Reliable and specific detection of Acanthamoeba spp. in dishcloths using quantitative real-time PCR assay.

Acanthamoeba spp., are ubiquitous protist which belongs to Free-Living Amoeba (FLA) group, is considered as causal agent of side-threatening keratitis or fatal encephalitis among other human infections. Besides, this parasite has been reported as host for other microorganisms important to human health such as Campylobacter spp. or Vibrio spp. among others. This role of Acanthamoeba as pathogen and environmental phagocyte has increased the reports confirming its presence in human related environments, acting as a water quality indicator. Considering the tide relationship between water and kitchen environments, and the high prevalence of Acanthamoeba in water sources, the present study aims to establish a quick and accurate protocol based on DNA extraction and a real time qPCR assay to detect Acanthamoeba spp. in dishcloths. The procedure has been validated by processing 17 used dishcloths. Our findings demonstrated the high sensitivity of the qPCR assay used which was capable of detecting up to one Acanthamoeba from an in vitro contaminated dishcloth. The protocol accurately detected 64.7% of positive samples for Acanthamoeba spp, (in 4 samples DNA concentrations corresponded to 1-102 amoebae). Our findings demonstrate the importance of FLA surveillance by efficient and sensitive methods since one amoeba is capable of colonizing human related food environments such as kitchens sinks and could be a potential source of infection.

Arterial vascularization of the mandible and soft tissues. Anatomic study.

PURPOSE: The literature has for too long described the arterial supply of the mandible as coming from a single artery, the inferior alveolar artery, and being of the terminal type. Rather, it appears to come from an extensive and complex arterial network dependent on the lingual, facial, and maxillary arteries and their collateral branches. Our study aims to confirm and demonstrate the arterial vascular richness of the mandible and to establish arterial mapping. METHODS: The arterial vascularization of the mandible was revealed in six anatomic specimens after performing selective injections of the lingual, facial, and maxillary arteries with different dyes. A specimen was injected intra-arterially with colored latex at the level of the maxillary artery for a morphometric study. RESULTS: Eighteen selective arterial injections were performed on six anatomic specimens. The mucocutaneous, musculoperiosteal, and intramedullary vascularizations were analyzed. Each of the arteries has a defined and delimited cutaneo-mucous vascular territory. The facial and maxillary arteries supply the musculoperiosteal vascularization of the mandible from the condyle to the symphysis. The lingual artery supplies only the inner cortex of the parasymphyseal and symphyseal regions. The facial and maxillary arteries provide intramedullary vascularization from the angle of the mandible to the parasymphysis. The vascularization of the symphysis depends on the facial artery. No staining was found in the condyle region. Neoprene latex injection was performed on an anatomic specimen, revealing a permeable anastomosis between the inferior alveolar and facial arteries. CONCLUSION: The arterial vascularization of the mandible is dependent on the maxillary, facial, and lingual arteries. This is a network vasculature. This study makes it possible to establish an arterial map of the mandible. The presence of an anastomosis between the inferior alveolar artery and the facial artery confirms the existence of dynamic and borrowed vascularization. Knowledge of this arterial system makes it possible to adapt maxillofacial surgical care and to anticipate possible intraoperative complications.

Racial disparity and prognosis in patients with mouth and oropharynx cancer in Brazil.

BACKGROUND: Oral and oropharyngeal cancer (OPC) is an important cause of morbidity and mortality worldwide. Populations in situations of social vulnerability tend to have higher incidences of cancer, a higher proportion of late diagnosis, greater difficulties in accessing health services, and, consequently, worse prognosis. The aim of this study was to evaluate the relationship between race/skin color and OPC prognosis in Brazil. MATERIAL AND METHODS: This is a cross-sectional epidemiological study using OPC data from the National Cancer Institute between the years 2000 and 2019. The selected variables were: gender, race/skin color, age, education, smoking and alcohol consumption, stage of the disease and disease status at the end of the 1st treatment. RESULTS: 154,214 cases were recorded. Black men, in the 6th decade of life, were the most affected population. Blacks had a lower level of education when compared to non-blacks (p<0.001). Blacks were more exposed to smoking and alcohol consumption (p<0.001). At the time of diagnosis, the black population was at the most advanced stage when compared to non-blacks (p<0.001). At the end of the 1st treatment, more black patients had disease in progression, as well as more black patients died (p<0.001). CONCLUSIONS: Blacks had a worse prognosis for OPC in Brazil. Despite the limitations, these results are important to elucidate the scenario of health disparities in relation to the race/skin color of the Brazilian population.

Is Dexamethasone superior to Ketorolac in reducing pain, swelling and trismus following mandibular third molar removal? A split mouth triple-blind randomized clinical trial.

BACKGROUND: The preemptive use of anti-inflammatory drugs, such as corticosteroids and NSAIDs, has the potential to reduce pain, swelling and trismus following oral surgery. The aim of this study was to compare the efficacy of dexamethasone and ketorolac tromethamine in reducing pain, swelling and trismus after mandibular third molar removal. MATERIAL AND METHODS: The researches implemented a triple-blind, randomized clinical trial. The study was conducted with ASA I individuals aging between 18 and 35 years, which were randomized and submitted to two interventions, one with 8mg dexamethasone and the other with 20mg ketorolac tromethamine given 1h before the procedure. The primary predictor variable was the use of dexamethasone or ketorolac. The primary outcome variable was the postoperative pain level, measured with a Visual Analogue Scale. The secondary outcome variables were the amount of rescue analgesic consumed, swelling and trismus. Repeated-measures ANOVA and t-test for paired samples were used to compare the means. Significance was set at p < 0.05. RESULTS: Fifty individuals were randomized and allocated to intervention, and the sample was composed of 40 subjects who completed the study (27 female and 13 male). Dexamethasone, when compared to ketorolac tromethamine, showed a significantly higher reduction in pain level at 8h, 16h, 24h, 32h, 40h and 72h, in swelling and trismus at 24h, 48h, 72h and 7 days and in total number of rescue analgesics taken up to 72h postoperative (p < 0.05). CONCLUSIONS: The clinical performance of dexamethasone in controlling pain, swelling and trismus after mandibular third molar removal was superior to ketorolac tromethamine's.

High prevalence of oral potentially malignant disorders and risk factors in a semi-urban brazilian city: a population-based cross-sectional study.

BACKGROUND: Oral Potentially Malignant Disorders (OPMDs) are defined as lesions with a greater likelihood of progressing to cancer. Population-based studies that evaluate the prevalence of OPMDs are scarce in Brazil. The aim of the present study was to determine the prevalence of OPMDs and associated risk factors in a semi-urban Brazilian population. MATERIAL AND METHODS: This is a cross-sectional study, whose universe included individuals aged 40 years or older residing in a medium-sized city of northeastern Brazil. Data collection was divided into two steps: interview and oral examination. The outcome variable was the presence of OPMDs. The predictor variables were sociodemographic characteristics and risk habits. The bivariate analysis was performed through chi-square test. The crude prevalence ratios (PR) and its respective 95% confidence intervals (CI) were calculated. Poisson regression analysis with robust variance was used to calculate adjusted PRs and 95% CI. RESULTS: Three hundred fourteen individuals were included in the study. When asked about risk habits, 58.9% reported being current smokers or ex-smokers and 62.2% reported being current drinkers or ex-drinkers. The prevalence of OPMDs was 7.6% and was significantly higher among individuals with black skin color (p < 0.001), alcohol users (p = 0.017), and individuals with both tobacco and alcohol habits (p = 0.012). CONCLUSIONS: Therefore, the population in the present study had a high frequency of risk habits associated with PMDs of the oral cavity.

Prevalence of ulcerative stomatitis in arbovirus infections in a Brazilian Northeast population.

BACKGROUND: Although there are no population-based studies that support an association, there are reports in the literature of mucocutaneous, vesiculobullous and ulcerated lesions in the oral mucosa in cases of arbovirus infection. The aim of this study is to analyze the prevalence of ulcerative stomatitis in individuals affected by arboviruses in a population of the municipality of Arcoverde, Pernambuco, Brazil. MATERIAL AND METHODS: 1,003 people living in an area assigned to a Primary Health Care Unit were interviewed. A structured questionnaire was used for data collection, with questions about sociodemographic variables, residence conditions, general health information, as well as information about the general signs and symptoms of arboviruses and specifically about oral lesions. RESULTS: Of the 1,003 individuals interviewed, 815 (81.25%) were infected by one or more arboviruses. Of these, 147 (18%) reported ulcerated oral lesions during arbovirus infections. The association between arbovirus infections and the presence of ulcerated oral lesions was statistically significant (p = 0.000). CONCLUSIONS: In these cases, the ulcerated lesions on the oral mucosa appear to be associated with arbovirus infection, especially Chikungunya, although the pathophysiological mechanisms are not defined, and the studies are not sufficient to confirm this association.

Infrared Spectroscopy of Matrix-Isolated Neutral and Ionized Anthracoronene in Argon.

The matrix-isolated mid-IR (MIR) spectrum of neutral and ionized anthracoronene (C36H18, AnthCor) in argon has been measured experimentally, compared to the spectrum of its parent molecules, coronene and anthracene, and analyzed by comparison to a theoretical spectrum computed using density functional theory (DFT). The experimental and theoretical band positions generally agree within 0-10 cm-1. Anthracoronene exhibits extremely intense cation and anion bands around 1330 and 1318 cm-1. The intensity of these two bands approaches what is traditionally observed over the entire 1000-1600 cm-1 range for a typical PAH cation or anion. The matrix-isolated near-IR (NIR) through overlap region (OVR) spectrum of ionized AnthCor in argon has been reported for the first time and compared to the spectrum of its parent molecules, coronene and anthracene. The spectrum of AnthCor contains a very strong electronic transition around 6175 cm-1, placing it outside the range of the electronic transitions typically observed for PAHs. Anthracoronene is one of the few PAHs studied to date which has exhibited the formation of anions upon UV photolysis.

Prescribing errors intercepted by pharmacist intervention in care of patients hospitalised with breast and gynaecological cancer at a Brazilian teaching hospital.

Oncologic inpatients often require multiple drug therapy. They may be at higher risk of experiencing prescribing errors, which pharmacist interventions may help to avoid. This study aimed to evaluate the types of prescribing errors, pharmaceutical interventions and differences in clinical significance, in prescriptions for hospitalised patients with breast and gynaecological cancer. A cross-sectional, prospective study was conducted at the oncology ward of a clinic specialised in breast and gynaecology cancer. A clinical pharmacist analysed prescriptions, identified errors, performed interventions and classified clinical significance. A total of 1,874 prescriptions of 248 patients were evaluated; 11.5% prescriptions were involved at least in one prescribing error, totalising 283 errors. The most common error was unsafe medication due to drug interaction (89[31.4%]). Drugs for the alimentary tract and metabolism, and nervous system were the most involved in errors with statistical association (p = .0246 and p = .0002 respectively). Of the 294 interventions, 73.5% were accepted. The clinical significance of prescribing errors and interventions were classified as significant and very significant respectively. The pharmacist interventions obtained a good acceptance rate and impact significantly, avoiding prescribing errors classified as significant.

Biocompatible hydrophilic brushite coatings on AZX310 and AM50 alloys for orthopaedic implants.

Dicalcium phosphate dihydrate (DCPD) brushite coating with flake like crystal structure for the protection of AZX310 and AM50 magnesium (Mg) alloys was prepared through chemical deposition treatment. Chemical deposition treatment was employed using Ca(NO3)2·4H2O and KH2PO4 along with subsequent heat treatment. The morphological results revealed that the brushite coating with dense and uniform structures was successfully deposited on the surface of AZX310 and AM50 alloys. The X-ray diffraction (XRD) patterns and Attenuated total reflectance infrared (ATR-IR) spectrum also revealed the confirmation of DCPD layer formation. Hydrophilic nature of the DCPD coatings was confirmed by Contact angle (CA) measurements. Moreover, electrochemical immersion and in vitro studies were evaluated to measure the corrosion performance and biocompatibility performance. The deposition of DCPD coating for HTI AM50 enables a tenfold increase in the corrosion resistance compared with AZX310. Hence the ability to offer such significant improvement in corrosion resistance for HTI AM50 was coupled with more bioactive nature of the DCPD coating is a viable approach for the development of Mg-based degradable implant materials.

Acrocomia aculeata oil: Beneficial effects on cyclophosphamide-induced reproductive toxicity in male rats.

This study aimed to evaluate the effects of the extracted oil of Acrocomia aculeata pulp in preventing or mitigating the reproductive toxicity induced by cyclophosphamide (CP) in male rats. Adult male rats were segregated into seven groups that received vehicle, 100 mg/kg/day of CP, or 10 mg/kg/day of ß-carotene or 3 or 30 mg/kg/day of A. aculeata oil co-administered with CP. A. aculeata oil exhibited a high content of ß-carotene. CP treatment induced reproductive toxicity in the animals, as it changed the reproductive organs weight, hormone levels, sperm counts and testicular histology. In contrast, co-administration of A. aculeata improved CP-induced alterations in these parameters. A. aculeata oil also increased the gene Ckit expression and normalised the antioxidant enzymes levels which were changed by CP. The A. aculeata oil is capable of protecting the male reproductive system from the adverse effects of CP, possibly by acting as an antioxidant and increasing the Ckit gene expression.

Treatment of earlobe keloids by surgical excision and cryosurgery.

BACKGROUND: The long-term results of keloid treatments remain poor. OBJECTIVE: To assess the long-term efficacy of a technique combining surgical excision and immediate cryosurgery in patients with ear keloids. METHODS: A retrospective study was performed between January 2001 and June 2011. All patients referred for treatment of an ear keloid and undergoing subsequent surgical excision followed by immediate freezing of the postoperative wound using cryosurgery were included. The primary end-point was the number of patients who achieved major flattening of the keloid (defined as a reduction of more than 80% of the keloid) at the time of the study after a minimum follow-up of 24 months after treatment. RESULTS: Sixty-six patients with a total of 97 keloids were included. Median follow-up time after treatment was 43 months. 'Major' flattening was observed in 69 keloids (71%). Fifty-six of these lesions (81%) were treated with one session and 13 (19%) required a second session after keloid recurrence. Fifteen lesions (15%) were considered 'treatment failure', including 11 keloids in eight patients who were lost to follow-up and four keloids which achieved less than 30% reduction of their surface. Thirteen other keloids were evaluated as displaying significant or moderate improvement. Treatment side-effects were partial amputation of the ear lobe in three patients with a very large keloid of the ear lobe and hypopigmentation in five patients. LIMITATION: Retrospective study. CONCLUSION: The combination of surgical excision and cryosurgery can be considered for the treatment of large ear keloids.

Construction and characterization of organic photovoltaic cells sensitized by Chrysanthemum based natural dye.

In this work, natural dyes from three different species of the same flower family (Chrysanthemum), which containing anthocyanin were extracted and properly prepared to be used as photosensitizers in DSSCs construction. The cells were fabricated with titanium dioxide nanoparticles (TiO2) for the photoanodes, whereas platinum electrodes were used for the photocathodes. To understand the behavior of light absorption in addition to the coloring components present in the dyes and the molecular functional groups present in the samples, the UV-Vis absorption spectroscopy and FTIR spectroscopy were used respectively. The performance and efficiency of solar cells were evaluated to establish the photovoltaic criteria for each DSSC built. Through electrochemical characterizations, it was possible to notice that the highest photovoltaic conversion efficiency was obtained with the Chrysanthemum Violet (CV) cell, with efficiency (η) of 1.348%, compared to 1.229% and 0.485% for the Chrysanthemum Green (CG) and Chrysanthemum Blue (CB) cells, respectively. The CV cell also has the highest open circuit voltage (VOC) at 0.58 V. The results corroborate to present the organic solar cells as a viable option for the electric energy generation.

Acute mastoiditis in children: 10 years experience in a French tertiary university referral center.

Acute mastoiditis have been increasingly reported in the last decade, with bacteriologic modifications and new therapeutic guidelines. This study is a retrospective review of 36 children hospitalized for acute mastoiditis in a French tertiary university referral center from 1999 to 2009, to assess incidence, bacteriology of pathogens and management. There were 10 periosteitis and 26 subperiosteal abscesses. There was a trend toward increased incidence over the past 10 years. The mean age of the patients was 31.8 months. A total of 63.2% children received 7.2 days antibiotic prior to hospitalization for acute otitis media, with sensitive pathogens in 80%. The pathogens were Streptococcus pneumoniae (36.1%), S. pyogenes A (13.9%), Staphylococcus coagulase-negative (13.9%), Pseudomonas aeruginosa (8.3%), Fusobacterium necroforum (8.3%) and Haemophiluss influenzae (2.8%). Cultures were negative in 16.7%. All patients received intravenous antibiotics. Eleven patients underwent bilateral myringotomy with or without tympanostomy tubes. Mastoidectomy was performed in 24 patients. Decrease in the length of hospitalization and delay from admission to surgery were significantly correlated. We observed a trend in the increase of acute mastoiditis at our center. The pathogens were dominated by S. pneumoniae. F. necroforum and P. aerguginosae were pathogens found in children over 2 years of age. Mastoidectomy was performed in 92.3% of subperiostal abscesses. However, there has been a trend toward conservative nonsurgical treatment in recent reported studies and further prospective studies are warranted to evaluate the long-term sequelae.

SWI as an Alternative to Contrast-Enhanced Imaging to Detect Acute MS Lesions.

BACKGROUND AND PURPOSE: Acute inflammatory activity of MS lesions is traditionally assessed through contrast-enhanced T1-weighted MR images. The aim of our study was to determine whether a qualitative evaluation of non-contrast-enhanced SWI of new T2-hyperintense lesions might help distinguish acute and chronic lesions and whether it could be considered a possible alternative to gadolinium-based contrast agents for this purpose. MATERIALS AND METHODS: Serial MR imaging studies from 55 patients with MS were reviewed to identify 169 new T2-hyperintense lesions. Two blinded neuroradiologists determined their signal pattern on SWI, considering 5 categories (hypointense rings, marked hypointensity, mild hypointensity, iso-/hyperintensity, indeterminate). Two different blinded neuroradiologists evaluated the presence or absence of enhancement in postcontrast T1-weighted images of the lesions. The Fisher exact test was used to determine whether each category of signal intensity on SWI was associated with gadolinium enhancement. RESULTS: The presence of hypointense rings or marked hypointensity showed a strong association with the absence of gadolinium enhancement (P < .001), with a sensitivity of 93.0% and a specificity of 82.9%. The presence of mild hypointensity or isohyperintensity showed a strong association with the presence of gadolinium enhancement (P < .001), with a sensitivity of 68.3% and a specificity of 99.2%. CONCLUSIONS: A qualitative analysis of the signal pattern on SWI of new T2-hyperintense MS lesions allows determining the likelihood that the lesions will enhance after administration of a gadolinium contrast agent, with high specificity albeit with a moderate sensitivity. While it cannot substitute for the use of contrast agent, it can be useful in some clinical settings in which the contrast agent cannot be administered.

A critical appraisal of evidence in the use of preprocedural mouthwash to avoid SARS-CoV-2 transmission during oral interventions.

OBJECTIVE: The study aimed to review and report the current evidence supporting the use of mouthwashes as a preprocedural protocol on dental offices. MATERIALS AND METHODS: This study is a secondary one that performed a comprehensive literature search of scientific studies published up to 10th August 2020 in PubMed, Scopus, Web of Science, and Scientific Electronic Library Online (Scielo) databases. The electronic search strategy was performed using free text and DeCS/MeSH terms. RESULTS: Only five studies were included in this work, despite 140 studies that were identified with the research strategy. In vivo studies were carried out in two works, in vitro studies were described in two papers, and a in silico approach was used in one work. No cetylpyridinium chloride studies were identified, while chlorhexidine and povidone studies were more studied. CONCLUSIONS: There is reduced evidence about how preprocedural mouthwashes decrease SARS-CoV-2 salivary load.

Photoelectric performance evaluation of DSSCs using the dye extracted from different color petals of Leucanthemum vulgare flowers as novel sensitizers.

In this work, the natural flower extracted dyes containing luteolin were prepared using three different specimens from daisy flowers family (Leucanthemum vulgare), namely yellow daisy, purple daisy and wine daisy, according to the color of its petals. Moreover, DSSCs were fabricated using nanosized titanium dioxide (TiO2) as an anode; for the photocathodes, two different specimens were used: i) graphite electrode and ii) platinum electrode. To recognize the light absorption behavior, the existence of anchoring groups and coloring components of the extracted dyes were determined using absorption spectroscopy. The surface roughness of the photoanodes and cathodes were examined using atomic force microscope (AFM). The photovoltaic performance and efficiency of assembled DSSCs were evaluated to realize the influence of TiO2 photoanodes on interaction of the Leucanthemum vulgare extracted dye molecules with graphite or platinum photocathodes. DSSCs fabricated with platinum cathode show higher conversion efficiency (η) of 0.6%, 0.4% and 0.8% for the yellow daisy, wine daisy and purple daisy, respectively. DSSCs sensitized with daisy wine dye showed highest open-circuit voltage (Voc) of 520 mV and efficiency of 0.79% and 0.88%, for the graphite and platinum cathodes, respectively. These results showed that the DSSCs, using daisy flowers extracts as efficient photosensitizers, are suitable for the fabrication of environmentally safe, inexpensive, clean and renewable energy.

Impact of discontinuation of antithrombotic therapy after surgery for chronic subdural hematoma.

INTRODUCTION: The management of antithrombotic therapy (AT) after surgery for chronic subdural hematoma (cSDH) requires taking account of the balance of risk between hemorrhage recurrence (HR) and the prophylactic thromboembolic effect (TE). The goal of the present study was to evaluate the prevalence of vascular events (VE: TE and/or HR) in the first 3 postoperative months after cSDH evacuation in patients previously treated by AT. The impact of AT resumption was also evaluated. PATIENTS AND METHODS: This observational prospective multicenter collaborative study (14 French neurosurgery centers) included patients with cSDH treated by AT and operated on between May 2017 and March 2018. Data collection used an e-CRF, and was principally based on an admission questionnaire and outcome/progression at 3 months. RESULTS: In this cohort of 211 patients, VE occurred in 58 patients (27.5%): HR in 47 (22.3%), TE in 17 (8%), with mixed event in 6 cases (2%). Median overall time to onset of complications 26 days±31.5, and specifically 43.5 days±29.25 for HR. Non-resumption of AT significantly increased the relative risk of VE [OR: 4.14; 95% CI: 2.08 - 8.56; P <0.001] and especially of TE [OR: 7.5; 95% CI: 1.2 - 42; P<0.001]. The relative risk of HR was significantly increased when AT was resumed at less than 30 days (P=0.015). CONCLUSION: The occurrence of VE in patients operated on for cSDH and previously treated by AT was statistically significant (27.5%). HR was the most common event (22.3%), whereas TE accounted for only the 8%, although with shorter time to onset. In order to prevent TE risk, AT should be restarted after 30 days, as HR risk is greatly decreased beyond this time.

Technetium-99m-labeled lapachol as an imaging probe for breast tumor identification. / Lapachol marcado con tecnecio 99m como sonda de imágenes para la identificación de tumores de mama.

OBJECTIVE: Breast cancer is a health problem worldwide with high incidence and mortality rates. It is well known that the development of more sensitive and specific diagnostic methods is of great importance since an early diagnosis is essential to successfully treat tumors. Lapachol is a natural compound, belonging to the naphthoquinone group that has been widely used in traditional medicine to treat various illnesses, including cancer. The aim of this study was to evaluate technetium-99m (99mTc) labeled lapachol as an imaging probe for breast cancer identification. METHODS: To achieve this purpose, lapachol was labeled with 99mTc, radiochemical purity and in vitro stability were determined. Blood clearance, in healthy mice, and biodistribution, in 4T1 tumor-bearing mice, were also evaluated. RESULTS: Lapachol was successfully labeled with 99mTc, with high values of radiochemical yield (95.9±3.4%). In vitro stability showed that the radiolabeled complex remained stable for up to 24h, with values above 90% for both saline and plasma (95.6±3.6% and 96.4±1.7%, respectively). The radiolabeled complex decays in a biphasic manner, with a half-life of distribution and elimination equal to 3.3 and 50.0min, respectively. Biodistribution and scintigraphic images showed high uptake in organs of excretion (kidneys, liver, and intestine). It could be also noted that tumor uptake was higher than the muscle at all time points. Tumor-to-muscle ratio reaches ∼4.5 at 24h after administration. CONCLUSION: These findings suggest that 99mTc-lapachol can be a potential diagnostic agent for breast tumors.

Photochemistry of coronene in cosmic water ice analogs at different concentrations.

This work presents the photochemistry of ultraviolet (UV) irradiated coronene in water ices at 15 K, studied using mid-infrared Fourier transform (FTIR) spectroscopy for C24H12:H2O at concentrations of (1:50), (1:150), (1:200), (1:300) and (1:400). Previous UV irradiation studies of anthracene:H2O, pyrene:H2O and benzo[ghi]perylene:H2O ices at 15 K have shown that aromatic alcohols and ketones, as well as CO2 and H2CO are formed at very low temperatures. Like-wise, here, in addition to the coronene cation, hydroxy-, keto-, and protonated coronene (coronene-H+) are formed. The rate constants for the decay of neutral coronene and for the formation of photoproducts have been derived. It is shown that PAHs and their UV-induced PAH:H2O photoproducts have mid-infrared spectroscopic signatures in the 5-8 µm region that can contribute to the interstellar ice components described by Boogert et al. (2008) as C1-C5. Our results suggest that oxygenated and hydrogenated PAHs could be in UV-irradiated regions of the ISM where water-rich ices are important.

Soluble NADH-cytochrome b5 reductase from rabbit liver cytosol: partial purification and characterization.

A soluble form of NADH-cytochrome b5 reductase (NADH: ferricytochrome b5 oxidoreductase, EC 1.6.2.2) was found in the cytosolic fraction of rabbit liver. The partially purified enzyme was strictly specific for NADH. It catalyzed the reduction of several substrates such as the methemoglobin-ferrocyanide complex (Hegesh, E. and Avron, M. (1967) Biochim. Biophys. Acta 146, 91-101) (apparent Km: 8 micrometer), potassium ferricyanide (apparent Km: 10 micrometer) and ferricytochrome b5 (apparent Km: 15 micrometer). Upon acrylamide gel isoelectro-focusing followed by specific staining, the enzyme was resolved into four bands (isoelectric pH: 7.05, 6.70, 6.50 and 6.30). The optimum pH of activity with ferricytochrome b5 as a substrate was 6.5. The estimated molecular weight was 25 000--30 000. The enzyme was unsensitive to cyanide. It was strongly inhibited by p-hydroxymercuribenzoate. The cytosolic liver cytochrome b5 reductase was immunologically related to the soluble cytochrome b5 reductase from human and rabbit red-cells, and to the microsomal cytochrome b5 reductase from rabbit liver.