Polymyxin B and polymyxin E (colistin) are presently considered the last line of defense against human infections caused by multidrug-resistant Gram-negative organisms such as carbapenemase-producer Enterobacterales, Acinetobacter baumannii, and Klebsiella pneumoniae. Yet resistance to this last-line drugs is a major public health threat and is rapidly increasing. Polymyxin S₂ (S₂) is a polymyxin B analogue previously synthesized in our institute with obviously high antibacterial activity and lower toxicity than polymyxin B and colistin. To predict the possible resistant mechanism of S₂ for wide clinical application, we experimentally induced bacterial resistant mutants and studied the preliminary resistance mechanisms. Mut-S, a resistant mutant of K. pneumoniae ATCC BAA-2146 (Kpn2146) induced by S₂, was analyzed by whole genome sequencing, transcriptomics, mass spectrometry and complementation experiment. Surprisingly, large-scale genomic inversion (LSGI) of approximately 1.1 Mbp in the chromosome caused by IS26 mediated intramolecular transposition was found in Mut-S, which led to mgrB truncation, lipid A modification and hence S₂ resistance. The resistance can be complemented by plasmid carrying intact mgrB. The same mechanism was also found in polymyxin B and colistin induced drug-resistant mutants of Kpn2146 (Mut-B and Mut-E, respectively). This is the first report of polymyxin resistance caused by IS26 intramolecular transposition mediated mgrB truncation in chromosome in K. pneumoniae. The findings broaden our scope of knowledge for polymyxin resistance and enriched our understanding of how bacteria can manage to survive in the presence of antibiotics.

A series of new monobactam sulfonates is continuously synthesized and evaluated for their antimicrobial efficacies against Gram-negative bacteria. Compound 33a (IMBZ18G) is highly effective in vitro and in vivo against clinically intractable multi-drug-resistant (MDR) Gram-negative strains, with a highly druglike nature. The checkerboard assay reveals its significant synergistic effect with β-lactamase inhibitor avibactam, and the MIC values against MDR enterobacteria were reduced up to 4-512 folds. X-ray co-crystal and chemoproteomic assays indicate that the anti-MDR bacteria effect of 33a results from the dual inhibition of the common PBP3 and some class A and C β-lactamases. Accordingly, preclinical studies of 33a alone and 33a‒avibactam combination as potential innovative candidates are actively going on, in the treatment of β-lactamase-producing MDR Gram-negative bacterial infections.

Objective:To investigate the expressions and significances of autophagy-related genes Beclin-1, LC3 and p62 in esophageal squamous cell carcinoma (ESCC).Methods:The clinical data of 112 patients with primary ESCC who underwent surgery at the 81st Group Army Hospital of Chinese PLA from January 2015 to December 2016 were retrospectively analyzed. Immunohistochemistry was used to examine the expressions of Beclin-1, p62 and LC3 proteins in 112 ESCC tissues and 31 adjacent normal esophageal mucosa tissues. Furthermore, the expressions of the above three autophagy-related markers in ESCC and the relationship between their expressions and the clinicopathological characteristics of patients were analyzed.Results:The positive expression rates of Beclin-1, LC3 and p62 in ESCC tissues were 32.14% (36/112), 37.50% (42/112) and 63.39% (71/112), The positive expression rates of Beclin-1, LC3 and p62 in adjacent normal esophageal mucosa tissues were 61.29% (19/31), 64.52% (20/31) and 32.26% (10/31), and the differences were statistically significant ( χ2 values ??were 8.715, 7.216 and 9.584, all P < 0.01). The positive expression rates of Beclin-1 and LC3 in ESCC were lower than those in adjacent normal esophageal mucosa tissues, and the positive expression rate of p62 in ESCC was higher than that in adjacentnormal esophageal mucosa tissues. In ESCC patients, the expression of Beclin-1 was related to histological grade, infiltration depth, TNM staging and lymph node metastasis (all P < 0.05); the expression of LC3 was related to infiltration depth and TNM staging (both P < 0.01); the expression of p62 was related to lymph node metastasis ( P < 0.01). In ESCC, the expression of LC3 was positively correlated with the expression of Beclin-1 ( r = 0.731, P = 0.001), and negatively correlated with the expression of p62 ( r = -0.215, P = 0.023). Conclusions:Autophagy plays a certain role in the occurrence and development of ESCC. Combined detection of autophagy-related genes Beclin-1, p62 and LC3 can assist clinical diagnosis and guide follow-up comprehensive treatment.

Purpose: MicroRNAs play key regulatory roles in the tumorigenesis of hepatitis B virus-related hepatocellular carcinoma (HBVHCC). This study aimed to explore the regulatory effects of microRNA-98-5p (miR-98-5p) on the proliferation, migration, invasion, and apoptosis of HBV-HCC cells, as well as the underlying mechanisms involving nuclear factor-κB-inducing kinase (NIK). Materials and Methods: The expressions of miR-98-5p and NIK in HBV-HCC tissues and cells, and the level of HBV DNA in HBVHCC cells were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The proliferation, migration, invasion, and apoptosis of HBV-HCC cells were analyzed by cell counting kit-8, wound healing, transwell, and flow cytometry assay, respectively. The targeting relationship between miR-98-5p and NIK was predicted by StarBase3.0 and verified by dual-luciferase reporter assay. HBV-HCC xenograft tumor model was constructed in mice to observe the tumor growth in vivo. Results: The expression of miR-98-5p was declined in HBV-HCC tissues and cells. Overexpression of miR-98-5p markedly reduced the level of HBV DNA; inhibited the proliferation, migration, and invasion; and promoted the apoptosis of HBV-HCC cells. NIK was a target of miR-98-5p. Overexpression of miR-98-5p markedly decreased the protein expression of NIK in MHCC97H-HBV cells. NIK reversed the tumor-suppressing effect of miR-98-5p on HBV-HCC cells. Furthermore, overexpression of miR-98-5p significantly inhibited the xenograft tumor growth and decreased the expression of NIK in mice. Conclusion MiR-98-5p inhibits the secretion of HBV, proliferation, migration, and invasion of HBV-HCC cells by targeting NIK.

Objectives To study the clinical characteristics,diagnosis,treatment and prognosis of cancer metastases to the thyroid gland.Methods At Tianjin Medical University Cancer Hospital,from 1980 to 2016 30 patients were identified with a metastatic malignant tumor of the thyroid gland.Results Primary tumor sites were in the esophagus (26.7％),lung (16.7％),and kidney (13.3％).The median age at discovery of thyroid metastasis was 56 years old.The time lapse ranged from 0 to 108 months.There were 18 patients with metachronous metastasis with median survival of 36 months,12 patients were with synchronous metastasis,and the median survival was 8 months (P ＜ 0.01).20 patients were treated with thyroid surgery,and of which 15 patients were given post-op radiotherapy and chemotherapy.Patients who underwent thyroid resection had a median survival of 15 months,while that was 8 months in those without thyoid surgery (P ＜ 0.01).Conclusions Metastases to the thyroid gland is a rare clinical phenomenon,the prognosis of patients is mainly related to the biological behavior of primary tumors,but surgical resection and combined treatment can increase the survival rate.

Bacteremia is a life-threating syndrome often caused by methicillin-resistant (MRSA). Thus, there is an urgent need to develop novel approaches to successfully treat this infection. Staphylococcal accessory regulator A (SarA), a global virulence regulator, plays a critical role in pathogenesis and -lactam antibiotic resistance in . Hypericin is believed to act as an antibiotic, antidepressant, antiviral and non-specific kinase inhibitor. In the current study, we investigated the impact of hypericin on -lactam antibiotics susceptibility and mechanism(s) of its activity. We demonstrated that hypericin significantly decreased the minimum inhibitory concentrations of -lactam antibiotics (.., oxacillin, cefazolin and nafcillin), biofilm formation and fibronectin binding in MRSA strain JE2. In addition, hypericin significantly reduced expression, and subsequently decreased and virulence-related regulators (.., ) and genes (.., and ) expression in the studied MRSA strain. Importantly, the synergistic effect of hypericin with -lactam antibiotic (.., oxacillin) translated into therapeutic outcome in a murine MRSA bacteremia model. These findings suggest that hypericin plays an important role in abrogation of -lactam resistance against MRSA through inhibition, and may allow us to repurpose the use of -lactam antibiotics, which are normally ineffective in the treatment of MRSA infections (.., oxacillin).

The objective of this study was to investigate the genetic basis of high level aminoglycoside resistance in Acinetobacter baumannii clinical isolates from Beijing, China. 173 A. baumannii clinical isolates from hospitals in Beijing from 2006 to 2009 were first subjected to high level aminoglycoside resistance (HLAR, MIC to gentamicin and amikacin>512 µg/mL) phenotype selection by broth microdilution method. The strains were then subjected to genetic basis analysis by PCR detection of the aminoglycoside modifying enzyme genes (aac(3)-I, aac(3)-IIc, aac(6')-Ib, aac(6')-II, aph(4)-Ia, aph(3')-I, aph(3')-IIb, aph(3')-IIIa, aph(3')-VIa, aph(2″)-Ib, aph(2″)-Ic, aph(2″)-Id, ant(2″)-Ia, ant(3″)-I and ant(4')-Ia) and the 16S rRNA methylase genes (armA, rmtB and rmtC). Correlation analysis between the presence of aminoglycoside resistance gene and HLAR phenotype were performed by SPSS. Totally 102 (58.96%) HLAR isolates were selected. The HLAR rates for year 2006, 2007, 2008 and 2009 were 52.63%, 65.22%, 51.11% and 70.83%, respectively. Five modifying enzyme genes (aac(3)-I, detection rate of 65.69%; aac(6')-Ib, detection rate of 45.10%; aph(3')-I, detection rate of 47.06%; aph(3')-IIb, detection rate of 0.98%; ant(3″)-I, detection rate of 95.10%) and one methylase gene (armA, detection rate of 98.04%) were detected in the 102 A. baumannii with aac(3)-I+aac(6')-Ib+ant(3″)-I+armA (detection rate of 25.49%), aac(3)-I+aph(3')-I+ant(3″)-I+armA (detection rate of 21.57%) and ant(3″)-I+armA (detection rate of 12.75%) being the most prevalent gene profiles. The values of chi-square tests showed correlation of armA, ant(3″)-I, aac(3)-I, aph(3')-I and aac(6')-Ib with HLAR. armA had significant correlation (contingency coefficient 0.685) and good contingency with HLAR (kappa 0.940). The high rates of HLAR may cause a serious problem for combination therapy of aminoglycoside with β-lactams against A. baumannii infections. As armA was reported to be able to cause high level aminoglycoside resistance to most of the clinical important aminoglycosides (gentamicin, amikacin, tobramycin, etc), the function of aminoglycoside modifying enzyme gene(s) in A. baumannii carrying armA deserves further investigation.

OBJECTIVETo observe the effect of rectus femoris island myocutaneous flap for repairing bedsores in III and IV phases at the femoral greater trochanter area as a result of paraplegia.

METHODSThirteen paraplegic patients who suffered bedsores in III and IV phases at the greater trochanter of femur area were hospitalized from July 2009 to June 2013. The bedsores ranged from 4.5 cm×4.0 cm to 10.0 cm× 9.0 cm in area. After debridement, the size of soft tissue defect ranged from 5.0 cm×4.5 cm to 10.5 cm×10.0 cm. Rectus femoris island myocutaneous flaps were used to repair these defects, with flap area ranging from 5.0 cm×5.0 cm to 11.0 cm×10.0 cm and muscular pedicle length ranging from 8 to 12 cm. The donor sites of muscular pedicle were closed by direct suture, while those resulted from forming myocutaneous flap were closed by the transplantation of autologous skin obtained from thigh.

RESULTSNecrosis appeared at the edge of myocutaneous flap in one patient, and it was healed after dressing change. The other 12 myocutaneous flaps survived well. Patients were followed up for 2 to 30 months, and bedsore did not recur.

CONCLUSIONSRectus femoris island myocutaneous flap, with characteristics of reasonable design, large donor area, big rotation angle, and with wear-, tear-, and pressure-resistance, is suitable for repairing bedsores at III and IV phases at the greater trochanter of femur area in paraplegic patients.

Debridement ; Femur ; surgery ; Humans ; Myocutaneous Flap ; Paraplegia ; Pressure Ulcer ; surgery ; Quadriceps Muscle ; transplantation ; Reconstructive Surgical Procedures ; methods ; Surgical Flaps ; blood supply ; Treatment Outcome

Objective To compare the effect of insulin pump continuous subcutaneous insulin (CSII) and multiple subcutaneous insulin (short-acting insulin before meals + glargine,MSII) for the short duration of type 2 diabetes mellitus (T2DM) patients.Methods Fifty-two newly diagnosed T2DM patients were randomly divided into CSII(n =29) and MSII(n =23) group.Patients in CSII group were given insulin pump continuous subcutaneous plus metformin.And patients in MSII group were given insulin by multiple subcutaneous insulin injection plus metformin.The treating periods was 2 weeks and followed up one month.Results The periods from point of insulin injection to blood glucose back to normal level in CSII group was (4.70 ±2.01) d,shorter than that in MSII group(6.90 ± 1.50) d,and the difference was significant(t =2.056,P ＜0.05).The levels of C peptide in two hours postprandial before and after treatment in CSII group were (4.24 ± 0.25) ng/L,(6.29 ± 0.56) ng/L,and (3.20 ±0.11) ng/L and (7.33 ±0.41) ng/L respectively in MSII group.The levels of C peptide in two hours postprandial after treatment were higher than that of before treatment in two groups (t =2.018,2.436 respectively,P ＜0.05),but there were no significant differences between two groups(t =0.985,P ＞ 0.05).Nineteen cases (65.5％) in CSII group were off insulin treatment in one month,and 9 cases (39.1％) in MSII group.There were significant differences in two groups(x2 =5.11,P ＜0.05).Conclusion The two treatment plans can make the improvement in terms of glucose control.However,CSII plan showed more effective than MSII.

Objective To investigate the therapeutic effects of endoscopy for palliative treatment of advanced pancreatic cancer. Methods A typical case of un-resectable advanced pancreatic cancer was reviewed, who underwent obstruction of upper gastrointestinal tract, obstructive jaundice and alimentary tract hemorrhage subsequently. The patient received multiple placement of intestinal tract stents, common bile duct stents and hemostatic treatment endoscopically. Because of the obstruction of upper gastrointestinal tract, jejunalostomy and retrograde endoscopy through the orificium fistulae were performed to place bile duct stents. Results The patient survived for 10 months with good life quality after diagnosis, obstruction of upper gastrointestinal tract, obstructive jaundice and alimentary tract hemorrhage were cured and didn't recur till death.Conclusion Therapeutic endoscopy, safe and effective, is the first choice for advanced pancreatic cancer complicated with obstruction of digestive tract (including gastrointestinal tract, bile duct and pancreatic duct).