Computer simulation of the structural properties of fatty-acid modified PAMAM dendrimers at pH 5 and 7

In this work, we performed coarse-grained molecular dynamics (CGMD) simulations of G3, G4, and G5 polyamidoamine (PAMAM) dendrimers grafting with fatty acid (FTA) chains. The FTA chains of varying length and grafting densities (50% and 100% of surface terminals) correspond to pH 7 and 5, respectively. Our findings suggested that the structural properties of dendrimers were determined by dendrimer generation, polymerization degrees, and pH. With one exception, the size of the FTA grafting dendrimer shrank after fatty acid attachment. Because of the protonation of the dendrimer's interior amines at low pH, the FTA chains are distributed at the dendrimer's surface group. At pH 7, the FTA chains that have aggregated in the interior of the dendrimer cause chain crowding. Our research provided references on drug encapsulation and the lower toxicity of these hydrophobically modified nanoparticles.

Role of humic substances and alkaline in phosphorus release from sludge pre-treated by (alkali-) hydrothermal

The scarcity of phosphorus (P) resources makes the recovery of P urgent. Sludge is a secondary resource rich in P, and the release of P from it is a key step for recovery. Hydrothermal (HT) is currently a popular method for sludge pretreatment, and its combination with alkaline (alkali-hydrothermal, AHT) could reduce the energy consumption in treatment. This study tried to compare their P release profiles in treating activated sludge in which organic P (OP) and non-apatite inorganic P (NAIP) were co-existence. Apart from the OP release in cell lysis, P release from NAIP brought by the joint effect of OH^- and humic substances (HS) formed in treatment was focused. The results showed that, compared to HT treatment, more P was released when OH^- participated (AHT), and the peak P release was observed at 160 °C. Variation of P distribution in the treated sludge revealed that more P was released from NAIP in AHT than in HT. HS formed in treatments was extracted and characterized. The amount and the structure of the HS varied significantly with the treatment conditions, and there was a linear correlation ship between PO₄^3--P release and the humic acid (HA) amount in HS. Mechanism study indicated there was a synergism between HS and OH^- in promoting PO₄^3--P release from NAIP. This study linked HS produced by sludge with P release, which provided a new perspective for subsequent P recovery from sludge.

Long-term Patterns of Failure and the Value of Blood Prognostic Markers in Anal Cancers Treated With Intensity-Modulated Radiation Therapy

BACKGROUND

To analyze the long-term outcomes and prognostic value of hematological parameters in anal cancer patients receiving intensity-modulated radiation therapy (IMRT).

MATERIALS

Hospital records of consecutive patients with anal squamous cell carcinoma who received curative-intent IMRT according to a standardized contouring protocol between 2010 and 2020 were reviewed. Locoregional failure-free survival (LRFS), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS) were estimated using the Kaplan-Meier method. Coverage of locoregional recurrences by the initial IMRT volumes were assessed. The prognostic value of pretreatment blood counts for PFS and OS were determined using Cox regression analysis.

RESULTS

A total of 166 patients were analyzed with a median follow-up of 3.3 years. Forty-six percent and 54% of patients had Stage I-II and IIIA-B cancers, respectively. The 5-year LRFS, DMFS, PFS and OS were 81%, 89%, 65% and 76% respectively. Grade ≥ 3 toxicity occurred in 5% of patients. Of all patients who relapsed, 70% had only locoregional recurrence as first site of failure. Ninety percent of locoregional recurrences were in-field. Hemoglobin, neutrophil and platelet counts were associated with PFS on univariable analysis, but only cancer stage and p16 status remained prognostic on multivariable analysis. Patients with more advanced cancer stages also had higher baseline neutrophil counts. Performance status and neutrophil counts were prognostic for OS on multivariable analysis.

CONCLUSION

This study affirms the long-term efficacy and safety of IMRT. Treatment resistance, rather than radiation geographic miss, is a major issue underpinning locoregional recurrences. Pretreatment blood counts were not validated to be independently prognostic for disease recurrence.

Association of serum homocysteine levels with the severity and calcification of coronary atherosclerotic plaques detected by coronary CT angiography

AIM

In this study, we aim to evaluate the association of risk factors including homocysteine (Hcy) with the severity and burden of coronary atherosclerotic plaques detected by computed tomography angiography (CTA).

METHODS

Six hundred fifty-nine subjects who underwent CTA for the assessment of coronary artery disease (CAD) were studied. All the subjects enrolled had no clinical cardiovascular disease symptoms. Logistic regression showed apart from age, hypertension, smoking, triglyceride, low-density lipoprotein (LDL) cholesterol, and total bilirubin, Hcy was an independently risk factor of the severity of coronary disease. And Hcy was also found an independent predictor for the presence of calcified plaque. When the participants were divided into 4 groups according to serum Hcy quartiles (Q1-Q4 groups), both the percentage of patients with >50% stenosis and the percentage of patients with calcified plaque were higher in Q4 compared to other groups. The OR of Hcy (>15 µmol/L) for >50% stenosis was 2.212 (95% CI=1.119 to 4.375, P=0.022) and the OR for Hcy (>15 µmol/L) for calcification was 1.668 (95% CI=1.030 to 2.699, P=0.037) respectively.

CONCLUSION

Our study shows Hcy is independently associated with both the severity and calcified plaque detected by CTA. Hcy may provide additional information about CAD in the subjects without clinical symptoms.

A meta-analysis of Chinese herbal medicines for vascular dementia

OBJECTIVE

To investigate the efficacy and safety of Chinese herbal medicines in the treatment of patients with vascular dementia.

DATA RETRIEVAL

We retrieved publications from Cochrane Library (2004 to July 2011), PubMed (1966 to July 2011), the Chinese Science and Technique Journals Database (1977 to July 2011), the China National Knowledge Infrastructure (1979 to July 2011), Google Scholar (July 2011), and the Chinese Biomedical Database (1977 to July 2011) using the key words "Chinese medicine OR Chinese herbal medicine" and "vascular dementia OR mild cognition impair OR multi-infarct dementia OR small-vessel dementia OR strategic infarct dementia OR hypoperfusion dementia OR hemorrhagic dementia OR hereditary vascular dementia".

SELECTION CRITERIA

Randomized controlled trials comparing Chinese herbal medicines with placebo/western medicine in the treatment of patients with vascular dementia were included. Diagnostic standards included Diagnostic and Statistical Manual of Mental Disorders-IV, and National Institute of Neurological Disorders and Stroke and Association Internationale pour la Recherché et l'Enseignement en Neurosciences. Two participants independently conducted literature screening, quality evaluation and data extraction. The quality of each trial was assessed according to the Cochrane Reviewers' Handbook 5.0.

MAIN OUTCOME MEASURES

Effective rate, Mini-Mental State Examination scores, Hasegawa Dementia Scale scores, and incidence of adverse reactions.

RESULTS

We identified 1 143 articles discussing the effects of Chinese medicine on vascular dementia. Thirty-one of these were included in the analysis. These studies involved a total of 2 868 participants (1 605 patients took Chinese medicine decoctions (treatment group); 1 263 patients took western medicine or placebo). The results of our meta-analysis revealed that Chinese herbal remedies in the treatment group were more efficacious than the control intervention (relative risk (RR) = 1.27; 95% confidence interval (CI): 1.18-1.38, P < 0.01). Mini-Mental State Examination scores were higher in patients taking Chinese herbal medicines than in those in the control group (weighted mean difference (WMD) = 2.83; 95%CI: 2.55-3.12, P < 0.01). Patients in the treatment group showed better disease amelioration than those in the control group (Hasegawa Dementia Scale scores; WMD = 2.41, 95%CI: 1.48-3.34, P < 0.01). There were also considerably fewer adverse reactions among those in the treatment group compared with those in the control group (RR = 0.20, 95%CI: 0.08-0.47, P < 0.01).

CONCLUSION

Chinese herbal medicine appears to be safer and more effective than control measures in the treatment of vascular dementia. However, the included trials were generally low in quality. More well-designed, high-quality trials are needed to provide better evidence for the assessment of the efficacy and safety of Chinese medicines for vascular dementia.

A compatible chord code for inputting elements of Chinese characters

A compatible chord code for inputting elements of Chinese characters (ECC) to computer was proposed. It capitalized on the graphic compatibility between ECC and chord combination of keys (CCK) on a single-handed chord keyboard with five keys. Experimental results showed that the proposed compatible chord code was better than a code that randomly mapped ECC onto CCK with respect to learning time and response time. Explicit indication of the graphic compatibility between ECC and CCK did not enhance memorizing the compatible code.

Comparison of column ozone retrievals by use of an UV multifilter rotating shadow-band radiometer with those from Brewer and Dobson spectrophotometers

The U.S. Department of Agriculture UV-B Monitoring Program measures ultraviolet light at seven wavelengths from 300 to 368 nm with an ultraviolet multifilter rotating shadow-band radiometer (UV-MFRSR) at 25 sites across the United States, including Mauna Loa, Hawaii. Column ozone has been retrieved under all-sky conditions near Boulder, Colorado (40.177 degrees N, 105.276 degrees W), from global irradiances of the UV-MFRSR 332- and 305-nm channels (2 nm FWHM) using lookup tables generated from a multiple-scattering radiative transfer code suitable for solar zenith angles (SZA's) up to 90 degrees. The most significant sources of error for UV-MFRSR column ozone retrievals at SZA's less than 75 degrees are the spectral characterizations of the filters and the absolute calibration uncertainty, which together yield an estimated uncertainty in ozone retrievals of +/-4.0%. Using model sensitivity studies, we determined that the retrieved column ozone is relatively insensitive (<+/-2%) to typical variations in aerosol optical depth, cloud cover, surface pressure, stratospheric temperature, and surface albedo. For 5 months in 1996-1997 the mean ratio of column ozone retrieved by the UV-MFRSR divided by that retrieved by the collocated Brewer was 1.024 and for the UV-MFRSR divided by those from a nearby Dobson was 1.025. The accuracy of the retrieval becomes unreliable at large SZA's of more than 75 degrees as the detection limit of the 305-nm channel is reached and because of overall angular response errors. The UV-MFRSR advantages of relatively low cost, unattended operation, automated calibration stability checks using Langley plots, and minimal maintenance make it a unique instrument for column ozone measurement.