Therapeutic Actions Oxygen Therapy

NCBI pubmed

Stroop Task-Related Brain Activity in Patients With Insomnia: Changes After Cognitive-Behavioral Therapy for Insomnia.

Stroop Task-Related Brain Activity in Patients With Insomnia: Changes After Cognitive-Behavioral Therapy for Insomnia. Behav Sleep Med. 2018 Feb 16;:1-13 Authors: Hwang JY, Kim N, Kim S, Park J, Choi JW, Kim SJ, Kang CK, Lee YJ Abstract OBJECTIVE/BACKGROUND: In the present study, we compared differences in brain activity during the Stroop task between patients with chronic insomnia disorder (CID) and good sleepers (GS). Furthermore, we evaluated changes in Stroop task-related brain activity after cognitive-behavioral therapy for insomnia (CBT-I). PARTICIPANTS/METHODS: The final analysis included 21 patients with CID and 25 GS. All participants underwent functional magnetic resonance imaging (fMRI) while performing the color-word Stroop task. CBT-I, consisting of 5 sessions, was administered to 14 patients with CID in the absence of medication. After CBT-I, fMRI was repeated in the patients with CID while performing the same task. Sleep-related questionnaires and sleep variables from a sleep diary were also obtained before and after CBT-I. RESULTS: No significant differences in behavioral performance in the Stroop task or task-related brain activation were observed between the CID and GS groups. No changes in behavioral performance or brain activity were found after CBT-I. However, clinical improvement in the Insomnia Severity Index (ISI) score was significantly associated with changes in the Stroop task-related regional blood oxygen level-dependent signals in the left supramarginal gyrus. CONCLUSIONS: Our findings suggest that cognitive impairment in patients with CID was not detectable by the Stroop task or Stroop task-related brain activation on fMRI. Moreover, there was no altered brain activity during the Stroop task after CBT-I. However, the ISI score reflected changes in the neural correlates of cognitive processes in patients with CID after CBT-I. PMID: 29451994 [PubMed - as supplied by publisher]

Influence of hyperbaric oxygen on biomechanics and structural bone matrix in type 1 diabetes mellitus rats.

Influence of hyperbaric oxygen on biomechanics and structural bone matrix in type 1 diabetes mellitus rats. PLoS One. 2018;13(2):e0191694 Authors: Limirio PHJO, da Rocha Junior HA, Morais RB, Hiraki KRN, Balbi APC, Soares PBF, Dechichi P Abstract BACKGROUND: The aim of this study was to evaluate the biomechanics and structural bone matrix in diabetic rats subjected to hyperbaric oxygen therapy (HBO). METHODS: Twenty-four male rats were divided into the following groups: Control; Control + HBO; Diabetic, and Diabetic + HBO. Diabetes was induced with streptozotocin (STZ) in the diabetic Groups. After 30 days, HBO was performed every 48h in HBO groups and all animals were euthanized 60 days after diabetic induction. The femur was submitted to a biomechanical (maximum strength, energy-to-failure and stiffness) and Attenuated Total Reflectance Fourier transform infrared (ATR-FTIR) analyses (crosslink ratio, crystallinity index, matrix-to-mineral ratio: Amide I + II/Hydroxyapatite (M:MI) and Amide III + Collagen/HA (M:MIII)). RESULTS: In biomechanical analysis, diabetic animals showed lower values of maximum strength, energy and stiffness than non-diabetic animals. However, structural strength and stiffness were increased in groups with HBO compared with non-HBO. ATR-FTIR analysis showed decreased collagen maturity in the ratio of crosslink peaks in diabetic compared with the other groups. The bone from the diabetic groups showed decreased crystallinity compared with non-diabetic groups. M:MI showed no statistical difference between groups. However, M:MIII showed an increased matrix mineral ratio in diabetic+HBO and control+HBO compared with control and diabetic groups. Correlations between mechanical and ATR-FTIR analyses showed significant positive correlation between collagen maturity and stiffness. CONCLUSIONS: Diabetes decreased collagen maturation and the mineral deposition process, thus reducing biomechanical properties. Moreover, the study showed that HBO improved crosslink maturation and increased maximum strength and stiffness in the femur of T1DM animals. PMID: 29451877 [PubMed - in process]

Organic Semiconducting Photoacoustic Nanodroplets for Laser-Activatable Ultrasound Imaging and Combinational Cancer Therapy.

Organic Semiconducting Photoacoustic Nanodroplets for Laser-Activatable Ultrasound Imaging and Combinational Cancer Therapy. ACS Nano. 2018 Feb 16;: Authors: Tang W, Yang Z, Wang S, Wang Z, Song J, Yu G, Fan W, Dai Y, Wang J, Shan L, Niu G, Fan Q, Chen X Abstract Combination of photoacoustic (PA) and ultrasound (US) imaging offers high spatial resolution images with deep tissue penetration, which shows great potentials in applications in medical imaging. Development of PA/US dual-contrast agents with high contrast and excellent biocompatible is of great interest. Herein, an organic semiconducting photoacoustic nanodroplet, PS-PDI-PAnD, is developed by stabilizing low-boiling-point perfluorocarbon (PFC) droplet with a photoabsorber and photoacoustic agent of perylene diimide (PDI) molecules and co-encapsulating the droplet with photosensitizers of ZnF16Pc molecules. Upon irradiation, the PDI acts as an efficient photoabsorber to trigger the liquid-to-gas phase transition of the PFC, resulting in dual-modal PA/US imaging contrast as well as photothermal heating. On the other hand, PFC can serve as an O2 reservoir to overcome the hypoxia-associated resistance in cancer therapies, especially in photodynamic therapy. The encapsulated photosensitizers will benefit from the sustained oxygen release from the PFC, leading to promoted photodynamic efficacy regardless of pre-existing hypoxia in the tumors. When intravenously injected into tumor-bearing mice, the PS-PDI-PAnDs show a high tumor accumulation via EPR effect. With a single 671-nm laser irradiation, the PS-PDI-PAnDs exhibit a dual-modal PA/US imaging-guided synergistic photothermal and oxygen self-enriched photodynamic treatment, resulting in complete tumor eradication and minimal side effects. The PS-PDI-PAnDs represents a type of PFC nanodroplets for synergistic PDT/PTT treatment upon a single laser irradiation, which is expected to hold great potential in the clinical translation in dual-modal PA/US imaging-guided combinational cancer therapy. PMID: 29451774 [PubMed - as supplied by publisher]

Enhanced Photodynamic Therapy by Reduced Intracellular Glutathione Levels Employing Nano-MOF with Cu (II) as Active Center.

Related Articles Enhanced Photodynamic Therapy by Reduced Intracellular Glutathione Levels Employing Nano-MOF with Cu (II) as Active Center. Angew Chem Int Ed Engl. 2018 Feb 16;: Authors: Zhang W, Lu J, Gao X, Li P, Zhang W, Ma Y, Wang H, Tang B Abstract In photodynamic therapy (PDT), the level of reactive oxygen species (ROS) produced in the cell directly determines therapeutic effect. Therefore, the development of photosensitizers combining the ability of reducing GSH levels through synergistically improving ROS concentration to strengthen the efficacy of PDT for tumor is important. We report a nano-metal-organic framework based on Cu (II) as active center for PDT. This MOF-2 is readily uptaken by breast cancer cells, and high-level ROS is generated under light irradiation. Meanwhile, intracellular GSH is considerably decreased owing to absorption on MOF-2, synergistically increasing ROS concentration and accelerating apoptosis, thereby enhancing the effect of PDT. Notably, through the direct adsorption of GSH, MOF-2 showed comparable effect with commercial antitumor drug camptothecin in mouse breast cancer treatment. This work provides strong evidence for MOF-2 as a promising new PDT candidate and anti-cancer drug. PMID: 29451722 [PubMed - as supplied by publisher]

Upconversion in photodynamic therapy: plumbing the depths.

Related Articles Upconversion in photodynamic therapy: plumbing the depths. Dalton Trans. 2018 Feb 16;: Authors: Hamblin MR Abstract Photodynamic therapy (PDT) involves the combination of non-toxic dyes called photosensitizers (PS) and harmless visible light that interact with ambient oxygen to give reactive oxygen species (ROS) that can damage biomolecules and kill cells. PDT has mostly been developed as a cancer therapy but can also be used as an antimicrobial approach against localized infections. However even the longest wavelength used for exciting PS (in the 700 nm region) has relatively poor tissue penetration, and many PS are much better excited by blue and green light. Therefore upconversion nanoparticles (UCNPs) have been investigated in order to allow deeper-penetrating near-infrared light (980 nm or 810 nm) to be used for PDT. NaYF4 nanoparticles doped with Yb3+ and Er3+ or with Tm3+ and Er3+ have been attached to PS either by covalent conjugation, or by absorption to the coating or shell (used to render the UCNPs biocompatible). Forster resonance energy transfer to the PS then allows NIR light energy to be transduced into ROS leading to cell killing and tumor regression. Some studies have experimentally demonstrated the deep tissue advantage of UCNP-PDT. Recent advances have included dye-sensitized UCNPs and UCNPs coupled to PS, and other potentially synergistic drug molecules or techniques. A variety of bioimaging modalities have also been combined with upconversion PDT. Further studies are necessary to optimize the drug-delivery abilities of the UCNPs, improve the quantum yields, allow intravenous injection and tumor targeting, and ensure lack of toxicity at the required doses before potential clinical applications. PMID: 29451568 [PubMed - as supplied by publisher]

Calciphylaxis as cutaneous marker of hyperparathyroidism and successful outcome with parathyroidectomy followed by hyperbaric oxygen therapy.

Related Articles Calciphylaxis as cutaneous marker of hyperparathyroidism and successful outcome with parathyroidectomy followed by hyperbaric oxygen therapy. Indian J Dermatol Venereol Leprol. 2018;84(2):209-211 Authors: Hemdani R, Rajput GR, Sridhar J, Chatterjee M, Rathod D PMID: 29451194 [PubMed - in process]

Reversible platypnoea-orthodeoxia syndrome in post-tuberculosis bronchial stenosis.

Related Articles Reversible platypnoea-orthodeoxia syndrome in post-tuberculosis bronchial stenosis. Respirol Case Rep. 2018 Apr;6(3):e00303 Authors: Tan GP, Abisheganaden JA, Goh SK, Verma A Abstract Bronchial stenosis is known to complicate endobronchial tuberculosis despite medical therapy. It is often associated with dyspnoea. In severe cases, bronchial stenosis results in airflow obstruction, impaired secretion clearance, and can lead to respiratory failure. We present an unusual observation of platypnoea-orthodeoxia syndrome in a young woman with acute atelectasis due to post-tuberculosis bronchial stricture. Imaging revealed complete middle and right lower lobe atelectasis with a partially aerated right upper lobe. In the sitting posture, there was positional worsening of dyspnoea associated with an increase in the alveolar-arterial oxygen gradient and shunt fraction. The likely mechanism was due to gravitational difference in ventilation-perfusion matching. The platypnoea-orthodeoxia syndrome was reversible following balloon dilatation of the bronchial stenosis and expansion of the collapsed lung. PMID: 29449947 [PubMed]

Ultrasound beam steering of oxygen nanobubbles for enhanced bladder cancer therapy.

Related Articles Ultrasound beam steering of oxygen nanobubbles for enhanced bladder cancer therapy. Sci Rep. 2018 Feb 15;8(1):3112 Authors: Bhandari P, Novikova G, Goergen CJ, Irudayaraj J Abstract New intravesical treatment approaches for bladder cancer are needed as currently approved treatments show several side effects and high tumor recurrence rate. Our study used MB49 murine urothelial carcinoma model to evaluate oxygen encapsulated cellulosic nanobubbles as a novel agent for imaging and ultrasound guided drug delivery. In this study, we show that oxygen nanobubbles (ONB) can be propelled (up to 40 mm/s) and precisely guided in vivo to the tumor by an ultrasound beam. Nanobubble velocity can be controlled by altering the power of the ultrasound Doppler beam, while nanobubble direction can be adjusted to different desired angles by altering the angle of the beam. Precise ultrasound beam steering of oxygen nanobubbles was shown to enhance the efficacy of mitomycin-C, resulting in significantly lower tumor progression rates while using a 50% lower concentration of chemotherapeutic drug. Further, dark field imaging was utilized to visualize and quantify the ONB ex vivo. ONBs were found to localize up to 500 µm inside the tumor using beam steering. These results demonstrate the potential of an oxygen nanobubble drug encapsulated system to become a promising strategy for targeted drug delivery because of its multimodal (imaging and oxygen delivery) and multifunctional (targeting and hypoxia programming) properties. PMID: 29449656 [PubMed - in process]

Restoration of sleep using a novel biomimetic protocol for adult OSA: Clinical case report.

Related Articles Restoration of sleep using a novel biomimetic protocol for adult OSA: Clinical case report. Cranio. 2018 Feb 15;:1-4 Authors: Singh GD, Kraver M, Chernyshev O Abstract Background A sleep study of a 56-year old male with excessive daytime sleepiness demonstrated an AHI of 16.4hr-1 with 13% of total sleep time in REM sleep and a mean oxygen desaturation (SpO2) of 86%. Clinical presentation On intra-oral examination, it was found that the patient had maxillary hypoplasia and bilateral torus mandibularis. A 3D cone-beam CT (CBCT) scan was taken, and 28 craniofacial parameters were measured. Surgical reduction of the mandibular tori followed by biomimetic oral appliance therapy (BOAT) was initiated. After 14 months, a post-treatment CBCT scan revealed that 70% of parameters measured had improved. Therefore, another sleep study was performed with no device in the mouth. This follow-up home sleep test demonstrated that the AHI fell to 5.3hr-1hr; with 27% REM sleep, and a mean SpO2 of 93% without any device in the mouth. Conclusion These findings suggest that BOAT might be able to restore sleep in certain adult cases. PMID: 29448905 [PubMed - as supplied by publisher]

Multifunctional mesoporous silica nanoparticles as efficient transporters of doxorubicin and chlorin e6 for chemo-photodynamic combinatorial cancer therapy.

Related Articles Multifunctional mesoporous silica nanoparticles as efficient transporters of doxorubicin and chlorin e6 for chemo-photodynamic combinatorial cancer therapy. J Biomater Appl. 2018 Jan 01;:885328218758925 Authors: Sun JH, Zhang W, Zhang DY, Shen J, Tan CP, Ji LN, Mao ZW Abstract A multimodal nanocarrier based on mesoporous silica nanoparticles (MSNs) is developed to co-delivery photosensitizer chlorin e6 (Ce6) and chemotherapeutic agent doxorubicin (Dox) for cancer combination therapy. Ce6 was covalently conjugated with mesoporous silica nanoparticles, which could increase the loading efficiency, and allowed for photodynamic therapy. Doxorubicin was loaded into the pores of mesoporous silica nanoparticles to afford the dual drug delivery system [email protected] These hybrid nanoparticles have an average diameter of about 100 nm and slightly negative charge of about -17 mV. The [email protected] nanoparticles could efficiently enter into cancer cells. The cellular reactive oxygen species level in treated cells increased about 17 times, upon 660 nm light irradiation (10 mW/cm2, 2 min). More importantly, [email protected] exhibited excellent synergistic effect through combining chemotherapy and photodynamic therapy against A549 lung cancer cells. Our work provides an effective strategy for anticancer drug delivery and combination therapy. PMID: 29448866 [PubMed - as supplied by publisher]

Correlative Studies Unravelling the Possible Mechanism of Cell Death in Tideglusib-Treated Human Ovarian Teratocarcinoma-Derived PA-1 Cells.

Related Articles Correlative Studies Unravelling the Possible Mechanism of Cell Death in Tideglusib-Treated Human Ovarian Teratocarcinoma-Derived PA-1 Cells. J Environ Pathol Toxicol Oncol. 2017;36(4):321-344 Authors: Mathuram TL, Ravikumar V, Reece LM, Sasikumar CS, Cherian KM Abstract This study aims to unravel the use of GSK-3 inhibitors as viable apoptotic inducers for teratocarcinoma-derived ovarian PA-1 cells. MTT assay was carried out to assess inhibitory concentrations of LiCl and TDG. AO/EB staining and Hoechst 33258 staining were employed to assess the damage. Mitochondrial membrane potential (ΔΨm) and ROS generation were assessed with IC50 concentrations of LiCl and TDG. Tumor-related genes (p53, p21, IL-8, TNF-α, MMP-2, Fas-L, Cox-2, and caspase-3) were assessed with 1/4 IC50, 1/2 IC50, IC50 concentrations by semi-quantitative RT- PCR. Cell cycle analysis was performed with IC50 concentration of LiCl and TDG. Western blot analysis was performed for caspase-3, caspase-7, caspase-9, PARP to estimate the possible damage induced by GSK-3 inhibitors and regulation of GSK-3β, pGSK-3β, Cox-2. GSK-3 inhibitors demonstrated a concentration and time-dependent reduction in cell viability, exhibiting significant ROS generation and reduced ΔΨm at their IC50 values. Substantial concentration-dependent gene expression changes with significant upregulation of P21, Cox-2, TNF-α, caspase-3, Fas-L were observed. Protein expression of caspase-3 caspase-7, caspase-9, PARP exhibited significant cleavage in LiCl and TDG-treated cells. Protein expression of Cox-2 was significantly increased in IC50 concentration of TDG. Cell cycle analysis showed significant accumulation of cells at sub-G0-G1. PMID: 29431064 [PubMed - indexed for MEDLINE]

1α,25-dihydroxyvitamin D3 mitigates cancer cell mediated mitochondrial dysfunction in human skeletal muscle cells.

Related Articles 1α,25-dihydroxyvitamin D3 mitigates cancer cell mediated mitochondrial dysfunction in human skeletal muscle cells. Biochem Biophys Res Commun. 2018 02 05;496(2):746-752 Authors: Ryan ZC, Craig TA, Wang X, Delmotte P, Salisbury JL, Lanza IR, Sieck GC, Kumar R Abstract Cancer cachexia is associated with muscle weakness and atrophy. We investigated whether 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3), which has previously been shown to increase skeletal myoblast oxygen consumption rate, could reverse the deleterious effects of tumor cell conditioned medium on myoblast function. Conditioned medium from Lewis lung carcinoma (LLC1) cells inhibits oxygen consumption, increases mitochondrial fragmentation, inhibits pyruvate dehydrogenase activity, and enhances proteasomal activity in human skeletal muscle myoblasts. 1α,25(OH)2D3 reverses the tumor cell-mediated changes in mitochondrial oxygen consumption and proteasomal activity, without changing pyruvate dehydrogenase activity. 1α,25(OH)2D3 might be useful in treatment of weakness seen in association with CC. PMID: 29366785 [PubMed - indexed for MEDLINE]

Total mismatch of diffusion-weighted imaging and susceptibility-weighted imaging in patients with acute cerebral ischemia.

Related Articles Total mismatch of diffusion-weighted imaging and susceptibility-weighted imaging in patients with acute cerebral ischemia. J Neuroradiol. 2017 Sep;44(5):308-312 Authors: Park MG, Yeom JA, Baik SK, Park KP Abstract BACKGROUND AND PURPOSE: Multiple hypointense vessels (MHV) on susceptibility-weighted imaging (SWI) is associated with an increased oxygen demand in acute cerebral ischemia. Occasionally, some patients exhibit extensive MHV on SWI despite of negative diffusion-weighted imaging (DWI), which is a phenomenon called total mismatch DWI-SWI. We analyzed the clinical characteristics and imaging findings in patients with the total DWI-SWI mismatch. MATERIALS AND METHODS: We selected patients with total DWI-SWI mismatch who underwent MRI within 12hours from onset. To evaluate the degree of collateral flow, we graded vessels on post-contrast time-of-flight MR angiography as 3 groups. Perfusion lesion volume was measured using threshold of>6seconds of mean transit time on perfusion-weighted imaging. RESULTS: Total DWI-SWI mismatch was found in 10 (2.7%) out of 370 patients. Four out of 10 patients were excluded due to lack of data on perfusion studies. Hence 6 patients were finally selected in the study. Two patients with internal carotid artery dissection were treated with emergent stenting, one patient with intravenous thrombolysis and mechanical thrombectomy, and two patients with drug-induced hypertension. All of the enrolled patients exhibited extensive MHV on SWI and good collateral flows. The mean perfusion lesion volume was 72.6±15.3ml (range 0-325.0ml). Clinical outcome was favorable in all of the patients (mRS at 3 months, 0). CONCLUSIONS: Our results demonstrate that total mismatch of DWI-SWI is associated with good collateral flow and may be a predictor of good response to treatment in patients with acute cerebral ischemia. PMID: 28579039 [PubMed - indexed for MEDLINE]

Glycolysis regulates the expansion of myeloid-derived suppressor cells in tumor-bearing hosts through prevention of ROS-mediated apoptosis.

Related Articles Glycolysis regulates the expansion of myeloid-derived suppressor cells in tumor-bearing hosts through prevention of ROS-mediated apoptosis. Cell Death Dis. 2017 May 11;8(5):e2779 Authors: Jian SL, Chen WW, Su YC, Su YW, Chuang TH, Hsu SC, Huang LR Abstract Immunotherapy aiming to rescue or boost antitumor immunity is an emerging strategy for treatment of cancers. The efficacy of immunotherapy is strongly controlled by the immunological milieu of cancer patients. Myeloid-derived suppressor cells (MDSCs) are heterogeneous immature myeloid cell populations with immunosuppressive functions accumulating in individuals during tumor progression. The signaling mechanisms of MDSC activation have been well studied. However, there is little known about the metabolic status of MDSCs and the physiological role of their metabolic reprogramming. In this study, we discovered that myeloid cells upregulated their glycolytic genes when encountered with tumor-derived factors. MDSCs exhibited higher glycolytic rate than their normal cell compartment did, which contributed to the accumulation of the MDSCs in tumor-bearing hosts. Upregulation of glycolysis prevented excess reactive oxygen species (ROS) production by MDSCs, which protected MDSCs from apoptosis. Most importantly, we identified the glycolytic metabolite, phosphoenolpyruvate (PEP), as a vital antioxidant agent able to prevent excess ROS production and therefore contributed to the survival of MDSCs. These findings suggest that glycolytic metabolites have important roles in the modulation of fitness of MDSCs and could be potential targets for anti-MDSC strategy. Targeting MDSCs with analogs of specific glycolytic metabolites, for example, 2-phosphoglycerate or PEP may diminish the accumulation of MDSCs and reverse the immunosuppressive milieu in tumor-bearing individuals. PMID: 28492541 [PubMed - indexed for MEDLINE]

The transition from day-to-night activity is a risk factor for the development of CNS oxygen toxicity in the diurnal fat sand rat (Psammomys obesus).

Related Articles The transition from day-to-night activity is a risk factor for the development of CNS oxygen toxicity in the diurnal fat sand rat (Psammomys obesus). Chronobiol Int. 2017;34(5):578-586 Authors: Eynan M, Biram A, Mullokandov M, Kronfeld-Schor N, Paz-Cohen R, Menajem D, Arieli Y Abstract Performance and safety are impaired in employees engaged in shift work. Combat divers who use closed-circuit oxygen diving apparatus undergo part of their training during the night hours. The greatest risk involved in diving with such apparatus is the development of central nervous system oxygen toxicity (CNS-OT). We investigated whether the switch from day-to-night activity may be a risk factor for the development of CNS-OT using a diurnal animal model, the fat sand rat (Psammomys obesus). Animals were kept on a 12:12 light-dark schedule (6 a.m. to 6 p.m. at 500 lx). The study included two groups: (1) Control group: animals were kept awake and active during the day, between 09:00 and 15:00. (2) Experimental group: animals were kept awake and active during the night, between 21:00 and 03:00, when they were exposed to dim light in order to simulate the conditions prevalent during combat diver training. This continued for a period of 3 weeks, 5 days a week. On completion of this phase, 6-sulphatoxymelatonin (6-SMT) levels in urine were determined over a period of 24 h. Animals were then exposed to hyperbaric oxygen (HBO). To investigate the effect of acute melatonin administration, melatonin (50 mg/kg) or its vehicle was administered to the animals in both groups 20 min prior to HBO exposure. After the exposure, the activity of superoxide dismutase, catalase and glutathione peroxidase was measured, as were the levels of neuronal nitric oxide synthase (nNOS) and overall nitrotyrosylation in the cortex and hippocampus. Latency to CNS-OT was significantly reduced after the transition from day-to-night activity. This was associated with alterations in the level of melatonin metabolites secreted in the urine. Acute melatonin administration had no effect on latency to CNS-OT in either of the groups. Nevertheless, the activity of superoxide dismutase and catalase, as well as nitrotyrosine and nNOS levels, were altered in the hippocampus following melatonin administration. On the basis of these results, we suggest that a switch from diurnal to nocturnal activity may represent an additional risk factor for the development of CNS-OT. Utilizing a diurnal animal model may contribute to our understanding of the heightened risk of developing CNS-OT when diving with closed-circuit oxygen apparatus at night. PMID: 28156158 [PubMed - indexed for MEDLINE]

Optimization of Positive End-Expiratory Pressure Targeting the Best Arterial Oxygen Transport in the Acute Respiratory Distress Syndrome: The OPTIPEP Study.

Related Articles Optimization of Positive End-Expiratory Pressure Targeting the Best Arterial Oxygen Transport in the Acute Respiratory Distress Syndrome: The OPTIPEP Study. ASAIO J. 2017 Jul/Aug;63(4):450-455 Authors: Chimot L, Fedun Y, Gacouin A, Campillo B, Marqué S, Gros A, Delour P, Bedon-Carte S, Le Tulzo Y Abstract The optimal setting for positive end-expiratory pressure (PEEP) in mechanical ventilation remains controversial in the treatment of acute respiratory distress syndrome (ARDS). The aim of this study was to determine the optimum PEEP level in ARDS, which we defined as the level that allowed the best arterial oxygen delivery (DO2). We conducted a physiologic multicenter prospective study on patients who suffering from ARDS according to standard definition and persistent after 6 hours of ventilation. The PEEP was set to 6 cm H2O at the beginning of the test and then was increased by 2 cm H2O after at least 15 minutes of being stabilized until the plateau pressure achieved 30 cm H2O. At each step, the cardiac output was measured by transesophageal echocardiography and gas blood was sampled. We were able to determine the optimal PEEP for 12 patients. The ratio of PaO2/FiO2 at inclusion was 131 ± 40 with a mean FiO2 of 71 ± 3%. The optimal PEEP level was lower than the higher PEEP despite a constant increase in SaO2. The optimal PEEP levels varied between 8 and 18 cm H2O. Our results show that in patients with ARDS the optimal PEEP differs between each patient and require being determined with monitoring. PMID: 27984319 [PubMed - indexed for MEDLINE]

Copper Exchange and Redox Activity of a Prototypical 8-Hydroxyquinoline: Implications for Therapeutic Chelation.

Related Articles Copper Exchange and Redox Activity of a Prototypical 8-Hydroxyquinoline: Implications for Therapeutic Chelation. Inorg Chem. 2016 Aug 01;55(15):7317-9 Authors: Mital M, Zawisza IA, Wiloch MZ, Wawrzyniak UE, Kenche V, Wróblewski W, Bal W, Drew SC Abstract The N-truncated β-amyloid (Aβ) isoform Aβ4-x is known to bind Cu(2+) via a redox-silent ATCUN motif with a conditional Kd = 30 fM at pH 7.4. This study characterizes the Cu(2+) interactions and redox activity of Aβx-16 (x = 1, 4) and 2-[(dimethylamino)-methyl-8-hydroxyquinoline, a terdentate 8-hydroxyquinoline (8HQ) with a conditional Kd(CuL) = 35 pM at pH 7.4. Metal transfer between Cu(Aβ1-16), CuL, CuL2, and ternary CuL(NIm(Aβ)) was rapid, while the corresponding equilibrium between L and Aβ4-16 occurred slowly via a metastable CuL(NIm(Aβ)) intermediate. Both CuL and CuL2 were redox-silent in the presence of ascorbate, but a CuL(NIm) complex can generate reactive oxygen species. Because the NIm(Aβ) ligand will be readily exchangeable with NIm ligands of ubiquitous protein His side chains in vivo, this class of 8HQ ligand could transfer Cu(2+) from inert Cu(Aβ4-x) to redox-active CuL(NIm). These findings have implications for the use of terdentate 8HQs as therapeutic chelators to treat neurodegenerative disease. PMID: 27409140 [PubMed - indexed for MEDLINE]