Six female Honey possums were kept on a 15L:9D light regime to simulate a long daylength over summer. After seven weeks, three females (Group 2) were changed to a shorter daylength of 10L:14D, while the other three females (Group 1) were maintained on the long daylength. Faecal oestradiol-17beta and progestagen levels were measured during the experiment to detect any changes in reproductive rhythm, such as resumption of blastocyst development. Group 2 females were found to have very large and greatly expanded blastocysts with significantly higher levels of progestagens after the change to short photoperiod (p<0.05). In contrast, the Group 1 females had very small diapausing blastocysts and progestagen levels did not change throughout the study. Overall oestradiol levels also increased significantly in Group 2 females (p<0.05) but not in Group 1 females. These results demonstrate that a change from long to short days stimulates increased progestagen output (and oestradiol-17beta to a lesser extent) that supports the growth and expansion of the blastocysts. Photoperiod, in particular its change to a shortening daylength, appears to be a stimulus for terminating diapause in the Honey possum during its first reproduction of the year. However, as subsequent breeding later in the year occurs when daylength is increasing, a similar role for photoperiod cannot be attributed and females may be entrained to other factors such as food resources.
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http://dx.doi.org/10.1016/j.ygcen.2004.07.009 | DOI Listing |
Wound Manag Prev
December 2024
Acute Surgical Wound Service, Department of Surgery, Christiana Care, Newark, DE; Department of Surgery, Christiana Care, Newark, DE.
Background: Traumatic injuries have increased risks for infection and progression to difficult-to-heal wounds. Often, they are inadequately treated with single-purpose dressings. Involving wound care specialists allows for integrating various advanced wound treatments.
View Article and Find Full Text PDFNutrients
December 2024
Department of Dermatology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
Background/objective: Ultraviolet (UV) B radiation leads to DNA damage by generating cyclobutane pyrimidine dimers (CPDs). UVB-induced CPDs can also result in immune suppression, which is a major risk factor for non-melanoma skin cancer (NMSC). UVB-induced CPDs are repaired by nucleotide repair mechanisms (NER) mediated by xeroderma pigmentosum complementation group A (XPA).
View Article and Find Full Text PDFInsects
December 2024
Mosquitos Vetores: Endossimbiontes e Interação Patógeno-Vetor, Instituto René Rachou-Fiocruz, Belo Horizonte 30190-002, Brazil.
Malaria continues to be a major public health challenge in tropical and subtropical regions. , a key laboratory model for malaria research, plays a critical role in the study of vector-parasite interactions. Although vector life traits and environmental factors such as age and resource availability can influence the transmission potential of mosquitoes for parasites, the impact of different adult diets on their survival and reproductive fitness remains underexplored.
View Article and Find Full Text PDFCardiovasc Hematol Disord Drug Targets
December 2024
Physiology Department, Faculty of Basic Medical Sciences, University of Uyo, Uyo, Akwa-Ibom State, Nigeria.
Background: The consumption of coffee as a beverage and honey as a sweetener is prevalent worldwide, with each having potential health implications. However, studies on the combined effect of coffee and honey on blood pressure, heart rate, and blood glucose level are lacking.
Objective: The objective of this study is to determine whether a three-day consumption of honey- sweetened coffee will significantly alter the systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), and fasting blood glucose (BG) levels in young, healthy female adults.
Pak J Biol Sci
November 2024
<b>Background and Objective:</b> Betta fish is one of the most popular ornamental fish because of their attractive body shape, especially for males. The fish development usually results in a similar number of males and females or an even higher number of females. This study aimed to determine the effect of various concentrations of honey and the age of larvae on the sex ratio of Betta fish.
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