21.83% incident light can circumvent a 6.6 × 6.6 cm2 obstruction by introducing a layer of bubbles into the photovoltaic glass.

Obstruction is inevitable and will significantly impact the actual output performance of photovoltaic modules, even jeopardize their operational safety. We introduced a layer of bubbles into photovoltaic glass. These bubbles can alter the path of incident light, while the internal reflection at the glass/air interface enables the redirected light rays to have longer lateral propagation distance, circumventing the obstructions. The optimized photovoltaic glass with a bubble diameter of 1.8 mm and a surface density of 16 cm-2 enables the light intensity underneath a 6.6 × 6.6 cm2 obstruction to reach 21.83% of the incident light intensity. This enhancement permits a partial shading of the photovoltaic module, increasing its output power by ∼20.8% and decreasing the reverse bias voltage on the shaded cell by ∼1.4 V.

Characterizing the metabolic divide: distinctive metabolites differentiating CAD-T2DM from CAD patients.

OBJECTIVE: To delineate the metabolomic differences in plasma samples between patients with coronary artery disease (CAD) and those with concomitant CAD and type 2 diabetes mellitus (T2DM), and to pinpoint distinctive metabolites indicative of T2DM risk. METHOD: Plasma samples from CAD and CAD-T2DM patients across three centers underwent comprehensive metabolomic and lipidomic analyses. Multivariate logistic regression was employed to discern the relationship between the identified metabolites and T2DM risk. Characteristic metabolites' metabolic impacts were further probed through hepatocyte cellular experiments. Subsequent transcriptomic analyses elucidated the potential target sites explaining the metabolic actions of these metabolites. RESULTS: Metabolomic analysis revealed 192 and 95 significantly altered profiles in the discovery (FDR < 0.05) and validation (P < 0.05) cohorts, respectively, that were associated with T2DM risk in univariate logistic regression. Further multivariate regression analyses identified 22 characteristic metabolites consistently associated with T2DM risk in both cohorts. Notably, pipecolinic acid and L-pipecolic acid, lysine derivatives, exhibited negative association with CAD-T2DM and influenced cellular glucose metabolism in hepatocytes. Transcriptomic insights shed light on potential metabolic action sites of these metabolites. CONCLUSIONS: This research underscores the metabolic disparities between CAD and CAD-T2DM patients, spotlighting the protective attributes of pipecolinic acid and L-pipecolic acid. The comprehensive metabolomic and transcriptomic findings provide novel insights into the mechanism research, prophylaxis and treatment of comorbidity of CAD and T2DM.

Improving carrier separation at the TiO2/CsPbIBr2 interface by gradient Sn-doping.

Subhani et al. found that Sm-doping in CsPbIBr2 decreased its bandgap from 2.05 eV to 1.8 eV; thus, the efficiency of CsPbIBr2 solar cells was improved by ∼30%. However, Sm is a vital strategic resource with high costs. Metal Sn is much more abundant and cheaper than Sm; meanwhile, it has been proven that Sn can adjust the bandgap of CsPbIBr2 in a broader range, 2.05 eV to 1.64 eV. Therefore, Sn-doping in CsPbIBr2 may improve the efficiency of CsPbIBr2 solar cells, even to a greater extent. In this work, we established the TiO2/CsPbIBr2 interface model by gradient Sn-doping in CsPbIBr2 and investigated the impacts of such gradient doping on the carrier separation behaviors at the TiO2/CsPbIBr2 interface from the aspects of the cross-interface electric field, bandgap, and band matching, based on first-principles calculations. It is found that gradient Sn-doping can transfer more electrons from TiO2 to perovskites, thus creating an enhanced cross-interface electric field conducive to the separation of carriers at the TiO2/CsPbIBr2 interface. Affected by the existence of the interface, the bandgap of each perovskite layer gradually increases as it moves away from the interface; in addition, due to the gradient Sn-doping, the steps between the bandgaps of adjacent perovskite layers become smaller and more uniform, which is favorable for the separation of electrons. In summary, gradient Sn-doping can improve the carrier separation at the TiO2/CsPbIBr2 interface.

Blistering1 Modulates Penicillium expansum Virulence Via Vesicle-mediated Protein Secretion.

The blue mold fungus, Penicillium expansum, is a postharvest apple pathogen that contributes to food waste by rotting fruit and by producing harmful mycotoxins (e.g. patulin). To identify genes controlling pathogen virulence, a random T-DNA insertional library was created from wild-type P. expansum strain R19. One transformant, T625, had reduced virulence in apples, blistered mycelial hyphae, and a T-DNA insertion that abolished transcription of the single copy locus in which it was inserted. The gene, Blistering1, encodes a protein with a DnaJ domain, but otherwise has little homology outside the Aspergillaceae, a family of fungi known for producing antibiotics, mycotoxins, and cheese. Because protein secretion is critical for these processes and for host infection, mass spectrometry was used to monitor proteins secreted into liquid media during fungal growth. T625 failed to secrete a set of enzymes that degrade plant cell walls, along with ones that synthesize the three final biosynthetic steps of patulin. Consequently, the culture broth of T625 had significantly reduced capacity to degrade apple tissue and contained 30 times less patulin. Quantitative mass spectrometry of 3,282 mycelial proteins revealed that T625 had altered cellular networks controlling protein processing in the endoplasmic reticulum, protein export, vesicle-mediated transport, and endocytosis. T625 also had reduced proteins controlling mRNA surveillance and RNA processing. Transmission electron microscopy of hyphal cross sections confirmed that T625 formed abnormally enlarged endosomes or vacuoles. These data reveal that Blistering1 affects internal and external protein processing involving vesicle-mediated transport in a family of fungi with medical, commercial, and agricultural importance.

An Efficient and Accurate Iris Recognition Algorithm Based on a Novel Condensed 2-ch Deep Convolutional Neural Network.

Recently, deep learning approaches, especially convolutional neural networks (CNNs), have attracted extensive attention in iris recognition. Though CNN-based approaches realize automatic feature extraction and achieve outstanding performance, they usually require more training samples and higher computational complexity than the classic methods. This work focuses on training a novel condensed 2-channel (2-ch) CNN with few training samples for efficient and accurate iris identification and verification. A multi-branch CNN with three well-designed online augmentation schemes and radial attention layers is first proposed as a high-performance basic iris classifier. Then, both branch pruning and channel pruning are achieved by analyzing the weight distribution of the model. Finally, fast finetuning is optionally applied, which can significantly improve the performance of the pruned CNN while alleviating the computational burden. In addition, we further investigate the encoding ability of 2-ch CNN and propose an efficient iris recognition scheme suitable for large database application scenarios. Moreover, the gradient-based analysis results indicate that the proposed algorithm is robust to various image contaminations. We comprehensively evaluated our algorithm on three publicly available iris databases for which the results proved satisfactory for real-time iris recognition.

Localized surface plasmon mode-enhanced spectrum-tunable radiation in electrically driven plasmonic antennas.

A spectrum-tunable source with ultra-small volume is highly desired by on-chip information processing technologies. As a promising candidate, light emission from electrically driven tunnel junctions has gained much interest. In this Letter, using a gap bowtie antenna-based metal-insulator-metal junction as the source, multiple peaks are found in the electroluminescence spectrum of the antenna system. We attribute the peaks observed in the experimental emission spectrum to resonant plasmon modes that are supported by the antennas. This explanation is confirmed numerically by finite difference time domain calculations and analytically by using a theory imitated from scanning tunneling microscopy. Our results show that the localized surface plasmon modes can be finely tuned by varying the gap distances and the geometries of the antennas, which eventually contribute to a spectrum-tunable light source. This Letter may provide a path for spectrum-tunable electrically driven light sources on photonic devices.

Characterization of the daucosterol-lecithin complex and its impact on lipid metabolism in hyperlipidemic mice.

This investigation delves into the daucosterol-lecithin complex (DS-LC) and its effects on lipid homeostasis in hyperlipidemic mice. DS-LC was assessed for complexation efficiency, physicochemical properties (UV, XRD, FTIR, SEM, DSC), and its impact on organ health and serum lipid levels. The results revealed that daucosterol formed an effective complex with lecithin at a 2 : 1 ratio, producing a translucent beige DS-LC with distinctive aggregation. UV-vis spectra confirmed that daucosterol's chromophore structure remained intact in DS-LC, indicating no new compound formation. FTIR analysis identified hydrogen bonding and increased molecular association without changing lecithin peaks, highlighting specific intermolecular interactions. SEM and XRD showed that complexation transformed daucosterol into an irregular form within the lecithin matrix, forming a new phase and demonstrating a strong lecithin-daucosterol interaction. Thermal analysis suggested homogeneous daucosterol distribution due to intermolecular interactions. DS-LC treatment effectively alleviated hyperlipidemia, enhancing liver function and reducing lipid accumulation in epididymal fat. It also significantly decreased total cholesterol, triglycerides, LDL-C, and arteriosclerosis index in hyperlipidemic mice, indicating DS-LC's potential as a therapeutic agent for lipid metabolism and related metabolic disorders.

Causal associations of genetically predicted gut microbiota and blood metabolites with inflammatory states and risk of infections: a Mendelian randomization analysis.

Background: Inflammation serves as a key pathologic mediator in the progression of infections and various diseases, involving significant alterations in the gut microbiome and metabolism. This study aims to probe into the potential causal relationships between gut microbial taxa and human blood metabolites with various serum inflammatory markers (CRP, SAA1, IL-6, TNF-α, WBC, and GlycA) and the risks of seven common infections (gastrointestinal infections, dysentery, pneumonia, bacterial pneumonia, bronchopneumonia and lung abscess, pneumococcal pneumonia, and urinary tract infections). Methods: Two-sample Mendelian randomization (MR) analysis was performed using inverse variance weighted (IVW), maximum likelihood, MR-Egger, weighted median, and MR-PRESSO. Results: After adding other MR models and sensitivity analyses, genus Roseburia was simultaneously associated adversely with CRP (Beta IVW = -0.040) and SAA1 (Beta IVW = -0.280), and family Bifidobacteriaceae was negatively associated with both CRP (Beta IVW = -0.034) and pneumonia risk (Beta IVW = -0.391). After correction by FDR, only glutaroyl carnitine remained significantly associated with elevated CRP levels (Beta IVW = 0.112). Additionally, threonine (Beta IVW = 0.200) and 1-heptadecanoylglycerophosphocholine (Beta IVW = -0.246) were found to be significantly associated with WBC levels. Three metabolites showed similar causal effects on different inflammatory markers or infectious phenotypes, stearidonate (18:4n3) was negatively related to SAA1 and urinary tract infections, and 5-oxoproline contributed to elevated IL-6 and SAA1 levels. In addition, 7-methylguanine showed a positive correlation with dysentery and bacterial pneumonia. Conclusion: This study provides novel evidence confirming the causal effects of the gut microbiome and the plasma metabolite profile on inflammation and the risk of infection. These potential molecular alterations may aid in the development of new targets for the intervention and management of disorders associated with inflammation and infections.

Association between oxidative balance score, systemic inflammatory response index, and cardiovascular disease risk: a cross-sectional analysis based on NHANES 2007-2018 data.

Background: There is limited research on the relationship between Systemic Oxidative Stress (SOS) status and inflammatory indices. Adding onto existing literature, this study aimed to examine the association between dietary Oxidative Balance Score (OBS) and lifestyle OBS (which make up the overall OBS), and Cardiovascular Disease (CVD) prevalence at different Systemic Immune Inflammation Index (SII) and Systemic Inflammatory Response Index (SIRI) levels. Methods: This study involved 9,451 subjects selected from the National Health and Nutrition Examination Survey (NHANES) 2007-2018. The OBS comprised 20 dietary and lifestyle factors. Statistical methods included Weighted Linear Regression Analysis (WLRA), Logistic Regression Analysis (LRA), Sensitivity Analysis (SA), and Restricted Cubic Spline (RCS) analysis. Results: The multivariate WLRA revealed that OBS was significantly negatively correlated with both SII (ß = -5.36, p < 0.001) and SIRI (ß = -0.013, p < 0.001) levels. In SA, removing any single OBS component had no significant effect on the WLRA results of SII and SIRI. Further subgroup analyses revealed that OBS was more impactful in lowering SII in women than in men. Additionally, OBS was more significantly negatively correlated with SII and SIRI in the low-age group than in the high-age group. Moreover, RCS analysis confirmed this linear relationship. Compared to dietary OBS, lifestyle OBS exerted a more significant effect on Coronary Artery Disease (CAD) (OR: 0.794, p = 0.002), hypertension (OR: 0.738, p < 0.001), Congestive Heart Failure (CHF) (OR: 0.736, p = 0.005), Myocardial Infarction (MI) (OR: 0.785, p = 0.002), and stroke (OR: 0.807, p = 0.029) prevalence. Furthermore, SIRI exhibited a significant interaction in the relationship between overall OBS, dietary OBS, and CHF (P for interaction < 0.001). On the other hand, SII had a significant interaction in the relationship between overall OBS, dietary OBS, and MI (P for interaction < 0.05). Conclusion: OBS, including lifestyle and dietary OBS, were significantly negatively associated with SII and SIRI. Higher lifestyle OBS was associated with reduced risks of CAD, hypertension, CHF, MI, and stroke.

Multi-functional adhesive hydrogel as bio-interface for wireless transient pacemaker.

Traditional temporary cardiac pacemakers (TCPs), which employ transcutaneous leads and external wired power systems are battery-dependent and generally non-absorbable with rigidity, thereby necessitating surgical retrieval after therapy and resulting in potentially severe complications. Wireless and bioresorbable transient pacemakers have, hence, emerged recently, though hitting a bottleneck of unfavorable tissue-device bonding interface subject to mismatched mechanical modulus, low adhesive strength, inferior electrical performances, and infection risks. Here, to address such crux, we develop a multifunctional interface hydrogel (MIH) with superior electrical performance to facilitate efficient electrical exchange, comparable mechanical strength to natural heart tissue, robust adhesion property to enable stable device-tissue fixation (tensile strength: ∼30 kPa, shear strength of ∼30 kPa, and peel-off strength: ∼85 kPa), and good bactericidal effect to suppress bacterial growth. Through delicate integration of this versatile MIH with a leadless, battery-free, wireless, and transient pacemaker, the entire system exhibits stable and conformal adhesion to the beating heart while enabling precise and constant electrical stimulation to modulate the cardiac rhythm. It is envisioned that this versatile MIH and the proposed integration framework will have immense potential in overcoming key limitations of traditional TCPs, and may inspire the design of novel bioelectronic-tissue interfaces for next-generation implantable medical devices.

HiDeNN-FEM: A seamless machine learning approach to nonlinear finite element analysis.

The hierarchical deep-learning neural network (HiDeNN) (Zhang et al, Computational Mechanics, 67:207-230) provides a systematic approach to constructing numerical approximations that can be incorporated into a wide variety of Partial differential equations (PDE) and/or Ordinary differential equations (ODE) solvers. This paper presents a framework of the nonlinear finite element based on HiDeNN approximation (nonlinear HiDeNN-FEM). This is enabled by three basic building blocks employing structured deep neural networks: 1) A partial derivative operator block that performs the differentiation of the shape functions with respect to the element coordinates, 2) An r-adaptivity block that improves the local and global convergence properties and 3) A materials derivative block that evaluates the material derivatives of the shape function. While these building blocks can be applied to any element, specific implementations are presented in 1D and 2D to illustrate the application of the deep learning neural network. Two-step optimization schemes are further developed to allow for the capabilities of r-adaptivity and easy integration with any existing FE solver. Numerical examples of 2D and 3D demonstrate that the proposed nonlinear HiDeNN-FEM with r-adaptivity provides much higher accuracy than regular FEM. It also significantly reduces element distortion and suppresses the hourglass mode.

Exploring the causal effects of the gut microbiome on serum lipid levels: A two-sample Mendelian randomization analysis.

Background: The gut microbiome was reported to be associated with dyslipidemia in previous observational studies. However, whether the composition of the gut microbiome has a causal effect on serum lipid levels remains unclear. Objective: A two-sample Mendelian randomization (MR) analysis was conducted to investigate the potential causal relationships between gut microbial taxa and serum lipid levels, including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and log-transformed triglyceride (TG) levels. Materials and methods: Summary statistics of genome-wide association studies (GWASs) for the gut microbiome and four blood lipid traits were obtained from public datasets. Five recognized MR methods were applied to assess the causal estimates, among which, the inverse-variance weighted (IVW) regression was used as the primary MR method. A series of sensitivity analyses were performed to test the robustness of the causal estimates. Results: The combined results from the five MR methods and sensitivity analysis showed 59 suggestive causal associations and four significant causal associations. In particular, genus Terrisporobacter was associated with higher LDL-C (P IVW = 3.01 × 10-6) and TC levels (P IVW = 2.11 × 10-4), phylum Actinobacteria was correlated with higher LDL-C level (P IVW = 4.10 × 10-4), and genus Oscillospira was associated with lower TG level (P IVW = 2.19 × 10-6). Conclusion: This research may provide novel insights into the causal relationships of the gut microbiome on serum lipid levels and new therapeutic or prevention strategies for dyslipidemia.

Selectively Fluorinated Citronellol Analogues Support a Hydrogen Bonding Donor Interaction with the Human OR1A1 Olfactory Receptor.

C-2 fluorinated and methylated stereoisomers of the fragrance citronellol 1 and its oxalate esters were prepared from (R)-pulegone 11 and explored as agonists of the human olfactory receptor OR1A1 and assayed also against site-specific mutants. There were clear isomer preferences and C-2 difluorination as in 18 led to the most active compound suggesting an important hydrogen bond donor role for citronellol 1. C-2 methylation and the corresponding oxalate ester analogues were less active.

A biomimetic olfactory recognition system for the discrimination of Chinese liquor aromas.

Aroma is an important attribute influencing the perceived quality of Chinese liquors, with each liquor characterized by a unique collection of volatile chemicals. Here, a biomimetic olfactory recognition system combining an optimal panel of 10 mouse odorant receptors with back propagation neural network model was designed to discriminate the aromas of Chinese liquors. Our system shows an excellent predictive capacity with an average accuracy of 96.5% to discriminate liquors of different aroma types, as well as those of different brands and ageing years within the same aroma type. A total of 124 interactions between liquor aroma compounds and odorant receptors were further elucidated to understand odorant coding at the molecular level, including 14 newly deorphaned odorant receptors. Our work represents a proof of concept for combining receptors and machine learning in the discrimination of complex odorant stimuli.

Neuromodulation Effect of Very Low Intensity Transcranial Ultrasound Stimulation on Multiple Nuclei in Rat Brain.

OBJECTIVE: Low-intensity transcranial ultrasound stimulation (TUS) is a non-invasive neuromodulation technique with high spatial resolution and feasible penetration depth. To date, the mechanisms of TUS modulated neural oscillations are not fully understood. This study designed a very low acoustic intensity (AI) TUS system that produces considerably reduced AI Ultrasound pulses (I SPTA < 0.5 W/cm2) when compared to previous methods used to measure regional neural oscillation patterns under different TUS parameters. METHODS: We recorded the local field potential (LFP) of five brain nuclei under TUS with three groups of simulating parameters. Spectrum estimation, time-frequency analysis (TFA), and relative power analysis methods have been applied to investigate neural oscillation patterns under different stimulation parameters. RESULTS: Under PRF, 500 Hz and 1 kHz TUS, high-amplitude LFP activity with the auto-rhythmic pattern appeared in selected nuclei when I SPTA exceeded 12 mW/cm2. With TFA, high-frequency energy (slow gamma and high gamma) was significantly increased during the auto-rhythmic patterns. We observed an initial plateau in nuclei response when I SPTA reached 16.4 mW/cm2 for RPF 500 Hz and 20.8 mW/cm2 for RPF 1 kHz. The number of responding nuclei started decreasing while I SPTA continued increasing. Under 1.5 kHz TUS, no auto-rhythmic patterns have been observed, but slow frequency power was increased during TUS. TUS inhibited most of the frequency band and generated obvious slow waves (theta and delta band) when stimulated at RPF = 1.5 kHz, I SPTA = 8.8 mW/cm2. CONCLUSION: These results demonstrate that very low intensity Transcranial Ultrasound Stimulation (VLTUS) exerts significant neuromodulator effects under specific parameters in rat models and may be a valid tool to study neuronal physiology.

Glycolytic preconditioning in astrocytes mitigates trauma-induced neurodegeneration.

Concussion is associated with a myriad of deleterious immediate and long-term consequences. Yet the molecular mechanisms and genetic targets promoting the selective vulnerability of different neural subtypes to dysfunction and degeneration remain unclear. Translating experimental models of blunt force trauma in C. elegans to concussion in mice, we identify a conserved neuroprotective mechanism in which reduction of mitochondrial electron flux through complex IV suppresses trauma-induced degeneration of the highly vulnerable dopaminergic neurons. Reducing cytochrome C oxidase function elevates mitochondrial-derived reactive oxygen species, which signal through the cytosolic hypoxia inducing transcription factor, Hif1a, to promote hyperphosphorylation and inactivation of the pyruvate dehydrogenase, PDHE1α. This critical enzyme initiates the Warburg shunt, which drives energetic reallocation from mitochondrial respiration to astrocyte-mediated glycolysis in a neuroprotective manner. These studies demonstrate a conserved process in which glycolytic preconditioning suppresses Parkinson-like hypersensitivity of dopaminergic neurons to trauma-induced degeneration via redox signaling and the Warburg effect.

Concussion is a type of traumatic brain injury that results from a sudden blow or jolt to the head. Symptoms can include a passing headache, dizziness, confusion or sensitivity to light, but experiencing multiple concussions can have drastic repercussions in later life. Studies of professional athletes have shown that those who experience one or more concussions are prone to developing Alzheimer's and Parkinson's disease, two well-known neurodegenerative diseases. Both conditions involve the progressive loss or breakdown of nerve cells, called neurons. But exactly how this so-called neurodegeneration of brain cells stems from the original, physical injury remains unclear. Head trauma may cause damage to the structural support of a cell or disrupt the flow of electrical impulses through neurons. Energy use and production in damaged cells could shift into overdrive to repair the damage. The chemical properties of different types of brain cells could also make some more vulnerable to trauma than others. Besides neurons, star-shaped support cells in the brain called astrocytes, which may have some protective ability, could also be affected. To investigate which cells may be more susceptible to traumatic injuries, Solano Fonseca et al. modelled the impacts of concussion-like head trauma in roundworms (C. elegans) and mice. In both animals, one type of neuron was extremely vulnerable to cell death after trauma. Neurons that release dopamine, a chemical involved in cell-to-cell communication and the brain's reward system, showed signs of cell damage and deteriorated after injury. Dopaminergic cells, as these cells are called, are involved in motor coordination, and the loss of dopaminergic cells has been linked to both Alzheimer's and Parkinson's disease. Astrocytes, however, had a role in reducing the death of dopaminergic neurons after trauma. In experiments, astrocytes appeared to restore the balance of energy production to meet the increased energy demands of impacted neurons. Single-cell analyses showed that genes involved in metabolism were switched on in astrocytes to produce energy via an alternative pathway. This energetic shift facilitated via astrocytes may help mitigate against some damage to dopamine-producing neurons after trauma, reducing cell death. This work furthers our understanding of cellular changes in the concussed brain. More research will be required to better characterise how this immediate trauma to cells, and the subsequent loss of dopaminergic neurons, impacts brain health long-term. Efforts to design effective therapies to slow or reverse these changes could then follow.

Expression and significance of IGF-1 and IGF-1R in thyroid nodules.

There are limitations in the diagnosis of thyroid nodules, especially follicular lesions, and their pathogenesis remains unclear. Insulin-like growth factor-1 (IGF-1) has been implicated in tumor cell apoptosis, transformation, invasion, and metastasis; however, its role in thyroid nodules is undetermined. The aim of this study is to investigate the relationship between expression of IGF-1 and thyroid nodule, and evaluate the role of IGF-1 in differential diagnosis and pathogenetic function of benign and malignant thyroid nodules. Sixty-two paraffin-embedded thyroid tissues from patients with thyroid nodules were selected, including 18 follicular adenomas (FA), 17 nodular goiters, 13 papillary thyroid carcinomas (PTC), 2 follicular thyroid carcinomas, and 12 normal controls. IGF-1 and IGF-1R protein and mRNA expression was detected by immunohistochemistry (IHC) and real-time quantitative PCR (qRT-PCR), respectively. Grouping comparisons were employed among the above groups based on the clinical and pathological subtypes. IGF-1 and IGF-1R expression was significantly higher in FA, nodular goiters, and PTC than that in the controls (all P < 0.01). Similarly, IGF-1 mRNA expression was also significantly higher in FA (P < 0.05), nodular goiters (P < 0.01), and PTC (P < 0.01) compared with the controls. IGF-1R mRNA expression was also significantly higher in FA, nodular goiters, and PTC (all P < 0.01) compared with the controls. Compared with FA and nodular goiters, PTC showed significantly higher IGF-1 and IGF-1R protein (P < 0.01, P < 0.05, respectively) and mRNA expression (P < 0.01, P < 0.05, respectively). IGF-1 probably plays an important role in the genesis and development of certain solid cold thyroid nodules, including PTC, nodular goiters, and FA. Detection of IGF-1 and IGF-1R expression in thyroid tissues by IHC or qRT-PCR is hard to distinguish malignant from benign lesions.

Association of insulin-like growth factor-1 with thyroid nodules.

The aim of the present study was to investigate the relationship between insulin-like growth factor-1 (IGF-1) and thyroid nodules. A total of 56 patients with thyroid nodules confirmed by physical examination and ultrasound screening were randomly selected. The patients were divided into three groups by radionuclide scan: the hot nodule group (group 1, n=18); the cold and solid nodule group (group 2, n=18); and the cold and cystic nodule group (group 3, n=20). Cystic fluid samples from patients with cystic cold thyroid nodules were defined as group 4. A control group of 18 healthy adults matched for age, gender and body mass index (group 0) was also included. For all participants, levels of the thyroid hormones, TT3, TT4, TSH and IGF-1, were determined by radioimmunoassay. The measurement data were expressed as the mean ± standard deviation (SD). The analysis of variance was performed by the t-test and the correlation analysis was performed by linear regression. The serum levels of IGF-1 in the solid cold nodule group were significantly higher than those in the hot nodule group (P<0.05). Serum levels of IGF-1 in the cystic cold nodule group were significantly lower than those in the control group (P<0.05). The serum IGF-1 levels in the cystic fluid were significantly lower than those in the cystic cold nodule (P<0.05) and the control groups (P<0.05). Additionally, the mean serum IGF-1 level in patients with thyroid adenoma was significantly higher than that in the control group (P<0.05). The serum IGF-1 level may not be involved in the pathogenesis of hot thyroid nodules and cold and cystic thyroid nodules; however, it may play a significant role in the pathogenesis of certain solid cold thyroid nodules.