Surface-Enhanced Raman Spectroscopy for Identification of Heavy Metal Arsenic(V)-Mediated Enhancing Effect on Antibiotic Resistance.

Bacterial antibiotic resistance poses a threat to global public health. Restricted usage of antibiotics does not necessarily prevent its continued emergence. Rapid and sensitive screening of triggers, in addition to antibiotic, and exploring the underlying mechanism are still major challenges. Herein, by developing a homogeneous vacuum filtration-based bacterial sample fabrication enabling high surface-enhanced Raman scattering (SERS) reproducibility across multiple bacterial samples and negating interfering spectral variations from inhomogeneous sample geometry and SERS enhancement, SERS was employed to study heavy metal arsenic [As(V)]-mediated antibiotic resistance in a robust, sensitive, and rapid fashion. Independent and robust spectral changes representing phenotypic bacterial responses, combined with multivariate analysis, clearly identified that As(V) enhanced antibiotic resistance to tetracycline (Tet). Similar spectral alteration profile to As(V) and Tet indicated that cross-resistance, whereby As(V)-induced bacterial resistance simultaneously blocked Tet action, could account for the enhanced resistance. The sensitive, robust, and rich phenotypic profile provided by SERS, combined with additional advantages in imposing no need to cultivate bacteria and single-cell sensitivity, can be further exploited to evaluate resistance-intervening factors in real microbiota.

Sensitive and versatile detection of the fouling process and fouling propensity of proteins on polyvinylidene fluoride membranes via surface-enhanced Raman spectroscopy.

Membrane fouling is the major drawback of membrane-based technologies because it will lead to severe flux declines and the need to clean or replace the fouled membrane. A technique capable of early diagnosis, process monitoring, and evaluation of the role of different foulants playing in the fouling process is crucial for the fouling control. We develop surface-enhanced Raman spectroscopy (SERS) as a new and versatile tool to investigate the fouling process of protein on PVDF (polyvinylidene fluoride) membranes as well as the fouling propensity of three different proteins. We optimized the aggregation level and volume of SERS-active Ag sol and the spectra acquisition method combined with a statistical analysis method to ensure a high detection sensitivity, signal uniformity, and stability. We then used SERS for the early diagnosis of the fouling process and determining when the membrane pores would be blocked. The fouled area was visualized by a combination of the silver staining and Raman mapping. The fouling propensity of different proteins was studied by comparing the relative SERS band intensities of different proteins on a glass slide and after membrane filtration. Compared with fluorescence-based techniques, the narrow, well-resolved Raman band, especially the use of the same excitation line and laser power, endows SERS the ability to compare the fouling propensity in a very simple way.

Flocculation performance of a novel synthesized flocculant with low ecological risk.

Combined flocculants with low ecological risk are urgently required in water supply and wastewater treatment in China. A novel flocculant was thus developed under the condition of low ecological risk (noted as CAS). The experiments to examine wastewater treatment performance of the new product showed that there was favourable performance in the flocculation process in contrast to commercial flocculants in treating kaolin suspensions, municipal effluent and domestic wastewater. Flocculation performance included the turbidity removal rate, sediment character and a decrease in COD (chemical oxygen demand). The sediment time of flocculation is short and the removal rate of turbidity treated by CAS is high compared with PAC (polyaluminum-chloride), PAM (polyacrylamide) and the combined addition of PAC and PAM. The optimal concentration required to affect flocculation processes is dependent on kaolin concentration and the character of the wastewater within the range examined. It also showed that CAS is effective to treat wastewater with high turbidity.

[Clinical observation of acupoint sticking therapy with Xiongbai Qianlie powder in the treatment of type III prostatitis syndrome].

OBJECTIVE: To compare the efficacy difference between acupoint sticking therapy and the combined therapy of retention-enema and millimeter-wave radiation in the treatment of type III prostatitis syndrome. METHODS: Seventy-two cases were randomized into an acupoint sticking therapy group (group A, 36 cases) and an enema group (group B, 36 cases). The acupoint sticking therapy with Xiongbai Qianlie powder was applied to Ciliao (BL 32), Zhongji (CV 3), Guanyuan (CV 4), Huiyin (CV 1) and Changqiang (GV 1) in group A. The retention-enema with Ruyi Jinhuang powder plus millimeter-wave radiation at the prostatic region was used in group B. Eight treatments made one session. Totally, 2 sessions of treatment were required. The score of the symptoms of chronic prostatitis (NIH-CPSI) and the efficacy were observed. RESULTS: Of 36 cases in group A, 5 cases were dropped off, 13 cases remarkably effective, 17 cases effective and 1 case failed; the total effective rate was 96.8% (30/31). Of 36 cases in group B, 7 cases were dropped off, 7 cases remarkably effective, 17 cases effective and 5 cases failed; the total effective rate was 82.7% (24/29). The efficacy in group A was much better (P < 0.05). After the treatment, the score of NIH-CPSI was reduced obviously in either group (both P < 0.01). The result in group A was much better than group B (P < 0.05). CONCLUSION: The acupoint sticking therapy with Xiongbai Qianlie San achieves a good efficacy on type III prostatitis syndrome and its efficacy is superior to the retention-enema plus millimeter-wave radiation therapy.