Feasibility of prophylactic laparoscopic appendectomy in obese patients

PURPOSE

To investigate the feasibility of prophylactic laparoscopic appendectomy in obese patients.

MATERIALS AND METHODS

A retrospective study was performed in obese patients undergoing total laparoscopic hysterectomy (TLH) along (66 patients, TLH group) or in combination (55 patients, THL+LA group) with laparoscopic appendectomy (LA) between 2007 and 2012. Operation time, intraoperative bleeding volume, postoperative exhaust time, analgesic use, and the incidence of major complications, hospital stay and cost of hospitalization were compared.

RESULTS

The operation time was longer in THL+LA group than in TLH group (p < 0.05), while the intraoperative bleeding volume, postoperative exhaust time, postoperative morbidity, the incidence of major postoperative complications, and hospitalization time were not significantly different between the two groups.

CONCLUSION

It is safe and feasible for obese patients to undergo simultaneous LA and prophylactic appendectomy, and the combined procedure does not increase the risk of infection of hysterectomy and avoids reoperation of patients due to the recurrence of appendicitis.

Kaempferol Promotes Transplant Tolerance by Sustaining CD4+FoxP3+ Regulatory T Cells in the Presence of Calcineurin Inhibitor

Calcineurin inhibitor cyclosporine is widely used as an immunosuppressant in clinic. However, mounting evidence has shown that cyclosporine hinders tolerance induction by dampening Tregs. Therefore, it is of paramount importance to overcome this pitfall. Kaempferol was reported to inhibit DC function. Here, we found that kaempferol delayed islet allograft rejection. Combination of kaempferol and low-dose, but not high-dose, of cyclosporine induced allograft tolerance in majority of recipient mice. Although kaempferol plus either dose of cyclosporine largely abrogated proliferation of graft-infiltrating T cells and their CTL activity, both proliferation and CTL activity in mice treated with kaempferol plus low-dose, but not high-dose, cyclosporine reemerged rapidly upon treatment withdrawal. Kaempferol increased CD4+FoxP3+ Tregs both in transplanted mice and in vitro, likely by suppressing DC maturation and their IL-6 expression. Reduction in Tregs by low dose of cyclosporine was reversed by kaempferol. Kaempferol-induced Tregs exhibited both allospecific and non-allospecific suppression. Administering IL-6 abrogated allograft tolerance induced by kaempferol and cyclosporine via diminishing CD4+FoxP3+ Tregs. Thus, for the first time, we demonstrated that kaempferol promotes transplant tolerance in the presence of low dose of cyclosporine, which allows for sufficient Treg generation while minimizing side effects, resulting in much-needed synergy between kaempferol and cyclosporine.

Molecular genotyping of Mycobacterium tuberculosis in Xi'an, China, using MIRU-VNTR typing

SETTING

The molecular genotyping of Mycobacterium tuberculosis is expected to lead to a better understanding of M. tuberculosis transmission in Xi'an, one of the largest cities in Western China.

OBJECTIVE

To characterize the population of M. tuberculosis strains circulating in Xi'an and to evaluate the feasibility of the mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) typing method.

DESIGN

A total of 195 M. tuberculosis clinical isolates from Xi'an were genotyped using spoligotyping and MIRU-VNTR.

RESULTS

Thirty-two different genotypes were identified by spoligotyping, with the Beijing family identified as the largest lineage (84.6%), followed by the T1 (3.08%), T2 (1.54%), H3 (1.03%) and U (1.03%) families. The Hunter-Gaston discriminatory index (HGDI) of spoligotyping is low (HGDI = 0.392). In contrast, 15-locus MIRU-VNTR shows a higher discriminatory power (HGDI = 0.998) than 12-locus MIRU-VNTR (HGDI = 0.948). By replacing the ETR C locus with the MIRU39 locus, the discriminatory power of 15-locus MIRU-VNTR is increased to 0.999.

CONCLUSIONS

The Beijing family accounts for the vast majority of M. tuberculosis isolates in Xi'an, China. The modified 15-locus MIRU-VNTR showed high HGDI and can be used as a first-line genotyping method in combination with spoligotyping in routine epidemiological investigations in Xi'an, China.

Effects of environmental parameters and irrigation on the turgor pressure of banana plants measured using the non-invasive, online monitoring leaf patch clamp pressure probe

Turgor pressure provides a sensitive indicator for irrigation scheduling. Leaf turgor pressure of Musa acuminate was measured by using the so-called leaf patch clamp pressure probe, i.e. by application of an external, magnetically generated and constantly retained clamp pressure to a leaf patch and determination of the attenuated output pressure P(p) that is highly correlated with the turgor pressure. Real-time recording of P(p) values was made using wireless telemetric transmitters, which send the data to a receiver base station where data are logged and transferred to a GPRS modem linked to an Internet server. Probes functioned over several months under field and laboratory conditions without damage to the leaf patch. Measurements showed that the magnetic-based probe could monitor very sensitively changes in turgor pressure induced by changes in microclimate (temperature, relative humidity, irradiation and wind) and irrigation. Irrigation effects could clearly be distinguished from environmental effects. Interestingly, oscillations in stomatal aperture, which occurred frequently below turgor pressures of 100 kPa towards noon at high transpiration or at high wind speed, were reflected in the P(p) values. The period of pressure oscillations was comparable with the period of oscillations in transpiration and photosynthesis. Multiple probe readings on individual leaves and/or on several leaves over the entire height of the plants further emphasised the great impact of this non-invasive turgor pressure sensor system for elucidating the dynamics of short- and long-distance water transport in higher plants.

Organization of NMDA receptors at extrasynaptic locations

NMDA receptors are found in neurons both at synapses and in extrasynaptic locations. Extrasynaptic locations are poorly characterized. Here we used preembedding immunoperoxidase and postembedding immunogold electron microscopy and fluorescence light microscopy to characterize extrasynaptic NMDA receptor locations in dissociated hippocampal neurons in vitro and in the adult and postnatal hippocampus in vivo. We found that extrasynaptic NMDA receptors on neurons in vivo and in vitro were usually concentrated at points of contact with adjacent processes, which were mainly axons, axon terminals, or glia. Many of these contacts were shown to contain adhesion factors such as cadherin and catenin. We also found associations of extrasynaptic NMDA receptors with the membrane associated guanylate kinase (MAGUKs), postsynaptic density (PSD)-95 and SAP102. Developmental differences were also observed. At postnatal day 2 in vivo, extrasynaptic NMDA receptors could often be found at sites with distinct densities whereas dense material was seen only rarely at sites of extrasynaptic NMDA receptors in the adult hippocampus in vivo. This difference probably indicates that many sites of extrasynaptic NMDA receptors in early postnatal ages represent synapse formation or possibly sites for synapse elimination. At all ages, as suggested in both in vivo and in vitro studies, extrasynaptic NMDA receptors on dendrites or the sides of spines may form complexes with other proteins, in many cases, at stable associations with adjacent cell processes. These associations may facilitate unique functions for extrasynaptic NMDA receptors.

Protective immunity induced by daily bites from irradiated mosquitoes infected with Plasmodium yoelii

Individuals in malaria endemic regions do not develop fully protective immune responses against Plasmodium liver stage infections. In high transmission areas, individuals can be exposed to more than two infective mosquito bites daily. Their exposure to Plasmodium sporozoites, therefore, is in the form of small and frequent doses. This is very different from individuals studied in controlled immunization trials where the delivery of large numbers of radiation-attenuated sporozoites in a limited number of doses can induce sterile protective immunity. Using irradiated mosquitoes infected with Plasmodium yoelii 17XNL, we tested whether daily bites from a few mosquitoes can induce a protective immune response in mice. This immunization strategy successfully induced a protective response, preventing the development of liver stages when mice were challenged with nonirradiated sporozoites. These results provide further support for the development of liver stage vaccines. They are also a call for further study into why fully protective responses against the liver stage are not seen in individuals from endemic regions.

Effects on capacitance by overexpression of membrane proteins

Functional Channelrhodopsin-2 (ChR2) overexpression of about 10(4)channels/mum(2) in the plasma membrane of HEK293 cells was studied by patch-clamp and freeze-fracture electron microscopy. Simultaneous electrorotation measurements revealed that ChR2 expression was accompanied by a marked increase of the area-specific membrane capacitance (C(m)). The C(m) increase apparently resulted partly from an enlargement of the size and/or number of microvilli. This is suggested by a relatively large C(m) of 1.15+/-0.08 microF/cm(2) in ChR2-expressing cells measured under isotonic conditions. This value was much higher than that of the control HEK293 cells (0.79+/-0.02 microF/cm(2)). However, even after complete loss of microvilli under strong hypoosmolar conditions (100 mOsm), the ChR2-expressing cells still exhibited a significantly larger C(m) (0.85+/-0.07 microF/cm(2)) as compared to non-expressing control cells (0.70+/-0.03 microF/cm(2)). Therefore, a second mechanism of capacitance increase may involve changes in the membrane permittivity and/or thickness due to the embedded ChR2 proteins.

A combined patch-clamp and electrorotation study of the voltage- and frequency-dependent membrane capacitance caused by structurally dissimilar lipophilic anions

Interactions of structurally dissimilar anionic compounds with the plasma membrane of HEK293 cells were analyzed by patch clamp and electrorotation. The combined approach provides complementary information on the lipophilicity, preferential affinity of the anions to the inner/outer membrane leaflet, adsorption depth and transmembrane mobility. The anionic species studied here included the well-known lipophilic anions dipicrylamine (DPA⁻), tetraphenylborate (TPB⁻) and [W₂(CO)₁₀(S₂CH)]⁻, the putative lipophilic anion \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\text{B}}{\left( {{\text{CF}}_{3} } \right)}^{ - }_{4} $$\end{document} and three new heterocyclic W(CO)₅ derivatives. All tested anions partitioned strongly into the cell membrane, as indicated by the capacitance increase in patch-clamped cells. The capacitance increment exhibited a bell-shaped dependence on membrane voltage. The midpoint potentials of the maximum capacitance increment were negative, indicating the exclusion of lipophilic anions from the outer membrane leaflet. The adsorption depth of the large organic anions DPA⁻, TPB⁻ and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\text{B}}{\left( {{\text{CF}}_{3} } \right)}^{ - }_{4} $$\end{document} increased and that of W(CO)₅ derivatives decreased with increasing concentration of mobile charges. In agreement with the patch-clamp data, electrorotation of cells treated with DPA⁻ and W(CO)₅ derivatives revealed a large dispersion of membrane capacitance in the kilohertz to megahertz range due to the translocation of mobile charges. In contrast, in the presence of TPB⁻ and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\text{B}}{\left( {{\text{CF}}_{3} } \right)}^{ - }_{4} $$\end{document} no mobile charges could be detected by electrorotation, despite their strong membrane adsorption. Our data suggest that the presence of oxygen atoms in the outer molecular shell is an important factor for the fast translocation ability of lipophilic anions.

441. Renin angiotensin system polymorphisms are associated with pregnancy complications

Preeclampsia (PE), small for gestational age (SGA) and preterm birth (PTB) together affect 20% of first pregnancies. Currently there is no reliable way to identify women at risk. Polymorphims in genes in the renin angiotensin system (RAS) may be associated with impaired placentation and poor maternal response to pregnancy and hence predict risk for pregnancy complications. We aimed to determine if three functional polymorphisms in RAS genes, namely, AGT M235T, ACE (I/D) and AT1R A1166C are associated with pregnancy complications. Pregnancy trios were prospectively recruited from two public hospitals in Adelaide. Pregnancies were classified into normal (n = 110), PE (n = 26), SGA (n = 47), PE+SGA (n = 12), gestational hypertension (GH, n = 17), PTB (n = 20). PE, PE +SGA and GH were also grouped together as hypertension. Parental blood and maternal blood pressure was sampled or measured at 15 weeks gestation. Cord blood was sampled after delivery. DNA was extracted from buffy coats and genotyped using high resolution melt analyses. Maternal plasma [ACE] was measured by ELISA. Data were analysed by ANOVA and Fisher's exact test. Likelihood ratios (LR) were calculated where appropriate. Maternal ACE I/D was associated with hypertension (P = 0.001, LR = 14.8) and SGA (P = 0.019, LR = 10). Paternal AT1R A1166C was associated with PTB (P = 0.01, LR = 7.4). For ACE I/D, plasma [ACE] in women with DD was 33% and 62% higher than ID and II, respectively (both P < 0.001). Systolic blood pressure in women with DD was 6% higher than II (P = 0.04). Our data suggest that RAS polymorphisms are associated with pregnancy complications. Furthermore, maternal ACE genotype determines plasma [ACE] and affects blood pressure at 15 weeks gestation, well before symptoms manifest. Our data also suggest that paternal genotype may be important in determining risk for pregnancy complications, consistent with the role of paternity in their aetiology.

Role of 2-5A-dependent RNase-L in senescence and longevity

Senescence is a permanent growth arrest that restricts the lifespan of primary cells in culture, and represents an in vitro model for aging. Senescence functions as a tumor suppressor mechanism that can be induced independent of replicative crisis by diverse stress stimuli. RNase-L mediates antiproliferative activities and functions as a tumor suppressor in prostate cancer, therefore, we examined a role for RNase-L in cellular senescence and aging. Ectopic expression of RNase-L induced a senescent morphology, a decrease in DNA synthesis, an increase in senescence-associated beta-galactosidase activity, and accelerated replicative senescence. In contrast, senescence was retarded in RNase-L-null fibroblasts compared with wild-type fibroblasts. Activation of endogenous RNase-L by 2-5A transfection induced distinct senescent and apoptotic responses in parental and Simian virus 40-transformed WI38 fibroblasts, respectively, demonstrating cell type specific differences in the antiproliferative response to RNase-L activation. Replicative senescence is a model for in vivo aging; therefore, genetic disruption of senescence effectors may impact lifespan. RNase-L-/- mice survived 31.7% (P<0.0001) longer than strain-matched RNase-L+/+ mice providing evidence for a physiological role for RNase-L in aging. These findings identify a novel role for RNase-L in senescence that may contribute to its tumor suppressive function and to the enhanced longevity of RNase-L-/- mice.