Frontiers in bioscience (Scholar edition)最新文献

Background: Pulsed ultraviolet (UV) irradiation can be used to generate a broad UV-C spectrum. The pulsing nature of such a spectrum helps increase the damage to cancer cells, leading to their injury and death. In contrast, non-tumor cells repair the damage and survive the same pulsed UV irradiation energy. Herein, we describe the development of a pulsed UV irradiation method for cancer cell dysfunction that irradiates cells with pulsed light by generating tremendous instantaneous UV energy-tens of thousands of times greater than that generated by UV lamps-to cause specific cell injury and dysfunction of cancer cells.

Methods: A newly developed pulsed ultraviolet irradiation device was used. Features of the device used in this study. This device employs a quartz discharge xenon lamp. Cultured tumor cells and non-tumor cells were irradiated with pulsed light at different irradiation doses, and their reactions were observed using optical, electron, and laser microscopes.

Results: Cancer cells have more FAS (CD95) receptor domains than non-cancer cells, and pulsed UV irradiation stimulates the production of reactive oxygen species (ROS) and OH, which exceeds the oxidative stress removal function, resulting in cell injury and death. That is, at low UV doses, only cancer cells underwent cell death, whereas non-cancer cells did not. The pulsed UV irradiation technique directly destroys cancer cells and minimizes the number of residual cancer cells while allowing minimum invasion into non-tumor cells, thereby improving their survival. This suggests the possibility of activating the host's local immune response to eliminate residual cancer cells.

Conclusions: A newly developed pulsed UV radiation system shows potential for use in the development of a drug-free cancer treatment system that selectively kills tumor cells by irradiating them with high-intensity pulsed UV rays over a broad UV-C range of 230-280 nm.

Nosocomial infections pose an imminent challenge to hospitalized Coronavirus disease-19 (COVID-19) patients due to complex interplay of dysregulated immune response combined with immunomodulator therapy. In the pre-pandemic era, immunomodulatory therapy has shown benefit in certain autoimmune conditions with untamed inflammatory response. Efforts to recapitulate these immunomodulatory effects in COVID-19 patients has gained impetus and were followed by NIH COVID-19 expert panel recommendations. The current NIH guideline recommends interleukin-6 inhibitors (tocilizumab and sarilumab) and Janus kinase inhibitors (baricitinib and tofacitinib). Several landmark research trials like COVAVTA, EMPACTA, REMDACTA, STOP-COVID and COV BARRIER have detailed the various effects associated with administration of immunomodulators. The historical evidence of increased infection among patients receiving immunomodulators for autoimmune conditions, raised concerns regarding administration of immunomodulators in COVID-19 patients. The aim of this review article is to provide a comprehensive update on the currently available literature surrounding this issue. We reviewed 40 studies out of which 37 investigated IL-6 inhibitors and 3 investigated JAK inhibitors. Among the studies reviewed, the reported rates of nosocomial infections among the COVID-19 patients treated with immunomodulators were similar to patients receiving standard of care for COVID-19. However, these studies were not powered to assess the side effect profile of these medications. Immunomodulators, by dampening the pyrogenic response and inflammatory markers may delay detection of infections among the patients. This underscores the importance of long-term surveillance which are necessary to discover the potential risks associated with these agents.

Background: Carbohydrate digestive enzymes play a major role in the management of the postprandial hyperglycemia. A chronic hyperglycemia can lead to serious health problems due to excessive production of several reactive oxygen species. Therefore, the inhibition of carbohydrate digestive enzyme and the use of antioxidant natural product can be an important strategy to control the glycaemia level and prevent against the complication of diabetes.

Aim: The study aims to perform a phytochemical analysis, antioxidant activity, inhibitory effect on α -amylase, α -glucosidase (in vitro and in vivo) and the intestinal glucose absorption in Wistar rats of Artemisia campestris aqueous extract (AcAE) and hydro-ethanolic extract (AcEE).

Results: The test of total phenolic content, show that the AcAE has the highest quantity of polyphenol (44.65 ± 0.54 μ g GAE/mg extract) compared to the AcEE (31.7 ± 0.53 μ g GAE/mg extract) significantly. The amount of flavonoid and condensed tannins content in AcAE is 24.41 ± 3.57 μ g QrE/mg extract, 14.31 ± 5.26 μ g CE/mg respectively. The AcAE has also exhibit a great antioxidant activity in DPPH-scavenging and Ferric reducing antioxidant power assay (FRAP) compared to AcEE with an IC 50 = 0.355 ± 0.057 mg/mL and IC 50 = 0.269 ± 0.025 mg/mL. However, in a β -carotene bleaching assay the AcEE has the highest effect with an IC 50 = 0.319 ± 0.097 mg/mL. The both extract of Artemisia campestris L. (250 mg/kg) decreased postprandial hyperglycemia in the normal and alloxane diabetic rats in a very significant manner after starch or sucrose administration as an α -amylase and α -glucosidase substrate respectively. This result is confirmed in vitro by a remarkable inhibitory effect on α -amylase digestive enzymes by an IC 50 = 1.259 ± 0.128 mg/mL and IC 50 = 0.602 ± 0.072 mg/mL receptively for AcAE and AcEE. For the α -glucosidase enzyme, the both extracts significantly inhibit α -glucosidase activity compared to the control and they are almost similar to each other. Using a jejunum perfusion technique (in situ), Artemisia campestris L. decrease the intestinal D-glucose absorption activity significantly compared to the control and comparable to the Phlorizin used as a positive control by an amount of glucose absorbed equal a 6.53 ± 0.57, 5.34 ± 0.64 and 4.71 ± 0.24 mg/10 cm/h, for AcAE, AcEE and Phlorizin respectively.

Conclusions: These results showed that the Artemisia campestris L. has highest phenolic content, antioxidant activity and demonstrated a postprandial anti-hyperglycemic effect via the inhibiting of the carbohydrate digestive enzyme ( α -amylase and α -glucosidase) and the intestinal glucose absorption.

The main entry point of SARS-CoV-2 is the respiratory tract and as such immune defence in this site determines if the virus will spill-over to the systemic circulation and circulate and infect other major organs. The first line of mucosal immune defence is composed of mucins, an epithelial barrier, and immune cells in the nasal cavity. The lung immune defence is carried out by numerous alveoli. The lung microbiota is a key factor in determining the efficacy of lung mucosal immunity protection. The intestinal microbiota has been demonstrated to affect the severity of COVID-19. Gut dysbiosis is involved in hyperinflammation and multiple organ failure through communications with multiple organs. The gut lung axis could be the earliest axis affected in COVID-19. Through the gut-lung axis, gut dysbiosis can affect the pathogenesis of the lung in COVID-19. In this review, we summarise the effects that gut dysbiosis can progress on the lung, and the lung microbiota. The possible mechanisms and approaches for modulation are discussed.

Alzheimer's disease (AD) is the most common neurodegenerative disorder, resulting in memory loss, cognitive decline, bodily function impairment, and finally death. The growing number of people suffering from AD increasingly urges the development of effective early diagnosis and monitoring techniques. Here, we review the most recent developments in the field of Raman-based techniques, which have shown a significant potential in identifying AD by detecting specific biomarkers in biological fluids, as well as in providing fundamental insights into key molecules involved in the disease progression or in the analysis of histological specimens of patients with AD. These techniques comprise spontaneous and resonant Raman spectroscopies, exploit plasmon- or fiber- enhanced effects, such as surface-, tip- or fiber- enhanced Raman spectroscopies, or involve non-linear techniques like coherent Raman scattering. The scientific efforts employed up to now as well as the rapid technological advancements in optical detection instruments (spectrometers, lasers, substrates for analysis, etc.) and the diffusion of advanced data processing methods suggest a leading role of Raman techniques in the perspective of a preclinical or clinical detection of AD.

The most frequent arrhythmia treated is atrial fibrillation (AF), which necessitates the use of oral anticoagulants (OACs) to reduce the risk of thromboembolism and stroke. Patients with chronic kidney disease are more likely to develop AF, with a 10% frequency among those on chronic dialysis. Warfarin is the most widely prescribed OAC for individuals with end-stage kidney disease (ESKD). On the other hand, direct OACs (DOACs) are generally safer than warfarin, with fewer fatal bleeding events and a fixed dose that does not require close international normalized ratio (INR) monitoring. For those patients, warfarin and apixaban appear to be FDA-approved, whereas dabigatran, rivaroxaban, and edoxaban are not recommended yet. Due to a lack of large randomized studies, data from major trials cannot be extended to dialysis patients. In this review, we summarize the available data and literature referring to patients on chronic hemodialysis with concomitant AF. Due to the scarcity of data, we try to assist clinicians in selecting the appropriate therapy according to the specific characteristics of each patient. Finally, future directions are provided in two key areas of focus: left atrial appendage closure therapies and genetic research.

Gestational diabetes (GDM) is quite common during pregnancy, and its prevalence is rising because of the increased overweight and obesity rates. In patients with GDM, proper glycemic control, adherence to a suitable diet and antidiabetic treatments can reduce the likelihood of maternal-neonatal complications. For this reason, this study aims to assess the therapy adherence of pregnant women with GDM. Treatment adherence was assessed by both glucometer and diabetologist's analysis reported in the electronic medical record. Cohen's Kappa was used to assess the agreement between the two classifications. Moreover, a multivariate logistic regression analysis was performed to identify potential risk factors for non-adherence to treatment. Overall, 287 patients were enrolled, and 271 were available for follow-up. Low concordance between the glucometer and the diabetologist's analysis was found, mainly due to the complexity of patients with GDM. Indeed, 46% of patients were classified as not adherent due to glucometer results and 42% based on medical assessment. This study highlights the importance of monitoring patients with gestational diabetes to assess and increase adherence to therapy properly.

Background: Stress-inducible heat shock protein 70 (HSP70) is both a protective chaperone involved in protein homeostasis and an immune regulator. In both capacities, HSP70 has been implicated in muscle disorders, yet with fragmented and differing results. In this study we aimed to compare results obtained in the mouse model for the severest form of muscular dystrophy (MD) equivalent to Duchenne MD, termed the mdx mouse, with results obtained in human MD.

Methods: Skeletal muscle and serum samples were obtained from 11 healthy controls, 11 fully characterized patients diagnosed with Becker MD and limb girdle MD (LGMD), and six muscle disease controls. In addition, muscle extracts were prepared from tibialis anterior of mdx and control mice at ages 4, 8 and 12 weeks. The HSP70 levels were quantified using RT-PCR, western blotting and protein arrays, and localized in muscle tissue sections using double immunofluorescence.

Results: We found selective and significant 2.2-fold upregulation of HSP70 protein in mdx tibialis muscle at the earliest disease phase only. In LGMD and Becker MD patients, HSP70 protein levels were not significantly different from those of healthy muscle and serum. HSP70 was localized to regenerating muscle fibers both in mouse and human MD skeletal muscle tissues. Toll-like receptor (TLR) 2 and TLR4 expression was moderately increased on the sarcolemma in MD muscle, yet protein levels were not significantly different from normal controls.

Conclusions: HSP70 upregulation in MD appears disease stage-dependent, marking the phase of most active muscle regeneration in the mdx mouse. We postulate that well-timed supportive therapeutic interventions with HSP70 agonists could potentially improve muscle tissue's regenerative capacities in MD, attenuating loss of muscle mass while we await gene therapies to become more widely available.

Mesial roots and isthmuses of mandibular molars are difficult areas to obtain adequate disinfection of root canal walls, and consequently microorganisms can survive treatment. The present study compared, through real-time polymerase chain reaction (qPCR), the effectiveness of TRUShape (TS) (Dentsply Tulsa Dental Specialties, Tulsa, OK) and Vortex Blue (VB) (Dentsply Tulsa Dental Specialties, Tulsa, OK) in removing Enterococcus faecalis (E. faecalis) from the mesial canals and isthmuses of mandibular molars. Fifty extracted human lower molars were inoculated with E. faecalis OG1RF for 14 days, and then an initial bacterial sample was collected with paper points from mesiobuccal and mesiolingual canals and isthmuses. The specimens were randomly divided into four groups (n = 10 teeth; 20 canals each), according to instrumentation system: TS 25/0.06, TS 30/0.06, VB 25/0.06 and VB 30/0.06. The remaining 10 teeth were divided between positive control, inoculated teeth without instrumentation or irrigation, and negative controls, teeth without inoculation. After instrumentation, the final sample was taken using paper points and DNA was isolated. Primers specific for E. faecalis were used for qPCR. The bacterial reduction between pre- and post-instrumentation was calculated. One-way analysis of variance (ANOVA) with Bonferroni's multiple-comparisons tests were for statistical analysis with significance of (p < 0.05). All file systems were able to reduce the load of E. faecalis from the prepared root canals, however, TS size 30 removed significantly more bacteria than size 25. Interestingly, regardless of the size, TS files removed significantly more E. faecalis biofilm (p < 0.05) than did VB files (63.7% vs 50.8% for size 25, and 69.5% vs 56% for size 30). In conclusion, when combined with irrigation, TS file system is more effective than VB in reducing E. faecalis biofilms from mesiobuccal and mesiolingual canals and the isthmuses of mandibular molars.