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Objective: To evaluate for disparities in peripartum toxicology testing among maternal-infant dyads across a hospital network and subsequent child protective services (CPS) involvement., Methods: Retrospective chart review of 59,425 deliveries at 5 hospitals in Massachusetts between 2016 and 2020. We evaluated associations between maternal characteristics, toxicology testing, and child welfare involvement with disproportionality risk ratios and hierarchical logistical regression., Results: Toxicology testing was performed on 1959 (3.3%) dyads. Younger individuals and individuals of color were more likely to be tested for cannabis use or maternal medical complications compared to white non-Hispanic individuals. Among those without a substance use disorder, age <25 (adjusted odds ratio [aOR] 2.81; 95% confidence interval [CI], 2.43-3.26), race and ethnicity (non-Hispanic Black (aOR 1.80; 95% CI, 1.52-2.13), Hispanic (aOR 1.23; 95% CI, 1.05-1.45), mixed race/other (aOR 1.40; 95% CI, 1.04, 1.87), unavailable race (aOR 1.92; 95% CI, 1.32-2.79), and public insurance (Medicaid [aOR 2.61; 95% CI, 2.27-3.00], Medicare [aOR 13.76; 95% CI, 9.99-18.91]) had increased odds of toxicology testing compared to older, white non-Hispanic, and privately insured individuals. The disproportionality ratios in testing were greater than 1.0 for individuals under 25 years old (3.8), Hispanic individuals (1.6), non-Hispanic Black individuals (1.8), individuals of other race (1.2), unavailable race (1.8), and individuals with public insurance (Medicaid 2.6; Medicare 10.6). Among dyads tested, race and ethnicity was not associated with CPS involvement., Conclusions: Peripartum toxicology testing is disproportionately performed on non-white, younger, and poorer individuals and their infants, with cannabis use and medical complications prompting testing more often for patients of color than for white non-Hispanic individuals., (Copyright © 2023 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.)

Recently, numerous organic pollutants have been detected in water environment. The safety of our drinking water has attracted widespread attention. Effective methods to screen and identify high-concern substances are urgently needed. In this study, the combined workflow for the detection and identification of high-concern organic chemicals was established and applied to tap water samples from the Yangtze River Basin. The solid phase extraction (SPE) sorbents were compared and evaluated and finally the HLB cartridge was selected as the best one for most of the contaminants. Based on target, suspect and non-target analysis, 3023 chemicals/peaks were detected. Thirteen substances such as diundecyl phthalate (DUP), 2-hydroxyatrazine, dioxoaminopyrine and diethyl-2-phenylacetamide were detected in drinking water in the Yangtze River Basin for the very first time. Based on three kinds of prioritization principles, 49 ubiquitous, 103 characteristic chemicals and 13 inefficiently removed chemicals were selected as high-concern substances. Among them, 8, 31, 9, 3, 4 substances overlapped with the toxic, risky or high-concern chemicals lists in China, America, European Union, Japan, Korea, respectively. Specific management and removal strategies were further recommended. The workflow is efficient for identification of key pollutants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Background: The need for multidisciplinary care of patients with advanced limb threat is well established. We examined patient reported outcomes and health-related quality of life (HR-QoL) for those who completed a multidisciplinary extremity preservation program (EPP) at our institution., Methods: Patients with advanced limb threat, who had previously failed standard management at a tertiary-care center, were referred to EPP for evaluation by a multidisciplinary panel of vascular, plastic, orthopedic and podiatric surgeons, along with infectious disease, prosthetics, orthotics, imaging, palliative care, social work and wound nursing specialists. HR-QoL was quantified before and after EPP participation with the RAND-36 questionnaire. The validated RAND-36 assesses physical function, role limitations caused by physical and emotional health problems, social functioning, emotional well-being, energy, pain and general health perceptions., Results: From 2018 to 2020, 185 patients were referred to EPP. After review by the multidisciplinary panel, 120 were accepted into the program, 63 of whom completed their course of care; 9 were one-time consultations. The median number of EPP in-person care visits was 23 (13-54) per participant; 87.3% of patients received one or more surgical procedure, including operative debridement (73%), revascularization (44%), soft-tissue reconstruction or transplantation (46%), as well as hyperbaric oxygen therapy (11%) during their course of treatment. 85.7% of patients achieved complete wound healing, 41.5% occurring within 6 months. Ultimately, 14.3% required a major amputation. Graduates noted improvement in all categories of the HR-QoL upon completion, including those undergoing major amputation. On adjusted multivariate regression analysis, patients with immunocompromised status were more likely to show greater improvement in their social function (OR: 10.1; P < 0.044) and emotional role limitation (OR: 8.1; P = 0.042), while, patients with larger wound volume at presentation were more likely to have greater improvement in their general health (OR: 1.1; P < 0.049). Conversely, patients with a smoking history had less improvement in energy level (OR: 0.4; P = 0.044) and patients with dialysis-dependence had less improvement in social function (OR: 0.2; P = 0.034)., Conclusions: Coordinated, multidisciplinary extremity preservation program improves HR-QoL of patients with complex limb threat, including those who are immunocompromised with impaired social function and emotional role limitations. Furthermore, study is warranted to better characterize the generalizability of this approach, including considerations of cost-effectiveness, wound recidivism, and limiting the number of in-person visits required to achieve complete healing., (Copyright © 2022 Elsevier Inc. All rights reserved.)

With the development of Chinese economy, more and more attention has been paid to environmental protection, the implementation of water price policy affects economic and environmental changes in China. This paper analyzes the impact of water price policy on agricultural land use and the scale of water pollution discharge in 240 cities in China between 2001 and 2017, by including data from China Urban Statistical Yearbook and China Land & Resources Almanac. The theoretical analysis of this study indicates that the optimal scale of pollution depends on the local initial endowment, economic investment capital and the marginal cost of environmental pollution caused by government's economic activities. Furtherly, the economic activities have a worsening impact on environmental pollution, but when the government implements environmental protection and water price policy measures in response to environmental pollution caused by economic activities, it has a significant impact on the decline in the scale of pollution. The government has promoted the pollution suppression model in the formulation of water prices, which has internalized the external cost of pollution in economic activities and can effectively reduce the scale of agricultural water pollution discharge., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2020 Elsevier B.V. All rights reserved.)

The adsorption of phosphate on hydrated ferric oxide (HFO) was studied in solutions containing major seawater ions (Na + , Mg 2+ , Cl - , SO 4 2- , Ca 2+ , K + ) at pHs 6.5, 7.5 and 8.5. The presence of these ions promotes phosphate adsorption and the process is electrostatic in nature. Despite this electrostatic force, the precipitation of hydroxyapatite in the presence of Ca 2+ at pH 8.5 also plays an important role in the removal of phosphates from the dissolved phase. Energy dispersive X-ray spectroscopy (EDS) and Fourier transform infrared (FTIR) spectra support that phosphate adsorption on HFO surface can be attributed to inner sphere complexes with the formation of bidentate complexes (FeO) 2 PO 2 in the presence of main seawater ions at pH = 8.5. The results of EDS clearly indicated that Fe-P-Ca complexes, Fe-P-Mg, or other phosphate-bridged ternary complexes were not formed during adsorption in the presence of NaCl, KCl, CaCl 2 , Na 2 SO 4 and MgCl 2 . This observation differs somewhat from that the typical explanation used to describe the phosphate adsorption mechanism on HFO. The CD-MUSIC model makes it possible to describe this adsorption mechanism of phosphate on HFO in the presence of 0.7 M NaCl, and these outcomes are coherent with the experimental FTIR and EDS results., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: The effect of syndesmotic fixation on restoration of pressure mechanics in the setting of a syndesmotic injury is largely unknown. The purpose of this study is to examine the contact mechanics of the tibiotalar joint following syndesmosis fixation with screws versus a flexible fixation device for complete syndesmotic injury., Methods: Six matched pairs of cadaveric below knee specimens were dissected and motion capture trackers were fixed to the tibia, fibula, and talus and a pressure sensor was placed in the tibiotalar joint. Each specimen was first tested intact with axial compressive load followed by external rotation while maintaining axial compression. Next, syndesmotic ligaments were sectioned and randomly assigned to repair with either two TightRopes® or two 3.5 mm cortical screws and the protocol was repeated. Mean contact pressure, peak pressure, reduction in contact area, translation of the center of pressure, and relative talar and fibular motion were calculated. Specimens were then cyclically loaded in external rotation and surviving specimens were loaded in external rotation to failure., Results: No differences in pressure measurements were observed between the intact and instrumented states during axial load. Mean contact presure relative to intact testing was increased in the screw group at 5 Nm and 7.5 Nm torque. Likewise, peak pressure was increased in the TightRope group at 7.5 Nm torque. There was no change in center of pressure in the TightRope group at any threshold; however, at every threshold tested there was significant medial and anterior translation in the screw group relative to the intact state., Conclusion: Either screws or TightRope fixation is adequate with AL alone. With lower amounts of torque, the TightRope group appears to have contact and pressure mechanics that more closely match native mechanics., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Question: What health information needs are perceived by people with low back pain?, Design: Systematic review of publications examining perceived health information needs related to low back pain identified through Medline, EMBASE, CINAHL and PsycINFO (1990 to 2018)., Participants: Adults with low back pain of any duration., Data Extraction and Analysis: Two reviewers independently extracted descriptive data regarding study design and methodology, and assessed risk of bias. Aggregated findings of the perceived needs of people with low back pain regarding health information were meta-synthesised., Results: Forty-one studies (34 qualitative, four quantitative and three mixed-methods) were identified. Two major areas of perceived health information needs for low back pain emerged. The first major area was needs related to information content: general information related to low back pain, its cause and underlying pathology; strong desire for diagnosis and imaging; prognosis, future disability and effect on work capacity; precipitants and management of flares; general management approaches; self-management strategies; prevention; and support services. The second major area of needs related to how the information was delivered. People with low back pain wanted clear, consistent information delivered in suitable tone and understandable language., Conclusion: Available data suggest that the information needs of people with low back pain are centred around their desire for a diagnosis, potentially contributing to expectations for and overuse of imaging. People with low back pain expressed a strong desire for clear, consistent and personalised information on prognosis, treatment options and self-management strategies, related to healthcare and occupational issues. To correct unhelpful beliefs and optimise delivery of evidence-based therapy, patient and healthcare professional education (potentially by an integrated public health approach) may be warranted., (Copyright © 2019 Australian Physiotherapy Association. Published by Elsevier B.V. All rights reserved.)

Introduction: In this study, we examined the effect of mineral trioxide aggregate (MTA) on macrophage polarization and the potential involvement of Axl/nuclear factor kappa B (NF-κB) signaling in mediating the effect of MTA., Methods: The human monocyte cell line THP-1 was cultured with MTA solution for 1, 2, or 3 days, and the population change of M2 macrophages was analyzed by flow cytometry. Expression of M2 cytokines was examined by enzyme-linked immunosorbent assay. Phagocytosis and angiogenesis-induction ability were also assayed. The involvement of Axl/NF-κB signaling in MTA-treated cells was examined by analyzing phosphorylation status of Axl, Akt, IKKα/β, and IκBα. Specific inhibitors for Axl/Akt/NF-κB signaling were added to MTA-treated THP-1 cells, and their cytokine expression change was examined., Results: Flow cytometry analysis showed that MTA treatment increased CD206＋ cells in a time-dependent way. After MTA treatment, the expression of M2-related cytokines was up-regulated. MTA also enhanced phagocytic ability and the ability of THP-1 cells to induce angiogenesis. Treatment of MTA led to activate Axl/Akt/NF-kB signal axis by phosphorylation of Axl, Akt, IKKα/β, IκBα, and p65. In addition, MTA-induced interleukin 10, transforming growth factor beta, and vascular endothelial growth factor expression was suppressed as specific inhibitors were added., Conclusions: Our findings indicate that MTA is able to induce macrophage polarization toward the M2 phenotype, with up-regulation of interleukin 10, transforming growth factor beta, and vascular endothelial growth factor, and that Axl/Akt/NF-κB signaling participates in this process. These results provide the cellular and molecular basis of MTA's anti-inflammatory action in clinical applications., (Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Question: What needs of non-biomedical services are perceived by people with low back pain?, Design: Systematic review of qualitative and quantitative studies examining perceived needs of non-biomedical services for low back pain, identified through searching of MEDLINE, EMBASE, CINAHL and PsycINFO (1990 to 2016)., Participants: Adults with low back pain of any duration., Data Extraction and Analysis: Descriptive data regarding study design and methodology were extracted. The preferences, expectations and satisfaction with non-biomedical services reported by people with low back pain were identified and categorised within areas of perceived need., Results: Twenty studies (19 qualitative and one quantitative) involving 522 unique participants (total pool of 590) were included in this systematic review. Four areas emerged. Workplace: people with low back pain experience pressure to return to work despite difficulties with the demands of their occupation. They want their employers to be informed about low back pain and they desire workplace accommodations. Financial: people with low back pain want financial support, but have concerns about the inefficiencies of compensation systems and the stigma associated with financial remuneration. Social: people with low back pain report feeling disconnected from social networks and want back-specific social support. Household: people with low back pain report difficulties with household duties; however, there are few data regarding their need for auxiliary devices and domestic help., Conclusion: People with low back pain identified work place, financial and social pressures, and difficulties with household duties as areas of need beyond their healthcare requirements that affect their ability to comply with management of their condition. Consideration of such needs may inform physiotherapists, the wider health system, social networks and the workplace to provide more relevant and effective services. [Chou L, Cicuttini FM, Urquhart DM, Anthony SN, Sullivan K, Seneviwickrama M, Briggs AM, Wluka AE (2018) People with low back pain perceive needs for non-biomedical services in workplace, financial, social and household domains: a systematic review. Journal of Physiotherapy 64: 74-83]., (Copyright © 2018 Australian Physiotherapy Association. Published by Elsevier B.V. All rights reserved.)

Listeria monocytogenes, causative agent of human listeriosis, has been isolated from a wide variety of foods including deli meats, soft cheeses, cantaloupes, sprouts and canned mushrooms. Standard control measures for restricting microbial growth such as refrigeration and high salt are often inadequate as L. monocytogenes grows quite well in these environments. In an effort to better understand the genetic and physiological basis by which L. monocytogenes circumvents these controls, a transposon library of L. monocytogenes was screened for changes in their ability to grow in 7% NaCl and/ or at 5 °C. This work identified a transposon insertion upstream of an operon, here named lstABC, that led to a reduction in growth in 7% NaCl. In-frame deletion studies identified lstC which codes for a GNAT-acetyltransferase being responsible for the phenotype. Transcriptomic and RT-PCR analyses identified nine genes that were upregulated in the presence of high salt in the ΔlstC mutant. Further analysis of lstC and the genes affected by ΔlstC is needed to understand LstC's role in salt tolerance., (Published by Elsevier Ltd.)

A total of 24 stranded or bycatch cetaceans, including Balaenoptera omurai, Lagenodelphis hosei, Kogia sima, Stenella attenuata, Grampus griseus, Neophocaena phocaenoides, and Sousa chinensis, were collected from 2001 to 2011 in Taiwan. Using the muscular δ(13)C and δ(15)N data, three ecological groups were identified as the oceanic baleen whale, the neritic, and the coastal toothed whale groups, coinciding with their taxonomy, feeding habits and geographical distribution. A horizontal inshore to offshore distribution was found for the sympatric neritic toothed dolphins, G. griseus, K. sima, S. attenuata, and L. hosei in the outermost offshore waters, accompanying their growth. For the first time we identify Taiwan's Chinese white dolphin, S. chinensis, as an exclusive fish eater. Cd and As bioaccumulated in the G. griseus, L. hosei and S. attenuata increase as they grow. Prey-derived As- and Cd-induced health threats were found in L. hosei, and G. griseus., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Predicting metal concentrations in surface waters is an important step in the understanding and ultimately the assessment of the ecological risk associated with metal contamination. In terms of risk an essential piece of information is the accurate knowledge of the partitioning of the metals between the dissolved and particulate phases, as the former species are generally regarded as the most bioavailable and thus harmful form. As a first step towards the understanding and prediction of metal speciation in the Scheldt Estuary (Belgium, the Netherlands), we carried out a detailed analysis of a historical dataset covering the period 1982-2011. This study reports on the results for two selected metals: Cu and Cd. Data analysis revealed that both the total metal concentration and the metal partitioning coefficient (Kd) could be predicted using relatively simple empirical functions of environmental variables such as salinity and suspended particulate matter concentration (SPM). The validity of these functions has been assessed by their application to salinity and SPM fields simulated by the hydro-environmental model SLIM. The high-resolution total and dissolved metal concentrations reconstructed using this approach, compared surprisingly well with an independent set of validation measurements. These first results from the combined mechanistic-empirical model approach suggest that it may be an interesting tool for risk assessment studies, e.g. to help identify conditions associated with elevated (dissolved) metal concentrations., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A simple and effective route for the production of 5-hydroxymethyl furfural (HMF) and furfural from microcrystalline cellulose (MCC) has been developed. CoSO(4) in an ionic liquid, 1-(4-sulfonic acid) butyl-3-methylimidazolium hydrogen sulfate (IL-1), was found to be an efficient catalyst for the hydrolysis of cellulose at 150°C, which led to 84% conversion of MCC after 300min reaction time. In the presence of a catalytic amount of CoSO(4), the yields of HMF and furfural were up to 24% and 17%, respectively; a small amount of levulinic acid (LA) and reducing sugars (8% and 4%, respectively) were also generated. Dimers of furan compounds were detected as the main by-products through HPLC-MS, and with the help of mass spectrometric analysis, the components of gas products were methane, ethane, CO, CO(2,) and H(2). A mechanism for the CoSO(4)-IL-1 hydrolysis system was proposed and IL-1 was recycled for the first time, which exhibited favorable catalytic activity over five repeated runs. This catalytic system may be valuable to facilitate energy-efficient and cost-effective conversion of biomass into biofuels and platform chemicals., (2010. Published by Elsevier Ltd. All rights reserved.)

A novel analytical technique for isotopic analysis of dissolved and particulate iron (Fe) from various marine environments is presented in this paper. It combines coprecipitation of dissolved Fe (DFe) samples with Mg(OH)(2), and acid digestion of particulate Fe (PFe) samples with double pass chromatographic separation. Isotopic data were obtained using a Nu Plasma MC-ICP-MS in dry plasma mode, applying a combination of standard-sample bracketing and external normalization by Cu doping. Argon interferences were determined prior to each analysis and automatically subtracted during analysis. Sample size can be varied between 200 and 600 ng of Fe per measurement and total procedural blanks are better than 10 ng of Fe. Typical external precision of replicate analyses (1S.D.) is +/-0.07 per thousand on delta(56)Fe and +/-0.09 per thousand on delta(57)Fe while typical internal precision of a measurement (1S.E.) is +/-0.03 per thousand on delta(56)Fe and +/-0.04 per thousand on delta(57)Fe. Accuracy and precision were assured by the analysis of reference material IRMM-014, an in-house pure Fe standard, an in-house rock standard, as well as by inter-laboratory comparison using a hematite standard from ETH (Zürich). The lowest amount of Fe (200 ng) at which a reliable isotopic measurement could still be performed corresponds to a DFe or PFe concentration of approximately 2 nmol L(-1) for a 2 L sample size. To show the versatility of the method, results are presented from contrasting environments characterized by a wide range of Fe concentrations as well as varying salt content: the Scheldt estuary, the North Sea, and Antarctic pack ice. The range of DFe and PFe concentrations encountered in this investigation falls between 2 and 2000 nmol L(-1) Fe. The distinct isotopic compositions detected in these environments cover the whole range reported in previous studies of natural Fe isotopic fractionation in the marine environment, i.e. delta(56)Fe varies between -3.5 per thousand and +1.5 per thousand. The largest fractionations were observed in environments characterized by redox changes and/or strong Fe cycling. This demonstrates the potential use of Fe isotopes as a tool to trace marine biogeochemical processes involving Fe.

The study was designed to explore the psychosocial effects on caretakers of children in Taiwan on chronic peritoneal dialysis (CPD). This is a case-control study, performed with subjects drawn from eight medical centers. The study group consisted of caretakers of 32 children with renal failure being treated with CPD. For comparison, a control group of caretakers of 64 healthy children as well as the regional Taiwanese studies were used. Two instruments were used to explore the presence of probable depression and quality of life (QOL) of the caretakers: the Taiwanese Depression Questionnaire, and the World Health Organization QOL BRIEF-Taiwan Version. In the study group, only 25% of caregivers had full-time jobs, and 66% of families had an annual income of less than US dollar 15,000. Of the 32 families in the study group, 16% had only a single parent. The prevalence of probable depression was significantly more common in the study group compared with control and referent group (28% vs 5% and 9.44%; P = 0.001). QOL scores in four domains were also significantly lower in the study group. In conclusion, even with the advances of peritoneal dialysis techniques, caring for children on CPD in Taiwan has significant adverse psychosocial effects on the primary caregivers. Attention should be paid to the psycho-social status of the caregivers.

Past and on-going reclamation, dredging, construction and shipping activities impact Ponggol Estuary, located on the northeastern coast of Singapore. Tin, lead, nickel, cadmium, and copper in particulate and dissolved fractions and sediments ranged from ND (undetectable)-92 ppm, ND-303.2 ppm, ND-2818.4 ppm, ND-74.4 ppm and ND-1117.7 ppm, respectively. Intensive dredging activity during the monitoring period may have led to the resuspension and bioavailability of particulate metals. This was tested by the exposure of phytoplankton and bacteria in mesocosms to previously measured environmental levels of heavy metals and the contaminated sediments with the highest heavy metal concentrations from one of the impacted sites. The results showed significant copper toxicity to phytoplankton and autotrophic bacteria, followed by nickel and lead at all concentrations tested. Enhanced rates of heterotrophic bacterial production and total bacterial abundance were observed in treatments with higher metal concentrations. Among the various treatments, particulate and sediment metal concentrations were significantly different from those of the control. Mesocosms using contaminated sediments with the highest metal concentrations compared with the control showed a bioavailability of metals that resulted in the inhibition of phytoplankton and autotrophic bacteria. High concentrations of copper (5.52-11.35 mg L(-1)) and nickel (2.42-2.71 mg L(-1)) observed in the aqueous phase of treatment mesocosms, and attributed to release from the contaminated sediments could account for the toxicity to phytoplankton and autotrophic bacteria.

To date, there has been very little research into the possible effects of endodontic therapy on regeneration of a lost periodontal attachment. The objective of this study was to examine the effects of the endodontic medication, camphorated parachlorophenol (CMCP), on human periodontal ligament cells in vitro. The cytotoxic effects of CMCP were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide colorimetric assay and cell proliferation using a [3H]thymidine incorporation assay. CMCP inhibited the human periodontal ligament cells viability and proliferation in a dose-dependent manner (p < 0.05). These data indicate that the use of CMCP in a root canal could cause periodontium damage. Although this study was conducted in vitro, the findings suggest that it may not be advisable to use CMCP as an interim medication when a periodontal surgical procedure, especially an attempt at regeneration or a new attachment procedure, is being considered in tissues adjacent to the endodontically involved tooth.

An intracanal medicine is often required because microorganisms in the dentinal tubes may be difficult to eliminate completely by instrumentation. Phenolic compounds are widely used in dental treatment as sedatives for the dental pulp or as disinfectants for caries and the root canal. In this study, propidium iodide fluorescence and DNA precipitation assay were used to investigated the cytotoxic and genotoxic effects of camphorated phenol and camphorated parachlorophenol on cultured human pulp fibroblasts in vitro. Both medicines reduced the content of double-stranded polynucleic acid of fibroblasts over a 24-h culture period in a concentration-dependent manner. Camphorated parachlorophenol was more cytotoxic than camphorated phenol. But, both medicines did not cause genotoxicity on pulp cells. The advantage of these experimental methods are simplicity and rapidity. Furthermore, this experimental system may be useful for preliminary cytotoxicity and genotoxicity screening of various dental medicines in vitro.

The antitumour antibiotic pingyangmycin (PYM; bleomycin A5) was isolated from many components of bleomycin (BLM) produced by Streptomyces pingyangensisn. PYM has a similar chemical structure to that of BLM but the terminal amine moiety is different. Therefore, it would be of significance to demonstrate the antitumour effect and action mechanism of PYM on cultivated tumour cells. In this study, we used the cell growth curve, plating efficiency, and DNA synthesis inhibition assay to demonstrate the cytotoxicity of PYM on cultured KB cells. In the meantime, the morphological variations of drug-treated cells were also observed. In addition, we used the DNA precipitation assay, a simple and rapid assay, for detecting DNA damage caused by PYM on cultured KB cells for potential genotoxicity. Our results indicate that the effect of PYM significantly inhibits the cell growth, colonyforming ability, and DNA synthesis of KB cells in a dose-dependent manner. Furthermore, when treated with 5 micrograms/ml of PYM for 24 h on cultured KB cells, DNA strand breaks can be induced (P < 0.05). Therefore, it is considered that the action mechanism of PYM is due to its ability to inhibit the synthesis of DNA and split the DNA chains.

Recent concerns have been raised about the possibility that estrogenic chemicals, in particular bisphenol-A, or BPA, might be leached out of dental sealants. This study aimed to identify and quantify BPA and other components released from seven light-cured fissure sealants in vitro. None of the tested sealants was shown to have released BPA; however, the investigators identified other eluted components that should be investigated for their biological effects.

Radiographs of phantoms were produced using E-speed film and various rare earth X-ray beam filters. The rare earth filters considerably reduced the amount of radiation needed to produce diagnostic quality images and, in many cases, improved image quality. These filters can be implemented easily and inexpensively in a clinical setting, resulting in radiation exposure reductions of up to 71%.

Studies were performed to determine the mechanism by which the antihypertensive agent clonidine increases urine flow (V). In 11 anesthetized, hydropenic dogs, i.v. administration of clonidine (30 mug/kg) increased arterial pressure from 128 +/- 4 to 142 +/- 3 mm Hg and slowed heart rate from 138 +/- 7 to 95 +/- 7 beats/min within 30 min of injection; blood pressure then fell to 121 +/- 5 mm Hg 30 to 60 min after injection, and 112 +/- 5 mm Hg in the next 30-min period. V increased from 0.36 +/- 0.09 to 0.93 +/- 0.13 Uosm ml/min and urine osmolality (Uopsm) decreased from 1378 +/- 140 to 488 +/- 82 mOsm/kg of H2O 30 to 60 min following injection (P less than 0.001). These changes were accompanied by a decrease in TcH20. This increased V was not associated with increased glomerular filtration rate (GFR) or solute excretion, and occurred in acutely denervated kidneys and kidneys protected from the initial increase in arterial pressure by constriction of a suprarenal aortic clamp. By contrast, V TcH2O and UOsm were not altered by clonidine administration in seven acutely hypophysectomized dogs receiving a constant infusion of antidiuretic hormone (ADH) (80 muU/kg/min), despite similar hemodynamic changes produced by the drug. The results suggest that clonidine increases V through inhibition of ADH release, possibly via an indirect pathway mediated by the drug's alpha-adrenergic on the circulation.