Effects and molecular mechanism of sugar transporter ESA_RS15745 on desiccation resistance, motility, and biofilm formation of Cronobacter sakazakii.

Cronobacter sakazakii, an important Gram-negative foodborne pathogen, can cause neonatal meningitis and sepsis with high rates of infection and death. Gene ESA_RS15745 encodes a sugar transporter protein, which is not only essential for osmotic pressure maintenance during bacterial growth and reproduction but also associated with their desiccation tolerance, motility, and biofilm formation. Here, a mutant strain of ESA_RS15745 (ΔESA_RS15745) and the complementation strain (cpESA_RS15745) were constructed using a suicide vector knockout and gene complementation. ΔESA_RS15745 was found to have a decrease in its ability to transport maltose and trehalose and resist desiccation, whereas an increase in the ability of motility and biofilm formation, implying that ESA_RS15745 may positively regulate sugar transport and desiccation tolerance and negatively regulate motility and biofilm formation. To further investigate the molecular mechanisms underlying the function of related genes, RNA-seq was performed to explore the differentially expressed genes in the mutants. RNA-seq results showed the upregulation of 114 genes (mainly including those regulating chemotaxis and flagellar motility) and the downregulation of 22 genes (mainly including those regulating sugar transport). qRT-PCR analysis supported the RNA-seq results and showed that ESA_RS15745 may influence the dehydration tolerance though decreasing the intracellular trehalose content and negatively regulate the motility though the chemotactic signaling pathway. In addition, the biofilm formation of C. sakazakii should also be speculated to negatively regulate by ESA_RS15745 by consuming the extracellular carbohydrates concentration and then downregulating the intracellular cyclic diguanosine monophosphate. This study offers a reference for comprehending the molecular mechanism of gene ESA_RS15745 in C. sakazakii.

Preliminary observation of the blocking effect produced by injecting polyacrylamide hydrogel on low hydraulic resistance channel along meridian / 生物医学工程学杂志

To study the role of meridians in the formation and development of diseases, a pathological model of obstructed channel was established by injecting polyacrylamide hydrogel. The effects of blocking low hydraulic resistance channel (LHRC), produced by injecting polyacrylamide hydrogel and by injecting normal saline, were compared by examining the change in transmission of interstitial fluid pressure wave. The results showed that there was significant decrease (P < 0.01) in interstitial fluid pressure wave after more than 0.5 ml polyacrylamide hydrogel was injected into the channel, whereas no significant changes were found after normal saline was injected or when the hydrogel was outside the channel. The above findings demonstrate that the low hydraulic resistance channel can be blocked by injecting certain amount of polyacrylamide hydrogel and a pathological model of obstructed channel has been established preliminarily.

Influence of Mechanical Pressure to Change of Transcutaneous CO2 Emission by Acupuncture / 针灸推拿医学（英文版）

Objective: In the authors' previous study, acupuncture had an effect along meridians. The effect ofacupuncture can be represented by local energy metabolism which can be expressed by transcutaneous CO2 emission (TCE). To study the transportation of the effect of acupuncture and the influence to the transportation when blocking the meridians, the following experiment was carried out. Methods: Twenty healthy volunteers (male 8, female 12, average age 29) were examined on pericardium meridian at points between Quze (PC 3) and Tianquan (PC 2) (Point a), between Ximen (PC 4) and Quze (PC 3) (Point b), two control points (c and d) beside a and b and Quze (PC 3). TCE was measured on these five points before, during and after acupuncturing Neiguan (PC 6) by a high sensitive CO2 instrument (Frewil-Q.F., made in China). Mechanical pressure of 1 kg (2 cm～ 1 cm area) was given on Ximen (PC 4) or Daling (PC 7) during the acupuncture and TCE were measured before acupuncture, during acupuncture and mechanical pressing, withdrawing acupuncture but keeping pressing and after withdrawing the pressure. Results: TCE increased significantly on point a, b and Quze (PC 3) during and after acupuncture without mechanical press. When mechanical press was given at Ximen (PC 4), no significantly increase was found on above three points during and after acupuncture. When pressing Daling (PC 7), there was still significant (P<0.05) increase at Quz～ (PC 3) and point during acupuncture and significant increase (P<0.05) at point b after acupuncuture while pressing was kept. Conclusion: Acupuncture can enhance the energy metabolism expressed by TCE along meridians and this effect can be eliminated by mechanical pressing along meridians on the way between acupuncture point and measured point.

Influence of Different Acupuncture Method on Points Transcutaneous CO2 Emission / 针灸推拿医学（英文版）

Objective: To observe the influence of transcutaneous CO2emission (TCE) at points on the meridian or beside the meridian after different stimulations like acupuncture De-qi, sham acupuncture, study the correlation between acupuncture De-qi and local energy metabolism through TCE. Methods: Twenty healthy volunteers (male 8, female 12, average age 29 years old) were selected. Before, during and after five different acupuncture Neignan (PC 6), the TCE was measured at Quze (PC 3), point A [at the lower one fourth of line between Tianquan (PC 2) and Quze (PC 3)], point B [at the middle of line between Ximen (PC 4) and Quze (PC 3)], point C (2 cm ulnar side point A) and point D (2 cm ulnar side point B) with a high sensitive C02 instrument (Frewil-Q.F., made in China). The measure results were compared. Results: The comparison on value of TCE before and after the acupuncture, in Sham acupuncture and shallow acupuncture groups, it increased in all five points; in De-qi acupuncture group, there are significant increase on point A, point B, and Quze (PC 3), it has statistic significance, but there are no significant increase on point C and D. After Ximen (PC 4) or Daling (PC 7) were pressed to block Neiguan (PC 6), the value of TCE on Quze (PC 3), point A and point B were decreased during acupuncture Neiguan (PC 6), and increased after the block was removed, but there was no significant difference. Conclusion: Sham acupuncture has also some effects on body, it can increase energy metabolism of local skin, it may be the reason that shallow acupuncture without qi amving can obtain clinical efficacy. The operation method of traditional qi arriving acupuncture can increase energy metabolism of relevant meridian skin, mechanical press can reduce this effect.