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1.
Nature ; 610(7932): 461-466, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36261547

RESUMEN

Stephan's Quintet (SQ, co-moving radial distance = 85 ± 6 Mpc, taken from the NASA/IPAC Extragalactic Database (NED)1) is unique among compact groups of galaxies2-12. Observations have previously shown that interactions between multiple members, including a high-speed intruder galaxy currently colliding into the intragroup medium, have probably generated tidal debris in the form of multiple gaseous and stellar filaments6,8,13, the formation of tidal dwarfs7,14,15 and intragroup-medium starbursts16, as well as widespread intergalactic shocked gas5,10,11,17. The details and timing of the interactions and collisions remain poorly understood because of their multiple nature18,19. Here we report atomic hydrogen (H I) observations in the vicinity of SQ with a smoothed sensitivity of 1σ = 4.2 × 1016 cm-2 per channel (velocity bin-width Δv = 20 km s-1; angular resolution = 4'), which are about two orders of magnitude deeper than previous observations8,13,20,21. The data show a large H I structure (with linear scale of around 0.6 Mpc) encompassing an extended source of size approximately 0.4 Mpc associated with the debris field and a curved diffuse feature of length around 0.5 Mpc attached to the south edge of the extended source. The diffuse feature was probably produced by tidal interactions in early stages of the formation of SQ (>1 Gyr ago), although it is not clear how the low-density H I gas (NH i ≲ 1018 cm-2) can survive the ionization by the intergalactic ultraviolet background on such a long time scale. Our observations require a rethinking of properties of gas in outer parts of galaxy groups and demand complex modelling of different phases of the intragroup medium in simulations of group formation.

2.
Semin Cell Dev Biol ; 121: 53-62, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33867214

RESUMEN

In rodents and humans, the major cellular events at spermatogenesis include self-renewal of spermatogonial stem cells and undifferentiated spermatogonia via mitosis, commitment of spermatogonia to differentiation and transformation to spermatocytes, meiosis, spermiogenesis, and the release of spermatozoa at spermiation. While details of the morphological changes during these cellular events have been delineated, knowledge gap exists between the morphological changes in the seminiferous epithelium and the underlying molecular mechanism(s) that regulate these cellular events. Even though many of the regulatory proteins and biomolecules that modulate spermatogenesis are known based on studies using genetic models, the underlying regulatory mechanism(s), in particular signaling pathways/proteins, remain unexplored since much of the information regarding the signaling regulation is unknown. Studies in the past decade, however, have unequivocally demonstrated that the testis is using several signaling proteins and/or pathways to regulate multiple cellular events to modulate spermatogenesis. These include mTORC1/rpS6/Akt1/2 and p-FAK-Y407. While selective inhibitors and/or agonists and antagonists are available to examine some of these signaling proteins, their use have limitations due to their specificities and also potential systemic cytotoxicity. On the other hand, the use of genetic models has had profound implications for our understanding of the molecular regulation of spermatogenesis, and these knockout (null) models have also revealed the factors that are critical for spermatogenesis. Nonetheless, additional studies using in vitro and in vivo models are necessary to unravel the signaling pathways involved in regulating seminiferous epithelial cycle. Emerging data from studies, such as the use of the adjudin pharmaceutical/toxicant model, have illustrated that this non-hormonal male contraceptive drug is utilizing specific signaling pathways/proteins to induce specific defects in spermatogenesis, yielding mechanistic insights on the regulation of spermatogenesis. We sought to review these recent data in this article, highlighting an interesting approach that can be considered for future studies.


Asunto(s)
Hidrazinas/uso terapéutico , Indazoles/uso terapéutico , Diana Mecanicista del Complejo 1 de la Rapamicina/inmunología , Espermatogénesis/inmunología , Animales , Humanos , Hidrazinas/farmacología , Indazoles/farmacología , Masculino , Transducción de Señal
3.
Semin Cell Dev Biol ; 121: 40-52, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33879391

RESUMEN

In adult rat testes, the basement membrane is structurally constituted by laminin and collagen chains that lay adjacent to the blood-testis barrier (BTB). It plays a crucial scaffolding role to support spermatogenesis. On the other hand, laminin-333 comprised of laminin-α3/ß3/γ3 at the apical ES (ectoplasmic specialization, a testis-specific cell-cell adherens junction at the Sertoli cell-step 8-19 spermatid interface) expressed by spermatids serves as a unique cell adhesion protein that forms an adhesion complex with α6ß1-integrin expressed by Sertoli cells to support spermiogenesis. Emerging evidence has shown that biologically active fragments are derived from basement membrane and apical ES laminin chains through proteolytic cleavage mediated by matrix metalloproteinase 9 (MMP9) and MMP2, respectively. Two of these laminin bioactive fragments: one from the basement membrane laminin-α2 chain called LG3/4/5-peptide, and one from the apical ES laminin-γ3 chain known as F5-peptide, are potent regulators that modify cell adhesion function at the Sertoli-spermatid interface (i.e., apical ES) but also at the Sertoli cell-cell interface designated basal ES at the blood-testis barrier (BTB) with contrasting effects. These findings not only highlight the physiological significance of these bioactive peptides that create a local regulatory network to support spermatogenesis, they also open a unique area of research. For instance, it is likely that several other bioactive peptides remain to be identified. These bioactive peptides including their downstream signaling proteins and cascades should be studied collectively in future investigations to elucidate the underlying mechanism(s) by which they coordinate with each other to maintain spermatogenesis. This is the goal of this review.


Asunto(s)
Redes Reguladoras de Genes/genética , Laminina/inmunología , Espermatogénesis/inmunología , Testículo/inmunología , Animales , Masculino , Ratones , Ratas
4.
Semin Cell Dev Biol ; 121: 125-132, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34325997

RESUMEN

Studies have demonstrated that biologically active fragments are generated from the basement membrane and the Sertoli cell-spermatid adhesion site known as apical ectoplasmic specialization (apical ES, a testis-specific actin-based anchoring junction) in the rat testis. These bioactive fragments or peptides are produced locally across the seminiferous epithelium through proteolytic cleavage of constituent proteins at the basement membrane and the apical ES. Studies have shown that they are being used to modulate and coordinate cellular functions across the seminiferous epithelium during different stages of the epithelial cycle of spermatogenesis. In this review, we briefly summarize recent findings based on studies using rat testes as a study model regarding the role of these bioactive peptides that serve as a local regulatory network to support spermatogenesis. We also used scRNA-Seq transcriptome datasets in the public domain for OA (obstructive azoospermia) and NAO (non-obstructive azoospermia) human testes versus testes from normal men for analysis in this review. It was shown that there are differential expression of different collagen chains and laminin chains in these testes, suggesting the possibility of a similar local regulatory network in the human testis to support spermatogenesis, and the possible disruption of such network in men is associated with OA and/or NOA.


Asunto(s)
Colágeno/metabolismo , Perfilación de la Expresión Génica/métodos , Laminina/metabolismo , Análisis de la Célula Individual/métodos , Espermatogénesis/genética , Animales , Humanos , Masculino , Ratones , Persona de Mediana Edad , Ratas
5.
Semin Cell Dev Biol ; 121: 99-113, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34059418

RESUMEN

Few reports are found in the literature regarding the role of planar cell polarity (PCP) in supporting spermatogenesis in the testis. Yet morphological studies reported decades earlier have illustrated the directional alignment of polarized developing spermatids, most notably step 17-19 spermatids in stage V-early VIII tubules in the testis, across the plane of the epithelium in seminiferous tubules of adult rats. Such morphological features have unequivocally demonstrated the presence of PCP in developing spermatids, analogous to the PCP noted in hair cells of the cochlea in mammals. Emerging evidence in recent years has shown that Sertoli and germ cells express numerous PCP proteins, mostly notably, the core PCP proteins, PCP effectors and PCP signaling proteins. In this review, we discuss recent findings in the field regarding the two core PCP protein complexes, namely the Van Gogh-like 2 (Vangl2)/Prickle (Pk) complex and the Frizzled (Fzd)/Dishevelled (Dvl) complex. These findings have illustrated that these PCP proteins exert their regulatory role to support spermatogenesis through changes in the organization of actin and microtubule (MT) cytoskeletons in Sertoli cells. For instance, these PCP proteins confer PCP to developing spermatids. As such, developing haploid spermatids can be aligned and orderly packed within the limited space of the seminiferous tubules in the testes for the production of sperm via spermatogenesis. Thus, each adult male in the mouse, rat or human can produce an upward of 30, 50 or 300 million spermatozoa on a daily basis, respectively, throughout the adulthood. We also highlight critical areas of research that deserve attention in future studies. We also provide a hypothetical model by which PCP proteins support spermatogenesis based on recent studies in the testis. It is conceivable that the hypothetical model shown here will be updated as more data become available in future years, but this information can serve as the framework by investigators to unravel the role of PCP in spermatogenesis.


Asunto(s)
Polaridad Celular/fisiología , Citoesqueleto/metabolismo , Receptores de Fenciclidina/metabolismo , Espermatogénesis/genética , Testículo/fisiología , Animales , Drosophila , Masculino
6.
Artículo en Inglés | MEDLINE | ID: mdl-38826136

RESUMEN

Per- and polyfluoroalkyl substances (PFAS) are a family of "forever chemicals" including PFOS (perfluorooctane sulfonate). These toxic chemicals do not break down in the environment nor in our bodies. In the human body, PFOS and PFOA (perfluoroctanoic acid) have a half-life (T1/2) of about 4-5 years so low daily consumption of these chemicals can accumulate in the human body to a harmful level over a long period. Although the use of PFOS in consumer products was banned in the U.S. in 2022/2023, this forever chemical remains detectable in our tap water and food products. Every American tested has a high level of PFAS in their blood (https://cleanwater.org/pfas-forever-chemicals). In this report, we used a Sertoli cell blood-testis barrier (BTB) model with primary Sertoli cells cultured in vitro with an established functional tight junction (TJ)-permeability barrier that mimicked the BTB in vivo. Treatment of Sertoli cells with PFOS was found to perturb the TJ-barrier, which was the result of cytoskeletal disruption across the cell cytoplasm, disrupting actin and microtubule polymerization. These changes thus affected the proper localization of BTB-associated proteins at the BTB. Using RNA-Seq transcriptome profiling, bioinformatics analysis, and pertinent biochemical and cell biology techniques, it was discovered that PFOS-induced Sertoli cell toxicity through the c-Jun N-terminal kinase (JNK; also known as stress-activated protein kinase, SAPK) and its phosphorylated/active form p-JNK signaling pathway. More importantly, KB-R7943 mesylate (KB), a JNK/p-JNK activator, was capable of blocking PFOS-induced Sertoli cell injury, supporting the notion that PFOS-induced cell injury can possibly be therapeutically managed.

7.
Mol Biol Evol ; 40(3)2023 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-36806940

RESUMEN

White-blooded Antarctic icefishes, a family within the adaptive radiation of Antarctic notothenioid fishes, are an example of extreme biological specialization to both the chronic cold of the Southern Ocean and life without hemoglobin. As a result, icefishes display derived physiology that limits them to the cold and highly oxygenated Antarctic waters. Against these constraints, remarkably one species, the pike icefish Champsocephalus esox, successfully colonized temperate South American waters. To study the genetic mechanisms underlying secondarily temperate adaptation in icefishes, we generated chromosome-level genome assemblies of both C. esox and its Antarctic sister species, Champsocephalus gunnari. The C. esox genome is similar in structure and organization to that of its Antarctic congener; however, we observe evidence of chromosomal rearrangements coinciding with regions of elevated genetic divergence in pike icefish populations. We also find several key biological pathways under selection, including genes related to mitochondria and vision, highlighting candidates behind temperate adaptation in C. esox. Substantial antifreeze glycoprotein (AFGP) pseudogenization has occurred in the pike icefish, likely due to relaxed selection following ancestral escape from Antarctica. The canonical AFGP locus organization is conserved in C. esox and C. gunnari, but both show a translocation of two AFGP copies to a separate locus, previously unobserved in cryonotothenioids. Altogether, the study of this secondarily temperate species provides an insight into the mechanisms underlying adaptation to ecologically disparate environments in this otherwise highly specialized group.


Asunto(s)
Adaptación Fisiológica , Perciformes , Animales , Regiones Antárticas , Peces/genética , Perciformes/genética , Genómica , Proteínas Anticongelantes
8.
Hum Mol Genet ; 31(3): 321-333, 2022 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-33438010

RESUMEN

During human spermatogenesis, germ cells undergo dynamic changes in chromatin organization/re-packaging and in transcriptomes. In order to better understand the underlying mechanism(s), scATAC-Seq of 5376 testicular cells from 3 normal men were performed. Data were analyzed in parallel with the scRNA-Seq data of human testicular cells. In all, 10 germ cell types associated with spermatogenesis and 6 testicular somatic cell types were identified, along with 142 024 peaks located in promoter, genebody and CpG Island. We had examined chromatin accessibility of all chromosomes, with chromosomes 19 and 17 emerged as the leading chromosomes that displayed high chromatin accessibility. In accessible chromatin regions, transcription factor-binding sites were identified and specific motifs with high frequencies at different spermatogenesis stages were detected, including CTCF, BORIS, NFY, DMRT6, EN1, ISL1 and GLI3. Two most remarkable observations were noted. First, TLE3 was specifically expressed in differentiating spermatogonia. Second, PFN4 was found to be involved in actin cytoskeletal organization during meiosis. More important, unique regions upstream of PFN4 and TLE3 were shown to display high accessibility, illustrating their significance in supporting human spermatogenesis.


Asunto(s)
Secuenciación de Inmunoprecipitación de Cromatina , Cromatina , Cromatina/genética , Cromatina/metabolismo , Humanos , Masculino , Meiosis , Espermatogénesis/genética , Espermatogonias/metabolismo
9.
Reprod Biol Endocrinol ; 22(1): 36, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570783

RESUMEN

Microtubule-associated protein 1a (Map1a) is a microtubule (MT) regulatory protein that binds to the MT protofilaments in mammalian cells to promote MT stabilization. Maps work with MT cleavage proteins and other MT catastrophe-inducing proteins to confer MT dynamics to support changes in the Sertoli cell shape to sustain spermatogenesis. However, no functional studies are found in the literature to probe its role in spermatogenesis. Using an RNAi approach, coupled with the use of toxicant-induced testis (in vivo)- and Sertoli cell (in vitro)-injury models, RNA-Seq analysis, transcriptome profiling, and relevant bioinformatics analysis, immunofluorescence analysis, and pertinent biochemical assays for cytoskeletal organization, we have delineated the functional role of Map1a in Sertoli cells and testes. Map1a was shown to support MT structural organization, and its knockdown (KD) also perturbed the structural organization of actin, vimentin, and septin cytoskeletons as these cytoskeletons are intimately related, working in concert to support spermatogenesis. More importantly, cadmium-induced Sertoli cell injury that perturbed the MT structural organization across the cell cytoplasm was associated with disruptive changes in the distribution of Map1a and a surge in p-p38-MAPK (phosphorylated p38-mitogen-activated protein kinase) expression but not total p38-MAPK. These findings thus support the notion that p-p38-MAPK activation is involved in cadmium-induced Sertoli cell injury. This conclusion was supported by studies using doramapimod, a specific p38-MAPK phosphorylation (activation) inhibitor, which was capable of restoring the cadmium-induced disruptive structural organization of MTs across the Sertoli cell cytoplasm. In summary: this study provides mechanistic insights regarding restoration of toxicant-induced Sertoli cell and testis injury and male infertility.


Asunto(s)
Actinas , Células de Sertoli , Ratas , Animales , Masculino , Actinas/metabolismo , Células de Sertoli/metabolismo , Cadmio , Ratas Sprague-Dawley , Barrera Hematotesticular/metabolismo , Microtúbulos/metabolismo , Testículo/metabolismo , Espermatogénesis/fisiología , Mamíferos
10.
J Endocrinol Invest ; 47(3): 547-555, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37768525

RESUMEN

PURPOSE: This research was performed to evaluate the relationship between hypertension (HTN) and abdominal obesity index in patients with type 2 diabetes mellitus (T2DM). METHODS: Totally 1657 participants with T2DM (mean age 54 ± 12 years; 38.02% female) were enrolled. They were divided into the groups of HTN (n = 775) and non-HTN (n = 882). Anthropometric and biochemical indicators were measured and collected. A bioelectrical impedance analyzer was used to measure visceral and subcutaneous fat areas. RESULTS: Compared with the HTN group, the non-HTN group had a lower level of Chinese visceral adiposity index (CVAI) (p < 0.001). Meanwhile, among tertiles of CVAI, as CVAI increased, the proportion of patients with HTN increased, which was 33.51%, 44.30%, and 62.50%, respectively. CVAI was shown to have a significant positive correlation with HTN. (r = 0.258, p < 0.001). CVAI was independently related to an elevated risk of HTN by binary logistic regression analyses, and the OR was (95% CI) 1.013 (1.010-1.016, p < 0.001) after adjustment. The area under the receiver operating characteristic curve (AUC) of CVAI predicted HTN in T2DM patients was greater than those of other abdominal obesity indices (p < 0.001). CONCLUSION: We found that CVAI was highly positively correlated with HTN in T2DM. Compared with other indices of abdominal obesity, such as WC, BMI, WHR, VAI, and LAP, the CVAI showed superior discriminative ability in T2DM complicated with HTN. Therefore, more attention should be paid to CVAI in T2DM.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hipertensión , Obesidad Mórbida , Humanos , Femenino , Adulto , Persona de Mediana Edad , Anciano , Masculino , Obesidad Abdominal/complicaciones , Obesidad Abdominal/diagnóstico , Adiposidad , Índice de Masa Corporal , Obesidad/complicaciones , Hipertensión/complicaciones , Hipertensión/diagnóstico , Hipertensión/epidemiología , Obesidad Mórbida/complicaciones , China/epidemiología
11.
J Endocrinol Invest ; 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38795312

RESUMEN

BACKGROUND: The prevalence of diabetic dyslipidemia has gradually increased worldwide and individuals with hypertriglyceridemia often have a high polygenic burden of triglyceride (TG)-increasing variants. However, the contribution of genetic variants to dyslipidemia in patients with type 2 diabetes (T2D) remains limited. Therefore, in this study, we aimed to investigate the genetic characteristics of longitudinal changes in TG levels among patients with T2D and summarize the genetic effects of polygenic risk score (PRS) on TG trajectory and risk of diabetic complications. METHODS: We conducted a case-control study. A total of 11,312 patients with T2D with longitudinal TG and genetic data were identified from a large hospital database in Taiwan. We then performed a genome-wide association study and calculated the relative PRS. RESULTS: In total, 21 single-nucleotide polymorphisms (SNPs) related to TG trajectory were identified and yielded an area under the receiver operating characteristic curve (ROC) of 0.712 for high TG trajectory risk among Taiwanese patients with T2D. A cumulative genetic effect was observed for high TG trajectory, even when considering the adherence of a lipid-lowering agent in stratified analysis. An increased PRS increases high TG trajectory risk in a logistic regression model (odds ratio = 1.55; 95% confidence interval [CI] = 1.31-1.83 in the validation cohort). The TG-specific PRS was associated with the risk of diabetic microvascular complications, including diabetic retinopathy and nephropathy (with hazard ratios of 1.11 [95% CI = 1.01-1.21, P = 0.027] and 1.05 [95% CI = 1.01-1.1, P = 0.018], respectively). CONCLUSIONS: This study may contribute to the identification of patients with T2D who are at risk of abnormal TG levels and diabetic microvascular complications using polygenic information.

12.
Zhonghua Yi Xue Za Zhi ; 104(21): 1979-1986, 2024 Jun 04.
Artículo en Zh | MEDLINE | ID: mdl-38825941

RESUMEN

Objective: To analyze the efficacy of alternate titanium clip closure in preventing postoperative complications for patients with gastric mucosal lesions after endoscopic submucosal dissection (ESD). Methods: Clinical data of patients with gastric mucosal lesions who underwent ESD in the Department of Gastroenterology, Zhongda Hospital, Southeast University, were retrospectively collected from January 1, 2013 to August 31, 2023. According to the postoperative wound closure status, the patients were divided into completely closed group (complete closure of ESD wounds using alternate titanium clip closure), partially closed group (partial closure of ESD wounds), and unclosed group (without use of clips for treatment of ESD wounds). The incidence of postoperative complications as well as wound healing at 1 month and 3 months after surgery were compared among three groups, and the factors related to delayed bleeding after ESD for gastric mucosal lesions were analyzed through multiple logistic regression analysis. Results: A total of 846 patients were included, 430 cases in the completely closed group, including 300 males and 130 females, age [M (Q1, Q3)] was 65(56, 72) years old; one hundred and nine cases in unclosed group, including 78 males and 31 females, aged 66 (60, 71) years; and 307 cases in the partially closed group, including 214 males and 93 females, aged 66 (59, 71) years. The difference in the rate of delayed postoperative bleeding between the completely closed group [2.1% (9/430)] and the unclosed group [5.5% (6/109)] was not statistically significant (P=0.072), but both were lower than that of the partially closed group [9.4% (29/307), P<0.05)]. Further stratified analysis showed that, for the lesions located in the lower 1/3 of the stomach, the rate of postoperative bleeding was lower in the completely closed group than in the partially closed and unclosed groups [0.9% (2/222) vs 11.4% (4/35) vs 9.5% (7/74), respectively, P<0.001]. For lesions≥50 mm in length, the rate of postoperative bleeding was lower in the completely closed group than that in the partially closed and unclosed group[0 vs 11.8% (2/17) vs 20.5% (15/73), respectively, P=0.004]. The incidence of postoperative abdominal pain in the completely closed group [84.2% (363/430)] was lower than that in the unclosed group [97.2% (106/109)] and the partially closed group [95.4% (293/307), both P<0.001)]. The score of postoperative abdominal pain in the completely closed group [0 (0, 1)], was lower than that in the unclosed group [3 (2, 3)], and that in the partially closed group [2 (1, 3)] (both P<0.001). The wound healing rate of the completely closed group [80% (176/220)] was higher than that of the unclosed group [52.3% (33/63)] and the partially closed group [52.2% (83/159)] at 1 month postoperatively (both P<0.001); the healing rate of all three groups reached 100% at 3 months postoperatively. Multiple logistic regression analysis showed that the presence of ulcers or scars on the surface of the lesion (OR=2.930, 95%CI:1.503-5.712, P=0.002), and the diameter (OR=1.031, 95%CI:1.015-1.047,P<0.001) were related factors for postoperative bleeding. Conclusions: The alternate titanium clip closure surgery can reduce postoperative abdominal pain and shorten wound healing time in patients with gastric mucosal lesions after ESD surgery. The risk of postoperative bleeding can be reduced for lesions with a diameter≥50 mm and located in the lower 1/3 of the stomach.


Asunto(s)
Resección Endoscópica de la Mucosa , Mucosa Gástrica , Complicaciones Posoperatorias , Humanos , Resección Endoscópica de la Mucosa/efectos adversos , Resección Endoscópica de la Mucosa/métodos , Masculino , Anciano , Femenino , Mucosa Gástrica/cirugía , Complicaciones Posoperatorias/prevención & control , Persona de Mediana Edad , Instrumentos Quirúrgicos , Neoplasias Gástricas/cirugía , Titanio , Cicatrización de Heridas , Gastroscopía
13.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(7): 647-653, 2024 Jul 12.
Artículo en Zh | MEDLINE | ID: mdl-38955750

RESUMEN

Objective: To investigate the relationship between arousal threshold (ArTH) and hypertension in patients with obstructive sleep apnea hypopnea syndrome (OSA). Methods: This study recruited 648 patients diagnosed with OSA at the Sleep Center of the Second Affiliated Hospital of Soochow University from January 2020 to August 2021, including 569 males and 79 females, aged 42(35,52) years. The basic demographic information and clinical data of all patients were collected, including blood pressure measurement, and relevant questionnaire scores, and nocturnal polysomnography (PSG) parameters. A clinical predictive model based on sleep apnea hypopnea index (AHI), lowest pulse oxygen saturation (LSpaO2) and hypopnea ratio (FHypopneas) was used to access the arousal threshold of OSA patients. Patients were divided into OSA group and OSA with hypertension group according to whether they were combined with hypertension. The differences in the above indexes between the two groups were analyzed to explore the relationship between arousal threshold and hypertension in OSA patients, using a binary logistic stepwise regression analysis. Results: A total of 648 OSA patients were enrolled, including 415 in the OSA with hypertension group and 233 in the OSA group. Compared with OSA group, OSA with hypertension group had older age, higher body mass index (BMI), higher blood pressure at bedtime and at awakening, higher AHI and lower proportion of hypopnea (all P<0.05). There were no significant differences between other general data and PSG parameters (all P>0.05). The proportion of patients with low arousal threshold (AHI<30 events per hour, LSpO2>82.5%, Fhypopneas>58.3%) in OSA with hypertension group was lower, and the proportion of phenotypic patients with low arousal threshold was significantly lower (30.1% vs. 52.4% P<0.001). Binary logistic stepwise regression analysis showed that the high arousal threshold (OR=1.930, 95%CI:1.326-2.808, P=0.001) was an independent risk factor for OSA complicated with hypertension. Conclusion: The arousal threshold is associated with the development of hypertension in OSA patients, and OSA patients with a high arousal threshold have a higher risk of developing hypertension.


Asunto(s)
Nivel de Alerta , Hipertensión , Polisomnografía , Apnea Obstructiva del Sueño , Humanos , Apnea Obstructiva del Sueño/fisiopatología , Apnea Obstructiva del Sueño/complicaciones , Femenino , Masculino , Persona de Mediana Edad , Hipertensión/fisiopatología , Hipertensión/complicaciones , Adulto , Factores de Riesgo , Presión Sanguínea , Modelos Logísticos , Saturación de Oxígeno , Encuestas y Cuestionarios
14.
Crit Rev Biochem Mol Biol ; 56(3): 236-254, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33761828

RESUMEN

It is almost five decades since the discovery of the hypothalamic-pituitary-testicular axis. This refers to the hormonal axis that connects the hypothalamus, pituitary gland and testes, which in turn, regulates the production of spermatozoa through spermatogenesis in the seminiferous tubules, and testosterone through steroidogenesis by Leydig cells in the interstitium, of the testes. Emerging evidence has demonstrated the presence of a regulatory network across the seminiferous epithelium utilizing bioactive molecules produced locally at specific domains of the epithelium. Studies have shown that biologically active fragments are produced from structural laminin and collagen chains in the basement membrane. Additionally, bioactive peptides are also produced locally in non-basement membrane laminin chains at the Sertoli-spermatid interface known as apical ectoplasmic specialization (apical ES, a testis-specific actin-based anchoring junction type). These bioactive peptides are derived from structural laminins and/or collagens at the corresponding sites through proteolytic cleavage by matrix metalloproteinases (MMPs). They in turn serve as autocrine and/or paracrine factors to modulate and coordinate cellular events across the epithelium by linking the apical and basal compartments, the apical and basal ES, the blood-testis barrier (BTB), and the basement membrane of the tunica propria. The cellular events supported by these bioactive peptides/fragments include the release of spermatozoa at spermiation, remodeling of the immunological barrier to facilitate the transport of preleptotene spermatocytes across the BTB, and the transport of haploid spermatids across the epithelium to support spermiogenesis. In this review, we critically evaluate these findings. Our goal is to identify research areas that deserve attentions in future years. The proposed research also provides the much needed understanding on the biology of spermatogenesis supported by a local network of regulatory biomolecules.


Asunto(s)
Barrera Hematotesticular/metabolismo , Colágeno/metabolismo , Epitelio Seminífero/metabolismo , Espermatogénesis , Espermatozoides/metabolismo , Animales , Humanos , Células Intersticiales del Testículo/metabolismo , Masculino , Células de Sertoli/metabolismo , Transducción de Señal
15.
Clin Infect Dis ; 77(3): 480-489, 2023 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-36949605

RESUMEN

BACKGROUND: Respiratory syncytial virus (RSV) is shown to cause substantial morbidity, hospitalization, and mortality in infants and older adults. Population-level modeling of RSV allows to estimate the full burden of disease and the potential epidemiological impact of novel prophylactics. METHODS: We modeled the RSV epidemiology in the United States across all ages using a deterministic compartmental transmission model. Population-level symptomatic RSV acute respiratory tract infection (ARI) cases were projected across different natural history scenarios with and without vaccination of adults aged ≥60 years. The impact of vaccine efficacy against ARIs, infectiousness and vaccine coverage on ARI incidence were assessed. The impact on medical attendance, hospitalization, complications, death, and other outcomes was also derived. RESULTS: Without a vaccine, we project 17.5-22.6 million symptomatic RSV ARI cases annually in adults aged ≥18 years in the US, with 3.6-4.8 million/year occurring in adults aged ≥60 years. Modeling indicates that up to 2.0 million symptomatic RSV-ARI cases could be prevented annually in ≥60-year-olds with a hypothetical vaccine (70% vaccine efficacy against symptomatic ARI and 60% vaccine coverage) and that up to 0.69 million/year could be prevented in the nonvaccinated population, assuming 50% vaccine impact on infectiousness. CONCLUSIONS: The model provides estimated burden of RSV in the US across all age groups, with substantial burden projected specifically in older adults. Vaccination of adults aged ≥60 years could significantly reduce the burden of disease in this population, with additional indirect effect in adults aged <60 years due to reduced transmissibility.


Asunto(s)
Infecciones por Virus Sincitial Respiratorio , Vacunas contra Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Adolescente , Adulto , Anciano , Humanos , Hospitalización , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/prevención & control , Estados Unidos/epidemiología , Vacunación , Persona de Mediana Edad
16.
Phys Rev Lett ; 130(12): 122502, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37027859

RESUMEN

The excited states of N=44 ^{74}Zn were investigated via γ-ray spectroscopy following ^{74}Cu ß decay. By exploiting γ-γ angular correlation analysis, the 2_{2}^{+}, 3_{1}^{+}, 0_{2}^{+}, and 2_{3}^{+} states in ^{74}Zn were firmly established. The γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+}, 3_{1}^{+}, and 2_{3}^{+} states were measured, allowing for the extraction of relative B(E2) values. In particular, the 2_{3}^{+}→0_{2}^{+} and 2_{3}^{+}→4_{1}^{+} transitions were observed for the first time. The results show excellent agreement with new microscopic large-scale shell-model calculations, and are discussed in terms of underlying shapes, as well as the role of neutron excitations across the N=40 gap. Enhanced axial shape asymmetry (triaxiality) is suggested to characterize ^{74}Zn in its ground state. Furthermore, an excited K=0 band with a significantly larger softness in its shape is identified. A shore of the N=40 "island of inversion" appears to manifest above Z=26, previously thought as its northern limit in the chart of the nuclides.

17.
Phys Rev Lett ; 131(20): 201801, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-38039482

RESUMEN

A new dark sector antibaryon, denoted ψ_{D}, could be produced in decays of B mesons. This Letter presents a search for B^{+}→ψ_{D}+p (and the charge conjugate) decays in e^{+}e^{-} annihilations at 10.58 GeV, using data collected in the BABAR experiment. Data corresponding to an integrated luminosity of 398 fb^{-1} are analyzed. No evidence for a signal is observed. Branching fraction upper limits in the range from 10^{-7}-10^{-5} are obtained at 90% confidence level for masses of 1.0

18.
Clin Radiol ; 78(8): 584-589, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37244824

RESUMEN

AIM: To investigate the feasibility of using deep learning (DL) to differentiate normal from abnormal (or scarred) kidneys using technetium-99m dimercaptosuccinic acid (99mTc-DMSA) single-photon-emission computed tomography (SPECT) in paediatric patients. MATERIAL AND METHODS: Three hundred and one 99mTc-DMSA renal SPECT examinations were reviewed retrospectively. The 301 patients were split randomly into 261, 20, and 20 for training, validation, and testing data, respectively. The DL model was trained using three-dimensional (3D) SPECT images, two-dimensional (2D) maximum intensity projections (MIPs), and 2.5-dimensional (2.5D) MIPs (i.e., transverse, sagittal, and coronal views). Each DL model was trained to determine renal SPECT images into either normal or abnormal. Consensus reading results by two nuclear medicine physicians served as the reference standard. RESULTS: The DL model trained by 2.5D MIPs outperformed that trained by either 3D SPECT images or 2D MIPs. The accuracy, sensitivity, and specificity of the 2.5D model for the differentiation between normal and abnormal kidneys were 92.5%, 90% and 95%, respectively. CONCLUSION: The experimental results suggest that DL has the potential to differentiate normal from abnormal kidneys in children using 99mTc-DMSA SPECT imaging.


Asunto(s)
Aprendizaje Profundo , Enfermedades Renales , Humanos , Niño , Estudios Retrospectivos , Riñón/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único/métodos , Ácido Dimercaptosuccínico de Tecnecio Tc 99m , Radiofármacos
19.
J Dairy Sci ; 106(12): 8611-8626, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37641244

RESUMEN

We evaluated the effects of supplementing bacterial direct-fed microbial (DFM) on performance, apparent total-tract digestibility, rumen fermentation, and immune parameters of lactating dairy cows. One hundred fourteen multiparous Holstein cows (41 ± 7 DIM) were used in a randomized complete block design with an experiment comprising 14 d of a covariate (pre-experimental sample and data collection) and 91 d of an experimental period. Cows were blocked based on energy-corrected milk (ECM) yield during the covariate period and the following treatments were randomly assigned within each block: (1) control (CON), corn silage-based total mixed ration without DFM; (2) PRO-A, basal diet top-dressed with a mixture of Lactobacillus animalis and Propionibacterium freudenreichii at 3 × 109 cfu/d; and 3) PRO-B, basal diet top-dressed with a mixture of L. animalis, P. freudenreichii, Bacillus subtilis, and Bacillus licheniformis at 11.8 × 109 cfu/d. Milk yield, dry matter intake (DMI), and body weight were measured daily, while milk samples for component analysis were taken on 2 consecutive days of each week of data collection. Feces, urine, rumen, and blood samples were taken during the covariate period, wk 4, 7, 10, and 13 for estimation of digestibility, N-partitioning, rumen fermentation, plasma nutrient status and immune parameters. Treatments had no effect on DMI and milk yield. Fat-corrected milk (3.5% FCM) and milk fat yield were improved with PRO-B, while milk fat percent and feed efficiency (ECM/DMI) tended to increase with PRO-B compared with PRO-A and CON. Crude fat digestibility was greater with PRO-B compared with CON. Feeding CON and PRO-A resulted in higher total volatile fatty acid concentration relative to PRO-B. Percentage of neutrophils tended to be reduced with PRO-A compared with CON and PRO-B. The mean fluorescence intensity (MFI) of anti-CD44 antibody on granulocytes tended to be higher in PRO-B compared with CON. The MFI of anti-CD62L antibody on CD8+ T cells was lower in PRO-A than PRO-B, with PRO-A also showing a tendency to be lower than CON. This study indicates the potential of DFM to improve fat digestibility with consequential improvement in fat corrected milk yield, feed efficiency and milk fat yield by lactating dairy cows. The study findings also indicate that dietary supplementation with DFM may augment immune parameters or activation of immune cells, including granulocytes and T cells; however, the overall effects on immune parameters are inconclusive.


Asunto(s)
Alimentación Animal , Lactancia , Femenino , Bovinos , Animales , Lactancia/fisiología , Alimentación Animal/análisis , Leche , Dieta/veterinaria , Digestión , Suplementos Dietéticos/análisis , Rumen
20.
Ecotoxicol Environ Saf ; 264: 115416, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37647801

RESUMEN

Cadmium (Cd) is a common contaminant in aquatic environments. However, little is known about the mechanisms underlying Cd toxicity in the freshwater snail Cipangopaludina cathayensis (Heude, 1890). This study to investigate the toxic effects of Cd on the standard metabolism, antioxidant activities, immune function, and hepatopancreas transcriptome profiles of C. cathayensis. C. cathayensis was exposed to 0.25, 0.5, 1.0, or 1.5 mg/L Cd for 3 h, with results showing that Cd significantly inhibited oxygen consumption and ammonia excretion and disrupted the respiratory metabolism of C. cathayensis. In addition, the O:N ratio dropped below 7, indicating that C. cathayensis may rely exclusively on proteins as an energy source under Cd stress. To understand how Cd impacts the antioxidant activities, immune function, and transcriptional profiles, C. cathayensis were exposed to 0.5 (low exposure, L14) or 1.5 (high exposure, H14) mg/L Cd for 14 days. Our results indicate that Cd exposure leads to oxidative stress and immunosuppression, with the latter effect being larger for exposure to higher Cd concentrations. A total of 2172 differentially expressed genes (DEGs) were identified by transcriptome analysis of the hepatopancreas, of which 885 were upregulated and 1287 were downregulated. Gene ontology and KEGG analyses revealed that the DEGs in the H14 group are enriched for energy generation terms and the "oxidative phosphorylation" pathway, respectively. Therefore, up-regulation of energy metabolism may be an adaptive strategy under Cd stress. Moreover, several genes involved in antioxidant activity were downregulated, whereas genes related to reactive oxygen species generation were upregulated. In addition, many immunity-related genes were identified within the DEGs, indicating that Cd toxicity may affect immune defense. Further, DEGs in the H14 group were enriched for disease-associated pathways. Taken together, our results indicate that Cd exposure leads to metabolic disorders, oxidative stress, and immunosuppression and thus may potentially contribute to disease outbreaks.


Asunto(s)
Antioxidantes , Transcriptoma , Animales , Antioxidantes/metabolismo , Cadmio/metabolismo , Hepatopáncreas/metabolismo , Inmunidad
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