141 research outputs found

    8-Oxo-7,8-dihydroguanine and 8-oxo-7,8-dihydro-2\u27-deoxyguanosine concentrations in various human body fluids: implications for their measurement and interpretation

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    8-Oxo-7,8-dihydro-2\u27-deoxyguanosine (8-oxodGuo) is the most investigated product of oxidatively damaged DNA lesion that has been associated with the development of aging, cancer and some degenerative diseases. Here, we present the first liquid chromatography-tandem mass spectrometry method that enables the simultaneous measurement of its repair products in plasma and saliva, namely 8-oxo-7,8-dihydroguanine (8-oxoGua) and 8-oxodGuo. Using this method, we investigated the underlying transport mechanism of the repair products of oxidatively damaged DNA between cellular compartments and biological matrices. Plasma, saliva and urine samples were collected concurrently from 57 healthy subjects. Various deproteinization methods were evaluated, and the precipitants acetonitrile and sodium hydroxide-methanol were, respectively, selected for plasma and saliva samples due to their effect on recovery efficiencies and chromatography. The mean baseline concentrations of 8-oxoGua and 8-oxodGuo in plasma were demonstrated to be 0.21 and 0.016 ng/mL, respectively, while in saliva they were 0.85 and 0.010 ng/mL, respectively. A relatively high concentration of 8-oxoGua was found in saliva with a concentration factor (CF, concentration ratio of saliva to plasma) of 4 as compared to that of 8-oxodGuo (CF: 0.6), implying that 8-oxoGua in plasma may be actively transported to saliva, whereas 8-oxodGuo was most dependent on a passive diffusion. Good correlations between urine and plasma concentrations were observed for 8-oxoGua and 8-oxodGuo, suggesting that blood was a suitable matrix in addition to urine. Significant correlation between 8-oxoGua and 8-oxodGuo in urine was only observed when the concentrations were not corrected for urinary creatinine, raising the issue of applicability of urinary creatinine to adjust 8-oxoGua concentrations

    8-Oxo-7,8-dihydroguanine and 8-oxo-7,8-dihydro-2\u27-deoxyguanosine concentrations in various human body fluids: implications for their measurement and interpretation

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    8-Oxo-7,8-dihydro-2\u27-deoxyguanosine (8-oxodGuo) is the most investigated product of oxidatively damaged DNA lesion that has been associated with the development of aging, cancer and some degenerative diseases. Here, we present the first liquid chromatography-tandem mass spectrometry method that enables the simultaneous measurement of its repair products in plasma and saliva, namely 8-oxo-7,8-dihydroguanine (8-oxoGua) and 8-oxodGuo. Using this method, we investigated the underlying transport mechanism of the repair products of oxidatively damaged DNA between cellular compartments and biological matrices. Plasma, saliva and urine samples were collected concurrently from 57 healthy subjects. Various deproteinization methods were evaluated, and the precipitants acetonitrile and sodium hydroxide-methanol were, respectively, selected for plasma and saliva samples due to their effect on recovery efficiencies and chromatography. The mean baseline concentrations of 8-oxoGua and 8-oxodGuo in plasma were demonstrated to be 0.21 and 0.016 ng/mL, respectively, while in saliva they were 0.85 and 0.010 ng/mL, respectively. A relatively high concentration of 8-oxoGua was found in saliva with a concentration factor (CF, concentration ratio of saliva to plasma) of 4 as compared to that of 8-oxodGuo (CF: 0.6), implying that 8-oxoGua in plasma may be actively transported to saliva, whereas 8-oxodGuo was most dependent on a passive diffusion. Good correlations between urine and plasma concentrations were observed for 8-oxoGua and 8-oxodGuo, suggesting that blood was a suitable matrix in addition to urine. Significant correlation between 8-oxoGua and 8-oxodGuo in urine was only observed when the concentrations were not corrected for urinary creatinine, raising the issue of applicability of urinary creatinine to adjust 8-oxoGua concentrations

    Structural Elements Regulating AAA+ Protein Quality Control Machines

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    Members of the ATPases Associated with various cellular Activities (AAA+) superfamily participate in essential and diverse cellular pathways in all kingdoms of life by harnessing the energy of ATP binding and hydrolysis to drive their biological functions. Although most AAA+ proteins share a ring-shaped architecture, AAA+ proteins have evolved distinct structural elements that are fine-tuned to their specific functions. A central question in the field is how ATP binding and hydrolysis are coupled to substrate translocation through the central channel of ring-forming AAA+ proteins. In this mini-review, we will discuss structural elements present in AAA+ proteins involved in protein quality control, drawing similarities to their known role in substrate interaction by AAA+ proteins involved in DNA translocation. Elements to be discussed include the pore loop-1, the Inter-Subunit Signaling (ISS) motif, and the Pre-Sensor I insert (PS-I) motif. Lastly, we will summarize our current understanding on the inter-relationship of those structural elements and propose a model how ATP binding and hydrolysis might be coupled to polypeptide translocation in protein quality control machines

    Safety and effectiveness of new embolization microspheres SCBRM for intermediate-stage hepatocellular carcinoma: A feasibility study

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    Transarterial chemoembolization (TACE) is, currently, the recommended treatment for hepatocellular carcinoma (HCC). However, long-term chemoembolization triggers the inflammatory response and may lead to postembolization syndrome (PES). Although several types of degradable microspheres have been developed to reduce drug toxicity and PES incidence, the clinical outcomes remain unsatisfactory. Previously, we have developed a new type of spherical, calibrated, biodegradable, radiopaque microspheres (SCBRM) and demonstrated their safety and efficacy in a pig model. Thus, the goal of this feasibility study was to determine the clinical safety and efficacy of the new SCBRM in intermediate-stage HCC patients. In this study, 12 intermediate-stage HCC patients underwent TACE using SCBRM with a calibrated size of 100–250 μm. The disease control rates at 1 month and 3 months after TACE-SCBRM treatment were 100% and 75.0%, respectively. The objective response rates at 1 month and 3 months after treatment were 66.7% and 58.3%, respectively. Very few adverse events were observed with one patient developing nausea. One day after the treatment, alanine aminotransferase, alanine aminotransferase, and total bilirubin levels were slightly elevated in the patients, but all returned to baseline on day 7. The median and mean overall survival times were 33 months (interquartile range, 12.8–42.0) and 29.2 ± 14.3 months, respectively. The 1-year and 2-year survival rates were 91.7% and 58.3%, respectively. In conclusion, TACE with the new SCBRM microspheres is clinically safe and effective, and it represents a promising approach in the management of intermediate-stage HCC

    Impact of cognitive behavior therapy on osteoarthritis-associated pain, insomnia, depression, fatigue, and physical function in patients with knee/hip osteoarthritis: A systematic review and meta-analysis of randomized controlled trials

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    BackgroundThis meta-analysis aimed at evaluating the efficacy of cognitive behavior therapy (CBT) against osteoarthritis-associated symptoms in patients with knee/hip osteoarthritis.MethodsMedline, PubMed, Cochrane Library, and EMBASE databases were searched from inception to July 2022 to identify randomized controlled trials (RCTs) comparing the efficacy of CBT with other treatment approaches in adults with confirmed knee/hip osteoarthritis. The pain intensity (primary outcome) and the secondary outcomes including insomnia severity, sleep efficiency, physical function as well as the severity of depression and fatigue were assessed at two time points (i.e., immediately after treatment and during the follow-up period). The effect size is expressed as standardized mean difference (SMD) with SMDs of < 0.2, 0.2–0.5, and 0.5–0.8, and > 0.8 representing negligible, small, medium, and large effect sizes, respectively.ResultsFifteen RCTs were included for analysis. Immediately after CBT intervention, meta-analysis showed similar treatment effect in pain severity [SMD = –0.46, 95% confidence interval (CI): –0.95 to 0.04, 11 studies, 1557 participants] and other symptoms including depression (SMD = –0.26, 95% CI: –0.58 to 0.06, five studies, 735 participants), fatigue (SMD = –2.44, 95% CI:–6.53 to 1.65, two RCTs, 511 participants), and physical function (SMD = –0.11, 95% CI:–0.25 to 0.02, five RCTs, 720 participants) between CBT and control groups, while there was an improvement in insomnia severity (SMD = –0.65, 95% CI: –1.06 to –0.24, four RCTs, 639 participants, medium treatment effect) and sleep efficiency (SMD = 0.32, 95% CI: 0.04 to 0.59, three RCTs, 352 patients, small treatment effect). During follow-up, CBT improved pain severity (SMD = –0.52, 95% CI: –1.03 to –0.01, eight studies, 1447 participants, medium treatment effect), insomnia (SMD = –0.43, 95% CI: –0.85 to –0.01, three RCTs, 571 participants, small treatment effect), and depression (SMD = –0.39, 95% CI: –0.59 to –0.18, four RCTs, 791 participants, small treatment effect). Nevertheless, sleep efficiency, fatigue, and physical function were not improved in the follow-up period.ConclusionOur results may suggest the durability of CBT-associated treatment benefits, supporting its role as a potential promising alternative or complementary intervention for patients with knee/hip osteoarthritis, especially against pain and insomnia. Future large-scale investigations are warranted to verify our findings.Systematic review registration[https://www.crd.york.ac.uk/prospero/], identifier [CRD42022331165]

    Corrigendum to “Nutrient supply in the Southern East China Sea after Typhoon Morakot”

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    Author Posting. © Sears Foundation for Marine Research, 2013. This article is posted here by permission of Sears Foundation for Marine Research for personal use, not for redistribution. The definitive version was published in Journal of Marine Research 71 (2013): 451-452, doi:10.1357/002224013812587609

    Nutrient supply in the Southern East China Sea after Typhoon Morakot

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    Author Posting. © Sears Foundation for Marine Research, 2013. This article is posted here by permission of Sears Foundation for Marine Research for personal use, not for redistribution. The definitive version was published in Journal of Marine Research 71 (2013): 133-149, doi:10.1357/002224013807343425.Recent studies show that typhoons have profound effects on phytoplankton assemblages along their tracks, but it is difficult to quantitatively estimate nutrient supply after a typhoon's passage due to a lack of nutrient information before and after the arrival of a typhoon. During the passage of Typhoon Morakot (July 22 to Aug. 26, 2009), we conducted pre- and post-typhoon field cruises to study nutrient supply in the Southern East China Sea (SECS). The results showed nitrate and phosphate supplies to the water column in the SECS after the typhoon's passage were 5.6 × 1011 g-N/day and 7.8 × 1010 g-P/day which were significantly higher than those before the typhoon occurred (nitrate supply = 1 × 109 g-N/day, phosphate supply = 1.6 × 108 g-P/day). We conclude from this data, and after consulting the available physical data, that the highest nitrate concentration was caused by strong upwelling and/or vertical mixing, and input of nutrient-replete terrestrial waters. The nitrate and phosphate input related to the passage of Typhoon Morakot can account for approximately 86% and 87% of summer nitrate and phosphate supplies to the southern East China Sea.This research was supported by the Top University Program and the National Science Council (NSC101-2116M-110- 001, NSC101-2611-M-110-015-MY3, NSC100-2119-M-110-003, NSC98-2611-M-019-014-MY3, NSC NSC98-2611-M-002-019-MY3) of Taiwan to C.-C. Hung, G.-C.Gong and S. Jan

    Construction and characterization of an expressed sequenced tag library for the mosquito vector Armigeres subalbatus

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    <p>Abstract</p> <p>Background</p> <p>The mosquito, <it>Armigeres subalbatus</it>, mounts a distinctively robust innate immune response when infected with the nematode <it>Brugia malayi</it>, a causative agent of lymphatic filariasis. In order to mine the transcriptome for new insight into the cascade of events that takes place in response to infection in this mosquito, 6 cDNA libraries were generated from tissues of adult female mosquitoes subjected to immune-response activation treatments that lead to well-characterized responses, and from aging, naïve mosquitoes. Expressed sequence tags (ESTs) from each library were produced, annotated, and subjected to comparative analyses.</p> <p>Results</p> <p>Six libraries were constructed and used to generate 44,940 expressed sequence tags, of which 38,079 passed quality filters to be included in the annotation project and subsequent analyses. All of these sequences were collapsed into clusters resulting in 8,020 unique sequence clusters or singletons. EST clusters were annotated and curated manually within ASAP (A Systematic Annotation Package for Community Analysis of Genomes) web portal according to BLAST results from comparisons to Genbank, and the <it>Anopheles gambiae </it>and <it>Drosophila melanogaster </it>genome projects.</p> <p>Conclusion</p> <p>The resulting dataset is the first of its kind for this mosquito vector and provides a basis for future studies of mosquito vectors regarding the cascade of events that occurs in response to infection, and thereby providing insight into vector competence and innate immunity.</p

    Clinical characteristics and therapeutic outcomes of nosocomial super-infection in adult bacterial meningitis

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    <p>Abstract</p> <p>Background</p> <p>Super-infection in adult bacterial meningitis (ABM) is a condition wherein the cerebrospinal fluid (CSF) grows new pathogen(s) during the therapeutic course of meningitis. It is an uncommon but clinically important condition rarely examined in literature.</p> <p>Methods</p> <p>Twenty-seven episodes of super-infection states in 21 ABM patients collected in a 9.5-year study period (January 2001 to June 2010) were evaluated. The clinical characteristics, implicated pathogens, results of antimicrobial susceptibility tests, and therapeutic outcomes were analyzed.</p> <p>Results</p> <p>Twenty-one patients (13 men, 8 women) aged 25-73 years (median, 45 years) had post-neurosurgical state as the preceding event and nosocomial infection. The post-neurosurgical states included spontaneous intracranial hemorrhage (ICH) with craniectomy or craniotomy with extra-ventricular drainage (EVD) or ventriculo-peritoneal shunt (VPS) in 10 patients, traumatic ICH with craniectomy or craniotomy with EVD or VPS in 6 patients, hydrocephalus s/p VPS in 2 patients, and one patient each with cerebral infarct s/p craniectomy with EVD, meningeal metastasis s/p Omaya implant, and head injury. All 21 patients had EVD and/or VP shunt and/or Omaya implant during the whole course of ABM. Recurrent fever was the most common presentation and the implicated bacterial pathogens were protean, many of which were antibiotic resistant. Most patients required adjustment of antibiotics after the pathogens were identified but even with antimicrobial therapy, 33.3% (7/21) died. Morbidity was also high among survivors.</p> <p>Conclusions</p> <p>Super-infection in ABM is usually seen in patients with preceding neurosurgical event, especially insertion of an external drainage device. Repeat CSF culture is mandatory for diagnostic confirmation because most of the implicated bacterial strains are non-susceptible to common antibiotics used. Unusual pathogens like anaerobic bacteria and fungi may also appear. Despite antimicrobial therapy, prognosis remains poor.</p

    Clinical characteristics and prognosis of acute bacterial meningitis in elderly patients over 65: a hospital-based study

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    <p>Abstract</p> <p>Background</p> <p>To examine the clinical characteristics of bacterial meningitis in elderly patients.</p> <p>Methods</p> <p>261 patients with adult bacterial meningitis (ABM), collected during a study period of 11 years (2000-2010), were included for study. Among them, 87 patients aged ≥ 65 years and were classified as the elderly group. The clinical and laboratory characteristics and prognostic factors were analyzed, and a clinical comparison with those of non-elderly ABM patients was also made.</p> <p>Results</p> <p>The 87 elderly ABM patients were composed of 53 males and 34 females, aged 65-87 years old (median = 71 years). Diabetes mellitus (DM) was the most common underlying condition (34%), followed by end stage renal disease (7%), alcoholism (4%) and malignancies (4%). Fever was the most common clinical manifestation (86%), followed by altered consciousness (62%), leukocytosis (53%), hydrocephalus (38%), seizure (30%), bacteremia (21%) and shock (11%). Thirty-nine of these 87 elderly ABM patients had spontaneous infection, while the other 48 had post-neurosurgical infection. Forty-four patients contracted ABM in a community-acquired state, while the other 43, a nosocomial state. The therapeutic results of the 87 elderly ABM patients were that 34 patients expired and 53 patients survived. The comparative results of the clinical and laboratory characteristics between the elderly and non-elderly ABM patients showed that only peripheral blood leukocytosis was significant. Presence of shock and seizure were significant prognostic factors of elderly ABM patients.</p> <p>Conclusions</p> <p>Elderly ABM patients accounted for 34.8% of the overall ABM cases, and this relatively high incidence rate may signify the future burden of ABM in the elderly population in Taiwan. The relative frequency of implicated pathogens of elderly ABM is similar to that of non-elderly ABM. Compared with non-elderly patients, the elderly ABM patients have a significantly lower incidence of peripheral blood leukocytosis. The mortality rate of elderly ABM remains high, and the presence of shock and seizures are important prognostic factors.</p
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