In Vivo Blood Glucose Quantification Using Raman Spectroscopy

We here propose a novel Raman spectroscopy method that permits the noninvasive measurement of blood glucose concentration. To reduce the effects of the strong background signals produced by surrounding tissue and to obtain the fingerprint Raman lines formed by blood analytes, a laser was focused on the blood in vessels in the skin. The Raman spectra were collected transcutaneously. Characteristic peaks of glucose (1125 cm(-1)) and hemoglobin (1549 cm(-1)) were observed. Hemoglobin concentration served as an internal standard, and the ratio of the peaks that appeared at 1125 cm(-1) and 1549 cm(-1) peaks was used to calculate the concentration of blood glucose. We studied three mouse subjects whose blood glucose levels became elevated over a period of 2 hours using a glucose test assay. During the test, 25 Raman spectra were collected transcutaneously and glucose reference values were provided by a blood glucose meter. Results clearly showed the relationship between Raman intensity and concentration. The release curves were approximately linear with a correlation coefficient of 0.91. This noninvasive methodology may be useful for the study of blood glucose in vivo

Iron induces two distinct Ca²⁺ signalling cascades in astrocytes.

From Europe PMC via Jisc Publications RouterHistory: ppub 2021-05-01, epub 2021-05-05Publication status: PublishedFunder: National Natural Science Foundation of China (National Science Foundation of China); Grant(s): 81871852Iron is the fundamental element for numerous physiological functions. Plasmalemmal divalent metal ion transporter 1 (DMT1) is responsible for cellular uptake of ferrous (Fe2+), whereas transferrin receptors (TFR) carry transferrin (TF)-bound ferric (Fe3+). In this study we performed detailed analysis of the action of Fe ions on cytoplasmic free calcium ion concentration ([Ca2+]i) in astrocytes. Administration of Fe2+ or Fe3+ in μM concentrations evoked [Ca2+]i in astrocytes in vitro and in vivo. Iron ions trigger increase in [Ca2+]i through two distinct molecular cascades. Uptake of Fe2+ by DMT1 inhibits astroglial Na+-K+-ATPase, which leads to elevation in cytoplasmic Na+ concentration, thus reversing Na+/Ca2+ exchanger and thereby generating Ca2+ influx. Uptake of Fe3+ by TF-TFR stimulates phospholipase C to produce inositol 1,4,5-trisphosphate (InsP3), thus triggering InsP3 receptor-mediated Ca2+ release from endoplasmic reticulum. In summary, these findings reveal the mechanisms of iron-induced astrocytic signalling operational in conditions of iron overload

VgrG and PAAR Proteins Define Distinct Versions of a Functional Type VI Secretion System

The Type VI secretion system (T6SS) is widespread among bacterial pathogens and acts as an effective weapon against competitor bacteria and eukaryotic hosts by delivering toxic effector proteins directly into target cells. The T6SS utilises a bacteriophage-like contractile machinery to expel a puncturing device based on a tube of Hcp topped with a VgrG spike, which can be extended by a final tip from a PAAR domain-containing protein. Effector proteins are believed to be delivered by specifically associating with particular Hcp, VgrG or PAAR proteins, either covalently ('specialised') or non-covalently ('cargo' effectors). Here we used the T6SS of the opportunistic pathogen Serratia marcescens, together with integratecd genetic, proteomic and biochemical approaches, to elucidate the role of specific VgrG and PAAR homologues in T6SS function and effector specificity, revealing new aspects and unexpected subtleties in effector delivery by the T6SS. We identified effectors, both cargo and specialised, absolutely dependent on a particular VgrG for delivery to target cells, and discovered that other cargo effectors can show a preference for a particular VgrG. The presence of at least one PAAR protein was found to be essential for T6SS function, consistent with designation as a 'core' T6SS component. We showed that specific VgrG-PAAR combinations are required to assemble a functional T6SS and that the three distinct VgrG-PAAR assemblies in S. marcescens exhibit distinct effector specificity and efficiency. Unexpectedly, we discovered that two different PAAR-containing Rhs proteins can functionally pair with the same VgrG protein. Showing that accessory EagR proteins are involved in these interactions, native VgrG-Rhs-EagR complexes were isolated and specific interactions between EagR and cognate Rhs proteins identified. This study defines an essential yet flexible role for PAAR proteins in the T6SS and highlights the existence of distinct versions of the machinery with differential effector specificity and efficiency of target cell delivery

The Influence of Different Caregivers on Infant Growth and Development in China

ObjectiveAn increasing number of parents in China ask grandparents or babysitters to care for their children. Modern parents are often the only child in their family because of China’s One-Child Policy and thus may lack interaction with siblings. Accordingly, the present study aimed to explore whether different caregivers affect the physical and development of infants in China.MethodsIn total, 2,514 infants were enrolled in our study. We assessed their weight-for-age, supine length-for-age, weight-for-length, occipital-frontal circumference, and Denver Developmental Screening Test (DDST) results and recorded their general parental information and their primary caregivers.ResultsThe weights and lengths of 12-month-old infants under the care of babysitters were significantly lower than those of infants under the care of parents or grandparents (P < 0.05). Additionally, 12-month-old infants under the care of babysitters had the lowest DDST pass rate (75%) among the three groups (χ2 = 11.819, P = 0.012), especially for the fine motor-adaptive and language domains. Compared to 12-month-old infants under the care of parents and babysitters, infants under the care of grandparents were more likely to be overweight or obese (P < 0.001).ConclusionThe study showed that caregivers had a dominant role in the physical and cognitive development of the infants. Specifically, compared with infants raised by grandparents and parents, 12-month-old infants under the care of babysitters had partially suppressed lengths and weights and lagged cognitively. The 12-month-old infants under the care of grandparents were more overweight than those cared for by parents and babysitters

Wolf's isotopic response: a case of localized bullous pemphigoid on the herpes zoster scar

A case of Wolf's isotopic response is reported. A 68-year-old-female presented with vesicles and bullae on the scars of the left chest and the back for 2 months. Dermatological examination revealed five vesicles and bullae of various sizes on the edge of a 10 cm×5 cm scar, with a deep central ulcer sized 5 cm×5 cm, under the left armpit. Ulcer was with little discharge and dark crusts. The vesicles were with clear fluid and negative for Nikolsky's sign. Two bullae were seen on a 3 cm×2 cm hypertrophic scar at T2 to T4 of the left anterior chest. One hypertrophic scar with a bulla sized 1.5 cm and another one with 1 cm erosion and pustular secretion were on the left back. Patient had no mucosal involvement. Histology of skin lesion showed subepidermal blister and perivascular infiltrates of a few lymphohistiocytes, neutrophils and plasma cells in the superficial dermis. Direct immunofluorescence showed linear deposition of C3 in the basement membrane zone. The diagnosis was isotopic response: bullous pemphigoid secondary to herpes zoster. After the treatment with oral prednisone acetate, the blisters resolved in 2 weeks. No recurrence was observed during 15-months follow-up. The follow-up is still ongoing

Reduction of selenite and tellurite by a highly metal-tolerant marine bacterium

Selenium (Se) and tellurium (Te) contaminations in soils and water bodies have been widely reported in recent years. Se(IV) and Te(IV) were regarded as their most dangerous forms. Microbial treatments of Se(IV)- and Te(IV)-containing wastes are promising approaches because of their environmentally friendly and sustainable advantages. However, the salt-tolerant microbial resources that can be used for selenium/tellurium pollution control are still limited since industrial wastewaters usually contain a large number of salts. In this study, a marine Shewanella sp. FDA-1 (FDA-1) was reported for efficient Se(IV) and Te(IV) reduction under saline conditions. Process and product analyses were performed to investigate the bioreduction processes of Se(IV) and Te(IV). The results showed that FDA-1 can effectively reduce Se(IV) and Te(IV) to Se-0 and Te-0 Se(IV)/Te(IV) to Se-0/Te-0 in 72 h, which were further confirmed by XRD and XPS analyses. In addition, enzymatic and RT-qPCR assays showed that flavin-related proteins, reductases, dehydrogenases, etc., could be involved in the bioreduction of Se(IV)/Te(IV). Overall, our results demonstrate the ability of FDA-1 to reduce high concentrations of Se(IV)/or Te(IV) to Se-0/or Te-0 under saline conditions and thus provide efficient microbial candidate for controlling Se and Te pollution

Intrinsic Phase Stability and Inherent Bandgap of Formamidinium Lead Triiodide Perovskite Single Crystals

Understanding the intrinsic phase stability and inherent band gap of formamidinium lead triiodide (FAPbI(3)) perovskites is crucial to further improve the performance of perovskite solar cells (PSCs). Herein, we explored the alpha- to delta-phase transition and band gap of FAPbI(3) single crystals grown by an inverse temperature solubility method. We found that the residual gamma-butyrolactone solvents in the inner empty space of the FAPbI(3) single crystal accelerate the phase transition at kinetics. By adopting 2-methoxyethanol as the solvent, over 2000 h of stable alpha-FAPbI(3) crystals could be acquired. This proves that although FAPbI(3) is regarded as unstable at thermodynamics, it could own excellent kinetic stability without any doping or additives because of the slow solid to solid phase transition instead of the fast phase transition assisted by the solvents. Furthermore, we revealed that the bulk FAPbI(3) single crystal with a size above 100 mu m can have an inherent band gap of 1.41 eV. Thus, our work provides key scientific guidance for high-performance FAPbI(3)-based PSCs

Chemical composition of essential oil in Mosla chinensis Maxim cv. Jiangxiangru and its inhibitory effect on Staphylococcus aureus biofilm formation

The essential oil of Mosla chinensis Maxim cv. Jiangxiangru is known for its antibacterial ability. This study aimed to investigate the chemical composition of Jiangxiangru essential oil and its inhibitory effect on Staphylococcus aureus biofilm formation. Gas chromatography/mass spectrometry (GC–MS) was used to determine the chemical composition of Jiangxiangru essential oil. Subsequently, the eight major chemical components were quantitatively analyzed using GC– MS, and their minimum inhibitory concentration (MIC) values against S. aureus were tested. Biofilm formation was detected by crystal violet semi-quantitative method and silver staining. Of the 59 peaks detected, 29 were identified by GC–MS. Of these peaks, thymol, carvacrol, p-cymene, γ-terpinene, thymol acetate, α-caryophyllene, 3-carene, and carvacryl acetate were present at a relatively higher concentration. The results of the quantitative test showed that thymol, carvacrol, p-cymene, and γ-terpinene were the major components of the essential oil. Among the eight reference substances, only thymol, carvacrol, and thymol acetate had lower MICs compared with the essential oil. Essential oil, carvacrol, carvacryl acetate, α-caryophyllene, and 3-carene showed the better inhibition of S. aureus biofilm formation. When one fourth of the MIC concentrations were used for these substances (0.0625 mg/mL for essential oil, 0.0305 mg/mL for carvacrol, 1.458 mg/mL for carvacryl acetate, 0.1268 mg/mL for α-caryophyllene, and 2.5975 mg/mL for 3-carene), the inhibition rates were over 80%. However, thymol, γ-terpinene, thymol acetate, and p-cymene showed a relatively poor inhibition of S. aureus biofilm formation. When 1× MIC concentrations of these substances were used, the inhibition rates were less than 50%. In conclusion, Jiangxiangru essential oil and its major components, carvacrol, carvacryl acetate, α-caryophyllene, and 3-carene, strongly inhibited biofilm formation in S. aureus

E3 ligase TRIM28 promotes anti-PD-1 resistance in non-small cell lung cancer by enhancing the recruitment of myeloid-derived suppressor cells

Abstract Background Alterations in several tripartite motif-containing (TRIM) family proteins have been implicated in the pathogenesis of lung cancer. TRIM28, a member of the TRIM E3 ligase family, has been associated with tumorigenesis, cell proliferation, and inflammation. However, little is known about TRIM28 expression and its role in the immune microenvironment of non-small cell lung cancer (NSCLC). Methods We assessed the clinical significance of TRIM28 in tissue microarrays and TCGA cohorts. We investigated the function of TRIM28 in syngeneic mouse tumor models, the Kras LSL−G12D/+ ; Tp53 fl/fl (KP) mouse model, and humanized mice. Immune cell composition was analyzed using flow cytometry and immunohistochemistry. Results Our findings revealed a positive correlation between TRIM28 expression and the infiltration of suppressive myeloid-derived suppressor cells (MDSCs) in NSCLC. Moreover, silencing TRIM28 enhanced the efficacy of anti-PD-1 immunotherapy by reshaping the inflamed tumor microenvironment. Mechanistically, we demonstrated that TRIM28 could physically interact with receptor-interacting protein kinase 1 (RIPK1) and promote K63-linked ubiquitination of RIPK1, which is crucial for sustaining activation of the NF-κB pathway. Mutagenesis of the E3 ligase domain corroborated the essential role of E3 ligase activity in TRIM28-mediated NF-κB activation. Further experiments revealed that TRIM28 could upregulate the expression of CXCL1 by activating NF-κB signaling. CXCL1 could bind to CXCR2 on MDSCs and promote their migration to the tumor microenvironment. TRIM28 knockdown increased responsiveness to anti-PD-1 therapy in immunocompetent mice, characterized by increased CD8+T tumor-infiltrating lymphocytes and decreased MDSCs. Conclusion The present study identified TRIM28 as a promoter of chemokine-driven recruitment of MDSCs through RIPK1-mediated NF-κB activation, leading to the suppression of infiltrating activated CD8+T cells and the development of anti-PD-1 resistance. Understanding the regulation of MDSC recruitment and function by TRIM28 provides crucial insights into the association between TRIM28 signaling and the development of an immunosuppressive tumor microenvironment. These insights may inform the development of combination therapies to enhance the effectiveness of immune checkpoint blockade therapy in NSCLC