1
|
The environmental and socioeconomic effects of tuberculosis patients in the southwest of China: a population-based study. Public Health 2024; 227:131-140. [PMID: 38219290 DOI: 10.1016/j.puhe.2023.10.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 09/14/2023] [Accepted: 10/26/2023] [Indexed: 01/16/2024]
Abstract
OBJECTIVE The objective of this study was to assess the incidence of tuberculosis (TB) and find the risk factors of TB patients with a high burden of TB in socioeconomic level, the high level of TB incidence and the great changes of economic and social factors, explore the possible factors, construct scientific and robust prediction model, and analyse whether the task of stopping TB can be accomplished by the expected global deadline. STUDY DESIGN This was an ecological study. METHODS Descriptive analysis, spatial and space-time scan, correlation analysis, and regression analysis were carried out, based on cases of TB in Sichuan Province and ecological data from 2006 to 2017, to explore the characters of TB and ecological factors, using the transfer function-noise model to forecast the trend of TB until 2035. RESULTS Factors affecting the incidence of TB, increasing per capita green area, reporting status of TB among Tibetans and Yi minorities, comprehensive treatment management, total cost of TB per capita for urban residents, proportion of males with high school education, 20 to 20 h of 24-h accumulated precipitation, reducing HIV at the same time as AIDS deaths, the increase in the proportion of males in junior high school education, and the increase in the number of registered TB cases can reduce the incidence of TB. CONCLUSIONS There was concentration mainly on enhanced control of the environment and society measures, helpful in guiding government planning to control TB. Reinforcement is required to reduce the TB of population aged 15-24 and aged 25-64 in socioeconomic level by 2035.
Collapse
|
2
|
[Pelvic exenteration for late complications of radiation-induced pelvic injury: a preliminary study]. ZHONGHUA WEI CHANG WAI KE ZA ZHI = CHINESE JOURNAL OF GASTROINTESTINAL SURGERY 2023; 26:940-946. [PMID: 37849264 DOI: 10.3760/cma.j.cn441530-20230816-00053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 10/19/2023]
Abstract
Objective: To investigate the safety and efficacy of total pelvic exenteration (TPE) for treating late complications of radiation-induced pelvic injury. Methods: This was a descriptive case series study. The inclusion criteria were as follows: (1) confirmed radiation-induced pelvic injury after radiotherapy for pelvic malignancies; (2) late complications of radiation-induced pelvic injury, such as bleeding, perforation, fistula, and obstruction, involving multiple pelvic organs; (3) TPE recommended by a multidisciplinary team; (4) patient in good preoperative condition and considered fit enough to tolerate TPE; and (5) patient extremely willing to undergo the procedure and accept the associated risks. The exclusion criteria were as follows: (1) preoperative or intraoperative diagnosis of tumor recurrence or metastasis; (2) had only undergone diversion or bypass surgery after laparoscopic exploration; and (3) incomplete medical records. Clinical and follow-up data of patients who had undergone TPE for late complications of radiation-induced pelvic injury between March 2020 and September 2022 at the Sixth Affiliated Hospital of Sun Yat-sen University were analyzed. Perioperative recovery, postoperative complications, perioperative deaths, and quality of life 1 year postoperatively were recorded. Results: The study cohort comprised 14 women, nine of whom had recto-vagino-vesical fistulas, two vesicovaginal fistulas, one ileo-vesical fistula and rectal necrosis, one ileo-vesical and rectovaginal fistulas, and one rectal ulcer and bilateral ureteral stenosis. The mean duration of surgery was 592.1±167.6 minutes and the median blood loss 550 (100-6000) mL. Ten patients underwent intestinal reconstruction, and four the Hartmann procedure. Ten patients underwent urinary reconstruction using Bricker's procedure and 7 underwent pelvic floor reconstruction. The mean postoperative hospital stay was 23.6±14.9 days. Seven patients (7/14) had serious postoperative complications (Clavien-Dindo IIIa to IVb), including surgical site infections in eight, abdominopelvic abscesses in five, pulmonary infections in five, intestinal obstruction in four, and urinary leakage in two. Empty pelvis syndrome (EPS) was diagnosed in five patients, none of whom had undergone pelvic floor reconstruction. Five of the seven patients who had not undergone pelvic floor reconstruction developed EPS, compared with none of those who had undergone pelvic floor reconstruction. One patient with EPS underwent reoperation because of a pelvic abscess, pelvic hemorrhage, and intestinal obstruction. There were no perioperative deaths. During 18.9±10.1 months of follow-up, three patients died, two of renal failure, which was a preoperative comorbidity, and one of COVID-19. The remaining patients had gradual and significant relief of symptoms during follow-up. QLQ-C30 assessment of postoperative quality of life showed gradual improvement in all functional domains and general health at 1, 3, and 6 months postoperatively (all P<0.05). Conclusions: TPE is a feasible procedure for treating late complications of radiation-induced pelvic injury combined with complex pelvic fistulas. TPE is effective in alleviating symptoms and improving quality of life. However, the indications for this procedure should be strictly controlled and the surgery carried out only by experienced surgeons.
Collapse
|
3
|
Characteristics of flight delays during solar flares. Sci Rep 2023; 13:6101. [PMID: 37055539 PMCID: PMC10102245 DOI: 10.1038/s41598-023-33306-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 04/10/2023] [Indexed: 04/15/2023] Open
Abstract
Solar flares are one of the severest solar activities that have important effects on near-Earth space. Previous studies have shown that flight arrival delays increase as a result of solar flares, but the intrinsic mechanism behind this relationship is still unknown. In this study, we conducted a comprehensive analysis of flight departure delays during 57 solar X-ray events by using a huge amount of flight data (~ 5 × 106 records) gathered over a 5-year period. It is found that the average flight departure delay time during solar X-ray events increased by 20.68% (7.67 min) compared to quiet periods. Our analysis also revealed apparent time and latitude dependencies, with flight delays being more serious on the dayside than on the nightside and longer (shorter) delays tending to occur in lower (higher) latitude airports during solar X-ray events. Furthermore, our results suggest that the intensity of solar flares (soft X-ray flux) and the Solar Zenith Angle directly modulate flight departure delay time and delay rate. These results indicate that communication interferences caused by solar flares directly affect flight departure delays. This work expands our conventional understanding of the impacts of solar flares on human society and provides new insights for preventing or coping with flight delays.
Collapse
|
4
|
[Clincal practice of pelvic exenteration for late complications of pelvic radiation injury]. ZHONGHUA WEI CHANG WAI KE ZA ZHI = CHINESE JOURNAL OF GASTROINTESTINAL SURGERY 2023; 26:235-240. [PMID: 36925123 DOI: 10.3760/cma.j.cn441530-20221206-00510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
Pelvic radiation injury can potentially involve multiple pelvic organs, and due to its progressive and irreversible nature, its late stage can be complicated by fistulas, perforations, obstructions and other complications involved multiple pelvic organs, which seriously affect the long-term survival and the quality of life of patients. As a multidisciplinary surgical approach, pelvic exenteration has potential application in the treatment of late complications of pelvic radiation injury by completely removing the irradiated lesion, relieving symptoms and avoiding recurrence of symptoms. In clinical practice, we should advocate the concept of "pelvic radiation injury", emphasize multidisciplinary collaboration, fully evaluate the overall status of patients, primary tumor and pelvic radiation injury. We should follow the principles of "damage-control" and "extended resection", and follow the principle of enhanced recovery after surgery to achieve the goal of ensuring the surgical safety, relieving patients' symptoms and improving patients' quality of life and long-term survival.
Collapse
|
5
|
Identifying research priorities with children, youth, and families: A scoping review. J Child Health Care 2023:13674935231151748. [PMID: 36647285 DOI: 10.1177/13674935231151748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Increased patient advocacy has resulted in a shift toward more active patient engagement in the research. A scoping review was conducted to explore the literature on healthcare research priority settings wherein children, youths, or their families were involved in the priority-setting process. Six databases including MEDLINE, CINAHL, PsycINFO, Embase, Web of Science, and Global Health and the James Lind Alliance website were searched up until September 2019. All primary studies involving children (<18 years of age) or families in developing research priorities in health care were included. All retrieved references were uploaded into Covidence, and two independent reviewers screened the search results. Descriptive thematic analysis was used to identify common themes. A total of 30 studies with 4247 participants were included. Less than half of the participants (n = 1237, (33%) were pediatric patients and their families. A total of 455 research priorities were identified. Three common themes emerged: (i) quality of care delivery, (ii) self-efficacy in health behaviors, and (iii) community engagement in care. This scoping review revealed priority research health topics from the perspectives of children, youths, or their families. The findings may be used as a foundation for future research to improve the health outcomes of children, youths, or their families according to their identified priorities.
Collapse
|
6
|
[Bowel preparation before elective surgery for colorectal cancer]. ZHONGHUA WEI CHANG WAI KE ZA ZHI = CHINESE JOURNAL OF GASTROINTESTINAL SURGERY 2022; 25:645-647. [PMID: 35844130 DOI: 10.3760/cma.j.cn441530-20220221-00056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
For elective surgery of colorectal cancer, current evidence supports preoperative mechanical bowel preparation combined with oral antibiotics. Meanwhile, for patients with varied degrees of intestinal stenosis, individualized protocol is required to avoid adverse events. We hereby summarize recent high-quality evidences and updates of guidelines and consensus, and recommend stratified bowel preparation based on the clinical practice of our institute as follows. (1) For patients with unimpaired oral intake, whose tumor can be passed by colonoscopy, mechanical bowel preparation and oral antibiotics are given. (2) For patients without symptoms of bowel obstruction but with impaired oral intake or incomplete colonoscopy due to tumor-related stenosis, small-dosage laxative is given for several days before surgery, and oral antibiotics the day before surgery. (3) For patients with bowel obstruction, mechanical bowel preparation or enema is not indicated. We proposed this evidence-based, individualized protocol for preoperative bowel preparation for the reference of our colleagues, in the hope of improving perioperative outcomes and reducing adverse events.
Collapse
|
7
|
Infants' developing sensitivity to native language phonotactics: A meta-analysis. Cognition 2021; 221:104993. [PMID: 34953268 DOI: 10.1016/j.cognition.2021.104993] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 12/07/2021] [Accepted: 12/13/2021] [Indexed: 11/03/2022]
Abstract
We used Bayesian modeling to aggregate experiments investigating infants' sensitivity to native language phonotactics. Our findings were based on data from 83 experiments on about 2000 infants learning 8 languages, tested using 4 different methods. Our results showed that, unlike with artificial languages, infants do exhibit sensitivity to native language phonotactic patterns in a lab setting. However, the exact developmental trajectory depends on the phonotactic pattern being tested. Before 8 months, infants tuned into non-local dependencies between vowels: specifically, vowel harmony. Between 8- and 10-months, infants demonstrated a consistent sensitivity to both local dependencies and non-local consonant dependencies. Sensitivity to non-local vowel dependencies that are not based on harmony emerged only after 10-months. These findings provide a benchmark for future experimental and computational research on the acquisition of phonotactics.
Collapse
|
8
|
[Meta analysis of diseased bowel resection versus diversion enterostomy in the treatment of late severe complications of chronic radiation-induced rectal injury]. ZHONGHUA WEI CHANG WAI KE ZA ZHI = CHINESE JOURNAL OF GASTROINTESTINAL SURGERY 2021; 24:1015-1023. [PMID: 34823303 DOI: 10.3760/cma.j.cn.441530-20210923-00380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Objective: To investigate the efficacy and safety of diseased bowel resection and diversion enterostomy in the treatment of late severe complications of chronic radiation-induced late rectal injury (RLRI). Methods: Studies about comparison of diseased bowel resection and diversion enterostomy in the treatment of late severe complications of chronic RLRI were screened and retrieved from databases, including PubMed, EMBASE, Scopus, Web of Science, Cochrane Library, CNKI, VIP, CBM and Wanfang. The following terms in Chinese were used to search [Title/Abstract]: radiation-induced intestinal injury, radiation proctitis, surgery. The following English terms were used to search: Radiation-induced intestinal injury, Bowel injury from radiation, Radiation proctitis, Surgery, Colostomy. Literature inclusion criteria: (1) studies with control groups, published at home and abroad publicly, about the postoperative effects of diseased bowel resection vs. diversion enterostomy on RLRI patients with late severe complications; (2) the period of the study performed in the literatures must be clear; (3) patients at the preoperative diagnosis for RLRI with refractory bleeding, narrow, obstruction, perforation or fistula, etc.; (4) diseased bowel resection included Hartmann, Dixon, Bacon and Parks; diversion enterostomy included colostomy and ileostomy; (5) if the studies were published by the same institution or authors at the same time, the study with the biggest sample size was chosen; studies conducted in different time with different subjects were simultaneously included; (6) at least one prognostic indicator of the following parameters should be included: the improvement of symptoms, postoperative complications, mortality, and reversed stomas rate. The stoma reduction rate was defined as the ratio of successful closure of colostomy after diseased bowel resection and diversion enterostomy. The method of direct calculation or the method of convert into direct calculation were used for stoma reduction rate. Exclusion criteria: (1) a single-arm study without control group; (2) RLRI patients did not undergo diseased bowel resection or diversion enterostomy at the first time; (3) RLRI patients with distant metastasis; (4) the statistical method in the study was not appropriate; (5) the information was not complete, such as a lack of prognosis in the observational indexes. After screening literatures according to criteria, data retrieval and quality evaluation were carried out. Review Manager 5.3 software was used for Meta-analysis. Sensitivity analysis was used to exam the stability of results. Funnel diagram was used to analyze the bias of publication. Results: A total of 11 literatures were enrolled, including 426 RLRI patients with late severe complications, of whom 174 underwent diseased bowel resection (resection group) and 252 underwent diversion enterostomy (diversion group), respectively. Compared with diversion group, although resection group had a higher morbidity of complication (35.1% vs. 15.9%, OR=2.67, 95% CI: 1.58 to 4.53, P<0.001), but it was more advantageous in symptom improvement (94.2% vs. 64.1%, OR=6.19, 95% CI: 2.47 to 15.52, P<0.001) and stoma reductions (62.8% vs. 5.1%, OR=15.17, 95% CI: 1.21 to 189.74, P=0.030), and the differences were significant (both P<0.05). No significant difference in postoperative mortality was found between the two groups (10.1% vs. 18.8%, OR=0.74, 95% CI: 0.21 to 2.59, P=0.640). There were no obvious changes between the two groups after sensitivity analysis for the prognostic indicators (the symptoms improved, postoperative complications, mortality, and reversed stomas rate) compared with the meta-analysis results before exclusion, suggesting that the results were robust and credible. Funnel diagram analysis suggested a small published bias. Conclusions: Chronic RLRI patients with late severe complications undergoing diseased bowel resection have higher risk of complication, while their long-term mortality is comparable to those undergoing diversion enterostomy. Diseased bowel resection is better in postoperative improvement of symptoms and stoma reduction rate.
Collapse
|
9
|
Expanding public health in China: an empirical analysis of healthcare inputs and outputs. Public Health 2016; 142:73-84. [PMID: 28057203 DOI: 10.1016/j.puhe.2016.10.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 08/18/2016] [Accepted: 10/12/2016] [Indexed: 11/16/2022]
Abstract
OBJECTIVES The Chinese Government claims that China's health policy is primarily focused on prevention. However, this does not appear to be the case. Researchers with an interest in China's health policy may be aware that the Chinese Government launched a health reform in 2009 to improve the health status of the entire population by 2020.1 This health reform has been in place for 7 years, and only 4 years now remain to achieve the overall objectives by 2020. This study analyzed the main inputs and outputs of China's health reform in order to identify the main problems and highlight the major challenges. It is hoped that this study will provide some reference for health reform in China and other developing countries. STUDY DESIGN This study focused on health, with human resources and healthcare costs as the main input indicators, and 2-week prevalence of illness and prevalence of non-communicable diseases as the main output indicators. By longitudinal comparison of real data from 2009 to 2014, the effects of China's health reform were analyzed to identify the main challenges, enabling suggestions to be made for future reference. METHODS This was a retrospective analysis of empirical data. Data were collected between 2009 and 2014 as follows: (1) data on the distribution of healthcare professionals were collected from the Statistical Bulletin of China's Health Development, issued by the National Health and Family Planning Commission every year between 2009 and 2014; (2) data on government health expenditure were obtained from the Annual National Public Fiscal Expenditure Data, released by the Financial Ministry of the People's Republic of China from 2009 to 2014; (3) data on the prevalence of chronic diseases, 2-week prevalence of illness, residents' medical service demands, and utilization of health services were obtained from the Fourth and Fifth National Health Care Surveys in 2008 and 2013; and (4) data on total healthcare expenditure, medical expenditure and out-of-pocket payments were obtained from the 2015 China Statistical Yearbook. RESULTS From 2009 to 2014, China's healthcare human resources were distributed primarily in hospitals that focus on providing treatment. By 2014, 62.5% of the health professionals and technical personnel were distributed in hospitals. From 2009, the Chinese Government spent more money on health care than previously, with approximately 67% spent on disease treatment and 14.19% spent on disease prevention. However, the 2-week prevalence of illness increased by 5.2 percentage points, and the prevalence of chronic diseases increased by 9 percentage points. Meanwhile, residents' out-of-pocket payments for health care were as high as 50.61% of the total healthcare expenditure and were particularly high in rural areas. CONCLUSION China should adjust the direction of its health reform as soon as possible to focus on improving health status rather than treatment of disease. In the future, as China's population ageing trend intensifies, China must take effective measures or the country's non-communicable disease rates will continue to increase. To meet this challenge, China's health reform should take effective measures to control the rising trend of the incidence of non-communicable diseases. First, China should focus on the core goal of its health reform policy, which is disease prevention. Second, China should focus on strengthening public health systems to effectively prevent and control key epidemic diseases. Third, China should increase the number of public health personnel, improve the level of education and training of public health personnel and increase the input of funds into the field of public health as soon as possible.
Collapse
|
10
|
Mapping QTLs for drought tolerance in an F2:3 population from an inter-specific cross between Gossypium tomentosum and Gossypium hirsutum. GENETICS AND MOLECULAR RESEARCH 2016; 15:gmr8477. [PMID: 27525919 DOI: 10.4238/gmr.15038477] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Cotton is one of the most important natural fiber crops in the world. Its growth and yield is greatly limited by drought. A quantitative trait locus (QTL) analysis was therefore conducted to investigate the genetic basis of drought tolerance in cotton (Gossypium spp) using 188 F2:3 lines developed from an inter-specific cross between a wild cotton species, G. tomentosum, and an upland cotton, G. hirsutum (CRI-12). A genetic map was constructed using 1295 simple sequence repeat markers, which amplified 1342 loci, distributed on 26 chromosomes, covering 3328.24 cM. A field experiment was conducted in two consecutive years (2014 and 2015) and 11 morphological and physiological traits were recorded under water-limited (W1)/well-watered (W2) regimes at three growth stages (bud, flowering, and full boll). The traits measured included chlorophyll content, plant height, leaf area, leaf number, leaf fresh weight, leaf dry weight, boll weight, number of bolls per plant, and the number of fruiting branches. Sixty-seven and 35 QTLs were found under the W1 and W2 conditions, respectively. Of these, the majority exhibited partial dominance or over-dominance genetic effects for increasing the trait values. Four consistent QTLs were found under the W1 treatment on chromosomes 5, 8, 9, and 16, whereas no consistent QTL was found in W2. Thirteen QTL clusters were also identified on nine chromosomes (2, 3, 5, 6, 9, 14, 15, 16, and 21). These results will help to elucidate the genetic basis of drought tolerance in cotton.
Collapse
|
11
|
Construction and characterization of a bacterial artificial chromosome library for the allotetraploid Gossypium tomentosum. GENETICS AND MOLECULAR RESEARCH 2015; 14:16975-80. [PMID: 26681044 DOI: 10.4238/2015.december.15.3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Gossypium tomentosum is a wild allotetraploid species with the (AD)5 genome. It is characterized by many useful traits including finer fiber fineness, drought tolerance, and Fusarium and Verticillium resistance. We constructed the first bacterial artificial chromosome library for Gossypium tomentosum. With high quality and broad coverage, this library includes 200,832 clones, with an average insert size of about 122 kb and fewer than 3% empty clones. Our library is approximately 10-fold the size of the (AD)5-genome (2400 Mb) and provides a 99.7% probability of isolating genes of interest or their sequences. Seven of eight simple sequence repeats markers that are located on five different chromosomes and linked with resistance to Verticillium wilt could amplify the 50 superpools and obtained one to five hits. This high capacity library will be an important genomic resource for classifying and analyzing the evolution of allotetraploid cotton species as well as for isolating disease-resistance and drought-tolerance genes.
Collapse
|
12
|
Genetic diversity and relationship analysis of Gossypium arboreum accessions. GENETICS AND MOLECULAR RESEARCH 2015; 14:14522-9. [PMID: 26600511 DOI: 10.4238/2015.november.18.15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Simple sequence repeat techniques were used to identify the genetic diversity of 101 Gossypium arboreum accessions collected from India, Vietnam, and the southwest of China (Guizhou, Guangxi, and Yunnan provinces). Twenty-six pairs of SSR primers produced a total of 103 polymorphic loci with an average of 3.96 polymorphic loci per primer. The average of the effective number of alleles, Nei's gene diversity, and Shannon's information index were 0.59, 0.2835, and 0.4361, respectively. The diversity varied among different geographic regions. The result of principal component analysis was consistent with that of unweighted pair group method with arithmetic mean clustering analysis. The 101 G. arboreum accessions were clustered into 2 groups.
Collapse
|
13
|
Characterization and development of chloroplast microsatellite markers for Gossypium hirsutum, and cross-species amplification in other Gossypium species. GENETICS AND MOLECULAR RESEARCH 2015; 14:11924-32. [PMID: 26505340 DOI: 10.4238/2015.october.5.6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Cotton is an important economic crop worldwide; its fiber, commonly known as cotton lint, is the main natural source for the textile industry. Sixty chloroplast microsatellites were identified and characterized from the complete sequence of the Gossypium hirsutum chloroplast genome using a bioinformatic approach. Twenty chloroplast microsatellite loci were polymorphic in the 66 Gossypium germplasm accessions. A total of 85 alleles were detected, with allele numbers varying from 2-7 per locus. Polymorphism information content varied from 0.02-0.66, with a mean of 0.48. Additionally, transferability of the 20 polymorphic chloroplast microsatellite primers was evaluated in other 31 Gossypium species. Sixteen markers were successfully amplified across all species tested, while the remaining 4 markers cross-amplified in most species tested. These polymorphic chloroplast microsatellite markers may be useful tool for studies of individual identification, genetic diversity, evolution, conservation genetics, and molecular breeding in Gossypium.
Collapse
|
14
|
Volumetric deformation of live cells induced by pressure-activated cross-membrane ion transport. PHYSICAL REVIEW LETTERS 2014; 113:118101. [PMID: 25260007 DOI: 10.1103/physrevlett.113.118101] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Indexed: 06/03/2023]
Abstract
In this work, we developed a method that allows precise control over changes in the size of a cell via hydrostatic pressure changes in the medium. Specifically, we show that a sudden increase, or reduction, in the surrounding pressure, in the physiologically relevant range, triggers cross-membrane fluxes of sodium and potassium ions in leukemia cell lines K562 and HL60, resulting in reversible volumetric deformation with a characteristic time of around 30 min. Interestingly, healthy leukocytes do not respond to pressure shocks, suggesting that the cancer cells may have evolved the ability to adapt to pressure changes in their microenvironment. A model is also proposed to explain the observed cell deformation, which highlights how the apparent viscoelastic response of cells is governed by the microscopic cross-membrane transport.
Collapse
|
15
|
Expression of TRPV6 and CaBP-D28k in the egg shell gland (uterus) during the oviposition cycle of the laying hen. Br Poult Sci 2014; 54:398-406. [PMID: 23796121 DOI: 10.1080/00071668.2013.791385] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
1. The aim of this study was to investigate the localisation of the transient receptor potential vanilloid channel type 6 (TRPV6) in egg shell gland (ESG) and examine the dynamic expression of TRPV6 and Calbindin-d28k (CaBP-D28k), as well as the changes in concentration of total calcium (Ca), total inorganic phosphorus (P), alkaline phosphatase (ALP), parathyroid hormone (PTH) and calcitonin (CT) in plasma during the oviposition cycle. 2. The plasma ALP activity was notably increased at 8 h. In addition, plasma CT was highest at 0 h and significantly lower at 8 h. The change of plasma PTH concentration increased slightly post-oviposition and reached a maximum at 16 h. 3. Immunohistochemical analysis indicated that TRPV6 was strongly localised to the apical luminal epithelium of the mucosa. The mRNA levels of TRPV6 and CaBP-D28k in the ESG remained very low from 0 to 4.5 h, but were significantly increased at 16 h. Furthermore, Western blotting analysis showed that the expression of TRPV6 and CaBP-D28k also reached a maximum at 16 h and was different from the concentration of CaBP-D28k. 4. In conclusion, the epithelial Ca(2+) channel TRPV6 is strongly expressed in the epithelial cells of the eggshell gland, and the increase of TRPV6 and CaBP-D28k mRNA and protein expression during eggshell formation suggests that active Ca(2+) transcellular transport exerts significant effects in delivering active calcium in the ESG.
Collapse
|
16
|
Frequency-dependent cell death by optical tweezers manipulation. J Cell Physiol 2013; 228:2037-41. [PMID: 23553530 DOI: 10.1002/jcp.24369] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Accepted: 03/19/2013] [Indexed: 11/06/2022]
Abstract
Optical tweezers were used to scan individual Chronic Myelogenous Leukemia cells to determine if the cell death depends on the scanning conditions. Although increasing the scanning frequency or amplitude means greater force applied to the cells, their effects on cell death are not a simple increasing trend, as observed in the optical microscopy. Indeed, cell death sharply increased at particular screening frequencies and amplitudes, whereas other frequencies or amplitudes were less detrimental. These results suggest that cell damage was more sensitive to certain scanning conditions, rather than simply high-applied forces.
Collapse
|
17
|
Changes of blood parameters associated with bone remodeling following experimentally induced fatty liver disorder in laying hens. Poult Sci 2013; 92:1443-53. [PMID: 23687138 DOI: 10.3382/ps.2012-02800] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Studies have demonstrated that obesity and osteoporosis are linked disorders in humans. This study examined the hypothesis that excessive lipid consumption affects bone metabolism in laying hens. A total of one hundred 63-wk-old laying hens were randomly divided into 2 treatments and fed either a regular layer diet (control) or a high energy and low protein diet (HE-LP; experimental treatment) for 80 d. Egg production, feed intake, and BW were recorded at various days during the treatment. At d 80, ten randomly chosen birds per treatment group were killed. Abdominal fat weight, liver weight, and liver fat content were determined. Serum levels of total calcium, inorganic phosphate, and alkaline phosphatase were measured using a biochemical analyzer. Serum concentrations of osteocalcin, leptin-like protein, and estrogen were measured by enzyme-linked immunosorbent assay. Tibia length and width were measured using a vernier caliper; density of the right tibias was determined using an x-ray scanner; and mechanical properties of the left tibias were analyzed using a material testing machine. The expression of osteocalcin and osteoprotegerin mRNA in the keel bone was analyzed by real-time PCR. The concentration of osteocalcin protein in the keels was measured using western blot. Compared with control hens, hens fed the HE-LP diet had lower egg production, lower feed intake, greater liver fat content, and greater abdominal fat pad mass (P < 0.05). Feeding the HE-LP diet increased serum alkaline phosphatase activity, osteocalcin, leptin-like protein, and estrogen concentrations (P < 0.05), and decreased the keel osteocalcin concentrations (P < 0.05). There were significant positive correlations between the serum concentrations of leptin-like protein, estrogen, and osteocalcin regardless of treatment (P < 0.05). The results indicated that HE-LP diet induced a fatty liver disorder in laying hens with an upregulation in bone turnover and exacerbated skeletal damage. The data supported a role for lipid metabolism in skeletal heath of laying hens.
Collapse
|
18
|
Abstract
The protein-protein interactions between hepatitis B surface antigen (HBsAg) and its antibodies (anti-HBs) were studied by measuring the binding force between microspheres coated with such proteins using optical tweezers. The interaction force between the protein-coated microspheres was found to be strongly influenced by the acidity of the surrounding liquid medium, as well as the experimental temperature, and it reaches a maximum value at around pH 7.5 and temperature around 37°C. By measuring the protein distribution on the surfaces of the microspheres and their contact areas using scanning electron microscopy, the specific binding force between an HBsAg and anti-HBs protein pair is estimated to be around 4.8 pN at the optimum pH value and temperature at an applied loading rate of around 1 pN/s.
Collapse
|
19
|
Localisation and expression of TRPV6 in all intestinal segments and kidney of laying hens. Br Poult Sci 2012; 52:507-16. [PMID: 21919579 DOI: 10.1080/00071668.2011.596994] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
1. The aim of this study was to investigate the localisation and expression of the epithelial Ca2+ channel TRPV6 (transient receptor potential vanilloid channel type 6) in different intestinal segments and kidney of laying hens during peak lay. 2. Immunohistochemical analysis of the intestine indicated that TRPV6 was localised to the brush-border membranes of the duodenum, jejunum, ileum, caecum, and rectum. Expression was weaker in the rectum, and little or no expression was found in crypt and goblet cells. In addition, TRPV6 mRNA was quantified amongst different intestinal segments, and expression was highest in the duodenum and jejunum. Furthermore, Western blotting indicated that the duodenum expressed the greatest amount of TRPV6 and the rectum the least with the other segments expressing intermediate levels. 3. In the kidney, distinct immunopositive staining for TRPV6 was detected at the apical domain of the distal convoluted tubules (DCT) and medullary connecting tubules (CNT). Interestingly, distribution of TRPV6 extended to the proximal convoluted tubules (PCT). Furthermore, the kidney expressed lower TRPV6 mRNA and protein levels compared with that in the duodenum. 4. In conclusion, the epithelial Ca2+ channel TRPV6 is strongly expressed in the apical cells of the entire intestine and the renal tubules, suggesting that active Ca2+ transcellular transport plays a crucial role in dietary calcium (re)absorption in laying hens.
Collapse
|
20
|
Reliable measurement of elastic modulus of cells by nanoindentation in an atomic force microscope. J Mech Behav Biomed Mater 2011; 8:134-42. [PMID: 22402160 DOI: 10.1016/j.jmbbm.2011.11.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 11/04/2011] [Accepted: 11/07/2011] [Indexed: 01/02/2023]
Abstract
The elastic modulus of an oral cancer cell line UM1 is investigated by nanoindentation in an atomic force microscope with a flat-ended tip. The commonly used Hertzian method gives apparent elastic modulus which increases with the loading rate, indicating strong effects of viscoelasticity. On the contrary, a rate-jump method developed for viscoelastic materials gives elastic modulus values which are independent of the rate-jump magnitude. The results show that the rate-jump method can be used as a standard protocol for measuring elastic stiffness of living cells, since the measured values are intrinsic properties of the cells.
Collapse
|
21
|
Measurements of h(c)(1P(1)) in psi' decays. PHYSICAL REVIEW LETTERS 2010; 104:132002. [PMID: 20481873 DOI: 10.1103/physrevlett.104.132002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Indexed: 05/29/2023]
Abstract
We present measurements of the charmonium state h(c)(1P(1)) made with 106x10(6) psi' events collected by BESIII at BEPCII. Clear signals are observed for psi'-->pi0 h(c) with and without the subsequent radiative decay h(c)-->gamma eta(c). First measurements of the absolute branching ratios B(psi'-->pi0 h(c)) = (8.4+/-1.3+/-1.0) x 10(-4) and B(h(c)-->gamma eta(c)) = (54.3+/-6.7+/-5.2)% are presented. A statistics-limited determination of the previously unmeasured h(c) width leads to an upper limit Gamma(h(c))<1.44 MeV (90% confidence). Measurements of M(h(c)) = 3525.40+/-0.13+/-0.18 MeV/c2 and B(psi'-->pi0 h(c)) x B(h(c)-->gamma eta(c)) = (4.58+/-0.40+/-0.50) x 10(-4) are consistent with previous results.
Collapse
|
22
|
Comparison of approaches for efficient gene silencing induced by microRNA-based short hairpin RNA and indicator gene expression. Mol Biol Rep 2010; 37:1831-9. [PMID: 19603286 DOI: 10.1007/s11033-009-9618-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Accepted: 07/02/2009] [Indexed: 10/20/2022]
Abstract
MicroRNA-based short hairpin RNAs (shRNAs) are natural inducers of RNA interference and have been increasingly used in shRNA expression strategies. In the present study, we compared the efficiencies of exogenous green fluorescence protein (GFP) and endogenous glyceraldehyde-3-phosphate dehydrogenase (GAPDH) knockdown and red fluorescent protein (RFP) indicator expression mediated by three differently designed plasmids. RFP was introduced either at the 5' end, at the 3' end of the human mir155-based target gene (TG) (e.g., GFP or GAPDH) shRNA expression cassette (EC), or at the 3' end of the chimeric intron-containing TG shRNA EC. Comparisons with the control vector showed an obvious reduction of GFP or GAPDH expression with the various shRNA expression plasmids (P < 0.05). When RFP was located at the 5' end or at the 3' end of the TG shRNA EC, RFP expression was low; whereas when RFP was connected with the chimeric intron-containing TG shRNA EC, RFP expression was high. Taken together, this study demonstrated an efficient plasmid design for both TG silencing induced by microRNA-based shRNA and indicator gene expression in vitro.
Collapse
|
23
|
A high sensitivity gas sensor for formaldehyde based on CdO and In(2)O(3) doped nanocrystalline SnO(2). NANOTECHNOLOGY 2008; 19:095506. [PMID: 21817673 DOI: 10.1088/0957-4484/19/9/095506] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The gas-sensing characteristics of In(2)O(3) and CdO doped nanocrystalline SnO(2) compounds for formaldehyde were investigated in this study. The phases of the resulting materials and the morphologies of the sensing layers were characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Indirect-heating sensors using SnO(2)-In(2)O(3)-CdO compounds as sensitive materials were fabricated on an alumina tube with Au electrodes and platinum wires. All measurements were performed at several operating temperatures from 100 to 180 °C. Good gas-sensing responses to formaldehyde have been found for all the prepared samples. It is shown that the sensors exhibited high sensitivity at low operating temperature (133 °C), making them promising candidates for practical detectors for formaldehyde.
Collapse
|
24
|
Relativistic effects and two-body currents in (H)((-->)e(')p)n using out-of-plane detection. PHYSICAL REVIEW LETTERS 2001; 87:172301. [PMID: 11690266 DOI: 10.1103/physrevlett.87.172301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2001] [Indexed: 05/23/2023]
Abstract
Measurements of the (2)H((-->)e,e(')p)n reaction were performed with the out-of-plane magnetic spectrometers (OOPS) at the MIT-Bates Linear Accelerator. The longitudinal-transverse, f(LT) and f(')(LT), and the transverse-transverse, f(TT), interference responses at a missing momentum of 210 MeV/c were simultaneously extracted in the dip region at Q2 = 0.15 (GeV/c)(2). In comparison to models of deuteron electrodisintegration, the data clearly reveal strong effects of relativity and final-state interactions and the importance of two-body meson-exchange currents and isobar configurations. We demonstrate that such effects can be disentangled by extracting these responses using the novel out-of-plane technique.
Collapse
|
25
|
[Study on effect of Astragalus injection in treating congestive heart failure]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 2001; 21:747-9. [PMID: 12575607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To observe the clinical efficacy and side-effects of Astragalus Injection (AI) in treating congestive heart failure (CHF). METHODS Eighty-three patients of CHF with heart function of II-IV grade assessed by NYHA (New York Heart Association) classification were randomly divided into 2 groups. The 42 patients in the treated group were treated with AI 40 ml (equivalent to 80 g crude drug) by adding in 5% glucose solution 500 ml for intravenous dripping, once a day and the 41 patients in the control group were treated by nitrolingual injection 15 mg by adding in 5% glucose solution 500 ml for intravenous dripping once a day. The therapeutic course in both groups was 2 weeks and the patients were followed-up for 1-6 months. RESULTS The clinical heart function improvement rate and the total effective rate in the treated group after 1 month treatment were 26.2% and 78.6%, and after 6 months were 34.2% and 81.6% respectively, which were superior to those in the control group significantly (P < 0.05 or P < 0.01). The levels of left ventricular ejection fraction (LVEF), fractional shortening of left ventricular short axis (FS), the ratio of maximum blood flow between the advanced and early atrial systole (E/A), stroke volume (SV), cardiac output (CO) and the cardiac index (CI) were all improved in both groups (P < 0.01 or P < 0.05), but better improvement was shown in the treated group. Follow-up study showed that the incidence of cardiac event was lower in the treated group than that in the control group (P < 0.05). CONCLUSION AI can be took as one of the important auxiliary drugs for treatment of CHF especially in severe cases.
Collapse
|
26
|
Synthesis and SAR of 5-, 6-, 7- and 8-aza analogues of 3-aryl-4-hydroxyquinolin-2(1H)-one as NMDA/glycine site antagonists. Bioorg Med Chem 2001; 9:2061-71. [PMID: 11504642 DOI: 10.1016/s0968-0896(01)00115-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of 5-, 6-, 7- and 8-aza analogues of 3-aryl-4-hydroxyquinolin-2(1H)-one was synthesized and assayed as NMDA/glycine receptor antagonists. The in vitro potency of these antagonists was determined by displacement of the glycine site radioligand [(3)H]5,7-dicholorokynurenic acid ([(3)H]DCKA) in rat brain cortical membranes. Selected compounds were also tested for functional antagonism using electrophysiological assays in Xenopus oocytes expressing cloned NMDA receptor (NR) 1A/2C subunits. Among the 5-, 6-, 7-, and 8-aza-3-aryl-4-hydroxyquinoline-2(1H)-ones investigated, 5-aza-7-chloro-4-hydroxy-3-(3-phenoxyphenyl)quinolin-2-(1H)-one (13i) is the most potent antagonist, having an IC(50) value of 110 nM in [(3)H]DCKA binding and a K(b) of 11 nM in the electrophysiology assay. Compound 13i is also an active anticonvulsant when administered systemically in the mouse maximum electroshock-induced seizure test (ED(50)=2.3mg/kg, IP).
Collapse
|
27
|
Dynamics of the 16O(e, e'p) reaction at high missing energies. PHYSICAL REVIEW LETTERS 2001; 86:5670-5674. [PMID: 11415329 DOI: 10.1103/physrevlett.86.5670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2000] [Indexed: 05/23/2023]
Abstract
We measured the cross section and response functions for the quasielastic 16O(e,e'p) reaction for missing energies 25< or =E(m)< or =120 MeV at missing momenta P(m)< or =340 MeV/c. For 25<E(m)<50 MeV and P(m) approximately 60 MeV/c, the reaction is dominated by a single 1s(1/2) proton knockout. At larger P(m), the single-particle aspects are increasingly masked by more complicated processes. Calculations which include pion exchange currents, isobar currents, and short-range correlations account for the shape and the transversity, but for only half of the magnitude of the measured cross section.
Collapse
|
28
|
Chemokines and chemokine receptors in inflammation of the nervous system: manifold roles and exquisite regulation. Immunol Rev 2000; 177:52-67. [PMID: 11138785 DOI: 10.1034/j.1600-065x.2000.17709.x] [Citation(s) in RCA: 189] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This article focuses on the production of chemokines by resident glial cells of the nervous system. We describe studies in two distinct categories of inflammation within the nervous system: immune-mediated inflammation as seen in experimental autoimmune encephalomyelitis (EAE) or multiple sclerosis (MS) and post-traumatic inflammation. We provide evidence that chemokines play a role in amplifying the inflammatory reaction in EAE (and, probably, MS). In the context of neural trauma, chemokines appear to be primary stimuli for leukocyte recruitment. Strikingly, expression of monocyte chemoattractant protein (MCP)-1 and interferon-gamma-inducible protein-10 (IP-10) are largely restricted to astrocytes or other glial cells in these diverse pathological states. The remainder of the review focuses on studies that address the molecular mechanisms which underlie transcriptional regulation of three astrocyte-derived chemokines: MCP-1, IP-10 and beta-R1/interferon-gamma-inducible T-cell chemoattractant (I-TAC). Based on these studies, we propose that the complex promoters of these genes are marvelously organized for flexible and efficient response to challenge. In the case of MCP-1, several different stimuli can elicit gene transcription, acting through a conserved mechanism that includes binding of inducible transcription factors and recruitment of the constitutive factor Sp1. For IP-10 and beta-R1/I-TAC, it appears that efficient gene transcription occurs only in highly inflammatory circumstances that produce aggregates of simultaneous stimuli. These characteristics, in turn, mirror the expression patterns of the endogenous genes: MCP-1 is expressed under a variety of circumstances, while IP-10 appears primarily during immune-mediated processes that feature exposure of resident neuroglia to high levels of inflammatory cytokines.
Collapse
|
29
|
Abstract
Mono-halogenated derivatives of the calcium indicators fura-2 and indo-1 were synthesized and their spectroscopic properties evaluated. Halogenation ortho or para to the bridging oxygen in the BAPTA nucleus had a more pronounced weakening effect on binding affinity than in the meta position in the fura derivatives. Two new excitation ratioable fluorescent calcium indicators, benzothiaza-1 and 2, were also synthesized. Kd values of 400 nM to 5.3 microM [Ca2+] were observed in these families of new probes.
Collapse
|
30
|
Synthesis of N-substituted 4-(4-hydroxyphenyl)piperidines, 4-(4-hydroxybenzyl)piperidines, and (+/-)-3-(4-hydroxyphenyl)pyrrolidines: selective antagonists at the 1A/2B NMDA receptor subtype. J Med Chem 2000; 43:984-94. [PMID: 10715162 DOI: 10.1021/jm990428c] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Antagonists at the 1A/2B subtype of the NMDA receptor (NR1A/2B) are typically small molecules that consist of a 4-benzyl- or a 4-phenylpiperidine with an omega-phenylalkyl substituent on the heterocyclic nitrogen. Many of these antagonists, for example ifenprodil (1), incorporate a 4-hydroxy substituent on the omega-phenyl group. In this study, the position of this 4-hydroxy substituent was transferred from the omega-phenyl group to the benzyl or phenyl group located on the 4-position of the piperidine ring. Analogues incorporating pyrrolidine in lieu of piperidine were also prepared. Electrical recordings using cloned receptors expressed in Xenopus oocytes show that high-potency antagonists at the NR1A/2B subtype are obtained employing N-(omega-phenylalkyl)-substituted 4-(4-hydroxyphenyl)piperidine, 4-(4-hydroxybenzyl)piperidine, and (+/-)-3-(4-hydroxyphenyl)pyrrolidine as exemplified by 21 (IC(50) = 0.022 microM), 33 (IC(50) = 0.059 microM), and 40 (IC(50) = 0.017 microM), respectively. These high-potency antagonists are >1000 times more potent at the NR1A/2B subtype than at either the NR1A/2A or NR1A/2C subtypes. The binding affinities of 21 at alpha(1)-adrenergic receptors ([(3)H]prazosin, IC(50) = 0.54 microM) and dopamine D2 receptors ([(3)H]raclopride, IC(50) = 1.2 microM) are reduced by incorporating a hydroxy group onto the 4-position of the piperidine ring and the beta-carbon of the N-alkyl spacer to give (+/-)-27: IC(50) NR1A/2B, 0.026; alpha(1), 14; D2, 105 microM. The high-potency phenolic antagonist 21 and its low-potency O-methylated analogue 18 are both potent anticonvulsants in a mouse maximal electroshock-induced seizure (MES) study (ED(50) (iv) = 0.23 and 0.56 mg/kg, respectively). These data indicate that such compounds penetrate the blood-brain barrier but their MES activity may not be related to NMDA receptor antagonism.
Collapse
|
31
|
Differing effects of N-methyl-D-aspartate receptor subtype selective antagonists on dyskinesias in levodopa-treated 1-methyl-4-phenyl-tetrahydropyridine monkeys. J Pharmacol Exp Ther 1999; 290:1034-40. [PMID: 10454475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
The antiparkinsonian and antidyskinetic profile of two N-methyl-D-aspartate (NMDA) receptor antagonists, a competitive antagonist, (R)-4-oxo-5-phosphononorvaline (MDL 100,453), and a novel noncompetitive allosteric site antagonist, 4-hydroxy-N-[2-(4-hydroxyphenoxy)ethyl]-4-(4-methylbenzyl)piper idi ne (Co 101244/PD 174494), was assessed in six levodopa-treated 1-methyl-4-phenyl-tetrahydropyridine-lesioned parkinsonian monkeys. The effects on motor function of these two drugs, alone and in combination with levodopa, were then correlated with NMDA subtype selectivity and apparent affinity for four diheteromeric NMDA receptor subunit combinations expressed in Xenopus oocytes. MDL 100, 453 (300 mg/kg s.c.) by itself increased global motor activity (p =. 0005 versus vehicle) and administered 15 min after a low dose of levodopa/benserazide s.c., MDL 100,453 (50, 300 mg/kg s.c.) showed dose-dependent potentiation of antiparkinsonian responses and also produced dyskinesias. Following injection of a fully effective dose of levodopa, MDL 100,453 (300 mg/kg s.c.) also produced a 25% increase in mean dyskinesia score (p =.04). In contrast, Co 101244 did not change motor activity by itself and only showed a tendency to potentiate the antiparkinsonian response when given in combination with a low dose of levodopa, which did not attain statistical significance. However, with a high dose of levodopa, Co 101244 (0.1, 1 mg/kg s.c.) displayed antidyskinetic effects (67 and 71% reduction, respectively) while sparing levodopa motor benefit. In vitro, MDL 100,453 was an NMDA glutamate-site antagonist, with approximately 5- to 10-fold selectivity for the NR1A/NR2A subtype combination (K(b) = 0.6 microM) versus NR1A in combination with 2B, 2C, or 2D. In contrast, the allosteric site antagonist Co 101244 showed approximately 10,000-fold selectivity for the NR1A/NR2B (IC(50) = 0.026 microM) versus the other three subunit combinations tested. Taken together, the data suggest that the NR2 subunit selectivity profile of NMDA receptor antagonists can play an important role in predicting behavioral outcome and offer more evidence that NR2B-selective NMDA receptor antagonists may be useful agents in the treatment of Parkinson's disease.
Collapse
|
32
|
Structure-activity relationship of N-(phenylalkyl)cinnamides as novel NR2B subtype-selective NMDA receptor antagonists. J Med Chem 1999; 42:3412-20. [PMID: 10464027 DOI: 10.1021/jm990199u] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A novel series of N-(phenylalkyl)cinnamides related to N-(4-phenylbutyl)-3,4-dihydroxy-beta-cyanocinnamide (6, an EGFR-K inhibitor with high antiproliferative activity) was synthesized and tested for antagonism at N-methyl-D-aspartate (NMDA) receptor subtypes. Potency and subunit selectivity were assayed by electrical recordings in Xenopus oocytes expressing three binary combinations of cloned rat NMDA receptor subunits: NR1A expressed in combination with either NR2A, NR2B, or NR2C. The N-(phenylalkyl)cinnamides are selective antagonists of NR1A/2B receptors. Assayed under steady-state conditions, N-(4-phenylbutyl)-4-hydroxycinnamide (16) has an IC(50) value of 77 nM and >1000-fold selectivity with respect to NR1A/2A and NR1A/2C receptors. Potency at alpha(1) adrenergic receptors is low for the four cinnamides tested. Inhibition of NR1A/2B receptors does not correlate with EGFR and ErbB2/neu tyrosine kinase inhibitor activity. The N-(phenylalkyl)cinnamide series we describe provides a novel and structurally diverse framework for designing new NR2B-selective NMDA antagonists as potential CNS therapeutics.
Collapse
|
33
|
4-Hydroxy-1-[2-(4-hydroxyphenoxy)ethyl]-4-(4-methylbenzyl)piperidine: a novel, potent, and selective NR1/2B NMDA receptor antagonist. J Med Chem 1999; 42:2993-3000. [PMID: 10425109 DOI: 10.1021/jm990246i] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A structure-based search and screen of our compound library identified N-(2-phenoxyethyl)-4-benzylpiperidine (8) as a novel N-methyl-D-aspartate (NMDA) receptor antagonist that has high selectivity for the NR1/2B subunit combination (IC(50) = 0.63 microM). We report on the optimization of this lead compound in terms of potency, side effect liability, and in vivo activity. Potency was assayed by electrical recordings in Xenopus oocytes expressing cloned rat NMDA receptors. Side effect liability was assessed by measuring affinity for alpha(1)-adrenergic receptors and inhibition of neuronal K(+) channels. Central bioavailability was gauged indirectly by determining anticonvulsant activity in a mouse maximal electroshock (MES) assay. Making progressive modifications to 8, a hydroxyl substituent on the phenyl ring para to the oxyethyl tether (10a) resulted in a approximately 25-fold increase in NR1A/2B potency (IC(50) = 0.025 microM). p-Methyl substitution on the benzyl ring (10b) produced a approximately 3-fold increase in MES activity (ED(50) = 0.7 mg/kg iv). Introduction of a second hydroxyl group into the C-4 position on the piperidine ring (10e) resulted in a substantial decrease in affinity for alpha(1) receptors and reduction in inhibition of K(+) channels with only a modest decrease in NR1A/2B and MES potencies. Among the compounds described, 10e (4-hydroxy-N-[2-(4-hydroxyphenoxy)ethyl]-4-(4-methylbenzyl)piperid ine, Co 101244/PD 174494) had the optimum pharmacological profile and was selected for further biological evaluation.
Collapse
|
34
|
Subtype-selective N-methyl-D-aspartate receptor antagonists: synthesis and biological evaluation of 1-(arylalkynyl)-4-benzylpiperidines. J Med Chem 1999; 42:2469-77. [PMID: 10395488 DOI: 10.1021/jm990148x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A search of our compound library for compounds with structural similarity to ifenprodil (5) and haloperidol (7) followed by in vitro screening revealed that 4-benzyl-1-(4-phenyl-3-butynyl)piperidine (8) was a moderately potent and selective antagonist of the NR1A/2B subtype of NMDA receptors. Substitution on the benzyl group of 8 did not significantly affect NR1A/2B potency, while addition of hydrogen bond donors in the para position of the phenyl group enhanced NR1A/2B potency. Addition of a hydroxyl moiety to the 4-position of the piperidine group slightly reduced NR1A/2B potency while reducing alpha-1 adrenergic and dopamine D2 receptor binding affinities substantially, resulting in improved overall selectivity for NR1A/2B receptors. Finally, the butynyl linker was replaced with propynyl or pentynyl. When the phenyl was para substituted with amine or acetamide groups, the NR1A/2B potency order was butynyl > pentynyl >> propynyl. For the para methanesulfonamide or hydroxyl groups, the order was butynyl approximately propynyl > pentynyl. The hydroxyl propyne (48) and butyne (23) were among the most potent NR1A/2B antagonists from this study. They both potentiated the effects of L-DOPA in the 6-hydroxydopamine-lesioned rat, a model of Parkinson's disease, dosed at 10 mg/kg ip, but 48 was not active at 30 mg/kg po.
Collapse
|
35
|
Structure-activity relationships for a series of bis(phenylalkyl)amines: potent subtype-selective inhibitors of N-methyl-D-aspartate receptors. J Med Chem 1998; 41:3499-506. [PMID: 9719603 DOI: 10.1021/jm980235+] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A series of bis(phenylalkyl)amines, structural analogues of ifenprodil and nylidrin, were synthesized and tested for antagonism of N-methyl-D-aspartate (NMDA) receptors. Potency and subunit selectivity were assayed by electrical recordings in Xenopus oocytes expressing three binary combinations of cloned rat NMDA receptor subunits: NR1A expressed in combination with either NR2A, NR2B, or NR2C. The bis(phenylalkyl)amines were selective antagonists of NR1A/2B receptors. Assayed under steady-state conditions, the most potent of these, N-[2-(4-hydroxyphenyl)ethyl]-5-phenylpentylamine hydrochloride (20), has an IC50 value of 8 nM and >1000-fold selectivity with respect to NR1A/2A and NR1A/2C receptors. The structure-activity relationship of the bis(phenylalkyl)amine series indicates that the piperidine ring and alkyl chain substitutions common to NR2B-selective antagonists such as ifenprodil, CP 101,606, and Ro 25-6981 are not necessary to generate potent and selective ligands. The primary determinants of potency are the phenolic OH group, acting as a hydrogen bond donor, the distance between the two rings, and an electrostatic interaction between the receptor and the basic nitrogen atom. This study provides a framework for designing structurally novel NR2B-selective antagonists which may be useful for treatment of a variety of neurological disorders.
Collapse
|
36
|
Structure-activity relationships of alkyl- and alkoxy-substituted 1,4-dihydroquinoxaline-2,3-diones: potent and systemically active antagonists for the glycine site of the NMDA receptor. J Med Chem 1997; 40:730-8. [PMID: 9057859 DOI: 10.1021/jm960654b] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We report on a series of alkyl- and alkoxy-substituted 1,4-dihydroquinoxaline-2,3-diones (QXs), prepared as a continuation of our structure-activity relationship (SAR) study of QXs as antagonists for the glycine site of the N-methyl-D-aspartate (NMDA) receptor. The in vitro potency of these antagonists was determined by displacement of the glycine site radioligand [3H]-5,7-dichlorokynurenic acid ([3H]DCKA) in rat brain cortical membranes. In general, methyl is a good replacement for chloro or bromo in the 6-position, and alkoxy-substituted QXs have lower potencies than alkyl- or halogen-substituted QXs. Ethyl-substituted QXs are generally less potent than methyl-substituted QXs, especially in the 6-position of 5,6,7-trisubstituted QXs. Fusion of a ring system at the 6,7-positions results in QXs with low potency. Several methyl-substituted QXs are potent glycine site antagonists that have surprisingly high in vivo activity in the maximal electroshock (MES) test in mice. Among these, 7-chloro-6-methyl-5-nitro QX (14g) (IC50 = 5 nM) and 7-bromo-6-methyl-5-nitro QX (14f) (IC50 = 9 nM) are comparable in potency to 6,7-dichloro-5-nitro QX (2) (ACEA 1021) as glycine site antagonists. QX 14g has an ED50 value of 1.2 mg/kg iv in the mouse MES assay. Interestingly, alkyl QXs with log P values of 0.5 or less tend to be more bioavailable than QXs with higher log P values. QX 14g has 440-fold selectivity for NMDA vs alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, as determined electrophysiologically under steady-state conditions in oocytes expressing rat cerebral cortex poly(A)+ RNA. Overall, 14g was found to have the best combination of in vitro and in vivo potency of all the compounds tested in this and previous studies on the QX series.
Collapse
|
37
|
Structure-activity relationships of 4-hydroxy-3-nitroquinolin-2(1H)-ones as novel antagonists at the glycine site of N-methyl-D-aspartate receptors. J Med Chem 1996; 39:4682-6. [PMID: 8917657 DOI: 10.1021/jm960520y] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A series of 4-hydroxy-3-nitroquinolin-2(1H)-ones (HNQs) was synthesized by nitration of the corresponding 2,4-quinolinediols. The HNQs were evaluated as antagonists at the glycine site of NMDA receptors by inhibition of [3H]DCKA binding to rat brain membranes. Selected HNQs were also tested for functional antagonism by electrophysiological assays in Xenopus oocytes expressing either 1a/2C subunits of NMDA receptors or rat brain AMPA receptors. The structure-activity relationships (SAR) of HNQs showed that substitutions in the 5-, 6-, and 7-positions in general increase potency while substitutions in the 8-position cause a sharp reduction in potency. Among the HNQs tested, 5,6,7-trichloro HNQ (8i) was the most potent antagonist with an IC50 of 220 nM in [3H]DCKA binding assay and a Kb of 79 nM from electrophysiological assays. Measured under steady-state conditions HNQ 8i is 240-fold selective for NMDA over AMPA receptors. The SAR of HNQs was compared with those of 1,4-dihydroquinoxaline-2,3-diones (QXs) and 1,2,3,4-tetrahydroquinoline-2,3,4-trione 3-oximes (QTOs). In general, HNQs have similar potencies to QXs with the same benzene ring substitution pattern but are about 10 times less active than the corresponding QTOs. HNQs are more selective for NMDA receptors than the corresponding QXs and QTOs. The similarity of the SAR of HNQs, QXs, and QTOs suggested that these three classes of antagonists might bind to the glycine site in a similar manner. With appropriate substitutions, HNQs represent a new class of potent and highly selective NMDA receptor glycine site antagonists.
Collapse
|
38
|
Synthesis and structure-activity relationships of 1,2,3,4-tetrahydroquinoline-2,3,4-trione 3-oximes: novel and highly potent antagonists for NMDA receptor glycine site. J Med Chem 1996; 39:3248-55. [PMID: 8765507 DOI: 10.1021/jm960214k] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A series of 1,2,3,4-tetrahydroquinoline-2,3,4-trione 3-oximes (QTOs) was synthesized and evaluated for antagonism of NMDA receptor glycine site. Glycine site affinity was determined using a [3H]DCKA binding assay in rat brain membranes and electrophysiologically in Xenopus oocytes expressing 1a/2C subunits of cloned rat NMDA receptors. Selected compounds were also assayed for antagonism of AMPA receptors in Xenopus oocytes expressing rat brain poly-(A)+RNA. QTOs were prepared by nitrosation of 2,4-quinolinediols. Structure-activity studies indicated that substitutions in the 5-, 6-, and 7-positions increase potency, whereas substitution in the 8-position causes a decrease in potency. Among the derivatives evaluated, 5,6,7-trichloro-QTO was the most potent antagonist with an IC50 of 7 nM in the [3H]DCKA binding assay and a Kb of 1-2 nM for NMDA receptors expressed in Xenopus oocytes. 5,6,7-Trichloro-QTO also had a Kb of 180 nM for AMPA receptors in electrophysiological assays. The SAR of QTOs was compared with the SAR of 1,4-dihydroquinoxaline-2,3-diones (QXs). For compounds with the same benzene ring substitution pattern, QTOs were generally 5-10 times more potent than the corresponding QXs. QTOs represent a new class of inhibitors of the NMDA receptor which, when appropriately substituted, are among the most potent glycine site antagonists known.
Collapse
|
39
|
[Study on effect of polysaccharides of ginseng on peripheral blood mononuclear cell induced interleukin-2 production and activity of its receptors in vitro]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 1995; 15:411-3. [PMID: 7580062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To study the effect of polysaccharides of Ginseng (PSG) on cellular-immunity from healthy subjects and patients of kidney disease, the peripheral blood mononuclear cell (PBMC) induced interleukin-2 (IL-2) were assayed in vitro. It was found that the PSG could prommote the PBMC induced IL-2 in the healthy subjects and patients with kidney diseases and was dose-dependent. This study revealed that PSG was worthwhile to be further studied as an approach of biological responsive modifier therepy in treating human immunodeficiency diseases.
Collapse
|
40
|
|
41
|
Restoration of differentiation and suppression of tumorigenicity in somatic cell hybrids of human squamous carcinoma cells and keratinocytes. CELL GROWTH & DIFFERENTIATION : THE MOLECULAR BIOLOGY JOURNAL OF THE AMERICAN ASSOCIATION FOR CANCER RESEARCH 1994; 5:1293-300. [PMID: 7696177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Somatic cell hybrid cell lines derived from the fusion of human squamous carcinoma cells (FaDu-Hyg) with human keratinocytes were used to examine the relationships between cell differentiation and tumorigenicity. Treatment of the parental keratinocytes or the two hybrid cell lines with the combination of calcium and fetal bovine serum increased the expression of the envelope precursor, involucrin, 4- to 8-fold, whereas it remained unchanged in FaDu-Hyg cells. Similarly, calcium- and serum-treated keratinocytes and the two hybrid cell lines displayed a 7- to 13-fold increase of the activity of membrane-associated type I transglutaminase, whereas transglutaminase activity in FaDu-Hyg cells did not change appreciably. FaDu-Hyg cells were tumorigenic in vivo, but tumorigenicity was suppressed in both hybrid cell lines. Analysis of additional tumor cell lines indicated that the expression of transglutaminase I and involucrin are under separate genetic control and that loss of transglutaminase activity can result either from a lack of protein or from a defect in the activation step. Thus, keratinization of squamous epithelial cells appears to be controlled by several different recessive genes, which cosegregate with but are probably only partly identical with the genes that suppress tumor formation in vivo.
Collapse
|
42
|
Abstract
Four novel isoforms of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) were found in rat aorta smooth muscle. Two of them were related to gamma-isoform of brain CaM kinase II (gamma-a). Differences in the primary structure of these isoforms were located in the variable region. One of them (gamma-b) contained 23 unique amino acid residues, whereas the other (gamma-c) did not contain this sequence. Both isoforms lacked the two segments (Val-316 to Gln-337 and Lys-353 to Leu-362) present in gamma-a. The DNA sequence of these gamma-isoforms except the variable region was exactly the same, suggesting that they are produced by alternative splicing. Another two isoforms were related to the delta-isoform of brain CaM kinase II (delta-a). delta-b contained a unique 11-residue sequence in the variable region whereas delta-c did not. As found for gamma-isoforms, the sequence analysis suggested that the three delta-isoforms are also produced by alternative splicing. Analysis of RNA by reverse transcription PCR confirmed the existence of specific messages for gamma-b, delta-a and delta-b. The variety of isoforms of CaM kinase II suggest that each isoform may play a specialized role in cell regulation.
Collapse
|
43
|
Wild-type p53 tumor suppressor gene restores differentiation of human squamous carcinoma cells but not the response to transforming growth factor beta. CELL GROWTH & DIFFERENTIATION : THE MOLECULAR BIOLOGY JOURNAL OF THE AMERICAN ASSOCIATION FOR CANCER RESEARCH 1993; 4:993-1004. [PMID: 8117626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In order to clarify the role of the p53 tumor suppressor gene in controlling growth and differentiation of human epithelial cells, we transfected a wild-type p53 complementary DNA, driven by a dexamethasone-inducible mouse mammary tumor virus promoter, into SqCC/Y1 human head-and-neck squamous carcinoma cells. When treated with dexamethasone, 2 of 8 independent clones that contained integrated vector sequences expressed wild-type p53-specific mRNA as well as nuclear p53 protein. The highest p53 expressor (SqCC/Y1.53.5) was as resistant to inhibition of cell growth by transforming growth factor beta as control transfectants. Furthermore, these cells continued to proliferate in medium containing the combination of 2 mM Ca2+ and 10% (v/v) fetal bovine serum, which normally induces terminal differentiation in primary keratinocytes. However, under these same conditions, two of the essential proteins required for the formation of the cornified cell envelope were induced. First, in SqCC/Y1.53.1 and -.5 cells, the activity of membrane-associated keratinocyte-specific transglutaminase I increased to 3- to 5-fold higher levels than in control transfectants. Second, in SqCC/Y1.53.1 and -.5 cells, the envelope precursor, involucrin, increased to 5 to 8 times the levels attained in control transfectants. Thus, reexpression of wild-type p53 does not restore responsiveness of SqCC/Y1 carcinoma cells to growth inhibition but allows cells to reexpress the proteins required for the assembly of the cornified cell envelope.
Collapse
|
44
|
[Advances in perinatology]. ZHONGHUA YI XUE ZA ZHI 1993; 73:728-30. [PMID: 8143179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
|
45
|
Characterization of three new triterpenoid saponins from Ardisia japonica. JOURNAL OF NATURAL PRODUCTS 1993; 56:1669-1675. [PMID: 8277306 DOI: 10.1021/np50100a002] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The isolation and characterization of three novel triterpene glycosides 1-3 from the medicinal plant Ardisia japonica (Myrsinaceae) are described. The compounds are characterized by a branched oligosaccharide chain, composed of four sugar units. The oligosaccharide structures were determined by 1H-1H correlation spectroscopy (COSY, HOHAHA, ROESY) and 1H-13C heteronuclear correlation (HETCOR) nmr experiments. The aglycone moieties are the oleane-type triterpenes cyclamiretin A for 1 and the new 13,28-epoxy-30,30-dimethoxyolean-3 beta, 16 alpha-diol and 3 beta, 16 alpha-dihydroxy-13,28-epoxyolean-29-oic acid for 2 and 3, respectively.
Collapse
|
46
|
Resistance of human squamous carcinoma cells to transforming growth factor beta 1 is a recessive trait. Proc Natl Acad Sci U S A 1993; 90:6280-4. [PMID: 8327510 PMCID: PMC46912 DOI: 10.1073/pnas.90.13.6280] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Because most human squamous carcinoma cell lines of the aerodigestive and genital tracts are refractory to the antiproliferative action of transforming growth factor beta 1 (TGF beta 1) in vitro, we have begun to identify the causes for resistance of squamous carcinoma cell lines to TGF beta 1 by using somatic cell genetics. Two stable hybrid cell lines (FaDu-HKc.1 and FaDu-HKc.2) were obtained by fusing a TGF beta 1-resistant human squamous carcinoma cell line, FaDu-HygR, with a human papilloma virus 16-immortalized, TGF beta 1-sensitive, human foreskin keratinocyte cell line, HKc-neoR. Whereas TGF beta 1 did not inhibit DNA synthesis in parental FaDu-HygR cells, it reduced DNA synthetic activity of HKc-neoR, FaDu-HKc.1, and FaDu-HKc.2 cells by 75-85% (IC50, 2-5 pM). Although squamous carcinoma cells express lower than normal levels of TGF beta 1 type II receptors on their cell surface, TGF beta 1 type II receptor mRNA was detected in all four cell lines. Recessive genes involved in TGF beta 1 signaling may be localized to the distal portion of chromosome 18q, as this was the sole chromosomal region of homozygous deletion in parental FaDu-HygR cells. Furthermore, our previous observation that mutant p53 decreases sensitivity of keratinocytes to TGF beta 1 was supported by the finding that the level of the mutant p53 protein expressed by the hybrid cell lines was greatly reduced. In summary, TGF beta 1 resistance of FaDu cells appears to be recessive and is presumably due to the loss of one or more post-receptor elements of the signaling pathway.
Collapse
|
47
|
[Isolation and identification of alkaloids from Fritillaria egregia Y.K. Yang, J.Z. Wu et D.T]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1993; 18:228-30, 255. [PMID: 8216790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
|
48
|
Mutant p53 tumor suppressor gene causes resistance to transforming growth factor beta 1 in murine keratinocytes. Cancer Res 1993; 53:899-904. [PMID: 8094035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Human carcinoma cell lines are frequently refractory to the antiproliferative effect of the autocrine growth inhibitor transforming growth factor beta 1 (TGF-beta 1) and often express mutant forms of the tumor suppressor gene p53. Therefore, we wished to determine whether mutant p53 affects the cellular response to TGF-beta 1. A murine p53 complementary DNA carrying an activating point mutation was introduced into TGF-beta 1-sensitive BALB/MK mouse epidermal keratinocytes by retroviral infection. Mp53 transformed cells displayed a spindle-type morphology and expressed between 0.02 and 0.7 ng of mutant p53/mg total protein. Furthermore, whereas TGF-beta 1 caused approximately 90% maximal inhibition of DNA synthesis of parental BALB/MK cells, the Mp53 transformants were inhibited by less than 70%. The median inhibiting dose of TGF-beta 1 was 4.07 +/- 1 (SE) pM for BALB/MK cells, but ranged from 2.4 to 11.2 pM and from 11.7 to 40 pM for two different sets of Mp53 transformants, and increased as a function of the amounts of mutant p53 protein that were expressed. Our findings suggest that mutant forms of p53 inhibit the antiproliferative effect of TGF-beta 1 by interfering with its signaling pathway.
Collapse
|
49
|
Measurement of spin observables using a storage ring with polarized beam and polarized internal gas target. PHYSICAL REVIEW LETTERS 1993; 70:738-741. [PMID: 10054191 DOI: 10.1103/physrevlett.70.738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
|
50
|
Activation of the autocrine transforming growth factor alpha pathway in human squamous carcinoma cells. Cancer Res 1991; 51:6254-62. [PMID: 1933886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Transforming growth factor alpha is an autocrine mitogen for nonneoplastic keratinocytes, which exerts its function by binding to the receptor for epidermal growth factor. In order to determine whether this autocrine pathway is activated in squamous carcinoma cells, we analyzed the production of transforming growth factor alpha as well as the expression and regulation of epidermal growth factor receptors in a panel of human squamous carcinoma cell lines. Immunoreactive transforming growth factor alpha was detectable in squamous carcinoma cells as well as in quiescent nonneoplastic keratinocytes. However, in the absence of exogenous mitogens, only the squamous carcinoma cells secreted the growth factor into the medium, whereas untransformed keratinocytes did not. Each of the squamous carcinoma cell lines expressed significantly greater numbers of cell surface epidermal growth factor receptors than normal keratinocytes. The epidermal growth factor receptor gene was amplified and overexpressed in three of the squamous carcinoma cell lines (A431, CaSki, SqCC/Y1). Two of the squamous carcinoma cell lines (C4-1 and CE-48) displayed a relative inability to down-regulate epidermal growth factor receptors in response to epidermal growth factor. The mechanism of receptor overexpression in the remaining three cell lines (A253, CaLu-1, FaDu) is unexplained. Thus, human squamous carcinoma cell lines frequently exhibit a combination of the constitutive secretion of transforming growth factor alpha and the overexpression of epidermal growth factor receptors. Treatment of these tumor cells with an antibody directed against the ligand-binding domain of the epidermal growth factor receptor inhibited their growth by approximately 50%. These findings suggest that designing strategies to interrupt the transforming growth factor alpha autocrine pathway might lead to new modalities to treat this class of malignant tumors.
Collapse
|