Nucleotypic influences on chromosome-specific chiasma variation in Crepis capillaris. I. Responses to early colchicine treatment and chromosome doubling

Genome ◽  
1996 ◽  
Vol 39 (6) ◽  
pp. 1078-1085 ◽  
Author(s):  
M. T. Abberton ◽  
R. S. Callow
Keyword(s):  
Key Words ◽  
Chiasma Frequency ◽  
Chromosome Doubling ◽  
Colchicine Treatment ◽  
Seedling Stage ◽  
Published Data ◽  
Crepis Capillaris ◽  
The Mean ◽  
Diploid Level ◽  
Multiplicative Effects

Additive and multiplicative effects of colchicine treatment at the seedling stage and of chromosome doubling on chromosome-specific chiasma frequency at metaphase I have been measured in comparisons between C0 and untreated diploids and between C0 autotetraploids and C0 diploids. Early colchicine treatment increases the frequency of chromosome C univalents to 1.8% but has no similar effect on chromosomes A and D. Colchicine treatment has little net effect on mean chiasma frequency, deducting an average of 0.204 chiasmata per set but otherwise multiplying the mean by a factor of 1.182. These additive and multiplicative effects represent averages of six phenotypes. Chromosome doubling in a tetraploid–diploid chimaera subtracts an average of 0.265 chiasmata per set but otherwise doubles the numbers of chiasmata at the diploid level (× 2.134). Comparison of six diploids and tetraploids reveals modest average additive (+ 1.103) and multiplicative effects (× 1.190). The implications of these findings are discussed in the light of new analyses of previously published data. Key words : chiasmata, Crepis, colchicine, meiosis, polyploidy.

Meiotic variation in an intergenomic autopolyploid series. I. Chiasma frequency

Genome ◽  
1995 ◽  
Vol 38 (1) ◽  
pp. 122-132 ◽  
Author(s):  
A. J. Wallace ◽  
R. S. Callow
Keyword(s):  
Genome Size ◽  
Chiasma Frequency ◽  
Chromosome Doubling ◽  
Cellular Component ◽  
Absolute Size ◽  
Interspecific Differences ◽  
Threefold Increase ◽  
Multiplicative Effect ◽  
The Absolute ◽  
Diploid Level

Variation in chiasma frequency has been studied in PMCs of diploids and C0 autotetraploids of seven Lathyrus species exhibiting a range of genome size (10.8–19.9 pg DNA/2C). Variation in chiasma frequency showed no relation to changes in genome size, either between species or between disomic sets within nuclei. Mean chiasma frequency of the tetraploids showed a 75% increase over that in the diploids. Half of this increase represents an additive effect of chromosome doubling. Total variance in chiasma frequency of autotetraploids increases by 80% over that in diploids, in line with the square of the multiplicative effect of chromosome doubling. At the diploid level, interspecific differences account for the major component of variance (63.1%). Phenotypic variation in chiasma frequency was apparent in all seven species but represented the smallest component of variance (2.8%). Chromosome doubling results in an eightfold increase in the absolute size of the phenotypic component of variance in chiasma frequency and a threefold increase in that of the cellular component. It has no effect on the absolute size of the interspecific component.Key words: meiosis, chiasma frequency, autopolyploid, Lathyrus.

KNOWLEDGE, ATTITUDE AND PRACTICES OF CARETAKERS AND HEALTH PROFESSIONALS TOWARD TEETHING IN INFANTS

2011 ◽  
pp. 52-59
Author(s):  
Binh Bao Son Bui
Keyword(s):  
Sleep Disturbance ◽  
Key Words ◽  
Breast Feeding ◽  
Health Professionals ◽  
Feeding Problems ◽  
Central Hospital ◽  
Pediatric Department ◽  
Correct Knowledge ◽  
The Mean

Objective and methods: a prospective questionnaire based study on 71 parents (caretakers) of consecutive children treated at the Pediatric Department, Hue Central Hospital and on 47 health professionals at the department was conducted from September until December 2009 to investigate the knowledge, attitude and practices of the caretakers, nurses and postgraduated doctors toward teething in infants. Results: Most responders believed that teething causes fever, irritability, feeding problems, drooling, biting, sleep disturbance, swollen gums, crying, lose of appetite for solids; and fever over 38oC was also believed to be associated with teething. The mean eruption time of the first tooth was from 6 months. Most caretakers had normal attitude to manifestations ascribed to teething (54.9%). The most common management to symptoms attributed to teething included increased breast-feeding, oral paracetamol, increased fluid supplying and physician consulting. Conclusion: Correct knowledge to teething in infants need to be educated for parents (caretakers) and even for health professionals. Key words: knowledge, attitude, practices, teething, infants.

CLINICAL CHARACTERISTICS OF THE CHRONIC DACRYOCYSTITIS AND THE SUCCESS RATE OF EXTERNAL DACRYOCYSTORHINOSTOMY

2015 ◽  
pp. 29-34
Author(s):  
Van Nam Phan ◽  
Ba Kien Tran
Keyword(s):  
Success Rate ◽  
Key Words ◽  
Clinical Characteristics ◽  
Lacrimal Duct ◽  
Interventional Study ◽  
Chronic Dacryocystitis ◽  
External Dacryocystorhinostomy ◽  
The Mean

Purpose: To determine the clinical characteristics of the chronic dacryocystitis and the success rate of external dacryocystorhinostomy. Methods: The retrospective, interventional study without comparing on 27 patients (32 eyes) of chronic dacryocystitis who underwent dacryocystorhinostomy (DCR) from 2010 to 2011. Results were evaluated with standards: epiphora, purelence, lacrimal duct irrigation. Results: Over period of 6 months, 27 patients including 25 (92.59%) female, 2 (7.41%) male. The mean age was 49.8 years (range, 22-79 years). All patients demonstrated epiphera (range, 3 months – 11 years). Dacryocystorhinostomy was performed unilaterally in 81.48%, bilateral 18.52%. Successrate was 90.06% overall. Conclusions: Although techniques in dacryocystorhinostomy of DUPUY-DUTEMPS is old, its result is mainstay of treatment for chronic dacryocystitis in Vietnam. Key words: Dupuy-Dutemps, chronic dacryocystitis

RESULTS OF INTRALESIONAL TRIAMCINOLONE ACETONIDE FOR CHALAZION TREATMENT

2011 ◽  
pp. 100-104
Author(s):  
Thi Thu Nguyen ◽  
Viet Hien Vo ◽  
Thi Em Do
Keyword(s):  
Success Rate ◽  
Key Words ◽  
Triamcinolone Acetonide ◽  
Lower Eyelid ◽  
Upper Eyelid ◽  
Interventional Trial ◽  
The Mean ◽  
First Time

The study use intralesional triamcinolone acetonide injection proceduce for chalazion treatment.1. Objectives: To evaluate results of intralesional triamcinolone acetonide injection for chalazion treatment. 2. Method: This noncomparative prospective interventional trial included 72 chalazions of 61 patients. 3. Results: 61 patients (72 chalazions) with 19 males (31.1%) và 42 females (68.9%), the mean age was 24 ± 9,78 years. 31.1% patients was the first time chalazion and 68.9% patients was more than one times chalazion including 78.6% patients was recurrent at the first position and 21.4% patients occur at new position. 72 chalazions with 16 (22.2%) chalazions was treated before and 56 (77.8%) chalazions wasn’t done that. 72 chalazions with 49 chalazions (68.1%) are local in upper eyelid and 23 chalazions (31.9%) are local in lower eyelid. The mean of chalazion diameter is 6.99 ± 3.03mm. Intralesional triamcinolone acetonide is injected to treat 72 chalazions with 16 (22.2%) chalazions are injected through the route of skin and 56 (77.8%) chalazions are injected through the route of conjunctiva. After 2 weeks follow-up, the success rate was 93.1% and 6.9% failed. 4. Conclusion: intralesional triamcinolone acetonide injection for chalazion treatment is really effective. Key words: chalazion, intralesional triamcinolone acetonide.

Multiplicative vs. arbitrary gene action in heterosis.

Genetics ◽  
1992 ◽  
Vol 131 (2) ◽  
pp. 461-469 ◽  
Author(s):  
F W Schnell ◽  
C C Cockerham
Keyword(s):  
Gene Action ◽  
Extensive Literature ◽  
Additive Effects ◽  
Nonlinear Functions ◽  
Epistatic Effects ◽  
Genetic Significance ◽  
The Mean ◽  
The Difference ◽  
Multiplicative Models ◽  
Multiplicative Effects

Abstract In this article we investigate multiplicative effects between genes in relation to heterosis. The extensive literature on heterosis due to multiplicative effects between characters is reviewed, as is earlier work on the genetic description of heterosis. A two-locus diallelic model of arbitrary gene action is used to derive linear parameters for two multiplicative models. With multiplicative action between loci, epistatic effects are nonlinear functions of one-locus effects and the mean. With completely multiplicative action, the mean and additive effects form similar restrictions for all the rest of the effects. Extensions to more than two loci are indicated. The linear parameters of various models are then used to describe heterosis, which is taken as the difference between respective averages of a cross (F1) and its two parent populations (P). The difference (F2 - P) is also discussed. Two parts of heterosis are distinguished: part I arising from dominance, and part II due to additive x additive (a x a)-epistasis. Heterosis with multiplicative action between loci implies multiplicative accumulation of heterosis present at individual loci in part I, in addition to multiplicative (a x a)-interaction in part II. Heterosis with completely multiplicative action can only be negative (i.e., the F1 values must be less than the midparent), but the difference (F2 - P) can be positive under certain conditions. Heterosis without dominance can arise from multiplicative as well as any other nonadditive action between loci, as is exemplified by diminishing return interaction. The discussion enlarges the scope in various directions: the genetic significance of multiplicative models is considered.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Hybrid Triploid Induced by Megaspore Chromosome Doubling in Jujube (Ziziphus jujuba Mill.) ‘Maya’ and Its Characteristics

Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 112
Author(s):  
Songshan Liu ◽  
Chenxing Zhang ◽  
Weicong Yang ◽  
Xiang Li ◽  
Lu Hou ◽  
...  
Keyword(s):  
Chromosome Doubling ◽  
Colchicine Treatment ◽  
Fruit Trees ◽  
Growth Stress ◽  
Optimal Timing ◽  
Photosynthetic Parameters ◽  
Flower Bud ◽  
Treatment Methods ◽  
Triploid Individual ◽  
Colchicine Solution

Polyploid breeding is an important strategy for tree improvement because polyploid individuals typically show superior traits, such as improved growth, stress resistance, and superior fruit quality. Artificial induction of chromosome doubling of female gametes is an effective approach to obtain triploid progeny. However, no triploid fruit tree cultivars have been developed using this approach. The objective of this study was to explore the utility of chromosome doubling in female gametes of ‘Maya’ jujube to produce triploid individuals. The temporal relationship between flower bud morphology and the megaspore meiotic stage was studied to guide the optimal timing of colchicine treatment. Colchicine solution was applied to bearing shoots of mature ‘Maya’ jujube trees in a field experiment using two treatment methods (improved cotton leaching and injection method) and three concentrations (0.3%, 0.4%, and 0.5%). The water transport rate of ‘Maya’ jujube shoots was studied using dye solution to judge the effectiveness and timing of the colchicine treatment methods. Two triploids were identified among the progenies from the colchicine-treated shoots. The highest efficiency of triploid production was 3.3% when flower buds of diameter 1.76–2.12 mm were treated with 0.3% colchicine solution for 4 h using an improved cotton leaching method. The ground diameter, plant thorn length, leaf width, leaf area, stomatal length, stomatal width, chlorophyll content, and photosynthetic parameters of one triploid individual were significantly higher than those of diploids of identical parentage at 18 months old. Thus, induction of 2n megaspores is an effective approach to generate triploid jujube. These results are expected to promote and accelerate triploid breeding in fruit trees.

scholarly journals Population density of helminths in ducks: effects of host’s age, sex, breed and season

1970 ◽  
Vol 6 (1) ◽  
pp. 45-51 ◽  
Author(s):  
T Farjana ◽  
KR Islam ◽  
MMH Mondal
Keyword(s):  
Population Density ◽  
Key Words ◽  
Parasitic Infection ◽  
Winter Season ◽  
Helminth Parasites ◽  
Domestic Ducks ◽  
The Mean

 A study was conducted to investigate the population density of helminth parasites in domestic ducks (Anas boschas domesticus) in relation to host's age, sex, breed and seasons of the year from March 2002 to May 2003. A total of 300 ducks were collected from different villages of Netrokona and Mymensingh districts of Bangladesh and autopsied to collect the parasites and counted to determine the population density of parasites. Off 300 ducks examined, 290 (96.66%) were infected with 17 species of helminth parasites in which 11 species were trematodes, 4 were cestodes and 2 nematodes. Among the parasites, density of cestodes was the highest (33.15±5.26), followed by trematodes (5.98±1.32); and nematodes (2.95±0.68). Mean density of parasites increased with the increase of age (young: 21.23±1.09, adult: 26.18±2.14 and old: 27.87±2.98) while the mean density of most of the helminth parasites was higher in female ducks (31.35±4.72) than in males (27.52±3.32). Indigenous ducks (33.72±3.61) were infected with the highest load of helminths than Khaki Campbell breed (29.61±4.32) of ducks. Mean density of most trematodes (5.42±0.80) were highest in winter season whereas mean density of all cestodes (48.43±4.85) and nematodes (4.13±1.76) were highest in summer.  The present study suggests that age, sex, breed of ducks and seasons of the year influence the parasitic infection to a greater extend. Key words: Population density, helminths, duck, Bangladesh DOI = 10.3329/bjvm.v6i1.1338 Bangl. J. Vet. Med. (2008). 6 (1): 45-51

Putative diploid ancestors of 80-chromosome Glycine tabacina

Genome ◽  
1992 ◽  
Vol 35 (1) ◽  
pp. 140-146 ◽  
Author(s):  
R. J. Singh ◽  
K. P. Kollipara ◽  
F. Ahmad ◽  
T. Hymowitz
Keyword(s):  
Adventitious Roots ◽  
Chromosome Doubling ◽  
Colchicine Treatment ◽  
Meiotic Pairing ◽  
B Genome ◽  
Specific Hybridization ◽  
A Genome ◽  
Genome Homology ◽  
Glycine Tabacina ◽  
Natural Mutation

The objective of this study was to discover the diploid progenitors of 80-chromosome Glycine tabacina with adventitious roots (WAR) and no adventitious roots (NAR). Three synthetic amphiploids were obtained by somatic chromosome doubling. These were (i) (G. latifolia, 2n = 40, genome B1B1,) × (G. microphylla, 2n = 40, genome BB) = F1(2n = 40, genome BB1) – 0.1% colchicine treatment (CT) – 2n = 80, genome BBB1B1; (ii) (G. canescens, 2n = 40, genome AA) × G. microphylla, 2n = 40, genome BB) = F1 (2n = 40, genome AB) – (CT) – 2n = 80, genome AABB; (iii) (G. latifolia, 2n = 40, B1B1) × G. canescens, 2n = 40, AA) = F1 (2n = 40, genome AB1) – (CT) – 2n = 80, genome AAB1B1. The segmental allotetraploid BBB1B1 was morphologically similar to the 80-chromosome G. tabacina (WAR), but meiotic pairing data in F1 hybrids did not support the complete genomic affinity. Despite normal diploid-like meiosis in allotetraploids AABB and AAB1B1, AABB was completely fertile, while pod set in AAB1B1 was very sparse. Morphologically, allotetraploid AABB was indistinguishable from the 80-chromosome G. tabacina (NAR) but in their F1 hybrids, the range of univalents at metaphase I was wide (4–44). The allotetraploid AAB1B1 did not morphologically resemble the 80-chromosome G. tabacina (NAR). However, the F1 hybrid of AABB × AAB1B1 showed normal meiosis with an average chromosome association (range) of 1.7 I (0–4) + 39.2 II (38–40). Based on this information, we cannot correctly deduce the diploid progenitor species of the 80-chromosome G. tabacina (NAR). The lack of exact genome homology may be attributed to the geographical isolation, natural mutation, and growing environmental conditions since the inception of 80-chromosome G. tabacina. Thus, it is logical to suggest that the 80-chromosome G. tabacina (NAR) is a complex, probably synthesized from A genome (G. canescens, G. clandestina, G. argyrea, G. tomentella D4 isozyme group) and B genome (G. latifolia, G. microphylla, G. tabacina) species, and the 80-chromosome G. tabacina (WAR) complex was evolved through segmental allopolyploidy from the B genome species.Key words: Glycine spp., allopolyploidy, colchicine, genome, intra- and inter-specific hybridization, polyploid complex.

scholarly journals Prevalence of multidrug-resistant Acinetobacter baumannii in a critical care setting: A tertiary teaching hospital experience

2021 ◽  
Vol 9 ◽  
pp. 205031212110011
Author(s):  
Thabit Alotaibi ◽  
Abdulrhman Abuhaimed ◽  
Mohammed Alshahrani ◽  
Ahmed Albdelhady ◽  
Yousef Almubarak ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Mortality Rate ◽  
Acinetobacter Baumannii ◽  
Care Setting ◽  
Multidrug Resistant ◽  
University Hospital ◽  
Published Data ◽  
Tertiary Teaching ◽  
The Mean

Background: The management of Acinetobacter baumannii infection is considered a challenge especially in an intensive care setting. The resistance rate makes it difficult to manage and is believed to lead to higher mortality. We aim to investigate the prevalence of Acinetobacter baumannii and explore how different antibiotic regimens could impact patient outcomes as there are no available published data to reflect our population in our region. Methods: We conducted a retrospective review of all infected adult patients admitted to the intensive care unit at King Fahad University Hospital with a confirmed laboratory diagnosis of Acinetobacter baumannii from 1 January 2013 until 31 December 2017. Positive cultures were obtained from the microbiology department and those meeting the inclusive criteria were selected. Variables were analyzed using descriptive analysis and cross-tabulation. Results were further reviewed and audited by blinded co-authors. Results: A comprehensive review of data identified 198 patients with Acinetobacter baumannii. The prevalence of Acinetobacter baumannii is 3.37%, and the overall mortality rate is 40.81%. Our sample consisted mainly of male patients, that is, 68.7%, with a mean age of 49 years, and the mean age of female patients was 56 years. The mean age of survivors was less than that of non-survivors, that is, 44.95 years of age. We observed that prior antibiotic use was higher in non-survivors compared to survivors. From the review of treatment provided for patients infected with Acinetobacter baumannii, 65 were treated with colistin alone, 18 were treated with carbapenems, and 22 were treated with a combination of both carbapenems and colistin. The mean length of stay of Acinetobacter baumannii–infected patients was 20.25 days. We found that the survival rates among patients who received carbapenems were higher compared to those who received colistin. Conclusion: We believe that multidrug-resistant Acinetobacter baumannii is prevalent and associated with a higher mortality rate and represents a challenging case for every intensive care unit physician. Further prospective studies are needed.

scholarly journals Optical Properties of Dissolved Organic Matter in Finnish and Estonian Lakes

2003 ◽  
Vol 34 (4) ◽  
pp. 361-386 ◽  
Author(s):  
L. Sipelgas ◽  
H. Arst ◽  
K. Kallio ◽  
A. Erm ◽  
P. Oja ◽  
...  
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Natural Waters ◽  
Mean Value ◽  
Published Data ◽  
Optical Parameters ◽  
Exponential Approximation ◽  
Absorption Coefficients ◽  
Specific Absorption ◽  
The Mean

The main objective of the present study is to test various methods for describing the absorption spectra of coloured dissolved organic matter (CDOM) and to determine the numerical values of some optical parameters of CDOM in lakes with diverse water quality. First, the parameters of an exponential model in different spectral intervals were determined. In addition, the suitability of some other models for the approximation of CDOM spectra was estimated. Specific absorption coefficients of CDOM were calculated from the absorption coefficients and dissolved organic carbon (DOC) concentrations. The experimental initial data were differences between spectral attenuation coefficients of filtered and distilled water. Two datasets were used: 1) for 13 Estonian and 7 Finnish lakes (altogether 404 spectra between 350 and 700 nm) measured by the Estonian Marine Institute (EMI); 2) for 10 Finnish lakes (73 spectra) measured by the Finnish Environment Institute (FEI). The spectra of CDOM absorption coefficients (aCDOM) were calculated from experimental data taking into account the correction due to scattering properties of colloids in the filtered water. The total content of CDOM in natural waters of Estonian and Finnish lakes was expressed by means of aCDOM at the wavelength of 380 nm. It varied significantly, from 0.71 to 19.5 m−1, the mean value (of all the investigated lakes) being around 6.6 m−1. Slopes of the exponential approximation varied widely, from 0.006 to 0.03 nm−1. Averaged over all lakes values of slope for the interval 380-500 nm obtained from the EMI dataset are close to those obtained from the FEI dataset: from 0.014 nm−1 (without correction) to 0.016-0.017 nm-1 (with different types of correction). These results are in good correspondence with most published data. Attempts to describe the spectra in the region of 350-700 nm by means of hyperexponential functions (∽ exp(-αλη)) show that: (1) η < 1 (in the case of traditional exponential approximation η = 1); (2) a promising idea is to seek the best fit only for wavelengths λ > λ1, where λ1 will be chosen taking into account the real shape of aCDOM spectra. The mean value of the specific absorption coefficient (a*CDOM) at the wavelength 380 nm obtained in this study (0.44 L mg−1 m−1) is close to the values published in the literature, if we assume that a*CDOM (380) is calculated using the data of dissolved organic matter (DOM). The optically non-active fraction of DOM in our study was high and therefore a*CDOM (380) was considerably higher (1.01 L mg−1 m−1) than a*CDOM (380). The results of the present work could be used in the modeling of underwater light field as well as in the interpretation of radiation measurements and optical remote sensing results.

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