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1.
Proc Natl Acad Sci U S A ; 119(43): e2211431119, 2022 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-36264833

RESUMEN

Actomyosin contractile force produced by myosin II molecules that bind and pull actin filaments is harnessed for diverse functions, from cell division by the cytokinetic contractile ring to morphogenesis driven by supracellular actomyosin networks during development. However, actomyosin contractility is intrinsically unstable to self-reinforcing spatial variations that may destroy the actomyosin architecture if unopposed. How cells control this threat is not established, and while large myosin fluctuations and punctateness are widely reported, the full course of the instability in cells has not been observed. Here, we observed the instability run its full course in isolated cytokinetic contractile rings in cell ghosts where component turnover processes are absent. Unprotected by turnover, myosin II merged hierarchically into aggregates with increasing amounts of myosin and increasing separation, up to a maximum separation. Molecularly explicit simulations reproduced the hierarchical aggregation which precipitated tension loss and ring fracture and identified the maximum separation as the length of actin filaments mediating mechanical communication between aggregates. In the final simulated dead-end state, aggregates were morphologically quiescent, including asters with polarity-sorted actin, similar to the dead-end state observed in actomyosin systems in vitro. Our results suggest the myosin II turnover time controls actomyosin contractile instability in normal cells, long enough for aggregation to build robust aggregates but sufficiently short to intercept catastrophic hierarchical aggregation and fracture.


Asunto(s)
Actinas , Actomiosina , Actomiosina/metabolismo , Actinas/metabolismo , Citoesqueleto de Actina/metabolismo , Miosinas/metabolismo , Miosina Tipo II/metabolismo , Citocinesis/fisiología , Proteínas del Citoesqueleto/metabolismo
2.
Genes Dev ; 29(11): 1175-87, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-26063575

RESUMEN

Topoisomerase IV (topo IV), an essential factor during chromosome segregation, resolves the catenated chromosomes at the end of each replication cycle. How the decatenating activity of the topo IV is regulated during the early stages of the chromosome cycle despite being in continuous association with the chromosome remains poorly understood. Here we report a novel cell cycle-regulated protein in Caulobacter crescentus, NstA (negative switch for topo IV decatenation activity), that inhibits the decatenation activity of the topo IV during early stages of the cell cycle. We demonstrate that in C. crescentus, NstA acts by binding to the ParC DNA-binding subunit of topo IV. Most importantly, we uncover a dynamic oscillation of the intracellular redox state during the cell cycle, which correlates with and controls NstA activity. Thus, we propose that predetermined dynamic intracellular redox fluctuations may act as a global regulatory switch to control cellular development and cell cycle progression and may help retain pathogens in a suitable cell cycle state when encountering redox stress from the host immune response.


Asunto(s)
Proteínas Bacterianas/metabolismo , Caulobacter crescentus/enzimología , Ciclo Celular/fisiología , Topoisomerasa de ADN IV/metabolismo , Genes de Cambio/fisiología , Caulobacter crescentus/crecimiento & desarrollo , Topoisomerasa de ADN IV/genética , Activación Enzimática/fisiología , Oxidación-Reducción , Unión Proteica , Subunidades de Proteína/metabolismo
3.
Cell Mol Life Sci ; 78(24): 8049-8071, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34748024

RESUMEN

Multiple RNA pathways are required to produce functional sperm. Here, we review RNA post-transcriptional regulation during spermatogenesis with particular emphasis on the role of 3' end modifications. From early studies in the 1970s, it became clear that spermiogenesis transcripts could be stored for days only to be translated at advanced stages of spermatid differentiation. The transition between the translationally repressed and active states was observed to correlate with the shortening of the transcripts' poly(A) tail, establishing a link between RNA 3' end metabolism and male germ cell differentiation. Since then, numerous RNA metabolic pathways have been implicated not only in the progression through spermatogenesis, but also in the maintenance of genomic integrity. Recent studies have characterized the elusive 3' biogenesis of Piwi-interacting RNAs (piRNAs), identified a critical role for messenger RNA (mRNA) 3' uridylation in meiotic progression, established the mechanisms that destabilize transcripts with long 3' untranslated regions (3'UTRs) in post-mitotic cells, and defined the physiological relevance of RNA exonucleases and deadenylases in male germ cells. In this review, we discuss RNA processing in the male germline in the light of the most recent findings. A brief recollection of different RNA-processing events will aid future studies exploring post-transcriptional regulation in spermatogenesis.


Asunto(s)
Regulación de la Expresión Génica , Procesamiento Postranscripcional del ARN , Espermatogénesis , Espermatozoides/fisiología , Animales , Humanos , Masculino , Espermatozoides/citología
4.
J Dairy Sci ; 105(1): 56-71, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34756432

RESUMEN

We investigated the effects of different concentrations of whey protein isolate (WPI) on oat starch characteristics in terms of pasting, thermal, and structural properties. The pasting properties of the starch showed that hot paste viscosity increased with the addition of WPI in the system, and relative breakdown decreased. Thermal analysis showed a significant effect of WPI on oat starch by increasing the peak temperature of differential scanning calorimeter endotherms. The X-ray diffraction and Fourier transform infrared spectroscopy studies revealed that WPI increased the ordered structuration of starch paste, as evident by an increase in relative crystallinity; in addition, a decrease in infrared bands at 1,024 cm-1 and 1,080 cm-1 suggested decreased gelatinization of oat starch granules. Overall, WPI at different concentrations affected the oat starch gelatinization properties.


Asunto(s)
Avena , Almidón , Animales , Viscosidad , Proteína de Suero de Leche , Difracción de Rayos X/veterinaria
5.
AAPS PharmSciTech ; 22(7): 221, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34409506

RESUMEN

This work describes lyophilization process validation and consists of two parts. Part I focuses on the process design and is described in the current paper, while part II is devoted to process qualification and continued process verification. The intent of these articles is to provide readers with recent updates on lyophilization validation in the light of community-based combined opinion on the process and reflect the industrial prospective. In this paper, the design space approach for process design is described in details, and examples from practice are provided. The approach shows the relationship between the process inputs; it is based on first principles and gives a thorough scientific understanding of process and product. The lyophilization process modeling and scale-up are also presented showing the impact of facility, equipment, and vial heat transfer coefficient. The case studies demonstrating the effect of batch sizes, fill volume, and dose strength to show the importance of modeling as well as the effect of controlled nucleation on product resistance are discussed.


Asunto(s)
Calor , Tecnología Farmacéutica , Liofilización , Estudios Prospectivos , Temperatura
6.
Mol Pharm ; 16(11): 4485-4495, 2019 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-31568722

RESUMEN

Solid-state hydrogen-deuterium exchange with mass spectrometry (ssHDX-MS) was evaluated as an analytical method to rapidly screen and select an optimal lyophilized fragment antigen binding protein (Fab) formulation and the optimal lyophilization cycle. ssHDX-MS in lyophilized Fab formulations, varying in stabilizer type and stabilizer/protein ratio, was conducted under controlled humidity and temperature. The extent of deuterium incorporation was measured using mass spectrometry and correlated with solid-state stress degradation at 50 °C as measured by size exclusion chromatography (SEC) and ion-exchange chromatography (IEC). ssHDX-MS was also used to evaluate the impact of three different types of lyophilization processing on storage stability: controlled ice nucleation (CN), uncontrolled ice nucleation (UCN), and annealing (AN). The extent of deuterium incorporation for different Fab formulations agreed with the order of solid-state stress degradation, with formulations having lower deuterium incorporation showing lower stress-induced degradation (aggregation and charge modifications). For lyophilization processing, no significant effect of ice nucleation was observed in either solid-state stress degradation or in the extent of deuterium incorporation for high concentration Fab formulations (25 mg/mL). In contrast, for low concentration Fab formulations (2.5 mg/mL), solid-state stability from different lyophilization processes correlated with the extent of deuterium incorporation. The order of solid-state degradation (AN < CN < UCN) was the same as the extent of deuterium incorporation on ssHDX-MS (AN < CN < UCN). The extent of deuterium incorporation on ssHDX-MS correlated well with the solid-state stress degradation for different Fab formulations and lyophilization processing methods. Thus, ssHDX-MS can be used to rapidly screen and optimize the formulation and lyophilization process for a lyophilized Fab, reducing the need for time-consuming stress degradation studies.


Asunto(s)
Deuterio/química , Hidrógeno/química , Fragmentos Fab de Inmunoglobulinas/química , Química Farmacéutica/métodos , Cromatografía Líquida de Alta Presión/métodos , Cromatografía por Intercambio Iónico/métodos , Medición de Intercambio de Deuterio/métodos , Liofilización/métodos , Espectrometría de Masas de Intercambio de Hidrógeno-Deuterio/métodos , Cinética , Unión Proteica
7.
Reprod Biol Endocrinol ; 16(1): 56, 2018 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-29859541

RESUMEN

BACKGROUND: Spermatogenesis in most mammals (including human and rat) occurs at ~ 3 °C lower than body temperature in a scrotum and fails rapidly at 37 °C inside the abdomen. The present study investigates the heat-sensitive transcriptome and miRNAs in the most vulnerable germ cells (spermatocytes and round spermatids) that are primarily targeted at elevated temperature in a bid to identify novel targets for contraception and/or infertility treatment. METHODS: Testes of adult male rats subjected to surgical cryptorchidism were obtained at 0, 24, 72 and 120 h post-surgery, followed by isolation of primary spermatocytes and round spermatids and purification to > 90% purity using a combination of trypsin digestion, centrifugal elutriation and density gradient centrifugation techniques. RNA isolated from these cells was sequenced by massive parallel sequencing technique to identify the most-heat sensitive mRNAs and miRNAs. RESULTS: Heat stress altered the expression of a large number of genes by ≥2.0 fold, out of which 594 genes (286↑; 308↓) showed alterations in spermatocytes and 154 genes (105↑; 49↓) showed alterations in spermatids throughout the duration of experiment. 62 heat-sensitive genes were common to both cell types. Similarly, 66 and 60 heat-sensitive miRNAs in spermatocytes and spermatids, respectively, were affected by ≥1.5 fold, out of which 6 were common to both the cell types. CONCLUSION: The study has identified Acly, selV, SLC16A7(MCT-2), Txnrd1 and Prkar2B as potential heat sensitive targets in germ cells, which may be tightly regulated by heat sensitive miRNAs rno-miR-22-3P, rno-miR-22-5P, rno-miR-129-5P, rno-miR-3560, rno-miR-3560 and rno-miR-466c-5P.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Calor , Espermatocitos/fisiología , Espermatogénesis/fisiología , Animales , Expresión Génica , Masculino , Ratas , Ratas Sprague-Dawley
8.
Mol Pharm ; 15(1): 1-11, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29182876

RESUMEN

Solid state hydrogen-deuterium exchange with mass spectrometric analysis (ssHDX-MS) has been used to assess protein conformation and matrix interactions in lyophilized solids. ssHDX-MS metrics have been previously correlated to the formation of aggregates of lyophilized myoglobin on storage. Here, ssHDX-MS was applied to lyophilized monoclonal antibody (mAb) formulations and correlated to their long-term stability. After exposing lyophilized samples to D2O(g), the amount of deuterium incorporated at various time points was determined by mass spectrometry for four different lyophilized mAb formulations. Hydrogen-deuterium exchange data were then correlated with mAb aggregation and chemical degradation, which was obtained in stability studies of >2.5 years. Deuterium uptake on ssHDX-MS of four lyophilized mAb formulations determined at the initial time point prior to storage in the dry state was directly and strongly correlated with the extent of aggregation and chemical degradation during storage. Other measures of physical and chemical properties of the solids were weakly or poorly correlated with stability. The data demonstrate, for the first time, that ssHDX-MS results are highly correlated with the stability of lyophilized mAb formulations. The findings thus suggest that ssHDX-MS can be used as an early read-out of differences in long-term stability between formulations helping to accelerate formulation screening and selection.


Asunto(s)
Anticuerpos Monoclonales/química , Medición de Intercambio de Deuterio/métodos , Liofilización/métodos , Espectrometría de Masas/métodos , Cromatografía Líquida de Alta Presión , Cromatografía por Intercambio Iónico , Cromatografía Liquida , Composición de Medicamentos , Microscopía Electrónica de Rastreo
9.
Inorg Chem ; 56(16): 9535-9546, 2017 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-28782943

RESUMEN

A series of structurally characterized magnesium and zinc complexes of the form L4-tBuPh-M{N(SiMe3)2}2 [M = Mg (1) and Zn (2); L4-tBuPh = 1,3-diethyl-4,5-dimethylimidazolium-2-{N,N'-bis(4-tert-butylphenyl)amidinate}], L4-iPrPh-M{N(SiMe3)2}2 [M = Mg (3) and Zn (4); L4-iPrPh = 1,3-diethyl-4,5-dimethylimidazolium-2-{N,N'-bis(4-isopropylphenyl)amidinate}], and L4-iPrPh-ZnEt2 (5) bearing a zwitterionic-type neutral amidinate or N-heterocyclic carbene-carbodiimide ("NHC-CDI") adduct and monoanionic amido or alkyl ligands have been reported. The synthesis of compounds 1-5 was achieved by the direct addition of a "NHC-CDI" adduct to a corresponding metal bis(amide) or dialkyl reagent. All compounds 1-5 exist as monomers in the solid state. In all cases, the metal (magnesium or zinc) centers adopt a distorted four-coordinate tetrahedral geometry bonded to one N,N'-chelated neutral zwitterionic ligand and two monoanionic amido or alkyl moieties. In contrast, sterically bulky zwitterionic amidinate 1,3-diethyl-4,5-dimethylimidazolium-2-{N,N'-bis(2,6-diisopropylphenyl)amidinate} (LDipp) upon treatment with lithium bis[(trimethylsilyl)amide], Li{N(SiMe3)2}, affords the NHC-lithium complex MeIEt-[Li{N(SiMe3)2}]2 (6), in which one molecule of NHC (MeIEt = 1,3-diethyl-4,5-dimethylimidazol-2-ylidene) coordinates to one of the two lithium centers. In a similar way, the reaction between LDipp and Mg{N(SiMe3)2}2 allowed the formation of a NHC adduct of metal bis(amide), MeIEt-Mg{N(SiMe3)2}2 (7), instead of a zwitterionic adduct of metal bis(amide). Alternatively, the synthesis of both compounds 6 and 7 was achieved by the direct addition of 1 equiv of NHC, i.e., MeIEt to Li{N(SiMe3)2} (2.0 equiv) and Mg{N(SiMe3)2}2 (1.0 equiv) in benzene-d6, respectively. All compounds (1-7) were characterized by multinuclear {1H, 13C, and 29Si (for 1-4, 6, and 7) and 7Li (for compound 6)} magnetic resonance spectroscopy, mass spectrometry, elemental analysis, and single-crystal X-ray structural analysis. In addition, preliminary reactivity studies of zwitterion-supported metal complexes have been investigated. Furthermore, density functional theory calculations have been carried out to obtain the energetics of zwitterion-supported lithium and magnesium complexes.

10.
Biol Reprod ; 94(4): 96, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26984998

RESUMEN

Quiescent sperm survive in cauda epididymis for long periods of time under extreme crowding conditions and with a very limited energy substrate, while after ejaculation, motile sperm live for a much shorter period with an unlimited energy resource and without crowding. Thus, the energy metabolism in relation to the energy requirement of the two may be quite different. A simple physiological technique was evolved to collect viable quiescent sperm from rat cauda epididymis to compare its energy metabolism with motile sperm. Quiescent sperm exhibited 40%-60% higher activities of mitochondrial electron transport chain complexes I-IV and ATP synthase in comparison to motile sperm and accumulated Ca(2+) in the midpiece mitochondria to enhance oxidative phosphorylation (OxPhos). In contrast, motile sperm displayed up to 75% higher activities of key glycolytic enzymes and secreted more than two times the lactate than quiescent sperm. Quiescent sperm phosphorylated AMPK and MAPK-p38, while motile sperm phosphorylated AKT and MAPK/ERK. Glycolytic inhibitor iodoacetamide prevented motility activation of quiescent rat sperm and inhibited conception in rabbits more effectively than OxPhos uncoupler 2,4-dinitrophenol. Apparently, quiescent sperm employ the most energy efficient OxPhos to survive for extended periods of time under extreme conditions of nutrition and crowding. However, on motility initiation, sperm switch predominantly to glycolysis to cater to their high- and quick-energy requirement of much shorter periods. This study also presents a proof of concept for targeting sperm energy metabolism for contraception.


Asunto(s)
Metabolismo Energético , Motilidad Espermática , Animales , Calcio/metabolismo , Femenino , Fertilidad , Glucólisis , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Ácido Láctico/metabolismo , Sistema de Señalización de MAP Quinasas , Masculino , Mitocondrias/metabolismo , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Conejos , Ratas Sprague-Dawley
11.
Nature ; 464(7287): 367-73, 2010 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-20237561

RESUMEN

Fusarium species are among the most important phytopathogenic and toxigenic fungi. To understand the molecular underpinnings of pathogenicity in the genus Fusarium, we compared the genomes of three phenotypically diverse species: Fusarium graminearum, Fusarium verticillioides and Fusarium oxysporum f. sp. lycopersici. Our analysis revealed lineage-specific (LS) genomic regions in F. oxysporum that include four entire chromosomes and account for more than one-quarter of the genome. LS regions are rich in transposons and genes with distinct evolutionary profiles but related to pathogenicity, indicative of horizontal acquisition. Experimentally, we demonstrate the transfer of two LS chromosomes between strains of F. oxysporum, converting a non-pathogenic strain into a pathogen. Transfer of LS chromosomes between otherwise genetically isolated strains explains the polyphyletic origin of host specificity and the emergence of new pathogenic lineages in F. oxysporum. These findings put the evolution of fungal pathogenicity into a new perspective.


Asunto(s)
Cromosomas Fúngicos/genética , Fusarium/genética , Fusarium/patogenicidad , Genoma Fúngico/genética , Genómica , Evolución Molecular , Fusarium/clasificación , Interacciones Huésped-Parásitos/genética , Familia de Multigenes/genética , Fenotipo , Filogenia , Proteoma/genética , Análisis de Secuencia de ADN , Sintenía/genética , Virulencia/genética
13.
Hum Reprod ; 29(2): 242-52, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24291662

RESUMEN

STUDY QUESTION: Can a specifically acting synthetic spermicide (DSE-37) be combined with a natural microbicide (saponins) for safe, prophylactic contraception? SUMMARY ANSWER: A 1:1 (w/w) combination of DSE-37 and Sapindus saponins can target sperm and Trichomonas vaginalis precisely without any noticeable off-target effects on somatic cells at effective concentrations. WHAT IS KNOWN ALREADY: Broad-spectrum vaginal agents like nonoxynol-9 (N-9) and cellulose sulfate have failed clinically as microbicides due to non-specific off-target effects, whereas agents that specifically target retroviruses have shown promise in clinical trials. DSE-37 and Sapindus saponins, respectively, specifically target human sperm and T. vaginalis in vitro. STUDY DESIGN, SIZE, DURATION: A comprehensive study of efficacy and safety was undertaken using in vitro (human cells) and in vivo (rabbit) models. The 1:1 combination of DSE-37 and Sapindus saponins was based on the in vitro spermicidal and anti-Trichomonal activities of the two components. N-9, the spermicide in clinical use, served as reference control. Free sperm thiols were fluorescently glinted to reveal differences in the targets of the test agents. PARTICIPANTS/MATERIALS, SETTING, METHODS: On/off-target effects were evaluated in vitro against human sperm, T. vaginalis, HeLa, Vk2/E6E7, End1/E6E7 and Lactobacillus jensenii, using standard assays of drug susceptibility, cell viability, flow cytometric assessment of cell apoptosis and qPCR for expression of pro-inflammatory cytokine mRNAs. The spermicidal effect was also recorded live and free thiols on sperm were fluorescently visualized using a commercial kit. In vivo contraceptive efficacy (pregnancy/fertility rates) and safety (vaginal histopathology and in situ immune-labeling of inflammation markers VCAM-1, E-selectin and NFkB) were evaluated in rabbits. MAIN RESULTS AND THE ROLE OF CHANCE: A 0.003% drug 'combination' containing 0.0015% each of DSE-37 and Sapindus saponins in physiological saline irreversibly immobilized 100% human sperm in ∼30 s and eliminated 100% T. vaginalis in 24 h, without causing any detectable toxicity to human cervical (HeLa) cells and Lactobacilli in 24-48 h, in vitro. N-9 at 0.003% exhibited lower microbicidal activity against Trichomonas but failed in spermicidal assays while causing severe toxicity to HeLa cells and Lactobacilli in 12-24 h. The 'combination' of DSE-37 and Sapindus saponins completely prevented pregnancy in rabbits at a vaginal dose of 20 mg (1% in K-Y Jelly), while application of 5% 'combination' in K-Y Jelly for 4 consecutive days caused negligible alterations in epithelial lining of rabbit vagina with only minor changes in levels of inflammation markers. N-9 at a 20 mg vaginal dose prevented pregnancy in 33% animals and a 4-day repeat application of 2% N-9 gel caused severe local toxicity to vaginal epithelium with molecular expression of acute inflammation markers. LIMITATIONS, REASONS FOR CAUTION: The number of animals used for the in vivo efficacy study was limited by the approval of the animal ethics committee. WIDER IMPLICATIONS OF THE FINDINGS: Anti-Trichomonal contraceptives with specifically acting synthetic component and clinically-proven safe natural component may define a new concept in empowering women to control their fertility and reproductive health. STUDY FUNDING/COMPETING INTEREST(S): The study was funded by CSIR-Network Project 'PROGRAM' (BSC0101) and partly by the Ministry of Health and Family Welfare, Government of India (GAP0001). The funding agencies did not play any role in this study and none of the authors had any competing interest(s).


Asunto(s)
Aminoquinolinas/química , Antiinfecciosos/administración & dosificación , Anticonceptivos/uso terapéutico , Espermicidas/administración & dosificación , Animales , Disulfuros/química , Femenino , Células HeLa , Humanos , Inflamación , L-Lactato Deshidrogenasa/metabolismo , Masculino , Potencial de la Membrana Mitocondrial , Faloidina/química , Conejos , Sapindus/metabolismo , Semen/efectos de los fármacos , Espermatozoides/patología , Tensión Superficial , Tensoactivos/química , Trichomonas vaginalis/metabolismo
14.
Bioorg Med Chem Lett ; 24(16): 3903-6, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-25027939

RESUMEN

A series of γ-butyrolactone derivatives has been designed and synthesized from commercially available 2-acetyl butyrolactone (3-acetyldihydrofuran-2(3H)-one, 1) by aminoalkylating its active methylene followed by condensation with different aldehydes. Compounds having amino group were further converted to their respective tartrate salts and were evaluated for spermicidal activity against human sperm in vitro. Compounds showing appreciable spermicidal activity at ⩽0.5% [3c, 4d (0.5%); 2c, 3d (0.1%); 2d, 4c (0.05%)] were tested for safety studies against human cervical (HeLa) cell line. These compounds were found safer than, Nonoxynol-9. One of the two most active compounds was also found to be the safest (IC50=961 µg/ml; 4c), while the second compound exhibited lower safety against HeLa (IC50=269 µg/ml; 2d). The compound 4c significantly reduced the number of free thiols on human sperm. All the compounds were inactive against Trichomonas vaginalis.


Asunto(s)
4-Butirolactona/farmacología , Diseño de Fármacos , Espermicidas/farmacología , Espermatozoides/efectos de los fármacos , 4-Butirolactona/síntesis química , 4-Butirolactona/química , Relación Dosis-Respuesta a Droga , Células HeLa , Humanos , Masculino , Estructura Molecular , Espermicidas/síntesis química , Espermicidas/química , Espermatozoides/química , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/antagonistas & inhibidores , Trichomonas vaginalis/efectos de los fármacos
15.
Org Biomol Chem ; 12(19): 3090-9, 2014 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-24705515

RESUMEN

1-Substituted piperazinecarbodithioates were obtained by an unusual removal of CS2 in benzyl substituted dithiocarbamate derivatives under acid and basic conditions during design and synthesis of 1,4-(disubstituted)piperazinedicarbodithioates as double edged spermicides. A plausible mechanism for CS2 removal has been proposed. All synthesized compounds were subjected to spermicidal, antitrichomonal and antifungal activities. Twenty-one compounds irreversibly immobilized 100% sperm (MEC, 0.06-31.6 mM) while seven compounds exhibited multiple activities. Benzyl 4-(2-(piperidin-1-yl)ethyl) piperazine-1-(carbodithioate) (18) and 1-benzyl 4-(2-(piperidin-1-yl)ethyl)piperazine-1,4-bis(carbodithioate) (24) exhibited appreciable spermicidal (MEC, 0.07 and 0.06 mM), antifungal (MIC, 0.069-0.14 and >0.11 mM) and antitrichomonal (MIC, 1.38 and 0.14 mM) activities. The probable mode of action of these compounds seems to be through sulfhydryl binding which was confirmed by fluorescence labeling of sperm thiols.


Asunto(s)
Diseño de Fármacos , Piperazinas/química , Piperazinas/síntesis química , Inmovilizantes de los Espermatozoides/química , Inmovilizantes de los Espermatozoides/síntesis química , Tiocarbamatos/química , Tiocarbamatos/síntesis química , Antifúngicos/síntesis química , Antifúngicos/farmacología , Muerte Celular/efectos de los fármacos , Colorantes Fluorescentes/metabolismo , Células HeLa , Humanos , Lactobacillus/efectos de los fármacos , Masculino , Pruebas de Sensibilidad Microbiana , Piperazinas/farmacología , Inmovilizantes de los Espermatozoides/farmacología , Espermatozoides/efectos de los fármacos , Espermatozoides/metabolismo , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/metabolismo , Tiocarbamatos/farmacología , Trichomonas/efectos de los fármacos
16.
Food Chem ; 444: 138628, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38320335

RESUMEN

The chemical compositions, intermolecular interactions, and functional properties of guar germ proteins (GGP) were investigated at different extraction pH (7 to 11). The protein efficiency ratio, essential amino acid index (46.53), predicted biological value (39.02), nutritional index (42.67), and protein purity (91.69 %) were found to be highest at pH 9. The in-vitro protein digestibility of GGP sample was highest at pH 11. From SDS-PAGE, the band intensity (<10 kDa) became thinner with an increase in extraction pH from 7 to 9 and then thicker. Meanwhile, smallest particle size and weaker ionic and hydrogen bonds were found at pH 11. The ß-sheet content was more dominating in GGP samples. Moreover, higher denaturation temperatures of GGP samples indicated that protein molecules had a compact tertiary structure. Furthermore, the GGP extracted at pH 7 showed better functional properties. The principal component analysis suggested that pH 9 was more suitable for isolating GGP.


Asunto(s)
Aminoácidos , Cyamopsis , Aminoácidos/análisis , Cyamopsis/metabolismo , Proteínas , Aminoácidos Esenciales , Concentración de Iones de Hidrógeno
17.
J Food Sci ; 89(4): 2188-2201, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38369948

RESUMEN

Guar seed flour (GSF) has a high amount of carbohydrates, proteins, phytochemicals, and anti-nutritional factors (ANFs), which limits its use. To address this issue, the current study was undertaken to understand the effect of microwave (MW) irradiation on ANFs, phytochemicals, in vitro protein digestibility (IVPD), and functional attributes of GSF at varying power density (Pd: 1-3 W/g) and duration (3-9 min). The ANFs were determined using a colorimetric assay and a Fourier transform infrared spectrum. At 3 Pd-9 min, the maximum reduction in ANFs (tannin, phytic acid, saponin, and trypsin inhibitor activity) was observed. Higher Pd and treatment duration increased antioxidant activity and total phenolic content, except for total flavonoid content. Furthermore, compared to the control sample (78.38%), the IVPD of the GSF samples increased to 3.28% (3 Pd-9 min). An increase in Pd and duration of MW treatment improved the thermal and pasting properties of GSF samples up to 2 Pd-9 min. Due to inter- and intramolecular hydrogen bonding degradation, the relative crystallinity of the 3 Pd-9 min treated GSF sample was 30.58%, which was lower than that of the control (40.08%). In MW-treated samples, SEM images revealed smaller clusters with rough and porous structures. However, no noticeable color (ΔE) changes were observed in MW-treated samples. Aside from water absorption capacity and water solubility index, MW treatment reduced oil absorption capacity, foaming capacity, and emulsifying capacity. As demonstrated by principal component analysis, MW irradiation with moderate Pd (2-3) was more effective in reducing ANFs, retaining nutritional contents, and improving the digestible properties of GSF, which could be a potential ingredient for developing gluten-free products.


Asunto(s)
Cyamopsis , Microondas , Harina/análisis , Semillas/química , Fitoquímicos/análisis , Agua/análisis
18.
Chem Sci ; 15(2): 710-719, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38179533

RESUMEN

Xenobiotic aromatic water pollutants pose an extreme threat to environmental sustainability. Due to the lack of detectable functional groups in these compounds and scarcity of selective bio-recognition scaffolds, easy-to-use sensing strategies capable of on-site detection remain unavailable. Herein, to address this lacune, we entail a strategy that combines biosensor scaffolds with organic electronics to create a compact device for environmental aromatic pollution monitoring. As proof of principle, a sensor module capable of rapid, economic, reliable, and ultrasensitive detection of phenol down to 2 ppb (0.02 µM) was designed wherein biosensing protein MopR was coupled with an organic electrochemical transistor (OECT). For effective interfacing of the sensing scaffold MopR, graphene oxide (GO) nanosheets were optimized as a host immobilization matrix. The MopR-GO immobilized sensor module was subsequently substituted as the gate electrode with PEDOT:PSS serving as an organic semiconductor material. The resulting OECT sensor provided a favourable microenvironment for protein activity, maintaining high specificity. Exclusive phenol detection with minimal loss of sensitivity (<5% error) could be achieved in both complex pollutant mixtures and real environmental samples. This fabrication strategy that amalgamates biological biosensors with organic electronics harnesses the potential to achieve detection of a host of emerging pollutants.

19.
Int J Biol Macromol ; 267(Pt 2): 131545, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38614168

RESUMEN

Corn starch (CS) is a good alternative to synthetic polymers due to its sustainability; nevertheless, because of its weak tensile strength, the matrix requires another polymer. Therefore, 0.5 % (w/v) moringa gum (MG) was added. The purpose of this study was to assess how pine cone extract (PCE) affected the physiochemical and mechanical properties of corn starch and moringa gum (CS/MG) films and their use as UV-blocking composites. The findings suggest that the PCE improved the elongation at break from 3.27 % to 35.2 % while greatly reducing the tensile strength. The hydrogen bonding between CS/MG and PCE was visible in the FTIR spectra. The XRD graph indicated that the films were amorphous. In comparison to CS/MG films, PCE-incorporated edible films demonstrated significant UV-blocking ability indicating their potential as sustainable packaging material for light-sensitive food products.


Asunto(s)
Películas Comestibles , Embalaje de Alimentos , Pinus , Extractos Vegetales , Almidón , Rayos Ultravioleta , Embalaje de Alimentos/métodos , Almidón/química , Extractos Vegetales/química , Pinus/química , Moringa/química , Resistencia a la Tracción , Zea mays/química , Gomas de Plantas/química
20.
Front Reprod Health ; 6: 1330161, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38406668

RESUMEN

Mitogen-activated protein kinases (MAPKs) represent widely expressed and evolutionarily conserved proteins crucial for governing signaling pathways and playing essential roles in mammalian male reproductive processes. These proteins facilitate the transmission of signals through phosphorylation cascades, regulating diverse intracellular functions encompassing germ cell development in testis, physiological maturation of spermatozoa within the epididymis, and motility regulation at ejaculation in the female reproductive tract. The conservation of these mechanisms appears prevalent across species, including humans, mice, and, to a limited extent, livestock species such as bovines. In Sertoli cells (SCs), MAPK signaling not only regulates the proliferation of immature SCs but also determines the appropriate number of SCs in the testes at puberty, thereby maintaining male fertility by ensuring the capacity for sperm cell production. In germ cells, MAPKs play a crucial role in dynamically regulating testicular cell-cell junctions, supporting germ cell proliferation and differentiation. Throughout spermatogenesis, MAPK signaling ensures the appropriate Sertoli-to-germ cell ratio by regulating apoptosis, controlling the metabolism of developing germ cells, and facilitating the maturation of spermatozoa within the cauda epididymis. During ejaculation in the female reproductive tract, MAPKs regulate two pivotal events-capacitation and the acrosome reaction essential for maintaining the fertility potential of sperm cells. Any disruptions in MAPK pathway signaling possibly may disturb the testicular microenvironment homeostasis, sperm physiology in the male body before ejaculation and in the female reproductive tract during fertilization, ultimately compromising male fertility. Despite decades of research, the physiological function of MAPK pathways in male reproductive health remains inadequately understood. The current review attempts to combine recent findings to elucidate the impact of MAPK signaling on male fertility and proposes future directions to enhance our understanding of male reproductive functions.

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