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1.
Molecules ; 29(11)2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38893547

RESUMEN

Hemorrhoid disease is a common anorectal disorder affecting populations worldwide, with high prevalence, treatment difficulties, and considerable treatment costs. Compared to other treatment options, medical therapy for hemorrhoids offers minimal harm, more dignity to patients, and is more economical. Unfortunately, there are few chemical hemorrhoid medications available clinically, which makes the search for efficacious, cost-effective, and environmentally friendly new medication classes a focal point of research. In this context, searching for available natural products to improve hemorrhoids exhibits tremendous potential. These products are derived from nature, predominantly from plants, with a minor portion coming from animals, fungi, and algae. They have excellent coagulation pathway regulation, anti-inflammatory, antibacterial, and tissue regeneration activities. Therefore, we take the view that they are a class of potential hemorrhoid drugs, prevention products, and medication add-on ingredients. This article first reviews the factors contributing to the development of hemorrhoids, types, primary symptoms, and the mechanisms of natural products for hemorrhoids. Building on this foundation, we screened natural products with potential hemorrhoid improvement activity, including polyphenols and flavonoids, terpenes, polysaccharides, and other types.


Asunto(s)
Productos Biológicos , Hemorroides , Hemorroides/tratamiento farmacológico , Humanos , Productos Biológicos/uso terapéutico , Productos Biológicos/farmacología , Productos Biológicos/química , Animales , Polifenoles/uso terapéutico , Polifenoles/química , Polifenoles/farmacología , Antiinflamatorios/uso terapéutico , Antiinflamatorios/farmacología , Antiinflamatorios/química
2.
Molecules ; 27(21)2022 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-36364203

RESUMEN

Fatigue seriously affects people's work efficiency and quality of life and has become a common health problem in modern societies around the world. The pathophysiology of fatigue is complex and not fully clear. To some degree, interactions between gut microbiota and host may be the cause of fatigue progression. Polyphenols such as tannin, tea polyphenols, curcumin, and soybean isoflavones relieve fatigue significantly. Studies have shown that the gut microbiota is able to convert these active compounds into more active metabolites through intestinal fermentation. However, the mechanism of anti-fatigue polyphenols is currently mainly analyzed from the perspective of antioxidant and anti-inflammatory effects, and changes in gut microbiota are rarely considered. This review focuses on gut microecology and systematically summarizes the latest theoretical and research findings on the interaction of gut microbiota, fatigue, and polyphenols. First, we outline the relationship between gut microbiota and fatigue, including changes in the gut microbiota during fatigue and how they interact with the host. Next, we describe the interactions between the gut microbiota and polyphenols in fatigue treatment (regulation of the gut microbiota by polyphenols and metabolism of polyphenols by the gut microbiota), and how the importance of potential active metabolites (such as urolithin) produced by the decomposition of polyphenols by gut microbiota is emerging. Based on the new perspective of gut microbiota, this review provides interesting insights into the mechanism of polyphenols in fatigue treatment and clarifies the potential of polyphenols as targets for anti-fatigue product development, aiming to provide a useful basis for further research and design.


Asunto(s)
Microbioma Gastrointestinal , Polifenoles , Humanos , Polifenoles/farmacología , Polifenoles/uso terapéutico , Polifenoles/metabolismo , Microbioma Gastrointestinal/fisiología , Calidad de Vida , Extractos Vegetales
3.
Eur J Nutr ; 60(7): 3525-3542, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33439332

RESUMEN

Phyllanthus emblica is a fruit widely consumed in subtropical areas, which is rich in polyphenols and other nutrients. There are increasing evidences that as a daily and nutritious fruit, it may have a positive role in controlling diabetic complications. According to the new study, its mechanisms include enhancing the functioning of insulin, reducing insulin resistance, activating the insulin-signaling pathway, protecting ß-cells, scavenging free radicals, alleviating inflammatory reactions, and reducing the accumulation of advanced glycation end products. Owing to its few side effects, and low price, it should be easily accepted by patients and has potential for preventing diabetes. Taken together, Phyllanthus emblica may be an ideal fruit for controlling diabetic complications. This review highlights the latest findings of the role of Phyllanthus emblica in anti-diabetes and its complications, especially clarifies the molecular mechanism of the chemical components related to this effect, and prospects some existing problems and future research directions.


Asunto(s)
Diabetes Mellitus Tipo 2 , Phyllanthus emblica , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Frutas , Humanos , Extractos Vegetales/uso terapéutico , Polifenoles
4.
Pharmacol Res ; 161: 105109, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32738494

RESUMEN

Protocatechuic acid is a natural phenolic acid, which widely exists in our daily diet and herbs. It is also one of the main metabolites of complex polyphenols, such as anthocyanins and proanthocyanins. In recent years, a large number of studies on the pharmacological activities of protocatechuic acid have emerged. Protocatechuic acid has a wide range of pharmacological activities including antioxidant, anti-inflammatory, neuroprotective, antibacterial, antiviral, anticancer, antiosteoporotic, analgesia, antiaging activties; protection from metabolic syndrome; and preservation of liver, kidneys, and reproductive functions. Pharmacokinetic studies showed that the absorption and elimination rate of protocatechuic acid are faster, with glucuronidation and sulfation being the major metabolic pathways. However, protocatechuic acid displays a dual-directional regulatory effect on some pharmacological activities. When the concentration is very high, it can inhibit cell proliferation and reduce survival rate. This review aims to comprehensively summarize the pharmacology, pharmacokinetics, and toxicity of protocatechuic acid with emphasis on its pharmacological activities discovered in recent 5 years, so as to provide more up-to-date and thorough information for the preclinical and clinical research of protocatechuic acid in the future. Moreover, it is hoped that the clinical application of protocatechuic acid can be broadened, giving full play to its characteristics of rich sources, low toxicity and wide pharmacological activites.


Asunto(s)
Dieta , Hidroxibenzoatos/farmacología , Extractos Vegetales/farmacología , Animales , Relación Dosis-Respuesta a Droga , Humanos , Hidroxibenzoatos/administración & dosificación , Hidroxibenzoatos/farmacocinética , Hidroxibenzoatos/toxicidad , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacocinética , Extractos Vegetales/toxicidad
5.
Pharmacol Res ; 155: 104738, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32151681

RESUMEN

Breast cancer remains the leading cause of cancer-related death among women worldwide, and its incidence is also increasing. High recurrence rate and metastasis rate are the key causes of poor prognosis and death. It is suggested that abnormal glycosylation plays an important role in the growth, invasion, metastasis and resistance to therapy of breast cancer cells. Meanwhile, it can be used as the biomarkers for the early detection and prognosis of breast cancer and the potential attractive targets for drug treatment. However, only a few attentions have been paid to the molecular mechanism of abnormal glycosylation in the epithelial-mesenchymal transition (EMT) of breast cancer cells and the related intervention of drugs. This manuscript thus investigated the relationship between abnormal glycosylation, the EMT, and breast cancer metastasis. Then, the process of abnormal glycosylation, the classification and their molecular regulatory mechanisms of breast cancer were analyzed in detail. Last, potential drugs are introduced in different categories, which are expected to reverse or intervene the abnormal glycosylation of breast cancer. This review is conducive to an in-depth understanding of the metastasis and drug resistance of breast cancer cells, which will provide new ideas for the clinical regulation of glycosylation and related drug treatments in breast cancer.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama , Glicosilación/efectos de los fármacos , Animales , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Humanos
6.
Pharmacol Res ; 148: 104409, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31446039

RESUMEN

It is a common phenomenon that people are in a sub-health condition and facing "unexplained fatigue", which seriously affects their health, work efficiency and quality of life. Meanwhile, fatigue is also a common symptom of many serious diseases such as HIV/AIDS, cancer, and schizophrenia. However, there are still no official recommendations for the treatment of various forms of fatigue. Some traditional natural medicines are often used as health care products, such as ginseng, Cordyceps militaris (L.ex Fr.Link) and Rhodiola rosea L., and these have been reported to have specific anti-fatigue effects with small toxic and side effects and rich pharmacological activities. It may be promising treatment strategy for sub-health. In this review, we first outline the generation of fatigue. Furthermore, we put emphasis on the anti-fatigue mechanism, bioactive components, and clinic trials of natural medicines, which will contribute to the development of potential anti-fatigue agents and open up novel treatments for sub-health.


Asunto(s)
Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Fatiga/tratamiento farmacológico , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Animales , Humanos , Medicina Tradicional/métodos , Fitoterapia/métodos , Calidad de Vida
7.
Molecules ; 24(17)2019 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-31450584

RESUMEN

For the treatment of diseases, especially chronic diseases, traditional natural drugs have more effective therapeutic advantages because of their multi-target and multi-channel characteristics. Among many traditional natural medicines, resins frankincense and myrrh have been proven to be effective in the treatment of inflammation and cancer. In the West, frankincense and myrrh have been used as incense in religious and cultural ceremonies since ancient times; in traditional Chinese and Ayurvedic medicine, they are used mainly for the treatment of chronic diseases. The main chemical constituents of frankincense and myrrh are terpenoids and essential oils. Their common pharmacological effects are anti-inflammatory and anticancer. More interestingly, in traditional Chinese medicine, frankincense and myrrh have been combined as drug pairs in the same prescription for thousands of years, and their combination has a better therapeutic effect on diseases than a single drug. After the combination of frankincense and myrrh forms a blend, a series of changes take place in their chemical composition, such as the increase or decrease of the main active ingredients, the disappearance of native chemical components, and the emergence of new chemical components. At the same time, the pharmacological effects of the combination seem magically powerful, such as synergistic anti-inflammation, synergistic anticancer, synergistic analgesic, synergistic antibacterial, synergistic blood-activation, and so on. In this review, we summarize the latest research on the main chemical constituents and pharmacological activities of these two natural resins, along with chemical and pharmacological studies on the combination of the two.


Asunto(s)
Olíbano/química , Resinas de Plantas/química , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Commiphora , Olíbano/farmacología , Humanos , Estructura Molecular , Fitoquímicos/química , Fitoquímicos/farmacología , Resinas de Plantas/farmacología
8.
Molecules ; 24(21)2019 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-31683690

RESUMEN

Gac fruit (Momordica cochinchinensis Spreng) is a popular tropical fruit in southeast Asia. What is amazing is that its seeds (Momordicae Semen) and arils are traditional herbs with anti-tumor activity, and have protected human health for more than 1000 years. In recent years, its anti-tumor activity has received extensive attention and research. This manuscript summarized the chemical composition of saponins, fatty acids, volatile constituents, proteins, peptides, and other components from Momordicae Semen (MSE). The effect and mechanism of MSE and its extract on breast cancer, gastric cancer, lung cancer, esophagus cancer, melanomas, and human cervical epithelial carcinoma were discussed. In addition, its antioxidant, anti-inflammatory, and other pharmacological effects were also analyzed. We hope that this review will provide new ideas for the treatment of cancer and other diseases, and become a reference for the further research into complementary and alternative medicine.


Asunto(s)
Antineoplásicos/farmacología , Frutas/química , Momordica/química , Clima Tropical , Animales , Antiinflamatorios/farmacología , Frutas/anatomía & histología , Humanos , Fitoquímicos/química
9.
J Vis Exp ; (194)2023 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-37125797

RESUMEN

The extraction intermediate of traditional Chinese medicine is the key intermediate in the preparation process, and its stability has an important impact on the effectiveness and quality of the final product. However, existing stability evaluation methods are often time-consuming and labor-intensive, requiring long-term observation and the operation of complex equipment (such as high-performance liquid chromatography), and it is difficult to obtain more physical information about the instability of the system. Therefore, there is an urgent need to establish a fast and accurate stability analysis technology for traditional Chinese medicine. Multiple light scattering is a cutting-edge analytical method that can accurately and rapidly evaluate the stability of traditional Chinese medicines in an environment-friendly manner without changing the nature or state of the sample or using organic reagents. In this work, using the precise scanning data of multiple light scattering, the present protocol rapidly acquired the variation curves for layer thickness, particle migration speed, and average particle size over time. This enabled the precise identification of the mechanism and crucial characteristics causing the system's instability in its early stages. Of note, the research period for the extraction process can be considerably shortened by the detailed quantification of the system stability, which also allows for a quick, accurate, and in-depth analysis of the effects of various extraction processes on the stability of Phyllanthus emblica L.


Asunto(s)
Phyllanthus emblica , Phyllanthus emblica/química , Medicina Tradicional China , Extractos Vegetales
10.
Biomed Pharmacother ; 139: 111561, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33848775

RESUMEN

Heparin is the earliest and most widely used anticoagulant and antithrombotic drug that is still used in a variety of clinical indications. Since it was discovered in 1916, after more than a century of repeated exploration, heparin has not been replaced by other drugs, but a great progress has been made in its basic research and clinical application. Besides anticoagulant and antithrombotic effects, heparin also has antitumor, anti-inflammatory, antiviral, and other pharmacological activities. It is widely used clinically in cardiovascular and cerebrovascular diseases, lung diseases, kidney diseases, cancer, etc., as the first anticoagulant medicine in COVID-19 exerts anticoagulant, anti-inflammatory and antiviral effects. At the same time, however, it also leads to a lot of adverse reactions, such as bleeding, thrombocytopenia, elevated transaminase, allergic reactions, and others. This article comprehensively reviews the modern research progress of heparin compounds; discusses the structure, preparation, and adverse reactions of heparin; emphasizes the pharmacological activity and clinical application of heparin; reveals the possible mechanism of the therapeutic effect of heparin in related clinical applications; provides evidence support for the clinical application of heparin; and hints on the significance of exploring the wider application fields of heparin.


Asunto(s)
Anticoagulantes/farmacología , Anticoagulantes/uso terapéutico , Medicamentos Esenciales , Fibrinolíticos/farmacología , Fibrinolíticos/uso terapéutico , Heparina/farmacología , Heparina/uso terapéutico , Animales , Enfermedades Cardiovasculares/tratamiento farmacológico , Trastornos Cerebrovasculares/tratamiento farmacológico , Humanos , Enfermedades Renales/tratamiento farmacológico , Lesión Pulmonar/tratamiento farmacológico , Tratamiento Farmacológico de COVID-19
11.
J Ethnopharmacol ; 265: 113326, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32877718

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Migraines have become a major threat to human health, as they significantly affect human health and quality of life due to a high prevalence rate, attack rate and pain intensity. Aromatherapy, with its comfortable and pleasant natural characteristics and rapid and efficient characteristics, is widely favored by patients in the folk. Chinese folk also have the application history and related records of aromatic plants in the treatment of migraine. AIM OF THE STUDY: This study was conducted to review the pathogenesis of migraine, the application of plant essential oils in the treatment of migraine, and further explore the material basis and mechanism of action of plant essential oils against migraine. MATERIALS AND METHODS: Search the electronic literature of essential oils with anti-migraine effect in Google Scholar, PubMed and China National Knowledge Infrastructure, and further search the research situation of the monomer components of essential oils in migraine, inflammation, pain and other aspects. RESULTS: studies show that there are 10 types of plant essential oils that could relieve migraine symptoms, and that 16 monomers may play a role in migraine treatment by effectively inhibiting neurogenic inflammation, hyperalgesia and balancing vasorelaxation. CONCLUSION: Aromatic plant essential oils can relieve migraine effectively, these findings can be used as an important part of the development of anti-migraine drugs.


Asunto(s)
Aromaterapia/métodos , Trastornos Migrañosos/terapia , Aceites Volátiles/administración & dosificación , Animales , Humanos , Trastornos Migrañosos/fisiopatología , Aceites Volátiles/farmacología , Aceites de Plantas/administración & dosificación , Aceites de Plantas/farmacología , Calidad de Vida
12.
Front Pharmacol ; 12: 583279, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33828481

RESUMEN

The coronavirus disease, 2019 (COVID-19), has spread rapidly around the world and become a major public health problem facing the world. Traditional Chinese medicine (TCM) has been fully committed to treat COVID-19 in China. It improved the clinical symptoms of patients and reduced the mortality rate. In light of the fever was identified as one of leading clinical features of COVID-19, this paper will first analyze the material basis of fever, including pyrogenic cytokines and a variety of the mediators of fever. Then the humoral and neural pathways of fever signal transmission will be described. The scattered evidences about fever recorded in recent years are connected in series. On this basis, the understanding of fever is further deepened from the aspects of pathology and physiology. Finally, combining with the chemical composition and pharmacological action of available TCM, we analyzed the mechanisms of TCMs to play the antipyretic effect through multiple ways. So as to further provide the basis for the research of antipyretic compound preparations of TCMs and explore the potential medicines for the prevention and treatment of COVID-19.

13.
Front Pharmacol ; 12: 664607, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34290606

RESUMEN

Background: Triphala is a traditional polyherbal formula used in Indian Ayurvedic and Chinese Tibetan medicine. A wide range of biological activities have been attributed to Triphala, but the impact of various extraction methods on efficacy has not been determined. Purpose: The study aimed to evaluate Triphala extracts obtained by various methods for their hepatoprotective effects and molecular mechanisms in a mouse model of carbon tetrachloride (CCl4)-induced liver injury. Methods: HPLC fingerprinting was used to characterize the chemical characteristics of Triphala extracts obtained by (a) 0.5 h ultrasonication, (b) 2 h reflux, and (c) 4 h reflux. Hepatoprotective efficacy was evaluated in a mouse model of CCl4-induced liver damage. Serum levels of alanine transaminase (ALT) and aspartate aminotransferase (AST) were measured, as well as the liver antioxidant and inflammatory markers malondialdehyde superoxide dismutase glutathione peroxidase (GSH-Px), TNF-α, and IL-6. Gene and protein expression of Nrf-2 signaling components Nrf-2, heme oxygenase (HO-1), and NADPH Quinone oxidoreductase (NQO-1) in liver tissue were evaluated by real-time PCR and western blotting. Results: Chemical analysis showed a clear difference in content between extracts produced by ultrasonic and reflux methods. The pharmacological analysis showed that all three Triphala extracts reduced ALT, AST, MDA, TNF-α, and IL-6 levels and increased SOD and GSH-Px. Triphala extracts also induced transcript and protein expression of Nrf-2, HO-1, and NQO-1. Conclusion: Triphala extract prevents CCl4-induced acute liver injury. The ultrasonic extract of Triphala was most effective, suggesting that hepatoprotection may be related to the larger tannins via activation of Nrf-2 signaling.

14.
Front Pharmacol ; 12: 744035, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34916933

RESUMEN

Background: Zanthoxylum schinifolium is a common herbal medicine in Southwest China. It is also a condiment commonly used in many families. In Chinese folk medicine, Z. schinifolium is considered to have the effect of relieving migraine, but there is no modern evidence on its anti-migraine mechanism. Objective: The aim of this study was to investigate the chemical constituents of the supercritical carbon dioxide extracts of Z. schinifolium (CO2-ZSE) and its effects on migraine animals. Materials and Methods: Supercritical CO2 extraction technology was applied to extract the dried fruit of Z. schinifolium, and the chemical components were determined by gas chromatography-mass spectrometry (GC-MS). Two migraine animal models were established by subcutaneous injection of nitroglycerin (NTG) and reserpine, respectively, to further evaluate the therapeutic effect of CO2-ZSE and explore its mechanism. On the basis of the experimental results, the therapeutic effects of linalool in different dosages and different ways of administration on NTG-induced migraine rats have been further investigated. Results: About 125 peaks were detected in CO2-ZSE, and the relative content of linalool was 74.16%. CO2-ZSE decreased the number of head-scratching significantly and the levels of serum nitric oxide (NO), endothelin-1 (ET-1), calcitonin gene-related peptide (CGRP), interleukin-1ß (IL-1ß), nuclear factor kappa B (NF-κB) p65, and inhibitor of kappa B alpha (IκBα), and increased the level of 5-hydroxytryptamine (5-HT). Linalool has the potential to reduce the frequency of scratching the head and the expressions of NO, ET-1, and CGRP in NTG-induced migraine rats. Conclusion: CO2-ZSE has a definite therapeutic effect on migraine by affecting the expression of vasomotor factors and the inflammatory pathway. Linalool has been proven to be the main effective substance against migraine. These findings provide scientific basis for the development of effective and simple migraine therapy.

15.
Front Pharmacol ; 11: 556885, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33013395

RESUMEN

Novel coronavirus (COVID-19) pneumonia has become a major threat to worldwide public health, having rapidly spread to more than 180 countries and infecting over 1.6 billion people. Fever, cough, and fatigue are the most common initial symptoms of COVID-19, while some patients experience diarrhea rather than fever in the early stage. Many herbal medicine and Chinese patent medicine can significantly improve these symptoms, cure the patients experiencing a mild 22form of the illness, reduce the rate of transition from mild to severe disease, and reduce mortality. Therefore, this paper summarizes the physiopathological mechanisms of fever, cough, fatigue and diarrhea, and introduces Chinese herbal medicines (Ephedrae Herba, Gypsum Fibrosum, Glycyrrhizae Radix et Rhizoma, Asteris Radix et Rhizoma, Ginseng Radix et Rhizoma, Codonopsis Radix, Atractylodis Rhizoma, etc.) and Chinese patent medicines (Shuang-huang-lian, Ma-xing-gan-shi-tang, etc.) with their corresponding therapeutic effects. Emphasis was placed on their material basis, mechanism of action, and clinical research. Most of these medicines possess the pharmacological activities of anti-inflammatory, antioxidant, antiviral, and immunity-enhancement, and may be promising medicines for the treatment or adjuvant treatment of COVID-19 patients.

16.
Chin Med ; 15: 56, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32514289

RESUMEN

Quality consistency is one of the basic attributes of medicines, but it is also a difficult problem that natural medicines and their preparations must face. The complex chemical composition and comprehensive pharmacological action of natural medicines make it difficult to simply apply the commonly used evaluation methods in chemical drugs. It is thus urgent to explore the novel evaluation methods suitable for the characteristics of natural medicines. With the rapid development of analytical techniques and the deepening understanding of the quality of natural herbs, increasing numbers of researchers have proposed many new ideas and technologies. This review mainly focuses on the basic principles, technical characteristics and application examples of the chemical evaluation, biological evaluation methods and their combination in quality consistency evaluation of natural herbs. On the bases of chemical evaluation and clinical efficacy, new methods reflecting their pharmacodynamic mechanism and safety characteristics will be developed, and gradually towards accurate quality control, to achieve the goal of quality consistency. We hope that this manuscript can provide new ideas and technical references for the quality consistency of natural drugs and their preparations, thus better guarantee their clinical efficacy and safety, and better promote industrial development.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(6): 1209-12, 2008 Jun.
Artículo en Zh | MEDLINE | ID: mdl-18800689

RESUMEN

Wavelength conversion exploiting cascaded second harmonic and difference frequency generation (c(SHG/DFG)) in periodically polarized LiNbO3 (PPLN) waveguides was experimentally researched. While wavelength converter was pumped with a pulsed wave, the pump pulse can be used to carry the information and wavelength conversion occurs between the pump wave and converted wave, thus wavelength conversion transferring the information from the pump wave to the converted waves includes two processes of second order nonlinear reaction: the first wavelength conversion from pump wave to SH wave occurs with SHG process, and the second wavelength conversion from SH wave to converted wave occurs with DFG process. In the first process the group velocities mismatching (GVM) for pulses at different wavelengths due to material property load the temporal walk-off between pump pulse and SH pulse located in the 1.5 microm band and in the 0.8 microm band, respectively, so that SH pulse slowly propagates compared with pump pulse, and SH pulse width is broadened along propagation length. As a result, in the second process the converted DF pulse generates waveform distortion owing to the broadening of SH pulse in the first process. Both the waveform and the spectrum of converted pulse in our experimental results testify to the fact that SH pulse possesses a narrow spectral width, which is consistent with a long SH pulse, and the spectral width of converted DF pulse is compressed but its temporal width is broadened correspondingly. Therefore the influence of walk-off between pulses demonstrates that the pulsed pumping wavelength conversion is disadvantageous to the transparence of the data format. However, pulsed pumping wavelength conversion also presents great potential that can be applied in future optical networks. Tunable wavelength conversion can be easily implemented by changing the wavelength of control CW, and single-to-multiple channel wavelength conversion can be realized by increasing the number of the CW lasing pump channels. This is very important and it enhances the flexibility in the management of the multi-channel WDM network. Finally, a tunable and single-to-dual channel wavelength converter based on the scheme of pulsed pumping wavelength conversion achieved by our experiment setup, and two channel converted pulses simultaneously replicate the bit rate carried on pump pulses. It is pointed out that the quality such the signal-to-noise ratio of converted pulse is affected by spectral width of control CW.

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