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1.
Bioconjug Chem ; 35(3): 400-411, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38366969

ABSTRACT

Photodynamic therapy (PDT) is a cancer treatment strategy that utilizes photosensitizers to convert oxygen within tumors into reactive singlet oxygen (1O2) to lyse tumor cells. Nevertheless, pre-existing tumor hypoxia and oxygen consumption during PDT can lead to an insufficient oxygen supply, potentially reducing the photodynamic efficacy. In response to this issue, we have devised a pH-responsive amphiphilic triblock fluorinated polymer (PDP) using copper-mediated RDRP. This polymer, composed of poly(ethylene glycol) methyl ether acrylate, 2-(diethylamino)ethyl methacrylate, and (perfluorooctyl)ethyl acrylate, self-assembles in an aqueous environment. Oxygen, chlorine e6 (Ce6), and doxorubicin (DOX) can be codelivered efficiently by PDP. The incorporation of perfluorocarbon into the formulation enhances the oxygen-carrying capacity of PDP, consequently extending the lifetime of 1O2. This increased lifetime, in turn, amplifies the PDT effect and escalates the cellular cytotoxicity. Compared with PDT alone, PDP@Ce6-DOX-O2 NPs demonstrated significant inhibition of tumor growth. This study proposes a novel strategy for enhancing the efficacy of PDT.


Subject(s)
Nanoparticles , Photochemotherapy , Porphyrins , Humans , Fluorocarbon Polymers , Oxygen , Cell Line, Tumor , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Hypoxia/drug therapy , Hydrogen-Ion Concentration
2.
Huan Jing Ke Xue ; 38(5): 2102-2110, 2017 May 08.
Article in Chinese | MEDLINE | ID: mdl-29965119

ABSTRACT

Soil respiration is an important process for carbon emission. A field study was conducted with four treatments including T (traditional tillage+straw mulching level 0 kg·hm-2), R (ridge tillage+straw mulching level 0 kg·hm-2), RS1 (ridge tillage+straw mulching level 3750 kg·hm-2), and RS2 (ridge tillage+straw mulching level 7500 kg·hm-2), so as to probe the effects of ridge tillage and straw mulching amount on soil respiration and soil organic carbon(SOC) and the relationships of soil respiration rate with soil temperature and water content (SWC) during the growth period of fava bean in the triple intercropping system of fava bean/maize/sweat pomato in dryland region of southwest China known as the purple hilly region. The changes of soil respiration rate were in accordance with crop growing, being firstly increased and then decreased during the whole growth period of fava bean, and there were significant differences in soil respiration rate among different treatments, which could be ranked as RS2[3.365 g·(m2·d)-1] > RS1[2.935 g·(m2·d)-1] > T[2.683 g·(m2·d)-1] > R[2.263 g·(m2·d)-1]. Ridge tillage reduced soil respiration in fava bean farmland, whereas straw mulching treatment increased it, whose variation trend was in accordance with that of straw mulching levels. There was a significant exponential relationship between soil respiration and soil temperature at 5 cm and 10 cm depth, and the exponential model at 10 cm produced better fitness than that at 5 cm. The temperature sensitivity (Q10) at 10 cm could be ranked as RS2 > RS1 > R > T, being 1.751,1.665,1.616, and 1.35, respectively. The combined exponential model indicated that soil temperature and water content (SWC) could jointly explain 68%(R), 79%(RS1) and 76%(RS2) of variation in soil respiration. This study results suggested that ridge tillage and straw mulching significantly increased SOC of 0-5 cm, 5-10 cm, 10-20 cm and 20-30 cm soil layers, and the increase of SOC was in accordance with that of straw mulching levels. The SOC was significantly increased in 5-10 cm and 10-20 cm soil layers, which could be ranked as RS2 > RS1 > R > T, and the increases in SOC at 5-10 cm were especially notable. The weighted average of particulate organic carbon (POC) at 0-30 cm was significantly increased, but the proportion of POC in SOC did not show significant influence.


Subject(s)
Agriculture , Carbon/chemistry , Soil/chemistry , China , Farms , Triticum , Vicia faba
3.
Huan Jing Ke Xue ; 37(3): 1114-20, 2016 Mar 15.
Article in Chinese | MEDLINE | ID: mdl-27337908

ABSTRACT

Under the background of global warming, the farmland soil respiration has become the main way of agricultural carbon emissions. And green manure has great potential to curb greenhouse gas emissions and achieve energy conservation and emissions reduction. However, in purple soil region of Southwest, China, soil respiration under green manure remains unclear, especially in the winter and intercropping. Through the green manure ( Chinese milk vetch) intercropping with rape, therefore, we compared the effects of rape rhizosphere under straw mulching. The soil organic carbon and soil respiration were examined. The results showed, compared with straw mulching, root separation was the major influencing factors of soil organic carbon on rape rhizosphere. Soil organic carbon was significantly decreased by root interaction. In addition, straw mulching promoted while green manure intercropping inhibited the soil respiration. Soil respiration presented the general characteristics of fall-rise-fall due to the strong influence of rape growth period. Therefore, it showed a cubic curve relationship with soil temperature.


Subject(s)
Agriculture/methods , Brassica rapa/growth & development , Carbon/analysis , Manure , Rhizosphere , Soil/chemistry , China , Environmental Monitoring , Seasons , Temperature
4.
Article in English | MEDLINE | ID: mdl-21375929

ABSTRACT

OBJECTIVE: To elucidate the growth and development of patients with Cushing's syndrome (CS) in adolescence. METHODS: We analyzed the clinical data of 19 patients aged under 18 with CS. We divided the patients into two groups according to the height at diagnosis. The patients under the 3rd percentile were in the short stature group (n=12), and the others in the non-short stature group (n=7). The intergroup differences in disease course, age of onset, and 24-hour urinary free cortisol were analyzed. RESULTS: The median age at diagnosis was 13 years. The median disease course was 0.9 years. All those patients presented with typical clinical characteristics of CS. Twelve cases (63.2%) were in short stature group. The disease course of the short stature group was found significantly longer than that of the non-short stature group [(2.7∓1.7) years vs. (0.8∓0.6) years, P=0.013], but no significant difference was found in the age of onset (P=0.530) or 24-hour urinary free cortisol (P=0.919) between the two groups. CONCLUSIONS: The data suggest that short stature is common in adolescent CS patients. The growth delay may be correlated to the disease course of CS.


Subject(s)
Adolescent Development/physiology , Cushing Syndrome/physiopathology , Adolescent , Child , Female , Humans , Male , Retrospective Studies
5.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-285042

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the CYP17A1 gene mutations in a Chinese 46,XX patient with partial combined 17 alpha-hydroxylase/17,20-lyase deficiency.</p><p><b>METHODS</b>Clinical data were retrospectively analyzed. The genomic DNA of the patient and her parents was isolated from whole blood. Seven pairs of primers were used to amplify eight exons and exon-intron boundaries of the CYP17A1 gene. The amplified PCR products were purified by agarose gel and then directly sequenced. In order to confirm the DNA sequences of different alleles, some fragments were inserted into pMD 18-T vector and then subclone sequenced. Sequencing results were compared to the established human CYP17A1 sequence.</p><p><b>RESULTS</b>The patient was new compound heterozygous of 5994-5995 delAT/7541 C>T. The mutation 5994-5995 del AT, causing amino acid I259H, 274X, was proposed to result early truncated protein which was lack of the activity center site of P450C17, whereas missense mutation 7541 C>T causing A398V did not lie in the active site of the enzyme according to the computer model of human P450C17. The 46, XX case had irregular menstruation and slightly hypertension and hypokalemia. The ACTH stimulating test as well as the result of the sex hormones suggested that there was partial 17 alpha-hydroxylase/17, 20-lyase enzyme activities in the adrenal and sexual gland. We speculate that A398V might conserve partial of the enzyme's activities. The genotype was coincident with phenotype.</p><p><b>CONCLUSION</b>More study should be done to have better understanding of the function of the mutated P450C17 enzymes.</p>


Subject(s)
Female , Humans , Young Adult , Adrenal Hyperplasia, Congenital , Genetics , Base Sequence , DNA Mutational Analysis , Exons , Genetics , Heterozygote , Introns , Genetics , Mutation , Polymerase Chain Reaction , Steroid 17-alpha-Hydroxylase , Genetics , Metabolism
6.
Article in English | WPRIM (Western Pacific) | ID: wpr-263837

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the CYP17A1 gene mutations in Chinese patients with 17 alpha-hydroxylase/17, 20-lyase deficiency.</p><p><b>METHODS</b>Clinical data were retrospectively analyzed. The CYP17A1 gene mutations were detected in 5 cases with 17 alpha-hydroxylase/17, 20-lyase deficiency and their relatives. The genomic DNA of the patients was isolated from whole blood. Seven pairs of primers were used to amplify eight exons and exon-intron boundaries of the CYP17A1 gene. The amplified PCR products were purified by agarose gel and then directly sequenced. In order to confirm the DNA sequences of different alleles, some fragments were inserted into pMD 18-T vector and then sequenced. Sequencing results were compared to the established human CYP17A1 sequence.</p><p><b>RESULTS</b>Briefly, we found 2 kinds of compound mutations, of which were: (1) 6436-6438(TAC-->AA), causing amino acid Y329K, 418X; (2) 6531-6532(GC-->A), causing amino acid L361F, 418X. Among the five cases, four were homozygous for 6436-6438(TAC-->AA), whereas one was compound heterozygous for 6436-6438(TAC-->AA)/6531-6532(GC-->A). The clinical characteristics of 5 cases were all completely combined defects of 17 alpha-hydroxylase/17, 20-lyase, and they all carried two alleles of CYP17A1 gene mutations that all shifted the reading frame and resulted in truncated protein which lack of the activity center site of P450C17, of which corresponding with their clinical feature.</p><p><b>CONCLUSION</b>Nine alleles have the mutation of 6436-6438(TAC-->AA), accounting for 90% of total alleles (9/10). That suggests this kind of mutation may have racial specificity. More study should be done to have better understanding of the function of the truncated P450C17 enzymes.</p>


Subject(s)
Adolescent , Humans , Male , Young Adult , Adrenal Hyperplasia, Congenital , Genetics , Alleles , Asian People , Genetics , Base Sequence , DNA , DNA Mutational Analysis , DNA Primers , Exons , Genetics , Molecular Sequence Data , Mutation , Point Mutation , Polymerase Chain Reaction , Sexual Infantilism , Genetics , Steroid 17-alpha-Hydroxylase , Genetics , Metabolism
7.
Chinese Journal of Surgery ; (12): 583-586, 2004.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-299897

ABSTRACT

<p><b>OBJECTIVE</b>To investigate and discuss the diagnosis and treatment of ectopic ACTH syndrome.</p><p><b>METHODS</b>Clinical data of 32 cases of ectopic ACTH syndrome, recruited from January 1990 to April 2003 in our hospital, was analyzed.</p><p><b>RESULTS</b>All of the 32 cases presented with clinical and biochemical evidences of Cushing's syndrome. Ten cases were definitively diagnosed as ectopic ACTH syndrome by finding ectopic tumors; 4 cases were highly suspected as ectopic ACTH by blood sampling from femoral vein and infra-petrosal vein and 18 cases were suspected as ectopic ACTH by imaging examinations. Fifteen cases (47%), without identified source of ectopic hormone, were treated with bilateral or unilateral total adrenalectomy, with 1-year survival rate of 60%. Seven cases (22%), with possible source of ectopic hormone, underwent no intervention, with 1-year survival rate of 0. Ten cases underwent radical resection of tumor, 6 of which were bronchial carcinoids and 4 of which were thymic carcinoids, with 1-year survival rate of 60%.</p><p><b>CONCLUSION</b>It is very difficult to localize the tumor of ectopic ACTH syndrome patients. Bilateral adrenalectomy followed by hormonal replacement is effective for most of the patients without identifying source of ectopic hormone.</p>


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , ACTH Syndrome, Ectopic , Diagnosis , Mortality , Therapeutics , Adrenalectomy , Methods , Combined Modality Therapy , Follow-Up Studies , Survival Rate
12.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-278103

ABSTRACT

<p><b>OBJECTIVE</b>To improve the diagnosis and treatment of adrenal incidentaloma (AI).</p><p><b>METHODS</b>Retrospective analysis of 103 AI patients in PUMC Hospital from 1994 to 2002.</p><p><b>RESULTS</b>Of the 103 cases (43 men and 60 women), most patients were 40-60 years old. Eighty-five cases (82.5%) were benign masses, of which 36 (35.0%) were non-functional adrenal cortical adenoma, and 12 (11.7%) were pheochromocytoma, 1 (1%) was Cushing's syndrome and 1 for aldosteronomas. Three cases did not show clinical feature and the diagnosis of pheochromocytoma were based on 131I-MIBG. Among 18 (17.5%) malignant tumors, adrenal carcinomas account for the majority (8 cases, 7.8%). Patients with malignant masses were significantly younger than patients with adenomas (P < 0.05), and the adenomas were significantly smaller than malignancy (P < 0.001). A cut-off at 4.0 cm of tumor mass size was set for differentiating benign and malignant tumors.</p><p><b>CONCLUSIONS</b>During the diagnosis of AI, it's essential to evaluate hormonal activity and assess for the risk of malignancy. If the mass size is 4 cm or larger, the risk of malignancy increases. More attention should be paid to subclinical hyperfunctional state.</p>


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Adenoma , Diagnosis , Adrenal Cortex Neoplasms , Diagnosis , Carcinoma , Diagnosis , Cushing Syndrome , Diagnosis , Diagnosis, Differential , Pheochromocytoma , Diagnosis , Retrospective Studies
13.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-683399

ABSTRACT

Objectives To summarize the characteristics,differential diagnosis and management of incomplete 17 alpha-hydroxylase/17,20-1yase deficiency(17 OHD)of Chinese patients.Methods Six cases of incomplete 17 OHD from Peking Union Medical College Hospital were studied retrospectively through analyzing their clinical data,and the molecular pathogenic mechanism was discussed after literature review.Results Four cases of 46,XX incomplete 17 OHD were reported.The clinical characteristics included female phenotype,various degrees of breast development and absent or sparse axillary/pubic hair, oligomenorrhea or secondary amenorrhea,recurrent luteinized ovarian cysts,hypogonadism with persistent hyperprogesteronemia or high serum 17 alpha-hydroxyprogesterone level,with or without hypokalemic hypertension.There were also 2 cases of 46,XY incomplete 17 OHD,in which ambiguous genitalia were present besides hypokalemic hypertension.Conclusions Incomplete 17 OHD is a very rare form of congenital enzymatic deficiencies of steroid synthesis,which should be included in the differential diagnosis when there are menstrual disorders,sexual infantilism,recurrent ovarian cysts or ambiguous genitalia.Under such circumstances,hyperprogesteronemia offers a valuable clue for further investigation.

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