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1.
Zoolog Sci ; 41(1): 97-104, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38587522

RESUMEN

Grass puffer is a semilunar-synchronized spawner: spawning occurs on beaches only for several days of spring tide around new moon (lunar age 0) and full moon (lunar age 15) every 2 weeks from spring to early summer. To investigate the role of kisspeptin and gonadotropin-inhibitory hormone (GnIH) in the semilunar-synchronized spawning, lunar age-dependent expression of the genes encoding kisspeptin (kiss2), kisspeptin receptor (kissr2), GnIH (gnih), GnIH receptor (gnihr), gonadotropin-releasing hormone 1 (GnRH1) (gnrh1), and three gonadotropin (GTH) subunits (gpa, fshb, lhb) was examined in the male grass puffer, which was kept in an aquarium under natural light condition in a lunar month during the spawning period. In the brain, both kiss2 and kissr2 showed lunar variations with a peak at lunar age 10, while both gnih and gnihr showed semilunar variations with two peaks at lunar age 0 and 20. On the other hand, gnrh1 showed semilunar variation with two peaks at lunar age 0 and 15. In the pituitary, kiss2, kissr2, gnih, and gnihr showed similar variations to those shown in the brain. The fshb and lhb mRNA levels showed semilunar variations with two peaks at lunar age 0 and 15. The present study shows lunar and semilunar oscillations of kiss2/kissr2 and gnih/gnihr expressions, respectively, with their peaks around spring tide in the brain and pituitary along with the semilunar expressions of gnrh1 and the pituitary GTH subunit genes. These results suggest that the lunar age-dependent expressions of the kisspeptin, GnIH, and their receptor genes may be primarily important in the control of the precisely timed semilunar spawning of the grass puffer.


Asunto(s)
Kisspeptinas , Tetraodontiformes , Masculino , Animales , Luna , Estaciones del Año , Gonadotropinas
2.
J Therm Biol ; 121: 103837, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38552447

RESUMEN

Hypoxic aquatic environments occur more frequently as a result of climate change, thereby exerting challenges on the physiological and metabolic functions of aquatic animals. In this study, a model fish, zebrafish (Danio rerio) was used to observe the climate-induced hypoxic effect on the upper thermal limit (critical thermal maximum; CTmax), hemoglobin, and blood glucose levels, and abnormalities of erythrocytes at cellular and nuclear level. The value of CTmax decreased significantly under hypoxia (39.10 ± 0.96 °C) compared to normoxia (43.70 ± 0.91 °C). At CTmax, hemoglobin levels were much lower (9.33 ± 0.60 g/dL) and blood glucose levels were significantly higher (194.20 ± 11.33 mg/L) under hypoxia than they were under normoxia and at the beginning of the experiment. Increased frequencies of abnormalities in the erythrocytes at both cellular (fusion, twin, elongated, spindle and tear drop shaped) and nuclear (micronucleus, karyopyknosis, binuclei, nuclear degeneration and notched nuclei) levels were also found under hypoxia compared to normoxia. These results suggest that hypoxic conditions significantly alter the temperature tolerance and subsequent physiology in zebrafish. Our findings will aid in the development of effective management techniques for aquatic environments with minimum oxygen availability.


Asunto(s)
Glucemia , Eritrocitos , Hemoglobinas , Pez Cebra , Animales , Pez Cebra/fisiología , Hemoglobinas/metabolismo , Eritrocitos/metabolismo , Eritrocitos/fisiología , Glucemia/metabolismo , Glucemia/análisis , Hipoxia/fisiopatología , Termotolerancia , Oxígeno/metabolismo , Oxígeno/sangre , Temperatura
3.
Ecotoxicol Environ Saf ; 250: 114510, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36608564

RESUMEN

Globally, microplastics (MPs) contamination in aquatic organisms is emerging as an alarming phenomenon. In the present study, we investigated MPs in three commercially important fishes (Bombay duck Harpadon nehereus, ribbon fish Trichiurus lepturus and hairfin anchovy Setipinna phasa) in fresh and dried conditions collected from two sites (Chattogram and Kuakata) of the Bay of Bengal. It was evident that fresh T. lepturus ingested highest amount of MPs through the gills (6.41 mps/g) from Chattogram followed by in the gastrointestinal tract, GIT (6.20 mps/g) and in the muscle (1.20 mps/g) from Kuakata. Among the fresh fishes, H. nehereus from Kuakata accumulated highest amount of MPs (0.21 mps/g), while S. phasa from Kuakata contained the least amount of MPs (0.06 mps/g). On the other hand, among the dried fishes, T. lepturus from Kuakata contained highest amount of MPs (46.00 mps/g), while S. phasa from Kuakata retained lowest amount of MPs (2.17 mps/g). Strangely, all the dried fishes showed significantly higher amount of MPs compared to fresh fishes from both the locations. Fiber was the most dominant type of shape of MPs which accounted 66 %, followed by fragment (27.38 %), microbeads (3.59 %), film (1.48 %), foam (1.31 %) and pellet (0.25 %). Size-wise, the major portion (39.66 %) of MPs was present to be in size range less than 0.5 mm followed by 37.67 % in the size range of 0.5-1.0 mm group and rest 22.67 % within 1.0-5.0 mm. Red (41.55 %) colored MPs was the most prominent, followed by brown (22.11 %), blue (16.32 %), pink (11.69 %), purple (5.10 %), and green (2.25 %). Among polymer types, low-density polyethylene (LDPE) was the most common (38 %), followed by polystyrene (PS-22 %), polyvinyl chloride (PVC-16 %), polyamide (PA-13 %) and ethylene-vinyl acetate (EVA-9 %). The present study confirms high occurrence of MPs in the dried fishes over the fresh fishes from the Bay of Bengal, with high potential of trophic transfer to the human body.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Humanos , Animales , Plásticos , Cuerpo Humano , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Peces
4.
Fish Shellfish Immunol ; 120: 569-589, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34963656

RESUMEN

Aquaculture plays an increasingly significant role in improving the sustainability of global fish production. This sector has been intensified with the advent of new husbandry practices and the development of new technology. However, the increasing intensification and indiscriminate commercialized farming has enhanced the vulnerability of cultivated aquatic species to damage from pathogens. In efforts to confront these various diseases, frequent use of drugs, antibiotics, chemotherapeutics, and agents for sterilization have unintentionally added to the risk of transmission of pathogens and harmful chemical compounds to consumers. Some natural dietary supplements are believed to have the potential to offset this setback in aquaculture. Application of bio-friendly feed additives such as probiotics, prebiotics and synbiotics are becoming popular dietary supplements with the potential to not only improve growth performance, but in some cases can also enhance immune competence and the overall well-being of fish and crustaceans. The present review discusses and summarizes the effects of probiotics, prebiotics and synbiotics application on growth, stress mitigation, microbial composition of intestine, immune system and health condition of aquatic animals in association with existing constraints and future perspectives in aquaculture.


Asunto(s)
Alimentación Animal/análisis , Resistencia a la Enfermedad , Peces , Prebióticos , Probióticos , Simbióticos , Animales , Acuicultura , Peces/inmunología , Peces/fisiología , Reproducción
5.
J Therm Biol ; 100: 103032, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34503781

RESUMEN

Water temperature alone can affect the growth, metabolic rates and physiological responses of aquatic organisms. Our earlier study reported that higher temperature affects cellular and hemato-biochemical responses in rohu, Labeo rohita. In this backdrop, the present study assessed the effect of higher acclimation temperature on the regulatory mechanisms of growth and stress responses of juvenile L. rohita acclimatized in three temperature conditions (30 °C, 33 °C, and 36 °C) for a period of 30 days. The relative expression of genes for growth hormone (GH), insulin-like growth factors (IGF-1 and IGF-2) and heat shock proteins (hsp70 and hsp90) were measured by real-time quantitative PCR. The results revealed that the highest acclimation temperature (36 °C) significantly decreased the weight gain (WG) and specific growth rate (SGR), and increased the feed conversion ratio (FCR) compared to 30 °C (control), while increased WG, SGR and lowered FCR were observed in fish reared at the intermediate temperature (33 °C) compared to 30 °C. Similarly, the GH gene expression in the pituitary was significantly decreased and increased at 36 °C and 33 °C, respectively as compared to 30 °C. A significantly lower expression of IGF-1 and IGF-2, and higher expression of hsp70 and hsp90 were observed in the liver of fish at 36 °C. The results of the present study indicate that although slightly elevated temperature promotes the growth of juvenile L. rohita, the higher acclimation temperature may induce stress response and impair growth performance by suppressing GH/IGF system.


Asunto(s)
Peso Corporal , Cyprinidae/metabolismo , Proteínas de Peces/metabolismo , Hormona del Crecimiento/genética , Somatomedinas/metabolismo , Termotolerancia , Animales , Cyprinidae/crecimiento & desarrollo , Cyprinidae/fisiología , Proteínas de Peces/genética , Hormona del Crecimiento/metabolismo , Proteínas HSP90 de Choque Térmico/genética , Proteínas HSP90 de Choque Térmico/metabolismo , Somatomedinas/genética
6.
J Therm Biol ; 90: 102604, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32479398

RESUMEN

Global warming is a threat across the world that leads to estimates of the upper thermal limits of ectothermic species. Increased water temperature up-regulates oxygen consumption and metabolic rates, and alters the physiological processes. In this study, we identified the critical thermal maxima (CTmax) and physiological responses under normoxia and hypoxia in Nile tilapia, Oreochromis niloticus. CTmax was 41.25 °C under hypoxia and 44.50 °C under normoxia. Compared to normoxia, lower values of hemoglobin (Hb) and red blood cells (RBCs) were observed at the CTmax under hypoxia. In contrast, higher values of white blood cells (WBCs) and blood glucose (Glu) levels were observed at the CTmax under hypoxia. Consequently, higher frequencies of micronucleus, cellular and nuclear abnormalities of erythrocytes were observed at the CTmax under hypoxia. These results suggest that high temperature tolerance and subsequent physiology are significantly affected by the oxygen supply in Nile tilapia. As climate vulnerability is intensifying day by day, this data will be helpful in successful management practice for the aquatic environment having low oxygen content.


Asunto(s)
Cíclidos/fisiología , Calor , Oxígeno , Termotolerancia/fisiología , Animales , Recuento de Células Sanguíneas , Glucemia , Cíclidos/sangre , Eritrocitos Anormales , Hemoglobinas/análisis , Consumo de Oxígeno
7.
J Therm Biol ; 93: 102738, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33077149

RESUMEN

Increase in water temperature due to anthropogenic and climatic changes is expected to affect physiological functions of fish. In this study, we determined high temperature tolerance (CTmax) of a common aquacultured Indian major carp, rohu, Labeo rohita fingerlings (15.96 ± 0.72 g BW, 11.56 ± 0.42 cm TL) followed by acclimatization at three temperatures (30, 33, 36 °C). To determine the CTmax, we analyzed the major hemato-biochemical indices - hemoglobin (Hb), red blood cell (RBC), white blood cell (WBC), blood glucose levels, and erythrocytic nuclear abnormalities (ENAs) and erythrocytic cellular abnormalities (ECAs) of peripheral erythrocytes in the fish sampled at the start and end point at each acclimated temperature. Significantly decreased CTmax of the fish was found at 36 °C compared to 30 °C and 33 °C. The fish in the highest (36 °C) temperature were found with significantly lower Hb and RBC content and significantly higher WBC and blood glucose levels than that of the fishes in the lowest (30 °C) temperature both at the start and end points. The highest frequencies of ENAs and ECAs were found in the highest (36 °C) temperature group compared to the lowest (30 °C) temperature group at both the points. We also evaluated growth performance of the rohu fingerlings reared in the three temperatures for 60 days. The growth parameters - final weight gain, percent weight gain and specific growth rate were the highest at 33 °C and the lowest at 36 °C. The present study revealed that the highest temperature (36 °C) tested here may be hazardous to rohu and the temperature should be kept below 36 °C in the aquaculture setting to avoid physiological damage and growth and production loss to the fish.


Asunto(s)
Carpas/fisiología , Termotolerancia , Animales , Glucemia/metabolismo , Tamaño Corporal , Carpas/sangre , Carpas/crecimiento & desarrollo , Eritrocitos/metabolismo , Hemoglobinas/metabolismo
8.
Fish Physiol Biochem ; 46(6): 2323-2330, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33006002

RESUMEN

Experiencing the seasonal variation and rapid global warming in the tropical climate is a common phenomenon which challenged the aquatic organisms to adapt the physiology and behavior. To investigate the effect of high-temperature acclimation, we selected Indian major carp, rohu (Labeo rohita), a commercially important freshwater aquaculture species. Oxygen consumptions, micronucleus formation in erythrocytes, and gill histopathology were observed in L. rohita fingerlings acclimated at three temperatures (30, 33, and 36 °C) for 30 days. Results showed that the highest acclimated temperature (36 °C) induced higher oxygen consumption and increased frequency of micronucleus formation in erythrocytes. Severity of different histological alterations (hyperplasia, epithelial necrosis, telangiectasis, epithelial lifting, and hypertrophy of chloride cells) in the gills was found to be increased in the highest acclimated temperature (36 °C). These findings indicate the temperature induced adaptive responses and climate vulnerability in a changing environment.


Asunto(s)
Cyprinidae/fisiología , Temperatura , Aclimatación , Animales , Eritrocitos , Branquias/patología , Micronúcleos con Defecto Cromosómico , Consumo de Oxígeno
9.
Gen Comp Endocrinol ; 282: 113200, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31199926

RESUMEN

Gonadotropin-inhibitory hormone (GnIH) is a multifunctional hypophysiotropic neurohormone and has a stimulatory role in the control of reproduction in the grass puffer. To clarify the neuroendocrine mechanisms underlying the effect of changes in water temperature on reproduction in fish, we previously revealed that, in parallel to gonadal regression, both low and high temperature significantly decreased the expressions of the genes encoding kisspeptin (kiss2), kisspeptin receptor (kiss2r), gonadotropin-releasing hormone 1 (gnrh1) in the brain and gonadotropin (GTH) subunits (fshb and lhb) in the pituitary of sexually mature male grass puffer. In this study, we examined the changes in expression of gnih and GnIH receptor gene (gnihr) in the brain and pituitary along with the genes for growth hormone (gh) and prolactin (prl) in the pituitary of male grass puffer exposed to low temperature (14 °C), normal temperature (21 °C, as initial control) and high temperature (28 °C) conditions for 7 days. The levels of gnih and gnihr mRNAs were significantly decreased in both low and high temperature conditions compared to normal temperature in the brain and pituitary. Similarly, the gh mRNA levels were significantly decreased in both low and high temperature conditions. The prl mRNAs showed no significant changes at high temperature, whereas drastically decreased at low temperature possibly by dysfunctional cold stress. Taken together, the present results suggest that, in addition to the inhibitory effect of temperature changes on the Kiss2/GnRH1/GTH system, the suppression of GnIH/GH system may also be involved in the termination of reproduction by high temperature at the end of breeding season.


Asunto(s)
Cruzamiento , Gonadotropinas/genética , Hormona del Crecimiento/genética , Hormonas Hipotalámicas/genética , Prolactina/genética , Receptores de Gonadotropina/genética , Takifugu/genética , Temperatura , Animales , Peso Corporal , Encéfalo/metabolismo , Frío , Regulación de la Expresión Génica , Gonadotropinas/metabolismo , Hormona del Crecimiento/metabolismo , Calor , Hormonas Hipotalámicas/metabolismo , Masculino , Hipófisis/metabolismo , Prolactina/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Gonadotropina/metabolismo , Estaciones del Año
10.
J Therm Biol ; 86: 102450, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31789238

RESUMEN

Rise of water temperature as a consequence of global warming is anticipated to affect the physiological activities of fish, especially in tropical regions. In the present experiment, we exposed the Indian major carp, rohu Labeo rohita to three different temperature regimes (30 °C as control and 33 °C and 36 °C) for 60 days and observed the effects of these temperature on: major hemato-biochemical indices (Hemoglobin; Hb, Red blood cell; RBC, White blood cell; WBC and blood glucose levels), erythrocytic nuclear abnormalities (ENA), and erythrocytic cellular abnormalities (ECA) of peripheral erythrocytes along with the formation of differential leucocytes in the blood. Fish were sacrificed at day 7, 15, 30 and 60 after the start of exposure to the temperature regimes. Hb decreased significantly on days 7 and 15 at 36 °C. Throughout the study period, the decrease of RBC and increase of WBC were significant at 36 °C. Blood glucose level increased significantly initially at day 7 but decreased significantly at day 60 at 36 °C. Frequencies of ENA (binucleated, nuclear bud, nuclear bridge, karyopyknosis and notched nuclei) and ECA (twin, fusion, echinocytic, spindle, tear drop and elongated shaped) were significantly increased at the highest temperature (36 °C) at almost all of the sampling days. In the case of differential leucocyte count, high temperature caused a significant increase in the number of neutrophils and a significant decrease in the number of lymphocytes. Overall, these results indicate that chronic exposure to high temperature (36 °C) induces a number of stress responses in rohu and that temperature should be kept below 36 °C in the aquaculture setting to avoid damage to the fish.


Asunto(s)
Carpas/sangre , Enfermedades de los Peces/sangre , Trastornos de Estrés por Calor/sangre , Calor/efectos adversos , Animales , Glucemia , Núcleo Celular/patología , Recuento de Eritrocitos , Eritrocitos Anormales , Trastornos de Estrés por Calor/veterinaria , Hemoglobinas/análisis , Recuento de Leucocitos
11.
Gen Comp Endocrinol ; 265: 149-153, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29625122

RESUMEN

The seasonal, daily and lunar control of reproduction involves photoperiodic, circadian and lunar changes in the activity of kisspeptin, gonadotropin-inhibitory hormone (GnIH) and gonadotropin-releasing hormone (GnRH) neurons. These changes are brought through complex networks of light-, time- and non-photic signal-dependent control mechanisms, which are mostly unknown at present. The grass puffer, Takifugu alboplumbeus, a semilunar spawner, provides a unique and excellent animal model to assess this question because its spawning is synchronized with seasonal, daily and lunar cycles. In the diencephalon, the genes for kisspeptin, GnIH and their receptors showed similar expression patterns with clear seasonal and daily oscillations, suggesting that they are regulated by common mechanisms involving melatonin, circadian clock and water temperature. For implications in semilunar-synchronized spawning rhythm, melatonin receptor genes showed ultradian oscillations in expression with the period of 14.0-15.4 h in the pineal gland. This unique ultradian rhythm might be driven by circatidal clock. The possible circatidal clock and circadian clock in the pineal gland may cooperate to drive circasemilunar rhythm to regulate the expression of the kisspeptin, GnIH and their receptor genes. On the other hand, high temperature (over 28 °C) conditions, under which the expression of the kisspeptin and its receptor genes is markedly suppressed, may provide an environmental signal that terminates reproduction at the end of breeding period. Taken together, the periodic regulation of the kisspeptin, GnIH and their receptor genes by melatonin, circadian clock and water temperature may be important in the precisely-timed spawning of the grass puffer.


Asunto(s)
Regulación de la Expresión Génica , Gonadotropinas/genética , Kisspeptinas/genética , Receptores de Superficie Celular/genética , Reproducción/genética , Estaciones del Año , Takifugu/genética , Ritmo Ultradiano/genética , Animales , Kisspeptinas/metabolismo , Masculino , Luna , Receptores de Superficie Celular/metabolismo
12.
BMC Complement Altern Med ; 18(1): 62, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29448941

RESUMEN

BACKGROUND: Traditional healing practice is an important and integral part of healthcare systems in almost all countries of the world. Very few studies have addressed the holistic scenario of traditional healing practices in Bangladesh, although these serve around 80% of the ailing people. This study explored distinctive forms of traditional healing practices in rural Bangladesh. METHODS: During July to October 2007, the study team conducted 64 unstructured interviews, and 18 key informant interviews with traditional healers and patients from Bhabanipur and Jobra, two adjacent villages in Chittagong district, Bangladesh. The study also used participatory observations of traditional healing activities in the treatment centers. RESULTS: Majority of the community members, especially people of low socioeconomic status, first approached the traditional healers with their medical problems. Only after failure of such treatment did they move to qualified physicians for modern treatment. Interestingly, if this failed, they returned to the traditional healers. This study identified both religious and non-religious healing practices. The key religious healing practices reportedly included Kalami, Bhandai, and Spiritual Healing, whereas the non-religious healing practices included Sorcery, Kabiraji, and Home Medicine. Both patients and healers practiced self-medication at home with their indigenous knowledge. Kabiraji was widely practiced based on informal use of local medicinal plants in rural areas. Healers in both Kalami and Bhandari practices resorted to religious rituals, and usually used verses of holy books in healing, which required a firm belief of patients for the treatment to be effective. Sorcerers deliberately used their so-called supernatural power not only to treat a patient but also to cause harm to others upon secret request. The spiritual healing reportedly diagnosed and cured the health problems through communication with sacred spirits. Although the fee for diagnosis was small, spiritual healing required different types of treatment instruments, which made the treatment implicitly expensive. CONCLUSIONS: Traditional healing was widely practiced as the means of primary healthcare in rural areas of Bangladesh, especially among the people with low socioeconomic status. The extent of services showed no decline with the advancement of modern medical sciences; rather it has increased with the passage of time.


Asunto(s)
Medicina Tradicional/métodos , Terapias Espirituales/métodos , Adolescente , Adulto , Bangladesh , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Medicina Tradicional/psicología , Persona de Mediana Edad , Religión , Salud Rural , Terapias Espirituales/psicología , Recursos Humanos , Adulto Joven
13.
Fish Physiol Biochem ; 44(5): 1309-1318, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29785516

RESUMEN

The increase of water temperature due to global warming is a great concern of aquaculturists and fishery biologists. In the present study, we examined the effects of high temperature on hematological parameters and blood glucose levels in striped catfish, Pangasianodon hypophthalmus exposed to three temperature conditions (28, 32, and 36 °C) for 7 days. Fish were sacrificed at days 1, 3, and 7. Erythroblasts (Ebs), erythrocytic cellular abnormalities (ECA), and erythrocytic nuclear abnormalities (ENA) were assayed using peripheral erythrocytes of the sampled fishes. Hemoglobin (Hb) and red blood cell (RBC) significantly (P < 0.05) decreased at 36 °C after 3 and 7 days of exposure, whereas white blood cell (WBC) showed opposite scenario. Blood glucose levels significantly (P < 0.05) increased at 36 °C on day 3. Frequencies of Ebs, ECA, and ENA were found to be elevated at increased temperature. Differential leucocytes count showed significant increases in neutrophil and decreases in lymphocytes in the highest temperature (36 °C). Dissolved oxygen decreased and free CO2 increased significantly (P < 0.05) with increasing temperature, while the pH and total alkalinity of the water were almost unchanged throughout the study period. Therefore, the present study demonstrated that striped catfish feel better adaptation at 28 and 32 °C, while high temperature 36 °C is likely stressful to this fish species.


Asunto(s)
Bagres/fisiología , Eritrocitos/citología , Eritrocitos/fisiología , Calor , Agua/química , Animales , Glucemia , Bagres/sangre , Eritroblastos , Eritrocitos Anormales , Temperatura
14.
Gen Comp Endocrinol ; 243: 138-145, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-27916574

RESUMEN

Water temperature is an environmental factor of primary importance that influences reproductive function in fish. To understand the molecular and physiological mechanisms underlying the regulation of reproduction by temperature, we examined changes in expression of genes encoding kisspeptin (kiss2), kisspeptin receptor (kiss2r) and three gonadotropin-releasing hormones (gnrh1, gnrh2 and gnrh3) in the brain and genes encoding gonadotropin (GTH) subunits (gpa, fshb and lhb) in the pituitary of grass puffer exposed to a low temperature (14°C), normal temperature (21°C) and high temperature (28°C) for 7days. In addition, the plasma levels of cortisol were examined after exposed to three temperature conditions. The gonadosomatic index was significantly decreased in both low and high temperature conditions. The levels of kiss2 and kiss2r mRNAs were significantly decreased at both low and high temperature conditions compared to normal temperature (control) condition. gnrh1 but not gnrh2 were significantly decreased in both temperature conditions, while gnrh3 showed a decreasing tendency in low temperature. Consequently, the levels of fshb and lhb mRNAs were significantly decreased in both low and high temperature conditions. Interestingly, the plasma levels of cortisol were significantly increased in low temperature but remain unchanged in high temperature, suggesting that the fish were under stress in the low temperature conditions but not in the high temperature conditions. Taken together, the present results indicate that anomalous temperature have an inhibitory effect on reproductive function through suppressing kiss2/kiss2r/gnrh1/fshb and lhb expression and these changes may occur in a normal physiological response as well as in a malfunctional stress response.


Asunto(s)
Regulación de la Expresión Génica , Gonadotropinas Hipofisarias/metabolismo , Kisspeptinas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Estaciones del Año , Maduración Sexual/genética , Tetraodontiformes/metabolismo , Animales , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Gonadotropinas Hipofisarias/genética , Kisspeptinas/genética , Hipófisis/metabolismo , Receptores Acoplados a Proteínas G/genética , Reproducción/fisiología , Temperatura , Tetraodontiformes/genética , Tetraodontiformes/crecimiento & desarrollo
15.
Int Q Community Health Educ ; 37(3-4): 181-187, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28994647

RESUMEN

This study explored factors influencing the initiation of smokeless tobacco (SLT) consumption in a low socioeconomic urban community in Bangladesh. The study conducted four focus group discussions among 33 informants involves school teachers, community leaders, women, and betel-nut shops owners. The results were prepared by thematic analysis of the transcripts where informants mean age was 30 ( SD ± 6.8) years with varying level of education. Tradition of hospitality, curiosity, offer from an elderly person, and avoiding nausea during pregnancy and at time of quitting smoking were key factors for the initiation of SLT consumption. The results also revealed most people were aware about the danger of SLT consumption but, in practice, consumed frequently. The research suggested that doctors might advise people not to use any form of SLT while they seeking health services. Furthermore, community-based awareness program could minimize the wider use of SLT among low-income community in Bangladesh.


Asunto(s)
Pobreza/estadística & datos numéricos , Uso de Tabaco/epidemiología , Uso de Tabaco/psicología , Tabaco sin Humo , Adulto , Bangladesh , Femenino , Grupos Focales , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Investigación Cualitativa , Factores Socioeconómicos
16.
Gen Comp Endocrinol ; 227: 77-83, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26385315

RESUMEN

Gonadotropin-inhibitory hormone (GnIH) plays as a multifunctional neurohormone that controls reproduction in birds and mammals. LPXRFamide (LPXRFa) peptide, the fish ortholog of GnIH, has been shown to regulate the secretion of not only gonadotropin (GTH) but also growth hormone (GH) and prolactin (PRL), which are potentially important for gonadal function. To investigate the role of LPXRFa peptide on reproduction of the grass puffer, which spawns in semilunar cycles, we examined changes in the levels of gh and prl expression over the several months during the reproductive cycle, and the effects of goldfish LPXRFa peptide-1 (gfLPXRFa-1) on their expression were examined using primary pituitary cultures. The expression levels of both gh and prl showed significant changes during the reproductive cycle in both sexes with one peak in the spawning and pre-spawning periods for gh and prl, respectively. Particularly, gh showed substantial increase in expression in the spawning and post-spawning periods, indicative of its essentiality in the advanced stage of reproduction. gfLPXRFa-1 stimulated the expression of both gh and prl but there was a marked difference in response between them: gfLPXRFa-1 stimulated gh expression at a relatively low dose but little effect was observed on prl. Combined with the previous results of daily and circadian oscillations of lpxrfa expression, the present results suggest that LPXRFa peptide is important in the control of the cyclic reproduction by serving as a multifunctional hypophysiotropic factor that regulates the expression of gh and prl as well as GTH subunit genes.


Asunto(s)
Expresión Génica/efectos de los fármacos , Hormona del Crecimiento/genética , Neuropéptidos/farmacología , Hipófisis/efectos de los fármacos , Prolactina/genética , Animales , Femenino , Hormona del Crecimiento/metabolismo , Masculino , Hipófisis/metabolismo , Prolactina/metabolismo , Reproducción/efectos de los fármacos , Reproducción/fisiología , Tetraodontiformes/genética
17.
Asian-Australas J Anim Sci ; 29(4): 479-86, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26949948

RESUMEN

A previous genome-wide association study (GWAS) exposed histone deacetylase 2 (HDAC2) as a possible candidate gene for breast muscle weight in chickens. The present research has examined the possible role of HDAC2 in skeletal muscle development in chickens. Gene expression was measured by quantitative polymerase chain reaction in breast and thigh muscles during both embryonic (four ages) and post-hatch (five ages) development and in cultures of primary myoblasts during both proliferation and differentiation. The expression of HDAC2 increased significantly across embryonic days (ED) in breast (ED 14, 16, 18, and 21) and thigh (ED 14 and 18, and ED 14 and 21) muscles suggesting that it possibly plays a role in myoblast hyperplasia in both breast and thigh muscles. Transcript abundance of HDAC2 identified significantly higher in fast growing muscle than slow growing in chickens at d 90 of age. Expression of HDAC2 during myoblast proliferation in vitro declined between 24 h and 48 h when expression of the marker gene paired box 7 (PAX7) increased and cell numbers increased throughout 72 h of culture. During induced differentiation of myoblasts to myotubes, the abundance of HDAC2 and the marker gene myogenic differentiation 1 (MYOD1), both increased significantly. Taken together, it is suggested that HDAC2 is most likely involved in a suppressive fashion in myoblast proliferation and may play a positive role in myoblast differentiation. The present results confirm the suggestion that HDAC2 is a functional gene for pre-hatch and post-hatch (fast growing muscle) development of chicken skeletal muscle.

18.
Gen Comp Endocrinol ; 210: 152-60, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25034121

RESUMEN

Pain-modulatory neuropeptides, PQRFamide (PQRFa) peptides, have recently been implicated in the regulation of reproduction in fish. As a first step toward investigating the role of PQRFa peptides on reproductive function in the grass puffer Takifugu niphobles, which is a semilunar spawner, we cloned genes encoding PQRFa peptide precursor (pqrfa) and its two types of receptors (pqrfa-r1 and pqrfa-r2), and examined changes in their expression levels in the brain and pituitary over several months during the reproductive cycle. The grass puffer PQRFa peptide precursor of 126 amino acid residues contains two putative PQRFa peptides, PQRFa-1 and PQRFa-2, which correspond to NPFF and NPAF in other vertebrates, respectively. The grass puffer PQRFa-R1 and PQRFa-R2 consist of 426 and 453 amino acid residues, respectively, and contain distinct characteristics of G-protein coupled receptors. These three genes were exclusively expressed in the brain and pituitary. The expression levels of pqrfa and pqrfa-r1 were significantly increased during the late stage of sexual maturation, but low in the spawning fish just after releasing sperms and eggs. Therefore, the grass puffer PQRFa peptide may have a role in the late stage of sexual maturation before spawning via PQRFa-R1. In contrast, the pqrfa-r2 expression showed maximum levels in the spawning fish and in the post-spawning period. The present results provide fundamental data suggesting that the grass puffer PQRFa peptide may have multiple roles in the control of reproduction that are dependent on the reproductive stages.


Asunto(s)
Encéfalo/metabolismo , Regulación de la Expresión Génica , Neuropéptidos/genética , Hipófisis/metabolismo , Receptores de Neuropéptido/genética , Reproducción/fisiología , Takifugu/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Datos de Secuencia Molecular , Neuropéptidos/metabolismo , Receptores de Neuropéptido/metabolismo , Homología de Secuencia de Aminoácido , Distribución Tisular
19.
BMC Womens Health ; 15: 77, 2015 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-26395981

RESUMEN

BACKGROUND: Maternal anaemia is a common problem in pregnancy, particularly in developing countries. The study was aimed at determining the factors associated with anaemia among a group of pregnant mothers who attended an antenatal clinic in Dhaka city. METHODS: This cross-sectional study included 224 pregnant women, who visited the antenatal clinic of the Marie Stops, Dhaka. Demographic data and information on maternal age, gestational age, educational and income level, and socioeconomic status were collected from all the subjects. Haemoglobin status was measured to assess their anaemia. A qualified technician drew venous blood samples from them. The reference values of haemoglobin were categorized according to the World Health Organization (WHO) criteria as follows: normal (11 g/dL or higher), mild (10-10.9 g/dL), and moderate (7-9.9 g/dL). Mild and moderate levels of haemoglobin were defined as anaemic (haemoglobin levels of <11 g/dL). The SPSS software (Windows version 16.0. SPSS Inc, Chicago, USA) was used for analyzing data. RESULTS: The mean (±SD) age of the subjects was 26.4 ± 2.81 years. Sixty-three percent of the subjects had normal level of haemoglobin, and 37% were anaemic 26% mild and 11% moderate. Maternal anaemia was significantly associated with age (p = 0.036), education (p = 0.002), income (p = 0.001), living area (p = 0.031). Results of binary logistic regression analysis showed that maternal anaemia was also significantly associated with age (p = 0.006), educational status (primary to 8th grade, p = 0.004; secondary and above, p = 0.002), living area (0.022), and income (0.021). DISCUSSION: A significant proportion of pregnant women were found anaemic. Most data showed education has animpact on awareness to use of health services and iron supplementation should be encouraged to improve the haemoglobin levels in pregnancy. CONCLUSIONS: The results indicate that anaemia is alarmingly high among pregnant women in Dhaka city. Maternal anaemia is associated with age, education level, income level, and living area. The results suggest that pregnant women and members of their families should be urgently educated to understand the importance of antenatal care.


Asunto(s)
Anemia/etiología , Complicaciones Hematológicas del Embarazo/etiología , Prevalencia , Adolescente , Adulto , Factores de Edad , Bangladesh , Estudios Transversales , Educación , Femenino , Humanos , Renta , Embarazo , Factores Socioeconómicos
20.
Chemosphere ; 356: 141827, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38583529

RESUMEN

Microplastic pollution is drastically increasing in aquatic ecosystems and it is assumed that different sizes of microplastics have diverse impacts on the physiology of aquatic organisms. Therefore, this study was intended to examine the ingestion and size specific effects of polyamide microplastic (PA-MP) on different physiological aspects such as growth, feed utilization, survivability, blood parameters and intestinal histopathology of juvenile striped catfish (Pangasianodon hypophthalmus). In a 28-day exposure, the fish were fed with different sized PA-MP with a concentration of 500 mg per kg of feed in order to simulate highly microplastic contaminated environment. Three different treatments were set for this experiment i.e. T1, 25-50 µm (smaller microplastic); T2, 300 µm-2 mm (larger microplastic); T3, (mixed) including a control (C); each had three replicates. The highest ingestion was recorded in the gastrointestinal tract (GIT) of fish exposed to smaller PA-MP treatments (T1 followed by T3). The results also showed compromised weight gain (WG; g), specific growth rate (SGR; %/day) and feed conversion ratio (FCR) with the exposure of PA-MP. Besides, survivability significantly reduced among treatments with the ingestion of smaller sized microplastic and found lowest in T1 (65.0 ± 5.0). In addition, the presence of PA-MP in feed negatively affected the concentration of hemoglobin and blood glucose. Similarly, smaller PA-MP caused most erythrocytic cellular and nuclear abnormalities; found highest in T1 that significantly different from other treatments (p < 0.05). Various histopathological deformities were observed in fish fed with PA-MP incorporated feed. The principal component analysis (PCA) showed that the toxicity and stress imparted by smaller PA-MP affected the survivability and blood parameters where larger PA-MP caused mild to severe abnormalities. Based on eigenvector values, the major abnormalities in intestine included occurrence of epithelium columnar degeneration (ECD: 0.402; PC1), hyperplasia of internal mucosa (HISM: 0.411; PC1), beheading of villi (BV: 0.323; PC1), atrophy of mucosa (AM: 0.322; PC1), tiny vacuoles in apical villi (TV: 0.438. PC2), crypt degeneration (CD: 0.375: PC2) and atrophy of goblet cell (AGC: 0.375; PC2). Therefore, it has been speculated that the size based PA-MP ingestion in the GIT interfered with the digestion and absorption as well as caused deformities that reflected negatively in survivability and hemato-biochemical parameters of juvenile striped catfish.


Asunto(s)
Bagres , Microplásticos , Contaminantes Químicos del Agua , Animales , Bagres/fisiología , Contaminantes Químicos del Agua/toxicidad , Microplásticos/toxicidad , Intestinos/efectos de los fármacos , Intestinos/patología
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