In clinical practice, skin defects resulted from various acute and chronic diseases occur frequently. Dermal substitute (DS), known as dermal regenerative template, is used more and more widely, but the slow process of vascularization limits its clinical application. At present, there are many strategies developed to enhance the process of vascularization, such as modifying the structure of dermal scaffolds, prevascularization by seeding stem cells and/or endothelial cells. Recently, negative-pressure wound therapy (NPWT) emerged and rapidly became popular in promoting wound healing due to its intrinsic advantages. Furthermore, some researchers introduced this technique to accelerate the vascularization process of DS. This paper represents a comprehensive overview on the efficiency of NPWT in different combination models, and the related mechanism.

Since its establishment for 60 years, Department of Burns of the Second Affiliated Hospital of Zhejiang University School of Medicine has grown into a famous regional burn center in China under the leading of the pioneers and through the efforts of several generations. The department has distinctive disciplinary features in burn care, nutritional support, scar prevention and treatments, standard management of chronic wound, and skin tissue engineering research, making positive contribution to the development of burn medicine in China.

BACKGROUNDMycobacterium abscessus (M. abscessus) can cause a variety of human infections, involving the lung, skin and soft tissues, and is generally believed to be acquired from environmental sources. The aim of this study was to investigate the molecular diversity and antibiotic susceptibility of M. abscessus isolates as the basis for strategies to improve control and management of infection.

METHODSSeventy M. abscessus isolates from patients attending the Guangzhou Thoracic Hospital were identified from 2003 to 2005 by biochemical tests, gas chromatography, polymerase chain reaction (PCR)-restriction analysis (PRA) of heat shock protein gene hsp65, and sequencing of the quinolone resistance determining regions (QRDRs) of gyrA. Susceptibilities to six antibiotics were determined by micro-broth dilution. Isolates were genotyped using randomly amplified polymorphic DNA (RAPD) analysis.

RESULTSMost isolates (63/70; 90%) were susceptible to amikacin but rates of susceptibility to other antibiotics varied from moderate, clarithromycin (60%) and imipenem (43%), to low for ciprofloxacin and ofloxacin (3%), and 87% of isolates had intermediate susceptibility to cefoxitin. RAPD analysis showed that the 70 clinical isolates displayed 69 unique RAPD patterns.

CONCLUSIONSThe high genetic diversity of isolates suggests that they are not transmitted from person to person but, presumably, are acquired independently from environmental sources. M. abscessus isolates displayed variable levels of susceptibility to all antibiotics tested, other than amikacin, indicating a need for routine susceptibility testing to guide treatment.

Amikacin ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Cefoxitin ; pharmacology ; China ; Chromatography, Gas ; Ciprofloxacin ; pharmacology ; Clarithromycin ; pharmacology ; Imipenem ; pharmacology ; Microbial Sensitivity Tests ; Mycobacterium ; drug effects ; genetics ; Polymerase Chain Reaction ; Random Amplified Polymorphic DNA Technique

OBJECTIVETo explore the influences of Mycobacterium tuberculosis on the levels of human acute monocytic leukemia cell line THP-1 apoptosis and death.

METHODSHuman acute monocytic leukemia cell line THP-1 were infected with Mycobacterium tuberculosis strains H37Ra, H37Rv, or Beijing genotype (BJTB), respectively, to construct the infection models. Cell apoptosis was detected using flow cytometry. The distribution of the apoptotic proteins was detected using immunofluorescent staining assays. The cells late apoptosis was detected using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining assays. The change of cell death was determined by Tyrpan blue staining assays.

RESULTSTHP-1 apoptosis was induced by Mycobacterium tuberculosis strains H37Ra, H37Rv, and BJTB. H37Ra strongly induced THP-1 apoptosis, H37Rv weakly induced THP-1 apoptosis, and BJTB induced THP-1 apoptosis at the lowest level among these three Mycobacterium tuberculosis strains. On the contrary, BJTB strongly induced THP-1 death, H37Rv weakly induced THP-1 death, and H37Ra induced THP-1 death at the lowest level.

CONCLUSIONSMycobacterial strains with different virulence induce different levels of apoptosis and death of THP-1 cells. Compared with highly virulent strains, attenuated strains induce more apoptosis and less death.

Apoptosis ; Cell Line, Tumor ; Humans ; In Situ Nick-End Labeling ; Leukemia, Monocytic, Acute ; Mycobacterium tuberculosis ; pathogenicity ; Virulence

OBJECTIVETo investigate the effects of poly-lactic-co-glycolic acid (PLGA) knitted mesh/collagen-chitosan hybrid scaffold (PCCS) on angiogenesis, and to explore the relative mechanisms.

METHODSPLGA knitted mesh was integrated into collagen-chitosan scaffold (CCS) to construct PCCS with freeze-lyophilizing method, and CCS was made with the same method. The characteristics of morphology and water absorbing capacity among PCCS, PLGA knitted mesh, and CCS were compared in vitro. PCCS and CCS was respectively implanted into subcutaneous tissue of back on both sides in 24 SD rats, and the tissue specimens were harvested at post operation week (POW) 1, 2, and 4 according to the random number table to evaluate the level of angiogenesis by histopathological and immunohistochemical examinations. The expression levels of alpha smooth muscle actin (alpha-SMA) and vascular endothelial growth factor (VEGF) mRNA were examined by real-time quantitative RT-PCR. Data were processed with t test.

RESULTS(1) PLGA knitted mesh was closely integrated with sponge of collagen-chitosan in PCCS, and the porous structure of PCCS was similar to that of CCS. (2) Compared with that of PCCS [(506 +/- 15)%], the water absorbing rate of CCS and PLGA knitted mesh was respectively increased and decreased [(627 +/- 21)%, (195 +/- 15)%, with t value respectively 3.8, 11.9, P < 0.05 or P < 0.001]. (3) The scaffolds were filled with newly formed tissue in CCS at POW 4, while those in PCCS were observed at POW 2 with more homogeneous and abundant collagen. (4) Blood vessels could be induced, and they grew into scaffolds along with prolongation of implantation time in PCCS and CCS. The number of mature blood vessels in PCCS at POW 1, 2, 4 [(10.7 +/- 3.2), (18.6 +/- 2.1), and (30.3 +/- 4.5) branches per square centimeter] was respectively higher than that in CCS [(5.4 +/- 0.9), (10.8 +/- 4.2), and (23.6 +/- 1.7) branches per square centimeter, with t value respectively 4.6, 4.4, 4.5, P values all below 0.01]. (5) The expression levels of alpha-SMA and VEGF mRNA in PCCS at POW 1, 2, 4 were significantly higher than those in the CCS (with t(alpha-SMA) value respectively 1.26, 1.63, 2.17, with t(VEGF) value respectively 5.52, 2.07, 1.78, P values all below 0.01).

CONCLUSIONSPCCS is able to induce the ingrowth of blood vessels rapidly and promote their maturity. The mechanical properties and microstructures of scaffolds play synergistic role in the process of angiogenesis.

Animals ; Biocompatible Materials ; Chitosan ; pharmacology ; Collagen ; pharmacology ; Lactic Acid ; pharmacology ; Male ; Materials Testing ; Neovascularization, Physiologic ; drug effects ; Polyglycolic Acid ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Tissue Engineering ; methods ; Tissue Scaffolds

OBJECTIVETo design and construct a kind of dermal regeneration template with mesh, and to preliminarily evaluate its biological characteristics.

METHODSPLGA mesh was integrated into CCS with freeze-drying method for constructing PLGA mesh/CCS composite (PCCS). The micromorphologies and mechanical properties among PLGA mesh, CCS, and PCCS were compared. PCCS and CCS was respectively implanted into subcutaneous tissue of SD rats (PCCS and CCS groups, 9 rats in each group). The tissue samples were collected at post operation week (POW) 1, 2, and 4 for histopathological and immunohistochemical observation. Protein levels of CD68, MPO, IL-1beta, IL-10 were examined by Western blot, with expression of gray value. Data were processed with one-way analysis of variance and t test.

RESULTSThree-dimensional porous structure of PCCS was similar to that of CCS. Mechanical property of PLGA mesh and PCCS was respectively (3.07 +/- 0.10), (3.26 +/- 0.15) MPa, and they were higher than that of CCS [(0.42 +/- 0.21) MPa, F = 592.3, P < 0.0001)]. The scaffolds were filled with newly formed tissue in PCCS group at POW 2, while those in CCS group were observed at POW 4. A large accumulation of macrophages was observed in both groups, especially at POW 2, and more macrophage infiltration was observed in CCS group. The protein level of IL-10 in PCCS group at POW 2 was obviously higher than that in CCS group, while the protein levels of CD68, MPO, IL-1beta were significantly decreased as compared with those in CCS group (with t value from -4.06 to 2.89, P < 0.05 or P < 0.01).

CONCLUSIONSPCCS has excellent mechanical property with appropriate three-dimensional porous structure. Meanwhile, it can rapidly induce formation of new tissue and vascularization, and it has a prospect of serving as a dermal substitute.

Animals ; Cells, Cultured ; Chitosan ; chemistry ; Collagen ; chemistry ; Extracellular Matrix ; chemistry ; Lactic Acid ; chemistry ; Male ; Materials Testing ; Polyglycolic Acid ; chemistry ; Prosthesis Design ; Rats ; Rats, Sprague-Dawley ; Regeneration ; Skin, Artificial ; Tissue Engineering ; methods ; Tissue Scaffolds

OBJECTIVETo clarify three-grade criteria of curative resection for primary liver cancer (PLC) and evaluate their clinical significance.

METHODSCriteria of curative resection of PLC were summed up to three grades. Grade I: complete removal of all gross tumors with no residual tumor at the excision margin. Grade II: on the basis of Grade I, there was no extrahepatic metastasis, no hilar lymph node metastasis, no tumor thrombus in the main trunks and their primary tributaries of the portal vein, common hepatic duct, hepatic vein and vena cava inferior, and the tumor was not more than two in number. Grade III: in addition to the above criteria, AFP dropped to normal level (in patients with elevated AFP before surgery) within 2 months after operation, and no residual tumor upon diagnostic imaging. A total of 354 cases with PLC who had their liver resected was reviewed. Patients in each grade were divided into two portions depending on whether the treatment was curative or palliative.

RESULTSThe survival of patients receiving curative treatment was better than those receiving palliative treatment (P < 0.01). This was true for patients whose treatment belonged to anyone of the three-grade criteria. The survival was improved along with the promotion of curative criteria used. The 5-year survival rate of Grade I, II and III patients undergone curative resection was 43.2%, 51.2% and 64.4%, respectively (P < 0.01).

CONCLUSION1. The three-grade criteria may be used for judging the radicality of tumor resection for PLC. 2. The more stringent the criteria used, the better the survival would be. 3. Adopting high-grade criteria to select cases, to guide operation and postoperative follow-up would improve the results of liver resection for PLC.

Female ; Hepatectomy ; methods ; Humans ; Liver Neoplasms ; mortality ; surgery ; Male ; Middle Aged ; Survival Rate

BACKGROUNDTo confirm if Puumala like viruses exist in China.

METHODSRNA was extracted from lungs of bank voles captured in the Northeast China, partial S segments genome of Puumala viruses were amplified and sequenced.

RESULTS926 bp cDNA of S segments of Puumala like virus was amplified and sequenced. The phylogenetic analysis revealed that the Puumala like viruses found in China were most close to that found in Far East region of Russia.

CONCLUSIONSPuumala like virus does exist in Northeast China, and the nucleotides sequence of the viruses have high homolog to Puumala viruses found in Russia.

Animals ; China ; DNA, Viral ; analysis ; Hemorrhagic Fever with Renal Syndrome ; virology ; Lung ; virology ; Mice ; Phylogeny ; Puumala virus ; isolation & purification ; Sequence Analysis, DNA ; Sequence Homology, Nucleic Acid

OBJECTIVETo evaluate the effect of postoperative adjuvant transcatheter arterial chemoembolization (TACE) on hepatocellular carcinoma (HCC) patients with residual tumor.

METHODSThe patients were classified into intervention group (with adjuvant TACE) and control group (without adjuvant TACE) who were further stratified to those with high risk (patients with single tumor > 5 cm in diameter, or with multiple tumors, invasion to blood vessels), and low risk factors. Univariate analysis and Cox model were used to analyse prognostic factors.

RESULTSIn low risk patients with residual tumor, the 1-, 2-, 3-, 4-year survival rate was 97.2%, 78.0%, 66.5% and 66.5% in the intervention group, and 91.2%, 81.4%, 70.3% and 54.4% in the control group, respectively. There was no statistical difference between the two groups in survival (log-rank P = 0.7667). Comparing with the control group, the 1-, 2-, 3-, 4-year survival rate was 89.5%, 73.4%, 59.2% and 53.8% in the intervention group, and 70.5%, 61.9%, 46.8% and 46.8% in the control group, respectively. Postoperative adjuvant TACE significantly prolonged the survival in high risk patients with residual tumor (P = 0.0029). Cox model revealed that the benefit of adjuvant TACE was significantly increased by the high risk factors in HCC patients with residual tumor.

CONCLUSIONThe beneficial effect of postoperative TACE was only observed in high risk patients with residual tumor but not in the low risk patients with residual tumor.

Adult ; Aged ; Carcinoma, Hepatocellular ; mortality ; therapy ; Chemoembolization, Therapeutic ; Combined Modality Therapy ; Female ; Hepatic Artery ; Humans ; Liver Neoplasms ; mortality ; therapy ; Male ; Middle Aged ; Neoplasm, Residual ; Survival Rate

A 59-year-old male patient with local sinus tract formation due to residual foreign body was admitted to the Second Affiliated Hospital of Zhejiang University College of Medicine on December 17, 2018. The examination showed that the residual foreign body was the component of a sticky cloth implanted when the patient underwent appendectomy 27 years ago. Hypertrophic scar developed at the right-lower abdominal incision for appendectomy 23 years ago and the secondary infection after cicatrectomy resulted in non-healing of the wound. The chronic refractory wound healed completely after surgical treatment in our hospital after this admission. The postoperative pathological examination revealed local inflammatory granuloma. This case suggests that chronic refractory wound is likely to form when secondary infection occurs following the surgical procedure near the implant, and aggressive surgery is an effective way to solve this problem.
Abdomen ; Abdominal Cavity ; Cicatrix, Hypertrophic ; Coinfection ; Foreign Bodies/surgery* ; Humans ; Male ; Middle Aged