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1.
World J Clin Cases ; 12(11): 1900-1908, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38660542

RESUMO

The coexistence of venous thromboembolism (VTE) within patients with cancer, known as cancer-associated thrombosis (CAT), stands as a prominent cause of mortality in this population. Over recent years, the incidence of VTE has demonstrated a steady increase across diverse tumor types, influenced by several factors such as patient management, tumor-specific risks, and treatment-related aspects. Furthermore, mutations in specific genes have been identified as potential contributors to increased CAT occurrence in particular cancer subtypes. We conducted an extensive review encompassing pivotal historical and ongoing studies on CAT. This review elucidates the risks, mechanisms, reliable markers, and risk assessment methodologies that can significantly guide effective interventions in clinical practice.

2.
Nature ; 623(7987): 562-570, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37880372

RESUMO

Vision enables both image-forming perception, driven by a contrast-based pathway, and unconscious non-image-forming circadian photoentrainment, driven by an irradiance-based pathway1,2. Although two distinct photoreceptor populations are specialized for each visual task3-6, image-forming photoreceptors can additionally contribute to photoentrainment of the circadian clock in different species7-15. However, it is unknown how the image-forming photoreceptor pathway can functionally implement the segregation of irradiance signals required for circadian photoentrainment from contrast signals required for image perception. Here we report that the Drosophila R8 photoreceptor separates image-forming and irradiance signals by co-transmitting two neurotransmitters, histamine and acetylcholine. This segregation is further established postsynaptically by histamine-receptor-expressing unicolumnar retinotopic neurons and acetylcholine-receptor-expressing multicolumnar integration neurons. The acetylcholine transmission from R8 photoreceptors is sustained by an autocrine negative feedback of the cotransmitted histamine during the light phase of light-dark cycles. At the behavioural level, elimination of histamine and acetylcholine transmission impairs R8-driven motion detection and circadian photoentrainment, respectively. Thus, a single type of photoreceptor can achieve the dichotomy of visual perception and circadian photoentrainment as early as the first visual synapses, revealing a simple yet robust mechanism to segregate and translate distinct sensory features into different animal behaviours.


Assuntos
Ritmo Circadiano , Drosophila melanogaster , Células Fotorreceptoras de Invertebrados , Percepção Visual , Animais , Acetilcolina/metabolismo , Relógios Biológicos/fisiologia , Relógios Biológicos/efeitos da radiação , Ritmo Circadiano/fisiologia , Ritmo Circadiano/efeitos da radiação , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Drosophila melanogaster/efeitos da radiação , Retroalimentação Fisiológica , Histamina/metabolismo , Neurotransmissores/metabolismo , Células Fotorreceptoras de Invertebrados/metabolismo , Células Fotorreceptoras de Invertebrados/efeitos da radiação , Receptores Colinérgicos/metabolismo , Receptores Histamínicos/metabolismo , Percepção Visual/fisiologia , Percepção Visual/efeitos da radiação
3.
Sci Adv ; 8(35): eabo5506, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36054358

RESUMO

The master circadian clock generates 24-hour rhythms to orchestrate daily behavior, even running freely under constant conditions. Traditionally, the master clock is considered self-sufficient in sustaining free-running timekeeping via its cell-autonomous molecular clocks and interneuronal communications within the circadian neural network. Here, we find a set of bona fide ultradian oscillators in the Drosophila brain that support free-running timekeeping, despite being located outside the master clock circuit and lacking clock gene expression. These extra-clock electrical oscillators (xCEOs) generate cell-autonomous ultradian bursts, pacing widespread burst firing and promoting rhythmic resting membrane potentials in clock neurons via parallel monosynaptic connections. Silencing xCEOs disrupts daily electrical rhythms in clock neurons and impairs cycling of neuropeptide pigment dispersing factor, leading to the loss of free-running locomotor rhythms. Together, we conclude that the master clock is not self-sufficient to sustain free-running behavior rhythms but requires additional endogenous inputs to the clock from the extra-clock ultradian brain oscillators.

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