bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dendritic cells as a producer cell of beta‐defensins
Authors: Kawasaki Takashi , Kobayashi Makiko , Herndon David N , Suzuki Fujio 
Published: June 2021

Beta‐defensins (BDs) and dendritic cells (DC) have been described as major effectors on host antimicrobial innate immunities. In the present study, the ability of DC to produce BDs was explored using DC from mice with different severities of burn injuries.FT‐burned mice (BALB/c mice with 25% TBSA flame burn, 3rd degree) and PT‐burned mice (BALB/c mice with 25% TBSA scald burn, 1 to 2nd degree) were prepared as described previously. DC were isolated from spleens of mice 3 days after burn injuries, and 1×106 cells/ml of them were cultured with LPS or SAC. Culture fluids harvested 24 hrs after cultivation were assayed for BD1 and BD3 (ELISA) and a bactericidal activity (colony‐counting, P. aeruginosa). Also, DC were tested for BD mRNAs by RT‐PCR.90% of the bacterial growth was inhibited by the culture fluids of splenic DC from PT‐burned mice, while only 30% growth inhibition was shown by the culture fluids of splenic DC from FT‐burned mice. As compared with DC from normal mice, DC from PT‐burned mice produced increased amounts of BD1 and BD3 in their culture fluids, while decreased amounts of BDs were produced by DC from FT‐burned mice. The results were reproduced in 2 different assays for BDs (ELISA and RT‐PCR).These results indicate that 1) DC from spleens of mice have an ability to produce BDs, and 2) the production of BDs by DC is influenced strongly by thermally injured stress. Since PT‐burned mice are resistant and FT‐burned mice are susceptible to P. aeruginosa infection, BDs produced by DC may play an important role on the host's antibacterial resistance. (Supported by SHC NA #8610.)
IgG1 and IgG2a/c induce IL‐10 from different FcγR on macrophages as well as DCs in Leishmania mexicana infection
Authors: Buxbaum Laurence U. , Thomas Bolaji N. 
Published: June 2021

Chronic L. mexicana disease in C57BL/6 mice requires both FcRγ and IL‐10. The initial response to infection includes anti‐leishmanial IgG1 followed by a chronic phase mixed IgG1/IgG2a/c response. FcγRIII KO and IL‐10 KO mice resolve lesions with a stronger IFN‐γ response, with parasite control by 12 weeks. We also found that bone marrow‐derived macrophages (BMMΦ) from FcγRIII KO and FcRγ KO mice have the same profound defect in IL‐10 production induced by IgG1‐opsonized amastigotes. Previous reports have shown that FcγRI and IV have higher affinity binding of IgG2a/c than other FcγR. We now show that in BMMΦ, IgG1‐opsonized parasites induce IL‐10 primarily via FcγRIII, while IL‐10 induction by IgG2a/c‐opsonized parasites is mostly via FcγRI and to a lesser extent, FcγRIII. Although FcγRIV was present on BMMΦ, blockade of this receptor did not have an effect on IL‐10 induction. Similar results were obtained for BMDCs indicating both macrophages and DCs are equally capable of secreting IL‐10 in response to parasite immune complexes. Furthermore, in vivo we found that although healing FcγRIII KO mice have no alteration in IL‐10 from T cells in the draining LN, there was a 7‐fold decrease in IL‐10 from lesions, where macrophages are abundant and T cells are rare. This supports a role for both IgG1 and IgG2a/c, and macrophages and possibly DCs in generating the suppressive IL‐10 response in the lesion during infection.Funded by VA Merit.
Murine CD1d‐restricted gamma‐delta T cells respond to cardiolipin
Authors: Dieudé Mélanie , Zajonc Dirk , Behar Samuel M. , Levine Jerrold S , Rauch Joyce 
Published: June 2021

CD1d recognizes both microbial and self‐antigens, but the nature of the endogenous lipids bound by CD1d remains poorly elucidated. Cardiolipin (CL) is a major phospholipid component of bacteria that have been shown to trigger strong CD1d‐restricted responses. CL is also present in mammalian cells, but normally hidden from the immune system because of its location in the mitochondrial inner membrane. Based on growing evidence that CD1‐restricted T cells recognize phospholipids, we hypothesized that T cells in the normal immune repertoire respond to CL. Splenocytes, or liver‐derived lymphocytes, from C57BL/6 mice were incubated with bovine heart CL or control phospholipids. Proliferation occurred exclusively with CL, in a dose‐dependent manner, and was greatest in liver‐derived cells. CL‐dependent T cell stimulation was abrogated by monoclonal anti‐CD1 antibody, but was unaffected by antibody against MHC I or II. Furthermore, CL‐dependent T cell stimulation was undetectable in cells isolated from CD1d‐deficient mice. Using flow cytometry, CL‐responsive cells were shown to express gamma‐delta T cell receptor (TCR) and to produce interferon‐gamma. These findings demonstrate that a subset of CD1d‐restricted gamma‐delta T cells responsive to CL exists in the liver of healthy mice, and suggest that these cells could play a role in T cell responses to bacteria and, potentially, to self‐CL.Supported by CIHR (JR).
Mast cells and interleukin‐6 are required for the optimal accumulation of dendritic cell subpopulations in the lymph node in response to bacterial peptidoglycan
Authors: Dawicki Wojciech , Marshall Jean S. 
Published: June 2021

Acquired immune responses are shaped by the nature and activation status of dendritic cell (DC) subpopulations in the lymph node. To better understand the process of DC accumulation in the lymph node during infection we examined the importance of several proinflammatory cytokines and mast cells, which can be a potent source of factors that promote accumulation of DC in the lymph node.The number of plasmacytoid DC (pDC), CD8+ DC and CD11b+ DC in the lymph nodes that drained the site of intradermal injection of S. aureus peptidoglycan (PGN) or saline was determined at 18h post injection. To examine the importance of tumor necrosis factor (TNF), interleukin (IL)1α/β and IL‐6 in PGN induced DC recruitment, we assayed responses in mice deficient in these mediators. TNF and IL‐1 receptor were dispensable for the accumulation of pDC, CD8+ DC and CD11b+ DC in response to PGN. IL‐6 deficient mice had significantly reduced accumulation of CD11b+ DC. Examination of responses to PGN in mast cell deficient mice and mice locally reconstituted with mast cells revealed that mast cells are essential for the optimal recruitment of CD8+ DC and pDC, but not the IL‐6 dependent CD11b+ DC subset.These data suggest that PGN activated mast cells can drive the accumulation of DC subpopulations in the lymph node and thus could play a role in modulating the ensuing acquired immune responses. This work is funded by the Canadian Institutes of Health Research.
Almonds (Amygdalus communis L.) as a possible source of prebiotic functional food
Authors: Mandalari Giuseppina , Tomaino Antonio , Faulks Richard M. , Arcoraci Teresita , Bisignano Giuseppe , Saija Antonella , Wickham Martin S. , Narbad Arjan 
Published: June 2021

A prebiotic is “a nondigestible food ingredient which beneficially affects the host by selectively stimulating the growth of one or a limited number of species of bacteria in the colon thereby improving host health”. Here we describe the potential prebiotic properties of almond seeds and skins. Finely (FG) and defatted (DG) ground almonds, raw (RS) and blanched (BS) almond skins were initially digested in a simulated model of human gastric and duodenal digestion. Post‐duodenal digests were tested for potential prebiotic properties using in vitro batch fermentation systems seeded with human colonic bacteria.A significant increase in bifidobacteria and eubacteria was observed after 24h incubation with FG, whereas no significant change in the bacterial population occurred with addition of DG. Both RS and BS produced an increase in bacteria beneficial to the human colon. A prebiotic index (PI), giving a relative indication of the prebiotic potential, was calculated to be 5.0 with FG and compares well with the value of 6.4 obtained with fructo‐oligosaccharide (FOS), an established prebiotic carbohydrate. The effect on the production of short chain fatty acids, indicators of beneficial bacterial growth, was also determined. These results indicate the presence of bioactive components within almonds that stimulate growth of beneficial intestinal bacteria.This work was funded by the Almond Board of California.
Activated Notch pathway proteins and FoxG1 are co‐expressed in Medulloblastoma: correlation with phenotype
Authors: Peters L , Mehta V , Chintagumpala M , Dauser R , Adesina A 
Published: June 2021

Notch pathway activation has been implicated in the negative regulation of neural differentiation in the developing central nervous sytem. Hes 1 and Hes 5 are downstream effectors of the Notch pathway. FoxG1 forms a transcriptional repressor complex with Hes1 and was recently reported as dysregulated in all histologic types of medulloblastoma. We examined 64 medulloblastomas by IHC for nuclear expression of activated Notch‐1, Hes1, and Hes5. Activated Notch‐1, Hes1, and Hes5 expression were detected in all histologic subtypes. Using Spearman correlation (SC) analysis, there was a positive correlation between the expression of activated Notch1 and Hes1 (SC coeff 0.36, p=0.0035) and Hes 5 (SC coeff 0.433, p<0.001). Expression of FoxG1 and Notch1 also showed a weak, but significant positive correlation (SC coeff 0.273, p=0.028).Activated Notch1 expression was higher in the anaplastic subtype (ANOVA on Ranks, Dunn's test, H=12.968, p=0.002). Co‐expression of FoxG1 and Notch pathway effectors is consistent with a putative combined role of FoxG1 and activated Notch pathway in the maintenance of an undiferentiated state in medulloblastoma. In view of the reported association of myc amplification with anaplastic progression and the known Notch‐Wnt signaling pathway crosstalk, the significance of our demonstration of a correlation between Notch1 expression and the anaplastic phenotype remains to be explored.
Olmesartan reduces oxidative stress in the brains of stroke‐prone spontaneously hypertensive rats as measured by an in vivo ESR method
Authors: Araki Shuichiro , Hirooka Yoshitaka , Koga Yasuaki , Ito Koji , Kishi Takuya , Yasukawa Keiji , Utsumi Hideo , Sunagawa Kenji 
Published: June 2021

Background : We previously demonstrated that oxidative stress is involved in the neural mechanisms of hypertension. In the present study, we evaluated the effects of anti‐hypertensive treatment with the angiotensin type 1 receptor blocker olmesartan on oxidative stress in the brains of stroke‐prone spontaneously hypertensive rats (SHRSP) using the in vivo electron spin resonance (ESR)/spin probe technique. Methods and Results : Two groups of 12‐week‐old SHRSP were treated with either olmesartan (10 mg/kg/day) or hydralazine (Hyd, 20 mg/kg/day)/hydrochlorothiazide (HCT, 4.5 mg/kg/day) for 30 days (n=5 for each). Systolic blood pressure decreased after each treatment (151±8 mm Hg [olmesartan] and 156±13 mm Hg [Hyd/HCT], NS). In rats treated with Hyd/HCT, but not those treated with olmesartan, heart rate and urinary norepinephrine excretion increased. The in vivo ESR signal decay rates of the blood‐brain barrier‐permeable spin probe, methoxycarbonyl‐PROXYL, were significantly higher in SHRSP brains compared with age‐matched normotensive Wistar‐Kyoto rat brains (0.121±0.010 vs 0.098±0.011/min, P < 0.01, n=6 for each). Olmesartan attenuated the ESR signal decay rates in SHRSP brains, but Hyd/HCT did not. Conclusions : These results suggest that olmesartan has an anti‐oxidative effect in SHRSP brains, as measured by an in vivo ESR method, in addition to its blood pressure‐lowering effects.
Peripheral Insulin Resistance Accounts for Endothelial Dysfunction in Obesity
Authors: Ali Mohammed Irfan , Marrero Mario B. , Stepp David W. 
Published: June 2021

Obesity, peripheral insulin resistance (IR) and endothelial dysfunction (ED) often clinically co‐present, yet mechanistic links remain elusive. Our study tested the hypothesis that peripheral IR is the risk factor underlying ED in obesity. Using cross‐breeding we generated obese, insulin sensitive mice (KdbKPTP) from Leptin receptor mutant (KdbHPTP) mice with IR and mice lacking Protein Tyrosine Phosphatase 1B (PTP1B), a negative modulator of insulin signaling causing IR in muscle and fat (HdbKPTP). Lean mice (HdbHPTP) served as controls. Small mesenteric arteries (SMA, <150 μ m) were analyzed in vitro. Acetylcholine [ACh; +/− L‐NAME, superoxide (SO) dismutase (D)] and Nitroprusside (SNP) reactivity was used to assess endothelium‐dependent/independent dilation. Nitric Oxide (NO) independent dilation was assessed with Papaverine (PV). Maximal dilation to ACh and SNP was less in KdbHPTP than HdbHPTP (50±4, 68±8 vs 70±3, 94±2%, p<0.01) indicating ED and reduced smooth muscle (SM) NO sensitivity in KdbHPTP. SOD improved KdbHPTP dilation to ACh, suggesting a mechanistic role for SO in KdbHPTP ED. HdbKPTP had similar ACh and SNP responses to HdbHPTP. KdbKPTP had less ED versus KdbHPTP (ACh, SNP; 64±4, 94±3 vs 50±4, 68±8%, p<0.01). PV dilation was similar in all mice, ruling out non‐NO dilation as a reason for KdbHPTP ED. We conclude peripheral IR accounts for ED and decreased SM NO sensitivity in obesity. NIH HL76533
Quantitative Measurement of Endothelial Nitric Oxide Synthase in Rat Brain Tissue Homogenates Using an Enzyme‐Linked Immunosorbent Assay Kit
Authors: Czambel R. Kenneth , Kharlamov Alexander , Jones Stephen C. 
Published: June 2021

A reliable method of endothelial nitric oxide synthase (eNOS) protein measurement in brain tissue samples would enable the direct study of its regulation and expression. Current eNOS ELISA methods are designed for cell lysates (Aberle et al, Nitric Oxide, 1997, 1: 226). We investigated a commercially available human eNOS ELISA kit (R&D Systems, Minneapolis, MN) for use with rat brain tissue homogenates.Brain tissue homogenate samples from three normal male Sprague‐Dawley rats were tested for dilutional linearity and spike‐and‐recovery characteristics. Assayed in quadruplicate, a measurable amount of endogenous eNOS was detected in all unadulterated samples (40.0±1.6, 28.2±0.9, and 50.0±1.9 pg/mg wet tissue). All samples were fractionally diluted 9/10, 4/5, 7/10, 3/5, 1/2, and 2/5, with the kit calibrator diluent and displayed good dilutional linearity (linear regression correlation coefficients of 1.0, 0.97, and 0.98). Low spike‐and‐recovery rates (less than 37.5%) were obtained with neat samples; however, prediluting the sample 1/20 before spiking resulted in a 70.3% recovery suggesting eNOS detection is affected by matrix differences between the kit standard and these samples.With the addition of a correction of recovery, these results suggest the potential usage of this eNOS ELISA kit with rat brain tissue samples.Support: Pennsylvania Department of Health (Tobacco Settlement Fund)
Protective role of calreticulin in HFE hemochromatosis
Authors: Pinto Jorge P , Ramos Pedro , de Almeida Sérgio , Oliveira Susana , Breda Laura , Michalak Marek , Porto Graça , Rivella Stefano , de Sousa Maria 
Published: June 2021

Background/Aims: HFE mutations are associated with over 80% of cases of Hereditary Hemochromatosis (HH), an iron‐overload disease in which the liver is the most frequently affected organ. Research on HFE has traditionally focused on its interaction with the transferrin receptor. Recent studies suggested a more complex function for this non‐classical MHC‐I protein. The aim of this study was to examine how HFE and its two most common mutations affect the expression of selected genes in a hepatocyte‐like cell line.Methods: Gene expression was analyzed in HepG2 cells over‐expressing wild‐type and mutant HFE. The effect of HFE in iron import and oxidative stress levels was assessed. Unfolded protein response (UPR)‐activated gene expression was analyzed in peripheral blood mononuclear cells from HH patients.Results: C282Y‐HFE down‐regulated hepcidin and enhanced calreticulin mRNA expression. Calreticulin levels correlated with intracellular iron increase and were associated with protection from oxidative stress. In C282Y+/+ patients calreticulin mRNA levels correlated with the expression of the UPR marker BiP and showed a negative association with the number of HH clinical manifestations.Conclusions: The data show that expression of C282Y‐HFE triggers a stress‐protective response and suggest a role for calreticulin as a modifier of the clinical expression of HH.
Carbon dioxide movement from residual volume (RV) toward expiratory reserve volume (ERV)
Authors: Rueda Luis Antonio , Cruz Julio Cesar , Caucha Luis Jhony 
Published: June 2021

The expired CO2 reflects the dilution of alveolar CO2 present in the ERV as shown by Cruz (FASEB J. 21:609.4, 2007). Three young male subjects consented to these experiments. The breath was held at the end of a normal expiration and exhaled to RV at the end of apnea. The mass of CO2 in the ERV was computed and plotted as a function of time of apnea (time of expiration plus time of apnea). The figure belongs to one subject and shows that CO2 movement from RV to ERV increases during the first 25s and then plateaus. The ERV=2.2L decreases with time of apnea 13mL per second (F<0.05). It is concluded that 30mL of CO2 moves from RV to ERV in 25s and stops thereafter.Supported in part by ONG‐Centro de Enseñanza, Investigación y Servicios.
Ion transport properties of small airways
Authors: Shamsuddin A K M , Quinton Paul M 
Published: June 2021

The ion transport properties of small airways have been neglected because intact bronchiolar epithelia are small and extremely difficult to obtain without trauma. To accommodate the small size of the tissue, we designed a special micro‐Ussing chamber (Area=1mm2). Constant current pulses (0.5–1.0 μA) were passed across pig airway tissue and basic electrophysiolgical properties were determined. In bilateral 150 mM NaCl Ringers Vt was −1.1±0.2 mV and Rt was 89.4±9.7 Ω‐cm2. When gluconate replaced luminal chloride, Vt (−33.6±2.7 mV) and Rt (239.0±37.8 Ω‐cm2) increased significantly. Adding Fsk plus IBMX further hyperpolarized Vt (−43.0±2.1 mV) and decreased Rt (229.1±33.7 Ω‐cm2). Anion selectivity sequences are grossly the same as for CFTR. The 2:1 NaCl dilution potentials indicate that Cl− is significantly more permeable than Na+. Cl− conductances were inhibited by CFTR inhibitors. Luminal amiloride depolarized Vt and significantly increased Rt. GNa was not affected by Fsk. Bi‐ionic diffusion potentials for NMDG vs. Na+ indicate a slightly Na+ selective paracellular shunt. Small airways are highly conductive due to a major constitutively active Cl− conductance, probably CFTR. These results give the first measurements of transepithelial properties of isolated native small airways <1.5 mm (i.d.).Support: The Nancy Olmsted Trust and NIH (RO1‐HL084042).
A new approach to identification of nuclear proteins associated with chromosomal location of interest
Authors: Zhang Huiping , Wang Yuexi , Quinones Gerri , Ligon Lee A , McGown Linda B 
Published: June 2021

Chromatin immunoprecipitation (ChIP) is an important tool for testing whether proteins bind to a particular region on chromatin. We have developed a new method to determine proteins associated with a specific DNA sequence in living cells. Rather than targeting a known protein to determine its chromosomal location using ChIP, a particular chromosomal location of interest is targeted with oligonucleotide probes in order to recover the entire complement of proteins associated with that location. Either chromatin antisense rehybridization (CAR) or chromatin sense rehybridization (CSR) can be used to discover new protein interactions on chromatin.To demonstrate feasibility of this new approach to analysis of proteins in chromatin, the insulin‐linked polymorphic region (ILPR) located upstream of the human insulin gene was probed using both CAR and CSR techniques. Enzyme‐linked immunosorbent assays or mass spectrometry were then performed to determine what proteins were associated with the ILPR. Insulin and insulin‐like growth factor II, which have been shown to bind to G‐quadruplex structures formed in ILPR in vitro, were detected using CAR and CSR in the ILPR region in live cells. These newly developed CAR and CSR assays are important additions to the chromatin analysis toolbox for identification of DNA‐binding proteins without the need for prior selection of protein targets.
Directly Cardioprotective Effects of Angiotensin Converting Enzyme (ACE) Inhibitor
Authors: Aizaki Yoshimi , Yoshikawa Ayumu , Maruyama Kei , Muramatus Toshihiro , Nishimura Shigeyumi , Senbonmatsu Takaaki 
Published: June 2021

ACE or chymase plays a pivotal role in the conversion from Ang I to Ang II in renin‐angiotensin system. ACE inhibitor (ACEI) prevents Ang II through ACE not chymase, but has pleiotropic effects for cardiovascular protection resulting in great benefits for cardiovascular patients. However, how much participation of pleiotropic effects of ACEI to engage with the cardioprotective effects is controversial.Method and results: SD rats treated with Ang II (200ng/kg/min, 40days) by the osmotic pump plus 1%NaCl in drinking water, or Ang II and imidapril (40mg/kg/day in 1%NaCl drinking water, Mitsubishi Tanabe Pharma CO., LTD) showed significantly higher blood pressure and cardiac hypertrophy than those of sham operated rats. There were no significant differences between both groups. By contrast, SD rats treated with Ang II and imidapril showed normal cardiac function despite cardiac hypertrophy, and these cardiac function was significantly higher than those of SD‐rats treated with Ang II alone.Conclusion: Imidapril may prevent development of pathologically cardiac hypertrophy without reduction of blood pressure. This effect may be independent of inhibition of Ang II.
Design Novel Selective Inhibitors of Class II Fructose‐1,6‐bisphosphate Aldolase
Authors: Wang Liangchen , Labbé Geneviève , Krismanich Anthony , Dmitrienko Gary I. , Guillemette J. Guy 
Published: June 2021

Fructose‐1,6‐bisphosphate (FBP) aldolase (E.C. ) catalyzes the reversible aldol condensation of dihydroxyacetonephosphate (DHAP) and glyceraldehyde‐3‐phosphate in glycolysis, gluconeogenesis and Calvin cycle. FBP aldolases are categorized into two groups based on different catalytic mechanisms: Class I aldolases form a Schiff‐base intermediate with the substrate through an active site lysine residue, whereas Class II aldolases contain a divalent metal which coordinates and stabilizes the carbanion intermediate. Noticeably, Class II aldolase does not exist in animals or plants, making this enzyme a potential drug target for pathogenic microbial organisms such as Mycobacterium tuberculosis, Magnaporthe grisea, Pseudomonas aeruginosa and Bacillus anthracis. Our research group has found that a commercially available antidote for heavy metal poisoning is a good competitive inhibitor of Class II FBP aldolase. In order to improve the binding affinity of this inhibitor for the enzyme activate site, new molecules based upon this compound were designed, synthesized and tested against recombinant Class II FBP aldolases from aforementioned microorganisms using kinetic assays developed by our group.This research is supported by NSERC (J.G.G. and G.I.D.)