Downregulation of oxytocin receptors in right ventricle of rats with monocrotaline-induced pulmonary hypertension

AIM

pulmonary hypertension (PH) in the rat leads to right ventricular (RV) hypertrophy, inflammation and increased natriuretic peptide (NP) levels in plasma and RV. Because the release of nitric oxide (NO) and atrial natriuretic peptide (ANP) is a function of the oxytocin receptor (OTR), we examined the effect of PH on gene and protein expression of OTR, NP (A, atrial; B, brain) and receptors (NPRs), nitric oxide synthases (NOS), interleukin (IL)-1β, IL-6 and tumour necrosis factor-α in the hypertrophied RV in a model of PH.

METHODS

RV hypertrophy was induced in male Sprague-Dawley rats with monocrotaline (MCT; 60 mg kg(-1) ) and was confirmed by the presence of an increased RV weight and RV-to-[left ventricle (LV) and septum] ratio.

RESULTS

in the RV of MCT-treated rats, a approximately 40% reduction in OTR mRNA and protein was observed compared with the RV of control rats. This reduction was associated with increased transcripts of ANP and BNP in both ventricles and a corresponding increase in NP receptor mRNA expression for receptors A, B and C. Protein expression of inducible NOS was increased in the RV, whereas endothelial NOS transcripts were increased only in the LV of MCT-treated rats. In the RV of MCT-treated rats, downregulation of OTR was also associated with increased mRNA expression of IL-1β and IL-6.

CONCLUSION

our results show that downregulation of the OTR in the RV of MCT-treated rats is associated with increased expression of NP and their receptors as well as IL-1β and IL-6. This reduction in OTR in RV myocardium may have an impact on cardiac function in the MCT-induced model of PH.

Diurnal variations in solar ultraviolet radiation on horizontal and vertical plane

BACKGROUND

In general, measurements of solar ultraviolet (UV) radiation are related to horizontal surfaces. While the humans walking and standing outdoors expose to the natural solar UV radiation, their eyes, cheeks, extremities, trunks, or many other anatomical sites are close to vertical plane and random orient to different directions. In this study, we characterized the diurnal variations in solar UV on horizontal and vertical plane which may be helpful to obtain more relevant information on UV exposure of humans.

METHODS

The UV exposure on vertical and horizontal plane were measured using Solar-UV Sensors in Shenyang (41°51″N, 123°27″E) and Sanya (18°19'N, 109°42'E), PR China.

RESULTS

As the well known, the diurnal variations in solar UV on horizontal plane in a sunny day exhibited unimodal distributions, reached a single UV peak exposure at around solar noon. However, the diurnal variations on vertical plane presented bimodal distributions, with two peaks in summer in Shenyang and Sanya, and a unimodal distribution in winter in Shenyang. In spring and autumn in Shenyang, the UV exposure around noon were slightly flat with no significant peaks but relative high. When the Solar Elevation Angle (SEA) is about 40°, the vertical plane may potentially receiving maximal unweighted total solar UV radiation exposures.

CONCLUSION

The results potentially showed that the protection of some vertical and near-vertical anatomical sites of human body from high UV exposure should not only focused on the periods of before and after noon especially in high SEA places.

Clinical analysis of elderly patients with elderly-onset type 2 diabetes mellitus in China: assessment of appropriate therapy

Patients with elderly-onset diabetes have specific characteristics. This study was designed to investigate these characteristics and to evaluate methods for appropriate control of glycaemia and cardiovascular risk factors in elderly-onset diabetes patients. A total of 155 elderly patients with type 2 diabetes mellitus were divided into those diagnosed at >or= 65 years of age (elderly-onset group, 75 patients) and those diagnosed at < 60 years of age (usual-onset group, 80 patients). Differences in clinical variables, diabetic complications, diagnosed comorbidities and the use of medications were analysed. Mean glycosylated haemoglobin, fasting plasma glucose and fasting insulin levels were significantly lower in the elderly-onset group than in the usual-onset group. The usual-onset group showed significantly greater homeostasis model assessment insulin resistance than the elderly-onset group. Microvascular complications and insulin use were significantly more common in the usual-onset group. In conclusion, insulin resistance was less severe in elderly-onset diabetes than in usual-onset diabetes. As hyperglycaemia was relatively mild or moderate, oral hypoglycaemic agents might be effective for elderly-onset diabetes.

Screen of micro-organisms for inducing the production of dragon's blood by leaf of Dracaena cochinchinensis

AIMS

To screen micro-organisms for inducing the production of dragon's blood, which is normally produced by stem xylem and by leaf of Dracaena cochinchinensis, and to evaluate the product by comparing with the standard.

METHODS AND RESULTS

Thirty microbial strains were isolated from D. cochinchinensis leaves. Three of them were confirmed to elicit the leaf of D. cochinchinensis producing dragon's blood after inoculation. Upon elicitation, all of the 6-month-old leaves of the inducible trees produced dragon's blood; 60-70% of the 1-year-old leaves elicited produced the resin. All the three strains were identified as Colletotrichum gloeosporioide by morphological and molecular methods. The leaf resin had a similar TLC profile and antioxidant activities to the standard resin. In particular, it had a higher total flavonol content and antimicrobial activity than the standard.

CONCLUSIONS

Upon the induction of the screened C. gloeosporioide mycelia, D. cochinchinensis leaf produced dragon's blood with higher total flavone content and antimicrobial activity than the standard dragon's blood.

SIGNIFICANCE AND IMPACT OF THE STUDY

This work has provided a strategy for producing dragon's blood in a sustainable way using leaves of C. gloeosporioides by fungal elicitation.

Treatment with peginterferon versus interferon in Chinese patients with chronic hepatitis C

Higher sustained virological response (SVR) rates after treating with peginterferon than after treating with interferon have been obtained in some randomized clinical trials (RCTs) in Chinese patients with chronic hepatitis C (CHC). However, the numbers of patients included in these clinical trials were too small to draw a clear conclusion. Therefore, a new meta-analysis including a large number of patients was needed to compare peginterferon with interferon in the treatment of Chinese CHC patients. A search of Medline, the China National Knowledge Infrastructure, the Wanfang Database, and the China Biomedical Database for relevant articles published between 1966 and 2009 was performed. RCTs comparing the use of peginterferon and interferon for the treatment of Chinese patients with CHC were assessed. Of the 236 studies screened, 18 RCTs including 1,148 patients (659 treated with peginterferon therapy and 489 treated with interferon therapy) were analyzed. The total SVR rates obtained in patients treated with peginterferon were significantly higher than those obtained in patients treated with interferon (64% vs. 40%; relative risk, 1.56; 95% confidence interval: 1.28-1.91; p < 0.01), but the difference between the peginterferon α-2b and interferon α-2b treatments was not significant. Withdrawal rates were similar between patients treated with peginterferon and interferon. Chinese patients with CHC have a greater likelihood of achieving an SVR with peginterferon α-2a.

Genetic diversity and origin of Gayal and cattle in Yunnan revealed by mtDNA control region and SRY gene sequence variation

There are hump, humpless cattle and gayal distributed in Yunnan province, south-west China, but their genetic background remains unclear. To determine the origin and genetic diversity of Yunnan gayal and cattle (Diqing, Nujiang and Wenshan cattle), we analysed mtDNA control region sequences of 71 samples and SRY gene sequences of 39 samples, together with the available sequences in GenBank. The neighbour-joining phylogeny and the reduced median network analysis showed that Yunnan gayal originated from the hybridization between male Bos frontalis and female Bos taurus or Bos indicus, and that Yunnan cattle mostly originated from B. indicus, also containing some hybrids of male B. indicus and female B. taurus. The phylogenetic pattern of Yunnan cattle was consistent with the recently described cattle matrilineal pool from China and indicated more contribution to the Yunnan cattle from B. indicus than from B. taurus.

Nutrient composition and degradation profiles of anthocyanidin-accumulating Lc-alfalfa populations

Alfalfa (Medicago sativa L.) is one of the most used forages in the world but suffers the disadvantage of having poor protein utilization by the animal. The poor protein utilization is the result of excessive ruminal protein degradation, which might be reduced by the protein precipitating capacity of anthocyanidin (AC) and condensed tannins (CT). The objective of this study was to determine the effects of the Lc-transgene on survival, anthocyanidin, condensed tannin and chemical profiles in crossed populations of western Canadian-adapted Lc-alfalfa. These were compared with their non-transgenic (NT) parental varieties, Rangelander, Rambler, and Beaver. Lc-alfalfa forage accumulated enhanced amounts of anthocyanidin, with an average concentration of 197.4 µg g-1 DM, while condensed tannins were not detected. Both of these metabolites were absent in the NT parental varieties. Lc-alfalfa had a lower (24.8 vs. 27.3% DM; P < 0.02) crude protein (CP) and higher (58.3 vs. 55.5% DM; P < 0.01) carbohydrate (CHO) concentration, which resulted in their decreased (P < 0.01) N:CHO ratio (68.1 vs. 79.2 g kg-1) compared with NT alfalfa. Slowly degradable N:CHO ratio was decreased by 5.9 g kg-1 (P < 0.03) and total rumen-degradable N:CHO ratio was decreased by 12.9 g kg-1 (P < 0.03) in Lc-alfalfa compared with NT alfalfa. In conclusion, Lc-gene transformation resulted in the accumulation of anthocyanidin, decreased total protein content, increased total carbohydrate content and improved the balance between nitrogen and carbohydrates in the crossed transgenic populations of western Canadian-adapted alfalfa compared to their NT western Canadian parental alfalfa varieties. Key words: Alfalfa, anthocyanidin, Lc-transgene, protein and carbohydrate sub-fractions, nitrogen-to-carbohydrate degradation ratios

Seasonal changes in antifreeze protein gene transcription and water content of beetle Microdera punctipennis (Coleoptera, Tenebrionidae) from Gurbantonggut desert in Central Asia

Desert beetle Microdera punctipennis (Coleoptera: Tenebriondae) is a special species in Gurbantonggut Desert in Central Asia. To investigate the possible strategy it employs for cold survival, seasonal changes in supercooling point (SCP), body water content, haemolymph osmolality and antifreeze protein gene (Mpafp) expression were measured over 13 months. Our results show SCPs in M. punctipennis adults changed from -8.0°C in summer to -18.7°C in winter. During winter, adults endured modest water loss; total water decreased from 65.4 percent in summer to 55.9% in winter. Mpafp mRNAs level increased by 13.1 fold from summer to early winter, and haemolymph osmolality increased accordingly from 550 mOsm to 1486 mOsm. Correlation coefficient of Mpafp mRNAs level and SCP indicates that Mpafp mRNA explained 65.3 percent of the variation in SCPs. The correlation between Mpafp mRNA level and total water reflected an indirect influence of antifreeze protein on water content via reducing SCP.