Synergistic effect of kanamycin and amikacin with setomimycin on biofilm formation inhibition of Listeria monocytogenes.

Listeria monocytogenes, a foodborne pathogen that causes listeriosis with high fatality rate, exhibits multidrug resistance (MDR) known to be progressively increasing. Alternative antibacterial strategies are in high demand for treating this well-known pathogen. Anti-biofilm and anti-virulence strategies are being explored as novel approaches to treat bacterial infections. In this study, one rare antibacterial named setomimycin was isolated from Streptomyces cyaneochromogenes, which showed potent antibacterial activity against L. monocytogenes. Next, the inhibition of biofilm formation and listeriolysin O (LLO) production against L. monocytogenes were investigated at sub-minimal inhibitory concentrations (sub-MICs) of setomimycin alone or combined with kanamycin and amikacin. Crystal violet staining confirmed that setomimycin combining with kanamycin or amikacin could dramatically reduce biofilm formation against L. monocytogenes at sub-MICs, which was further evaluated by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). In the meantime, sub-MICs of setomimycin could significantly suppress the secretion of LLO. Furthermore, the transcription of genes associated with biofilms and main virulence factors, such as LLO, flagellum, and metalloprotease, were suppressed by setomimycin at sub-MICs. Hence, the study provided a deep insight into setomimycin as an alternative antibacterial agent against L. monocytogenes.

2-Hydroxymethyl-1-methyl-5-nitroimidazole, one siderophore inhibitor, occludes quorum sensing in Pseudomonas aeruginosa.

Siderophore is necessary for the survival of microorganisms and is interregulated with quorum sensing (QS) systems. It is related to growth, proliferation, virulence, and other bacterial social activities as a virulence factor. Thus, we speculated that the QS system could be occluded by inhibiting siderophore production. 2-Hydroxymethyl-1-methyl-5-nitroimidazole (HMMN), one siderophore inhibitor of Pseudomonas aeruginosa PAO1 (P. aeruginosa PAO1), was obtained by using the Chromeazurol S (CAS) method. We found that HMMN inhibited siderophore production and influenced the biological effects of QS regulation, including biofilm formation and pyocyanin production. HMMN (150 µg/ml) inhibited the siderophore production of P. aeruginosa PAO1 by 69.37%. In addition, HMMN could inhibit pyocyanin production and biofilm formation and erase the formed biofilm of P. aeruginosa PAO1. HMMN (150 µg/ml) inhibited the biofilm formation of P. aeruginosa PAO1 by 28.24%. The erasure rate of the formed biofilm reached 17.03%. Furthermore, HMMN (150 µg/ml) inhibited P. aeruginosa PAO1 pyocyanin production by 36.06%. Meanwhile, positive-control hordenine (500.0 µg/ml) reduced the biofilm formation and pyocyanin production of P. aeruginosa PAO1 by 14.42% and 34.35%, respectively. The erasure rate of hordenine to the formed biofilm is 11.05% at 500 µg/ml. Quantitative real-time polymerase chain reaction (qRT-PCR) showed that HMMN downregulates not only siderophore-related genes but also QS-related genes, as well as hordenine. These results suggest that a siderophore inhibitor could be used as a QS inhibitor to occlude the QS system and reduce virulence.

Actinomycin D: a novel Pseudomonas aeruginosa quorum sensing inhibitor from the endophyte Streptomyces cyaneochromogenes RC1.

The infections caused by Pseudomonas aeruginosa are difficult to treat due to its multidrug resistance. A promising strategy for controlling P. aeruginosa infection is targeting the quorum sensing (QS) system. Actinomycin D isolated from the metabolite of endophyte Streptomyces cyaneochromogenes RC1 exhibited good anti-QS activity against P. aeruginosa PAO1. Actinomycin D (50, 100, and 200 µg/mL) significantly inhibited the motility as well as reduced the production of multiple virulence factors including pyocyanin, protease, rhamnolipid, and siderophores. The images of confocal laser scanning microscopy and scanning electron microscopy revealed that the treatment of actinomycin D resulted in a looser and flatter biofilm structure. Real-time quantitative PCR analysis showed that the expression of QS-related genes lasI, rhlI, rhlR, pqsR, pslA, and pilA were downregulated dramatically. The production of QS signaling molecules N-(3-oxododecanoyl)-L-homoserine lactone and N-butanoyl-L-homoserine lactone were also decreased by actinomycin D. These findings suggest that actinomycin D, a potent in vitro anti-virulence agent, is a promising candidate to treat P. aeruginosa infection by interfering with the QS systems.

Analysis of transcriptome difference between rapid-growing and slow-growing in Penaeus vannamei.

Penaeus vannamei is the principle cultured shrimp species in China. However, with the increase of culture density, the growth difference between individuals is also expanding. Here, we make use of RNA-seq to study the growth mechanisms of P. vannamei. After 120 days, we examined the transcriptomes of rapid-growing individuals (RG) and slow-growing individuals (SG). A total of 2116 and 176 differentially expressed genes (DEGs) were found in SG and RG, respectively. Moreover, the main DEGs are opsin, heat shock protein (HSP), actin, myosin, superoxide dismutase (SOD), cuticle protein, and chitinase. GO analysis further revealed that the DEGs were enriched in biological processes significantly, such as "sensory perception," "sensory perception of light stimulus," "response to stimulus," and "response to stress." Additionally, KEGG enrichment analysis showed that the DEGs were mainly enriched in "pentose and glucuronate interconversions," "amino sugar and nucleotide sugar metabolism," "glycophospholipid biosynthesis," and "glutathione metabolism." Interestingly, the upstream genes in the ecdysone signaling pathway, including molting inhibition hormone (MIH) and crustacean hyperglycemic hormone (CHH), did not differ significantly between RG and SG, which suggests that the cause for the inconsistent growth performance is due to the stress levels rather than the ecdysone signal pathway. In summary, this work provides data that will be useful for future studies on shrimp growth and development.

Is preemptive analgesia a good choice for postoperative pain relief in lumbar spine surgeries?: A meta-analysis of randomized controlled trials.

BACKGROUND: Lumbar spine surgery is associated with moderate-to-severe postoperative pain. Adequate pain management during the postoperative period facilitates rehabilitation. Recently, preemptive analgesia has been considered among the important analgesic methods for reducing postoperative pain. However, its efficacy in postoperative pain relief after lumbar spine surgery remains unclear. This study aimed to evaluate the effects of preemptive analgesia on lumbar spine surgery. METHODS: We searched for randomized controlled trials in PubMed (1996 to May 2020), Embase (1980 to May 2020), and Cochrane Library (CENTRAL, May 2020). We included seven studies that evaluated the preemptive analgesic efficacy in lumbar spine surgeries. RESULTS: Seven studies, including 509 patients, met the inclusion criteria. Pooled data revealed that preemptive analgesia is effective for lumbar spine surgeries with respect to the visual analog scale score (P < .05), total morphine equivalent consumption (P < .05), and length of stay (P < .05), without increasing complications (P = .73). CONCLUSIONS: Our findings indicate that preemptive analgesia is safe and effective for lumbar spine surgery.

Characterization and chemical modification of PLN-1, an exopolysaccharide from Phomopsis liquidambari NJUSTb1.

Phomopsis liquidambari is a classical endophytic fungus with great application potential in ecology and agriculture; however, studies on its exopolysaccharides are lacking. Here, we aimed to evaluate the structure and bioactivity of PLN-1, an exopolysaccharide derived from the P. liquidambari NJUSTb1 strain. The structure was elucidated by chromatography/spectral methods and hydrolyzation. Immunomodulation, moisture absorption, and retention properties were investigated after sulfation and carboxymethylation modification. Results showed that PLN-1 contained a linear repeating unit of →[4)-α-d-Glcp-(1→6)-α-d-Glcp-(1→4)-α-d-Glcp-(1→4)-α-d-Glcp-(1→]n, with a molecular weight of 343 kDa. The degrees of substitution of sulfated polysaccharide (S-PLN-1) and carboxymethylated polysaccharide (C-PLN-1) were 1.228 and 0.903, respectively. S-PLN-1 showed stronger moisture absorption and retention properties than PLN (crude EPS), C-PLN1, and PLN-1. Furthermore, PLN, S-PLN-1, and C-PLN-1 stimulated the proliferation of RAW 264.7 cells with no cytotoxicity. The elucidation of PLN-1 in this study paves the way for future applications.

Is the proximal adductor canal block a better choice than the distal adductor canal block for primary total knee arthroplasty?: A meta-analysis of randomized controlled trials.

BACKGROUND: Total knee arthroplasty is accompanied by moderate to severe postoperative pain. Postoperative pain hampers the functional recovery and lowers patient satisfaction with the surgery. Recently, the adductor canal block (ACB) has been widely used in total knee arthroplasty. However, there is no definite answer as to the location of a continuous block within the ACBs. METHOD: Randomized controlled trials about relevant studies were searched in PubMed (1996 to Oct 2019), Embase (1996 to Oct 2019), and Cochrane Library (CENTRAL, Oct 2019). RESULTS: Five studies involving 348 patients met the inclusion criteria. Pooled data indicated that the proximal ACB was as effective as the distal ACB in terms of total opioid consumption (P = .54), average visual analog scale (VAS) score (P = .35), worst VAS score (P = .19), block success rate (P = .86), and time of catheter insertion (P = .54). CONCLUSIONS: Compared with the distal ACB, the proximal ACB showed similar analgesic efficacy for total opioid consumption, average VAS score, worst VAS score, block success rate, and time of catheter insertion. However, because of the limited number of involved studies, more high-quality studies are needed to further identify the optimal location of the ACB.

Comparison of adductor canal block with periarticular infiltration analgesia in total knee arthroplasty: A meta-analysis of randomized controlled trials.

BACKGROUND: Total knee arthroplasty (TKA) is accompanied by moderate to severe postoperative pain. Multimodal analgesia, such as femoral nerve block, periarticular infiltration analgesia (PIA), and patient-controlled intravenous analgesia, have been used for postoperative analgesia. Recently, randomized controlled trials have compared the efficacy of the adductor canal block (ACB) and the PIA in patients undergoing TKA. However, there is no definite answer as to the efficacy and safety of the ACB compared with the PIA. METHOD: Randomized controlled trials about relevant studies were searched from PubMed (1996 to May 2019), Embase (1980 to May 2019), and Cochrane Library (CENTRAL, May 2019). Five studies which compared the ACB with the PIA methods were included in our meta-analysis. RESULTS: Five studies containing 413 patients met the inclusion criteria. There were no significant differences between the ACB and the PIA group in visual analog scale (VAS) score at rest (P = .14) and movement (P = .18), quadriceps muscle strength (P = .95), complications (P = .78), length of stay (LOS) (P = .54), and time up and go (TUG) test (P = .09), While patients in the ACB group had less equivalent morphine consumption (P < .05) compared with the PIA group. CONCLUSIONS: Our pooled data indicated the ACB group reduced the equivalent morphine consumption compared with the PIA group, with no statistically significant differences in the VAS score, quadriceps muscle strength, TUG test, complications, and LOS.

[Case-clinical studies on three different intervertebral fusion with bone graft and internal fixation in the treatment of cervical spondylotic myelopathy].

OBJECTIVE: To evaluate the therapeutic effects of three different intervertebral fusion with bone graft and internal fixation in the treatment of cervical spondylotic myelopathy. METHODS: In the retrospective study, 83 patients (38 males and 45 females, with an average age of 69 years) with cervical spondylotic myelopathy were divided into three groups. The patients in three groups were treated by autogenous iliac bone grafting (Robingson grafting) with anterior cervical plate-screw fixation, Pyramesh with anterior cervical plate-screw fixation and BAK fixation respectively. JOA scores and the bony fusion time were recorded and the results were evaluated by numeric computer system. RESULTS: The JOA scores of all the patients were higher than those before surgery (t = 1.55, P < 0.05). There were no statistical difference of JOA scores in the three groups (F = 2.51, P > 0.05). CONCLUSION: It is concluded that internal fixation of the three types is promising to the treatment of cervical spondlotic myelopathy. Robingson grafting with anterior cervical plate-screw fixation provides good stability and bony fusion. BAK is better technically required but there was height loss in clinic. Pyramesh with anterior cervical plate-screw fixation combines the merits of both two techniques above but the cost is higher.

[Prevalence of chronic prostatitis and its effects on male infertility].

OBJECTIVE: To investigate the prevalence of chronic prostatitis (CP) in male infertility patients and its effects on male infertility. METHODS: 534 male patients with complaints of male infertility were interviewed for the history of prostatic disease and underwent digital rectal examination of prostate, analysis of semen and express prostatic secretions (EPS). Bacterial culture of urine was done in 40 randomly selected inflammatory CP patients by pre- and post-message method (pre- and post-massage test, PPMT). RESULTS: 209 out of the 534 patients with male infertility were diagnosed as chronic prostatitis with a prevalence rate of 39.1%, among which 46 with CP type II and IIIA with the prevalence rate of 8.6%, 28 with CP type IIIB (5.2%), and 135 with CP type IV (25.3%) respectively. Positive bacterial culture was found in 10 out of the 40 cases of inflammatory chronic prostatitis (25.0%). The bacterial infection rate was 24.2% (8/33) in the cases of CP type IV. The prevalence rate of liquefaction dysfunction was much higher in the patients of male infertility with CP (22.7%) than in those without CP (14.3%, P < 0.05), however, it had little influence on the quality of semen, pH value, sperm density, and sperm motility. CONCLUSION: Quite common in patients with male infertility, CP prolongs the time of liquefaction, but has no other reverse influence on semen.

[A tentative research of testosterone supplement therapy on male senile dementia].

OBJECTIVES: To understand the hormone levels in male senile dementia patients and the effects of testosterone supplement theraphy (TST) on male senile dementia. METHODS: The general health condition, mental health condition, hormone levels, and some other aspects were evaluated in 9 patients with male senile dementia without significant contradiction for TST. 9 patients were treated with oral testosterone undecanoate 120 mg per day for six weeks, and relative changes were observed, detected and recorded. RESULTS: In 9 cases of male senile dementia, the average score was 5.33 in mini-mental state examination (MMSE), 14.56 in Hamilton depression scale (HAMD), 5.0 in geriatric depression scale (GDS), 32.56 in partial androgen deficiency of the aging male (PADAM) measuring form. The volume of testis was small (8.33 ml on average). After 1 week of having finished TST, the levels of serum testosterone (T) dropped significantly (dropped from average 2.88 ng/ml to 2.47 ng/ml, P < 0.05) in 9 patients with TST. General evaluation with clinician's global impression(CGI) for 9 patients showed 2 cases fail and 7 cases with progress (3 of them progress significantly). Average score dropped in HAMD form (10.67) and PADAM form (28.11). Physical strength and psychological status improved significantly, but vasomotor symptoms and sexual function failed response to the treatment. CONCLUSIONS: The levels of androgen is low, and the symptoms of androgen deficiency are readily seen in male senile dementia. TST can improve life quality of most patients to some extent.

[Investigation of chronic prostatitis and altered bowel habits].

OBJECTIVES: To explore the incidence, causes, and significance of altered bowel habits in chronic prostatitis. METHODS: Investigating the incidence of altered bowel habits in chronic prostatitis, analyzing some possible causes to induce the symptom, such as course of disease, vegetative nerve functional disturbance, inflammation in expressed prostatic secretions, and digital rectal examination. Following up the improvement of altered bowel habits after effective treatment of chronic prostatitis. RESULTS: The incidence of altered bowel habits was 31.40% in 379 chronic prostatitis patients. The detected congestion and swelling of prostate was closed related to altered bowel habits in chronic prostatitis. The incidence of improvement of altered bowel habits after effective treatment of chronic prostatitis reached to 78.79%. CONCLUSIONS: Congestion and swelling of prostate might be the main causes for altered bowel habits in chronic prostatitis. Altered bowel habits should be considered as a common symptom and cure standard for chronic prostatitis.