Cytoplasmic Effects Research Articles

Features of alloplasmic wheat-barley substitution and addition lines (Hordeum marinum subsp. gussoneanum)-Triticum aestivum

Two alloplasmic wheat-barley substitution lines were studied: a line replaced at three pairs of chromosomes 1Hmr((IB), 5Hmar(5D), and 7Hmar(7D), and the disomic-substituted line 7Hma(7D). The lines were constructed on the basis of individual plants from BCIF8- and BC2F6 progeny of barley-wheat hybrids (H. marinum subsp. gussoneanum Hudson (=H. geniculatum All.) (2n = 28) x T. aestivum L.) (2n = 42) (Pyrotrix 28), respectively. Moreover, the alloplasmic wheat-barley ditelosomic addition line 7HLma' isolated among plants from the BC1F6 progeny of a barley-wheat amphiploid was studied, which in this work corresponds to BC2F10 and BC2F11 progeny. It was ascertained that when grown in the field, these alloplasmic lines manifest stable self-fertility. Plants of the given lines are characterized by low height, shortened ears, the fewer number of stems and ears, and of spikelets in the ear, by decreased grain productivity and weight of 1000 grains, in comparison with the common wheat cultivar Pyrotrix 28. The inhibition of trait expression in alloplasmic wheat-barley substitution and addition lines may be connected not only with the influence of wild barley chromosomes functioning in the genotypic environment of common wheat, but also with the effect of the barley cytoplasm. The alloplasmic line with substitution of chromosomes 1Hmar(1B), 5Hmar(5D), and 7Hmar(7D) or the alloplasmic line 7HLmar with ditelosomic addition have, in comparison with the common wheat cultivar Pyrotrix 28, an increased grain protein content, which is explained by the effect of wild barley H. marinum subsp. gussoneanum chromosomes.

Alloplasmic effects of Brassica napus and B. juncea on seed characteristics of B. carinata

Effects of Brassica napus (N) and B. juncea (J) cytoplasm on seed characteristics of B. carinata (C) were examined. Alloplasmic lines of B. carinata were produced from N × C and J × C hybrids by recurrent backcrossing to the BC8 generation. Fourteen sets of reciprocal crosses were used. Compared with their euplasmic sibs, alloplasmic B. carinata line seeds with B. napus cytoplasm showed reduced dormancy, higher seed weight, lower germination rate at high temperatures, higher germination rate at low temperatures, and had lower erucic acid and higher linoleic acid contents. Alloplasmic B. carinata line seeds with B. juncea cytoplasm had higher seed weight but lower germination rate than their corresponding euplasmic sibs. These results showed a cytoplasmic effect on seed development, and an influence on seed weight, dormancy, and fatty acid composition. B. carinata was more deleteriously affected by cytoplasm from B. napus than by cytoplasm of B. juncea.

Genetic analysis of abamectin resistance in Tetranychus cinnabarinus

The carmine spider mite is the most serious crop mite pests in China. Abamectin has been used to control insects and mites worldwide but carmine spider mites, Tetranychus cinnabarinus, had developed resistance to it. Genetic research on insecticide resistance has been fundamental for understanding the resistance development, studying resistance mechanisms, and designing appropriate resistance management strategies to control insect pests. A resistant colony of T. cinnabarinus, RRG42 , was established to examine the inheritance of abamectin resistance in T. cinnabarinus. The females of T. cinnabarinus were selected for bioassay using a slide dip method. After 42 generations of selection, the RRG42 strain was 8.7-fold resistant to abamectin compared with the susceptible strain (SS). The logarithm (log) concentration–probit response curve for F 1s from reciprocal crosses, of F 1RS and F 1SR, were inclined to that for SS and the degree of dominance ( D) values for F 1s were −0.81 and −0.17. There was a significant difference in values of LC 50 and slope of log concentration–probit lines between F 1RS and F 1SR. The observed mortalities of BC1 (F 1RS♀ × RRG42♂) and BC1′ (F 1SR♀ × SS♂) were significantly different from the expected mortalities based on a monogenic resistance in the chi-square tests. The inheritance of abamectin resistance in T. cinnabarinus is incompletely recessive and may be controlled by more than one gene. The maternal or cytoplasmic effect may exist in the inheritance of resistance to abamectin in T. cinnabarinus.

Current status and strategies for improvement of rice grain chalkiness

This paper reviews the current status of correlation between rice chalkiness and other rice quality characters, formative mechanism, and classical and molecular genetics for rice chalkiness. The formation of rice chalkiness proves to be a complicated physiological process and tightly relate to "source-sink" of rice, dynamics of grain filing, biosynthesis and accumulation of starch in endosperm. Rice chalkiness is a complicated quantitative trait, which is controlled by maternal effects, endosperm effects, and cytoplasmic effects. There are some stable quantitative trait loci (QTL) for rice chalkiness on many rice chromosomes. Of them, three genes controlling rice chalkiness, which have an impact on starch synthesis, starch metabolism, and fruit development, have been cloned. But the manipulative network and formative mechanisms of rice chalkiness remain unclear. At present in breeding practice, decrease of rice chalkiness has become one of the main aims in rice quality breeding, especially for indica rice. The direction of genetic research and improvement strategy of rice chalkiness in future were discussed in this review.

Análise da herança da resistência a Puccinia psidii em progênies de híbridos interespecíficos de eucalipto avaliadas sob condições naturais de infecção

A ferrugem, causada pelo fungo Puccinia psidii, e atualmente a mais importante doenca do eucalipto. Esta doenca esta amplamente disseminada pelo Brasil e causa serios danos em viveiros e plantacoes. A identificacao de germoplasma resistente aliado ao conhecimento da base genetica da resistencia sao os requerimentos primordiais para o sucesso de programas de melhoramento visando a producao de cultivares resistentes. Estudos anteriores sobre a heranca da resistencia em condicoes controladas sugerem tanto uma heranca monogenica como a participacao de pelo menos 2 genes conferindo resistencia a doenca. O objetivo deste estudo foi avaliar a resistencia a P. psidii, em condicoes de campo em quatorze progenies obtidas a partir de cruzamentos e auto-cruzamentos controlados entre quatro clones hibridos de Eucalyptus grandis Hill ex Maiden x Eucalyptus urophylla ST Blake,que contrastam para a resistencia ao fungo. Os resultados indicam que a resistencia pode ser explicada por um loco com efeito principal e pelo menos tres alelos diferentes, com interacoes entre os alelos, resultando no fenotipo de resistencia ou suscetibilidade. Entretanto, locos com menor efeito devem influenciar a resistencia, uma vez que foram observadas variacoes nas classes de severidade da escala utilizada. Nenhuma diferenca na segregacao para a resistencia foi observada entre cruzamentos reciprocos, sugerindo que nao existe influencia citoplasmatica no controle deste carater.

Characterization and Genetic Analysis of Grain Filling Rate of “Ludao” and Restorer Line C-Bao in Japonica Rice

The objective of this study was to improve the grain plumpness of Japonica hybrid rice ( Oryza sativa L.) with large panicles through crossing with a kind of primitive Japonica rice “Ludao”. Grain-filling rates of the P 1, P 2, F 1, F 2, B 1, and B 2 generations that were derived from the reciprocal crosses between a Japonica restorer “C-Bao” and Ludao were investigated at 1-7, 8-14, 15-21, 22-28, 29-35, and 36-42 d after flowering. The average grain-filling rate over whole filling duration was analyzed using the mixed major gene plus polygene inheritance models. According to the reciprocal analysis, no cytoplasmic effect was found for the average grain-filling rate. The largest filling rate appeared in the stage of 8-14 d after flowering in the P 1, P 2, and F 1 generations. The whole filling duration of Ludao was 28 d, which was 14 d shorter than that of C-Bao. The average filling rate of Ludao was larger than that of C-Bao by 50%. Based on analysis of the mean components, the inheritance of average grain-filling rate was in agreement with additive-dominance-epistasis model. Two major genes and some polygenes controlled the average filling rate with additive-dominance-epistatic effects, and the major genes played a pivotal role.

Heterosis and Combining Ability for Major Yield Traits of a New Wheat Germplasm Shannong 0095 Derived from Thinopyrum intermedium

The wheatgrass, Thinopyrum intermedium (Host) Barkworth & DR Dewey, shows many beneficial characteristics, such as big spikes and high resistance to many diseases. To transfer the beneficial genes of this species, many wheat- Thinopyrum intermedium alien chromosome lines were developed. Of them, Shannong 0095 (SN0095), a disomic substitution, has long spikes and flag-leaves, and thus may be an important genetic resource for wheat yield improvement. In order to realize its heterosis and combining ability on major yield traits, a 7 × 7 complete diallel design was made according to Griffing's Method-I. The results showed that heterosis for spike length (SPL), flag-leaf area (FLA), number of spikes per plant (NSP), number of spikelets per spike (NSL), kernels per spike (KPS), 1 000-kernel weight (TKW) and grain yield per plant (GYP) existed in all the crosses by SN0095, but heterobeltiosis occurred only for KPS, TKW, and GYP. The relative mid-parent heterosis (RMH) and relative high-parent heterosis (RHH) for GYP, which valued as high as 35.32 and 29.92% respectively, were the highest among all the traits mearsured. Though additive and non-additive gene effects and cytoplasmic effects (or cytoplasmic-nuclear interaction effects) were found in governing all the traits measured above, additive gene action played a predominant role. The results also showed that SN0095 was the best-general combiner for SPL and FLA, and high-general combiner for NSP amongst all the parents. Estimates of specific combining ability (SCA) showed that SN0095 could also make high-SCA combinations for GYP, such as SN0095 × Jimai 19 (JM19). SN0095 could be a unique and important parent in hybrid wheat breeding programs.

Inheritance of very high glucosinolate content in Ethiopian mustard seeds

AbstractSeed meal amendments rich in glucosinolates are of interest for soil pest and disease control. The Ethiopian mustard (Brassica carinata A. Braun) line N2‐6215, with very high levels of seed glucosinolates (160 μmol/g), was developed from the line C‐101 (116 μmol/g) following mutagenesis. The objective of this research was to study the inheritance of very high seed glucosinolate content. Plants of N2‐6215 were reciprocally crossed with plants of the line C‐101. The F1, F2, and BC1F1 plant generations were evaluated in two environments and seeds from individual plants were analysed for total glucosinolate content. The very high glucosinolate content in N2‐6215 seeds was largely subject to maternal control. No cytoplasmic effects were detected. The trait was found to be oligogenic and determined by at least two or three genes. The estimates of broad‐sense heritability were 0.45 and 0.58 in both environments, whereas the estimates of narrow‐sense heritability were 0.35 and 0.50. The moderate heritability and oligogenic control of the trait suggest the feasibility of breeding for increased seed glucosinolate content in Ethiopian mustard.

Inheritance of Susceptibility to Ethametsulfuron Herbicide Muster in Summer Turnip Rape (Brassica rapa L.)

The Brassica oilseed crops, Brassica rapa L., B. napus L., and B. juncea (L.) Czern. & Coss., carry the inherent property of tolerance to the acetolactate synthase–inhibiting herbicide ethametsulfuron. However, a self‐compatible line of B. rapa subsp. oleifera (DC.) Metzg. susceptible to this herbicide was isolated through single‐plant selection in a Canadian cultivar. The objective of the present study was to elucidate the genetic control of tolerance to this herbicide in B. rapa by using this susceptible line as a parent in crosses with tolerant lines. The susceptible line was crossed with two tolerant, self‐incompatible lines of oleiferous B. rapa The F2, B1 (F1 backcrossed to tolerant parent), B2 (F1 backcrossed to susceptible parent), F3, and B1S1 generation populations were generated from the crosses and were evaluated for tolerance to ethametsulfuron. A single‐gene locus was found to be involved in the control of this trait, with the tolerant phenotype being completely dominant over the susceptible. No difference in tolerance was detected in the populations derived from reciprocal crosses, suggesting the absence of cytoplasmic effects in the control of this trait. As the parents differed for self‐incompatibility, segregation for this trait was found in the F2 and backcross populations, as expected. However, self‐incompatibility allele(s) did not exert any influence on segregation of the locus controlling tolerance to ethametsulfuron.

Inheritance of Low Linolenic Acid Content in Zero‐Erucic Acid Ethiopian Mustard

Zero‐erucic acid Ethiopian mustard (Brassica carinata A. Braun) seed oil has very high linolenic acid content (210 g kg−1), which confers low oxidative stability to the oil. The line AB4 with low linolenic acid content (<30 g kg−1) has been developed. The objective of this research was to study the inheritance of low linolenic acid content in AB4. Plants of AB4 were reciprocally crossed with plants of the line 25X‐1, with wild‐type linolenic acid content. A genetic study was conducted through the analysis of the fatty acid profile of F1, F2, and F3 seed generations. Low linolenic acid content in AB4 seeds was partially recessive and not subject to maternal nor to cytoplasmic effects. F2 seeds segregated following a 1:63 (<17:>23 g kg−1) ratio, which suggested segregation of alleles at three independent loci. The three‐gene model was confirmed in the analysis of linolenic acid content in F2:3 families. Nine out of 341 F2:3 families had stable low linolenic acid content, which fitted the 1:63 ratio observed in the F2 Additionally, 1:2:1 (<8:12–33:>35 g kg−1), 1:4:11 (<8:25 – 40:>43 g kg−1), and 1:6:57 (<7:27 – 43:>47 g kg−1) segregation ratios were identified in F2:3 families, which confirmed a genetic model of three independent loci with additive effects for low linolenic acid content in the Ethiopian mustard line AB4.

Index selection on seed traits under direct, cytoplasmic and maternal effects in multiple environments

Crop seeds are important sources of protein, oil, and carbohydrates for food, animal feeds, and industrial products. Recently, much attention has been paid to quality and functional properties of crop seeds. However, seed traits possess some distinct genetic characteristics in comparison with plant traits, which increase the difficulty of genetically improving these traits. In this study, diallel analysis for seed models with genotype by environment interaction (GE) effect was applied to estimate the variance-covariance components of seed traits. Mixed linear model approaches were used to estimate the genetic covariances between pair-wise seed and plant traits. The breeding values (BV) were divided into two categories for the seed models. The first category of BV was defined as the combination of direct additive, cytoplasmic, and maternal additive effects, which should be utilized for selecting stable cultivars over multi-environments. The three genetic effects, together with their GE interaction, were included in the second category of BV for selecting special lines to be grown in specific ecosystems. Accordingly, two types of selection indices for seed traits, i.e., general selection index and interaction selection index, were developed and constructed on the first and the second category BV, respectively. These proposed selection indices can be applied to solve the difficult task of simultaneously improving multiple seed traits in various environments. Data of crop seeds with regard to four seed traits and four yield traits based on the modified diallel crosses in Upland cotton (Gossypium hirsutum L.) were used as an example for demonstrating the proposed methodology.

Variability in expression of male fertility in triticale (Xtriticosecale wittmack) with Triticum timopheevi cytoplasm

Variability in expression of male fertility in triticale (Xtriticosecalewittmack) withTriticum timopheevicytoplasmWe present a reliable, visual method for evaluation of the level of male fertility during flowering, that is indispensable for breeding of hybrid cultivars of winter triticale based on the cms-T.timopheevisystem. Detailed observations of anther development were performed on 20 F2and BC1plants derived from crosses between male-sterile and fertility restoring lines. Variation of anther development within florets, spikelets, spikes, and among spikes of the same plant was examined. Hierarchic analysis showed significant role of these factors in determination of anther development, irrespective of the level of plant fertility. The sterilizing effect of cytoplasm was always better visible in the tip and base spikelets of the spike, in the third floret, and the anther adjacent to the floret axis. Our data indicate that during selection toward male-sterile plants at anthesis, at least 5 spikes should be evaluated. Special attention should be paid to the development of the anthers at the 2ndand 7thspikelet of the spike along with the variability in anther development within spikelet and floret. The anthers in the tip and base spikelets of the spike must be precisely evaluated during selection toward restorer lines.

TEMPERATURE-BASED EXTRINSIC REPRODUCTIVE ISOLATION IN TWO SPECIES OFDROSOPHILA

Drosophila santomea and D. yakuba are sister species that live on the African volcanic island of São Tomé, where they are ecologically isolated: D. yakuba inhabits low-altitude open and semiopen habitats while D. santomea lives in higher-elevation rain and mist forest. To determine whether this spatial isolation reflected differential preference for and tolerance of temperature, we estimated fitness components of both species at different temperatures as well as their behavioral preference for certain temperatures. At higher temperatures, especially 28 degrees C, D. santomea was markedly inferior to D. yakuba in larval survival, egg hatchability, and longevity. Moreover, D. santomea females, unlike those of D. yakuba, become almost completely sterile after exposure to a temperature of 28 degrees C, and conspecific males become semisterile. Drosophila santomea adults prefer temperatures 2-3 degrees C lower than do adults of D. yakuba. Drosophila santomea, then, is poorly adapted to high temperature, partially explaining its restriction to cool, high habitats, which leads to extrinsic premating isolation and immigrant inviability. Rudimentary genetic analysis of the interspecific difference in egg hatchability and larval survival showed that these differences are due largely to cytoplasmic effects and to autosomal genes, with sex chromosomes playing little or no role.

Understanding the dynamics of biological colloids to elucidate cataract formation and develop a methodology for its early diagnosis

The eye lens is the most notable example of mammalian tissues exhibiting complex colloidal behavior. In this paper, we briefly describe how dynamics in colloidal suspensions can address selected aspects of cataracts, which is ultimately related to protein self-assembly under pathological conditions. Results from dynamic light-scattering of eye lens homogenates over a wide protein concentration were analyzed and the various relaxation modes were identified in terms of collective and self-diffusion processes. Using this information as an input, the complex relaxation pattern of the intact lens nucleus was rationalized. The model of cold cataract–a phase separation effect of the lens cytoplasm with cooling–was used to simulate a lens cataract under in vitro conditions to determine the correlation function parameters, which could be used as reliable indicators of cataract onset. The applicability of dynamic light scattering as a non-invasive, early diagnostic tool for ocular diseases is also demonstrated in light of these findings.

Therapy Related Leukemia in HIV Patients after Treatment for Non-Hodgkin Lymphoma

Therapy related secondary malignancies after NHL are well characterized in the HIV negative population. The increased risk of secondary leukemia is most commonly associated with alkylating agents, topoisomerase II inhibitors and radiation therapy. We describe 2 patients with HIV-associated Burkitt's lymphoma who subsequently developed acute leukemia.Case Report 1: An HIV positive 60 yr old male was diagnosed with Burkitt's lymphoma five years after beginning antiretroviral therapy. Lymph node flow cytometry demonstrated: CD10+, CD19+, CD20+, KAPPA+. He achieved a complete remission after completing the Vanderbilt regimen (cyclophosphamide, methotrexate, bleomycin, vincristine, and doxorubicin) (McMaster M, et al. J Clin Oncol . 1991: 9:941–946). Eight years later, he presented with acute myelomonocytic leukemia (M4) after a myelodysplastic prodrome. Flow cytometry demonstrated CD11c+, CD13+, CD33+, CD34+, CD 64+ and cytogenetics showed 5q(−) and 20q(−). He received induction chemotherapy with arsenic trioxide and low dose cytarabine. He did not achieve a remission, and died 2 months later.Case Report 2: A 45 yr old male presented with severe abdominal pain, and fever. During laparotomy, he was found to have a cecal mass consistent with Burkitt's lymphoma. A bone marrow biopsy also showed Burkitt's lymphoma: CD10+, CD19+, CD20+, CD22+, CD 38+, CD45+, CD71+. He was subsequently diagnosed with HIV with a CD4 count of 60/uL. He was treated with CODOX-M (cyclophosphamide, doxorubicin, vincristine, methotrexate, IT cytarabine, IT methotrexate) and IVAC (Ifosfamide, etoposide, cytarabine, IT methotrexate) (Magrath I, et al. J Clin Oncol 1996; 14:925–934) achieving a CR. He remained on antiretroviral therapy throughout his course. Two years later, he presented with thrombocytopenia. A bone marrow aspirate was consistent with precursor B-cell ALL CD19+, CD34+, CD79a+ and TdT+ distinct from the previous Burkitt's lymphoma. He was treated with the L20 (Clarkson B, et al. Haematol Blood Transfus 1990; 33:397–408) protocol achieving a durable CR. He continued his retroviral therapy during his treatment.Conclusions: HIV positive patients have an increased propensity to develop malignancy independent of prior chemotherapy or radiotherapy exposure. In the era of HAART, the survival of HIV positive patients has markedly improved. Although the role of chemotherapy and radiation therapy are well documented as causative agents of neoplasia, the risk of HAART therapy with toxicity of nuclear, cytoplasmic and cell membrane effects potentially inducing malignancies is less well defined. Many of these agents are considered oncogenic in animal models but have not been proven to cause tumors in humans. However, it is conceivable, given the cellular toxicities of antineoplastic and antiretroviral therapy, that in combination they could cause myelodysplasia or further lymphodysplasia. It is too early to know if HIV patients are at a greater risk for development of secondary malignancies as a long-term complication of chemotherapy. However, because recent studies have demonstrated that HIV+ patients on highly active antiretroviral therapy (HAART) have comparable responses to chemotherapy compared to HIV negative patients, we recommend that patients continue HAART while receiving treatment for malignancy. Close surveillance for the appearance of secondary leukemias is warranted.

Genetic Effects of Quality Protein Maize on Kernel Traits

To efficiently use tropical hard quality protein maize (QPM) germplasm in enriching temperate QPM germplasm, improving kernel traits, and developing hard QPM hybrids, the genetic effects and heterosis of 8 QPM inbreds with different en-dosperm traits and their F1 and F2 progenies were evaluated via Griffing I diallel mating design. The hundred-kernel weight (HKW), hundred-kernel volume (HKV), endosperm modification (EM), and kernel density (KD) showed positive heterosis in F1 and F2 generations. EM showed differences in F1 reciprocal crosses, indicating obvious maternal effect. Correlation analysis showed that values of HKW, HKV, EM, and KD in F2 generation had the biggest correlation coefficients with the average parental values. Maternal effect was the main factor on HKW, HKV, and KD, while direct genetic effect was mainly on EM. Gene actions for HKW, HKV, EM, and KD were dominant, dominant, additive, and additive dominant, respectively. Cytoplasmic effect was little for the above 4 kernel traits suggesting that kernel traits are mainly controlled by nuclear genes.

LIFETIME FITNESS IN TWO GENERATIONS OFIPOMOPSISHYBRIDS

Various models purporting to explain natural hybrid zones make different assumptions about the fitness of hybrids. One class of models assumes that hybrids have intrinsically low fitness due to genetic incompatibilities, whereas other models allow hybrid fitness to vary across natural environments. We used the intrinsic rate of increase to assess lifetime fitness of hybrids between two species of montane plants Ipomopsis aggregata and Ipomopsis tenuituba planted as seed into multiple field environments. Because fitness is predicted to depend upon genetic composition of the hybrids, we included F1 hybrids, F2 hybrids, and backcrosses in our field tests. The F2 hybrids had female fitness as high, or higher, than expected under an additive model of fitness. These results run counter to any model of hybrid zone dynamics that relies solely on intrinsic nuclear genetic incompatibilities. Instead, we found that selection was environmentally dependent. In this hybrid zone, cytoplasmic effects and genotype-by-environment interactions appear more important in lowering hybrid fitness than do intrinsic genomic incompatibilities between nuclear genes.

Exploration of cytoplasmic inheritance as a contributor to maternal effects in Welsh Mountain sheep

Cytoplasmic effects were investigated using a dataset comprising three breeding groups of Welsh Mountain sheep. The influences of cytoplasmic effects were investigated by comparing animal models with and without a random term representing cytoplasmic effects. The models were applied to the eight-week weight, scan weight (mean 152 days) and ultrasonically scanned muscle and fat depth. The animal model included the random effects of animals and the maternal additive genetic, maternal permanent environmental and maternal common environmental effects. In total there were 24 569, 10 509, 8389, 8369 records for the eight-week weight, scan weight, muscle depth and fat depth respectively. Four subsets were further analysed containing maternal lines with at least five, ten, fifteen and twenty animals/line. There was no evidence of cytoplasmic effects on eight-week weight and muscle depth. Cytoplasmic effects contributed 1–2% of phenotypic variance for scan-weight and fat depth, but the effect was generally non-significant (P > 0.05). As the number of animals per maternal line increased, the magnitude of cytoplasmic effects also increased for these traits. Direct heritability estimates for the eight-week weight, scan weight, muscle depth and fat depth using the full dataset were 0.18, 0.25, 0.24, and 0.21 respectively.

Toxicology and pharmacokinetics of piperaquine in mice

Pharmacokinetic and toxicological data for piperaquine (PQ) – a bisquinoline antimalarial drug – are limited, despite strong evidence of clinical efficacy. Our aim was to conduct a detailed toxicological investigation of PQ in Swiss mice. The study comprised three phases: (i) oral PQ phosphate (PQP) at doses ranging from 0 to 600 mg/(kg day) for 5 days. Pathology tests included haematological and biochemical indices, and histopathology of the liver, heart and kidneys. (ii) PQP doses of 0–300 mg/(kg day) for 12 days and pathology tests as described. (iii) Pharmacokinetic parameters determined from mice given 100 mg/(kg day) PQP for 5 days. Blood was harvested from mice over 56 days and plasma analysed by HPLC. Mice given low doses of PQ had stable, normal body and organ weights. Weight loss was observed in mice given high doses and was accompanied by increased liver and kidney weights. Principal haematological effects were modest fluctuations in total white cells and neutrophils; biochemical effects were elevated ALT and low albumin in high-dose groups. Liver histopathology revealed minor cytoplasmic and inflammatory effects. PQ treatment did not affect heart muscle but minor renal changes were observed at high doses. Pharmacokinetic parameters were consistent with previous studies: t ½, CL and V were 16 days, 1.36 L/(h kg) and 756 L/kg, respectively. PQ may cause minor hepatotoxicity and renal tubular cell damage, and adversely affect selected haematological indices, as demonstrated at cumulative doses approximately 50 times those recommended in humans. Significant effects in humans will likely be infrequent and dose-related.

Genetics of inbred Drosophila melanogaster XI. Further tests of the effects of cytoplasm and maternal genotype on primary non-disjunction and chromosome loss

Luning, K. G. 1984. Genetics of inbred Drosophila melanogaster. XI. Further tests of the effects of cytoplasm and maternal genotype on primary non-disjunction and chromosome loss.—Hereditas 100: 243–246. Lund, Sweden. ISSN 0018–0661. Received August 1, 1983 Three inbred lines of Drosophila melanogaster (code: “2”, “12”, and “K”) have been used in former tests of primary non-disjunction and chromosome loss. By repeated back-crossing, genome from the “K” line was introduced into cytoplasm of line “2”. F1 and F2 generations of reciprocal hybrids between lines “12” and “K” were tested for primary non-disjunction and chromosome loss. K/12 hybrids from the “K” line with “2” cytoplasm were tested in F1. Both the maternal genotype and the cytoplasm had a considerable influence on both amplitude and brood pattern of primary non-disjunction and chromosome loss. Comparisons between former tests with K/2 hybrids revealed both similarities and differences in response.