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1.
Dev Biol ; 507: 64-72, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38160963

RESUMO

Regeneration is a fascinating phenomenon observed in various organisms across the animal kingdom. Different orders of class Insecta are reported to possess comprehensive regeneration abilities. Several signalling molecules, such as morphogens, growth factors, and others trigger a cascade of events that promote wound healing, blastema formation, growth, and repatterning. Furthermore, epigenetic regulation has emerged as a critical player in regulating the process of regeneration. This report highlights the major breakthrough research on wound healing and tissue regeneration. Exploring and reviewing the molecular basis of regeneration can be helpful in the area of regenerative medicine advancements. The understanding gathered from this framework can potentially contribute to hypothesis designing with implications in the field of synthetic biology and human health.


Assuntos
Epigênese Genética , Transdução de Sinais , Animais , Humanos , Insetos
2.
Inorg Chem ; 62(30): 11966-11975, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37459483

RESUMO

The simultaneous presence of Fe3+ and As3+ ions in groundwater (higher ppb or lower ppm level concentrations at circumneutral pH) as well as in acid mine drainages (AMDs)/industrial wastewater (up to few thousand ppm concentration at strongly acidic pH) are quite common. Therefore, understanding the chemical interactions prevalent between Fe3+ and As3+ ions in aqueous medium leading to nucleation of ionic clusters/solids, followed by aggregation and growth, is of great environmental significance. In the present work, we attempt to probe the nucleation process of Fe3+-As3+ clusters in solutions of various concentrations and pHs (from AMD to groundwater-like) using a combination of experimental and theoretical techniques. Interestingly, our study reveals nucleation of primary FeAs clusters in nearly all of them independent of concentration or pH. Theoretical studies employed density functional theory (DFT) to predict the primary clusters as stable Fe4As4 units. The surprising resemblance of these clusters with known Fe3+-As3+ minerals at the local level was observed experimentally, which provides an important clue about solid-phase growth from a range of Fe3+-As3+ solutions. Our experimental findings are further supported by a stepwise reaction mechanism established from detailed DFT studies.

3.
J Exp Zool A Ecol Integr Physiol ; 339(9): 825-837, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37465962

RESUMO

In view of global environmental change, ecological factors especially temperature, affect development of the poikilotherms like insects. Since ladybirds are at risk of injury under mass-rearing conditions, their ability to regenerate injured limbs is highly crucial for their survival. Therefore, the effect of limb regeneration in relation to temperature forms the basis of the present study. The immature stages of insects, being more vulnerable to the surrounding temperature, were considered to study the effect of the prior thermal experience of larvae on regeneration. We exposed the early larval stages of the ladybird beetle, Cheilomenes sexmaculata, to different temperature conditions pre- and postamputation. Exposure of immature stages to extreme temperatures did not affect the ability to regenerate and regeneration occurred at given temperature conditions. However, the regenerated legs were smaller in size across given temperatures as compared to unamputated legs. Body weights in amputated treatments showed no difference and remained unchanged across temperatures when compared to unamputated treatments. Postamputation developmental duration, equivalent to recovery time postlimb amputation, was found to be affected by larval thermal conditions. Recovery was faster in larval treatments exposed to higher temperatures. Thus, larval thermal conditions though did not affect the ability to regenerate lost limbs directly, it does modulate the time taken to regenerate.


Assuntos
Besouros , Animais , Larva , Regeneração , Temperatura , Extremidades
4.
Behav Processes ; 206: 104835, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36706823

RESUMO

Cannibalism is taxonomically widespread and has a large impact on the individuals' fitness and population dynamics. Thus, identifying how the rates of cannibalism are affected by different ecological cues is crucial for predicting species evolution and population dynamics. In current experiment, we investigated how victim relatedness affects the cannibalistic tendencies of different life stages of ladybird, Cheilomenes sexmaculata, which is highly cannibalistic. We provided larval instars and newly emerged adults of C. sexmaculata with a choice of sibling, half-sibling and non-sibling conspecific eggs as victim of cannibalism. First victim cannibalised and latency to cannibalise were observed along with total number of victims cannibalised after 24 h. First preference of victim did not differ with life stages of the cannibals though the number of victims cannibalized did increase with advancement in stage. Percent egg cannibalism also varied significantly with life stage and victim relatedness. First and second instars tend to cannibalise more percentage of sibling and non-sibling eggs while third instars cannibalised more percentage of non-sibling eggs; fourth instars and adults on the other hand cannibalised highest percentage of eggs irrespective of their relatedness. Insignificant effect of victim relatedness was observed on latency to cannibalise eggs, though it varied significantly with the cannibal's life stage. Shortest latency to cannibalise was recorded for first instars and longest for adults and second instars. In conclusion, kin recognition and avoidance of cannibalism is stage-specific, with fourth instar and newly emerged adults being less discriminatory as compared to early stages owing to increased evolutionary survival pressure.


Assuntos
Besouros , Animais , Humanos , Canibalismo , Larva , Irmãos
5.
Bull Entomol Res ; 113(2): 212-219, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36258273

RESUMO

The effects of selection on developmental variants have not yet been rigorously investigated on variable prey quantities. We investigated the food exploitation strategy of first (F1) and fifteenth (F15) generation slow and fast developers of Propylea dissecta (Mulsant) in the presence of scarce and abundant quantities of pea aphid, Acyrthosiphon pisum (Harris), and its effect on adult body mass and reproductive attributes. Both selected slow developers and selected fast developers were higher in number than their counter unselected generation on scarce and abundant diets, respectively. Immature survivals of selected slow developers were depressed after the selection process while it was enhanced for selected fast developers on both diet regimes. On both diets, the total developmental duration was longer for selected slow developers and shorter for selected fast developers. Fecundity and percent egg viability were greater in selected fast developers with plentiful prey supply and lower in control slow developers with inadequate prey supply. More adult body mass was found for pre-selected slow developers than selected slow developers on a scarce diet but selected fast developers enhanced their body weight than unselected individuals of fast developers on an abundant diet. The present experimental evolution findings point to the presence and persistence of developmental variations with variability in their developmental and reproductive traits on allocating scarce and abundant prey supplies.


Assuntos
Afídeos , Besouros , Animais , Reprodução , Fertilidade , Alimentos , Dieta
6.
Andrologia ; 54(7): e14437, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35437806

RESUMO

The aim of the present study was to identify RNA-based signatures of male infertility by sperm transcriptome analysis. In this study, deep sequencing analyses of coding (mRNA) and regulatory (miRNA) transcriptomes were performed by pooling 15 oligo/oligoasthenozoospermic infertile sperm and 9 normozoospermic fertile sperm samples. Furthermore, interesting candidates were selected for validation by real-time PCR. The comparison of miRNAs between cases and controls identified 94 differentially expressed miRNAs, of which at least 38 have known functions in spermatogenesis. In transcriptome (mRNA) data, a total of 60,505 transcripts were obtained. The comparison of coding RNAs between cases and controls revealed 11,688 differentially expressed genes. miRNA-mRNA paired analysis revealed that 94 differentially expressed miRNAs could potentially target 13,573 genes, of which 6419 transcripts were actually differentially expressed in our data. Out of these, 3303 transcripts showed inverse correlation with their corresponding regulatory miRNAs. Moreover, we found that most of the genes of miRNA-mRNA pairs were involved in male germ cell differentiation, apoptosis, meiosis, spermiogenesis and male infertility. In conclusion, we found that a number of sperm transcripts (miRNAs and mRNAs) have a very high potential of serving as infertility/sperm quality markers.


Assuntos
Infertilidade Masculina , MicroRNAs , Humanos , Infertilidade Masculina/genética , Masculino , MicroRNAs/genética , RNA Mensageiro/genética , Sêmen , Espermatozoides , Transcriptoma
7.
Clin Exp Reprod Med ; 49(1): 57-61, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35255659

RESUMO

OBJECTIVE: This study aimed to evaluate whether human chorionic gonadotropin (hCG) therapy is beneficial for improving semen parameters and clinical hypogonadism symptoms in hypogonadic oligozoospermic or severe oligozoospermic men with low or borderline testosterone levels. METHODS: A weekly dose of 250 µg (equivalent to approximately 6,500 IU) of hCG was administered subcutaneously for 3-6 months to 56 hypogonadic oligozoospermic or severe oligozoospermic men. Semen, biochemical, and genetic analyses were performed before the start of treatment followed by analyzing semen parameters every 3 months after the start of therapy. We grouped participants into responders and non-responders depending on positive changes in semen parameters. RESULTS: Out of 56 men, 47 (83.93%) responded, while 9 (16.07%) did not. Upon statistical analysis, it was found that age did not affect the overall outcomes (p=0.292); however, men with higher body mass index (BMI; 28.09±3.48 kg/m2 ) showed better outcomes than those with low BMI (25.33±3.06 kg/m2 ) (p=0.042). The duration of therapy (in months) was higher in non-responders than in responders (p=0.020). We found significant improvements in sperm concentration (p=0.006) and count (p=0.005) after 3 months of therapy. Sperm motility and progressive motility were also found to be higher in responders, but did not show statistically significant changes. CONCLUSION: We conclude that hCG therapy can be beneficial in men with hypogonadic oligozoospermia or severe oligozoospermia.

8.
Andrologia ; 54(1): e14251, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34617300

RESUMO

The purpose of this study was to investigate the efficacy of hCG therapy in hypogonadotropic hypogonadic (HH) azoospermic males along with dissecting the prognostic value of Y-deletion analysis in these patients. Fifty-eight azoospermic infertile males with diminished testosterone levels (≤400 ng/dl) and hypogonadism symptoms were subjected to human chorionic gonadotropin (hCG) therapy, and Y-deletion analysis was undertaken. Post-treatment, 43% (25/58) patients showed improvement in sperm count with 8.6% (5/58) turning severe oligozoospermic, 24.14% (14/58) patients turning oligozoospermic and 10.54% (6/58) turning normozoospermic. Among responders, the mean sperm concentration was 8.47 ± 13.16 million/ml, sperm count was 17.05 ± 26.17 million, sperm motility was 52.59% ± 25.09% and sperm progressive motility was 26.91% ± 20.51%. Seventeen out of 25 (68%) responders and 11/33 (33%) nonresponders showed an improvement in libido post-therapy. A Y-deletion was observed in 8% (2/25) responders and in 39.39% (13 out of 33) nonresponders. The Y-deletions were more often found in nonresponders in comparison with the responders (Fisher's exact probability test, p = .007, one tailed). We conclude that hCG therapy in hypogonadotropic azoospermic males is effective in improving andrological parameters and sperm production and that Y-chromosome deletion analysis has prognostic significance in predicting the success of hCG therapy.


Assuntos
Azoospermia , Hipogonadismo , Oligospermia , Azoospermia/tratamento farmacológico , Azoospermia/genética , Humanos , Hipogonadismo/tratamento farmacológico , Hipogonadismo/genética , Masculino , Oligospermia/tratamento farmacológico , Oligospermia/genética , Prognóstico , Motilidade dos Espermatozoides , Testosterona
9.
ACS Omega ; 6(23): 14903-14910, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34151072

RESUMO

Manganese nodules from ocean bed are potential resources of Cu, Ni, and Co for which land-based deposits are scarce in India. The present work describes a novel approach of using glycerol, a nontoxic biomass-derived reductant, for the reductive acid leaching of manganese nodules. Parameters such as acid concentration, time, temperature, and pulp density were optimized for leaching. The optimal leaching conditions were found to be 10% (w/v) pulp density and 10% (v/v) H2SO4 at 80 °C with 1% (v/v) glycerol yielding >95% of Ni and >98% Cu, Co, and Mn extraction within an hour. Kinetic analysis of the data based on the initial rate method showed that the leaching process was chemical reaction-controlled with an apparent activation energy of 55.47 kJ/mol. Various oxidation intermediates of glycerol formed during leaching were identified using mass spectrometry and Raman spectroscopy, and a probable oxidation pathway of glycerol during the leaching process has been elucidated based on the analysis. Glycerol was oxidized to glyceraldehyde, glyceric acid, tartronic acid, dihydroxyacetone, hydroxy pyruvic acid, glyoxalic acid, oxalic acid, and finally converted to CO2 during leaching. The fast reaction kinetics, near-complete dissolution of manganese, and other associated metals in the nodule can be attributed to the participation of all intermediate products of glycerol oxidation in redox reactions with MnO2, enhancing the overall reduction leaching efficiency.

10.
Bull Entomol Res ; 111(1): 66-72, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32539897

RESUMO

Food availability is a fundamental factor determining an animal's potential fitness. Carry-over effects of food limitation from development to adulthood are known to influence reproduction, ageing, and tolerance to stress. We have examined the effect of stage-specific variation (before adult emergence or pre-emergence, post-emergence and post-mating) in food availability in Propylea dissecta (Mulsant). Larvae were reared separately on two different pre-emergence food regimes (abundant or restricted) until pupation. Newly emerged adults were further split into two groups and placed on abundant or restricted post-emergence regimes. After mating, females were split and reared on any one of two post-mating regimes. The results revealed that: (i) time to commence mating declined with increased food availability in pre- and post-emergence stages, (ii) mating duration increased with food availability post-emergence, (iii) highest reproduction output was observed in individuals who had abundant food pre- and post-emergence. However, food availability at the time of oviposition also had a strong influence on fecundity. Solo bouts of scarcity, regardless of which stage suffered them, were effectively managed in at least two of the three stages (pre-emergence, post-emergence, post-mating) had abundant food.


Assuntos
Besouros/fisiologia , Comportamento Predatório , Animais , Besouros/crescimento & desenvolvimento , Feminino , Fertilidade , Fome , Larva/crescimento & desenvolvimento , Larva/fisiologia , Reprodução , Comportamento Sexual Animal
11.
J Assist Reprod Genet ; 37(2): 459-469, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31919744

RESUMO

PURPOSE: To identify the frequency of Y chromosome microdeletions in Indian populations and to quantitatively estimate the significance of association between these deletions and male infertility. METHODS: A total of 379 infertile males (302 azoospermic and 77 oligozoospermic infertile males) and 265 normozoospermic fertile males were evaluated for Y chromosome microdeletions (YCD) using PCR amplification and gel electrophoresis. Meta-analyses were performed on AZFa (2079 cases and 1217 controls), AZFb (2212 cases and 1267 controls), AZFc (4131 cases and 2008 controls), and AZFb+c (1573 cases and 942 controls) deletions data to quantitatively estimate the significance of association between these deletions and male infertility in Indian populations. RESULTS: The results revealed that out of 379 infertile azoospermic and oligozoospermic males, 38 (10.02%) had AZF deletions. No deletion was found in control samples. The highest percentage of deletions was observed in the AZFc region, followed by AZFa and AZFb. Qualitative analysis showed that AZF deletions were present in 0.59 to 32.62% (average 13.48%) of infertile cases in Indian populations. Meta-analysis revealed a significant association of AZFa (OR = 6.74, p value = 0.001), AZFb (OR = 4.694, p value = 0.004), AZFc (OR = 13.575, p value = 0.000), and AZFb+c (OR = 5.946, p value = 0.018) deletions with male infertility. CONCLUSION: AZF deletions were seen in 10.02% of azoospermic and oligozoospermic cases with the highest frequency of AZFc deletions. Pooled analysis for all studies showed deletion frequency from 0.59 to 32.62% (average = 13.48%). Meta-analysis showed significant association of AZFa, AZFb, and AZFb+c deletions with male infertility. Analysis of Y chromosome microdeletions should be reckoned as an essential testing for diagnostic and therapeutic purposes.


Assuntos
Azoospermia/genética , Doenças Genéticas Ligadas ao Cromossomo Y/genética , Infertilidade Masculina/genética , Oligospermia/genética , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/genética , Adulto , Azoospermia/epidemiologia , Azoospermia/patologia , Deleção Cromossômica , Cromossomos Humanos Y/genética , Doenças Genéticas Ligadas ao Cromossomo Y/epidemiologia , Doenças Genéticas Ligadas ao Cromossomo Y/fisiopatologia , Humanos , Índia/epidemiologia , Infertilidade Masculina/epidemiologia , Infertilidade Masculina/patologia , Infertilidade Masculina/fisiopatologia , Masculino , Oligospermia/epidemiologia , Oligospermia/fisiopatologia , Reação em Cadeia da Polimerase , Aberrações dos Cromossomos Sexuais , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/epidemiologia , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/patologia , Adulto Jovem
13.
J Therm Biol ; 71: 180-188, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29301688

RESUMO

All organisms are exposed to daily as well as seasonal variation in temperature in nature. However, ectotherms are strongly affected by temperature and its variations. Most laboratory studies on effect of temperature on life history traits employ constant instead of fluctuating temperature regimes, though the latter is more reflective of nature. We conducted investigations on the effect of constant, fluctuating and alternate temperature regimes on reproductive and developmental attributes of a biocontrol agent ladybird, Menochilus sexmaculatus (Fabricius) (Coleoptera: Coccinellidae). We used three constant, viz. cold, optimum and hot (15°C, 27°C and 35°C); two fluctuating with variation in mean temperature of the day (15°C/27°C, 35°C /27°C; 10/14h) and three alternating (15°C/27°C, 35°C/27°C, 15°C/35°C; 24/24h) temperatures to evaluate their effects on these life attributes. Oviposition and percent egg viability along with offspring development (immature life stages developmental time and developmental rate) and elytral colouration pattern of adults were observed. The best response in terms of oviposition and percent egg viability was recorded at the constant temperature of 27°C followed by the fluctuating regime with a mean temperature of 30.3°C. The fastest development was found at a constant temperature of 35°C, followed by a fluctuating temperature of 35°C/27°C for 10/14h. Among the different temperature cycles, the most uncustomary trend of oviposition and percent egg viability was recorded on an alternate temperature of 15°C/35°C for 24/24h. The constant (27°C) and fluctuating (35°C/27°C for 10/14h) temperatures caused an incremental effect on reproductive output and developmental rate. This study demonstrates that M. sexmaculatus is able to adjust its physiology according to surrounding environmental conditions and acclimatizes well with the fluctuating/alternate temperatures suggesting its wide range of tolerance. The findings of present work would be helpful in augmenting population dynamics of this biocontrol agent to suppress insect pest.


Assuntos
Aclimatação , Besouros/fisiologia , Estágios do Ciclo de Vida , Oviposição , Animais , Temperatura Baixa , Besouros/crescimento & desenvolvimento , Feminino , Temperatura Alta , Masculino
14.
J Therm Biol ; 69: 275-280, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29037394

RESUMO

The present study aims to understand the influence of two thermal extremes (15°C and 35°C) as thermal stressors on the selected line of developmental variants (slow and fast developers) in Propylea dissecta and to compare it with the response at the optimal temperature (27°C). The ratio of slow and fast developers within an egg batch differed with thermal extremes irrespective of F1 and F15 generations. Adult body mass got depressed after selection for control slow developers at 15°C while it got enhanced for selected fast developers at 35°C. More selected slow developers were found at low temperature and more selected fast developers at high temperature. Selection probably favours the enhancement of immature survival and emergence ratio which was found to be highest for selected fast developers at 35°C and selected slow developers at 15°C. Population level disparity on thermal confliction was observed in ladybird post selection over several generations. Therefore, we put forward that exposure thermal extremes over a long duration, causes an adaptive differentiation in thermal responses of slow and fast developers.


Assuntos
Besouros/fisiologia , Estresse Fisiológico , Aclimatação , Animais , Tamanho Corporal , Temperatura Baixa , Besouros/crescimento & desenvolvimento , Feminino , Temperatura Alta , Masculino , Reprodução
15.
Behav Processes ; 131: 1-8, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27476769

RESUMO

Sexual selection and the mechanisms involved in sperm competition have not been greatly explored in ladybird beetles. The present study was conducted to investigate the processes of sperm competition and the role of mate guarding behaviour in its regulation in ladybird beetles. We investigated these questions in polyandrous females of the ladybird, Menochilus sexmaculatus (Coleoptera: Coccinellidae) using a phenotypic marker (typical and intermediate morph) to assess paternity of offspring; to determine sperm competition. We conducted two double mating experiments: (i) complete first and second matings, and (ii) disrupted first and complete second matings each using homomorphic and heteromorphic pairing in alternation. Males which mated last were found to sire up to 72% of the offspring produced, indicating last male sperm precedence. Morph itself, independent of mating order, did not have a significant effect on proportion of offspring sired. Paternity share of the last male was negatively associated with mating duration of the first male; mating duration of the first male being indicative of mate guarding. This therefore indicates that prolonged matings by first males are essentially examples of post-copulatory mate guarding to prevent last male sperm precedence.


Assuntos
Besouros/fisiologia , Fertilização/fisiologia , Comportamento Sexual Animal/fisiologia , Animais , Feminino , Masculino , Morfogênese/fisiologia
16.
Insect Sci ; 23(1): 117-33, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25382458

RESUMO

The effects of environmental parameters on insect development have been studied extensively. But the reasons for 2 differential developmental rates within same cohort under varying environmental factors have not been explored. For the purpose, in this study the existence and stability of slow and fast development under 5 photoperiods (i.e., 8L: 16D, 10L : 14D, 12L : 12D, 14L : 10D and 16L : 8D; light and dark hours per day) and its effect on body mass and reproductive attributes in 2 aphidophagous ladybirds, Menochilus sexmaculatus (Fabricius) and Propylea dissecta (Mulsant) was examined on Aphis craccivora Koch at 27 ± 1 °C temperature. A clear bimodal (2 peaks, where the first peak represented the fast developing and the 2nd peak slow developing individuals) pattern of distribution at each photoperiod was found. The proportion of slow and fast developing individuals in a cohort differed with photoperiods. The slow developing individuals were more in numbers at 8L : 16D, in equal numbers at 14L : 10D and in less numbers at 16L: 8D, indicating that the variation in emergence was owing to exogenous cues influenced differential rates of mortality. Slow developing individuals had female biased sex ratio, higher longevity and lower body mass than fast developing individuals. Fast developing females laid higher numbers of eggs with higher egg viability than slow developing females. Study of such variations in development at different photoperiods is helpful to understand its role in the development of insects particularly ladybirds and permits the selection of fast developing bioagents for their use in biocontrol of pest species.


Assuntos
Besouros/crescimento & desenvolvimento , Fotoperíodo , Animais , Besouros/fisiologia , Feminino , Masculino , Reprodução/fisiologia , Razão de Masculinidade , Fatores de Tempo
17.
J Exp Zool A Ecol Genet Physiol ; 323(10): 745-756, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26463402

RESUMO

Development rate polymorphism describes the scenario in which individuals exhibit distinct differences in their rate of development resulting in slow and fast developers even from the same clutch of eggs. Previously we showed that in ladybird, Propylea dissecta fast developers have higher foraging and predation rates than slow developers. But correlation between foraging efficacies with reproductive output of female remains unexplored. We selected slow and fast developmental rate for 15 generations in a P. dissecta and assessed female functional response and numerical response by using varying prey biomasses (A. pisum). We evaluated predatory parameters: prey consumption, attack rate, handling time, and the reproductive measures: number of eggs laid, egg, and body biomass conversion efficiencies. Overall, both group of P. dissecta showed increased prey biomasses curvilinear for consumption rate demonstrating the physiological capacity of foraging for food are mutually exclusive behaviors (i.e., Holling's Type-II functional response). Consumption rate and proportion of prey consumed was higher, and prey handling time was shorter, in experimental fast developers. However, prey attack rate was higher in experimental slow developers. The functional response of experimental fast developers got elevated whereas got depressed for control slow-fast developers. Our results suggest that slow developers may perform better at low prey biomass than fast developers due to their high attack rate whereas high density prey may favour fast developers due to their shorter prey handling time and higher consumption rates. This study is first attempt to evaluate predatory responses of experimentally selected lines of slow and fast developers. J. Exp. Zool. 323A: 745-756, 2015. © 2015 Wiley Periodicals, Inc.

18.
Arch Insect Biochem Physiol ; 87(3): 105-25, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25060353

RESUMO

Insect hydrocarbons (HCs) primarily serve as a waterproofing cuticular layer and function extensively in chemical communication by facilitating species, sex, and colony recognition. In this study, headspace solid-phase microextraction is employed for investigating the sex-specific volatile HC profile of five ladybirds collected from Lucknow, India namely, Coccinella septempunctata (L.), Coccinella transversalis (Fabr.), Menochilus sexmaculatus (Fabr.), Propylea dissecta (Mulsant), and Anegleis cardoni (Weise) for the first time. Major compounds reported in C. septempunctata, C. transversalis, and A. cardoni are methyl-branched saturated HCs, whereas in M. sexmaculatus, and P. dissecta, they are unsaturated HCs. Other than A. cardoni, both the sexes of the other four ladybirds had similar compounds at highest peak but with statistically significant differences. However, in A. cardoni, which is a beetle with a narrow niche, the major compound in both male and female was different. The difference in volatile HC profile of the sexes of the five ladybirds indicates that gender-specific differences primarily exist due to quantitative differences in chemicals with only very few chemicals being unique to a gender. This variation in semiochemicals might have a role in behavioral or ecological aspects of the studied ladybirds.


Assuntos
Besouros/química , Hidrocarbonetos/metabolismo , Caracteres Sexuais , Animais , Epiderme/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos/química , Índia , Masculino , Feromônios/metabolismo , Especificidade da Espécie
19.
Bull Entomol Res ; 103(5): 570-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23590838

RESUMO

Male contributions, both chemical and behavioural, can influence female sperm usage and reproductive success. To determine whether such male factors are subject to depletion in Coccinella septempunctata and Coccinella transversalis, we tested the effects of male mating history on male virility, as estimated by measures of mating behaviour, female reproductive success and progeny fitness, with parental age held constant. Overt measures of male mating effort (wriggling duration, number of shaking bouts and total copula duration) all diminished from virgin to 5×mated males and were mirrored by concurrent declines in female fecundity and fertility(measured over 20 days). Paternal effects were also observed which diminished as a function of mating history, suggesting that transgenerational signals of male origin are also subject to depletion. Progeny of virgin fathers had higher rates of survival(C. transversalis) and faster development (both species) than progeny of 5×mated fathers. Seminal fluid proteins are known to have allohormonal properties and can stimulate female fecundity and fertility in a number of insects, making them strong candidates for depletion as a function of mating activity. However, it is also possible that sperm limitation and/or reduced tactile stimulation of females by multiple-mated males may have contributed to some of the observed effects.


Assuntos
Besouros/fisiologia , Comportamento Sexual Animal/fisiologia , Animais , Feminino , Fertilidade , Masculino
20.
Menopause ; 19(6): 642-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22240638

RESUMO

OBJECTIVE: Postmenopausal osteoporosis is one of the most common metabolic bone disorders. Osteoporosis is reported to cause bone loss in the alveolar processes of maxilla and mandible, which provide bony framework for tooth anchorage. However, the association between systemic osteoporosis and oral health remains controversial. Available evidence suggests that Indian women have lower peak bone mass than their Western/other Asian counterparts. The present study evaluated the relationship between mandibular bone mineral density (mBMD), systemic skeletal BMD, and bone metabolism in premenopausal and postmenopausal Indian women. METHODS: One hundred twenty-four premenopausal and 247 postmenopausal healthy women were included in the study. The BMD of the body of mandible, radius ultradistal, total hip, femur neck, and lateral spine were measured using dual-energy x-ray absorptiometry. Serum and urine biomarkers were determined using commercial kits. RESULTS: Univariate regression analysis followed by stepwise multivariate regression analysis to obtain the best fit model demonstrated the BMD of radius ultradistal, serum inorganic phosphorus, estradiol, and sex hormone-binding globulin as significant predictors of mBMD in premenopausal women. The BMD of femur neck, serum ionized calcium, bone-specific alkaline phosphatase, osteocalcin, and urine total pyridinoline were significantly associated with mBMD in postmenopausal women. The significant association between mBMD and number of teeth present was observed in the whole group of premenopausal and postmenopausal women. CONCLUSIONS: Varied predictors of mBMD were observed in premenopausal and postmenopausal women. The results suggest that the screening for these biomarkers and serum ionized calcium should be useful (1) to assess the status of mBMD particularly in women requiring surgical dental intervention that include bone manipulation and (2) for early detection and management of women with the risk of developing osteoporosis.


Assuntos
Biomarcadores/análise , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Mandíbula , Pós-Menopausa , Pré-Menopausa , Absorciometria de Fóton , Adulto , Fosfatase Alcalina/sangue , Aminoácidos/urina , Cálcio/sangue , Feminino , Colo do Fêmur , Quadril , Humanos , Índia , Vértebras Lombares , Pessoa de Meia-Idade , Osteocalcina/sangue , Rádio (Anatomia)
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