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PubMed2000

Utility of step sections: demonstration of additional pathological findings in biopsy samples initially diagnosed as actinic keratosis.

OBJECTIVES: To discover additional diagnostic findings on step sections of biopsy samples showing features of actinic keratosis on the initial section and to correlate such findings with clinical and histological variables. DESIGN: Prospective study comparing initial histological findings with those noted on deeper tissue levels. SETTING: University-based dermatopathology practice. PATIENTS: Fifty-seven patients (36 men and 21 women) with biopsy samples from 69 skin lesions. MAIN OUTCOME MEASURES: Identification of additional pathological diagnoses in step sections and correlation with clinical diagnosis, size and location of lesion, history of skin cancer or immunosuppression, size and handling of specimen, and presence of ulceration on the initial level. RESULTS: Additional diagnostic findings were present on step sections in 23 specimens (33%), including 9 (13%) with squamous cell carcinoma in situ, 3 (4%) with basal cell carcinoma, and 2 (3%) with invasive squamous cell carcinoma. Three variables were significantly correlated with the discovery of cancer on step sections: (1) ulceration on the first level, (2) clinical diagnosis of skin cancer, and (3) history of skin cancer diagnosed by biopsy examination. The latter 2 variables were also correlated with the discovery of any additional finding, whether benign or malignant, on step sections. CONCLUSIONS: In biopsy samples initially diagnostic of actinic keratosis, examination of step sections contributes clinically important information. Step sections are particularly useful when a clinical diagnosis of skin cancer is present. The results of this study confirm the pathogenetic importance of actinic keratosis as a precursor to fully evolved malignant neoplasia and suggest that such lesions merit thorough histological study.

Adult↗

PubMed2004

Additivity of bimatoprost or travoprost to latanoprost in glaucomatous monkey eyes.

OBJECTIVE: To compare the ocular hypotensive effect of the commercially available preparations of bimatoprost or travoprost added to latanoprost in monkey eyes with laser-induced unilateral glaucoma. METHODS: Four monkeys with unilateral laser-induced glaucoma were used in each treatment group and received drops in the glaucomatous eye only. Intraocular pressure (IOP) was measured hourly for 6 hours, beginning at 9:30 am on day 1 (untreated baseline), days 6 and 7 (single-agent therapy), and days 13 and 14 (2-drug combination therapy). On days 2 through 7, 1 drop of the scheduled single agent was given immediately after the 9:30 am IOP measurement, and on days 8 through 14, the second scheduled drug was given 5 minutes after the first. The following 5 different dosing protocols were studied: latanoprost with bimatoprost added, bimatoprost with latanoprost added, latanoprost with travoprost added, travoprost with latanoprost added, and latanoprost with a second dose of latanoprost added. RESULTS: There were no statistically significant (P =.95) differences among the mean baseline IOPs in any of the 5 treatment groups. When applied as single agents, latanoprost, bimatoprost, and travoprost all produced significant (P<.05) and equivalent (P =.98) reductions in IOP. The mean +/-SEM maximum reduction (P<.05) from baseline IOP was 7.0 +/- 0.4 mm Hg (20% reduction) with travoprost alone, 6.5 +/- 1.6 mm Hg (18%) with bimatoprost alone, and 7.5 +/- 1.0 mm Hg (22%) with latanoprost alone. The mean +/-SEM maximum additive reductions in IOP were 3.0 +/- 0.6 mm Hg (P<.05) for travoprost added to latanoprost; 2.0 +/- 0.4 mm Hg (P<.05) for latanoprost added to travoprost; 4.8 +/- 1.3 mm Hg (P<.05) for bimatoprost added to latanoprost; 4.3 +/- 0.6 mm Hg (P<.05) for latanoprost added to bimatoprost; and 0.3 +/- 0.5 mm Hg (P>.60) for latanoprost added to itself. The combination of bimatoprost and latanoprost produced a greater (P<.05) lowering of IOP at trough and peak than the combination of travoprost and latanoprost. CONCLUSIONS: Latanoprost, bimatoprost, and travoprost used as monotherapy produced significant and equivalent reductions in IOP in glaucomatous monkey eyes. The IOP effects of the commercial concentrations of bimatoprost or travoprost were additive to that of latanoprost, with bimatoprost showing a greater additive response than travoprost. Clinical Relevance Because treatment with multiple medications is common among patients with glaucoma, determining which glaucoma medications produce an additive ocular hypotensive response when used in combination has practical implications for clinicians.

Amides↗

PubMed1997

Genealogy, natural history, and phenotype of Alström syndrome in a large Acadian kindred and three additional families.

We describe a large Acadian kindred including 8 Alstrom Syndrome (AS) patients, with an age range of 4 to 26 at the time of clinical assessment. The affected subjects come from 5 nuclear families within this kindred. The phenotype includes early childhood retinopathy, progressive sensorineural hearing loss, truncal obesity, and acanthosis nigricans. In addition, hyperinsulinemia and hypertriglyceridemia with normal cholesterol levels were observed in most affected individuals tested. Non-insulin dependent diabetes mellitus and growth retardation appear to be age-related manifestations that occur post-adolescence. Younger affected children are not overtly hyperglycemic and are normal or above average height for age. Although the AS patients in kindred 1 presumably carry the same mutation, many manifestations of the disease are variable. For example, of the 8 children in the Acadian kindred, 4 have scoliosis, 2 have had infantile cardiomyopathy, 2 are hypothyroid, 1 has had hepatic dysfunction and is hypertensive, and 4 have developed asthma. Seven subjects described in this kindred exhibit developmental delay. One additional manifestation not described widely in the literature, advanced bone age, was observed in all subjects tested. The clinical data from this large Acadian kindred, together with information obtained from 4 additional AS patients in 3 unrelated kindreds, confirm and extend clinical observations previously described. In addition, the Acadian kindred with multiple affected individuals, probably arising from a common founder, should allow for identification of the chromosomal localization of a gene causing AS.

Abnormalities, Multiple↗

PubMed1999

Effects of pulse addition of carbon sources on continuous cultivation of Escherichia coli containing a recombinant E. coli gapA gene.

At high glucose concentrations, Escherichia coli produces acetate (Crabtree effect). To look for the influence of glucose and/or acetate in the medium on the expression of a recombinant gene in E. coli, the effect of a pulse addition of glucose, on transcription of a cloned E. coli gapA gene and the resulting glyceraldehyde-3P-dehydrogenase activity (GAPDH), was tested during continuous cultivation of E. coli HB101 transformed with the plasmid pBR::EcogapA. Stable continuous cultures were established in a semi-synthetic medium supplemented with 5 g/L of glucose. After the addition of 7 g of glucose within a few seconds, gapA gene expression was strongly and very rapidly induced. As shown by primer-extension analysis, promoter P1, one of the four transcriptional promoters of the gapA gene, was strongly activated, and GAPDH activity increased. However, after rapid glucose consumption, acetate was produced and acetate concentrations above 2 g/L induced stress conditions. This is shown by a strong activation of promoter P2, that is recognized by the stress specific Esigma32 RNA polymerase. During this period, the total cellular RNA content was strongly diminished. Later, when acetate was partially consumed a high level of total RNA was restored, translation was efficient and a regular increase of the GAPDH-specific activity was observed. The transitions between glucose metabolism, acetate production and the end of acetate consumption, were marked by large increases in RNase and protease activities. For comparison, pulse-addition experiments were also performed with serine and alanine. A transient increase of GAPDH production associated with an increase in biomass was also found for serine that can be utilized as an energy source, whereas the addition of alanine, which is only incorporated into newly synthesized proteins, did not increase GAPDH production. The implication of these data for overproduction of recombinant proteins in E. coli is discussed.

Acetic Acid↗

PubMed1997

Synthetic and model computational studies of molar rotation additivity for interacting chiral centers: a reinvestigation of van't Hoff's principle.

When plane-polarized light impinges on a solution of optically active molecules, the polarization of the light that emerges is rotated. This simple phenomenon arises from the interaction of light with matter and is well understood, in principle, van't Hoff's rule of optical superposition correlates the molar rotation with the individual contributions to optical activity of isolated centers of asymmetry. This straightforward empirical additivity rule is rarely used for structure elucidation nowadays because of its limitations in the assessment of conformationally restricted or interacting chiral centers. However, additivity can be used successfully to assign the configuration of complex natural products such as hennoxazole A if appropriate synthetic partial structures are available. Therefore, van't Hoff's principle is a powerful stereochemical complement to natural products' total synthesis. The quest for reliable quantitative methods to calculate the angle of rotation a priori has been underway for a long time. Both classical and quantum methods for calculating molar rotation have been developed. Of particular practical importance for determining the absolute structure of molecules by calculation is the manner in which interactions between multiple chiral centers in a single molecule are included, leading to additive or non-additive optical rotation angles. This problem is addressed here using semi-empirical electronic structure models and the Rosenfeld equation.

Chemistry, Physical↗

PubMed1990

A randomized comparison of methotrexate dose and the addition of bleomycin to CHOP therapy for diffuse large cell lymphoma and other non-Hodgkin's lymphomas. Cancer and Leukemia Group B study 7851.

In 1978, Cancer and Leukemia Group B initiated a randomized study to determine the usefulness of the addition of bleomycin and/or high-dose methotrexate to standard therapy for the treatment of certain adult non-Hodgkin's lymphomas. Between 1978 and 1985, 177 patients with diffuse large cell lymphoma (DLCL) and 97 patients with other intermediate-grade non-Hodgkin's lymphoma were randomized to receive therapy with three courses of cyclophosphamide, adriamycin, vincristine, and prednisone (CHOP) every 3 weeks with or without low-dose bleomycin by continuous IV infusion. Responders after three courses were further randomized to 3 weeks of therapy with either high-dose methotrexate (3 gm/m2/week intravenously with leucovorin rescue) or standard-dose methotrexate (30 mg/m2/week orally without rescue). Therapy was concluded with three additional courses of CHOP. Neither the addition of low-dose infusion bleomycin nor the use of high-dose rather than low-dose methotrexate had significant effects on response for patients with DLCL; complete response rates for the four treatment programs ranged from 47% to 51%. Median failure-free survival (FFS) for the entire group of DLCL patients was 12 months; 5-year FFS was 27%. There was no significant effect on FFS from the addition of either low-dose bleomycin to CHOP (5-year FFS: CHOP, 28%; CHOP-B, 26%, P = 0.81), or from the use of different doses of methotrexate (5-year FFS: high-dose, 34%; standard-dose, 33%, P = 0.51). Patients with follicular large cell lymphoma, with or without diffuse areas, had a better FFS (5-year FFS, 47%) than patients with DLCL (5-year FFS, 27%), while the patients with the other histopathologic subtypes of diffuse lymphomas had the poorest FFS (5-year FFS, 16%).

Aged↗

PubMed1992

Randomized adjuvant trial to evaluate the addition of tamoxifen and PSK to chemotherapy in patients with primary breast cancer. 5-Year results from the Nishi-Nippon Group of the Adjuvant Chemoendocrine Therapy for Breast Cancer Organization.

BACKGROUND: A randomized adjuvant trial was conducted from October 1982 to January 1985 to evaluate the addition of tamoxifen (TAM) to combination chemotherapy with perioperative mitomycin C (MMC) and ftorafur (FT) for patients with estrogen receptor (ER)-positive tumors and the addition of PSK, a biologic response modifier, to MMC+FT chemotherapy for patients with ER-negative tumors in operable Stage IIA, IIB, and IIIA cancer. The doses used were 20 mg of oral TAM daily, 600 mg of oral FT daily, and 3 g of oral PSK daily for 2 years. Intravenous MMC (13 mg/m2) was given on the day of operation. METHODS: A total of 967 patients were entered and randomized by stratification based on ER status and staging (1978 International Union Against Cancer [UICC] criteria at the time of trial execution). Of 967 patients, 914 (94.5%) were evaluable. At 5-year follow-up, significant prolonged overall survival (OS) and relapse-free survival (RFS) times were seen with the addition of TAM in patients with ER-positive and Stage IIIA T3N0 cancer (1987 UICC-American Joint Committee on Cancer [AJCC] criteria); however, no significant survival benefit from TAM was seen in patients with ER-positive and Stage IIA T2N1 cancer. There was no significant difference between regimens, with or without PSK, in patients with ER-negative disease. RESULTS: Results of subset analyses suggested a benefit from TAM in postmenopausal patients with ER-positive and Stage IIA T2N1 cancer and a benefit from PSK in patients with node-negative, ER-negative, and Stage IIA T2N1 cancer. CONCLUSIONS: The 5-year results of the current trial showed a survival advantage by the addition of TAM to chemotherapy in patients with ER-positive and Stage IIIA T3N0 cancer.

Adjuvants, Immunologic↗

PubMed2000

Addition of intravenous aminophylline to beta2-agonists in adults with acute asthma.

BACKGROUND: Aminophylline has been used extensively in acute asthma, but its role is unclear especially with respect to any additional benefit when added to beta2-agonists. OBJECTIVES: To determine the magnitude of effect of the addition of intravenous aminophylline to beta2-agonists in adult patients with acute asthma treated in the emergency setting. SEARCH STRATEGY: Studies were identified from the following sources: The Cochrane Airways Group register (derived from MEDLINE, EMBASE, CINAHL standardised searches), hand searched respiratory journals and meeting abstracts. Potentially relevant articles were obtained, and their bibliographic lists were hand searched for additional articles. The search included searches of the database up to 1999. SELECTION CRITERIA: Randomised controlled trials comparing intravenous aminophylline versus placebo in adults with acute asthma and treated with beta-adrenergic agonists. Patients could be treated with or without corticosteroids or other bronchodilators. DATA COLLECTION AND ANALYSIS: A total of 210 abstracts were identified. Two independent reviewers selected a total of 27 eligible studies for possible inclusion, in which quality assessment was performed and a third reviewer was used to adjudicate disagreements. Peak expiratory flow (PEFR) and forced expiratory volume in the first second (FEV1) data were extracted and entered in Review Manager from these studies. Information not obtained from the authors was estimated from graphs. All data were entered and double checked by two reviewers. Results are reported as weighted mean differences (WMD) or odds ratio (OR), both with 95% confidential intervals (CI). MAIN RESULTS: Fifteen trials were included. Overall, the quality of the studies was only moderate; concealment of allocation was assessed as clearly adequate in only seven (45%) of the trials. The doses of aminophylline and other medications and the severity of asthma varied between studies. There was no statistically significant effect of aminophylline on airflow outcomes at any time period. The aminophylline treated group had higher values of PEFR at 12 (PEFR 8 L/min or 2.3%) and 24 hours (PEFR 22 L/min or 6.4%), but these were not significant (p>0.05). Two subgroup analyses were performed by grouping studies according to mean baseline airflow limitation (n = 11 studies) and the use of any steroids (n = 9 studies). There was no relationship between baseline airflow limitation nor the use of steroids on the effect of aminophylline. Aminophylline treated patients reported more palpitations/arrhythmias (OR: 2.9; 95% CI: 1.5 to 5.7) and vomiting (OR: 4.2; 95% CI 2.4 to 7.4), but no difference was found in tremor or hospital admissions. REVIEWER'S CONCLUSIONS: In acute asthma, the use of intravenous aminophylline did not result in any additional bronchodilation compared to standard care with beta-agonists. The frequency of adverse effects was higher with aminophylline. No subgroups in which aminophylline might be more effective could be identified. These results should be added to consensus statements and guidelines.

Adrenal Cortex Hormones↗

PubMed2002

Metal-template-directed synthesis of diphosphorus compounds through intramolecular phosphinidene additions.

Heating the nonchelating cis-bis-7-phosphanorbornadiene-[Mo(CO)4] complex (13) results in the thermal decomposition of one of the 7-phosphanorbornadiene groups. The phosphinidene thus generated adds intramolecularly to a C=C bond of the other ligand to give the novel diphosphorus complex 14. This reaction constitutes a metal-template-directed synthesis. Likewise, the intramolecular phosphinidene addition to the C=C bond of a Mo-phospholene ligand affords the diphos complex 18. Its crystal structure exhibits an extremely small P-Mo-P bite-angle for a five-membered chelate ring. The similar intramolecular 1,2-addition to a C=C bond of a phosphole ligand gives a highly strained, unstable intermediate product. Scission of its P-Mo bond generates a free coordination site, which is then occupied by either CO or a phosphole to yield complexes 22 and 23, respectively. The analogous intermolecular addition of [PhPW(CO)5] to a [phosphole-W(CO)5] complex gives the di-[W(CO)5] complexed adduct 28. The directing effect of the metal on the intra- and intermolecular additions is discussed.

Journal Article↗

PubMed2002

The effect of ajmalicine spiking and resin addition timing on the production of indole alkaloids from Catharanthus roseus cell cultures.

The potential for the feedback inhibition of indole alkaloid synthesis was investigated by spiking suspension cultures of Catharanthus roseus with 0, 9, or 18 mg/L ajmalicine on day 0. The production of ajmalicine, catharanthine, and serpentine were inhibited in a dose-dependent manner. The inhibition was transient as the exogenous ajmalicine was ultimately either metabolized in the medium or within the cell. The addition of neutral resin has previously been shown to enhance ajmalicine production. To minimize product inhibition and product metabolism, Amberlite XAD-7 resin was added to immobilized cultures of C. roseus starting on either day 0, 5, or 15, and fresh resin was exchanged for spent resin every 5 days. The addition of resin did not decrease the viability of the culture. Growth was reduced only in cultures with resin added on day 0. Alkaloid production was enhanced to different extents by the timing of resin addition, suggesting that feedback inhibition or product metabolism was present throughout the culture period. Ajmalicine recovery was nearly 100% when the resin was added initially either on day 0 or day 5. Ajmalicine recovery was reduced to 55% when the resin was added later in the culture period starting on day 15, presumably because of resin saturation or the inaccessibility of alkaloids trapped in the vacuole. Delaying the addition of XAD-7 resin until 5 days after the start of the culture resulted in the highest improvement in ajmalicine production, i.e approximately 70% and also resulted in the complete recovery of ajmalicine from the cell.

Acrylic Resins↗

PubMed2003

Pulsed addition of limiting-carbon during Aspergillus oryzae fermentation leads to improved productivity of a recombinant enzyme.

Fungal morphology in many filamentous fungal fermentations leads to high broth viscosity which limits oxygen mass transfer, and often results in reduced productivity. The objective in this study was to determine if a simple, fed-batch, process strategy-pulsed addition of limiting-carbon source-could be used to reduce fungal broth viscosity, and increase productivity of an industrially relevant recombinant enzyme (glucoamylase). As a control, three Aspergillus oryzae fed-batch fermentations were carried out with continuous addition of limiting-carbon. To determine the effect of pulse-feeding, three additional fermentations were carried out with limiting-carbon added in 90-second pulses, during repeated five-minute cycles. In both cases, overall carbon feed-rate was used to control dissolved oxygen concentration, such that increased oxygen availability led to increased addition of limiting-carbon. Pulse-fed fermentations were found to have smaller fungal mycelia, lower broth viscosity, and improved oxygen mass transfer. As a result, more carbon was added to pulse-fed fermentations that led to increased enzyme productivity by as much as 75%. This finding has significant implications for the bioprocessing industry, as a simple process modification which is likely to cost very little to implement in most production facilities, has the potential to substantially increase productivity.

Aspergillus oryzae↗

PubMed1995

Additional renal veins: incidence and morphometry.

Modern surgical and radiological techniques dictate a reappraisal and definition of the renal venous anatomy. The purpose of this study was to investigate the incidence and morphometry of additional renal veins. One hundred fifty-three morphologically normal en bloc renal specimens were randomly selected from post-mortem examinations. Single additional renal veins were common on the right side (26%), while it was rare on the left side (2.6%). Second additional renal veins occurred infrequently on the right side (5%). Since additional renal veins may be encountered more than occasionally, it is worthwhile emphasizing their presence particularly to the transplant surgeon and the angiologist.

Cadaver↗

PubMed2006

Micelle-to-vesicle transition induced by organic additives in catanionic surfactant systems.

A micelle-to-vesicle transition (MVT) induced by the addition of a series of apolar hydrocarbons (n-butylbenzene, n-hexane, n-octane, and n-dodecane) to the catanionic surfactant system n-dodecyltriethylammonium bromide/sodium n-dodecylsulfate (DTEAB/SDS) has been investigated for the first time by means of rheology and turbidity measurements, dynamic light scattering (DLS), and transmission electron microscopy (TEM). Interestingly, a MVT can take place within certain micellar regions, which are dependent on the structure and chain length of the hydrocarbon. However, these hydrocarbons are unable to induce a MVT in another catanionic surfactant system, namely, n-dodecyltriethylammonium bromide/sodium n-dodecylsulfonate (DTEAB/SDSO(3)), in which the molecular interactions are weaker than in the DTEAB/SDS system. On the other hand, polar additives, such as n-octanol and n-octylamine, exhibit much higher efficiency and activity in inducing MVT than hydrocarbons in both DETAB/SDS and DTEAB/SDSO(3). Moreover, DLS, TEM, and time-resolved fluorescence quenching (TRFQ) results demonstrate that the ratio of vesicles to micelles in the system can be actively controlled by addition of polar additives. Possible mechanisms for the above phenomena are presented, and the potential application of controllable micelle/vesicle systems in the synthesis of tailored bimodal mesoporous materials is discussed.

Alkanes↗

PubMed2004

Memory effect of diethylamine mobile phase additive on chiral separations on polysaccharide stationary phases.

The existence of a memory effect for amine additives on polysaccharide chiral stationary phases has often been suggested, but not clearly demonstrated. Demonstration of this effect is made difficult by the uncertainty as to which analytes benefit from use of amine additives and, typically, an unclear history of column use. In this work, analytes were selected for differences in their behavior with and without additives. Columns were used with no prior history. A persistent memory effect was demonstrated on a CHIRALPAK AD-H column in hexane-based mobile phases. This effect was short-lived, with polar organic mobile phases. Memory was short-lived on a CHIRALCEL OJ-H column. Flushing with isopropanol was shown to remove most of the memory effect. Compounds expected to require amine additives on CHIRALCEL OD-H column did not. Acid treatment of the AD-H and OD-H columns changed their performance, which was subsequently restored by the incorporation of amine.

Chromatography, Liquid↗

PubMed2005

Applications of ammonium trifluoroacetate as an additive for elution of chiral acids and bases from derivatized polysaccharide stationary phases.

The ability ammonium trifluoroacetate as an additive for elution of acids and bases from derivatized polysaccharide chiral stationary phases was first observed in the process of developing normal-phase chiral HPLC methods in our lead-generation programs. To demonstrate this ability on a broader scale, chiral HPLC methods containing this additive in the mobile phases were developed to resolve selected acidic, basic, and neutral racemates, which are considered standards in the pharmaceutical industry and for which published methods exist. The mobile phases of these published methods contain acidic and/or basic additives (e.g., trifluoroacetic acid or diethylamine). This article demonstrates the versatility of ammonium trifluoroacetate additive in resolving the enantiomers of acidic and basic racemates on the same derivatized polysaccharide chiral columns. This resolution is achieved without changing the mobile phase between the analysis of acidic and basic racemates and also without observation of stationary-phase "memory effect." This chiral method development strategy can result in significant savings of cost and time.

Journal Article↗

PubMed1998

Additional antianginal and anti-ischemic efficacy of mibefradil in patients concomitantly treated with long-acting nitrates for chronic stable angina pectoris.

BACKGROUND: Mibefradil, a newly approved antihypertensive and antianginal drug, is the first member of a new class of calcium antagonists (CAs), the tetralol derivatives, that selectively blocks T-type Ca2+ channels in contrast to classical CAs which, at therapeutic concentrations, block only L-type Ca2+ channels. Since patients with chronic stable angina pectoris typically may be treated with the combination of a long-acting nitrate and a CA, the additive efficacy and safety of mibefradil in combination with nitrate therapy needs to be determined. HYPOTHESIS: This study was designed to assess the efficacy, tolerability, and safety of mibefradil when added to long-acting nitrate therapy in patients with chronic stable angina pectoris. METHODS: Following a 1-week placebo run-in period, patients were randomized to receive either mibefradil 50 mg (n = 96) or placebo (n = 93) once daily in addition to their nitrate therapy. After 2 weeks of active treatment, patients receiving the mibefradil were force titrated to 150 mg once daily for an additional 2 weeks. Exercise tolerance tests (ETTs) were performed at the end of Weeks 2 and 4; patients also maintained an anginal diary during the 4-week treatment period. RESULTS: After 2 weeks of treatment with 50 mg mibefradil (within the current recommended dose range), a statistically significant but modest increase in total exercise duration was observed (treatment effect 16.4 s, p = 0.04). Similarly, there was a significant increase in time to onset of ischemia (treatment effect 26 s, p = 0.008). The adverse event profile of the 50 mg dose was indistinguishable from placebo, indicating that this dose was extremely well tolerated. At Week 4, the mibefradil-treated patients were taking 150 mg, which is above the current recommended dose range. The increase in total exercise duration was larger for the mibefradil 150 mg group than for the placebo group. For the intent-to-treat population, this difference did not reach statistical significance, whereas in the standard population it did (treatment effect 21 s, p = 0.05). The other two ETT variables, time to onset of angina and time to onset of 1 mm ST-segment depression, demonstrated significantly greater effect with mibefradil 150 mg (treatment effects 40 s, p = 0.002, and 55 s, p < 0.001, respectively, for the intent-to-treat population). Mibefradil 150 mg was associated with more adverse events than placebo, specifically, dizziness, leg edema, and postural hypotension. CONCLUSIONS: This study demonstrates that mibefradil 50 mg once daily in the setting of the background long-acting nitrate therapy produces additive antianginal and anti-ischemic effects and is extremely well tolerated.

Adolescent↗

PubMed2006

Hydrogen atom and hydride anion addition to adenine: structures and energetics.

The radicals and anions derived from the 9H tautomer of adenine by adding a hydrogen atom to one of the four double bonds of the adenine framework have been studied. Computations were carried out using a carefully calibrated density functional (B3LYP) method and basis set (DZP++). Optimized geometries, energies, and vibrational frequencies are predicted for eight radicals and anions. The radicals are found to lie in a range of 22 kcal mol(-1), with the radical derived by addition to the C(8) carbon atom being the lowest lying energetically. The anions are predicted to be bound species in the gas phase with an energetic range of 43 kcal mol(-1). Anions produced by addition of a hydride ion to adenine carbon atoms are found to be the most favorable. Six of the anions are predicted to be stable species with respect to electron detachment. The adiabatic electron affinities, vertical electron affinities, and vertical detachment energies are computed for the first time. Electron affinities for these radicals range from 0.0 to 2.0 eV. Radicals produced by addition to a nitrogen atom have near-zero adiabatic electron affinities, while radicals produced by addition at carbon atoms have considerably higher electron affinities.

Adenine↗

PubMed2006

Bmp2 and Gata4 function additively to rescue heart tube development in the absence of retinoids.

We used the vitamin A-deficient (VAD) quail model to investigate the retinoid-dependent mechanism that regulates heart tube development. We showed previously that decreased levels of Gata4 in cardiogenic mesoderm and endoderm correlate with the cardiomyopathy caused by VAD, but that this could be rescued by transplanting normal anterior endoderm. Bmp2 is a known cardiogenic factor that is expressed normally in lateral plate mesoderm and cardiac-associated pharyngeal endoderm. Here we show that (like Gata4) transcripts encoding Bmp2 and BMP-dependent signaling activity are decreased throughout the heart-forming region of the VAD embryo. Addition of Bmp2 protein or forced expression of Gata4 in cultured VAD embryos leads to a partial rescue of the cardiomyopathy, and addition of both Bmp2 and Gata4 has an additive positive effect. Our data are consistent with a requirement for retinoid signaling to maintain expression of Bmp2, which regulates Gata4, and in addition acts with Gata4 to regulate genes important for normal morphogenesis of the primitive heart tube.

Animals↗