Waiting for self-healing as a primary management strategy for lower lip mucoceles.

OBJECTIVES: Oral mucoceles are most frequently encountered on the lower lip. A variety of treatment options are currently employed, including surgical excision, pharmacological injections, and laser therapy. However, each of these approaches may introduce risks and potential complications. Clinical practice has demonstrated a potential for self-healing in lower lip mucoceles, making a conservative observational approach more appealing. This research is a prospective study aimed at evaluating the self-healing capacity of lower lip mucoceles. METHODS: In this prospective study, patients with mucoceles were encouraged to intentionally delay medical intervention and to wait for self-healing. Disappearance of the mucocele for at least 3 months was defined as self-healing. RESULTS: Thirty patients with lower lip mucoceles were included. With no intervention, 24 patients (80%) reported self-healing of lower lip mucoceles. The mean natural duration of the mucoceles was 3.63 (± 4.7; 1-24) months. After self-healing of the mucocele, the patients were followed up for 17.21 (± 9.45; 2-30) months and there were no reported recurrences. CONCLUSIONS: Lower lip mucoceles have a high potential for self-healing and patients may be routinely encouraged to wait for self-healing. CLINICAL RELEVANCE: The high self-healing rate observed in this study suggests that a conservative, non-interventional approach might be considered as the first-line management for lower lip mucoceles.

Three new compounds from the twigs and leaves of Nageia fleuryi Hickel.

Two new diterpenoids, 12,15-di-O-acetylhypargenin B (1) and taiwanin F-12-O-ß-D-glucopyranoside (2), one new monoterpenoid, (S)-7-methyl-3-methyleneoct-6-ene-1,2-diyl diacetate (3), together with eight known compounds (4-11), were obtained from the twigs and leaves of Nageia fleuryi Hickel. The structures of the new compounds were elucidated by extensive spectroscopic techniques including HR-ESI-MS and 1 D and 2 D NMR experiments. Spectroscopic data of the known compound 4 were provided for the first time. Compounds 1 and 11 exhibited strong inhibitory activity on LPS-stimulated production of NO in RAW 264.7 murine macrophages, while compounds 1, 3, and 5 showed significant quinone reductase inducing activity in Hepa 1c1c7 murine hepatoma cells. Moreover, compounds 7 and 8 showed inhibitory activity against the proliferation of the human prostate carcinoma DU145 cells.

[Meta-analysis of Bailing Capsules in improvement of microinflammation and nutritional status among maintenance hemodialysis patients].

This Meta-analysis was designed to evaluate the effects of Bailing Capsules on microinflammation and nutritional status of maintenance hemodialysis patients, and to determine its efficacy and safety. The randomized controlled trials concerning the intervention of microinflammation and nutritional status in maintenance hemodialysis patients with Bailing Capsules were searched from Chinese and English databases including CNKI, Wanfang, VIP, PubMed, EMbase, and Cochrane Library. A total of 16 articles were obtained, involving 1 095 cases. As revealed by Meta-analysis,(1)Bailing Capsules lowered the levels of serum high sensitivity C-reactive protein(SMD=-0.92, 95%CI[-1.05,-0.80], P<0.000 01), interleukin-6(SMD=-1.49, 95%CI[-1.96,-1.02], P<0.000 01), and tumor necrosis factor-α(SMD=-1.48, 95%CI[-1.68,-1.28], P<0.000 01) in patients with maintenance hemodialysis, thus alleviating microinflammation.(2)Bailing Capsules elevated the levels of serum hemoglobin(SMD=1.37, 95%CI[1.21, 1.54], P<0.000 01), albumin(SMD=0.78, 95%CI[0.57, 0.98], P<0.000 01), and triglyceride(SMD=0.29, 95%CI[0.07, 0.50], P=0.01) in patients with hemodialysis to improve their nutritional status.(3)Bailing Capsules reduced the incidence of cardiovascular events(RR=0.45, 95%CI[0.34, 0.59], P<0.000 01).(4)A total of six patients presented with mild gastrointestinal discomfort after receiving Bailing Capsules, and no serious adverse reactions were observed. The sequential analysis showed that the sample size of this Meta-analysis had reached the expected value. Meanwhile, the grade of evidence quality suggested that the outcome indicators were mainly low or extremely low in quality. In conclusion, Bailing Capsules might have potential advantages in alleviating microinflammation, improving nutritional status, and reducing the incidence of cardiovascular events. However, in view of the low quality and evidence of the included literature, high-quality clinical trials are needed to further confirm the efficacy and safety of Bailing Capsules.

Network Pharmacology-Based Prediction of Bioactive Compounds and Potential Targets of Wenjing Decoction for Treatment of Endometriosis.

Endometriosis is a chronic estrogen-dependent inflammatory disorder that negatively affects the quality of life in women. The Wenjing decoction (WJD) is a traditional Chinese medicine that has been shown to have a therapeutic effect on endometriosis. Our study systematically explored the mechanism of WJD against endometriosis using a network pharmacology approach. Potentially bioactive compounds of WJD and their possible targets were retrieved from the Traditional Chinese Medicine System Pharmacology Database and Analysis Platform. The protein-protein interaction network and herbs-compounds-genes multinetwork were constructed using Cytoscape for visualization. Subsequently, the signaling pathways of common targets were retrieved from the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, and molecular docking was performed using PyRx software. In total, 48 common targets were screened, such as IL6 and ESR1, which were related to inflammation and the endocrine system. The top five bioactive compounds were quercetin, kaempferol, wogonin, beta-sitosterol, and stigmasterol. KEGG enrichment analysis revealed 65 pathways containing inflammatory- and endocrine-related signaling pathways, such as the "TNF signaling pathway" and the "estrogen signaling pathway." Taken together, the results of our network pharmacology analysis predicted that certain active ingredients of WJD might treat endometriosis by regulating inflammation and/or endocrine, which provided references for further understanding and exploration of WJD on endometriosis.

Primary Reconstruction of Extensive Forehead Defects Using Supraorbital Artery Propeller Perforator Flap.

PURPOSE: Extensive resection of skin carcinomas in the periorbital and forehead regions often results in complicated defects involving the upper eyelid, superciliary arch, and nasal dorsum. The aim of this study is to report our experience with the use of supraorbital artery perforator propeller flaps for primary repair of complicated forehead defects. METHODS: A total of 6 patients underwent carcinoma resection with primary surgical reconstruction using supraorbital propeller flap at the Peking University School and Hospital of Stomatology from December 2015 to December 2018. We describe the technique and retrospectively review the outcomes. RESULTS: A single propeller flap was used in 5 patients and 2 propeller flaps (supraorbital and nasolabial artery propeller flaps) in 1 patient. Two patients developed venous congestion of the flap on the first postoperative day; however, in both cases it was relieved by multiple needle punctures. All flaps had survived well at 1-year follow-up. Five patients had a normal eyelid closure, but 1 patient presented with lagophthalmos, which required correction by secondary surgery. CONCLUSIONS: Propeller flap based on the supraorbital artery is a feasible option for primary reconstruction of supraorbital-forehead defect.

[Modified Dihuang Decoction improves ovarian reserve in mice by regulating Bcl-2-related mitochondrial apoptosis pathway].

The present study investigated the effect of Modified Dihuang Decoction in improving ovarian reserve in mice through the Bcl-2-related mitochondrial apoptosis pathway. Forty-eight adult female BALB/c mice were randomly divided into the following six groups with eight mice in each group: a blank group, a model group, a femoston group(three cycles of treatment with 0.13 mg·kg~(-1) estradiol tablets for 2 days and 1.43 mg·kg~(-1) estradiol and dydrogesterone tablets for 3 days), and high(64.74 g·kg~(-1))-, medium(43.16 g·kg~(-1))-, and low-dose(21.58 g·kg~(-1)) Modified Dihuang Decoction groups. Mice in other groups except the blank group received a single intraperitoneal injection of 12 mg·kg~(-1) cyclophosphamide and 1.2 mg·kg~(-1) busulfan to induce a model of diminished ovarian reserve(DOR), while those in the blank group received an equal volume of normal saline. Mice were treated with corresponding drugs for 15 d from the 36 th day, once per day, and the mice in the blank group and the model group were treated with an equal volume of normal saline. The general condition and oestrous cycle were observed. The serum hormone levels were detected with the enzyme-linked immunosorbent assay(ELISA). The morphological changes of ovaries were observed by HE staining. Western blot was used to detect the protein expression of cysteinyl aspartate specific proteinase-9(caspase-9), cleaved caspase-3, Bcl-2 associated X protein(Bax), Bcl-2, superoxide dismutase-2(SOD-2), and glutathione peroxidase-1(GPx-1). The mRNA expression of Bax and Bcl-2 was detected by real-time fluorescence-based quantitative polymerase chain reaction(real-time PCR). The results showed that compared with the blank group, the model group showed body weight loss, disordered oestrous cycle, elevated serum levels of follicle-stimulating hormone(FSH) and luteinizing hormone(LH), reduced serum levels of estradiol(E_2), anti-mullerian hormone(AMH), and inhibin B(INHB), the declining number of ovarian follicles and granulosa layers, increased number of atretic follicles, up-regulated protein expression of caspase-9, cleaved caspase-3, and Bax and Bax mRNA expression in ovaries, and down-regulated protein expression of Bcl-2, SOD-2 and GPx-1, and Bcl-2 mRNA expression. Compared with the model group, the Modified Dihuang Decoction groups displayed restored body weight and oestrous cycle, decreased serum levels of FSH and LH, elevated serum levels of E_2, AMH, and INHB, increased number of ovarian follicles, thickened granulosa layers, and declining number of atretic follicles. Additionally, the protein expression of caspase-9, cleaved caspase-3, and Bax, and Bax mRNA expression was down-regulated, and the protein expression of Bcl-2, SOD-2, and GPx-1, and Bcl-2 mRNA expression was up-regulated. The results suggest that Modified Dihuang Decoction can regulate endocrine hormone, promote follicle growth and improve ovarian reserve by enhancing ovarian anti-oxidant capacity, inhibiting the Bcl-2-related mitochondrial apoptosis pathway, and further inhibiting cell apoptosis.

[Meta-analysis of Kuntai Capsules combined with GnRH-a in treatment of endometriosis].

To systemically evaluate the efficacy and safety of Kuntai Capsules combined with GnRH-a in the treatment of endome-triosis. The databases of CNKI, WanFang, VIP, PubMed, EMbase and Cochrane Library were searched from their establishment to May 2019 to collect the randomized controlled trials of Kuntai Capsules combined with GnRH-a in the treatment of endometriosis. The data were searched, screened and extracted by two researchers according to the inclusion and exclusion criteria, and the data were analyzed by using RevMan 5.3 software. A total of 58 articles were collected and 13 studies were included. The total sample size was 1 041 cases, including 523 cases in the experimental group and 518 cases in the control group. The results of Meta-analysis showed that Kuntai Capsules combined with GnRH-a can reduce the level of follicle stimulating hormone(FSH), luteinizing hormone(LH) and estradiol(E_2) in patients with endometriosis as compared with GnRH-a alone. With a low incidence of adverse events of peri-meno-pausal symptoms during treatment(RR=0.46, 95%CI[0.35, 0.60], P<0.000 01), it can reduce the VAS score of dysmenorrhea(MD=-1.85,95%CI[-1.92,-1.78],P<0.000 01). The recurrence rate in the combined treatment group was lower than that in the control group(RR=0.27, 95%CI[0.09,0.77], P=0.01). This study showed that Kuntai Capsules combined with GnRH-a can reduce the level of FSH, LH and E_2 in patients with endometriosis, reduce the VAS score of dysmenorrhea, with lower incidence of adverse events and recurrence rate, but it still needs large-scale, multicenter, randomized, double-blind and high-quality clinical trials for support and evidence.

QUATgo: Protein quaternary structural attributes predicted by two-stage machine learning approaches with heterogeneous feature encoding.

Many proteins exist in natures as oligomers with various quaternary structural attributes rather than as single chains. Predicting these attributes is an essential task in computational biology for the advancement of proteomics. However, the existing methods do not consider the integration of heterogeneous coding and the accuracy of subunit categories with limited data. To this end, we proposed a tool that can predict more than 12 subunit protein oligomers, QUATgo. Meanwhile, three kinds of sequence coding were used, including dipeptide composition, which was used for the first time to predict protein quaternary structural attributes, and protein half-life characteristics, and we modified the coding method of the functional domain composition proposed by predecessors to solve the problem of large feature vectors. QUATgo solves the problem of insufficient data for a single subunit using a two-stage architecture and uses 10-fold cross-validation to test the predictive accuracy of the classifier. QUATgo has 49.0% cross-validation accuracy and 31.1% independent test accuracy. In the case study, the accuracy of QUATgo can reach 61.5% for predicting the quaternary structure of influenza virus hemagglutinin proteins. Finally, QUATgo is freely accessible to the public as a web server via the site http://predictor.nchu.edu.tw/QUATgo.

Performance Characterization of Dye-Sensitized Photovoltaics under Indoor Lighting.

Indoor utilization of emerging photovoltaics is promising; however, efficiency characterization under room lighting is challenging. We report the first round-robin interlaboratory study of performance measurement for dye-sensitized photovoltaics (cells and mini-modules) and one silicon solar cell under a fluorescent dim light. Among 15 research groups, the relative deviation in power conversion efficiency (PCE) of the samples reaches an unprecedented 152%. On the basis of the comprehensive results, the gap between photometry and radiometry measurements and the response of devices to the dim illumination are identified as critical obstacles to the correct PCE. Therefore, we use an illuminometer as a prime standard with a spectroradiometer to quantify the intensity of indoor lighting and adopt the reverse-biased current-voltage (I-V) characteristics as an indicator to qualify the I-V sampling time for dye-sensitized photovoltaics. The recommendations can brighten the prospects of emerging photovoltaics for indoor applications.

Enhancement of mosquito trapping efficiency by using pulse width modulated light emitting diodes.

In this study, a light-driving bug zapper is presented for well controlling the diseases brought by insects, such as mosquitoes. In order to have the device efficient to trap the insect pests in off-grid areas, pulse width modulated light emitting diodes (PWM-LED) combined with a solar power module are proposed and implemented. With specific PWM electric signals to drive the LED, it is found that no matter what the ability of catching insects or the consumed power efficiency can be enhanced thus. It is demonstrated that 40% of the UV LED consumed power and 25.9% of the total load power consumption can be saved, and the trapped mosquitoes are about 250% increased when the PWM method is applied in the bug zapper experiments.

Comparative analysis of the folding dynamics and kinetics of an engineered knotted protein and its variants derived from HP0242 of Helicobacter pylori.

Understanding the mechanism by which a polypeptide chain thread itself spontaneously to attain a knotted conformation has been a major challenge in the field of protein folding. HP0242 is a homodimeric protein from Helicobacter pylori with intertwined helices to form a unique pseudo-knotted folding topology. A tandem HP0242 repeat has been constructed to become the first engineered trefoil-knotted protein. Its small size renders it a model system for computational analyses to examine its folding and knotting pathways. Here we report a multi-parametric study on the folding stability and kinetics of a library of HP0242 variants, including the trefoil-knotted tandem HP0242 repeat, using far-UV circular dichroism and fluorescence spectroscopy. Equilibrium chemical denaturation of HP0242 variants shows the presence of highly populated dimeric and structurally heterogeneous folding intermediates. Such equilibrium folding intermediates retain significant amount of helical structures except those at the N- and C-terminal regions in the native structure. Stopped-flow fluorescence measurements of HP0242 variants show that spontaneous refolding into knotted structures can be achieved within seconds, which is several orders of magnitude faster than previously observed for other knotted proteins. Nevertheless, the complex chevron plots indicate that HP0242 variants are prone to misfold into kinetic traps, leading to severely rolled-over refolding arms. The experimental observations are in general agreement with the previously reported molecular dynamics simulations. Based on our results, kinetic folding pathways are proposed to qualitatively describe the complex folding processes of HP0242 variants.

NMR assignments of a hypothetical pseudo-knotted protein HP0242 from Helicobacter pylori.

Many knotted proteins have been discovered recently, but the folding process of which remains elusive. HP0242 is a hypothetical protein from Helicobacter pylori, which is a model system for studying the folding pathway of a knotted protein. In this study, we report the (1)H, (13)C, and (15)N chemical shift assignments of HP0242. The results will enable us to further investigate HP0242 by NMR experiments.

Molecularly imprinted electrochemical sensor based on amine group modified graphene covalently linked electrode for 4-nonylphenol detection.

In this work, an imprinted electrochemical sensor based on electrochemical reduced graphene covalently modified carbon electrode was developed for the determination of 4-nonylphenol (NP). An amine-terminated functional graphene oxide was covalently modified onto the electrode surface with diazonium salt reactions to improve the stability and reproducibility of the imprinted sensor. The electrochemical properties of each modified electrodes were investigated with differential pulse voltammetry (DPV). The electrochemical characteristic of the imprinted sensor was also investigated using electrochemical impedance spectroscopy (EIS) in detail. The response currents of the imprinted electrode exhibited a linear relationship toward 4-nonylphenol concentration ranging from 1.0 × 10(-11) to 1.0 × 10(-8) gm L(-1) with the detection limit of 3.5 × 10(-12) gm L(-1) (S/N=3). The fabricated electrochemical imprinted sensor was successfully applied to the detection of 4-nonylphenol in rain and lake water samples.

Molecularly imprinted electrochemical sensor based on a reduced graphene modified carbon electrode for tetrabromobisphenol A detection.

A simple strategy for the indirect detection of 3,3',5,5'-tetrabromobisphenol A (TBBPA) was developed with a surface imprinted sensor based on an electrochemical reduced graphene modified carbon electrode. The preparation procedure of imprinted electrode and the response mechanism of the imprinted electrode toward TBBPA are discussed in detail. The electrochemical characteristics of the imprinted sensor were investigated using cyclic voltammetry and their morphologies were characterized using scanning electron microscopy. The indirect detection for TBBPA was successfully implemented by monitoring the peak current of Fe(CN)6(3-/4-)-TBBPA complex. The response currents of the imprinted sensor exhibited a linear relationship toward the TBBPA concentration range from 0.5 to 4.5 nM with a detection limit of 0.23 nM (S/N = 3). The fabricated electrochemical imprinted sensor was successfully applied to the detection of TBBPA in rain and lake water samples using the standard addition method. With the advantages of high sensitivity and simple operation, the determination methodology is a promising candidate for TBBPA detection in real water samples.

Circular permutation of the starch-binding domain: inversion of ligand selectivity with increased affinity.

Proteins containing starch-binding domains (SBDs) are used in a variety of scientific and technological applications. A circularly permutated SBD (CP90) with improved affinity and selectivity toward longer-chain carbohydrates was synthesized, suggesting that a new starch-binding protein may be developed for specific scientific and industrial applications.

A molten globule-to-ordered structure transition of Drosophila melanogaster crammer is required for its ability to inhibit cathepsin.

Drosophila melanogaster crammer is a novel cathepsin inhibitor that is involved in LTM (long-term memory) formation. The mechanism by which the inhibitory activity is regulated remains unclear. In the present paper we have shown that the oligomeric state of crammer is pH dependent. At neutral pH, crammer is predominantly dimeric in vitro as a result of disulfide bond formation, and is monomeric at acidic pH. Our inhibition assay shows that monomeric crammer, not disulfide-bonded dimer, is a strong competitive inhibitor of cathepsin L. Crammer is a monomeric molten globule in acidic solution, a condition that is similar to the environment in the lysosome where crammer is probably located. Upon binding to cathepsin L, however, crammer undergoes a molten globule-to-ordered structural transition. Using high-resolution NMR spectroscopy, we have shown that a cysteine-to-serine point mutation at position 72 (C72S) renders crammer monomeric at pH 6.0 and that the structure of the C72S variant highly resembles that of wild-type crammer in complex with cathepsin L at pH 4.0. We have determined the first solution structure of propeptide-like protease inhibitor in its active form and examined in detail using a variety of spectroscopic methods the folding properties of crammer in order to delineate its biomolecular recognition of cathepsin.

Effects of ligand binding on the dynamics of rice nonspecific lipid transfer protein 1: a model from molecular simulations.

Plant nonspecific lipid transfer proteins (nsLTPs) are small, basic proteins constituted mainly of alpha-helices and stabilized by four conserved disulfide bridges. They are characterized by the presence of a tunnel-like hydrophobic cavity, capable of transferring various lipid molecules between lipid bilayers in vitro. In this study, molecular dynamics (MD) simulations were performed at room temperature to investigate the effects of lipid binding on the dynamic properties of rice nsLTP1. Rice nsLTP1, either in the free form or complexed with one or two lipids was subjected to MD simulations. The C-terminal loop was very flexible both before and after lipid binding, as revealed by calculating the root-mean-square fluctuation. After lipid binding, the flexibility of some residues that were not in direct contact with lipid molecules increased significantly, indicating an increase of entropy in the region distal from the binding site. Essential dynamics analysis revealed clear differences in motion between unliganded and liganded rice nsLTP1s. In the free form of rice nsLTP1, loop1 exhibited the largest directional motion. This specific essential motion mode diminished after binding one or two lipid molecules. To verify the origin of the essential motion observed in the free form of rice nsLTP1, we performed multiple sequence alignments to probe the intrinsic motion encoded in the primary sequence. We found that the amino acid sequence of loop1 is highly conserved among plant nsLTP1s, thus revealing its functional importance during evolution. Furthermore, the sequence of loop1 is composed mainly of amino acids with short side chains. In this study, we show that MD simulations, together with essential dynamics analysis, can be used to determine structural and dynamic differences of rice nsLTP1 upon lipid binding.

Solution structure of family 21 carbohydrate-binding module from Rhizopus oryzae glucoamylase.

CBMs (carbohydrate-binding modules) function independently to assist carbohydrate-active enzymes. Family 21 CBMs contain approx. 100 amino acid residues, and some members have starchbinding functions or glycogen-binding activities. We report here the first structure of a family 21 CBM from the SBD (starch-binding domain) of Rhizopus oryzae glucoamylase (RoCBM21) determined by NMR spectroscopy. This CBM has a beta-sandwich fold with an immunoglobulin-like structure. Ligand-binding properties of RoCBM21 were analysed by chemical-shift perturbations and automated docking. Structural comparisons with previously reported SBDs revealed two types of topologies, namely type I and type II, with CBM20, CBM25, CBM26 and CBM41 showing type I topology, with CBM21 and CBM34 showing type II topology. According to the chemical-shift perturbations, RoCBM21 contains two ligand-binding sites. Residues in site II are similar to those found in the family 20 CBM from Aspergillus niger glucoamylase (AnCBM20). Site I, however, is embedded in a region with unique sequence motifs only found in some members of CBM21s. Additionally, docking of beta-cyclodextrin and malto-oligosaccharides highlights that side chains of Y83 and W47 (one-letter amino acid code) form the central part of the conserved binding platform in the SBD. The structure of RoCBM21 provides the first direct evidence of the structural features and the basis for protein-carbohydrate recognition from an SBD of CBM21.

Characterization and structural analyses of nonspecific lipid transfer protein 1 from mung bean.

Plant nonspecific lipid transfer proteins (nsLTPs) are thermal stable proteins that are capable of transferring lipid molecules between bilayers in vitro. This family of proteins, abundant in plants, is proposed to be involved in defense, pollination, and germination; the in vivo biological function remains, however, elusive. Here we report the purification and sequencing of an nsLTP1 from mung bean sprouts. We have also determined the solution structure of this nsLTP1, which represents the first 3D structure of the dicotyledonous nsLTP1 family. The global fold of mung bean nsLTP1 is similar to those of the monocotyledonous nsLTP1 structures and consists of four alpha-helices stabilized by four disulfide bonds. There are, however, some notable differences in the C-terminal tails and internal hydrophobic cavities. Circular dichroism and fluorescence spectroscopy were used to compare the thermodynamics and lipid transfer properties of mung bean nsLTP1 with those of rice nsLTP1. Docking of a lipid molecule into the solution structure of mung bean nsLTP1 reveals similar binding cavities and hydrophobic interactions as in rice nsLTP1, consistent with their comparable lipid transfer properties measured experimentally.

Mutagenesis study on the zebra fish SOX9 high-mobility group: comparison of sequence and non-sequence specific HMG domains.

A unique class of proteins, containing high-mobility group (HMG) domain(s), recognizes unusual DNA structures and/or bends specific to AT-rich linear double-stranded DNA. The DNA binding feature of these proteins is exhibited in the HMG domain(s). Although the sequence specific and non-sequence specific HMG domains exhibit very high degrees of sequence similarity, the reasons for the difference between their DNA recognition mechanisms are unclear. A series of zebra fish SOX9 HMG domain mutants was prepared in an effort to elucidate the importance of various residues on protein stability and DNA binding. This study is the first of a comprehensive mutagenesis study on a sequence specific HMG domain. Comparing how various residues influence sequence specific and non-sequence specific HMG domains helps us to rationalize their mode of action. Positively charged amino acids concentrated at the surface of sequence specific HMG domains recognize specific, linear AT-rich DNA segments. After the negative charges at the surface of the DNA are neutralized, the hydrophobic residues of the protein may intercalate DNA. Phenylalanine at position 12 plays a crucial role in the sequence specific HMG domain. The differences in pI values, the instability index, and DNA contact regions between sequence and non-sequence specific HMG domains are associated with their functional modes.