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At least 667 records · Page 37Linked to original sources
PubMed1995

A prospective neurocognitive evaluation of children treated with additional chemotherapy and craniospinal irradiation following isolated central nervous system relapse in acute lymphoblastic leukemia.

PURPOSE: A prospective assessment of neurocognitive performance was conducted in children with acute lymphoblastic leukemia (ALL) following isolated central nervous system (CNS) relapse to evaluate the impact of additional systemic/intrathecal (IT) chemotherapy and craniospinal irradiation (CSI) upon long-term intellectual function. METHODS AND MATERIALS: Twenty-one children with ALL manifesting an isolated CNS relapse between 1984 through 1989 underwent serial evaluations of intellectual function. Neurocognitive function was measured by the full-scale intelligence quotient (FSIQ) as determined by the age-appropriate Wechsler Intelligence Scale and by achievement in reading, math, and spelling as assessed by the Wide Range Achievement Test (WRAT). Intelligence testing was initiated following isolated CNS relapse after clearance of cerebrospinal fluid (CSF) cytology but prior to CSI and continued at annual intervals for a minimum of 4 years postmeningeal failure. Protocol treatment for isolated CNS relapse consisted of reinduction and maintenance systemic therapy, intrathecal (IT) triple-agent chemotherapy, and early CSI (cranium to 24 Gy and spine to 15 Gy at 1.5 Gy/fraction) as outlined on the institutional "Total XI" trial. RESULTS: All 21 children attained secondary CNS remission and underwent the planned additional systemic/IT chemotherapy and CSI. Fourteen of the 21 children remain in secondary continuous remission, while the remaining 7 experienced a second relapse and were removed from further neurocognitive assessment. For the eight female and six male long-term survivors, mean ages at original diagnosis and at CSI were 5.7 years (range = 0.6-16.2) and 7.0 years (range = 1.8-17.0), respectively. At a median follow-up interval of 4.6 years (ranges 1.7-6.8) post-CNS relapse, comparison of group mean initial to final FSIQs revealed no statistically significant difference between the two measures (94.5 vs. 95.9, respectively, n = 11, p = 0.52). None of the children are functioning in the mentally retarded range. Final FSIQ outcome directly correlated with initial FSIQ (p = 0.00005, n = 11), age at diagnosis (p = 0.009, n = 14), and age at CSI (p = 0.011, n = 14). In addition, change between initial and final FSIQ scores inversely correlated with age at diagnosis (p = 0.009) and age at CSI (p = 0.018) but not with baseline IQ score (p = 0.41). Initial FSIQ scores were not influenced by either age at diagnosis (p = 0.12) or age at CSI (p = 0.14). Final group mean (range) WRAT scores in reading, math, and spelling were measured to be 94.7 (68-132), 95.6 (69-126), and 93.7 (77-122), respectively (n = 13). Final reading and math scores directly correlated with both age at diagnosis (p = 0.01) and age at CSI (p = 0.009). Spelling outcome did not correlate with either age at diagnosis (p = 0.25) or age at CSI (p = 0.24). Nine children are placed in regular classrooms, while the remaining five require a mixed classroom environment. CONCLUSION: In our study, children with ALL experiencing an isolated CNS relapse tolerated additional systemic/IT chemotherapy and CSI without apparent deterioration of group serial intellectual scores. However, longitudinal analyses of group intellectual measures obscured the independent impact of initial FSIQ, age at original diagnosis, and age at CSI upon individual neurocognitive outcome. Early and more intensive psychoeducational stimulation may be needed in very young children presenting with low initial FSIQ scores who are treated with CSI and additional chemotherapy following isolated CNS relapse in ALL.

Adolescent↗
PubMed1992

Polymerase chain reaction with additional primers allows identification of amplified DNA and recognition of specific alleles.

The use of additional primers in the standard two primer polymerase chain reaction (PCR) is described. This modification allows detection of a target gene in a single reaction, and identification of the amplification product obtained or recognition of a specific allele. The oligonucleotides used are internal to the original amplification primers and amplification-compatible with one of the original primers. Annealing of an additional primer to the target gene as well as to the primary amplification product will lead to the appearance of an additional smaller amplification fragment upon agarose gel electrophoresis of PCR products. Use of one or more allele-specific oligonucleotides as additional primers, in addition to two gene-specific primers, will allow recognition of different alleles of the target gene in a single PCR without further analysis except gel electrophoresis. The general applicability of the method was determined with several PCR assays for the detection of pathogenic bacteria.

Alleles↗
PubMed2005

The use of recognition information and additional cues in inferences from memory.

Goldstein and Gigerenzer's (2002) "Recognition Heuristic" (RH) was tested for its empirical validity in an experimental paradigm with induced recognition of objects. RH claims that upon inferring which of two objects (e.g., cities) scores higher on a criterion (e.g., city size), a recognized object will be chosen over an unrecognized one, if the recognition is a valid predictor of the criterion without considering additional object information. Trying to avoid potential shortcomings of former studies, we (a) used the city population task, (b) provided additional cue information only for recognized cities, and (c) had participants draw inferences from memory. Participants learned city names and additional information about some cities. They also learned that recognition and the additional information were valid predictors of the criterion "city size". In a subsequent decision phase, the additional information about the cities in memory strongly affected the inferences, suggesting that recognition information is clearly integrated into judgments, but by no means in a non-compensatory fashion that would dominate every other cue.

Adult↗
PubMed2003

Additional electrocardiographic leads in the ED chest pain patient: right ventricular and posterior leads.

In the evaluation of the patient with chest pain, the 12-lead electro cardiogram is a less-than-(ECG) perfect indicator of acute myocardial infarction (AMI), particularly when used early in the course of the acute ischemic event; this relative insensitivity for AMI results from many different issues, including a less-than-optimal imaging of certain areas of the heart. It has been suggested that the sensitivity of the 12-lead ECG can be improved if 3 additional body surface leads are used in selected individuals. Acute posterior (PMI) and right ventricular myocardial infarctions are likely to be underdiagnosed, because the standard lead placement of the 12-lead ECG does not allow these areas to be assessed directly. Additional leads frequently used include leads V(8) and V(9), which image the posterior wall of the left ventricle, and lead V(4R), which reflects the status of the right ventricle. The standard ECG coupled with these additional leads constitutes the 15-lead ECG, the most frequently used additional lead ECG in clinical practice. The use of the additional leads might not only confirm the presence of AMI, but also provide a more accurate reflection of the true extent of myocardial damage.

Aged↗
PubMed2026

Additive value of polygenic risk and family history for coronary heart disease risk stratification in two diverse US cohorts.

Whether polygenic risk, monogenic familial hypercholesterolemia (FH), and family history (FamHx) are additively informative for coronary heart disease (CHD) risk prediction across self-identified race/ethnicity (SIRE) groups has not been established. In two diverse cohorts-Electronic Medical Records and Genomics (eMERGE) phase IV (eIV; n = 19,348) and All of Us (AoU; n = 239,645)-we quantified the associations of a polygenic risk score (PRSCHD), pathogenic/likely pathogenic variants in genes associated with FH, and FamHx with CHD and evaluated their incremental value when added to the pooled cohort equations (PCEs). CHD was defined as myocardial infarction, unstable angina, or coronary revascularization. We modeled associations with multivariable logistic regression (prevalent CHD in eIV) and Cox proportional hazards (incident CHD in AoU) and characterized predictive performance with the c-statistic and reclassification and decision-curve net benefits across actionable 10-year risk thresholds. The effects of PRSCHD and FamHx were independent and additive in both cohorts and consistent across White, Black, and Latino SIRE groups. In eIV, adding PRSCHD and FamHx to the PCE increased the c-statistic for prevalent CHD from 0.719 to 0.753 (p-diff = 9.1 × 10-3) and reclassified 18.8% of participants at the 7.5% 10-year threshold, yielding approximately 4 additional true-positive CHD identifications per 1,000 screened. Net benefit gains were observed between the 7.5% and 10% thresholds across all three SIRE groups. In conclusion, PRSCHD and FamHx were independently and additively associated with CHD across major SIRE groups in two diverse cohorts in the United States (US), motivating the addition of these factors to clinical risk algorithms.

Humans↗
PubMed2006

Twenty-four-hour heart rate and blood pressure are additive markers of left ventricular mass in hypertensive subjects.

BACKGROUND: We investigated whether mean heart rate (HR(24)) and blood pressure (BP) parameters during 24-h ambulatory BP monitoring (ABP) are independent or additive markers of left ventricular (LV) mass in subjects with newly diagnosed, untreated hypertension. METHODS: A total of 250 patients (40% women, 60% men; mean age 59.6 +/- 11 years) with essential hypertension who were attending the outpatient Hypertension Unit were studied. All patients underwent 24-h ABP and HR monitoring as well as echocardiography for assessment of left ventricular (LV) dimensions and function. RESULTS: A decreasing HR24 or increasing ABP parameters (ie, systolic, diastolic, mean BP, and pulse pressure) were associated with increasing LV mass (P < .001) and wall thickness (P < .01). In multivariate analysis, after adjusting for age, gender, body surface area, body mass index, hematocrit, glucose, cholesterol, smoking, and each of the measured ABP parameters separately, decreasing HR24 was independently related to increasing LV mass in addition to ABP and body size parameters (P < .001). The addition of HR24 in different multivariate models for prediction of LV mass significantly increased the adjusted model r2 (range of r2 change: 0.039 to 0.064, P for change <.05). Decreasing HR24 or HR during daytime (6 am to 10 pm) was associated with a higher likelihood of LV hypertrophy in addition to ABP parameters (adjusted odds ratio 0.92 (CI 0.87 to 0.98), per 1 beat/min greater HR24 P = .002 and 0.93 (CI: 0.87 to 0.98), per 1 beat/min greater HR in the daytime P = .017). CONCLUSION: The 24-h HR and BP during ABP are independent and additive markers of increased LV mass in untreated hypertensive individuals.

Blood Pressure↗
PubMed2006

The impact of B-type natriuretic peptide in addition to troponin I, creatine kinase-MB, and myoglobin on the risk stratification of emergency department chest pain patients with potential acute coronary syndrome.

STUDY OBJECTIVE: The emergency department (ED) evaluation of chest pain patients with potential acute coronary syndrome is limited by the initial sensitivity of cell injury markers. BNP is increased during myocardial ischemia and is associated with adverse outcomes. We determine whether the addition of B-type natriuretic peptide (BNP) to troponin I, creatine kinase-MB (CK-MB), and myoglobin increases the sensitivity and negative predictive value (NPV) for acute myocardial infarction, acute coronary syndrome, and 30-day adverse events among chest pain patients with potential acute coronary syndrome. METHODS: A convenience sample of patients aged 30 years or older and presenting to an urban academic ED with nontraumatic chest pain, thus prompting an ECG, was enrolled, and consent was obtained. Blood samples were drawn at 0 and 90 minutes. Thirty-day follow-up was performed for all enrolled patients. Main outcomes were acute myocardial infarction, acute coronary syndrome, and 30-day events (death, acute myocardial infarction, or revascularization). BNP cutoffs were derived from receiver operator characteristics curves. The sensitivity, specificity, positive predictive value (PPV), and NPV with 95% confidence intervals (CIs) were calculated with and without BNP. Differences in sensitivity and specificity with the addition of BNP were calculated with 95% CIs, and McNemar's test was performed to compare sensitivities and specificities. RESULTS: Four hundred twenty-six patients were enrolled and analyzed. The cohort was 54.7+/-13.9 years old, 47.7% men, and 63.5% black. The outcomes were acute myocardial infarction, 39 (9.2%), acute coronary syndrome, 101 (23.7%), and 30-day adverse cardiovascular events 52 (12.2%). BNP cutoffs derived were 51, 31, and 31 pg/mL for acute myocardial infarction, acute coronary syndrome, and 30-day events, respectively. The addition of BNP showed increased sensitivity at the cost of decreased specificity for all 3 outcomes, as follows: (1) acute myocardial infarction: sensitivity: 87.2% (95% CI 72.6% to 95.7%) to 97.4% (95% CI 86.5% to 100%), difference 10.3% (95% CI-0.2% to 24.6%), P=.125; specificity: 62.3% (95% CI 57.2% to 67.1%) to 47.8% (95% CI 42.7% to 52.9%), difference 14.5% (95% CI 11.1% to %18.4), P<.0001; (2) acute coronary syndrome: sensitivity: 75.2% (95% CI 65.7% to 83.3%) to 88.1% (95% CI 80.2% to 93.7%), difference 12.9% (95% CI 7.0% to 21.0%), P=.0002; specificity: 68.0% (95% CI 62.6% to 73.0%) to 48.6% (95% CI 43.1% to 54.2%), difference 19.4% (95% CI 15.2% to 24.1%), P<.0001; (3) 30-day events: sensitivity: 71.2% (95% CI 56.9% to 82.9%) to 88.5% (95% CI 76.6% to 95.7%), difference 17.3% (95% CI 7.7% to 30.3%), P=.004; specificity: 61.8% (95% CI 56.6% to 66.7%) to 43.9% (95% CI 38.8% to 49.0%), difference 17.9% (95% CI 14.2% to 22.2%), P<.0001. There were trends toward increased NPV and decreased PPV for all outcomes, and the addition of BNP achieved a NPV of 99.5% (95% CI 97.0% to 100%) compared with 98.0% (95% CI 95.3% to 99.3%) for acute myocardial infarction. CONCLUSION: The addition of BNP as a dichotomous test to troponin I, CK-MB, and myoglobin produces increased sensitivity at a cost of decreased specificity for acute myocardial infarction, acute coronary syndrome, and 30-day adverse events. Because of this tradeoff, BNP cannot be recommended for use among all ED chest pain patients. However, the improved sensitivity may make this test useful in selected cohorts when the decreased specificity is less important.

Angioplasty, Balloon, Coronary↗
PubMed2005

Manganese and other micronutrient additions to improve yield of Agaricus bisporus.

Previous experiments have demonstrated that significant increases in yield of Agaricus bisporus mushrooms were achieved by adding a micronutrient rich fertilizer, Micromax, to the compost. This study was performed to determine the mineral(s) that are responsible for this yield improvement. An initial experiment determined that manganese was the mineral of primary importance; addition of 184 mg kg-1 Mn increased yield by 10.8%, compared to the control. Subsequent experiments demonstrated that the addition of manganese to the compost has a stimulatory effect on mushroom yields. Significant yield increases, ranging from 9.6% to 11.8% (compared to the control), were observed as a result of manganese additions varying between 50 and 300 mg kg-1. Also, data from the last set of experiments indicated that Micromax additions always resulted in greater yields indicating that micronutrients in Micromax, in addition to manganese, may be responsible for increasing yields.

Agaricus↗
PubMed2005

Study of the elution mechanism of sodium aryl sulfonates on bare silica and a cyano bonded phase with methanol-modified carbon dioxide containing an ionic additive.

The elution mechanism of sodium sulfonates on both Deltabond cyanopropyl and bare silica stationary phases with an isocratic mobile phase composed of methanol-modified CO2 wherein an ammonium salt additive was dissolved in the methanol has been studied. The presence of the additive was crucial concerning elution of the sulfonate salts. Solid state 29silicon nuclear magnetic resonance spectroscopy provided some insight concerning the interaction of the mobile phase additive with the silica-based stationary phase. Computational calculations concerning the charge distribution on various ammonium salts were performed in an effort to explain the elution behavior. Ammonium ions are believed to deactivate available silanol sites on both phases. In addition, ammonium ion is speculated to interact with the cyano groups on the bonded phase. For concentrations of additive greater than 2 mM, stationary phase coverage of ammonium ion is anticipated to exceed one monolayer for both bare and bonded silica. The acetate counter-ion is thought to facilitate elution of the anionic sulfonates from the positively charged stationary phase in a pseudo ion exchange mechanism.

Arylsulfonates↗
PubMed2004

Partition of antimicrobial additives in an intravenous emulsion and their effect on emulsion physical stability.

A number of antimicrobial agents are potentially applicable to the preservation of small-volume parenteral emulsions. However, the physical stability of these emulsions is of paramount importance in ensuring their safety, and it is possible that antimicrobial additives could reduce the emulsion stability by a number of mechanisms. We have studied the effects of several antimicrobial agents on the physical stability of Diprivan, an intravenous anaesthetic emulsion. A particular problem is that many antimicrobial additives require an acidic pH in order to be effective (e.g. sodium benzoate, sodium metabisulphite) and the emulsion surface potential is insufficient to stabilize the emulsion to coalescence under these conditions. In addition several antimicrobial agents (e.g. methyl paraben and benzoic acid) partition into the oil phase of the emulsion, requiring the use of increased concentrations to remain effective. We describe an assay technique to quantify the oil partition, liposomal partition, and droplet surface adsorption of the additives. This illustrates that significantly more additive is partitioned out of the water phase than might be predicted from simple oil/water partition experiments.

Anti-Infective Agents↗
PubMed2006

The additive effect of topical dorzolamide and systemic acetazolamide in pediatric glaucoma.

BACKGROUND: The effect of adding oral to topical carbonic anhydrase inhibitors in the management of pediatric glaucoma is unknown. METHODS: We undertook a retrospective analysis of children with a diagnosis of glaucoma before the age of 16 years who initially were treated with topical dorzolamide or dorzolamide-timolol combination and then treated with oral acetazolamide. Children who had uveitic glaucoma or who had ocular surgery within 3 months before or during oral acetazolamide therapy were excluded. Various methods of intraocular pressure (IOP) measurement were used in the study. However, in each case, the IOP was measured using the same technique, once at the last visit before the addition of oral acetazolamide and once at the first examination after the addition of oral acetazolamide. RESULTS: Twenty-two patients were included in the study with an age range of 8 months to 15 years. Seventeen children were boys. Oral acetazolamide treatment was via a daily dose (13.3 to 30 mg/kg, mean 22.5 mg/kg), and duration (6 to 31 days, mean 18.1 days). The intraocular pressure (mean +/- SD) before acetazolamide (32.2 +/- 6.5 mm Hg) was significantly different than after acetazolamide (21.8 +/- 6.3 mm Hg) with a mean difference of 10.36 mm Hg (p < 0.0001) and a mean decrease in IOP of 29.6%. CONCLUSIONS: The addition of oral acetazolamide to topical dorzolamide may provide additional reduction in IOP in some children already being treated with topical carbonic anhydrase inhibitors. This possible additive effect has not been observed in adults treated with a combination of topical and systemic carbonic anhydrase inhibitors.

Acetazolamide↗
PubMed2006

Study on the influence of additives in an industrial calcium fluoride and waterworks sludge co-melting system.

This work explores the effect of additives on the pouring temperature in a waterworks and industrial calcium fluoride sludge co-melting system. Two kinds of sludge were mixed in various ratios to find a mixing ratio at which the operating temperature for subsequent additive tests was relatively low. Various proportions of either sodium carbonate (Na2CO3) or potassium carbonate (K2CO3) reagent were added to the mixed-sludge samples to elucidate the consequent changes in pouring temperature. The experimental results revealed that the pouring temperature was lowest when calcium fluoride was mixed with waterworks sludge in a ratio of 4:6 (w/w). Adding sodium carbonate or potassium carbonate reagent to the mixed-sludge samples further reduced the pouring temperature. Increasing the amount of sodium carbonate did not significantly reduce the pouring temperature beyond that observed when 2% was added, suggesting that 2% was the optimal additional percentage of sodium carbonate. In contrast, the pouring temperature was increased when over 2% potassium carbonate was added to the mixed-sludge samples, revealing that the optimal additional percentage of potassium carbonate was also 2%. These findings indicate that both sodium carbonate and potassium carbonate can be used as additives to increase the energy efficiency of the melting process, but sodium carbonate is more operationally convenient.

Calcium Fluoride↗
PubMed2005

Zeolite synthesis from paper sludge ash at low temperature (90 degrees C) with addition of diatomite.

Paper sludge ash was partially converted into zeolites by reaction with 3M NaOH solution at 90 degrees C for 24 h. The paper sludge ash had a low abundance of Si and significant Ca content, due to the presence of calcite that was used as a paper filler. Diatomite was added to the NaOH solution to increase its Si content in order to synthesize zeolites with high cation exchange capacity. Diatomite residue was filtered from solution before addition of ash. The original ash without addition of diatomite yielded hydroxysodalite with a cation exchange capacity ca. 50 cmol/kg. Addition of Si to the solution yielded Na-P1 (zeolite-P) with a higher cation exchange capacity (ca. 130 cmol/kg). The observed concentrations of Si and Al in the solution during the reaction explain the crystallization of these two phases. The reaction products were tested for their capacity for PO(4)(3-) removal from solution as a function of Ca(2+) content, suggesting the formation of an insoluble Ca-phosphate salt. The product with Na-P1 exhibits the ability to remove NH(4)(+) as well as PO(4)(3-) from solution in concentrations sufficient for application in water purification. Both NH(4)(+) and PO(4)(3-) removal showed little variation with pH between 5 and 9. Alternative processing methods of zeolite synthesis, including the addition of ash to an unfiltered Si-NaOH solution and addition of a dry ash/diatomite mixture to NaOH solution, were tested. The third process yielded materials with lower cation exchange capacity due to formation of hydroxysodalite. The second process results in a product with relatively high cation exchange capacity, and reduces the number of processing steps necessary for zeolite synthesis.

Adsorption↗
PubMed2005

Additional Her 2/neu gene copies in patients with Sézary syndrome.

BACKGROUND: Her 2/neu gene amplification has been reported in several types of cancer. Monoclonal antibodies against the Her 2/neu receptor are used as a treatment in e.g. metastatic breast cancer. AIM: The aim of this study was to determine the frequency of additional Her 2/neu gene copies in relations to the number of chromosome 17 centromeres of patients with Sézary syndrome. METHODS: Fluorescence in situ hybridization (FISH) with probes specific for the Her 2/neu gene locus and the centromere of chromosome 17 was performed on nuclei from peripheral blood cells of 9 patients with Sézary syndrome. For analysis of Her 2/neu protein expression immunostaining was performed. In addition, FISH was used to analyze distribution of typical lymphocytes on cryo-cut sections of affected skin of two patients. RESULTS: 7/9 cases showed additional Her 2/neu gene copies in relation to the number of chromosome 17 centromeres. 4/5 cases with additional Her 2/neu gene copies in which immunostaining was performed expressed Her 2/neu protein. On cryo-cut sections atypical lymphocytes with additional Her 2/neu gene copies were detected in the dermis as well as in the epidermis of affected skin. DISCUSSION: These data suggest that Her 2/neu might be involved in the pathogenesis of Sézary syndrome and that Her 2/neu might be a promising target for antitumor therapy in a subgroup of patients.

Aged↗
PubMed2004

Chemotherapy of breast cancer-additive anticancerogenic effects by 2-methoxyestradiol?

2-Methoxyestradiol (2ME) is an endogenous estradiol metabolite, which acts antiproliferative in various tumor cell lines independent of the hormone receptor status. We investigated whether combinations of 2ME with various chemotherapeutic or endocrine compounds may result in an additive effect on the proliferation of human breast cancer cells. The breast cancer cell lines MCF-7 (receptor-positive), BM (receptor-negative) and a MCF-7 line transfected with the aromatase gene were used. All cell lines were incubated in the concentration range of 0.8 microM to 25 microM with 2ME alone and in equimolar combinations with the following compounds: epirubicine, daunorubicine, paclitaxel, docetaxel, carboplatin, vinorelbine, 5-fluorouracil, mafosfamide and 4-OH tamoxifen. The effect of letrozole and 2ME alone and in equimolar combinations was tested in the concentration range of 0.6 to 1 microM. Proliferation was measured after 4 days using the ATP-chemosensitivity test. In MCF-7 cells 2ME in combination with 4OH-tamoxifen, epirubicine, docetaxel, 5-fluoprouracil, mafosfamide and carboplatin led to an additive effect. In BM cells only 2ME combined with 4OH-tamoxifen, daunorubicine and mafosfamide showed an additive action. Both letrozole and 2ME were nearly similar effective in inhibition of the aromatase gene. Here no additive effect was found. 2ME displayed antiproliferative actions in various human breast cancer cells. In addition 2ME was able to increase the antiproliferative property of certain antihormones and cytostatic substances. Furthermore 2ME exhibits a similar property as compared to letrozole in inhibiting the aromatase activity. Since 2ME was well tolerated in a recently conducted phase II trial in patients with refractory metastatic breast cancer, the combination of 2ME with chemotherapeutics or antihormones may offer a new clinically relevant treatment regimen.

2-Methoxyestradiol↗
PubMed2006

Studies of thiol additions of silane coupling agents by vibrational spectroscopy.

Raman and infrared spectroscopies have been used to determine the addition reaction of mercaptopropyltrimethoxysilane (MPTMS) to allyltrimethoxysilane (ATMS) and 7-octenyltrichlorosilane based on the vibrational intensity variation of thiol and vinyl groups in the reaction mixtures. Due to the distinct and moderate intensity of Raman bands observed in the present experiment, the identification with Raman spectroscopic method is more sensitive than that with FTIR spectroscopy. In the presence of UV radiation, thiol addition reaction has been observed in the direct mixing samples of silanes. Hybrid sol-gels prepared with the use of MPTMS and ATMS as precursors in both acidic and basic conditions have revealed the progression of thiol addition under the UV radiation exposure. UV radiation is similarly effective to induce the thiol addition in the sol-gel coated aluminum tiles. Without UV radiation, the use of free radical initiator in the sol-gel samples might also help to induce the addition reaction.

Aluminum↗
PubMed2005

Risk assessment of combined photogenotoxic effects of sunlight and food additives.

The presence of flavored colorants (peach and raspberry), flavors (caramel, citric acid and vanilla) and food preservatives (sodium nitrite, sodium nitrate, sodium benzoate, benzoic acid, potassium sorbate and sodium chloride) in Escherichia coli suspension during exposure to sunlight did not change the extent of cell survival. No effect on viability and mutation induction (kanamycin resistant) was also seen when cells were kept in contact with any of the additives for 80 min in the dark. However, when the relevant additive was present in cell suspension during sunlight exposure the number of induced mutations was increased to varying extents over that seen with sunlight alone. Raspberry and peach increased the number of mutations in a dose dependent manner, while vanilla produced mutations in an additive fashion. Nitrite, nitrate, benzoate, sorbate and benzoic acid increased mutation somewhat additively over that of sunlight. Sodium chloride and citric acid were not effective. The impact of this investigation reflects the significance of combination of sunlight and chemical food additives as potential risk, which requires special attention and necessitates further investigations to evaluate the risk.

Escherichia coli↗
PubMed2004

Decrease in glutathione content in boar sperm after cryopreservation. Effect of the addition of reduced glutathione to the freezing and thawing extenders.

Although glutathione content in boar spermatozoa has been previously reported, the effect of reduced glutathione (GSH) on semen parameters and the fertilizing ability of boar spermatozoa after cryopreservation has never been evaluated. In this study, GSH content was determined in ejaculated boar spermatozoa before and after cryopreservation. Semen samples were centrifuged and GSH content in the resulting pellet monitored spectrophotometrically. The fertilizing ability of frozen-thawed boar sperm was also tested in vitro by incubating sperm with in vitro matured oocytes obtained from gilts. GSH content in fresh semen was 3.84 +/- 0.21 nM GSH/10(8) sperm. Following semen cryopreservation, there was a 32% decrease in GSH content (P < 0.0001). There were significant differences in sperm GSH content between different boars and after various preservation protocols (P = 0.0102 ). The effect of addition of GSH to the freezing and thawing extenders was also evaluated. Addition of 5 mM GSH to the freezing extender did not have a significant effect on standard semen parameters or sperm fertilizing ability after thawing. In contrast, when GSH was added to the thawing extender, a dose-dependent tendency to increase in sperm fertilizing ability was observed, although no differences were observed in standard semen parameters. In summary, (i) there was a loss in GSH content after cryopreservation of boar semen; (ii) addition of GSH to the freezing extender did not result in any improvement in either standard semen parameters or sperm fertilizing ability; and (iii) addition of GSH to the thawing extender resulted in a significant increase in sperm fertilizing ability. Nevertheless, future studies must conclude if this is the case for all boars. Furthermore, since addition of GSH to the thawing extender did not result in an improvement in standard semen parameters, this suggests that during the thawing process, GSH prevents damage of a sperm property that is critical in the fertilization process but that is not measured in the routine semen analysis.

Animals↗