J Med Sci ; 37(4): 952-958, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34290765

RESUMEN

OBJECTIVES: To evaluate the clinical significance of individualized nutritional formulas on inflammatory factors, immune status and gastrointestinal tolerance in patients with severe head injury. METHODS: A total of 80 patients with severe head injury who were hospitalized in Baoding No.1 Central Hospital from March 2017 to March 2020 were randomly divided into two groups with 40 cases in each group. Patients in both groups were given enteral nutrition (EN), the control group was given conventional enteral nutrition formula through nasointestinal tube, and the experimental group was given individualized nutrition formula. All patients were tested for tumor necrosis factor(TNF-α), C-reactive protein(CRP), interleukin 6(IL-6), IgA, IgM, IgG, serum intestinal fatty acid binding protein(I-FABP) and D-lactic acid concentration before and after enteral nutrition treatment. The incidence of adverse reactions such as abdominal distension, diarrhea, constipation, and gastric retention within seven days after treatment of two groups were compared and analyzed. RESULTS: There was no significant difference in inflammatory factors such as TNF-a, CRP, IL-6, immunoglobulin levels, I-FABP and D-lactic acid concentration between the two groups before treatment (p>0.05). After treatment, the above indicators of the two groups of patients were better than before treatment, the difference was statistically significant (p<0.05), and the experimental group was significantly better than the control group (p<0.05). The experimental group had a gastrointestinal adverse reaction rate of 10%, and the control group had 27.5%, the difference was statistically significant (p=0.04). CONCLUSIONS: Individualized nutritional formula has more significant advantages than conventional nutritional formula for patients with severe head injury, which can reduce inflammatory response, increase the patient's immune level, improve the intestinal mucosal barrier function, have good gastrointestinal tolerance, and have a low incidence of adverse reactions.

8.
Int J Dev Neurosci ; 84(4): 342-348, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38590219

RESUMEN

BACKGROUND: The current study reported a case with a history of neuroradiculitis. Within 2 months of the COVID-19 vaccine, critical Guillain-Barre Syndrome (GBS) appeared after acute diarrhea, progressive myasthenia, and sudden respiratory and cardiac symptoms. METHODS: The syndrome was addressed with measures, such as endotracheal intubation and cardiopulmonary resuscitation vasoactive drugs. Next, we conducted six cycles of human immunoglobulin treatment (dose of 400 mg/kg·d intravenously for 5 days consecutively) and three times plasma exchange (PE, 30 ml/kg), followed by methylprednisolone sodium succinate. Rehabilitation training was carried out continuously. RESULTS: The consciousness of the patient returned to normal, wherein he carried out normal communication. The muscle strength recovered gradually but still could not stand independently. Presently, he is recovering at home. CONCLUSIONS: For patients with previous radiculitis, COVID-19 vaccination may increase the susceptibility to GBS. Thus, it is recommended to extend the vaccination interval for these patients and ensure that any potential increased risk is continually assessed.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Síndrome de Guillain-Barré , Humanos , Síndrome de Guillain-Barré/terapia , Síndrome de Guillain-Barré/etiología , Masculino , COVID-19/complicaciones , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Intercambio Plasmático , Persona de Mediana Edad , Inmunoglobulinas Intravenosas/uso terapéutico , SARS-CoV-2
9.
Clin Chim Acta ; 565: 119997, 2024 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-39401654

RESUMEN

OBJECTIVE: To assess the frequency of lymphocyte subsets and other laboratory indicators in paired cerebrospinal fluid (CSF) and peripheral blood (PB) samples from critically ill patients with intracerebral hemorrhage (ICH) who developed systemic inflammatory response syndrome (SIRS) following surgery. INTRODUCTION: Neuroinflammation and systemic inflammatory responses significantly contribute to secondary brain injury following ICH. Post-surgery SIRS is known to worsen clinical outcomes in ICH patients; however, the immune response in the CSF and PB has not been fully characterized. Understanding immunological changes in ICH patients with SIRS could lead to improved clinical management and prognostic outcomes. METHODS: This study involved a retrospective analysis of data from patients with ICH who underwent surgery in the Neurological Intensive Care Unit (NICU) of Baoding No. 1 Hospital, Hebei Province, China, between January and July 2022. Patients were divided into SIRS and non-SIRS groups based on the clinical criteria. Demographic, clinical, and laboratory data, including lymphocyte subsets in CSF and PB, were collected and analyzed. This study compared lymphocyte subsets and other inflammatory markers between the SIRS and non-SIRS groups. RESULTS: Patients with SIRS demonstrated higher systolic blood pressure (SBP) at admission, worse 90-day prognoses, elevated inflammatory markers, increased levels of complement proteins C3 and C4, and lower levels of immunoglobulin G (IgG) compared to patients without SIRS. Between 3-6 days post-surgery, SIRS patients showed higher percentages of CD3+T cells, CD4+T cells, and CD4+/CD8+ ratios in the CSF than non-SIRS patients. CD3+T cell percentages in the CSF were consistently higher than those in the PB and were independent of PB levels. In contrast, CD3-CD16+CD56+ natural killer (NK) cell percentages were lower in patients with SIRS. No significant differences in PB lymphocyte subsets were found between the two groups. A high CSF CD3+T cell percentage (≥85.68 %) was identified as the strongest predictor of critical ICH with SIRS after surgery, with an appropriate use criterion (AUC) of 0.7742, sensitivity of 77.42 %, specificity of 76.19 %, and 95 % CI of 0.6655-0.8829 (P < 0.0001). CONCLUSION: Elevated levels of CD3+T lymphocytes in CSF are strongly associated with an increased risk of severe cerebral hemorrhage and SIRS following surgery. These findings suggest that monitoring CSF immune markers, particularly CD3+T lymphocytes, could serve as valuable predictors for the development of SIRS in critically ill ICH patients and inform post-surgical treatment strategies.

10.
Int J Immunopathol Pharmacol ; 37: 3946320231207350, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37853743

RESUMEN

Background: The immune inflammatory reaction has vital function in pathologic mechanism of critical intracerebral hemorrhage. It recently has been reported that CD4/CD8 ratio may represent a novel composite immune inflammatory marker to predict prognosis of critical intracerebral hemorrhage (ICH). Nevertheless, as for considering the effects of surgical evacuation upon initiation of immune inflammatory reactions, the association between cerebrospinal fluid (CSF) CD4/CD8 ratio and 60-day functional outcome of patients with critical ICH after surgery has not been investigated. Present study aimed to evaluate the predictive value concerning postoperative complement system and immunoglobulin, paired cerebrospinal fluid and peripheral blood lymphocyte subsets, as well as inflammation index before and after the operations upon the 60-day prognosis of patients with ICH.Methods: In total, 69 patients with acute critical ICH admitted in First Central Hospital of Baoding City from January to July in 2022 were prospectively enrolled. We recorded and analyzed the relevant clinical data. Laboratory parameters included postoperative lymphocyte subsets in paired cerebrospinal fluid and peripheral blood, inflammation index before and after operation. The associations between 60-day outcome and laboratory biomarkers were assessed by multivariable logistic regression analysis. Comparisons of predictive value regarding independent predictors was evaluated by receiver operating characteristic (ROC) curves.Results: In total, 51 patients with critical ICH exhibited poor outcomes at 60 days, which was associated with fever after surgery, hernia before surgery, SAH and lower Glasgow Coma Scale (GCS) at admission and large hematoma volume, greater CD3T%CSF, greater CD4T%CSF, and greater CD4/CD8 ratioCSF. CD4/CD8ratio CSF showcased significant predictive power by comparing with other laboratorial variables (AUC = 0.6808; cut-off = 1.61; sensitivity = 80.39%; specificity = 61.11%; 95% CI: 0.5232-0.8385; p = .0233), which was found to correlated linearly with postoperative fever, first CSF test time, CD3T% CSF, CD4T% CSF, CD8T% CSF, NKCSF, CD3T%PB, CD8T%PB, CD4/CD8 ratioPB, and glucoseCSF. Poor outcome at 60 days linearly correlated with CD4/CD8ratioCSF after adjustments. In 3-5 days after surgery tested CSF lymphocyte subsets, CD4/CD8ratioCSF ≥1.61 was associated with a higher risk for 60-day poor outcome comparing with corresponding subgroups.Conclusions: In association of critical ICH patient prognosis, CSF CD4/CD8 ratio, especially in 3-5 days after surgery, exhibited potential independent predictive ability for 60-day functional outcomes of patients with critical ICH.


Asunto(s)
Linfocitos T CD8-positivos , Hemorragia Cerebral , Humanos , Hemorragia Cerebral/cirugía , Relación CD4-CD8 , Pronóstico , Biomarcadores , Linfocitos T CD8-positivos/patología , Linfocitos T CD4-Positivos/patología , Inflamación
11.
Front Bioeng Biotechnol ; 11: 1215466, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37720320

RESUMEN

The rapid diagnosis of pathogenic infections plays a vital role in disease prevention, control, and public health safety. Recombinase-aided amplification (RAA) is an innovative isothermal nucleic acid amplification technology capable of fast DNA or RNA amplification at low temperatures. RAA offers advantages such as simplicity, speed, precision, energy efficiency, and convenient operation. This technology relies on four essential components: recombinase, single-stranded DNA-binding protein (SSB), DNA polymerase, and deoxyribonucleoside triphosphates, which collectively replace the laborious thermal cycling process of traditional polymerase chain reaction (PCR). In recent years, the CRISPR-Cas (clustered regularly interspaced short palindromic repeats-associated proteins) system, a groundbreaking genome engineering tool, has garnered widespread attention across biotechnology, agriculture, and medicine. Increasingly, researchers have integrated the recombinase polymerase amplification system (or RAA system) with CRISPR technology, enabling more convenient and intuitive determination of detection results. This integration has significantly expanded the application of RAA in pathogen detection. The step-by-step operation of these two systems has been successfully employed for molecular diagnosis of pathogenic microbes, while the single-tube one-step method holds promise for efficient pathogen detection. This paper provides a comprehensive review of RAA combined with CRISPR-Cas and its applications in pathogen detection, aiming to serve as a valuable reference for further research in related fields.

12.
Zookeys ; 980: 43-55, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33192137

RESUMEN

The present study describes a new Lithobiomorpha subgenus, Lithobius (Sinuispineus)subgen. nov., and two new species, L. (Sinuispineus) sinuispineussp. nov. and L. (Sinuispineus) minuticornissp. nov. from China. The representatives of the new subgenus are characterized by a considerable sexual dimorphism of the ultimate leg pair 15, having the femur and tibia unusually enlarged in males, and the dorsal side of the femur with curved posterior spurs. These features distinguish Lithobius (Sinuispineus)subgen. nov. from all other subgenera of Lithobius. The diagnosis and the main morphological characters of the new subgenus and of the two new species are given for both male and female specimens.

14.
Phys Rev E ; 100(3-1): 033112, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31639928

RESUMEN

The initial coalescence of a pendant drop at bulk liquid was jointly investigated by an ultrahigh-speed DC electrical device, a high-speed camera, and a fast micro-Particle Image Velocimetry (micro-PIV). Extended to highly viscous non-Newtonian liquids, the variation of the coalescing width vs time confirms the distinct regimes reported for drop-drop configuration: linear in the inertially limited viscous regime; square root in the inertial regime; possibly a transient viscous regime in between with a logarithmic correction. The measured flow fields during coalescence reveal the transformation of surface energy to kinetic energy, so that the highly located inertia could play a dominant role in relation to the viscous force.

15.
Phys Rev E ; 93(2): 022802, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26986389

RESUMEN

The gas-liquid interfacial dynamics of bubble breakup in a T junction was investigated. Four regimes were observed for a bubble passing through the T junction. It was identified by the stop flow that a critical width of the bubble neck existed: if the minimum width of the bubble neck was less than the critical value, the breakup was irreversible and fast; while if the minimum width of the bubble neck was larger than the critical value, the breakup was reversible and slow. The fast breakup was driven by the surface tension and liquid inertia and is independent of the operating conditions. The minimum width of the bubble neck could be scaled with the remaining time as a power law with an exponent of 0.22 in the beginning and of 0.5 approaching the final fast pinch-off. The slow breakup was driven by the continuous phase and the gas-liquid interface was in the equilibrium stage. Before the appearance of the tunnel, the width of the depression region could be scaled with the time as a power law with an exponent of 0.75; while after that, the width of the depression was a logarithmic function with the time.

16.
FEBS J ; 272(14): 3733-42, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16008571

RESUMEN

The Drosophila melanogaster deoxyribonucleoside kinase (Dm-dNK) double mutant N45D/N64D was identified during a previous directed evolution study. This mutant enzyme had a decreased activity towards the natural substrates and decreased feedback inhibition with dTTP, whereas the activity with 3'-modified nucleoside analogs like 3'-azidothymidine (AZT) was nearly unchanged. Here, we identify the mutation N64D as being responsible for these changes. Furthermore, we crystallized the mutant enzyme in the presence of one of its substrates, thymidine, and the feedback inhibitor, dTTP. The introduction of the charged Asp residue appears to destabilize the LID region (residues 167-176) of the enzyme by electrostatic repulsion and no hydrogen bond to the 3'-OH is made in the substrate complex by Glu172 of the LID region. This provides a binding space for more bulky 3'-substituents like the azido group in AZT but influences negatively the interactions between Dm-dNK, substrates and feedback inhibitors based on deoxyribose. The detailed picture of the structure-function relationship provides an improved background for future development of novel mutant suicide genes for Dm-dNK-mediated gene therapy.


Asunto(s)
Asparagina/genética , Ácido Aspártico/genética , Drosophila melanogaster/enzimología , Drosophila melanogaster/genética , Mutación/genética , Fosfotransferasas (Aceptor de Grupo Alcohol)/química , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Animales , Asparagina/metabolismo , Ácido Aspártico/metabolismo , Cristalografía por Rayos X , Cinética , Modelos Moleculares , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Estructura Terciaria de Proteína , Especificidad por Sustrato , Nucleótidos de Timina/farmacología
17.
Proc Natl Acad Sci U S A ; 101(52): 17970-5, 2004 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-15611477

RESUMEN

Cytosolic thymidine kinase 1, TK1, is a well known cell-cycle-regulated enzyme of importance in nucleotide metabolism as well as an activator of antiviral and anticancer drugs such as 3'-azido-3'-deoxythymidine (AZT). We have now determined the structures of the TK1 family, the human and Ureaplasma urealyticum enzymes, in complex with the feedback inhibitor dTTP. The TK1s have a tetrameric structure in which each subunit contains an alpha/beta-domain that is similar to ATPase domains of members of the RecA structural family and a domain containing a structural zinc. The zinc ion connects beta-structures at the root of a beta-ribbon that forms a stem that widens to a lasso-type loop. The thymidine of dTTP is hydrogen-bonded to main-chain atoms predominantly coming from the lasso loop. This binding is in contrast to other deoxyribonucleoside kinases where specific interactions occur with side chains. The TK1 structure differs fundamentally from the structures of the other deoxyribonucleoside kinases, indicating a different evolutionary origin.


Asunto(s)
Mycoplasma/enzimología , Timidina Quinasa/química , Secuencia de Aminoácidos , Antimetabolitos/farmacología , Sitios de Unión , Cristalización , Desoxirribonucleósidos/química , Evolución Molecular , Humanos , Enlace de Hidrógeno , Iones , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica , Conformación Proteica , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Homología de Secuencia de Aminoácido , Especificidad por Sustrato , Nucleótidos de Timina/química , Ureaplasma urealyticum/enzimología , Zidovudina/farmacología , Zinc/química
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