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1.
Trends Biotechnol ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38480024

RESUMO

Cell-to-cell heterogeneity presents challenges across various fields, from biomedicine to bioproduction, where precise cellular responses are vital. While single cell technologies have significantly enhanced our understanding of population heterogeneity, the predominant focus has been on monitoring intracellular compounds. Recognizing the added complexity introduced by the secretion system, in this review, we first provide a systematic overview of the distinct steps necessary for driving protein secretion. We discuss the various sources of noise acting from the synthesized preprotein to the secretory protein released based on a Gram-positive cellular system as a model. We next explore the applicability of single cell technologies for monitoring protein secretion throughout these functional stages. We also emphasize the importance of applying these single cell technologies for monitoring protein secretion during bioproduction.

2.
Sci Total Environ ; 926: 171363, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38432372

RESUMO

A new regulation has led to the prohibition of recreational hunting on estates located within Spanish National Parks (NPs). Before the ban, eleven NPs in Spain had already reported negative ecological consequences associated with high densities of wild ungulates. The new situation that has occurred after the ban signifies that policies with which to control populations of wild ungulates in NPs, most of which do not have a sufficient natural capacity to regulate populations, depend exclusively on the parks' authorities. The banning of recreational hunting implies a series of social, ecological, economic and logistic challenges. The control of wild ungulate populations in NPs requires: i) the legal basis for culling; ii) social acceptance as regards removing animals and the extractive procedures employed in NPs; iii) the long-term monitoring of wild ungulates and the damages that they cause, and iv) sufficient financial and human resources. A more integrated management and policy plan is, therefore, required, which should be supported by two pillars: i) the sustainability of natural resources and the conservation of functional environments, and ii) providing society with explanations regarding the need to manage wild ungulates. In order to bridge the potential gap between these key pillars, it is important to involve stakeholders in the decision-making processes concerning wild ungulate management. The forthcoming changes in Spanish NPs provide a promising opportunity to make a substantial improvement to wild ungulate management in these protected areas. This management approach could, moreover, serve as an example and be transferred to other protected spaces.


Assuntos
Animais Selvagens , Parques Recreativos , Animais , Humanos , Caça , Conservação dos Recursos Naturais/métodos , Mamíferos
3.
Animals (Basel) ; 14(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38396624

RESUMO

This study was performed to evaluate the anesthetic protocol used in the high-quality, high-volume spay and neuter (HQHVSN) of free-roaming cats in Seoul, Korea from 2017 to 2022. The evaluation was performed on a total of 1261 free-roaming cats, with an average weight of 3.48 ± 1.04 kg. The anesthetic combination tiletamine-zolazepam, ketamine, and xylazine (ZKX) was injected intramuscularly. The actual drug doses administered were tiletamine-zolazepam 5.52 ± 1.70 mg/kg, ketamine 8.94 ± 3.60 mg/kg, and xylazine 1.11 ± 0.34 mg/kg. Additional doses were required in 275 cats out of a total of 1261 (21.8%). Following anesthesia and surgery, 1257 cats (99.7%) were returned to their original locations. Four cats (0.3%) died postoperatively. The mean duration of anesthesia (from ZKX combination to yohimbine administration) was 26 ± 22 min for males and 55 ± 36 min for females, while the time from yohimbine administration to the recovery was 31 ± 22 min for males and 20 ± 17 min for females. The use of ZKX for HQHVSN of free-roaming cats is inexpensive, provides predictable results, can be administered quickly and easily in a small volume, and is associated with a low mortality rate during the first 72 h post-surgery.

4.
Heliyon ; 10(1): e23198, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38163248

RESUMO

Nanoparticle (NP) research is an area of scientific interest with high potential for application in biomedical, optical, and electronic fields. Due to their relatively large surface area compared to their mass, NPs can be more chemically reactive and change their reactive strength or other properties. NP-based drug delivery systems provide transport and an effective and controlled way to release the drugs. This work aimed to study the solubility and biological activity of nano-encapsulated copper metal complexes for the induction of toxicity and mortality in larvae of Aedes aegypti mosquitoes. After the nano-encapsulated metal complexes were prepared, the efficiency of this incorporation was determined by electron paramagnetic resonance, and toxicity bioassays were performed. The polymeric-based PLGA NPs encapsulating metal complexes exhibited high toxicity and specificity for target organisms (insect vectors, i.e., A. aegypti), with relatively less environmental impact and long-term control of their breeding.

5.
Health Care Anal ; 32(1): 1-14, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37477837

RESUMO

Population policy has taken two divergent trajectories. In the developing part of the world, controlling population growth has been a major tune of the debate more than a half-century ago. In the more developed part of the world, an inverse pattern results in the discussion over the facilitation of population growth. The ethical debates on population policy have primarily focused on the former and ignored the latter. This paper proposes a more comprehensive account that justifies states' population policy interventions. We first consider the reasons that support pro-natalist policies to enhance fertility rates and argue that these policies are ethically problematic. We then establish an ethics of population policy grounded on account of self-sustaining the body politic, which consists of four criteria: survival, replacement, accountability, and solidarity. We discuss the implications of this account regarding birth-control and pro-natalist policies, as well as non-procreative policies such as immigration, adoption, and unintended baby-saving strategies.


Assuntos
Crescimento Demográfico , Política Pública , Humanos , Ética
6.
Front Vet Sci ; 10: 1274243, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37964912

RESUMO

Life in contemporary cities is often dangerous for stray cats, with strikingly low survival rates. In several countries, trap-neuter-return (TNR) programs have been employed to control urban stray cat populations. Management of stray cats in urban environments is not just about applying scientific solutions, but also identifying approaches that align with local cultural and ethical values. India has an estimated 9.1 million stray cats. TNR presents as a potential method for stray cat management in India, while also improving their welfare. Yet, to date, there has been no academic exploration on Indian residents' attitudes towards stray cats. We conducted a survey in 13 cities in India reaching 763 residents, examining interactions with stray cats, negative and positive attitudes towards them, attitudes towards managing their population, and awareness of TNR. Results show a high rate of stray cat sightings and interactions. While most respondents believed that stray cats had a right to welfare, the majority held negative attitudes towards and had negative interactions with them. There was widespread lack of awareness about TNR, but, when described, there was a high degree of support. Gathering insights into opinions about stray cats, and the sociodemographic factors that impact these opinions, is an important first step to developing policies and initiatives to manage stray cat populations.

7.
Heliyon ; 9(8): e18637, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37554820

RESUMO

Objectives: Animal bite is considered a serious social, economic, and health risk for societies with poor animal bites and population management. The objective of this study was to propose a model for animal bites management in Golestan Province. Methods: The present study is a multi-method study conducted quantitatively and qualitatively. First, as a cross-sectional study, the animal bites in Golestan Province and the country were calculated and their trend was predicted. Secondly, in the qualitative study (content analysis), the challenges, barriers, and methods of animal bite control were extracted through conducting semi-structured interviews and focused group discussion meetings. Finally, the model of animal bite management was developed and it was confirmed by Round Delphi. The data were analyzed via content analysis using MAXQDA18. The participants in this study consisted of university professors, managers, and executive officers involved in animal bite and rabies control plans. Results: This study revealed that the animal bite in Golestan Province had an upward trend, as in the country, and dogs were the main cause of bites (90%). The obstacles and challenges of current animal bites control program in eight areas were expressed by the participants. Also, the animal bite management model, which was obtained from the data of different stages of this study, included nine fields and 41 sub-fields. The fields of the animal bite management model included: providing a cultural package, resolving barriers to animal population control plans, wide coverage of dog vaccination, passing and enacting preventive laws, attracting financial support, constructing standard equipment, providing proper medical services, enhancing inter-departmental coordination, and controlling rabies in the wild. This model was confirmed in a Delphi round. Conclusion: Our study indicated that Golestan Province with an average bite higher than twice the country's average is one of the leading provinces in this regard. Thus, revising the animal bite and animal population control plans in this province is necessary. The model designed in this study can be used as a practical guide by policy makers and officials to manage animal bite and related consequences in this province.

8.
J Appl Anim Welf Sci ; : 1-15, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37542395

RESUMO

Free-roaming dog populations ensue from irresponsible dog ownership and abandonment. The Society for the Prevention of Cruelty to Animals (SPCA) in Hong Kong SAR offers practical solutions to control dog population growth by providing a range of different birth control programs. We present the first results of a trial Trap Neuter Return (TNR) program in Hong Kong SAR; with a free-roaming dog population on Cheung Chau Island (southwest). During the 3-year study, the SPCA undertook surveys to assess population size and trapped, desexed, and, where possible, rehomed free-roaming dogs. We report that a total of 182 dogs were encountered during the period. We estimate that an average of 75% of the population was desexed, reaching the threshold for successful TNR studies. The results of our study show that TNR can assist with free-roaming dog population control and provide guidance for future programs, in Asia and Hong Kong SAR.

9.
Animals (Basel) ; 13(6)2023 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-36978633

RESUMO

The nutria (Myocastor coypus), an invasive alien species, is widely spread in Europe. Pursuant to regulation (EU) no. 1143/2014, the nutria is subject to management programs to reduce its spread. Surgical fertility control is considered an acceptable method, particularly in urban circumstances, avoiding euthanasia. To maintain the hormonal patterns and the social and behavioral dynamics, surgical infertilization preserving the gonads (i.e., salpingectomy and vasectomy) is recommended. Mini-invasive surgery is an eligible choice when dealing with wildlife, allowing reduced captivation time. For these reasons, 77 free-ranging nutrias, captured in urban nuclei in Italy, underwent infertilization under general anesthesia; laparoscopic salpingectomy and vasectomy were performed on 32 animals and traditional surgery on the remainder, leaving the gonads in place. A three-port technique was used, with two paramedian trocars (5 mm) for the instruments and a median one for the telescope. Ablation was obtained through Onemytis® plasma device, allowing a rapid surgical time with no need to place visceral sutures; the skin was surgically closed. After recovery, the animals were released, and no overt complications were noted. No modification of the behavioral patterns was noted, and the population decreased during the following months.

10.
Animals (Basel) ; 13(3)2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36766328

RESUMO

Capybaras are the largest rodents cohabiting with humans within urban and peri-urban green areas and are known by their prolificity. Surgical contraception has been recommended by official organizations as a way to control capybara populations in areas of zoonotic disease transmission, but little data are available concerning surgical anatomy. To obtain objective anatomical descriptions related to reproductive organs, eight female capybaras cadavers were dissected. The stratigraphy of the lateral (flank) and ventral, post-umbilical (on the linea alba) abdominal wall is described as well as the vascular anatomy of reproductive organs and their syntopy with the abdominal viscera. We commented on the access to the uterine tubes and uterine horns for each approach, and for better description of abdominal wall stratigraphy, abdominal ultrasonography was performed in one live female. All of the animals were provenient from "in situ" population management projects that were properly authorized. Similar abdominal wall stratigraphy was found in comparison to domestic mammals, with emphasis on a thick cutaneous muscle, a thin linea alba, and a large, loose cecum. The uterine tubes were easily accessed by bilateral laparotomy, allowing tubal removal/ligation procedures, while uterine horn exposure was more readily reached by a midline post umbilical celiotomy, favoring horn ligature and hysterotomy techniques. This study can help achieve more efficient contraceptive surgeries in capybaras, reducing the total surgical time and enhancing animal welfare.

11.
Dev World Bioeth ; 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36649588

RESUMO

The Islamic government of Iran recently passed and announced a new law titled "Rejuvenation of the Population and Protection of the Family." This legislation is a noteworthy example of biopolitics-influenced biolaw. In terms of abortion, contraception, prenatal screening, and population control, this law clearly contrasts with women's fundamental rights and freedoms and has significant health-related consequences for different sectors of the population. A historical review of the population policies of the Islamic Republic of Iran shows the occurrence of multiple abrupt and radical changes in such policies over the past four decades. This new law, promoted by religious biopolitics, is the most recent example, and places stringent limits on abortion. According to it, all decisions concerning abortion must be made in courts rather than in health clinics. Such courts are typically presided over by male religious scholars. This law also limits prenatal screening to the degree that will increase the rate of genetic defects, especially in the population's lower socioeconomic strata. By strictly limiting access to contraception, this law will increase the rate of unwanted pregnancies and sexually transmitted diseases. This paper argues that such an influence of biopolitics on biolaw contrasts with the principles of bioethics. Still, Iran's current institution of bioethics cannot address it effectively. Therefore, a new model of interaction between bioethics, biopolitics, and biolaw is needed to prevent the detrimental consequences of such pieces of legislation. Such a paradigm shift is demanded by the current "Woman, Life, Freedom" movement of the Iranian people.

12.
Vaccines (Basel) ; 11(1)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36679998

RESUMO

Contraceptive vaccines are designed to stimulate autoimmune responses to molecules involved in the reproductive process. A mouse-specific peptide from zona pellucida 3 (mZP3) has been proposed as a target epitope. Here, we employed a plant expression system for the production of glycosylated mZP3 and evaluated the immunogenicity of plant-produced mZP3-based antigens in a female BALB/c mouse model. In the mZP3-1 antigen, mZP3 fused with a T-cell epitope of tetanus toxoid, a histidine tag, and a SEKDEL sequence. A fusion antigen (GFP-mZP3-1) and a polypeptide antigen containing three repeats of mZP3 (mZP3-3) were also examined. Glycosylation of mZP3 should be achieved by targeting proteins to the endoplasmic reticulum. Agrobacterium-mediated transient expression of antigens resulted in successful production of mZP3 in Nicotiana benthamiana. Compared with mZP3-1, GFP-mZP3-1 and mZP3-3 increased the production of the mZP3 peptide by more than 20 and 25 times, respectively. The glycosylation of the proteins was indicated by their size and their binding to a carbohydrate-binding protein. Both plant-produced GFP-mZP3-1 and mZP3-3 antigens were immunogenic in mice; however, mZP3-3 generated significantly higher levels of serum antibodies against mZP3. Induced antibodies recognized native zona pellucida of wild mouse, and specific binding of antibodies to the oocytes was observed in immunohistochemical studies. Therefore, these preliminary results indicated that the plants can be an efficient system for the production of immunogenic mZP3 peptide, which may affect the fertility of wild mice.

13.
Nutr Neurosci ; 26(12): 1194-1201, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36352561

RESUMO

BACKGROUND: Recently, dietary inflammatory index (DII) has been introduced as a significant risk factor for MS. We examined the interaction between dietary inflammatory index and some formerly demonstrated key risk factors of multiple sclerosis (MS). MATERIAL AND METHODS: We conducted a population-based incident case-control study of 547 MS cases and 1057 controls. Multiplicative and additive interaction were assessed using interaction term in the logistic regression model and synergy index (SI), respectively. RESULTS: Additive interaction was detected between DII and drug abuse (SI = 2.58; 95% CI: 1.14-5.82), gender (SI = 2.00; 95% CI: 1.39-2.87) and history of depression (SI = 1.68; 95% CI: 1.04-2.72) on the risk scale. The risk of MS in drug abusers with DII ≥ 0 was 10.4-times higher than that in non-drug abusers with DII < 0 (OR = 10.4, 95% CI: 5.12-21.02, P < 0.001). We also found that women with DII ≥ 0 had a 9.2 times larger risk compared with the men with DII < 0(OR = 9.2, 95% CI: 6.3-13.5, P < 0.001). Similarly, the risk of MS was remarkably higher in those with a history of depression and DII >0 (OR = 7.6, 95% CI: 5.1-11.5, P < 0.001). There was no evidence of multiplicative interaction between DII and the other risk factors of MS on the risk scale. CONCLUSIONS: We identified additive interaction between DII and drug abuse, gender and history of depression on MS. Further studies are needed to understand the underlying mechanisms of these detected interactions.


Assuntos
Esclerose Múltipla , Transtornos Relacionados ao Uso de Substâncias , Masculino , Humanos , Feminino , Esclerose Múltipla/epidemiologia , Esclerose Múltipla/etiologia , Estudos de Casos e Controles , Fatores de Risco , Dieta/efeitos adversos , Inflamação/complicações
14.
Front Vet Sci ; 9: 1002407, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439352

RESUMO

This study aimed to compare the analgesic effects of an injectable protocol using multimodal analgesia with or without opioids in cats undergoing ovariohysterectomy (OVH). Thirty-two healthy cats were enrolled in a prospective, blinded, randomized trial after the caregiver's written consent. Cats received a combination of ketamine (4 mg/kg), midazolam (0.25 mg/kg) and dexmedetomidine (40 µg/kg), and either buprenorphine (20 µg/kg) or saline (same volume as buprenorphine) intramuscularly [opioid-sparing (OSA) and opioid-free anesthesia (OFA) groups, respectively]. Intraperitoneal bupivacaine 0.25% (2 mg/kg) and meloxicam (0.2 mg/kg subcutaneously) were administered before OVH. Atipamezole (400 µg/kg intramuscularly) was administered at the end of surgery. Pain and sedation were evaluated using the Feline Grimace Scale (FGS) and a dynamic interactive visual analog scale, respectively. Intravenous buprenorphine was administered as rescue analgesia if FGS scores ≥ 0.39/1. Statistical analysis included repeated measures linear mixed models, Fisher's exact test and Bonferroni adjustments when appropriate (p < 0.05). Twenty-seven cats were included. The prevalence of rescue analgesia was lower in OSA (n = 0/13) than in OFA (n = 5/14) (p = 0.04). The FGS scores (least square means and 95% CI) were higher in OFA at 1 [2.0 (1.3-2.7)] and 2 h [2.2 (1.5-2.9)] than baseline [0.7 (0.0-1.4)], but not in OSA. Sedation scores were not significantly different between groups. Opioid-free injectable anesthesia was appropriate for some cats using a multimodal approach. However, a single dose of intramuscular buprenorphine eliminated the need for rescue analgesia and assured adequate pain management after OVH in cats.

15.
Theor Popul Biol ; 148: 86-94, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36379299

RESUMO

This study deals with the problem of the population shrinking in habitats affected by aging and excessive migration outflows. First, a control-oriented population dynamics model was proposed that catches the effect of depopulation. The model also includes the effect of spatial interaction-driven migration flows on population size. The resulting model is a non-homogeneous ordinary differential equation. It includes such phenomena that are important from the control point of view, such as the influence of migration costs on population dynamics, the impact of aging on population size, or the effect of the habitats' carrying capacity on migration flows. Based on the model, controllability conditions are formulated and a control strategy was developed that is meant to avoid the depopulation of the habitat. The control method acts on the migration costs to achieve the control goal and requires only population size measurements. Simulation measurements are presented in the paper to show the effectiveness of the proposed modeling and control methods.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Dinâmica Populacional , Densidade Demográfica , Simulação por Computador
16.
R Soc Open Sci ; 9(6): 211619, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35706677

RESUMO

We consider age-structured models with an imposed refractory period between births. These models can be used to formulate alternative population control strategies to China's one-child policy. By allowing any number of births, but with an imposed delay between births, we show how the total population can be decreased and how a relatively older age distribution can be generated. This delay represents a more 'continuous' form of population management for which the strict one-child policy is a limiting case. Such a policy approach could be more easily accepted by society. Our analyses provide an initial framework for studying demographics and how social constraints influence population structure.

17.
Animals (Basel) ; 12(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35681870

RESUMO

The One Welfare concept is proposed to guide humans in the ethical treatment of non-human animals, each other and the environment. One Welfare was conceptualized for veterinarians but could be a foundational concept through which to promote the ethical treatment of animals that are outside of direct human care and responsibility. However, wild-living animals raise additional ethical conundrums because of their multifarious values and roles, and relationships that humans have with them. At an open facilitated forum, the 2018 Robert Dixon Memorial Animal Welfare Symposium, a panel of five experts from different fields shared their perspectives on "loving and hating animals in the wild" and responded to unscripted questions from the audience. The Symposium's objectives were to elucidate views on the ethical treatment of the native and invasive animals of Australia and to identify some of the resultant dilemmas facing conservationists, educators, veterinarians and society. Here, we document the presented views and case studies and synthesize common themes in a One Welfare framework. Additionally, we identified points of contention that can guide further discourse. With this guide in place, the identification and discussion of those disparate views was a first step toward practical resolutions on how to manage wild-living Australian fauna ethically. We concluded that there was great utility in the One Welfare approach for any discourse about wild animal welfare. It requires attention to each element of the triple bottom line and ensures that advocacy for one party does not vanquish the voices from other sectors. We argue that, by facilitating a focus on the ecology in the context of wild animal issues, One Welfare is more useful in this context than the veterinary context for which it was originally developed.

18.
J Feline Med Surg ; 24(10): e302-e309, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35762270

RESUMO

OBJECTIVES: Ear-tipping practices and the meaning of the ear tip in trap-neuter-return (TNR) programs have not been well documented. The purpose of this study was to report the frequency of common ear-tipping practices in the USA, to identify the most effective methods and to establish a foundation for ear-tipping practice standards. METHODS: An anonymous 24-question survey was advertised from 4 to 20 October 2021 to individuals who participate in TNR programs that routinely perform ear tipping. RESULTS: There were 526 survey responses from individuals who participate in TNR programs, of whom 410 completed the survey. For ear-tip meaning, nearly 100% of respondents indicated that an ear tip meant that a cat had been sterilized. Several respondents answered that it also indicated rabies vaccination or socialization status, with 92 (22%) selecting both, 79 (19%) selecting rabies only and 50 (12%) selecting unsocial only. The majority of respondents tipped the left ear (81%), used a visual estimate to determine the cut (92%) and described the ideal silhouette as straight across (92%). The median percentage of cats where ear tips bled after initial hemostasis was 5% (interquartile range [IQR] 2-10), and the median percentage of negative feedback regarding the ear tip was 1% (IQR 0-5). In terms of weighted rank order, the most common feedback was that too much ear tip was removed (5.5), followed by a cat being ear tipped in error (4.7), persistent bleeding (4.2) and not enough ear tip being removed (4.2). Responses revealed heterogeneity regarding technique for both excision and hemostasis, as well as personnel performing the procedure. There were no significant associations between techniques and bleeding or negative feedback. CONCLUSIONS AND RELEVANCE: There is variation in the methods for performing an ear tip, as well as what an ear tip signifies. Standards for this procedure would be helpful.


Assuntos
Doenças do Gato , Raiva , Animais , Gatos , Raiva/veterinária , Inquéritos e Questionários , Estados Unidos
19.
Front Microbiol ; 13: 869509, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35547126

RESUMO

Microbial populations can adapt to adverse environmental conditions either by appropriately sensing and responding to the changes in their surroundings or by stochastically switching to an alternative phenotypic state. Recent data point out that these two strategies can be exhibited by the same cellular system, depending on the amplitude/frequency of the environmental perturbations and on the architecture of the genetic circuits involved in the adaptation process. Accordingly, several mitigation strategies have been designed for the effective control of microbial populations in different contexts, ranging from biomedicine to bioprocess engineering. Technically, such control strategies have been made possible by the advances made at the level of computational and synthetic biology combined with control theory. However, these control strategies have been applied mostly to synthetic gene circuits, impairing the applicability of the approach to natural circuits. In this review, we argue that it is possible to expand these control strategies to any cellular system and gene circuits based on a metric derived from this information theory, i.e., mutual information (MI). Indeed, based on this metric, it should be possible to characterize the natural frequency of any gene circuits and use it for controlling gene circuits within a population of cells.

20.
BMC Biol ; 20(1): 103, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35549698

RESUMO

BACKGROUND: The coral-Symbiodiniaceae symbiosis is fundamental for the coral reef ecosystem. Corals provide various inorganic nutrients to their algal symbionts in exchange for the photosynthates to meet their metabolic demands. When becoming symbionts, Symbiodiniaceae cells show a reduced proliferation rate and a different life history. While it is generally believed that the animal hosts play critical roles in regulating these processes, far less is known about the molecular underpinnings that allow the corals to induce the changes in their symbionts. RESULTS: We tested symbiont cell proliferation and life stage changes in vitro in response to different nutrient-limiting conditions to determine the key nutrients and to compare the respective symbiont transcriptomic profiles to cells in hospite. We then examined the effects of nutrient repletion on symbiont proliferation in coral hosts and quantified life stage transitions in vitro using time-lapse confocal imaging. Here, we show that symbionts in hospite share gene expression and pathway activation profiles with free-living cells under nitrogen-limited conditions, strongly suggesting that symbiont proliferation in symbiosis is limited by nitrogen availability. CONCLUSIONS: We demonstrate that nitrogen limitation not only suppresses cell proliferation but also life stage transition to maintain symbionts in the immobile coccoid stage. Nutrient repletion experiments in corals further confirmed that nitrogen availability is the major factor limiting symbiont density in hospite. Our study emphasizes the importance of nitrogen in coral-algae interactions and, more importantly, sheds light on the crucial role of nitrogen in symbiont life history regulation.


Assuntos
Antozoários , Dinoflagellida , Animais , Antozoários/fisiologia , Proliferação de Células , Dinoflagellida/genética , Ecossistema , Nitrogênio , Simbiose/fisiologia
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