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1.
Mol Phylogenet Evol ; 142: 106659, 2020 01.
Article in English | MEDLINE | ID: mdl-31639525

ABSTRACT

A major goal of phylogenetic systematics is to understand both the patterns of diversification and the processes by which these patterns are formed. Few studies have focused on the ancient, species-rich Magnoliales clade and its diversification pattern. Within Magnoliales, the pantropically distributed Annonaceae are by far the most genus-rich and species-rich family-level clade, with c. 110 genera and c. 2,400 species. We investigated the diversification patterns across Annonaceae and identified traits that show varied associations with diversification rates using a time-calibrated phylogeny of 835 species (34.6% sampling) and 11,211 aligned bases from eight regions of the plastid genome (rbcL, matK, ndhF, psbA-trnH, trnL-F, atpB-rbcL, trnS-G, and ycf1). Twelve rate shifts were identified using BAMM: in Annona, Artabotrys, Asimina, Drepananthus, Duguetia, Goniothalamus, Guatteria, Uvaria, Xylopia, the tribes Miliuseae and Malmeeae, and the Desmos-Dasymaschalon-Friesodielsia-Monanthotaxis clade. TurboMEDUSA and method-of-moments estimator analyses showed largely congruent results. A positive relationship between species richness and diversification rate is revealed using PGLS. Our results show that the high species richness in Annonaceae is likely the result of recent increased diversification rather than the steady accumulation of species via the 'museum model'. We further explore the possible role of selected traits (habit, pollinator trapping, floral sex expression, pollen dispersal unit, anther septation, and seed dispersal unit) in shaping diversification patterns, based on inferences of BiSSE, MuSSE, HiSSE, and FiSSE analyses. Our results suggest that the liana habit, the presence of circadian pollinator trapping, androdioecy, and the dispersal of seeds as single-seeded monocarp fragments are closely correlated with higher diversification rates; pollen aggregation and anther septation, in contrast, are associated with lower diversification rates.


Subject(s)
Annonaceae/classification , Annonaceae/genetics , Biodiversity , Genome, Plant , Phylogeny , Plastids/genetics
2.
Compend Contin Educ Dent ; 18(5): 430-3, 436, 438 passim, 1997 May.
Article in English | MEDLINE | ID: mdl-9533356

ABSTRACT

Uncontrollable disruptive gagging makes most dental procedures impossible to perform. Well-intentioned interventions by dentists often fail because of the inability to differentiate between psychogenic disruptive gagging and disruptive gagging of somatic origin. To help the clinician differentiate the diagnosis and management of somatogenic disruptive gagging from the psychogenic form, a review of the pertinent literature, diagnostic criteria, treatment recommendations, and a clinical case of psychogenic disruptive gagging are presented.


Subject(s)
Dental Anxiety/psychology , Dental Impression Technique/adverse effects , Gagging , Psychophysiologic Disorders , Humans , Male , Middle Aged , Psychophysiologic Disorders/diagnosis , Psychophysiologic Disorders/therapy , Reflex , Relaxation Therapy
3.
Poult Sci ; 67(8): 1166-73, 1988 Aug.
Article in English | MEDLINE | ID: mdl-3217305

ABSTRACT

The nutritional value of raw and autoclaved grain amaranth, its milling fractions (perisperm and bran), fat-free flour, and of popped amaranth was evaluated for growing chickens. The control diet, which was composed primarily of corn and soybean meal, contained 3.06 kcal apparent ME (AME)/g and 23.6% CP. Test diets contained about the same AME and CP levels, and the following levels of the test samples: whole grain amaranth flour, 61.46%; fat-free flour, 62.10%; perisperm, 49.50%; bran, 35.30%; and popped amaranth, 61.10%. Two groups of six unsexed broiler chicks each, 2-day old when received, were used per diet. Chickens fed diets containing autoclaved grain amaranth or its fractions over 17 or 18 days grew as well as those fed the control diet. Feeding of popped amaranth resulted in poorer performance. On a dry matter basis, AME values of raw grain amaranth flour, fat-free flour, perisperm, bran, and popped amaranth were found to be 3.21, 3.09, 3.68, 3.06, and 2.98 kcal/g, respectively. Respective AME values for the first four autoclaved samples were 3.04, 2.94, 3.10, and 3.17 kcal/g. Autoclaved grain amaranth and its perisperm fraction replaced corn in the diets of growing chickens with similar performance results.


Subject(s)
Animal Feed , Azo Compounds , Body Weight , Chickens/growth & development , Edible Grain , Animals , Nutritive Value
4.
Poult Sci ; 66(3): 493-9, 1987 Mar.
Article in English | MEDLINE | ID: mdl-3601860

ABSTRACT

Rice bran either raw or processed in an extrusion cooker at 130 C was fed to meat strain chickens for 25 days after hatch. Either full fat or hexane-extracted rice bran was placed in the diet at the equivalent of 60% full fat bran. Raw full fat bran for one diet was stored at -23 C until fed, whereas rice bran for all other diets was stored at 32 C. Four experiments were conducted at 6-week intervals. Free fatty acid (FFA) content in oil from raw rice bran stored at the elevated temperature reached 81% by the start of the final experiment whereas FFA in stabilized bran oil remained at about 3%. Chickens fed stabilized rice bran made significantly greater gains than chickens fed raw bran diets. Feed efficiency was superior for chickens fed either full fat or extracted stabilized bran compared with full fat bran stored at either 32 or -23 C. Feed conversion for extracted raw bran was intermediate between stabilized bran and full fat raw bran. Raw bran stored at 32 C (with elevated FFA content) tended to produce lower gains than the frozen raw bran. Analysis of the combined data from all four trials indicated that raw bran held at 32 C produced the lowest gains among all of the diets.


Subject(s)
Animal Feed , Chickens/growth & development , Oryza , Animals , Body Weight , Male , Nutritive Value
5.
S Afr Med J ; 69(2): 103-6, 1986 Jan 18.
Article in English | MEDLINE | ID: mdl-2417339

ABSTRACT

The effects of free and liposome-encapsulated bleomycin and adriamycin on a human hepatocellular carcinoma cell line were studied in vitro. Free and encapsulated bleomycin inhibited cell growth over 24 hours by the same amount, but DNA synthesis was inhibited more by the encapsulated form. Twenty-five per cent of the cell population showed drug resistance to the free drug, whereas this decreased to 17% with encapsulated bleomycin. These results suggest that the cell membrane plays a role in bleomycin resistance, and that cell death is not solely due to inhibition of DNA synthesis. Encapsulated adriamycin inhibited cell growth and DNA synthesis by the same amount or less than the free drug. Possible explanations are that adriamycin exerts its main cytotoxic action by interacting with the cell surface, or that at the low concentrations used, free drug is taken up more efficiently than the encapsulated drug. Liposomes as drug carriers constitute a useful system for studying the basic mechanisms involved in drug action and in particular the role played by cell membranes.


Subject(s)
Bleomycin/pharmacology , Cell Membrane/drug effects , Doxorubicin/pharmacology , Liposomes/metabolism , Bleomycin/metabolism , Carcinoma, Hepatocellular , Cell Division/drug effects , Cell Line , Cell Membrane/metabolism , Cell Membrane Permeability , Cell Survival/drug effects , DNA, Neoplasm/biosynthesis , Doxorubicin/metabolism , Drug Resistance , Humans , Liver Neoplasms
9.
Am J Clin Nutr ; 32(6): 1188-91, 1979 Jun.
Article in English | MEDLINE | ID: mdl-312597

ABSTRACT

The in vivo dietary fiber contents of wheat milling fractions and wheat foods, determined in rat feeding experiments, were compared with dietary fiber values determined in vitro with pronase alpha-amylase digestion. Both types of dietary fiber values were compared with crude fiber and neutral detergent fiber values in the same materials. Regression analyses indicated close correlation amongst all values determined. It appears that laboratory analysis for crude fiber, neutral detergent fiber, or in vitro dietary fiber accurately predicts in vivo dietary fiber (rats) for wheat milling fractions when the laboratory result is adjusted by means of an appropriate regression equation.


Subject(s)
Cellulose/analysis , Dietary Fiber/analysis , Polysaccharides/analysis , Triticum/analysis , Animals , Biological Assay , Bread/analysis , Detergents , Flour/analysis , Food Handling , Pronase , Rats , Regression Analysis , alpha-Amylases
11.
Am J Clin Nutr ; 31(12): 2136-9, 1978 Dec.
Article in English | MEDLINE | ID: mdl-727160

ABSTRACT

Rat feeding studies were used to measure the dietary fiber content of wheat milling fractions, white and whole wheat breads, and wheat-based breakfast foods. Straight line correlations were established for the relationships between dietary fiber (y) and crude fiber (x) where y = 4.17x--0.27 (r = 0.997, P less than 0.01). Dietary fiber values ranged from 1.1% (flour) to 53.4% (bran), dry weight basis.


Subject(s)
Cellulose/analysis , Dietary Fiber/analysis , Digestion , Triticum , Animals , Bread , Edible Grain , Food Handling , Rats
12.
S Afr Med J ; 53(6): 204-8, 1978 Feb 11.
Article in English | MEDLINE | ID: mdl-77562

ABSTRACT

A dose of 10 microgram/ml bleomycin inhibited the growth of oesophageal carcinoma cells and non-squamous cells in vitro. Drug concentration, density of cells and the time of exposure to the drug were important variables. The oesophagus cancer cells increased in volume by 2,5 +/- 0,2% per hour until the onset of lysis at 96 hours. The effects of the drug were irreversible even when the exposure time was only 24 hours. A certain proportion of the cell population was resistant to bleomycin and these cells remained resistant when the drug was removed for 48 hours and then replaced. No drug inactivation or uptake could be detected with the use of microbiological assay after 4 days of incubation with 3 cell types. There is poor correlation between in vitro and in vivo results.


Subject(s)
Bleomycin/pharmacology , Carcinoma, Squamous Cell , Esophageal Neoplasms , Cell Count , Cell Division/drug effects , Cell Line , Cell Survival/drug effects , Depression, Chemical , Humans , In Vitro Techniques
16.
Proc Natl Acad Sci U S A ; 71(1): 26-9, 1974 Jan.
Article in English | MEDLINE | ID: mdl-4521055

ABSTRACT

Cell fusion between opposite mating types 5 and 21 of the yeast Hansenula wingei is initiated by a strong sexual agglutination reaction. The mating factors responsible for the specificity of cellular recognition are complementary glycoproteins which form a physical complex in vitro. The complex is assayed by recovery of agglutination activity of the multivalent 5-factor after the univalent 21-factor has been inactivated by treatment of the complex with alkali. The 5-factor.21-factor complex, purified on Sepharose 6B, is large (several million daltons) and heterogeneous. The three peaks of 5-factor activity contain a number of combining sites proportional to molecular size.


Subject(s)
Fungal Proteins/physiology , Glycoproteins/physiology , Reproduction , Yeasts/physiology , Binding Sites , Cell Adhesion , Cell Fusion , Chromatography, Gel , Fungal Proteins/analysis , Fungal Proteins/metabolism , Glycoproteins/analysis , Glycoproteins/metabolism , Molecular Weight , Yeasts/cytology
20.
J Am Chem Soc ; 88(16): 3844-7, 1966 Aug 20.
Article in English | MEDLINE | ID: mdl-5916374
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