[Effect of modified double negative-pressure wound therapy combined with debridement and tension-reduced suture in treatment of patients with stage 4 pressure sores and infection in sacrococcygeal region and its surrounding area].

Objective: To investigate the effect of modified double negative-pressure wound therapy combined with debridement and tension-reduced suture in treatment of stage 4 pressure sores and infection in sacrococcygeal region and its surrounding area. Methods: From January 2015 to June 2019, 20 patients with stage 4 pressure sores and infection in sacrococcygeal region and its surrounding area were admitted to Department of Burns and Plastic Surgery and Cosmetology of Linyi People's Hospital. Among them, there were 11 males and 9 females, aged 48 to 88 years. The wounds of 13 patients were located in the sacrococcygeal region, and 8 of them had exposed sacrococcyx. The wounds of 4 patients were located in the greater trochanter area of femur, and the wounds of 3 patients were located in the ischial tuberosity area. All the patients had fever in different degree, bacterial infection, hypoproteinemia, and electrolyte imbalance, etc. at admission. After thorough debridement and dressing change, routine negative-pressure wound therapy with negative pressure value of -16.6 kPa was performed according to the scope of lesions in period Ⅰ. When granulation tissue was fresh with less exudate and without residual necrotic tissue, modified double negative-pressure wound therapy in combination with debridement and tension-reduced suture was performed immediately in period Ⅱ. Modified double negative-pressure wound therapy were persistently performed through negative pressure drainage tube inserted into deep part of wounds and negative pressure drainage tube on surface at the same time, with superficial negative pressure value of -19.9 kPa. Meanwhile, systemic anti-infection and nutritional supports were given. The wounds were monitored for the grade of wound healing and whether skin necrosis, split, or fluid accumulation develop at the suture site. The patients were followed up for 1 to 6 months after discharge to monitor wound healing. Length of hospital stay, infection condition before and after the debridement and tension-reduced suture, and complications during treatment were recorded. Results: All wounds achieved first grade healing, with the skin at the suture site healed without split, fluid accumulation, or necrosis. The patients were followed up for 1 to 6 months after discharge, with good shape of surgical incision, little pigmentation on the skin, no hypertrophic scar or contracture, and no recurrence of pressure sores. Length of hospital stay of patients was 24 to 33 d, with an average of 28.5 d. Before debridement and tension-reduced suture, 2 cases were infected with Pseudomonas aeruginosa, 1 case was infected with Escherichia coli and Staphylococcus aureus, and 1 case was infected with Proteus mirabilis. The results of bacterial culture were all negative after debridement and tension-reduced suture. During the treatment, all patients were not complicated with bone or joint infection, necrotizing fasciitis, septicemia, etc. Conclusions: Modified double negative-pressure wound therapy combined with debridement and tension-reduced suture for treatment of patients with stage 4 pressure sores and infection in sacrococcygeal region and its surrounding area is easy to operate with minimal injury, easy for patients to accept with a very high level of satisfaction, and is suitable to popularize and applicate for primary hospitals.

Polybrominated diphenyl ethers affect the reproduction and development, and alter the sex ratio of zebrafish (Danio rerio).

Polybrominated diphenyl ethers (PBDEs) have been commonly used as flame retardants and now become ubiquitous in the global environment. Using zebrafish as a model, we tested the hypothesis that PBDEs may affect the reproduction and development of fish. Zebrafish were exposed to environmentally relevant concentrations of DE-71 (a congener of PBDE commonly found in the environment) throughout their whole life cycle, and the effects of DE-71 on gonadal development, gamete quality, fertilization success, hatching success, embryonic development and sex ratio were investigated. Despite gonadal development was enhanced, reductions in spawning, fertilization success, hatching success and larval survival rate were evident, while significant increases in malformation and percentage of male were also observed in the F1 generation. Our laboratory results suggest that PBDEs may pose a risk to reproductive success and alter the sex ratio of fish in environments highly contaminated with PBDEs.

A whole life cycle assessment on effects of waterborne PBDEs on gene expression profile along the brain-pituitary-gonad axis and in the liver of zebrafish.

Polybrominated diphenyl ethers (PBDEs) are now found ubiquitously in the aquatic environment and biota, and there is a growing concern that PBDEs may disrupt endocrine systems, leading to reproductive impairments of aquatic animals. In our study, zebrafish (Danio rerio) were exposed to the 5 ng/L, 1 µg/L and 50 µg/L of DE-71 for the duration of the whole life cycle (120 days, from eggs to adults). The expression of selected genes along the brain-pituitary-gonadal (BPG) axis and liver, and the levels of plasma sex hormones were examined. In male fish, up-regulation of GnRH in brain, FSHß and LHß in pituitary, FSH-receptor, LH-receptor, and CYP19a in testis was clearly evident, while down-regulation of CYP11a and 3ß-HSD was found in testis. In female fish, a 2.4-fold up-regulation of 3ß-HSD was found in ovary upon exposure to 50 µg/L of DE-71. GnRH in brain, FSHß and LHß in pituitary were also up-regulated, while ERß, TH and TPH in brain and GnRH-receptor in pituitary were significantly down-regulated. Hepatic ERα, AR and VTG in males were all down-regulated, while hepatic ERα and AR in female were up-regulated. Serum estradiol (E2) was reduced in both male and female upon exposure to DE-71, while significant increases in serum testosterone (T) and 11-keto-testosterone (11-KT) were only found in male but not female fish. The ratio of T/E2 as well as the ratio of 11-KT/E2 in male fish increased in a dose-dependent manner upon exposure to DE-71. Our overall results showed that whole life exposure of DE-71 altered the expression of regulatory genes and receptors at all three levels of the BPG axis in zebrafish, and the responses are sex dependent. The observed disruption of GnRH and GtHs can be further related to the subsequent disruption in both levels and balance sex steroid hormones.

Confined three-dimensional plasmon modes inside a ring-shaped nanocavity on a silver film imaged by cathodoluminescence microscopy.

The confined modes of surface plasmon polaritons in boxing ring-shaped nanocavities have been investigated and imaged by using cathodoluminescence spectroscopy. The mode of the out-of-plane field components of surface plasmon polaritons dominates the experimental mode patterns, indicating that the electron beam locally excites the out-of-plane field component of surface plasmon polaritons. Quality factors can be directly acquired from the spectra induced by the ultrasmooth surface of the cavity and the high reflectivity of the silver (Ag) reflectors. Because of its three-dimensional confined characteristics and the omnidirectional reflectors, the nanocavity exhibits a small modal volume, small total volume, rich resonant modes, and flexibility in mode control.

Message-passing-interface-based parallel FDTD investigation on the EM scattering from a 1-D rough sea surface using uniaxial perfectly matched layer absorbing boundary.

A message-passing-interface (MPI)-based parallel finite-difference time-domain (FDTD) algorithm for the electromagnetic scattering from a 1-D randomly rough sea surface is presented. The uniaxial perfectly matched layer (UPML) medium is adopted for truncation of FDTD lattices, in which the finite-difference equations can be used for the total computation domain by properly choosing the uniaxial parameters. This makes the parallel FDTD algorithm easier to implement. The parallel performance with different processors is illustrated for one sea surface realization, and the computation time of the parallel FDTD algorithm is dramatically reduced compared to a single-process implementation. Finally, some numerical results are shown, including the backscattering characteristics of sea surface for different polarization and the bistatic scattering from a sea surface with large incident angle and large wind speed.

Cloning and characterization of temperature-related gene TRS1.

To investigate the mechanism of spermatogenesis arrest derived from heat treatment and to screen temperature-related genes involved in spermatogenesis, the authors analyzed the differences in gene expression between cryptorchid and scrotal testes in rats, and cloned a full-length cDNA named TRS1. In situ hybridization showed that TRS1 mRNA was mainly expressed in spermatocyte and round spermatids in testis. The expression level decreased in cryptorchid testis, suggesting that the lower scrotal temperature is a key factor in keeping the normal expression of TRS1. At the N-terminal of TRS1, there was a plecstrin homology (PH) domain signature. This PH domain has high similarity to that in PEPP2, a homosapien protein, which has a characteristic of binding phosphatidylinositol 3-phosphate via its PH domain in vitro. These findings suggest that TRS1 may be important in spermatogenesis and give clues for further research on the function of TRS1.

Mifepristone regulates expression of apoptosis related genes Fas and FasL in mouse endometrium.

AIM: To investigate the anti-implantation mechanism of mifepriston. METHODS: In situ hybridization and immunohistochemistry were applied to determine mRNA and protein. RESULTS: After mifepriston injection, the number of implantation sites were obviously reduced, mifepriston could inhibit the embryo implantation in mouse. The expression of apoptosis related genes, Fas and FasL, in mouse endometrium was also decreased after mifepriston treatment. CONCLUSION: The expression of apoptosis related genes Fas and FasL is regulated by mifepriston and the inhibitory effect of mifepriston on the embryo implantation may be mediated by action on the Fas/FasL system.

Expression of Hsp70-2 in unilateral cryptorchid testis of rhesus monkey during germ cell apoptosis.

We investigated the possible role of Hsp70-2 in germ cell apoptosis induced by heat stress in monkey unilateral cryptorchid testis. The study focused on in situ analysis of the testicular cell DNA fragmentation and on the possible relationship between Hsp70-2 expression and germ cell apoptosis. The TUNEL result showed that most of the germ cells were labeled in the cryptorchid testis on d 5 after induction of cryptorchidism; that with most of the apoptotic germ cells depleted, only a few germ cells were labeled on d 10; and that almost no apoptotic signal was observed in the cryptorchid testis on d 15 and thereafter. This indicates that the increasing germ cell degeneration in cryptorchid testis may take the form of apoptosis. Using in situ hybridization, immunohistochemistry, and Northern blot, we examined the changes of Hsp70-2 expression in the monkey cryptorchid testis. The level of Hsp70-2 mRNA decreased slightly, while the expression of HSP70-2 protein was almost unchanged at the early stage of germ cell apoptosis in the cryptorchid testis on d 5 and dropped dramatically along with the loss of apoptotic germ cells in the cryptorchid testis on d 10 after operation. It is therefore suggested that Hsp70-2 might not take part in inhibiting the apoptosis of germ cells at the early stage during operation-induced cryptorchid testis, and that Hsp70-2 gene does not belong to the immediate early related gene responsible for germ cell apoptosis induced by heat stress.

The role of protein kinases A and C pathways in the regulation of mitogen-activated protein kinase activation in response to gonadotropin-releasing hormone receptor activation.

There is convincing evidence that mitogen-activated protein kinase (MAPK) activation is coupled to both receptor tyrosine kinase and G protein-coupled receptors. The presence of the epidermal growth factor (EGF) receptor and the GnRH receptor on the surface of GGH(3)1' cells makes this cell line a good model for the assessment of MAPK activation by receptor tyrosine kinases and G protein-coupled receptors. In this study, to assess the activated and total (i.e. activated plus inactivated) MAPK, the phosphorylation state of p44 and p42 MAPKs was examined using antisera that distinguish phospho-p44/42 MAPK (Thr202/Tyr204) from p44/42 MAPK (phosphorylation state independent). The data show that both EGF (200 ng/ml) and Buserelin (a GnRH agonist; 10 ng/ml) provoke rapid activation of MAPK (within 5 and 15 min, respectively) after binding to their receptors. The role of protein kinase A (PKA) and protein kinase C (PKC) signal transduction pathways in mediating MAPK activation was also assessed. Both phorbol ester (phorbol 12-myristate 13-acetate; 10 ng/ml) and (Bu)2cAMP (1 mM) trigger the phosphorylation of MAPK, suggesting potential roles for PKC and PKA signaling events in MAPK activation in GGH(3)1' cells. Treatment of PKC-depleted cells with Buserelin activated MAPK, suggesting involvement of PKC-independent signal transduction pathways in MAPK activation in response to GnRH. Similarly, treatment of PKC-depleted cells with forskolin (50 microM) or cholera toxin (100 ng/ml) stimulated MAPK activation, whereas pertussis toxin (100 ng/ml) had no measurable effect. To further assess the role of PKA in response to EGF and Buserelin, cells were treated with EGF (200 ng/ml) for 3 min or with Buserelin (10 ng/ml) for 10 min after pretreatment with 3-isobutyl-1-methylxanthine (0.5 mM), forskolin (50 microM), or (Bu)2cAMP (1 mM) for 15 min. The results show that MAPK can be activated in a PKA-dependent manner in GGH(3)1' cells. Consistent with previous reports, the current data support the view that MAPK activation can be achieved via both PKC- and PKA-dependent signaling pathways triggered by the GnRH receptor that couples to G(q/11) and Gs alpha-subunit proteins. In contrast, G(i/o)alpha does not appear to participate in MAPK activation in GGH(3)1' cells.

[GnRH receptor and the regulation of its gene expression].

The function of GnRH(gonadotropin-releasing hormone, LHRH) is mediated by GnRH receptor (GnRHR). The study on GnRHR is one of the highlights in neuroendocrinology and reproductive biology. The latest study of GnRHR, including molecular structure of GnRHR, regulation of GnRHR gene expression, distribution of GnRHR, the regulation of GnRHR by peptide and steroid hormone, as well as signal transduction mediated by GnRHR, are reviewed in the present article. Studies on GnRHR will make great contribution to the understanding of the regulation of reproduction and its action for therapy of malignant tumor.

Synthesis and biological activity of bile acid-derived HMG-CoA reductase inhibitors. The role of 21-methyl in recognition of HMG-CoA reductase and the ileal bile acid transport system.

To increase hepatoselectivity of HMG-CoA reductase inhibitors by using the specific bile acid transport systems, deoxycholic acid-derived inhibitors 9 and 11 have been synthesized, on the basis of the concept of combining in one molecule structural requirements for specific inhibition of the HMG-CoA reductase and specific recognition by the ileal bile acid transport system. The 1-methyl-3-carboxylpropyl subunit of deoxycholic acid was replaced by the 3,5-dihydroxyheptanoic acid lactone of lovastatin, and position 12-OH was esterified with 2-methylbutyric acid. Compounds 9 and 11 were evaluated for their inhibitory activity on rat liver HMG-CoA reductase, cholesterol biosynthesis in HEP G2 cells, and [3H]taurocholate uptake in rabbit brush border membrane vesicles and compared with methyl derivatives 8 and 10. The steroidal 21-CH3 group affects both activity on HMG-CoA reductase and recognition by the ileal bile acid transport system.