Biochemical Characterization of Anopheles gambiae SRPN6, a Malaria Parasite Invasion Marker in Mosquitoes

Serine proteinase inhibitors of the serpin family are well known as negative regulators of hemostasis, thrombolysis and innate immune responses. Additionally, non-inhibitory serpins serve functions as chaperones, hormone transporters, or anti-angiogenic factors. In the African malaria mosquito, Anopheles gambiae s.s., at least three serpins (SRPNs) are implicated in the innate immune response against malaria parasites. Based on reverse genetic and cell biological analyses, AgSRPN6 limits parasite numbers and transmission and has been postulated to control melanization and complement function in mosquitoes. This study aimed to characterize AgSRPN6 biophysically and determine its biochemical mode of action. The structure model of AgSRPN6, as predicted by I-Tasser showed the protein in the native serpin fold, with three central β-sheets, nine surrounding α-helices, and a protruding reactive center loop. This structure is in agreement with biophysical and functional data obtained from recombinant (r) AgSRPN6, produced in Escherichia coli. The physical properties of purified rAgSRPN6 were investigated by means of analytical ultracentrifugation, circular dichroism, and differential scanning calorimetry tools. The recombinant protein exists predominantly as a monomer in solution, is composed of a mixture of α-helices and β-sheets, and has a mid-point unfolding temperature of 56°C. Recombinant AgSRPN6 strongly inhibited porcine pancreatic kallikrein and to a lesser extent bovine pancreatic trypsin in vitro. Furthermore, rAgSRPN6 formed inhibitory, SDS-stable, higher molecular weight complexes with prophenoloxidase-activating proteinase (PAP)1, PAP3, and Hemolymph protein (HP)6, which are required for melanization in the lepidopteran model organism, Manduca sexta. Taken together, our results strongly suggest that AgSRPN6 takes on a native serpin fold and is an inhibitor of trypsin-like serine proteinases.This work was supported by the National Institutes of Health through 3P20RR017708-07S1 and P20RR017686 sub-awards and 1R01AI095842 to K.M. This is contribution 12-098-J from the Kansas Agricultural Experiment Station

Design of 11-Residue Peptides with Unusual Biophysical Properties: Induced Secondary Structure in the Absence of Water

AbstractA series of oligopeptides with β-forming and adhesive properties, were synthesized and analyzed for adhesion shear strength, secondary structure, and association properties. The sequences contained related hydrophobic core segments varying in length from 5 to 12 residues and flanked by di- or tri-lysine segments. Three remarkable peptides consisting of just 11 residues with hydrophobic core sequences of FLIVI, IGSII, and IVIGS flanked by three lysine residues gave the highest dry adhesion shear strength and displayed unusual biophysical properties in the presence and absence of water. KKKFLIVIKKK had its highest adhesion strength at 2% (w/v) at pH 12.0 and showed the highest adhesion strength after exposure to water (water resistance). Both KKKIGSIIKKK and KKKIVIGSKKK, at 4% (w/v) at pH 12.0, displayed nearly identical dry shear strength values to that with the FLIVI core sequence. The peptide with IGSII core, however, displayed a lower water resistance and the latter, IVIGS, showed no water resistance, completely delaminating upon soaking in water. These are the smallest peptides with adhesive properties reported to date and show remarkable adhesion strength even at lower concentrations of 0.2% (w/v), which corresponds to 1.6mM. The FLIVI containing peptide adopted a β-sheet secondary structure in water while the IGSII- and IVIGS-containing sequences folded similarly only in the absence of water. Analytical ultracentrifugation studies showed that when the FLIVI sequence adopts β-structure in aqueous solution, it associates into a large molecular weight assembly. The random coils of IGSII and IVIGS showed no tendency to associate at any pH

Diagnostic value of circulating microRNA-21 in chronic lung allograft dysfunction after bilateral cadaveric and living-donor lobar lung transplantation

Background: MicroRNAs (miRNAs) involved in the pathogenesis of pulmonary fibrosis have been shown to be associated with the development of chronic lung allograft dysfunction (CLAD) after lung transplantation (LT). We investigated the role of circulating miRNAs in the diagnosis of CLAD after bilateral LT, including cadaveric LT (CLT) and living-donor lobar LT (LDLLT). Methods: The subjects of this retrospective study were 37 recipients of bilateral CLT (n = 23) and LDLLT (n = 14), and they were divided into a non-CLAD group (n = 24) and a CLAD group (n = 13). The plasma miRNA levels of the two groups were compared, and correlations between their miRNAs levels and percent baseline forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and total lung capacity (TLC) values were calculated from one year before to one year after the diagnosis of CLAD. Results: The plasma levels of both miR-21 and miR-155 at the time of the diagnosis of CLAD were significantly higher in the CLAD group than in the non-CLAD group (miR-21, P = 0.0013; miR155, P = 0.042). The miR-21 levels were significantly correlated with the percent baseline FEV1, FVC, and TLC value of one year before and at the time of diagnosis of CLAD (P Conclusion: Circulating miR-21 appears to be of potential value in diagnosing CLAD after bilateral LT

The prognostic impact of sarcopenia on elderly patients undergoing pulmonary resection for non-small cell lung cancer

Purpose The number of elderly patients who undergo surgery is increasing, even though they are at a high risk due to a decreased physical strength. Furthermore, sarcopenia is generally associated with a poor prognosis in patients with non-small cell lung cancer (NSCLC). Methods This study included NSCLC patients  ≥ 65 years old who underwent pulmonary resection in our hospital between 2012 and 2015. Sarcopenia was assessed using the psoas muscle mass index based on computed tomography at the level of the third lumbar vertebra. We elucidated the impact of sarcopenia on short- and long-term outcomes after surgery. Results We enrolled 259 patients, including 179 with sarcopenia. Patients with sarcopenia before surgery tended to have postoperative complications (p = 0.0521), although they did not show a poor prognosis. In patients with sarcopenia, a multivariate analysis revealed that postoperative complications and the progression of sarcopenia 1 year after surgery were significant risk factors for a poor prognosis (p = 0.0169 and 0.00370, respectively). Conclusions The progression of sarcopenia after surgery is associated with a poor prognosis in elderly NSCLC patients with sarcopenia. A strategy to prevent postoperative progressive sarcopenia may be necessary for improving the clinical outcome of this population

Successful Bronchoscopic Treatment for Postoperative Bronchopleural Fistula Using N-butyl-2-cyanoacrylate (NBCA): Report of a Post-completion Pneumonectomy Case with a History of Induction Chemoradiotherapy Followed by Bilobectomy for Advanced Lung Cancer

Bronchopleural fistula (BPF) is a severe complication following lung resection. We present the case of a patient with a history of advanced lung cancer, who had undergone induction chemoradiotherapy followed by right middle and lower lobectomy, and who developed BPF after completion right pneumonectomy. Although we had covered the bronchial stump with an omental pedicled flap, BPF was found on postoperative day 19. We covered the fistula with n-butyl-2-cyanoacrylate (NBCA) using bronchoscopy. Although we had to repeat the NBCA treatment, we ultimately cured the patient’s BPF and no recurrence was observed up to 15.2 months after surgery

Survival and prognostic factors in patients undergoing pulmonary metastasectomy for lung metastases from retroperitoneal sarcoma

Background Soft-tissue sarcomas are rare malignancies that consist of many different histologic subtypes and arise in various locations in the body. In patients with lung metastases from retroperitoneal sarcomas, the long-term outcomes and prognostic factors are unknown. This study is a retrospective review of patients undergoing pulmonary metastasectomy for retroperitoneal sarcoma metastases at one institution, with the purpose of determining prognostic factors and clinical outcomes. Methods This is a single-center, retrospective cohort study of patients undergoing pulmonary metastasectomy for lung metastases from various sarcomas at Okayama University Hospital from January 2006 to December 2018. The Kaplan-Meier method and log-rank test were used for the analyses, and cut-off values of continuous variables were determined by a receiver operating characteristic curve analysis. Results Twenty-four patients underwent the first pulmonary metastasectomy for lung metastases from retroperitoneal sarcoma in our hospital. Leiomyosarcoma was the most common histologic subtype of retroperitoneal sarcoma (79.2%, n = 19). Median overall survival was 49.9 months, and the 3-year and 5-year survival rates after the first pulmonary metastasectomy were 62.5% and 26.4% respectively. In univariate analysis, age >= 56 years, disease-free interval = 27 mm) were associated with poor survival. Conclusion Pulmonary metastasectomy can be considered as an effective management strategy in retroperitoneal sarcoma patients with lung metastases in appropriately selected cases, just as it is for other sarcomas

An initial event in insect innate immune response: structural and biological studies of interactions between β-1,3-glucan and the N-terminal domain of β-1,3-glucan recognition protein

In response to invading microorganisms, insect β-1,3-glucan recognition protein (βGRP), a soluble receptor in the hemolymph, binds to the surfaces of bacteria and fungi and activates serine protease cascades that promote destruction of pathogens by means of melanization or expression of antimicrobial peptides. Here we report on the NMR solution structure of the N-terminal domain of βGRP (N-βGRP) from Indian meal moth (Plodia interpunctella), which is sufficient to activate the prophenoloxidase (proPO) pathway resulting in melanin formation. NMR and isothermal calorimetric titrations of N-βGRP with laminarihexaose, a glucose hexamer containing β-1,3 links, suggest a weak binding of the ligand. However, addition of laminarin, a glucose polysaccharide (~ 6 kDa) containing β-1,3 and β-1,6 links that activates the proPO pathway, to N-βGRP results in the loss of NMR cross-peaks from the backbone 15N-1H groups of the protein, suggesting the formation of a large complex. Analytical ultra centrifugation (AUC) studies of formation of N-βGRP:laminarin complex show that ligand-binding induces sel-fassociation of the protein:carbohydrate complex into a macro structure, likely containing six protein and three laminarin molecules (~ 102 kDa). The macro complex is quite stable, as it does not undergo dissociation upon dilution to sub-micromolar concentrations. The structural model thus derived from the present studies for N-βGRP:laminarin complex in solution differs from the one in which a single N-βGRP molecule has been proposed to bind to a triple helical form of laminarin on the basis of an X-ray crystallographic structure of N-βGRP:laminarihexaose complex [Kanagawa, M., Satoh, T., Ikeda, A., Adachi, Y., Ohno, N., and Yamaguchi, Y. (2011) J. Biol. Chem. 286, 29158-29165]. AUC studies and phenoloxidase activation measurements carried out with the designed mutants of N-βGRP indicate that electrostatic interactions involving Asp45, Arg54, and Asp68 between the ligand-bound protein molecules contribute in part to the stability of N-βGRP:laminarin macro complex and that a decreased stability is accompanied by a reduced activation of the proPO pathway. Increased β-1,6 branching in laminarin also results in destabilization of the macro complex. These novel findings suggest that ligand-induced self-association of βGRP:β-1,3-glucan complex may form a platform on a microbial surface for recruitment of downstream proteases, as a means of amplification of the initial signal of pathogen recognition for the activation of the proPO pathway

Formative Factors of Membranous Substances on Dorsum of Tongue, Teeth, Buccal Mucosa in Elderly Persons Requiring Nursing Care

要介護者の口腔粘膜にみられる付着物は，痰，痂皮，剥離上皮と呼ばれているが，上皮成分を主体とした付着物を剥離上皮膜と定義づけ，本研究にて，要介護高齢者の口腔内に形成された剥離上皮膜を部位別に形成要因を検討した。調査対象者は，入院中の患者のうち65 歳以上の要介護高齢者70 名であった（81.1±7.7 歳）。入院記録より年齢，疾患，常用薬，寝たきり度を調査し，意識レベル，発語の可否，介助磨きの頻度は担当看護師から聴取した。歯科医師が口腔内診査を行い，膜状物質の形成の有無，Gingival Index などを評価した。形成された膜状物質は，歯科医師がピンセットで採取した。粘膜保湿度（舌背部，舌下粘膜）は，粘膜湿潤度試験紙（キソウエット®）により10秒法で評価した。採取された膜状物質は，通法に従ってパラフィン切片を作製し，HE 染色とサイトケラチン1 による免疫染色で重層扁平上皮か否かについて確認し，重層扁平上皮由来の角質変性物が認められたものを剥離上皮膜と判断した。剥離上皮膜形成の有無を従属変数として，患者背景・口腔内の14 項目，疾患の15 項目，常用薬の32項目，合計61項目を独立変数として部位ごとで決定木分析を行った。すべての部位で剥離上皮膜の形成に最優先される要因は「摂食状況」であり，経口摂取者には，剥離上皮膜がみられなかった。第2 位は舌背部で舌背湿潤度，頰部で開口，歯面の第3 位が開口であり，口腔粘膜の乾燥を示唆する結果であった。以上，剥離上皮膜の形成要因には口腔乾燥があり，保湿の維持が剥離上皮膜の予防につながると考えられた

Peptide nanovesicles formed by the self-assembly of branched amphiphilic peptides

Citation: Gudlur S, Sukthankar P, Gao J, Avila LA, Hiromasa Y, Chen J, et al. (2012) Peptide Nanovesicles Formed by the Self-Assembly of Branched Amphiphilic Peptides. PLoS ONE 7(9): e45374. https://doi.org/10.1371/journal.pone.0045374Peptide-based packaging systems show great potential as safer drug delivery systems. They overcome problems associated with lipid-based or viral delivery systems, vis-a-vis stability, specificity, inflammation, antigenicity, and tune-ability. Here, we describe a set of 15 & 23-residue branched, amphiphilic peptides that mimic phosphoglycerides in molecular architecture. These peptides undergo supramolecular self-assembly and form solvent-filled, bilayer delimited spheres with 50–200 nm diameters as confirmed by TEM, STEM and DLS. Whereas weak hydrophobic forces drive and sustain lipid bilayer assemblies, these all-peptide structures are stabilized potentially by both hydrophobic interactions and hydrogen bonds and remain intact at low micromolar concentrations and higher temperatures. A linear peptide lacking the branch point showed no self-assembly properties. We have observed that these peptide vesicles can trap fluorescent dye molecules within their interior and are taken up by N/N 1003A rabbit lens epithelial cells grown in culture. These assemblies are thus potential drug delivery systems that can overcome some of the key limitations of the current packaging systems