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1.
JMIR Public Health Surveill ; 10: e41792, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349717

RESUMO

BACKGROUND: Health care avoidance in the COVID-19 pandemic has been widely reported. Yet few studies have investigated the dynamics of hospital avoidance behavior during pandemic waves and inferred its impact on excess non-COVID-19 deaths. OBJECTIVE: This study aimed to measure the impact of hospital avoidance on excess non-COVID-19 deaths in public hospitals in Hong Kong. METHODS: This was a retrospective cohort study involving 11,966,786 patients examined between January 1, 2016, and December 31, 2021, in Hong Kong. All data were linked to service, treatment, and outcomes. To estimate excess mortality, the 2-stage least squares method was used with daily tallies of emergency department (ED) visits and 28-day mortality. Records for older people were categorized by long-term care (LTC) home status, and comorbidities were used to explain the demographic and clinical attributes of excess 28-day mortality. The primary outcome was actual excess death in 2020 and 2021. The 2-stage least squares method was used to estimate the daily excess 28-day mortality by daily reduced visits. RESULTS: Compared with the prepandemic (2016-2019) average, there was a reduction in total ED visits in 2020 of 25.4% (548,116/2,142,609). During the same period, the 28-day mortality of non-COVID-19 ED deaths increased by 7.82% (2689/34,370) compared with 2016-2019. The actual excess deaths in 2020 and 2021 were 3143 and 4013, respectively. The estimated total excess non-COVID-19 28-day deaths among older people in 2020 to 2021 were 1958 (95% CI 1100-2820; no time lag). Deaths on arrival (DOAs) or deaths before arrival (DBAs) increased by 33.6% (1457/4336) in 2020, while non-DOA/DBAs increased only by a moderate 4.97% (1202/24,204). In both types of deaths, the increases were higher during wave periods than in nonwave periods. Moreover, non-LTC patients saw a greater reduction in ED visits than LTC patients across all waves, by more than 10% (non-LTC: 93,896/363,879, 25.8%; LTC: 7,956/67,090, 11.9%). Most of the comorbidity subsets demonstrated an annualized reduction in visits in 2020. Renal diseases and severe liver diseases saw notable increases in deaths. CONCLUSIONS: We demonstrated a statistical method to estimate hospital avoidance behavior during a pandemic and quantified the consequent excess 28-day mortality with a focus on older people, who had high frequencies of ED visits and deaths. This study serves as an informed alert and possible investigational guideline for health care professionals for hospital avoidance behavior and its consequences.


Assuntos
COVID-19 , Humanos , Idoso , Pandemias , Estudos Retrospectivos , Visitas ao Pronto Socorro , Pessoal de Saúde
2.
Mol Metab ; 78: 101826, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37898450

RESUMO

OBJECTIVE: The sensory detection of food and food cues suppresses Agouti related peptide (AgRP) neuronal activity prior to consumption with greatest suppression occurring in response to highly caloric food or interoceptive energy need. However, the interoceptive mechanisms priming an appropriate AgRP neural response to external sensory information of food availability remain unexplored. Since hunger increases plasma ghrelin, we hypothesized that ghrelin receptor (GHSR) signalling on AgRP neurons is a key interoceptive mechanism integrating energy need with external sensory cues predicting caloric availability. METHODS: We used in vivo photometry to measure the effects of ghrelin administration or fasting on AgRP neural activity with GCaMP6s and dopamine release in the nucleus accumbens with GRAB-DA in mice lacking ghrelin receptors in AgRP neurons. RESULTS: The deletion of GHSR on AgRP neurons prevented ghrelin-induced food intake, motivation and AgRP activity. The presentation of food (peanut butter pellet) or a wooden dowel suppressed AgRP activity in fasted WT but not mice lacking GHSRs in AgRP neurons. Similarly, peanut butter and a wooden dowel increased dopamine release in the nucleus accumbens after ip ghrelin injection in WT but not mice lacking GHSRs in AgRP neurons. No difference in dopamine release was observed in fasted mice. Finally, ip ghrelin administration did not directly increase dopamine neural activity in the ventral tegmental area. CONCLUSIONS: Our results suggest that AgRP GHSRs integrate an interoceptive state of energy need with external sensory information to produce an optimal change in AgRP neural activity. Thus, ghrelin signalling on AgRP neurons is more than just a feedback signal to increase AgRP activity during hunger.


Assuntos
Ingestão de Alimentos , Grelina , Camundongos , Animais , Grelina/metabolismo , Proteína Relacionada com Agouti/metabolismo , Dopamina/metabolismo , Neurônios/metabolismo
3.
J Gastrointestin Liver Dis ; 32(3): 377-383, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37774211

RESUMO

BACKGROUND AND AIMS: Colorectal cancer has the third highest incidence and second highest mortality among all cancers worldwide. Although numerous studies investigating the associations between high red meat intake and risk of colorectal cancer have been published, the association between the intake of red meat and the risk of colorectal cancer in Asians remains unclear. We performed a systematic review and meta-analysis of cohort and case-control studies to estimate the association between red meat intake and colorectal cancer incidence rate between 2011-2021. METHOD: We searched PubMed database from 1 Jan 2011 to 21 July 2021. Prospective cohort studies and nested case-control studies that reported results on the association between red meat consumption and colorectal cancer were included in the meta-analysis. The outcome of interest was the association between the intake of red meat and the risk of colorectal cancer. We performed a meta-analysis to calculate the odds ratios (OR) with 95% confidence intervals (CI). RESULTS: A total of 5 studies enrolling 48,158 participants were included. The results showed no significant association between red meat intake and colorectal cancer risks (OR=1.38; 95%CI: 0.98-1.93). The aspect of the corresponding funnel plot suggested the presence of significant publication bias. Egger's test confirmed the significant asymmetry of the funnel plot (t = 9.3024, p = 0.0026). CONCLUSIONS: Contrary to many other meta-analyses, our study showed that intake of red meat was not associated with increased risk of colorectal cancer in East-Asians from China, Japan and South Korea. However, due to the limited number of included papers and the lack of confounders adjustments, our results warrant cautious interpretations.

4.
Structure ; 30(8): 1075-1087.e4, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35588733

RESUMO

G-protein-coupled receptors (GPCRs) are the largest human receptor family and involved in virtually every physiological process. One hallmark of their function is specific coupling to selected signaling pathways. The ability to tune this coupling would make development of receptors with new capabilities possible. Complexes of GPCRs and G-proteins have recently been resolved at high resolution, but this information was in only few cases harnessed for rational receptor engineering. Here, we demonstrate structure-guided optimization of light-activated OptoXRs. Our hypothesis was that incorporation of GPCR-Gα contacts would lead to improved coupling. We first evaluated structure-based alignments for chimeric receptor fusion. We then show in a light-activated ß2AR that including Gα contacts increased signaling 7- to 20-fold compared with other designs. In turn, contact elimination diminished function. Finally, this platform allowed optimization of a further OptoXR and spectral tuning. Our work exemplifies structure-based OptoXR development for targeted cell and network manipulation.


Assuntos
Proteínas de Ligação ao GTP , Receptores Acoplados a Proteínas G , Proteínas de Ligação ao GTP/metabolismo , Humanos , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/fisiologia
5.
Anticancer Agents Med Chem ; 14(5): 756-61, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24476313

RESUMO

The different types of cell death occurring in HCT116 colorectal cancer cell after the treatment of cisplatin, carboplatin, oxaliplatin, DMC, Pt(NH3)2(demethylcantharidin:DMC) and Pt(R,R-1,2-diaminocyclohexane: DACH)(DMC) were examined. Pt(NH3)2(DMC) and Pt(R,R-DACH)(DMC) are the two DMC-integrated platinum complexes:Pt(R,R-DACH)(DMC) with the same Pt moiety as oxaliplatin and Pt(NH3)2(DMC) akin to carboplatin. Using the light scattering properties of cells combined with propidium iodide (PI) red fluorescence to distinguish between early apoptotic and necrotic cells, the results confirmed that apoptosis, which triggered by cisplatin, carboplatin and oxaliplatin, was the major type of cell death, while the major DMC-induced cell death type was necrosis. The increase in the necrotic cell population was observed after Pt((NH3)2(DMC) treatment when compared with carboplatin; therefore, the DMC ligand in Pt(NH3)2(DMC) contributing to cell death was demonstrated. However, the DMC ligand in Pt(R,RDACH)( DMC) failed to elevate the necrotic cell population significantly in contrast to oxaliplatin, thus Pt(R,R-DACH) in Pt(R,RDACH)( DMC) dominantly contributed to cell death. The IC50 value (antiproliferative activity) reflects the net effect of drugs on cell proliferation resulting from inhibition of cell growth and division, and induction of cell death. The sub-G1 populations representing the sum of the amounts of late apoptotic cells and necrotic cells after the treatment of cispatin, carboplatin, oxaliplatin, DMC, Pt(NH3)2(DMC) and Pt(R,R-DACH)(DMC) were found to be not correlated with the corresponding IC50 values;therefore, the rate of cell growth and division inhibition rather than the rate of induction of cell death dictated to the IC50 values. This combined analysis of IC50 values and the sub-G1 population data also reveals that the platinum compounds containing R,R-DACH are most efficient in inhibiting cell growth and division, while carboplatin induces cell death most rapidly. When the Pt-DNA adducts are believed to be major cytotoxic species, the combined analysis of the IC50 values and the sub-G1 population data infers that the R,R-DACH-Pt-1,2-d(GpG) intrastrand cross-links caused by oxaliplatin treatment are more effective in inducing cell growth and division inhibition, while the (NH3)2Pt-1,3- d(GpXpG) intrastrand cross-links caused by carboplatin treatment can trigger cell death more rapidly. The rate of cell growth and division inhibition and the cell death rate induced by the main cisplatin-DNA adducts:(NH3)2Pt-1,2-d(GpG) intrastrand cross-links lie in between.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cantaridina/análogos & derivados , Complexos de Coordenação/farmacologia , Compostos Organoplatínicos/farmacologia , Platina , Antineoplásicos/química , Cantaridina/química , Cantaridina/farmacologia , Carboplatina/farmacologia , Cisplatino/farmacologia , Complexos de Coordenação/química , Adutos de DNA/metabolismo , Células HCT116 , Humanos , Concentração Inibidora 50 , Luz , Necrose/metabolismo , Imagem Óptica , Compostos Organoplatínicos/química , Piridinas/farmacologia , Espalhamento de Radiação
6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-581615

RESUMO

Reccent investigations demonstrated that genetically modified tumor cells could be used as vaccines against cancer. In this light, we introduced human interleukin -2 (IL-2) gene into a poorly immunogenic rat fibrosarcoma cell line WBT, a human lung abenocarcinoma cell line AGZY and a highly metastatie sub - cell line Anip973 derived from AGZY. The transduced cells showed no obvious changes in morphology, growth and colony - forming ability in soft agar.Transduction with IL-2 gene rendered the cells more sensitive than the parental cells and cells transduced with NeoR gene alone to the lysis by cytotoxic lymphocytes. High levels of IFN and TNF were detected in the supernatants of cocultured lymphocytes and tumor cells containing IL-2 gene. Tumorigenicity of WBT/IL-2 cells was greatly reduced in syngeneic rats. Metastatic capacity of Anip973 in nude mice was blocked by the transduction of IL-2 gene, but not the transduction of NeoR gene alone. Inoculation of WBT/IL-2 cells conferred rats resistance to the challenge of parental WBT cells.Splenocytes from WBT/IL-2-inoculated rats restimulated with WBT cells in vitro showed high CTL activity against WBT cells. Our results demonstrated the potential application of tumor cells transduced with IL— gene as active vaccine against cancer.

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