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1.
Chemistry ; 29(1): e202202677, 2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36250277

RESUMEN

Tuning the redox potential of commonly available photocatalyst to improve the catalytic performance or expand its scope for challenging synthetic conversions is an ongoing demand in synthetic chemistry. Herein, the excited state properties and redox potential of commercially available [Ru(bpy)3 ]2+ photocatalyst were tuned by modifying the structure of the bipyridine ligands with electron-donating/withdrawing units. The visible-light-mediated photoredox phosphorylation of tertiary aliphatic amines was demonstrated under mild conditions. A series of cross-dehydrogenative coupling reactions were performed employing the RuII complexes as photocatalyst giving the corresponding α-aminophosphinoxides and α-aminophosphonates via carbon-phosphorus (C-P) bond formation.

2.
Angew Chem Int Ed Engl ; 62(44): e202312600, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37654187

RESUMEN

The design of efficient heavy atom-free triplet photosensitizers (PSs) based on through bond charge transfer (TBCT) features is a formidable challenge due to the criteria of orthogonal donor-acceptor geometry. Herein, we propose using parallel (face-to-face) conformation carbazole-bodipy donor-acceptor dyads (BCZ-1 and BCZ-2) featuring through space intramolecular charge transfer (TSCT) process as efficient triplet PS. Efficient intersystem crossing (ΦΔ =61 %) and long-lived triplet excited state (τT =186 µs) were observed in the TSCT dyad BCZ-1 compared to BCZ-3 (ΦΔ =0.4 %), the dyad involving TBCT, demonstrating the superiority of the TSCT approach over conventional donor-acceptor system. Moreover, the transient absorption study revealed that TSCT dyads have a faster charge separation and slower intersystem crossing process induced by charge recombination compared to TBCT dyad. A long-lived charge-separated state (CSS) was observed in the BCZ-1 (τCSS =24 ns). For the first time, the TSCT dyad was explored for the triplet-triplet annihilation upconversion, and a high upconversion quantum yield of 11 % was observed. Our results demonstrate a new avenue for designing efficient PSs and open up exciting opportunities for future research in this field.

3.
Pak J Pharm Sci ; 36(6): 1823-1829, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38124423

RESUMEN

Anxiolytic effect of ethanol, hexane extracts and pure compounds ß- sito sterol glucoside and bergenin isolated from Adenanthera pavonina AP (Fabaceae) and Peltophorum pterocarpum PP (Fabaceae) leaves were monitored in this study. Mice were treated with dose of 125mg/kg body weight of ethanol and hexane leaves extracts of both tested plants while, 5mg/kg body weight of ß-sito sterol glucoside and 25mg/kg body weight of bergenin. The effect was monitored by hole board test, forced swimming test, open field apparatus and stationary rod test. Results from neuropharmacological effects revealed that ethanol extract of AP leaves and hexane extract of PP leaves had significant anxiolytic (forced swimming test) exploratory (head dip and open field test) and neuro activator activity (stationary rod test) at tested dose. The greatest anti-depressant and anxiolytic effect was found in ethanol extract of AP leaves when compared to all treated drugs. A part from memory enhancing effects, diazepam treated mice also exhibited anxiolytic and antidepressant effects and found comparable with ethanol extract of AP. These findings may clarify the impact of ethanol, hexane extracts and pure substances ß-sitosterol glucoside and bergenin at tested concentrations, as well as their potential to treat the Parkinson's and related disorders as an alternative therapy.


Asunto(s)
Ansiolíticos , Fabaceae , Ratones , Animales , Ansiolíticos/farmacología , Ansiolíticos/uso terapéutico , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Hexanos , Depresión/tratamiento farmacológico , Etanol/farmacología , Ansiedad/tratamiento farmacológico , Peso Corporal , Glucósidos/farmacología , Esteroles/farmacología , Conducta Animal
4.
Phys Chem Chem Phys ; 24(35): 20901-20912, 2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36047252

RESUMEN

Herein, a series of compact anthracene carboxyimide (ACI) based donor-acceptor dyads were prepared by substituting bulky aryl moieties with various electron-donating ability to study the triplet-excited state properties. The ISC mechanism and triplet yield of the dyads were successfully tuned via structural manipulation. Efficient ISC (ΦΔ ≈ 99%) and long-lived triplet state (τT ≈ 122 µs) was observed for the orthogonal anthracene-labeled ACI derivative compared to the Ph-ACI and NP-ACI dyads, which showed fast triplet state decay (τT ≈ 7.7 µs). Femtosecond transient absorption study demonstrated the ultrafast charge separation (CS) and efficient charge recombination (CR) in the orthogonal dyads and ISC occurring via spin-orbit charge transfer (SOCT) mechanism (AN-ACI: τCS = 355 fs, τCR = 2.41 ns; PY-ACI: τCS = 321 fs, τCR = 1.61 ns), while in Ph-ACI and NP-ACI dyads triplet populate following the normal ISC channel (nπ* → ππ* transition), no CS was observed. We found that the attachment of suitable aryl donor moiety (AN- or PY-) to the ACI core can ensure the insertion of the intermediate triplet state, resulting in a small energy gap among charge separated state (CSS) and triplet state, which leads to efficient ISC in these derivatives. The SOCT-ISC-based AN-ACI dyad was confirmed to be a potent photodynamic therapeutic reagent; an ultra-low IC50 value (0.27 nM) that was nearly 214 times lower than that of the commercial Rose Bengal photosensitizer (57.8 nM) was observed.


Asunto(s)
Electrones , Fármacos Fotosensibilizantes , Antracenos , Indicadores y Reactivos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología
5.
Sensors (Basel) ; 23(1)2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36616697

RESUMEN

Since several Internet of Things (IoT) applications have been widely deployed on unstable wireless networks, such as the Delay Tolerant Network (DTN), data communication efficiency in DTN remains a challenge for IoT applications. Vehicular Delay Tolerant Network (VDTN) has become one of DTN's potential applications, in which the network experiences connectivity interruption due to the lack of an end-to-end relay route. VDTNs focus on node cooperation to achieve this goal. As a result, it is essential to ensure that almost all network nodes adopt the protocol to preserve network performance. This is a challenging task since nodes may diverge from the basic protocol to optimize their effectiveness. This article presents an Efficient Monitoring System (EMS) to detect and respond to just selfish nodes to minimize their entire network and data communication efficacy. The scheme is based on a network-wide cooperative sharing of node reputation. It is also necessary to increase overall network efficiency by tracking selfish nodes. The NS-2 simulator is used to run this experimental setup. Simulation results indicate that the proposed scheme performs better in terms of probability of package delivery, package delivery delay, energy consumption, and amount of packet drops. For 80% selfish nodes in the network, the packet delivery of EMS is 37% and 31% better than SOS and IPS. Similarly, the average delivery delay of EMS is 22% and 18% lower than SOS and IPS when 80% selfish nodes are incorporated in the network.


Asunto(s)
Internet de las Cosas , Redes de Comunicación de Computadores , Tecnología Inalámbrica , Algoritmos , Simulación por Computador
6.
Chemistry ; 27(17): 5521-5535, 2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33400310

RESUMEN

Perylenebisimide (PBI)-anthracene (AN) donor-acceptor dyads/triad were prepared to investigate spin-orbit charge-transfer intersystem crossing (SOCT-ISC). Molecular conformation was controlled by connecting PBI units to the 2- or 9-position of the AN moiety. Steady-state, time-resolved transient absorption and emission spectroscopy revealed that chromophore orientation, electronic coupling, and dihedral angle between donor and acceptor exert a significant effect on the photophysical property. The dyad PBI-9-AN with orthogonal geometry shows weak ground-state coupling and efficient intersystem crossing (ISC, ΦΔ =86 %) as compared with PBI-2-AN (ΦΔ =57 %), which has a more coplanar geometry. By nanosecond transient absorption spectroscopy, a long-lived PBI localized triplet state was observed (τT =139 µs). Time-resolved EPR spectroscopy demonstrated that the electron spin polarization pattern of the triplet state is sensitive to the geometry and number of AN units attached to PBI. Reversible and stepwise generation of near-IR-absorbing PBI radical anion (PBI-⋅ ) and dianion (PBI2- ) was observed on photoexcitation in the presence of triethanolamine, and it was confirmed that selective photoexcitation at the near-IR absorption bands of PBI.- is unable to produce PBI2- .

7.
Pak J Pharm Sci ; 34(5): 1707-1713, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34803006

RESUMEN

Among respiratory complications, cough is an important defensive pulmonary reflex that removes fluids, irritants or foreign substances from the respiratory tract. Rosa damascene Mill, petal extract is a traditional medicine and reported to use in the management of cough. In the present study rose petals extract samples were used to prepare natural antitussive cough syrups containing ivy leaf extract to observe synergistic effect of rose water in managing coughing in rats. Four cough formulations (A1, A2, A3 and A4) were prepared. The antitussive activity was observed at three dosage levels; 5ml, 10ml and 15ml. Cough was induced by the standard procedure using sulfur dioxide gas and ammonia. The antitussive activity was recorded by observing the coughing bouts. The result indicated that all formulations had a good effect on cough reduction at 90min but comparing the effect of formulations in all doses formulations, A2 followed by A3 and A4 at 30 minute time interval which is good in comparison with standard Diphenhydramine HCL and Dextromethorphan HBr 10ml in sulfur dioxide gas and ammonia induced cough. Hence, the results of the present study indicated the synergistic effect of rose water in the management of cough ailments.


Asunto(s)
Antitusígenos/química , Tos/inducido químicamente , Composición de Medicamentos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Rosa/química , Animales , Tos/tratamiento farmacológico , Formas de Dosificación , Relación Dosis-Respuesta a Droga , Flores/química , Humanos , Ratas , Ratas Wistar , Dióxido de Azufre/toxicidad
8.
Chemistry ; 26(65): 14912-14918, 2020 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-32567099

RESUMEN

Zinc(II) bis(dipyrrin) complexes, which feature intense visible absorption and efficient symmetry breaking charge transfer (SBCT) are outstanding candidates for photovoltaics but their short lived triplet states limit applications in several areas. Herein we demonstrate that triplet excited state dynamics of bis(dipyrrin) complexes can be efficiently tuned by attaching electron donating aryl moieties at the 5,5'-position of the complexes. For the first time, a long lived triplet excited state (τT =296 µs) along with efficient ISC ability (ΦΔ =71 %) was observed for zinc(II) bis(dipyrrin) complexes, formed via SBCT. The results revealed that molecular geometry and energy gap between the charge transfer (CT) state and triplet energy levels strongly control the triplet excited state properties of the complexes. An efficient triplet-triplet annihilation upconversion system was devised for the first time using a SBCT architecture as triplet photosensitizer, reaching a high upconversion quantum yield of 6.2 %. Our findings provide a blueprint for the development of triplet photosensitizers based on earth abundant metal complexes with long lived triplet state for revolutionary photochemical applications.

9.
J Environ Manage ; 272: 111024, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32854874

RESUMEN

Home to one-fourth of the world's population and ranked amongst the fastest growing economies, the South Asian countries are marred with the predicament of inexorable pollution. Amidst the growing pollutants, ground-level ozone has become an important component in understanding health, and productivity of agricultural crops. In this regard spatio-temporal analysis of tropospheric ozone for wheat, rice and cotton crops was carried out. Followed-up with a multivariate regression model; establishing a statistical relationship between tropospheric ozone (TO) and crop productivity. The results indicate that predominantly ozone is increasing, with a significant trend visible in all crop growing seasons. Observations indicate higher concentrations of TO in the rice & cotton growing seasons, with a seasonal average of 68 ppb, compared to wheat growing season (55 ppb). Regression results specify that with an increase of 1% in tropospheric ozone concentration within the study area; crop productivity decreases for cotton (-4.0%), rice (-2.3%), and wheat (-0.7%). Furthermore, with the presence of the dominant tropospheric ozone in the regression model, the temperature's impact on productivity becomes statistically inconsequential.


Asunto(s)
Contaminantes Atmosféricos/análisis , Ozono/análisis , Cambio Climático , Productos Agrícolas , India , Estaciones del Año
10.
Pak J Pharm Sci ; 30(6): 2101-2108, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29175779

RESUMEN

Monosodium urate monohydrate crystals are deposited in peripheral joints causing gout and elicit an intense localized inflammatory attack whereas in collecting ducts and medullary interstitium as a urinary calculi which causes dysuria, nausea and hematuria. The purpose of present study is to observe possible growth patterns of monosodium urate monohydrate crystals. The crystals were grown in test tubes by single diffusion gel technique and were observed at 7th, 14th, 21st, 28th and 40th day. Needle and spherulite type crystals were observed at 14th day, while arboresque, crystal sheaves, densely branched, dumbbell, mushroom type spherulites, plumose and hexagonal prismatic crystals were observed for the first time. After 40th day complete spherulites were observed with their aggregates. The crystals were characterized by Scanning Electron Microscopy, Energy-Dispersive X-ray and Fourier Transform infra Red spectroscopies. The pattern of MSUM will be helpful to determine the role of different natural products in the modulation, inhibition or promotion of these crystals by affecting the shape, size, transparency, approximate number and total mass of growing crystals. In case of inhibition or modulation it will be helpful for evaluation the prophylactic management whereas the promotion of the crystal will give an idea about the risk factors of gout and kidney stones.


Asunto(s)
Gota/metabolismo , Cálculos Renales/química , Ácido Úrico/química , Cristalización , Geles , Humanos , Microscopía Electrónica de Rastreo , Silicatos/química , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Factores de Tiempo
11.
Pak J Pharm Sci ; 30(5): 1733-1742, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29084696

RESUMEN

Three commonly used legumes, Macrotyloma uniflorum (Lam.) Verdc., Phaseolus lunatus Linn., and Phaseolus vulgaris Linn., were subjected to determine their minerals and phytic acid contents to correlate their nutritional and medicinal properties. To quantify essential minerals, atomic absorption spectroscopic method, while for phytic acid estimation, spectrophotometric method was used. Presence of Fe, Mg, Mn, P and Zn were recorded in good quantities, Ca and Cu in moderate, while K in small quantity in the seed flours of all the three tested legumes. Maximum Fe and Zn content (0.38 and 0.40 mg/g) were recorded in P. vulgaris, while M. uniflorum delivered high content of Mg, Mn, P and Ca (0.21, 0.20, 77.94 and 0.04 mg/g) and 0.04 mg/g Cu was recorded in P. lunatus. The highest level of phytic acid (37.00 mg/g) was recorded in M. uniflorum at 519 nm. The estimated quantities of minerals and phytic acid provide a good opportunity to draw a conclusion that all the three tested legumes could potentially be used as food to achieve nutritional and health related functional benefits.


Asunto(s)
Fabaceae/química , Frutas/química , Minerales/análisis , Valor Nutritivo , Ácido Fítico/análisis , Ácido Fítico/farmacología , Fabaceae/clasificación , Frutas/clasificación , Phaseolus/química , Espectrofotometría Atómica
12.
J Org Chem ; 81(2): 587-94, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26694534

RESUMEN

Efficient thiol-activated triplet-triplet annihilation (TTA) upconversion system was devised with maleimide-caged perylene (Py-M) as the thiol-activatable triplet acceptor/emitter and with diiodoBodipy as the triplet photosensitizer. The photophysical processes were studied with steady-state UV-vis absorption spectroscopy, fluorescence spectroscopy, electrochemical properties, and nanosecond transient absorption spectroscopy. The triplet acceptor/emitter Py-M shows week fluorescence (ΦF = 0.8%), and no upconversion (ΦUC = 0%) was observed. The quenching of fluorescence of Py-M is due to photoinduced electron-transfer (PET) process from perylene to maleimide-caging unit, which quenches the singlet excited state of perylene. The fluorescence of Py-M was enhanced by 200-fold (ΦF = 97%) upon addition of thiols such as 2-mercaptoethanol, and the ΦUC was increased to 5.9%. The unique feature of this thiol-activated TTA upconversion is that the activation is based on addition reaction of the thiols with the caged acceptor/emitter, and no side products were formed. The previously reported cleavage approach gives side products which are detrimental to the TTA upconversion. With nanosecond transient absorption spectroscopy, we found that the triplet excited state of Py-M was not quenched by any PET process, which is different from singlet excited state (fluorescence) of Py-M. The results are useful for study of the triplet excited states of organic chromophores and for activatable TTA upconversion.

13.
Photochem Photobiol Sci ; 15(11): 1358-1365, 2016 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-27722418

RESUMEN

Fluorescent molecular probes based on photo-induced electron transfer (PET) are well-known for which fluorescence is efficiently tuned OFF/ON by a PET process. Now we demonstrate that the triplet excited state of the probes is unable to be quenched by PET, which is in stark contrast to the singlet excited state (fluorescence). This conclusion was proved by the preparation of a fluorescent molecular probe BDP-DPA, which shows enhanced fluorescence upon addition of a Zn(ii) salt. With fluorescence spectroscopy, nanosecond transient absorption spectroscopy and electrochemical studies, we found that the triplet excited state of BDP-DPA was not quenched by any PET process, although the singlet excited state (fluorescence) of BDP-DPA was quenched. The results are useful for the study of the triplet excited states of organic chromophores and for designing external stimuli-activatable triplet photosensitizers for triplet-triplet annihilation upconversion and photodynamic therapy.


Asunto(s)
Compuestos de Boro/química , Colorantes Fluorescentes/química , Sondas Moleculares/química , Procesos Fotoquímicos , Electrones , Fármacos Fotosensibilizantes
14.
Pak J Pharm Sci ; 29(6): 2129-2139, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28375136

RESUMEN

About 12% of world population is affected by different forms of urolithiasis in which the recurrence rate in female is 47-60% and in male is 70-80%. According to WHO 75% people rely on traditional medicines for the prevention and cure of different ailments. Similarly, the majority of the world population use a number of plants to treat problems related to the urinary tract system in which urolithiasis is the major cause. The aim of the review is to collect the data of the plants used in different parts and cultures of the world against urolithiasis with their parts, mode of preparation, dosage and administration. A literature review was conducted for traditionally used antiurolithiatic plants. The articles mentioning plant, parts, mode of preparation, dose and route of administration were selected. This information was extracted to compose Mono and Poly herbal antiurolithiatic formulations used in Appalachia (region in Eastern United States), Canada, India, Iran, Israel, Italy, Jordan, Latin America, Pakistan, Turkey and Yemen. The review provides an important data about plants used as antiurolithiatic in different parts of the world. The information not only useful for common people, but also for the scientific community to carry out further phytochemical, pharmacological and toxicological studies for the discovery of new, effective and safer molecules against urolithiasis.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud/etnología , Medicina Tradicional , Extractos Vegetales/uso terapéutico , Urolitiasis/tratamiento farmacológico , Agentes Urológicos/uso terapéutico , Características Culturales , Composición de Medicamentos , Etnobotánica , Femenino , Humanos , Masculino , Fitoterapia , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Agentes Urológicos/química , Agentes Urológicos/aislamiento & purificación
15.
J Org Chem ; 80(6): 3036-49, 2015 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-25710451

RESUMEN

2,6-diiodoBodipy-perylenebisimide (PBI) dyad and triad were prepared, with the iodoBodipy moiety as the singlet/triplet energy donor and the PBI moiety as the singlet/triplet energy acceptor. IodoBodipy undergoes intersystem crossing (ISC), but PBI is devoid of ISC, and a competition of intramolecular resonance energy transfer (RET) with ISC of the diiodoBodipy moiety is established. The photophysical properties of the compounds were studied with steady-state and femtosecond/nanosecond transient absorption and emission spectroscopy. RET and photoinduced electron transfer (PET) were confirmed. The production of the triplet state is high for the iodinated dyad and the triad (singlet oxygen quantum yield ΦΔ = 80%). The Gibbs free energy changes of the electron transfer (ΔGCS) and the energy level of the charge transfer state (CTS) were analyzed. With nanosecond transient absorption spectroscopy, we confirmed that the triplet state is localized on the PBI moiety in the iodinated dyad and the triad. An exceptionally long lived triplet excited state was observed (τT = 150 µs) for PBI. With the uniodinated reference dyad and triad, we demonstrated that the triplet state localized on the PBI moiety in the iodinated dyad and triad is not produced by charge recombination. These information are useful for the design and study of the fundamental photochemistry of multichromophore organic triplet photosensitizers.

16.
Clin Exp Rheumatol ; 33(3): 347-53, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25897997

RESUMEN

OBJECTIVES: B-cell depletion using rituximab (RTX) has proven efficacy in patients with RA. Long-term effects on the B-cell system after single and repeated treatments are sparse. Our aim was to study the effect of multiple courses of rituximab to evaluate its impact on repeated B-cell re-population capacity. METHODS: Two cohorts, altogether 20 patients with RA were included in an open label extension study with RTX. Cohort 1 received one cycle RTX and was followed for up to 7 years. In cohort 2 patients were studied under up to 5 cycles of RTX. Immunophenotyping was performed before therapy and during follow-up. RESULTS: After a single therapy with RTX (cohort 1) the frequency of pre-switch (MZ-like) B cells were significantly reduced during the follow-up of 7 years and absolute numbers slowly repopulated to nearly 50% of baseline value without numerical normalisation. The acquisition of mutations in Ig receptors of pre-switch (MZ-like) memory B cells was also significantly reduced 10 years after one course. In contrast, absolute numbers of (classical) post-switch B cells tended to normalise to baseline values after 7 years. Analysing B-cell repopulation capacities after multiple cycles revealed (cohort 2) a comparable repopulation pattern after each cycle with no substantial further impact on memory B cells. CONCLUSIONS: A single therapy with RTX leads to long-term changes in the memory B-cell compartment particularly in pre-switch memory B cells. Multiple cycles of RTX show a comparable repopulation pattern after each cycle with no additional cumulative effect on memory B cells.


Asunto(s)
Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Antirreumáticos/administración & dosificación , Artritis Reumatoide/tratamiento farmacológico , Subgrupos de Linfocitos B/efectos de los fármacos , Adulto , Artritis Reumatoide/sangre , Artritis Reumatoide/diagnóstico , Subgrupos de Linfocitos B/inmunología , Esquema de Medicación , Femenino , Humanos , Memoria Inmunológica/efectos de los fármacos , Inmunofenotipificación , Infusiones Parenterales , Masculino , Persona de Mediana Edad , Fenotipo , Rituximab , Factores de Tiempo , Resultado del Tratamiento
17.
PLoS One ; 19(4): e0299454, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38625894

RESUMEN

This paper develops an outsourcing collaboration model from a firm's perspective operating in a developing economy. The model considers that producers of the final goods residing in a developed country, and operators of manufacturing plants in a developing country collaborate with each other. The final goods producer supplies headquarter services for the production of intermediate goods in the developing country. The operators of manufacturing plants also supply their services in the domestic economy. This arrangement leads to foreign outsourcing collaborations (FOC) between firms of developed country and developing country. The operators of manufacturing plant maximize revenue subject to the cost constraint. The first order conditions suggests that an increase in wages of skilled labor, price of domestic inputs, and cost of production deter FOC. On the other hand, an increase in demand for and price of foreign headquarter services increases the FOC. Empirical analysis based on data collected from 217 clothing (textile and apparel) firms in the city of Faisalabad (Pakistan) reveals that an increase in wage to labor-productivity ratio reduces FOC. An improvement in skilled of the labor and foreign headquarter services give rise to FOC, whereas an increase in economies-of-scope enhances FOC. Additionally, an inverted U-shaped relationship is found between the cost of production and FOC, which shows that at the initial stage, the firm's cost of production increases with an increase in the level of FOC, but soon after the tipping point, the firm's cost starts decreasing with a further increase in FOC.


Asunto(s)
Servicios Externos , Industria Textil , Humanos , Pakistán , Comercio , Salarios y Beneficios
18.
Chem Commun (Camb) ; 60(17): 2385-2388, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38321968

RESUMEN

We present a red light-activated zincII bis(dipyrrin) symmetry breaking charge transfer (SBCT) architecture, showing a large molar absorption coefficient (ε = 15.4 × 104 M-1 cm-1), high reactive singlet oxygen generation efficiency (ΦΔ ≈ 0.8) and long-lived triplet state (τT = 150 µs) compared to the donor-acceptor analogue dipyrrin-BF2 complex, highlighting the superiority of the SBCT approach. For the first time, we demonstrated the potential of a SBCT scaffold in red-light-induced methyl methacrylate (MMA) polymerization, using a dual photocatalyst excitation approach.

19.
Heliyon ; 10(4): e26126, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38384558

RESUMEN

Poly-herbal therapies for chronic diseases like diabetes mellitus (DM) have been practiced in south Asia for centuries. One of such therapies comprises of Hordeum vulgare, Elettaria cardamomum and Cicer arietinum that have shown encouraging therapeutic potential in the treatment of diabetes and obesity. Therefore, poly-herbal granules (PHGs) of this formula were developed and investigated for their anti-diabetic and anti-obesity potential in obese-diabetic rats. The developed PHGs were chemical characterized and the virtual molecular docking was performed by Discovery studio visualizer (DSV) software. For in-vivo experiment, obesity in rats was induced with high-fat high-sugar diet. After that, diabetes was induced by alloxan monohydrate 150 mg/kg i.p. injection. The diseased rats were treated with PHGs at 250, 500 and 750 mg/kg/day for four weeks. GC-MS analysis of PHGs demonstrated the presence of 1,3-Benzenedicarboxylic acid bis(2-ethylhexyl) ester and 1,2-Benzenedicarboxylic acid di-isooctyl ester and phenol, 2,4-bis(1,1-dimethylethyl). Molecular docking of these compounds demonstrated higher binding energies with receptor than metformin against α-amylase and α-glucosidase. PHGs exhibited a decline in body weight, HbA1c, hyperlipidemia, hyperglycemia, and insulin resistance in diseased rats. The histopathological examination revealed that PHGs improved the alloxan-induced damage to the pancreas. Furthermore, PHGs increased the SOD, CAT and GSH while and the decreased the level of MDA in the liver, kidney and pancreas of diseased rats. Additionally, the PHGs had significantly downregulated the TNF-α and NF-κB while upregulated the expression of NrF-2. The current study demonstrated that the PHGs exhibited anti-diabetic and anti-obesity potential through amelioration of oxidative stress, NF-κB, TNF-α, and NrF-2 due to the presence of different phytochemicals.

20.
Int J Biol Macromol ; 276(Pt 2): 133841, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39032888

RESUMEN

This study aims to design and optimize ondansetron (OND) gastro-retentive floating minitablets for better and prolonged control of postoperative nausea and vomiting (PONV) with improved patient compliance. Minitablets were directly compressed and encapsulated in a size 2 capsule shell with an overall dose of 24 mg. Central composite design (CCD) was applied keeping one cellulose ether derivative HPMC K15M and Carbopol 971 as variable and used as swelling and rate retarding agents. The other cellulose derivative i.e. sodium carboxymethyl cellulose, along with mannitol, sodium bicarbonate, and talc, were used in fixed quantities. The floating lag time, total floating time, swelling index, in-vitro drug release, and zero-order (RSQ value), were critical quality parameters. The optimized formulation (Fpred) was evaluated for all critical parameters, along with surface morphology, thermal stability, chemical interaction, and accelerated stability. The in silico PBPK modeling was applied to compare the bioavailability of Fpred with reference OND immediate-release tablets. The numerical optimization model predicted >90 % drug release with zero-order at 12 h. In silico PBPK modeling revealed comparable relative bioavailability of Fpred with the reference formulation. The gastroretentive floating minitablets of OND were successfully designed for prolonged emesis control in patients receiving chemotherapeutic agents.


Asunto(s)
Celulosa , Preparaciones de Acción Retardada , Liberación de Fármacos , Ondansetrón , Comprimidos , Ondansetrón/farmacocinética , Ondansetrón/química , Ondansetrón/administración & dosificación , Preparaciones de Acción Retardada/farmacocinética , Celulosa/análogos & derivados , Celulosa/química , Celulosa/farmacocinética , Humanos , Acrilatos/química , Acrilatos/farmacocinética , Química Farmacéutica/métodos , Disponibilidad Biológica , Composición de Medicamentos , Resinas Acrílicas/química , Modelos Biológicos
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