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1.
Theor Appl Genet ; 136(11): 226, 2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37847385

RESUMEN

KEY MESSAGE: Lack of function of a D-genome adult plant resistance gene upon introgression into durum wheat. The wheat Lr34/Yr18/Sr57/Pm38/Ltn1 adult plant resistance gene (Lr34), located on chromosome arm 7DS, provides broad spectrum, partial, adult plant resistance to leaf rust, stripe rust, stem rust and powdery mildew. It has been used extensively in hexaploid bread wheat (AABBDD) and conferred durable resistance for many decades. These same diseases also occur on cultivated tetraploid durum wheat and emmer wheat but transfer of D genome sequences to those subspecies is restricted due to very limited intergenomic recombination. Herein we have introgressed the Lr34 gene into chromosome 7A of durum wheat. Durum chromosome substitution line Langdon 7D(7A) was crossed to Cappelli ph1c, a mutant derivative of durum cultivar Cappelli homozygous for a deletion of the chromosome pairing locus Ph1. Screening of BC1F2 plants and their progeny by KASP and PCR markers, 90 K SNP genotyping and cytology identified 7A chromosomes containing small chromosome 7D fragments encoding Lr34. However, in contrast to previous transgenesis experiments in durum wheat, resistance to wheat stripe rust was not observed in either Cappelli/Langdon 7D(7A) or Bansi durum plants carrying this Lr34 encoding segment due to low levels of Lr34 gene expression.


Asunto(s)
Basidiomycota , Triticum , Triticum/genética , Pan , Genes de Plantas , Plantas/genética , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética
2.
Theor Appl Genet ; 135(12): 4327-4336, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36173416

RESUMEN

KEY MESSAGE: Stripe rust resistance gene YrAet672 from Aegilops tauschii accession CPI110672 encodes a nucleotide-binding and leucine-rich repeat domain containing protein similar to YrAS2388 and both these members were haplotypes of Yr28. New sources of host resistance are required to counter the continued emergence of new pathotypes of the wheat stripe rust pathogen Puccinia striiformis Westend. f. sp. tritici Erikss. (Pst). Here, we show that CPI110672, an Aegilops tauschii accession from Turkmenistan, carries a single Pst resistance gene, YrAet672, that is effective against multiple Pst pathotypes, including the four predominant Pst lineages present in Australia. The YRAet672 locus was fine mapped to the short arm of chromosome 4D, and a nucleotide-binding and leucine-rich repeat gene was identified at the locus. A transgene encoding the YrAet672 genomic sequence, but lacking a copy of a duplicated sequence present in the 3' UTR, was transformed into wheat cultivar Fielder and Avocet S. This transgene conferred a weak resistance response, suggesting that the duplicated 3' UTR region was essential for function. Subsequent analyses demonstrated that YrAet672 is the same as two other Pst resistance genes described in Ae. tauschii, namely YrAS2388 and Yr28. They were identified as haplotypes encoding identical protein sequences but are polymorphic in non-translated regions of the gene. Suppression of resistance conferred by YrAet672 and Yr28 in synthetic hexaploid wheat lines (AABBDD) involving Langdon (AABB) as the tetraploid parent was associated with a reduction in transcript accumulation.


Asunto(s)
Aegilops , Basidiomycota , Aegilops/genética , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética , Mapeo Cromosómico , Leucina/genética , Genes de Plantas , Basidiomycota/fisiología , Poaceae/genética , Nucleótidos
3.
Plant Biotechnol J ; 19(2): 273-284, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32744350

RESUMEN

In the last 20 years, stem rust caused by the fungus Puccinia graminis f. sp. tritici (Pgt), has re-emerged as a major threat to wheat and barley production in Africa and Europe. In contrast to wheat with 60 designated stem rust (Sr) resistance genes, barley's genetic variation for stem rust resistance is very narrow with only ten resistance genes genetically identified. Of these, only one complex locus consisting of three genes is effective against TTKSK, a widely virulent Pgt race of the Ug99 tribe which emerged in Uganda in 1999 and has since spread to much of East Africa and parts of the Middle East. The objective of this study was to assess the functionality, in barley, of cloned wheat Sr genes effective against race TTKSK. Sr22, Sr33, Sr35 and Sr45 were transformed into barley cv. Golden Promise using Agrobacterium-mediated transformation. All four genes were found to confer effective stem rust resistance. The barley transgenics remained susceptible to the barley leaf rust pathogen Puccinia hordei, indicating that the resistance conferred by these wheat Sr genes was specific for Pgt. Furthermore, these transgenic plants did not display significant adverse agronomic effects in the absence of disease. Cloned Sr genes from wheat are therefore a potential source of resistance against wheat stem rust in barley.


Asunto(s)
Basidiomycota , Resistencia a la Enfermedad/genética , Hordeum , Enfermedades de las Plantas/genética , Hordeum/genética , Enfermedades de las Plantas/microbiología
5.
J Family Med Prim Care ; 13(5): 1747-1754, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38948598

RESUMEN

Introduction: We assessed the baseline knowledge and the improvement and retention of knowledge after attending diabetes self-management education (DSME) programs with respect to different socioeconomic status (SES). We also looked into the change in body mass index (BMI), blood pressure, and glycemic parameters after attending the DSME sessions. Materials and Methods: This was a retrospective, cohort study carried out via chart review based on data collected from manual or electronic medical records (EMR) and questionnaire responses of 160 adult patients with type 2 diabetes (T2D) who attended two DSME sessions with a gap of at least six months. Results: Baseline knowledge on diabetes was uniform (P = 0.06), irrespective of differences in SES, and DSME sessions significantly improved the knowledge in all socioeconomic classes (P value < 0.05 in each SES group). However, SES did have a significant influence on the finally acquired knowledge of diabetes as was evident from the final score after attending two DSME sessions. A significant number of patients (48.1%) from our cohort either improved or retained their knowledge of diabetes over a mean follow-up of 15.5 months. The BMI of our cohort was significantly reduced from baseline to final follow-up (P = 0.016). Conclusion: DSME sessions were effective in improving knowledge and awareness among T2D patients, irrespective of socioeconomic classes in Eastern India. The acquired knowledge from DSME sessions was retained over a long time.

6.
Nutrients ; 16(14)2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39064752

RESUMEN

Starting at 4 weeks of age, male and female C57BL/6J mice were provided with a semi-synthetic diet for a period of one year and then continued on the semi-synthetic diet with or without grape supplementation for the duration of their lives. During the course of the study, no variation of body weights was noted between the groups. At 2.5 years of age, the body-weight-to-tissue-weight ratios did not vary for the liver, colon, muscle, prostate, or ovary. However, relative to the standard diet, the body/kidney weight ratio was significantly lower in the male and female groups with grape-supplemented diets. With the mice provided with the standard diet, the BUN/creatinine ratios were 125 and 152 for males and females, respectively, and reduced to 63.7 and 40.4, respectively, when provided with the grape diet. A histological evaluation suggested that this may be due to enhanced/improved perfusion in the kidney as a preventive/protective effect. In response to the dietary grapes, an RNA seq analysis revealed up-regulation of 21 and 109 genes with male and female mice, respectively, with a corresponding down-regulation of 108 and 65 genes. The downward movement of the FPKM values in the males (alox5, btk, fga, fpr1, hmox1, lox, ltf, lyve1, marco, mmp8, prg4, s100a8/9, serpina3n, and vsig4) and upward movement of the FPKM values in the females (camp, cd300lf, cd72, fcgr4, fgr, fpr2, htra4, il10, lilrb4b, lipg, pilra, and tlr8) suggest beneficial kidney effects. The expression of some genes related to the immunological activity was also modulated by the grape diet, mainly downward in the males and upward in the females. The reactome pathway analysis, KEGG analysis, and GSEA normalized enrichment scores illustrate that several pathways related to immune function, collagenase degradation, extracellular matrix regulation, metabolism of vitamins and cofactors, pancreatic secretion, aging, and mitochondrial function were enriched in both the males and females provided with the grape diet. Overall, these results indicate that the long-term dietary consumption of grapes contributes to renal health and resilience against fibrosis and related pathologies.


Asunto(s)
Riñón , Ratones Endogámicos C57BL , Vitis , Animales , Femenino , Masculino , Riñón/metabolismo , Ratones , Dieta , Suplementos Dietéticos
7.
Cureus ; 15(6): e40179, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37431351

RESUMEN

INTRODUCTION: Oral semaglutide is a glucagon-like peptide-1 receptor agonist (GLP-1RA) class of antidiabetic medication. High costs and GI side effects are the major limitations of its widespread use. Some patients who were on a 14 mg dose of oral semaglutide self-prescribed an alternate-day schedule to mitigate GI side effects and to reduce the cost. METHODS: This retrospective observational cohort study evaluates the ambulatory glucose profile (AGP) data, extrapolated glycosylated hemoglobin (HbA1C), and BMI of 11 types of 2 diabetes mellitus (T2DM) while they were on an alternate-day 14 mg dose of oral semaglutide compared to their record while on a daily 7 mg dose. The AGP metrics (time-in-range (TIR), time-below-range (TBR), and time-above-range (TAR)) along with extrapolated HbA1C and BMI were analyzed. Statistical analysis was done using SPSS Statistics version 21.0. RESULTS: No statistically significant difference in the AGP metrics between the AGP profile of a daily 7 mg dose and the AGP profile of an alternate-day 14 mg dose of oral semaglutide was observed. Interestingly, a statistically significant progressive decline in BMI value was observed even on the alternate-day 14 mg dose when compared to the daily 7 mg dose. CONCLUSION: In this small cohort of patients, the metrics of short-term glycemic control and the extrapolated HbA1C values were similar for the daily 7 mg dose versus the alternate-day 14 mg dose of oral semaglutide. BMI showed progressive reduction which was statistically significant even with the alternate-day 14 mg dose of oral semaglutide.

8.
Cureus ; 15(4): e37065, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37153287

RESUMEN

Introduction Oral semaglutide, with a long half-life of seven days, is the first oral-based peptide drug and is used as an antidiabetic for the reduction of glycosylated hemoglobin (HbA1c). Oral semaglutide, like other glucagon-like peptide-1 receptor agonists (GLP1RAs), is costly and has gastrointestinal (GI) side effects, especially with a 14 mg dose. In the real world, some type 2 diabetes mellitus (T2DM) patients on 14 mg oral dose adopt an alternate-day strategy to minimize unwanted GI symptoms. In this study, we analyzed the ambulatory glucose profile (AGP) data of patients with T2DM who were on 14 mg alternate-day oral semaglutide therapy. Methods This retrospective observational study evaluated the AGP data of 10 patients on alternate-day dosing of 14 mg oral semaglutide. The AGP data over a period of 14 days on a single group of patients were analyzed without any control group or randomization and are presented as a case series. AGP monitoring, using Freestyle Libre Pro (Abbott, Illinois, United States), is a standard operating procedure of the endocrinology department for all T2DM patients who were put on oral semaglutide therapy. The AGP data of the glycemic parameters time-in-range (TIR), time-above-range (TAR), and time-below-range (TBR), were compared between the days when oral semaglutide was consumed (days-on-drug) versus the days when oral semaglutide was not consumed (days-off-drug). The statistical analysis was done with Statistical Package for Social Sciences (SPSS) version 21.0 (IBM Corp., Armonk, NY). Results We applied the Shapiro-Wilk test (sample size <50) for normality testing; the TIR values of days-on-drug and days-off-drug showed high p values (p =0.285 and 0.109), respectively. This indicated that TIR values days-on-drug and days-off-drug were normally distributed. Although, the distribution of TAR and TBR values days-on-drug and days-off-drug, were not normal as they had small p values (p< 0.05). Hence, further analysis of the paired set of data was done using the Wilcoxon signed-rank test. It revealed no difference in TIR, TAR, and TBR between the two groups (days-on-drug and days-off-drug). Conclusion Throughout the period of observation, the glycemic metrics (TIR, TAR, and TBR) remained steady with a 14 mg alternate-day oral semaglutide regimen.

9.
Nat Biotechnol ; 39(5): 561-566, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33398152

RESUMEN

Breeding wheat with durable resistance to the fungal pathogen Puccinia graminis f. sp. tritici (Pgt), a major threat to cereal production, is challenging due to the rapid evolution of pathogen virulence. Increased durability and broad-spectrum resistance can be achieved by introducing more than one resistance gene, but combining numerous unlinked genes by breeding is laborious. Here we generate polygenic Pgt resistance by introducing a transgene cassette of five resistance genes into bread wheat as a single locus and show that at least four of the five genes are functional. These wheat lines are resistant to aggressive and highly virulent Pgt isolates from around the world and show very high levels of resistance in the field. The simple monogenic inheritance of this multigene locus greatly simplifies its use in breeding. However, a new Pgt isolate with virulence to several genes at this locus suggests gene stacks will need strategic deployment to maintain their effectiveness.


Asunto(s)
Basidiomycota/genética , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética , Triticum/genética , Basidiomycota/patogenicidad , Mapeo Cromosómico , Fitomejoramiento , Enfermedades de las Plantas/microbiología , Transgenes/genética , Triticum/microbiología , Virulencia/genética
10.
Nat Commun ; 12(1): 3378, 2021 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-34099713

RESUMEN

The re-emergence of stem rust on wheat in Europe and Africa is reinforcing the ongoing need for durable resistance gene deployment. Here, we isolate from wheat, Sr26 and Sr61, with both genes independently introduced as alien chromosome introgressions from tall wheat grass (Thinopyrum ponticum). Mutational genomics and targeted exome capture identify Sr26 and Sr61 as separate single genes that encode unrelated (34.8%) nucleotide binding site leucine rich repeat proteins. Sr26 and Sr61 are each validated by transgenic complementation using endogenous and/or heterologous promoter sequences. Sr61 orthologs are absent from current Thinopyrum elongatum and wheat pan genome sequences, contrasting with Sr26 where homologues are present. Using gene-specific markers, we validate the presence of both genes on a single recombinant alien segment developed in wheat. The co-location of these genes on a small non-recombinogenic segment simplifies their deployment as a gene stack and potentially enhances their resistance durability.


Asunto(s)
Resistencia a la Enfermedad/genética , Proteínas NLR/genética , Plantas Modificadas Genéticamente/microbiología , Puccinia/patogenicidad , Triticum/microbiología , Cromosomas de las Plantas/genética , Genes de Plantas , Ingeniería Genética , Marcadores Genéticos , Fitomejoramiento/métodos , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Tallos de la Planta/microbiología , Plantas Modificadas Genéticamente/genética , Puccinia/aislamiento & purificación , Triticum/genética
11.
Indian J Endocrinol Metab ; 24(4): 301-305, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33088751

RESUMEN

BACKGROUND: The term "hijra" is used to describe eunuchs, intersex, and gender incongruent individuals from hijra community people in the Indian subcontinent. Various adversities, violence, and discrimination experienced by many of them might have adverse consequences on their quality of life (QOL). The present study was conducted to assess the QOL among adult gender incongruent individuals from the hijra community. METHODS: Data of thirty-seven hijra enrolled in the Endocrine outpatient clinic (hijra group) and thirty-seven healthy employees of the hospital (control group) were analyzed with regard to QOL. QOL was assessed by using the physical and mental health Short Form-36 (SF-36) health survey questionnaire. Results on continuous measurements were presented as mean ± SD and results on categorical measurements were presented in number and percent. Mann-Whitney U test or Student t-test was used to find the significance of study parameters between the two groups according to the data distribution. RESULTS: In the domain namely role limitation due to emotional problem, the hijra cohort had a statistically significantly lower score (66.4 ± 20.2) versus the control cohort (83.4 ± 23.7), P = 0.002. No difference was observed between two groups with regards to other QOL domains namely general health perception, physical functioning, role limitation due to physical problem, bodily pain, general mental health, social functioning, and vitality. CONCLUSIONS: QOL of the gender incongruent individuals from the hijra community included in this study and the control group comprising of hospital employees were almost similar, though the former had reported lower levels of emotional health issues than the latter.

12.
Indian J Endocrinol Metab ; 24(6): 525-531, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33643869

RESUMEN

CONTEXT: Gender incongruent individuals are exposed to unique stressors as a result of their minority social position. Poor social support has a further adverse impact on the lives and wellbeing of gender incongruent individuals. There is a paucity of scientific data from India on the socioeconomic status (SES) of gender incongruent community. AIMS: Aim of the study is to understand and estimate the social support, wellbeing, and SES of gender incongruent individuals in Eastern India. SUBJECTS AND METHODS: Data of 120 gender incongruent patients from the endocrinology outpatient department of a tertiary care hospital in eastern India were collected. We looked at demographic characteristics, social support, underlying psychiatric comorbidities, and SES. SES was calculated by the Kuppuswamy's socioeconomic status (KSS) scale based on occupation, education, and income. STATISTICAL ANALYSIS USED: Microsoft Word and Excel were used to generate tables. RESULTS: Most of the gender incongruent individuals were transfeminine. Almost half of them had no history of addiction. Most of them had good support from family and friends and very few (only 3%) had mental health problems. Calculation by KSS scale showed most of the study population lay in the upper middle or lower middle socioeconomic class. CONCLUSIONS: Strong support from friends and family appears a key factor for protection against psychiatric comorbidities and an all-round impact on the lives and wellbeing of the study population.

13.
J Am Chem Soc ; 130(16): 5414-5, 2008 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-18376826

RESUMEN

Oxidation of graphite may be carried out by reaction with meta-chloroperoxybenzoic acid to yield graphite epoxide. Scanning tunneling microscopy (STM) showed that the functionalization occurs at the edges rather than on the basal plane of the graphite. Quantification of the epoxide content is possible through the deepoxidation reaction using MeReO3/PPh3.

14.
Clin Neurophysiol ; 128(4): 622-634, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28231479

RESUMEN

OBJECTIVE: To investigate the prevalence and the temporal structure of bilateral coherence in physiological (PT) and essential (ET) hand tremor. METHODS: Triaxial accelerometric recordings from both hands in 30 healthy subjects and 34 ET patients were analyzed using spectral coherence and wavelet coherence methods. In 12 additional healthy subjects, the relation between the hand tremor and the chest wall acceleration was evaluated using partial coherence analysis. RESULTS: The majority of both PT and ET subjects displayed significant bilateral coherence. While in PT, bilateral coherence was most frequently found in resting hand position (97% of subjects), in ET the prevalence was comparable for resting (54%) and postural (49%-57%) positions. In both PT and ET, epochs of strong coherence lasting several to a dozen seconds were separated by intervals of insignificant coherence. In PT, bilateral coherence at the main tremor frequency (8-12Hz) was coupled with the ballistocardiac rhythm. CONCLUSION: The oscillations of the two hands are intermittently synchronized in both PT and ET. We propose that in postural PT, bilateral coherence at the main tremor frequency arises from transient simultaneous entrainment of the left and right hand oscillations to ballistocardiac forcing. SIGNIFICANCE: Bilateral coherence of hand kinematics provides a sensitive measure of synchronizing influences on the left and right tremor oscillators.


Asunto(s)
Temblor Esencial/fisiopatología , Lateralidad Funcional , Temblor/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Electromiografía , Femenino , Mano/inervación , Mano/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Movimiento
15.
J Phys Chem B ; 110(49): 24812-5, 2006 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-17149898

RESUMEN

Single-walled carbon nanotubes have been functionalized and the specific surface areas of the functionalized nanotubes measured. Contrary to expectations, functionalization leads to a decrease in specific surface area compared to that of the unfunctionalized nanotubes. Treatment with a concentrated 1:1 nitric/sulfuric acid mixture followed by high-temperature baking at 1000 degrees C was found to increase the specific surface area of the nanotubes. For the unfunctionalized SWNTs, this treatment increases the specific surface area (SSA) by 20%. In the case of SWNTs functionalized by n-butyl groups the increase in the SSA was nearly 2-fold with the value increasing from 410 (drying at 110 degrees C) to 770 m2/gm (acid and bake treatment followed by drying at 110 degrees C). For the ozonized SWNTs, the SSA increases more than 3-fold from 381 (drying at 110 degrees C) to 1068 m2/gm (acid and bake treatment followed by drying at 110 degrees C). SEM images indicate that the nanotubes rebundle in the solid state with an average bundle size of 10-30 nm. AFM studies show that the ozonized tubes have been cut to short bundles after ozonolysis. Hydrogen uptake studies carried out on the baked ozonized tubes led to a 3 wt % hydrogen uptake at 77 K and 30 bar.

16.
Soft Matter ; 2(10): 850-854, 2006 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-32680276

RESUMEN

Poly(acrylic acid) and alkyl modified poly(acrylic acid) nanoparticles were formed by the reverse microemulsion technique. Scanning electron microspectroscopy, zeta potential measurements and fluorescence spectroscopy were used for their characterization. It was observed that they are in the range 80-100 nm and their surface charge is pH dependent. The particles were assessed for their ability to extract drugs such as amitriptyline and bupivacaine from bulk fluid for their potential application as scavengers for overdosed drugs. In normal saline (0.9% NaCl) unmodified poly(acrylic acid) nanoparticles (per gram) extracted 81 mg amitriptyline and 62 mg bupivacaine in 5 minutes, whereas for the alkyl modified poly(acrylic acid) nanoparticles, extractions were 68 mg and 51 mg amitriptyline and bupivacaine respectively per gram of nanoparticles used.

17.
PLoS One ; 10(4): e0124475, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25875378

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0116813.].

18.
PLoS One ; 10(2): e0116813, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25710715

RESUMEN

Flies achieve supreme flight maneuverability through a small set of miniscule steering muscles attached to the wing base. The fast flight maneuvers arise from precisely timed activation of the steering muscles and the resulting subtle modulation of the wing stroke. In addition, slower modulation of wing kinematics arises from changes in the activity of indirect flight muscles in the thorax. We investigated if these modulations can be described as a superposition of a limited number of elementary deformations of the wing stroke that are under independent physiological control. Using a high-speed computer vision system, we recorded the wing motion of tethered flying fruit flies for up to 12,000 consecutive wing strokes at a sampling rate of 6250 Hz. We then decomposed the joint motion pattern of both wings into components that had the minimal mutual information (a measure of statistical dependence). In 100 flight segments measured from 10 individual flies, we identified 7 distinct types of frequently occurring least-dependent components, each defining a kinematic pattern (a specific deformation of the wing stroke and the sequence of its activation from cycle to cycle). Two of these stroke deformations can be associated with the control of yaw torque and total flight force, respectively. A third deformation involves a change in the downstroke-to-upstroke duration ratio, which is expected to alter the pitch torque. A fourth kinematic pattern consists in the alteration of stroke amplitude with a period of 2 wingbeat cycles, extending for dozens of cycles. Our analysis indicates that these four elementary kinematic patterns can be activated mutually independently, and occur both in isolation and in linear superposition. The results strengthen the available evidence for independent control of yaw torque, pitch torque, and total flight force. Our computational method facilitates systematic identification of novel patterns in large kinematic datasets.


Asunto(s)
Drosophila melanogaster/fisiología , Movimiento , Alas de Animales/fisiología , Animales , Fenómenos Biomecánicos , Simulación por Computador
19.
J Cosmet Sci ; 55 Suppl: S1-17, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15645085

RESUMEN

A "touch me not" plant folding up rapidly upon being attacked or microbes depositing on teeth or ocean vessels even under hostile conditions are examples in nature that provide inspiration for developing new classes of personal care release or deposition systems. In this paper, development of such systems based on polymer/surfactant colloid chemistry is explored for achieving transport and release of cosmetic and pharmaceutical molecules at desired rates at desired sites. The successful development of products depends upon understanding and utilizing key interactions among surfactants, polymers and hybrid polymers that are relevant to personal care products. Thus, the absorbed layers or tethers on the particulates can be manipulated for desired dispersion of actives or depositions on substrate under any and all conditions. New hybrid polymers and nanogels have been synthesized for tuning up nanodomains that can extract and deliver at will cosmetics/drugs/toxins by perturbing pH, temperature or ionic strength of the system. Particularly, hydrophobically modified polymers have features of both polymers and surfactants and due to the associative nature of the hydrophobic groups, such polymers can form intramolecular nanodomains for performing carrier functions. Nanogels developed recently include that of polyacrylamide, poly(acrylic acid) and starch nanogels modified for extraction and subsequent slow release of fragrances and overdosed toxic drugs. Binding and release processes were investigated using surface plasmon resonance and fluorescence spectroscopies, powerful techniques for monitoring short term and long term changes.


Asunto(s)
Cosméticos/química , Preparaciones para el Cabello/química , Nanoestructuras/química , Polímeros/química , Tensoactivos/química , Humanos , Concentración de Iones de Hidrógeno , Modelos Moleculares , Tensión Superficial , Viscosidad
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