976†nm and 808†nm dual-GSA-wavelength pumped 3 µm erbium-doped solid-state laser.

A dual-wavelength pumping scheme at 976 nm and 808 nm is proposed to improve the performance of 3 µm Er:YAP laser. 976 nm and 808 nm correspond to the ground state absorption processes of 4I15/2→I11/2 and 4I15/2→I9/2, respectively. The experimental results indicate that the introduction of 808 nm pumping not only increases the total inversion population, but also can adjust the population distribution among the sublevels in the upper and lower manifold, thus supporting higher output power and multiple wavelengths emissions. Under the single-wavelength pumping, the maximum output powers of 1.192 W and 0.223 W are obtained for 976 nm and 808 nm pumping, respectively. With regard to the 976/808 nm dual-wavelength pumping, the achievable maximum output power is 1.398 W, increased by 17.3% compared to the case of single-wavelength pumping at 976 nm. The dual-wavelength pumped Er:YAP laser can also operate in a state of multi-wavelength emissions at 2.79 µm, 2.82 µm and 2.92 µm with different dual-wavelength pump power combinations. Considering the broadband absorption characteristics of ground state absorption and the convenience of obtaining near-infrared laser diodes pumping sources, the proposed dual-wavelength pump scheme shows great potential to realize high-power, high-efficiency 3 µm erbium-doped solid-state lasers with better cost-effectiveness and more compact structure.

Chinese herbal medicines in the prevention and treatment of chemotherapy-induced nausea and vomiting.

PURPOSE OF REVIEW: Chemotherapy-induced nausea and vomiting (CINV) critically impact on cancer patients' quality of life, causing various complications, and increasing the risk of chemotherapeutic failure. Current treatments addressing CINV are reasonably costly and have many side effects. Chinese herbal medicines (CHMs) have been widely used in treating CINV in China. Clinical trials and modern experimental studies on CINV using CHMs are reviewed for clues that may help us to better prevent and treat CINV with CHMs, and develop safe and effective treatments. RECENT FINDINGS: Since 1985, 92 clinical trials on CINV were identified, which comprised of 3778 patients with different cancer types, chemotherapy regimens, prescriptions, treatment durations, and combinations with Western medicines. The most frequently used herbs are Pinellia Rhizoma, Glycyrrhizae Radix et Rhizoma, Poria, and Atractylodis Macrocephalae Rhizoma, aiming to regulate the flow of Qi and remove phlegm and dampness residing in the stomach and spleen. Although all of the reported trials are randomized open trials, the curative effects range from 55.81 to 100%. SUMMARY: CHMs seem effective in the prevention and treatment of CINV based on the clinical trials and some animal experiments, although the scientific validity of many clinical studies remain to be confirmed as many of them were inadequately designed. Further well designed clinical trials and more preclinical studies with reliable markers are required to confirm the usefulness of CHMs as complementary medicines for treating CINV and to use CHMs as rational prescriptions rather than based only on empirical knowledge.

Steamed root of Rehmannia glutinosa Libosch (Plantaginaceae) alleviates methotrexate-induced intestinal mucositis in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Intestinal mucositis induced by chemotherapy is a severe clinical problem in cancer patients that currently lack effective interventions. In traditional Chinese medicine, chemotherapeutic toxicity is diagnosed as Qi and Yin deficiency, and steamed rehmannia root (SRR) is frequently prescribed to these patients. Whether SRR can prevent the adverse effects remains to be confirmed experimentally. The present study used a rat model to investigate potential efficacy and action mechanisms of SRR in attenuating the adverse effects caused by chemotherapy. MATERIALS AND METHODS: Intraperitoneal injection of a single dose of anti-metabolite methotrexate (MTX, 25mg/kg) was given to adult Wistar rats, which also received oral gavage of water or SRR (1.08g/kg twice daily 3 days before and 4 days after MTX treatment), or calcium folinate (CF, a clinically used MTX antidote as a comparison, at 1mg/kg twice daily 36h after MTX treatment), or SRR and CF in combination. Animals were sacrificed 4 days after MTX treatment. Complete blood cell counting was carried out. Jejunum was analyzed histologically for mucosal damage, immunohistochemically for proliferating cell nuclear antigen (PCNA), and biochemically for thiobarbituric acid reactive substances (TBARS) and reduced glutathione (GSH), as well as for tumor necrosis factor alpha (TNF-α). RESULTS: MTX treatment led to weight loss, leucopenia, polycythemia, increase in large thrombocyte ratio, intestinal villus atrophy, crypt loss and reduction in PCNA positive crypt cells, increases in mucosal TBARS and TNF-α and decrease in GSH. All these alterations were inhibited by SRR administration except leucopenia, and the effects of CF or CF plus SRR supplementation were found to be inferior to those of SRR. CONCLUSIONS: SRR can alleviate MTX-induced gut mucositis, which may be achieved by inhibiting MTX-induced oxidative stress and inflammatory response. These findings support the application of SRR in chemotherapy but not the combined application of SRR and CF.