Sesquiterpenes and Dimeric Sesquiterpenoids from Sarcandra glabra

Two new sesquiterpenes, sarcandralactones A (1) and B (2), and five new dimeric sesquiterpenoids, sarcandrolides A-E (3-7), along with 10 known compounds were isolated from the whole plants of Sarcandra glabra. Their structures were elucidated on the basis of spectroscopic analysis. Some of the new isolates exhibit significant cytotoxicities when tested against a small panel of tumor cell lines

Interfacial interactions between protective, surface-engineered shells and encapsulated bacteria with different cell surface composition dagger

Surface-engineered encapsulation is a non-genetic method to protect living organisms against harsh environmental conditions. Different cell encapsulation methods exist, yielding shells with different interfacial-interactions with encapsulated, bacterial surfaces. However, the impact of interfacial-interactions on the protection offered by different shells is unclear and can vary for bacteria with different surface composition. Probiotic bacteria require protection against gastro-intestinal fluids and antibiotics. Here, we encapsulated two probiotic strains using ZIF-8 (zeolitic imidazolate framework) biomineralization (strong-interaction by coordinate-covalent bonding), alginate gelation (intermediate-interaction by hydrogen bonding) or protamine-assisted packing of SiO2 nanoparticles yielding a yolk-shell (weak-interaction across a void between shells and bacterial surfaces). The surface of probiotic Lactobacillus acidophilus was rich in protein, yielding a hydrophilic, positively-charged surface below and a negatively-charged one above pH 4.0. Probiotic Bifidobacterium infantis had a hydrophilic, uncharged surface, rich in polysaccharides with little proteins. Although amino groups are required for coordinate-covalent bonding of zinc and hydrogen bonding of alginate, both L. acidophilus and B. infantis could be encapsulated using ZIF-8 biomineralization and alginate gelation. Weakly, intermediately and strongly interacting shells all yielded porous shells. The strongly interacting ZIF-8 biomineralized shell made encapsulated bacteria more susceptible to antibiotics, presumably due to the cell wall damage already inflicted during Zif-8 biomineralization. Overall, weakly interacting yolk-shells and intermediately interacting alginate gels protected best and maintained probiotic activity of encapsulated bacteria. The impact of interfacial-interactions between shells and encapsulated bacteria on different aspect of protection described here, contributes to the further development of effective surface-engineered shells and its application for protecting bacteria

Metamaterial bricks and quantization of meta-surfaces

Controlling acoustic fields is crucial in diverse applications such as loudspeaker design, ultrasound imaging and therapy or acoustic particle manipulation. The current approaches use fixed lenses or expensive phased arrays. Here, using a process of analogue-to-digital conversion and wavelet decomposition, we develop the notion of quantal meta-surfaces. The quanta here are small, pre-manufactured three-dimensional units—which we call metamaterial bricks—each encoding a specific phase delay. These bricks can be assembled into meta-surfaces to generate any diffraction-limited acoustic field. We apply this methodology to show experimental examples of acoustic focusing, steering and, after stacking single meta-surfaces into layers, the more complex field of an acoustic tractor beam. We demonstrate experimentally single-sided air-borne acoustic levitation using meta-layers at various bit-rates: from a 4-bit uniform to 3-bit non-uniform quantization in phase. This powerful methodology dramatically simplifies the design of acoustic devices and provides a key-step towards realizing spatial sound modulators

Activation of a passive, mesoporous silica nanoparticle layer through attachment of bacterially-derived carbon-quantum-dots for protection and functional enhancement of probiotics

Probiotic bacteria employed for food supplementation or probiotic-assisted antibiotic treatment suffer from passage through the acidic gastro-intestinal tract and unintended killing by antibiotics. Carbon-quantum-dots (CQDs) derived from bacteria can inherit different chemical groups and associated functionalities from their source bacteria. In order to yield simultaneous, passive protection and enhanced, active functionality, we attached CQDs pyrolytically carbonized at 220 degrees C from Lactobacillus acidophilus or Escherichia coli to a probiotic strain (Bifidobacterium infantis) using boron hydroxyl-modified, mesoporous silica nanoparticles as an intermediate encapsulating layer. Fourier-transform-infrared-spectroscopy, X-ray-photoelectron-spectroscopy and scanning-electron-microscopy were employed to demonstrate successful encapsulation of B. infantis by silica nano-particles and subsequent attachment of bacterially-derived CQDs. Thus encapsulated B. infantis possessed a negative surface charge and survived exposure to simulated gastric fluid and antibiotics better than unencapsulated B. infantis. During B. infantis assisted antibiotic treatment of intestinal epithelial layers colonized by E. coli, encapsulated B. infantis adhered and survived in higher numbers on epithelial layers than B. infantis without encapsulation or encapsulated with only silica nanoparticles. Moreover, higher E. coli killing due to increased reactive-oxygen-species generation was observed. In conclusion, the active, protective encapsulation described enhanced the probiotic functionality of B. infantis, which might be considered as a first step towards a fully engineered, probiotic nanoparticle

Escherichia coli Colonization of Intestinal Epithelial Layers In Vitro in the Presence of Encapsulated Bifidobacterium breve for Its Protection against Gastrointestinal Fluids and Antibiotics

Encapsulation of probiotic bacteria can enhance their functionality when used in combination with antibiotics for treating intestinal tract infections. The interaction strength of encapsulating shells, however, varies among the encapsulation methods and impacts encapsulation. Here, we compared the protection offered by encapsulating shells with different interaction strengths toward probiotic Bifidobacterium breve against simulated gastric fluid and tetracycline, including protamine-assisted SiO2 nanoparticle yolk-shell packing (weak interaction across a void), alginate gelation (intermediate interaction due to hydrogen binding), and ZIF-8 mineralization (strong interaction due to coordinate covalent binding). The presence of encapsulating shells was demonstrated using X-ray-photoelectron spectroscopy, particulate microelectrophoresis, and dynamic light scattering. Strong interaction upon ZIF-8 encapsulation caused demonstrable cell wall damage to B. breve and slightly reduced bacterial viability, delaying the growth of encapsulated bacteria. Cell wall damage and reduced viability did not occur upon encapsulation with weakly interacting yolk-shells. Only alginate-hydrogel-based shells yielded protection against simulated gastric acid and tetracycline. Accordingly, only alginate-hydrogel-encapsulated B. breve operated synergistically with tetracycline in killing tetracycline-resistant Escherichia coli adhering to intestinal epithelial layers and maintained surface coverage of transwell membranes by epithelial cell layers and their barrier integrity. This synergy between alginate-hydrogel-encapsulated B. breve and an antibiotic warrants further studies for treating antibiotic-resistant E. coli infections in the gastrointestinal tract

Advances on relationship between phthalate exposure and perinatal depression

Perinatal depression is a psychological disorder that occurs during pregnancy and within one year of delivery, which can seriously affect the physical and mental health of pregnant and postpartum women, as well as the cognitive and behavioral abilities of offspring, with potential multigenerational effects. Therefore, it is important to identify its potential modifiable risk factors. Phthalic acid esters (PAEs), as common environmental endocrine disruptors, can affect maternal estrogen through multiple mechanisms and are important potential modifiable risk factors for developing maternal perinatal depression. At present, studies on the correlation between PAEs and perinatal depression are still very limited, and the mechanisms by which PAEs affect perinatal depression have not been clarified. Based on existing epidemiological and toxicological studies at home and abroad, the article briefly introduced the characteristics of multiple pathways, high doses, and long-term exposure to maternal PAEs, focused on reviewing the current status of epidemiological studies, pointed out the possible associations between some specific PAEs exposure and elevated risk of perinatal depression. It also summarized the potential roles of hormone-neurotransmitter pathway, inflammation mediation, gene regulation, and other possible mechanisms in the association between exposure to PAEs and perinatal depression. The article concluded with a look at how future research on the association between exposure to PAEs and perinatal depression can be scientifically validated, with a view to providing more high-quality evidence for the scientific prevention of the onset and progression of maternal depressive symptoms

Is the presence of lung injury in COVID-19 an independent risk factor for secondary lung cancer?

The morbidity and mortality of lung cancer are increasing. The Corona Virus Disease 2019 (COVID-19) is caused by novel coronavirus 2019-nCoV-2, leading to subsequent pulmonary interstitial fibrosis with chronic inflammatory changes, e.g., inflammatory factors repeatedly continuously stimulating and attacking the alveolar epithelial cells. Meanwhile, 2019-nCoV-2 can activate PI3K/Akt and ERK signaling pathways, which can play the double roles as both anti-inflammatory and carcinogenic factors. Moreover, hypoxemia may be developed, resulting in the up-regulation of HIF-1 α expression, which can be involved in the occurrence, angiogenesis, invasion and metastasis of lung cancer. Additionally, the immune system in 2019-nCoV-2 infected cases can be suppressed to cause tumor immune evasion. Therefore, we speculate that COVID-19 may be a risk factor of secondary lung cancer

Depressive symptoms in patients with irritable bowel syndrome: A meta-analysis of comparative studies

Depression is common in patients with irritable bowel syndrome (IBS), but the reported prevalence across different studies is inconsistent. This meta-analysis systematically examined the presence and severity of depressive symptoms in patients with IBS. Two investigators independently performed a literature search. The pooled depressive symptom severity was calculated using a random effects model. Subgroup, sensitivity and meta-regression analyses were conducted to examine the moderating factors of the development of depressive symptoms. Twenty four studies (n=2,837) comparing depressive symptoms between IBS patients (n=1,775) and healthy controls (n=1,062) were identified; 14 (58.3%) studies were rated as high quality. Compared to healthy controls, IBS patients had more frequent (OR=9.21, 95%CI: 4.56-18.57, P\u3c0.001; I2=76%) and more severe depressive symptoms (n=1,480, SMD=2.02, 95%CI: 1.56-2.48, P\u3c0.001; I2=94%). Subgroup analyses revealed that patients with all IBS subtypes had more severe depressive symptoms than controls. In addition, versions of the Hamilton Depression Rating Scale (HAM-D) and IBS diagnostic criteria were significantly associated with depressive symptom severity. Meta-regression analyses revealed that female gender, younger age and small sample size were significantly associated with more severe depressive symptoms. In conclusion, meta-analytic data showed that IBS patients had more frequent and severe depressive symptoms than healthy controls. Adequate screening and treatment for depression should be developed and implemented in this patient population

CTC clusters induced by heparanase enhance breast cancer metastasis.

Aggregated metastatic cancer cells, referred to as circulating tumor cell (CTC) clusters, are present in the blood of cancer patients and contribute to cancer metastasis. However, the origin of CTC clusters, especially intravascular aggregates, remains unknown. Here, we employ suspension culture methods to mimic CTC cluster formation in the circulation of breast cancer patients. CTC clusters generated using these methods exhibited an increased metastatic potential that was defined by the overexpression of heparanase (HPSE). Heparanase induced FAK- and ICAM-1-dependent cell adhesion, which promoted intravascular cell aggregation. Moreover, knockdown of heparanase or inhibition of its activity with JG6, a heparanase inhibitor, was sufficient to block the formation of cell clusters and suppress breast cancer metastasis. Our data reveal that heparanase-mediated cell adhesion is critical for metastasis mediated by intravascular CTC clusters. We also suggest that targeting the function of heparanase in cancer cell dissemination might limit metastatic progression