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1.
Bioorg Chem ; 145: 107181, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38354503

RESUMEN

The human CC chemokine receptor 8 (CCR8) has been extensively pursued as target for the treatment of various inflammatory disorders. More recently, the importance of CCR8 in the tumor microenvironment has been demonstrated, spurring the interest in CCR8 antagonism as therapeutic strategy in immuno-oncology. On a previously described naphthalene sulfonamide with CCR8 antagonistic properties, the concept of isosterism was applied, leading to the discovery of novel CCR8 antagonists with IC50 values in the nM range in both the CCL1 competition binding and CCR8 calcium mobilization assay. The excellent CCR8 antagonistic activity of the most potent congeners was rationalized by homology molecular modeling.


Asunto(s)
Quimiocinas CC , Receptores de Quimiocina , Humanos , Quimiocinas CC/metabolismo , Quimiocina CCL1/metabolismo , Receptores de Quimiocina/química , Receptores de Quimiocina/metabolismo , Amidas , Receptores CCR8 , Sulfonamidas/farmacología , Naftalenos/farmacología
2.
Protein Sci ; 32(4): e4599, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36806291

RESUMEN

We report the discovery of the androgen receptor missense mutation V770D, that was found in two sisters suffering from complete androgen insensitivity. Experimental validation of AR V770 variants demonstrated that AR V770D was transcriptionally inactive due to the inability to dimerize and a reduced ligand binding affinity. The more conservative AR V770A variant showed a dimerization defect at low levels of DHT with a partial recovery of the transcriptional activity and of the receptor's ability to dimerize when increasing the DHT levels. With V770 located outside of the proposed LBD dimerization interface of the AR LBD homodimer crystal structure, the effects of the V770A mutation on AR dimerization were unexpected. We therefore explored whether the AR LBD dimerization interface would be better described by an alternative dimerization mode based on available human homodimeric LBD crystal structures of other nuclear receptors. Superposition of the monomeric AR LBD in the homodimeric crystal structures of GR, PR, ER, CAR, TRß, and HNF-4α showed that the GR-like LBD dimer model was energetically the most stable. Moreover, V770 was a key energy residue in the GR-like LBD dimer while it was not involved in the stabilization of the AR LBD homodimer according to the crystal structure. Additionally, the observation that 4 AIS mutations impacted the stability of the AR LBD dimer while 16 mutations affected the GR-like LBD dimer, suggested that the AR LBD dimer crystal is a snapshot of a breathing AR LBD homodimer that can transition into the GR-like LBD dimer model.


Asunto(s)
Síndrome de Resistencia Androgénica , Receptores Androgénicos , Masculino , Humanos , Receptores Androgénicos/genética , Receptores Androgénicos/química , Síndrome de Resistencia Androgénica/genética , Ligandos , Unión Proteica/genética , Mutación Missense , Mutación
3.
Mol Cancer Ther ; 21(12): 1823-1834, 2022 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-36218067

RESUMEN

Currently, all clinically used androgen receptor (AR) antagonists target the AR ligand-binding pocket and inhibit T and dihydrotestosterone (DHT) binding. Resistance to these inhibitors in prostate cancer frequently involves AR-dependent mechanisms resulting in a retained AR dependence of the tumor. More effective or alternative AR inhibitors are therefore required to limit progression in these resistant stages. Here, we applied the structural information of the ligand-binding domain (LBD) dimerization interface to screen in silico for inhibitors. A completely new binding site, the Dimerisation Inhibiting Molecules (DIM) pocket, was identified at the LBD dimerization interface. Selection of compounds that fit the DIM pocket via virtual screening identified the DIM20 family of compounds which inhibit AR transactivation and dimerization of the full-length AR as well as the isolated LBDs. Via biolayer interferometry, reversible dose-dependent binding to the LBD was confirmed. While DIM20 does not compete with 3H-DHT for binding in the LBP, it limits the maximal activity of the AR indicative of a noncompetitive binding to the LBD. DIM20 and DIM20.39 specifically inhibit proliferation of AR-positive prostate cancer cell lines, with only marginal effects on AR-negative cell lines such as HEK 293 and PC3. Moreover, combination treatment of DIM compounds with enzalutamide results in synergistic antiproliferative effects which underline the specific mechanism of action of the DIM compounds.


Asunto(s)
Neoplasias de la Próstata , Receptores Androgénicos , Masculino , Humanos , Receptores Androgénicos/metabolismo , Ligandos , Dimerización , Células HEK293 , Antagonistas de Receptores Androgénicos/farmacología , Dihidrotestosterona/farmacología , Dihidrotestosterona/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Línea Celular Tumoral , Antagonistas de Andrógenos/farmacología
4.
Cureus ; 14(8): e27615, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36059365

RESUMEN

Psychosis is a constellation of symptoms that present with a disconnect from reality. The duration, severity, and presentation of symptoms can present on a wide spectrum, and etiologies can vary from patient to patient. Psychosis is also associated with self-injurious thinking, behavior, and suicidality. Long-term treatment of psychosis with antipsychotics can often result in side effects like constipation, sedation, dry mouth, and metabolic syndrome. Though rectal prolapse is uncommon in adolescent patients, there was a noted correlation with rectal prolapse in adult patients that were treated for chronic psychiatric disease. We report a case of a 17-year-old female with psychosis and rectal prolapse, who was admitted for inpatient treatment.

5.
Evol Appl ; 14(10): 2457-2469, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34745337

RESUMEN

Multiple stressors linked to anthropogenic activities can influence how organisms adapt and evolve. So far, a consensus on how multiple stressors drive adaptive trajectories in natural populations has not been reached. Some meta-analysis reports show predominance of additive effects of stressors on ecological endpoints (e.g., fecundity, mortality), whereas others show synergistic effects more frequently. Moreover, it is unclear what mechanisms of adaptation underpin responses to complex environments. Here, we use populations of Daphnia magna resurrected from different times in the past to investigate mechanisms of adaptation to multiple stressors and to understand how historical exposure to environmental stress shapes adaptive responses of modern populations. Using common garden experiments on resurrected modern and historical populations, we investigate (1) whether exposure to one stress results in higher tolerance to a second stressor; (2) the mechanisms of adaptation underpinning long-term evolution to multistress (genetic evolution, plasticity, evolution of plasticity); and (3) the interaction effects of multiple stressors on fitness (synergism, antagonism, additivity). We measure the combined impact of different levels of resource availability (algae) and biocides on fitness-linked life-history traits and interpret these results in light of historical environmental exposures. We show that exposure to one stressor can alter tolerance to second stressors and that the interaction effect depends on the severity of either stressor. We also show that mechanisms of adaptation underpinning phenotypic evolution significantly differ in single-stress and multistress scenarios. These adaptive responses are driven largely by synergistic effects on fecundity and size at maturity, and additive effects on age at maturity. Exposure to multiple stressors shifts the trade-offs among fitness-linked life-history traits, with a stronger effect on Daphnia populations when low-resource availability and high biocide levels are experienced. Our study indicates that mitigation interventions based on single-stress analysis may not capture realistic threats.

6.
PLoS One ; 16(8): e0256074, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34388178

RESUMEN

BACKGROUND: Asian-Americans are one of the most understudied racial/ethnic minority populations. To increase representation of Asian subgroups, researchers have traditionally relied on data collection at community venues and events. However, the COVID-19 pandemic has created serious challenges for in-person data collection. In this case study, we describe multi-modal strategies for online recruitment of U.S. Vietnamese parents, compare response rates and participant characteristics among strategies, and discuss lessons learned. METHODS: We recruited 408 participants from community-based organizations (CBOs) (n = 68), Facebook groups (n = 97), listservs (n = 4), personal network (n = 42), and snowball sampling (n = 197). Using chi-square tests and one-way analyses of variance, we compared participants recruited through different strategies regarding sociodemographic characteristics, acculturation-related characteristics, and mobile health usage. RESULTS: The overall response rate was 71.8% (range: 51.5% for Vietnamese CBOs to 86.6% for Facebook groups). Significant differences exist for all sociodemographic and almost all acculturation-related characteristics among recruitment strategies. Notably, CBO-recruited participants were the oldest, had lived in the U.S. for the longest duration, and had the lowest Vietnamese language ability. We found some similarities between Facebook-recruited participants and those referred by Facebook-recruited participants. Mobile health usage was high and did not vary based on recruitment strategies. Challenges included encountering fraudulent responses (e.g., non-Vietnamese). Perceived benefits and trust appeared to facilitate recruitment. CONCLUSIONS: Facebook and snowball sampling may be feasible strategies to recruit U.S. Vietnamese. Findings suggest the potential for mobile-based research implementation. Perceived benefits and trust could encourage participation and may be related to cultural ties. Attention should be paid to recruitment with CBOs and handling fraudulent responses.


Asunto(s)
Asiático/estadística & datos numéricos , Internet , Selección de Paciente , Adulto , Asiático/psicología , Características Culturales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sesgo de Selección , Factores Socioeconómicos
7.
Bioorg Chem ; 107: 104560, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33383325

RESUMEN

The naphthalene sulfonamide scaffold is known to possess CCR8 antagonistic properties. In order to expand the structure-activity relationship study of this compound class, a variety of palladium-catalyzed cross-coupling reactions was performed on a bromo-naphthalene precursor yielding a diverse library. These compounds displayed CCR8 antagonistic properties in binding and calcium mobilization assays, with IC50 values in the 0.2 - 10 µM range. The decreased activity, when compared to the original lead compound, was rationalized by homology molecular modeling.


Asunto(s)
Bromo/química , Naftalenos/química , Paladio/química , Receptores CCR8/antagonistas & inhibidores , Sitios de Unión , Catálisis , Humanos , Simulación del Acoplamiento Molecular , Naftalenos/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Receptores CCR8/metabolismo , Relación Estructura-Actividad
8.
BMC Zool ; 6(1): 7, 2021 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37170320

RESUMEN

BACKGROUND: The key to fishery management is knowing the appropriate reproductive strategies of the targeted fish. For most gobiid species, the iteroparous pattern is dominant compared to semelparity. Albeit Butis koilomatodon plays an important role in the Mekong Delta's food supply, its reproductive biological data have not been known. Hence, this study was conducted to provide new fundamental knowledge of reproductive traits of Butis koilomatodon in the Mekong Delta. RESULTS: A total of 1314 individuals (903 males and 411 females) were monthly collected by bottom gill nets from July 2019 to June 2020 at six sampling sites along estuarial and coastal regions, from Tra Vinh to Ca Mau provinces, southern of Vietnam. pH and salinity of these six sampling sites are 7.72-7.93 pH and 11.17-26.17‰, respectively. The pH varies with sites, but not seasons; whereas a reverse case is found in salinity. Different types of oocytes are found in histological specimens of ovaries prove that B. koilomatodon is a multi-spawner. The gonadosomatic index value, together with the monthly presence of mature ovaries reveal that this species spawns throughout the year. The length at first mature male Butis koilomatodon (5.1-8.6 cm) is higher than that of females (4.8-6.7 cm), except in Hoa Binh and Dong Hai. Batch fecundity (3085 to 32,087 eggs/female) increases with fish weight (1.48-12.30 g) and length (4.8-9.0 cm) due to high determination values (r2 > 0.6). CONCLUSION: Knowledge of reproductive traits gained from this study was a reference source for future studies and helped manage this species' resources.

9.
Vaccine ; 38(41): 6388-6401, 2020 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-32829979

RESUMEN

INTRODUCTION: Asian-Americans have been documented to have low human papillomavirus (HPV) vaccine initiation and completion. No research has attempted to examine underlying mechanisms of HPV vaccine uptake disparities among Asian-Americans. Using the P3 (practice, provider, and patient) model, this study aimed to identify practice-, provider-, and patient-level determinants of Asian-Americans' HPV vaccine intention and uptake. METHODS: We conducted a systematic review of published literature regarding practice-, provider- and patient-level determinants of vaccine intention (e.g., intention, willingness, or acceptability) and uptake (e.g., initiation or completion). Eligible studies were those presenting empirical/original data, focusing on Asian populations in the U.S., including outcomes related to HPV vaccine intention and uptake, and analyzing data on factors associated with these outcomes separately for Asian groups. RESULTS: Twenty-six studies (19 quantitative and 7 qualitative studies) were included in the review. Most commonly studied subgroups were Koreans (n = 9), Chinese (n = 6), and Cambodians (n = 5). Studies showed varied prevalence across subgroups (intention: 23.4%-72%; initiation: 14%-67%; completion: 9%-63%). Only 3 studies included measurements of practice-level determinants (language services, insurance policy). Twelve studies measured provider-level determinants (most commonly documented: HPV vaccine recommendation). All studies measured patient-level determinants (most commonly documented: HPV and HPV vaccine knowledge, perceived safety, perceived susceptibility, and perceived relationship between HPV vaccine and sexual activity). CONCLUSIONS: Existing research on determinants of HPV vaccine intention and uptake among Asian-Americans currently lacks measurements of practice-level constructs and perspectives of clinic staff and providers, which are needed to guide system-level interventions and provider training. Data regarding patient-level determinants suggest that interventions for Asian-American populations can focus on providing educational information in culturally-appropriate manners, leveraging familial influences, and attending to access-related or cultural beliefs about HPV vaccine. Interventions should take into account varied vaccine intention and uptake prevalence in different Asian subgroups.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Instituciones de Atención Ambulatoria , Conocimientos, Actitudes y Práctica en Salud , Humanos , Intención , Infecciones por Papillomavirus/prevención & control , Aceptación de la Atención de Salud , Vacunación
10.
Perit Dial Int ; 40(2): 171-178, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32063195

RESUMEN

BACKGROUND: For the treatment of peritoneal dialysis-associated peritonitis (PDAP), ceftazidime is routinely admixed with peritoneal dialysis (PD) solutions before its intraperitoneal administration. One of the major degradation products of ceftazidime is pyridine, a potentially toxic compound. Depending on the type of PD solution, ceftazidime is exposed to an environment with acidic or basic pH, and depending on the type of dosing and individual unit practices related to preparation and storage, ceftazidime can be at body temperature for 4-10 h, resulting in potentially varying rates of degradation to pyridine by-product. No study has investigated whether the amount of generated pyridine exceeds the maximum daily exposure limit of 2 mg when ceftazidime-PD admixtures are kept at body temperature. Therefore, the current study aimed to determine the levels of pyridine generated in PD-ceftazidime admixtures kept at 37°C for various time points. METHODS: Ceftazidime was admixed with 2 L Dianeal (1.5%, 2.5% and 4.25% dextrose) and 2 L Physioneal (1.36%, 2.27% and 3.86% glucose) PD solutions to obtain a concentration of 125 mg/L (continuous dosing model) or 500 mg/L (intermittent dosing model). A total of 36 PD admixtures (3 bags for each type of PD solution and 3 bags for each type of dosing) were prepared and stored at 37°C for 10 h. An aliquot was withdrawn at time 0 (baseline) and after 2, 6, 8 and 10 h of storage. The withdrawn samples were then analysed to determine the concentrations of ceftazidime and pyridine using high-performance liquid chromatography. RESULTS: With the intermittent dosing model (500 mg/L), ceftazidime was found to be stable for only 2 and 6 h when admixed with 3.86% and 2.27% glucose Physioneal PD solutions, respectively. While ceftazidime (500 mg/L) retained more than 90% of its initial concentration in the three types of Dianeal and 1.36% dextrose Physioneal solutions for 10 and 8 h, respectively, the generated amount of pyridine ranged between approximately 290% and 371% more than the daily recommended limit. With the continuous dosing model (125 mg/L), ceftazidime was found to be stable for 6 h in all three types of Physioneal PD solutions, but the total amount of generated pyridine with four daily exchanges (6 h each) was estimated to be 170-360% over the daily recommended limit. Ceftazidime (125 mg/L) was chemically stable when admixed with three types of Dianeal PD solutions and stored at 37°C for 10 h, and the levels of pyridine were estimated to be less than the maximum recommended daily limit. CONCLUSIONS: Until the outcomes of this in vitro study are confirmed by appropriate in vivo studies, continuous dosing of ceftzadime-Dianeal admixtures for the treatment of PDAP may be preferred over continuous dosing of ceftazidime-Physioneal admixtures, and intermittent dosing of ceftazidime-Physioneal and ceftazidime-Dianeal admixtures, as ceftazidime remains stable and the generated levels of pyridine are below the maximum recommended daily exposure.


Asunto(s)
Antibacterianos/química , Ceftazidima/química , Soluciones para Diálisis/química , Diálisis Peritoneal , Piridinas/análisis , Temperatura , Temperatura Corporal , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Humanos , Peritonitis/prevención & control
12.
Pediatr Transplant ; 19(5): 510-6, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25907302

RESUMEN

Multiple duct anastomoses during LLS transplantation increase the incidence of biliary complications. The optimal plane of hepatotomy that results in the least number of bile ducts at the surface was investigated according to LHD variations. Ducts of 30 human livers were injected with resin and LHD branching on 3D-CT reconstructions were analyzed. Ducts on the virtual hepatotomy surface were estimated in three splitting lines. Variations with subtypes were described. Ia (66.7%): ducts from segments (S.) II-III form a common trunk and S.IV duct joins it. Ib (10%): common trunk formed by ducts from S.II-S.III while S.IV duct joins the common hepatic duct. IIa (16.67%): S.IV duct drains into S.III duct. IIc (3.33%): S.IV duct drains into both S.II and S.III ducts. III (3.33%): trifurcation of S.II, S.III and S.IV ducts. When the virtual hepatotomy line was on the FL, there was a single duct for the anastomosis in 30% of cases but two, three, or four ducts in 53.3%, 10%, and 3.3%, respectively. Division 1 cm to the right of the FL resulted in one duct (70%), but S.IV duct injury may occur. LLS hepatotomy should not necessarily be performed along the FL. Variations must be taken into consideration to minimize the number of biliary anastomoses during liver implantation.


Asunto(s)
Conductos Biliares/cirugía , Hepatectomía/métodos , Conducto Hepático Común/cirugía , Hígado/anatomía & histología , Donadores Vivos , Adulto , Anastomosis Quirúrgica , Autopsia , Conductos Biliares/anatomía & histología , Procedimientos Quirúrgicos del Sistema Biliar , Colangiografía/métodos , Conducto Hepático Común/anatomía & histología , Humanos , Imagenología Tridimensional , Hígado/cirugía , Trasplante de Hígado , Páncreas/anatomía & histología , Tomografía Computarizada por Rayos X
13.
J Pharm Pharmacol ; 60(2): 171-8, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18237464

RESUMEN

The plasma pharmacokinetics and brain uptake of the novel neuroprotective agent AM-36 (1-(2-(4-chlorophenyl)-2-hydroxy)ethyl-4-(3,5-bis-(1,1dimethylethyl)-4-hydroxyphenyl) methylpiperazine) were assessed over 72 h following i.v. administration to male Sprague-Dawley rats. At nominal i.v. doses of 0.2, 1 and 3mg kg(-1), AM-36 exhibited an extremely large volume of distribution (18.2-24.6 L kg(-1)) and a long terminal elimination half-life, ranging from 25.2 to 37.7 h. Over this dose range, AM-36 exhibited linear pharmacokinetics, with no apparent change in clearance, volume of distribution or dose-normalised area under the plasma concentration - time curve. AM-36 was very highly bound to plasma proteins (> 99.6%); however, this did not appear to affect the ability of AM-36 to permeate the blood-brain barrier. Following a single i.v. dose of AM-36 at 3mg kg(-1) to rats, brain concentrations were detected for up to 72 h, and the brain-to-plasma ratios were high at all time points (ranging from 8.2 at 5 min post-dose to 0.9 at 72 h post-dose). The very high brain uptake of AM-36 supports previous in-vivo efficacy studies demonstrating the neuroprotective effects of this compound when administered to rats with middle cerebral artery occlusion.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Fármacos Neuroprotectores/farmacocinética , Piperazinas/farmacocinética , Animales , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Semivida , Inyecciones Intravenosas , Masculino , Fármacos Neuroprotectores/administración & dosificación , Piperazinas/administración & dosificación , Unión Proteica , Ratas , Ratas Sprague-Dawley , Factores de Tiempo , Distribución Tisular
14.
Tohoku J Exp Med ; 210(1): 21-7, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16960341

RESUMEN

An off-season community influenza outbreak with high prevalence of amantadine-resistant influenza A/H3N2 occurred during September-October 2005 in Nagasaki Prefecture, Japan, prior to standard influenza circulation. A total of 48 patients with influenza-like-illness (ILI) visited a clinic during the outbreak and 27 (69.2%) of 39 ILI patients were positive for influenza A with rapid antigen testing (Quick Vue Rapid SP Influ). Nine patients were not tested because their symptoms were compatible for influenza without examination. Nasopharyngeal swabs were obtained from 4 of 27 rapid test positive patients, and influenza H3N2 strain was isolated from one out of four. The 4 nasopharyngeal samples were positive for influenza A M2 gene in polymerase chain reaction, and sequencing results all showed identical mutation at position 31, serine to asparagine (S31N) in the gene, conferring amantadine resistance. The phylogenetic tree analysis demonstrated that the hemagglutinin (HA) gene sequences of the 4 samples formed a distinct cluster (named clade N) from recent circulating H3N2 strains, characterized by dual mutations at position 193, serine to phenylalanine (S193F), and at position 225, asparatic acid to asparagine (D225N). Our findings suggested that an off-season community influenza outbreak in Nagasaki was caused by a distinct clade in H3N2 (named clade N), which possessed characteristics of amantadine resistance.


Asunto(s)
Brotes de Enfermedades/prevención & control , Subtipo H3N2 del Virus de la Influenza A/genética , Gripe Humana/epidemiología , Estaciones del Año , Acetamidas/farmacología , Acetamidas/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Amantadina/farmacología , Amantadina/uso terapéutico , Sustitución de Aminoácidos , Antivirales/farmacología , Antivirales/uso terapéutico , Niño , Preescolar , Farmacorresistencia Viral/genética , Femenino , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Humanos , Lactante , Subtipo H3N2 del Virus de la Influenza A/efectos de los fármacos , Subtipo H3N2 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/tratamiento farmacológico , Japón/epidemiología , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Oseltamivir , Filogenia , Resultado del Tratamiento , Proteínas de la Matriz Viral/genética
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