Thinking more wisely: using the Socratic method to develop critical thinking skills amongst healthcare students.

BACKGROUND: In medicine, critical thinking is required for managing and tolerating medical uncertainty, as well as solving professional problems and treating diseases. However, the core of Confucianism, teacher-centered and exam-oriented settings in middle and high school education may pose challenges to developing critical thinking in Han Chinese or Taiwanese students. Students may be adversely affected by these pedagogies since student-centered settings were more effective in stimulating their critical and reflective thinking, as well as a sense of responsibility, in the ever-changing world. Therefore, guiding students with less stable foundations of critical thinking might require a different approach. A review article highlighted the potential utility of the Socratic method as a tool for teaching critical thinking in the healthcare field. The method involves posing a series of questions to students. More importantly, medical students and residents in clinical teaching are familiar with the method. Almost all healthcare students must complete a biochemistry laboratory course as part of their basic science training. Thus, we aimed to train students to develop critical thinking in the biochemistry laboratory course by using learning sheets and teacher guidance based on the Socratic method and questioning. METHOD: We recruited second-year students from a medical school, of whom 32 had medical science and biotechnology majors (MSB), 27 had pharmaceutical science majors (PS), and 85 were medical undergraduate (MU) students. An exercise in critical thinking was conducted during a biochemistry laboratory course, which consisted of five different biochemical experiments, along with learning sheets that contained three or four critical thinking questions. Then, the teacher evaluated the students' ability to think critically based on nine intellectual dimensions (clarity, accuracy, precision, relevance, depth, breadth, logic, fairness, and significance) based on the universal intellectual standards developed by Prof. Linda Elder and Richard Paul. In the following analysis, regression models and multivariate analysis were used to determine how students improved over time, and trajectory analysis were carried out in order to observe the trends in students' critical thinking skills construction. RESULTS: Clarity and logic dimensions were identified as the key elements to facilitate the development of critical thinking skills through learning sheets and teacher guidance in students across all three different healthcare majors. The results showed that metacognitive monitoring via Socratic questioning learning sheets have demonstrated potential encourage students to develop critical thinking skills in all dimensions. Another unique contribution of current study was present the heterogeneous learning patterns and progress trajectories of clarity and logic dimensions within classes. CONCLUSION: Using the Socratic learning model could effectively develop students' critical thinking skills so they can more effectively care for their patients.

Profiling antibody signature of schizophrenia by Escherichia coli proteome microarrays.

Schizophrenia (SZ) is influenced by genetic and environmental factors, and associated with chronic neuroinflammation. If the symptoms express after adolescence, environmental impacts are more substantial, and the disease is defined as adult-onset schizophrenia (AOS). Effects of environmental factors on antibody responses such as Escherichia coli (E. coli) to immunoglobulin G (IgG) and immunoglobulin M (IgM) might increase the severity of symptoms in SZ via the gut-brain axis. The purpose of this study is to reveal antibody profiles of SZ against bacterial protein antigens. We analyzed the IgG and IgM antibodies using E. coli proteome microarrays from 80 SZ patients and 40 healthy controls (HC). Using support vector machine to select panels of proteins differentiating between groups and conducted enrichment analysis for those proteins. We identified that the groL, pldA, yjjU, livG, and ftsE can classify IgGs in AOS vs HC achieved accuracy of 0.7. The protein yjjU, livG and ftsE can form the best combination panel to classify IgG in AOS vs HC with accuracy of 0.8. The enrichment results are highly related to ABC (ATP binding cassette) transporter in the protein domain and cellular component. We further found that the human ATP binding cassette subfamily b member 1 (ABCB1) autoantibody level in AOS is significantly higher than in HC. The findings suggest that AOS had different immunoglobulin production compared to early-onset schizophrenia (EOS) and HC. We also identified potential antibody biomarkers of AOS and found their antigens are enriched in ABC transporter related domains, including human ABCB1 protein.

Neurodevelopment regulators miR-137 and miR-34 family as biomarkers for early and adult onset schizophrenia.

Early-onset schizophrenia (EOS) may have stronger familial aggregation and a more severe outcome than adult-onset schizophrenia (AOS). MicroRNA (miRNA) takes on dual roles as a genetic and epigenetic modulator, which may mediate the influence of genetic risk. Neurological soft signs (NSS) are neurological abnormalities that may be intermediate phenotypes or endophenotypes for schizophrenia. Our previous study found poorer performance on NSS tests from patients with EOS and their unaffected first-degree relatives. Thus, we aimed to identify a set of aberrant neurodevelopmental-related miRNAs that could serve as potential biomarkers for EOS or schizophrenia with NSS. This study included 215 schizophrenia patients (104 EOS and 111 AOS), 72 unaffected first-degree relatives, 31 patients with bipolar disorder, and 100 healthy controls. Differential expression analysis revealed that miR-137, miR-34b, and miR-34c were significantly up-regulated in patients with schizophrenia and their unaffected first-degree relatives compared to healthy controls. Receiver operating characteristic (ROC) analysis showed that the miR-137 expression signature could be used to discriminate between patients with EOS and healthy controls (AUC = 0.911). Additionally, miR-34b had the highest ability to discriminate between EOS and AOS (AUC = 0.810), which may indicate different aetiological pathways to disease onset. Moreover, miR-137 dysregulation was correlated with almost all NSS subscales (i.e., sensory integration, motor sequencing, etc.) and, when EOS patients with NSS, miR-137 expression discriminated these patients from healthy controls to a greater extent (AUC = 0.957). These findings support the potential for neurodevelopmental-related miRNAs to be used as indicators of vulnerability to EOS.

Risk Model Assessment in Early-Onset and Adult-Onset Schizophrenia Using Neurological Soft Signs.

Age at onset is one of the most important clinical features of schizophrenia that could indicate greater genetic loadings. Neurological soft signs (NSS) are considered as a potential endophenotype for schizophrenia. However, the association between NSS and different age-onset schizophrenia still remains unclear. We aimed to compare risk model in patients with early-onset schizophrenia (EOS) and adult-onset schizophrenia (AOS) with NSS. This study included 262 schizophrenia patients, 177 unaffected first-degree relatives and 243 healthy controls. We estimated the discriminant abilities of NSS models for early-onset schizophrenia (onset age < 20) and adult-onset schizophrenia (onset age ≥ 20) using three data mining methods: artificial neural networks (ANN), decision trees (DT) and logistic regression (LR). We then assessed the magnitude of NSS performance in EOS and AOS families. For the four NSS subscales, the NSS performance were greater in EOS and AOS families compared with healthy individuals. More interestingly, there were significant differences found between patients' families and control group in the four subscales of NSS. These findings support the potential for neurodevelopmental markers to be used as schizophrenia vulnerability indicators. The NSS models had higher discriminant abilities for EOS than for AOS. NSS were more accurate in distinguishing EOS patients from healthy controls compared to AOS patients. Our results support the neurodevelopmental hypothesis that EOS has poorer performance of NSS than AOS. Hence, poorer NSS performance may be imply trait-related NSS feature in EOS.

N-Terminal domain of Bombyx mori fibroin mediates the assembly of silk in response to pH decrease.

Fibroins serve as the major building blocks of silk fiber. As the major component of fibroin, the fibroin heavy chain is a considerably large protein comprising N-terminal and C-terminal hydrophilic domains and 12 highly repetitive Gly-Ala-rich regions flanked by internal hydrophilic blocks. Here, we show the crystal structure of the fibroin N-terminal domain (FibNT) at pH 4.7, revealing a remarkable double-layered anti-parallel ß-sheet with each layer comprising two FibNT molecules entangled together. We also show that FibNT undergoes a pH-responsive conformational transition from random coil to ß-sheets at around pH 6.0. Dynamic light scattering demonstrates that FibNT tends to oligomerize as pH decreases to 6.0, and electron microscopy reveals micelle-like oligomers. Our results are consistent with the micelle assembly model of silk fibroin and, more importantly, show that the N-terminal domain in itself has the capacity to form micelle-like structures in response to pH decrease. Structural and mutagenesis analyses further reveal the important role of conserved acidic residues clustered in FibNT, such as Glu56 and Asp100, in preventing premature ß-sheet formation at neutral pH. Collectively, we suggest that FibNT functions as a pH-responsive self-assembly module that could prevent premature ß-sheet formation at neutral pH yet could initiate fibroin assembly as pH decreases along the lumen of the posterior silk gland to the anterior silk gland.

Structure-guided activity restoration of the silkworm glutathione transferase Omega GSTO3-3.

Glutathione transferases (GSTs) are ubiquitous detoxification enzymes that conjugate hydrophobic xenobiotics with reduced glutathione. The silkworm Bombyx mori encodes four isoforms of GST Omega (GSTO), featured with a catalytic cysteine, except that bmGSTO3-3 has an asparagine substitution of this catalytic residue. Here, we determined the 2.20-Å crystal structure of bmGSTO3-3, which shares a typical GST overall structure. However, the extended C-terminal segment that exists in all the four bmGSTOs occupies the G-site of bmGSTO3-3 and makes it unworkable, as shown by the activity assays. Upon mutation of Asn29 to Cys and truncation of the C-terminal segment, the in vitro GST activity of bmGSTO3-3 could be restored. These findings provided structural insights into the activity regulation of GSTOs.

[Quantitative analysis of different restoration stages during natural succession processes of subalpine dark brown coniferous forests in western Sichuan, China].

By adopting space as a substitute for time, and based on the approaches of inter-specific association, PCA and optimal division, the restoration stages of various secondary forest communities originated from the natural succession processes of bamboo-dark brown coniferous and moss-dark brown coniferous old-growth forests after clear-cut were quantified at different temporal series (20, 30, 30, 40, 50 and 160-200 years). The results showed that Betula albo-sinensis, Salix rehderiana, Acer mono, A. laxiflorum, Prunus tatsienensis, Hydrangea xanthoneura, Tilia chinensis and Salix dolia were the declining species groups with progressive restoration processes from secondary forest to mature moss and bamboo-dark brown coniferous forests, Sorbus hupehensis, S. koehneana and P. pilosiuscula were the transient species groups, and Abies faxoniana, Picea purpurea, Tsuga chinensis and P. wilsonii were the progressive species groups. During the period of 20-40 years restoration, the secondary forests were dominated by broad-leaved tree species, such as B. albo-sinensis, and the main forest types were moss--B. albo-sinensis forest and bamboo--B. albo-sinensis forest. Through 50 years natural succession, the secondary forests turned into conifer/broad-leaved mixed forest dominated by B. albo-sinensis and A. faxoniana, and the main forest types were moss--B. albo-sinensis--A. faxoniana forest and bamboo--B. albo-sinensis--A. faxoniana forest. The remained 160-200 years old coniferous forests without cutting were dominated by old-growth stage A. faxoniana, and the main forest types were moss--A. faxoniana forest and bamboo--A. faxoniana forest.

[The relationship between soil respiration and the temperature at different soil depths in subalpine coniferous forest of western Sichuan Province].

By using closed chamber IRGA technique, a continuous measurement of soil respiration rate was conducted in the subalpine natural coniferous forest mainly composed of Abies faxoniana in the eastern edge of Qinghai-Tibet Plateau, with the temperature at different soil depths (0, 5, 10, 15 and 20 cm) measured simultaneously. Base on the measurements, the quantitative relationships between soil respiration rate and the temperature at different soil depths were explored, and the results showed that the soil respiration rate in the forest had remarkable diurnal and seasonal changes, being the highest at 12:00-14:00 and in August, and the lowest at 8:00-10:00 and in November, which were accorded with the dynamics of soil temperature. Soil respiration rate had a significant exponential correlation with the temperature at different soil depths, and the highest correlation occurred at the soil depth of 15 cm (R2 =0.82, P <0.01). The Q10, value at soil depths of 0, 5, 10, 15 and 20 cm was 2. 36, 4.75, 4.90, 6.27 and 5.46, respectively, indicating that the Q10 value of soil respiration tended to be larger at high elevation with low temperature.

[Study on influence of buffer system on separate capacity of macroporous resin on ferulic liposome].

OBJECTIVE: To study the effect of buffer on separate capacity of macroporous resin. To evaluate the quality of ferulic acid liposome and determine its entrapment efficiency. METHOD: Different type of macroporous resin counterpoised by buffer system of Na2 HPO3-NaH2, PO3 was used to separate the free ferulic acid from the preparation and HPLC was used to determine the concentration of the ferulic acid to calculate the entrapment efficiency. RESULT: This method had good linearity in the range of 0.56 - 2.8 g x mL(-1) (r = 0.999 6). The precision RSD was less than 1.1%. The adsorption effect of macroporous resin on liposome was reduced while it had no effect on the absorption ability of macroporous resin on the ferulic acid by the usage of buffer. The recovery of HPD450 resin on blank liposome was between 97.2% - 100.8%, while the average recovery is 98.1%. CONCLUSION: Buffer system can enhance the separate ability of macroporous resin on liposome and free drug.

Urea induced inactivation and unfolding of arginine kinase from the sea cucumber Stichopus japonicus.

Urea titration was used to study the inactivation and unfolding equilibrium of arginine kinase (AK) from the sea cucumber Stichopus japonicus. Both fluorescence spectral and circular dichroism spectral data indicated that an unfolding intermediate of AK existed in the presence of 1.0 to 2.0 M urea. This was further supported by the results of size exclusion chromatography. The spectral data suggested that this unfolding intermediate shared many structural characteristics with the native form of AK including its secondary structure, tertiary structure, as well as its quaternary structure. Furthermore, according to the residual activity curve, this unfolding intermediate form still retained its catalytic function although its activity was lower than that of native AK. Taken together, the results of our study give direct evidence that an intermediate with partial activity exists in unfolding equilibrium states of AK during titration with urea.

Multiple effects of chemical reagent on enzyme: o-phthalaldehyde-induced inactivation, dissociation and partial unfolding of lactate dehydrogenase from pig heart.

The effects of o-phthalaldehyde (OPTA) on lactate dehydrogenase (LDH) have been studied by following changes in enzymatic activity, aggregation state and conformation. Treatment with OPTA resulted in pseudo first-order inactivation of LDH over a wide concentration range of the inhibitor, and the second-order rate constant was estimated to be 1.52M(-1)s(-1). The loss of enzyme activity was concomitant with the increases in absorbance at 337nm and fluorescence intensity at 405nm. Complete loss of enzyme activity was accompanied by the formation of approximately 4mol isoindole derivatives per mole LDH subunit. Cross-linking experiments verified enzyme dissociation during OPTA modification, which could be attributed to the modification of both thiol groups and lysine residues. Circular dichroism (CD) spectra showed that the secondary structure of the OPTA-modified enzyme decreased correspondingly. Comparison of the inactivation with the conformational changes of the enzyme suggests that the active site of the enzyme exhibits greater conformational flexibility than the enzyme molecule as a whole. It is concluded that OPTA modification has multiple effects on LDH, including its inactivation, dissociation and partial unfolding.

Expression, purification, and characterization of arginine kinase from the sea cucumber Stichopus japonicus.

The arginine kinase gene of sea cucumber Stichopus japonicus was cloned and inserted into the prokaryotic expression plasmid pET-21b. The protein was expressed in a soluble and functional form in Escherichia coli and purified by Blue Sepharose CL-6B, DEAE-32, and Sephadex G-100 chromotography with a final yield of 83 mgL(-1) of LB medium. The specific activity, electrophoretic mobility, and isoelectric focusing were all identical with those of arginine kinase that was purified from sea cucumber muscle. The fluorescence emission spectrum of arginine kinase had a maximum fluorescence at a wavelength of 330 nm upon excitation at 295 nm. These results are the first report of this purified protein.

Inactivation and conformational changes of lactate dehydrogenase from porcine heart in sodium dodecyl sulfate solutions.

The inactivation and conformational changes of porcine heart lactate dehydrogenase (LDH) have been studied in sodium dodecyl sulfate (SDS) solutions. Increasing SDS concentration led to a quick and concentration-dependent inhibition of the enzyme, with complete inactivation within 5 min in the presence of 1.0 mM SDS. Meanwhile, fluorescence emission and circular dichroism spectra were used to follow the conformational changes of the enzyme during this process, concurrently showing that SDS less than 1.0 mM induced only limited conformational changes to LDH. The above results are in accordance with the suggestion by Tsou (Trends Biochem. Sci. 11 (1986) 427; Science 262 (1993) 380) that the active site usually be more flexible than the enzyme molecule as a whole. Furthermore, the results of polyacrylamide gel electrophoresis (PAGE) implied that unfolding intermediates were presented in the above process. When the SDS concentration used to treat LDH was increased, the bands of native enzyme on native PAGE faded and finally almost disappeared. Meanwhile, multiple bands with lower mobility but no activity emerged behind and enhanced correspondingly. Fast protein liquid chromatography indicated that dissociation occurred during the course of denaturation. The reasons for the above phenomena have been discussed. It was suggested that SDS, binding to LDH to form different LDH-SDS complexes, conferred an array of different unfolding states over the enzyme, and in turn resulted in the formation of the multiple bands on the native PAGE.