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1.
J Plant Res ; 137(5): 829-845, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39009902

ABSTRACT

Dipcadi (Scilloideae: Asparagaceae) is a genus of bulbous monocots with approximately 40 species, of which 13 occur in India. Species delimitation within the genus has been troublesome hindering a comprehensive phylogenetic analysis. The most recent phylogeny of the subfamily Ornithogaloideae included six species of Dipcadi only from Africa. Here, we reconstructed the phylogeny of Ornithogaloideae including 23 accessions comprising 13 recognized taxa (11 species and two varieties) of Indian Dipcadi. The phylogenetic analyses were based on nucleotide sequences of three plastid regions (rbcL, matK and trnL-F spacer) and one nuclear region (ITS). Pseudogaltonia clavata exhibited sister relationship to Dipcadi. Our combined nuclear + plastid dataset analyses revealed a monophyletic Dipcadi with five clades, Clade I-V. Clade I, II and III included mainly Indian species whereas Clade V included mostly African species. Clade IV comprised D. serotinum. Clade I included nine taxa including our newly described species, D. mukaianum. The new species was phylogenetically placed with D. erythraeum, D. saxorum and D. ursulae. Morphologically, the species resembled D. montanum and D. ursulae but differed in characters such as tepal cohesion, number of ovules per locule and foul-smelling flowers. Clade II and III included 11 and six taxa, respectively. D. erythraeum which has a native range from Egypt to western India was found in Clades I and V. The widespread Dipcadi species, viz. D. erythraeum and D. serotinum showed polyphyly however, the monophyly of Dipcadi is established. Our studies suggest that additional molecular markers (plastid as well as nuclear) should be tested for their taxonomy utility. Further work on the historical biogeography of Dipcadi on the subfamily Ornithogaloideae with more genetic data will yield insights how aridification of the landscape would have shaped the evolution of the geographical clades.


Subject(s)
Asparagaceae , Phylogeny , India , Asparagaceae/genetics , Asparagaceae/classification , Plastids/genetics , DNA, Plant/genetics , Sequence Analysis, DNA
2.
Des Monomers Polym ; 23(1): 93-105, 2020 Jul 26.
Article in English | MEDLINE | ID: mdl-33029078

ABSTRACT

A new aromatic diacid (II) was synthesized and Characterized by Spectroscopic techniques namely, FT-IR, 1 H and 13 C NMR, etc. A series of aromatic aliphatic polyamides containing phenoxy s-triazine ring with methylene spacer group was synthesized from diacid (II) and various aromatic diamines by using Yamazaki Phosphorylation method. These polyamides were obtained in good yields and characterized by solubility in common organic solvent, inherent viscosity, FT-IR, X-ray diffraction analysis. All of these polyamides were found to be amorphous in morphology as indicated by XRD to posses outstanding solubilities, and to be easily dissolved in amide-type polar aprotic polar solvents. Polyamides with moderate inherent viscosity in the range 0.21 to 0.41 dL/g in N,N,dimethyl formamide solvent (DMF) at 30 ± 0.1° C. The Thermal properties of the polyamides were evaluated by Thermogravimetric analysis and Differential scanning calorimetery. These polymer shows good thermal stability with glass transition temperature (Tg) of 143-223°C and their (Tmax) weight loss temperature were around 426-455°C, confirming their good thermal stability. The char yields of these polymers were given their limiting oxygen index LOI 32.3 to 37.5 5% values of polyamides; indicate these polymers also show good flame resistance. The NPs were negatively charged with a zeta potential of -24.2 to -37.9 mV indicating a good colloidal stability against aggregation.

3.
Biochim Biophys Acta ; 750(2): 404-10, 1983 Feb 07.
Article in English | MEDLINE | ID: mdl-6860691

ABSTRACT

Studies have been conducted on the uptake and metabolism of unesterified oleic acid and lipoprotein triacylglycerol by the perfused rat heart, and of oleic acid, free glycerol and lipoprotein triacylglycerol by rat cardiac myocytes. The perfused heart efficiently extracted and metabolized unesterified fatty acid and the fatty acid released during lipolysis of the recirculating triacylglycerol. The released glyceride glycerol, however, was largely accumulated in the perfusion media. Cardiac myocytes also extracted and rapidly metabolized unesterified fatty acid. As with the intact heart, free glycerol was poorly utilized by cardiac myocytes. Although the cells appeared to extract a small amount of available extracellular triacylglycerol presented as very low density lipoprotein, this was shown to be unmetabolized, suggesting adsorption rather than surface lipolysis and uptake of the released fatty acid. The data suggest that myocytes are unable to metabolize triacylglycerol fatty acids without prior lipolysis by extracellular (capillary endothelial) lipoprotein lipase.


Subject(s)
Lipoproteins, VLDL/metabolism , Myocardium/metabolism , Oleic Acids/metabolism , Triglycerides/metabolism , Animals , Carbon Radioisotopes , Heart Ventricles/metabolism , In Vitro Techniques , Lipolysis , Male , Oleic Acid , Perfusion , Rats , Rats, Inbred Strains
4.
Biochim Biophys Acta ; 620(1): 63-9, 1980 Oct 06.
Article in English | MEDLINE | ID: mdl-7417481

ABSTRACT

Cardiocytes were prepared by enzymatic dissociation of adult rat ventricular tissue, and comparative studies on lipoprotein lipase activity were conducted on fresh homogenates and acetone powders of these cells. Lipolytic activity in fresh homogenates was largely dependent on addition of serum activator to the assay, and the activity was sensitive to 1 M NaCl. Lipoprotein lipase activity was maximized in acetone powder preparations of cardiocytes. Approx. 10% of the total lipolytic activity was extractable from acetone powders of cells homogenized in the absence of serum, while approx. 50% was soluble from powders of cells homogenized with 10% serum. The non-extractable lipolytic activity was inhibited 80% with 1 M NaCl and about 47% with antibodies (IgG) to heart lipoprotein lipase. The buffer-extracted enzyme was completely sensitive to NaCl and was inhibited 80% by low concentrations of anti-lipoprotein lipase antibodies.


Subject(s)
Lipoprotein Lipase/metabolism , Myocardium/enzymology , Animals , Heart/drug effects , Heparin/pharmacology , Immunoglobulin G/pharmacology , Male , Rats , Sodium Chloride/pharmacology
5.
Arch Ophthalmol ; 108(1): 128-32, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2288550

ABSTRACT

We have estimated the incidence of retinoblastoma in the United States from data available form the Surveillance, Epidemiology, and End Results program of the National Cancer Institute, Bethesda, Md (1974 through 1985). The larger number of cases available (220) compared with those of previous US population-based studies enabled us to evaluate change in incidence over time and to more precisely estimate incidence according to various demographic characteristics. The incidence of retinoblastoma has been almost uniform form 1974 to 1985. The average annual incidence of retinoblastoma was 5.8 per million for children younger than 10 years and 10.9 per million for children younger than 5 years. There was no difference in the incidence of retinoblastoma by either sex or race. The overall 5-year cumulative survival rate was 91% (95% confidence interval, 87% to 95%). The data indicate a worsening survival with increasing age at diagnosis, through age 2 years, but a less clear relationship of survival with diagnosis beyond age 2 years.


Subject(s)
Eye Neoplasms/epidemiology , Retinoblastoma/epidemiology , Age Factors , Black People , Child , Child, Preschool , Cohort Studies , Demography , Eye Neoplasms/mortality , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Male , Prognosis , Retinoblastoma/mortality , Sex Factors , Survival Rate , United States/epidemiology , White People
6.
Arch Ophthalmol ; 112(10): 1349-55, 1994 Oct.
Article in English | MEDLINE | ID: mdl-7945039

ABSTRACT

OBJECTIVE: To identify risk factors associated with the two major types of strabismus--esotropia and exotropia--in a cohort of children followed up from gestation to age 7 years. DESIGN: Pregnant women were enrolled in the Collaborative Project of the National Institute of Neurological Disorders and Stroke, Bethesda, Md, from 1959 to 1965 at 12 university centers. This large multidisciplinary study was designed to evaluate the developmental consequences of complications during pregnancy and the perinatal period. Data on maternal, socioeconomic, perinatal, and neonatal characteristics were collected from 39,227 children and their mothers by medical examination and interview. Examinations of the children were performed at birth, 4 months, 8 months, 1 year, and 7 years. OUTCOME MEASURES: The evaluation of the presence of strabismus was performed during follow-up examinations and confirmed at the 7-year follow-up visit. Potential risk factors for strabismus were evaluated from the maternal, socioeconomic, perinatal, and neonatal characteristics. RESULTS: Esotropia developed in 1187 children (3.0%), and exotropia developed in 490 children (1.2%). Esotropia was more common in whites (3.9% in whites vs 2.2% in blacks, P < .0001). The occurrence of exotropia was similar in the two races (1.2% in whites and 1.3% in blacks). Results of multivariable logistic regression models showed that the risk of strabismus increased with low birth weight (P < .0001). For infants weighing 1500 g at birth compared with those weighing 4000 g at birth, the odd ratios were 3.26 (95% confidence interval, 2.50 to 4.25) for esotropia and 4.01 (95% confidence interval, 2.77 to 5.80) for exotropia. Maternal cigarette smoking during pregnancy also increased the risk of each type of strabismus (P < .0001). For offspring of mothers who smoked more than two packs of cigarettes per day compared with those whose mothers did not smoke, the odds ratios were 1.83 (95% confidence interval, 1.51 to 2.22) for esotropia and 2.32 (95% confidence interval, 1.72 to 3.13) for exotropia. Maternal age was also a significant risk factor for esotropia (P = .0005). The risk of esotropia increased with increasing age until age 34 years. In particular, the odds ratio for mothers aged 30 to 34 years relative to that for mothers aged 20 to 24 years was 1.43 (95% confidence interval, 1.19 to 1.70). CONCLUSIONS: Esotropia was more common in whites than in blacks. The occurrence of exotropia was similar in the two races. Maternal cigarette smoking during pregnancy and low birth weight were independent and important risk factors for both esotropia and exotropia. There was an increased risk of esotropia with increasing maternal age.


Subject(s)
Esotropia/etiology , Exotropia/etiology , Adult , Black People , Child , Esotropia/ethnology , Exotropia/ethnology , Female , Humans , Infant, Low Birth Weight , Infant, Newborn , Male , Maternal Age , Prevalence , Risk Factors , Smoking , United States/epidemiology , White People
7.
Lipids ; 18(11): 808-13, 1983 Nov.
Article in English | MEDLINE | ID: mdl-6656537

ABSTRACT

Studies have been conducted on the uptake and metabolism of unesterified fatty acid, free glycerol and 1-hexadecyl glyceryl ether by rat cardiac myocytes, and of fatty acid, intact triglyceride and the glyceryl ether by perfused rat hearts. Cardiac myocytes efficiently extracted, oxidized and esterified oleic acid, but demonstrated little ability to utilize free glycerol. Although the glyceryl ether was efficiently extracted by myocytes, it was neither hydrolyzed or esterified. The perfused heart also extracted and metabolized unesterified fatty acid, and the fatty acid released during lipolysis of circulating lipoprotein triglyceride. The glyceride glycerol, however, was largely recovered (90%) in the perfusate suggesting inefficient myocardial utilization of either free glycerol or partial glycerides. Myocardial extraction of glyceryl monoether was demonstrated, but the monoglyceride analogue was also unmetabolized by intact heart tissue. The results suggest that if monoglycerides are produced by the action of lipoprotein lipase on circulating triglycerides, reutilization of intact monoglycerides for higher glyceride synthesis is not a major fate of these products.


Subject(s)
Fatty Acids/metabolism , Glycerol/analogs & derivatives , Glycerol/metabolism , Glyceryl Ethers , Myocardium/metabolism , Animals , Lipoproteins, VLDL/metabolism , Male , Myocardium/cytology , Perfusion , Rats , Triglycerides/metabolism
8.
Basic Res Cardiol ; 80 Suppl 2: 45-9, 1985.
Article in English | MEDLINE | ID: mdl-4062836

ABSTRACT

Canine and rat cardiac myocytes, prepared by proteolytic disaggregation, retain morphological and topographical features of intact tissue. Cells are rod-shaped and are cleanly separated at their sarcolemmal and intercalated disc borders. Cells demonstrate glucose and fatty acid uptake and metabolic features comparable to intact organ, and are responsive to insulin and epinephrine, but nor carnitine. Although rat cardiac cells contain immunodetectable lipoprotein lipase, they are incapable of metabolizing extracellular lipoprotein triglyceride, nor the glycerol or monoglyceride moieties of the triglyceride. These and other metabolic characteristics suggest that cardiac cells can provide a useful cellular model for studies on cardiac pathophysiology.


Subject(s)
Myocardium/ultrastructure , Sarcolemma/ultrastructure , Animals , Cell Separation , Dogs , Intercellular Junctions/physiology , Intercellular Junctions/ultrastructure , Microscopy, Electron, Scanning , Myocardial Contraction , Myocardium/enzymology , Myocardium/metabolism , Rats , Sarcolemma/physiology
9.
Scan Electron Microsc ; (3): 375-88, 1979.
Article in English | MEDLINE | ID: mdl-524009

ABSTRACT

We have previously described detailed procedures for isolating rat and canine myocytes from adult ventricular tissue, and have investigated ultrastructural and functional properties of these cells. The effects of isolation on cell morphology were tested by comparative scanning (SEM) and transmission electron microscopy (TEM) of adult canine cardiac myocytes. Cells cleanly separated at the lateral sarcolemmal borders and at the intercalated discs. Since the cells were contracted during fixation, SEM of the lateral cell borders showed longitudinal folds and transverse ridges. There were rows of regular protrusions corresponding to the mitochondria immediately beneath the sarcolemmal surface. Openings in the sarcolemmal membrane occurred at regular intervals at the level of the Z-bands and may represent the sites of externalization of the transverse tubular system. By SEM, the intercalated disc junction appeared as a microvillar border and this corresponded directly to the scalloped appearance seen by TEM. A controlled sonication procedure was developed to allow specific removal of the sarcolemma without disruption of underlying organelles. This allowed visualization of the cellular organization of myofibrils, mitochondria and the transverse tubular system. These cells retain biochemical and enzymatic characteristics of adult dog cardiac tissues such as ouabain and insulin sensitivity, fatty acid and lipoprotein uptake and metabolism, and prostaglandin synthesis. This cytological preparation permits the correlation of these types of metabolic studies with the known functions of isolated subcellular organelles of the myocardium.


Subject(s)
Myocardium/cytology , Myocardium/metabolism , Animals , Cells, Cultured , Dogs , Fatty Acids, Nonesterified/metabolism , Glucose/metabolism , Lipoprotein Lipase/metabolism , Lipoproteins/metabolism , Microscopy, Electron , Myocardial Contraction/drug effects , Ouabain/pharmacology , Prostaglandins/biosynthesis , Rats , Triglycerides/metabolism
11.
Prev Med ; 23(5): 733-4, 1994 Sep.
Article in English | MEDLINE | ID: mdl-7845949
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