Association of Left Anterior Descending Coronary Artery Calcium Progression and Radiation Dose with Major Adverse Cardiac Events in Breast Cancer

PURPOSE/OBJECTIVE(S)

Coronary artery calcium (CAC) is associated with increased risk of major adverse cardiac events (MACE). Accelerated CAC progression has been observed in patients with breast cancer after radiotherapy (RT) and there is a relationship between left anterior descending (LAD) coronary artery RT dose and the risk of coronary events. However, there is lack of consensus on LAD dose constraints for breast RT and limited data on the extent and impact of CAC progression. Our objective was to evaluate the association of LAD dose exposure and CAC progression with the risk of MACE in patients with breast cancer following RT.

MATERIALS/METHODS

Retrospective analysis of 181 patients with breast cancer treated with RT between 2008 and 2019. CAC was manually measured on RT planning and follow-up CTs (with at least one-year interval) using the Agatston method. Coronary arteries were segmented using a deep learning-based automated algorithm and dosimetric parameters collected. MACE cumulative incidence was estimated, and Fine and Gray regressions performed, accounting for non-cardiac death as a competing risk.

RESULTS

The median follow-up following RT was 70 months (interquartile range [IQR], 53-86). The median age was 63 years (IQR, 53-72), 43% had hypertension, 40% hyperlipidemia, 8% coronary heart disease (CHD). Most had pathologic stage I-II disease (76%). RT was targeted to breast/chest wall only in 60% and included regional nodes in 40% (internal mammary chain in 4%). The most common dose/fractionation was 48-50.4 Gy/25-28 fractions (67%) and 42.6-42.7 Gy/16 fractions (30%). At the time of RT, 68 (38%) had at least moderate CAC burden (CAC >100; statin-therapy indicated), but only 29 (43%) were on statin therapy. At a median interval of 44 months (IQR, 26-63), 55% (n = 84) had CAC progression, with a median increase of 52%/year (IQR, 18-193). The median time to MACE was 68 months (IQR, 53-85), with a 5-year cumulative incidence of 7.3% (15 MACE overall). Accounting for age and CHD, there was an increased risk of MACE with LAD CAC progression (subdistribution hazard ratio [SHR] 1.02/10 CAC points; 95% confidence interval [CI] 1.01 = 1.03; p = .007) and the volume of LAD receiving 15 Gy (LAD V15 Gy; SHR 1.03/%; 95% CI, 1.01-1.06; p = .004). There was no association between mean heart dose, chemotherapy, or Her2 therapy exposure and MACE (p>.05).

CONCLUSION

LAD CAC progression and LAD V15 Gy dose exposure were associated with an increased risk of MACE following RT. Accelerated CAC progression was commonly observed, however most patients were under-optimized for cardiovascular (CV) risk, with less than half of statin-eligible patients with at least moderate CAC burden on statin therapy. Together, these data support more aggressive cardiac risk mitigation approaches, including guidelines-based CV risk factor modification and optimized sparing of LAD radiation dose.

First Report of Black Spot Disease Caused by Alternaria alternata on Persimmon Fruit in China

Sweet persimmon is native to Japan and valued for its fruit, which are high in sugar and vitamins. In October 2021, symptoms were observed on persimmon (Diospyros kaki L. cv. Yangfeng) fruits in cold storage room in Suiping county, Henan Province (32.59 °N, 15 113.37 °E). Initially, small circular dark-brown spots were visible on the fruit rind, turning into irregular sunken dark areas, and eventually rotting 15% of 200 fruits after four weeks of cold storage (10°C, 95% relative humidity). To isolate the causal agent, 10 fruits of symptomatic tissues (4 mm²) were surface-sterilized in 2% sodium hypochlorite (NaOCl) for 1 minute, washed three times in sterile distilled water, then aseptically transferred to potato dextrose agar (PDA) and incubated for 7 days at 25°C. Fungal colonies were isolated from plant tissue, and on three colonies of similar morphology, single-spore isolation was performed. On PDA, the isolates produced circular colonies of fluffy aerial mycelia, gray-brown in the center with gray-white margins. Conidia were dark brown, obclavate or pyriform, with 0 to 3 longitudinal septa and 1 to 5 transverse septa, and a size range of 19.2 - 35.1 × 7.9 - 14.6 μm (n=100). Conidiophores were olivaceous, septate, straight, or bent, with a length of 18 - 60 × 1 - 3 μm (n=100). These morphological characteristics identify the isolates as Alternaria alternata (Simmons. 2007). Genomic DNA was extracted from a representative isolate YX and re-isolated strain Re-YX by cetyltrimethylammonium bromide (CTAB). The primers of ITS1/4, Alt-F/R, GPD-F/R, EF1/2, EPG-F/R (Chen et al. 2022), RPB2-5F/7cR (Liu et al. 1999), and H3-1a/1b (Lousie et al. 1995) were used to amplify the partial internal transcribed spacer (ITS) region, Alternaria major allergen (Alt a1), Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), translation elongation factor 1-alpha (TEF), endo-polygalacturonase (endoPG), RNA polymerase second largest subunit (RPB2) and Histone 3 (His3), respectively. GenBank accession No of ITS, Alt a1, GAPDH, TEF, endoPG, RPB2, His3 were ON182066, ON160008 to ON160013 for YX and OP559163, OP575313 to OP575318 for Re-YX respectively. Sequence data of Alternaria spp. were downloaded from GenBank and the BLAST analysis showed 99%-100% homology between various A. alternata strains (ITS: MT498268; Alt a1: MF381763; GAPDH: KY814638; TEF: MW981281; endoPG: KJ146866; RPB2: MN649031; His3: MH824346). A phylogenetic analysis based on ITS, Alt a1, GAPDH, TEF, and RPB2 sequences using MEGA7 (Molecular Evolutionary Genetics Analysis) revealed that the isolate YX and Re-YX were clustered in A. alternata clade (Demers M. 2022). For the pathogenicity test, seven-day-old cultures were used to create spores suspensions (5.0 × 105 spores/mL) of each of the three isolates. Ten µL aliquots from each isolate were inoculated onto ten needle-wounded persimmon fruits; ten additional fruits were inoculated with water only to serve as controls. The pathogenicity test was three replications. Fruits were deposited in a climate box at 25°C, 95% relative humidity. Seven days post-inoculation, the wounded fruit treated with spore suspensions displayed black spot symptoms similar to the symptoms on the original fruit. There were no symptoms on the control fruits. The strain Re-YX was re-isolated from the symptomatic tissue of inoculated fruits and its identity confirmed using the morphological and molecular methods previously mentioned, fulfilling Koch's postulates. The persimmon fruit rot caused by A. alternata had been reported in Turkey and Spain (Kurt et al., 2010, Palou et al., 2012). According to our knowledge, this is the first report of black spot disease on persimmon fruits caused by A. alternata in China. The disease could infect persimmon fruits during cold storage, so more control methods should be developed to prevent postharvest disease of persimmon in the future.

First Report of Fruit Rot Caused by Fusarium graminearum on Ponkan (Citrus reticulata Blanco cv. Ponkan) in China

Ponkan (Citrus reticulata Blanco cv. Ponkan) is a Chinese citrus species with tasty fruit. In November 2021, an unknown postharvest disease of Ponkan fruit caused nearly 15% losses of 2000 fruits in Nanchang, Jiangxi Province (28.68° N, 115.85° E). The initial fruit's surface necrosis was brown (Xu et al. 2022) (Figure 1A). Disease spots spread to the entire fruit, white or grey hyphae appeared, and the fruit rotted. Twenty diseased fruits were surface-disinfested with 2% sodium hypochlorite and 75% ethanol, then rinsed with sterile distilled water to isolate the pathogen. Diseased tissue sections (5 × 3 mm) were incubated on potato dextrose agar (PDA) for 7 days at 25°C. Twelve of 15 monoconidial isolates have similar morphology. On PDA, the isolates produced copious white aerial mycelia. After 5-7 days on straw juice medium, two types of conidia appeared (Rice straw 60 g, Agar 20 g, distilled water 1000 mL) (Figure 1E-I). Macroconidia were abundant, falcate, slender, and slightly curved with 0-8 septa, mostly 4-5 septa (average 41.70 × 3.81 m, n=100) (Figure 1J). Microconidia were globose, oval, or piriform with 0-1 septa, 2.72 to 8.57 × 2.53 to 7.47 m (average 5.49 × 4.52 m, n=50) (Figure 1L), and chlamydospores were not observed. Conidial and colony morphology identified 12 monoconidial isolates as Fusarium graminearum (Fisher et al., 1982; Yulfo-Soto et al., 2021). Genomic DNA was extracted from three isolates using a DNA Extraction Kit (Yeasen, Shanghai, China). The ITS1/4 region combined with partial gene fragments of translation elongation factor-1 alpha (TEF-1α, primer TEF1/2, O'Donnell et al. 1998), RNA polymerase second largest subunit (RPB2, primer fRPB2-5F/7cR, Liu et al. 1999) and β-tubulin (β-tub, primer Bt2a/2b, Li et al. 2013) from the isolates were amplified and sequenced. The three tested isolates showed identical gene sequences. Sequences amplified from one representative isolate (PG16) have been submitted to GenBank. BLAST searches revealed that ITS (OM019317), TEF-1α (OM048103), RPB2 (ON364348), and β-tub (OM048104) had 99 to 100% identity compared with F. graminearum (MH591453.1, KX087136.1, MF662636.1, and MZ078952.1, respectively) in GenBank. The phylogenetic analysis combined ITS - TEF-1α - RPB2 (O'Donnell et al. 2015) concatenated sequences using MEGA7.0 (Mao et al. 2021) showed the isolate was clustered with the F. graminearum clade with 100% bootstrap support (Figure 2). The isolate PG16 was used for pathogenicity tests. Ponkan fruits were surface-disinfested with 75% ethanol and rinsed with sterile distilled water three times. Then, 30 punctured wound fruits (2-mm-diameter, 2-mm-depth) with a sterile needle and 30 unwounded fruits were inoculated with conidial suspension (10 µL, 3.0 × 105 conidia/mL). while the control fruits were inoculated with 10 µL sterile distilled water. All fruits were incubated at 25°C and 90% relative humidity. Two days later, all wounded fruits inoculated with conidial suspension showed disease spots, similar symptoms to the original rotten fruits (Figure 1D). Control and conidial-inoculated unwounded fruits were healthy (Figure 1B-C). The Pathogenicity test was repeated twice, and similar symptoms were observed. Morphologically and molecularly, the re-isolated fungus matched the inoculated isolate. First report of F. graminearum causing Ponkan fruit rot in China. As Ponkan is an important citrus crop with high economic value in China, identification of the causing agent, F. graminearum, for fruit rot allows the development of control measures to manage this disease.

First Report of Leaf Spot Disease on Chamaedorea elegans Caused by Fusarium oxysporum in China

Chamaedorea elegans, native to Mexico and Guatemala, is a commonly planted indoor and small-scale garden ornamental due to its stately appearance, tolerance of low light levels, and its ability to improve air quality (El-Khateeb et al. 2010). In December 2021, an unknow leaf-spot disease was observed on C. elegans in Ganzhou City of Jiangxi Province, China (25.83 °N, 114.93 °E). The symptoms were small brown spots on the leaves, gradually expanded into irregular dark brown spots with necrotic tissue forming in the center of the lesions (Figure 2 A-1 and A-2). To isolate the pathogen, the diseased leaves were surface sterilized in 75% ethanol for 30 s. Small pieces of tissue (5 × 5 mm) were taken from the margin between diseased and healthy tissue, disinfected 1% NaClO for 45 s, washed three times in sterile water, and then placed on PDA at 25 ± 1°C for 5 days. Later, five isolates were purified from single spores and each of the five isolates has the same properties as described below. The isolates had abundant pale purple flocculent hyphae with purple pigmentation (Figure 2 C-1 and C-2). Macroconidia were falciform, straight or slightly curved, 1-2 septate, 11.75 to 22.99 × 3.06 to 4.44 μm (μ=16.08 μm × 3.37 μm, n=50) (Figure 2 D-1). Microconidia were oval or elliptical, a septate, 4.03 to 9.19 × 1.92 to 3.73 μm (μ=5.88 μm × 2.66 μm, n=50) (Figure 2 D-2). Chlamydospores formed singly or in pairs, and were terminal or intercalary in hyphae (Figure 2 D-3). Based on morphological characteristics, the fungus was preliminarily identified as a Fusarium sp. (Leslie et al. 2006). To confirm the identification, primers ITS1/ITS4 (White et al. 1990), RPB2-5f2/RPB2-7cr (O'Donnell et al. 2010; Liu et al. 1999) and TEF 1-αF/TEF 1-αR (O'Donnell et al. 2000) were used to amplify and sequence apportion of the ITS, RPB2 and TEF (Table 1). The sequences (Genebank accession number: OM780148, OM782679, OM782680) shared 100% idnetity with Fusarium oxysporum (Genebank accession number: MH866024.1, MH484930.1, MH485021.1). The maximum likelihood (ML) phylogenetic analysis of the concantenated ITS, RPB2 and TEF sequences was performed in MEGA7.0. (Sudhir et al. 2016), assigning the isoaltes to the F. oxysporum species complex (Figure 1). To confirm the pathogenicity, nine pots of healthy 3-year-old C. elegans plants were inoculated in the greenhouse (12 h light/12 h dark cycle, RH 90 %, three for wounded inoculation, three for nonwounded inoculation and three for control). Fifty disinfected leaves were wounded with sterile needles and fifty remained unwounded. The wounded (Figure 2 B-1 and B-2) and unwounded leaves were inoculated with a 10 μL spore suspension (1.0 × 106 conidia/ml) which was taken from each of the five isolates cultured for 7 days. Fifty leaves were mock-inoculated with sterile water (Figure 2 B-3 and B-4). After incubation for 7 days, the wounded leaves inoculated with the spore suspension had similar symptoms to the original diseased leaves, while the unwounded leaves and the control leaves did not develop symptoms. The experiment was repeated three times and the pathogens was reisolated from wound-inoculated leaves with the same morphological characteristics to the original pathogens, and identified as F. oxysporum by morphological and molecular analysis, completing Koch's postulates. F. oxysporum, a pathogen with a broad spectrum of hosts, ranks 5th among the top 10 fungal plant pathogens (Amjad et al. 2018.) and has been reported to Carpinus betulus, Citrullus lanatus, Pinus pinea (Mao et al. 2021; Muhammad et al. 2021; Monther et al. 2021). To our knowledge, this is the first report of leaf spot disease on C. elegans caused by F. oxysporum in China. C. elegans is an important ornamental plant in China with high economic value, so the disease has the potential to be a threat to its cultivation industry.

The Anti-Constipation Effects of Raffino-Oligosaccharide on Gut Function in Mice Using Neurotransmitter Analyses, 16S rRNA Sequencing and Targeted Screening

Raffino-oligosaccharide (ROS), the smallest oligosaccharide of the raffinose family, is a novel food ingredient. However, the anti-constipation effects of ROS remain obscure. This study investigates the anti-constipation effects of ROS based on the loperamide-induced mice model and reveals the underlying mechanism using constipation parameters, neurotransmitter level, 16S rRNA sequencing, and the targeted screening strategy. The prevention effects were firstly investigated by the gastro-intestinal transit rate experiment (50 mice) and defecation status experiment (50 mice), which were divided into five groups (n = 10/group): blank, model, and low-, medium- and high-dose ROS. Furthermore, the slow-transit constipation experiment (blank, model, and high-dose ROS, n = 10/group) was conducted to illustrate the underlying mechanism. The results showed that ROS aided in preventing the occurrence of constipation by improving the gastro-intestinal transit rate and the defecation frequency in mice, and ROS significantly reduced the serum levels of vasoactive intestinal peptide (VIP). In addition, ROS regulated the diversity and structure of intestinal flora. Among them, one specific family and six specific genera were significantly regulated in constipated mice. The targeted screening revealed that 29 targets related to the anti-constipation effects of ROS, indicating ROS may play a role by regulating multiple targets. Furthermore, the network pharmacology analysis showed that Akt1, Stat3, Mapk8, Hsp90aa1, Cat, Alb, Icam1, Sod2, and Gsk3b can be regarded as the core anti-constipation targets. In conclusion, ROS could effectively relieve constipation, possibly by inhibiting the level of neurotransmitters and regulating the gut flora in mice. This study also provides a novel network pharmacology-based targeted screening strategy to reveal the anti-constipation effects of ROS.

Protective effect of hawthorn extract against genotoxicity induced by benzo(<alpha>)pyrene in C57BL/6 mice

Benzo(<alpha>)pyrene [B(<alpha>)P], widely originated from environmental pollution or food process such as roasting and frying, is a strong mutagen and potent carcinogen. Utilization of hawthorn has been reported against physical mutagens. Our study found that hawthorn extract (HE) contained abundant phenolic compounds, wherein chlorogenic acid was 2.78 mg/g, procyanidine B2 was 3.58 mg/g, epicatechin was 2.99 mg/g DW, which may contribute to anti-genotoxicity activity. So, the role of HE against B(<alpha>)P-induced genotoxicity in C57BL/6 mice was further assessed. Fifty mice were distributed into five groups: control group, B(<alpha>)P group (30 mg/kg, i.p.), B(<alpha>)P + HE-L group (100 mg/kg, i.g.), B(<alpha>)P + HE-M group (200 mg/kg, i.g.), B(<alpha>)P + HE-H group (400 mg/kg, i.g.). Mice were orally administered with solutions of HE for 10 days and injected intraperitoneally with B(<alpha>)P for 3 days from the 8th day. Results showed that B(<alpha>)P can induce significantly pathological damage in liver, lung and spleen, as well as decrease white blood cells (WBCs). Remarkably elevated levels of reactive oxygen species (ROS), DNA strand breaks (DSBs) and G1 cell cycle arrest were also found in B(<alpha>)P group, with upregulated expressions of p-H2AX, p-p53 and p21 in bone marrow cells. With administration of HE, liver, lung and spleen injury significantly mitigated, while WBCs were evidently increased in B(<alpha>)P-treated mice. Consistently, HE markedly reduced level of ROS, DSBs and G1 cell cycle arrest accompanied by reducing expressions of p-H2AX, p-p53 and p21 in bone marrow cells. Combined, these results indicated a protective role of HE on B(<alpha>)P-induced genotoxicity.

Euglycemic progression: worsening of diabetic retinopathy in poorly controlled type 2 diabetes in minorities

AIMS

In type 2 diabetes, early effects of strict near-normalization of glucose control on macrovascular and microvascular disease are still uncertain. We evaluated the effects of early dramatic improvement in glycemia on retinal disease in poorly controlled diabetes.

METHODS

A retrospective, case-control study in public hospital patients with type 2 diabetes, who had annual retinal imaging as part of a case management program or standard diabetes care. Patients included had ≥2 two retinal images ≥1 one year apart, and at least 3 HbA1C measurements. Retinal images were graded using a modified Scottish Diabetic Retinopathy grading scheme. An 'intensive' group (n=34) with HbA1C decrease >1.5% was compared with randomly chosen patients (n=34) with minimal HbA1C changes.

RESULTS

Mean HbA1C (±SEM) over two years was similar in intensive (8.5 ± 0.21%) and control groups (8.1 ± 0.28%, p=NS). However, the intensive group had higher baseline HbA1C and a mean maximal decrease of 4.0 ± 0.41% in contrast to the control group (0.2 ± 0.11%). Retinopathy grade progressed +0.7 ± 0.25 units from baseline in the intensive group (p=0.015), a 22.6% worsening. The control group changed minimally from baseline (0.03 ± 0.14 units, p=NS). Change in retinopathy grade was significantly different between groups (p=0.02). More eyes worsened by ≥ 1 retinal grade (p=0.0025) and developed sight-threatening retinopathy (p=0.003) in the intensive group. Visual acuity was unchanged.

CONCLUSIONS

Diabetic retinopathy significantly worsened in poorly controlled type 2 diabetes after early intensification of glycemic control and dramatic HbA1C change. Retinal status should be part of risk-factor evaluation in patients likely to experience marked reductions in HbA1C in poorly controlled diabetes.

Epilepsy surgery trends in the United States, 1990-2008

OBJECTIVE

To examine national time trends of resective surgery for the treatment of medically refractory epilepsy before and after Class I evidence demonstrating its efficacy and subsequent practice guidelines recommending early surgical evaluation.

METHODS

We performed a population-based cohort study with time trends of patients admitted to US hospitals for medically refractory focal epilepsy between 1990 and 2008 who did or did not undergo lobectomy, as reported in the Nationwide Inpatient Sample.

RESULTS

Weighted data revealed 112,026 hospitalizations for medically refractory focal epilepsy and 6,653 resective surgeries (lobectomies and partial lobectomies) from 1990 to 2008. A trend of increasing hospitalizations over time was not accompanied by an increase in surgeries, producing an overall trend of decreasing surgery rates (F = 13.6, p < 0.01). Factors associated with this trend included a decrease in epilepsy hospitalizations at the highest-volume epilepsy centers, and increased hospitalizations to lower-volume hospitals that were found to be less likely to perform surgery. White patients were more likely to have surgery than racial minorities (relative risk [RR], 1.13; 95% confidence interval [CI], 1.10-1.17), and privately insured individuals were more likely to receive lobectomy than those with Medicaid or Medicare (RR, 1.28; 95% CI, 1.25-1.30).

CONCLUSION

Despite Class I evidence and subsequent practice guidelines, the utilization of lobectomy has not increased from 1990 to 2008. Surgery continues to be heavily underutilized as a treatment for epilepsy, with significant disparities by race and insurance coverage. Patients who are medically refractory after failing 2 antiepileptic medications should be referred to a comprehensive epilepsy center for surgical evaluation.

Genetic analysis and molecular mapping of a novel recessive gene xa34(t) for resistance against Xanthomonas oryzae pv. oryzae

A new bacterial blight recessive resistance gene xa34(t) was identified from the descendant of somatic hybridization between an aus rice cultivar (cv.) BG1222 and susceptible cv. IR24 against Chinese race V (isolate 5226). The isolate was used to test the resistance or susceptibility of F(1) progenies and reciprocal crosses of the parents. The results showed that F(1) progenies appeared susceptibility there were 128R (resistant):378S (susceptible) and 119R:375S plants in F(2) populations derived from two crosses of BG1222/IR24 and IR24/BG1222, respectively, which both calculates into a 1R:3S ratio. 320 pairs of stochastically selected SSR primers were used for genes' initial mapping. The screened results showed that two SSR markers, RM493 and RM446, found on rice chromosome 1 linked to xa34(t). Linkage analysis showed that these two markers were on both sides of xa34(t) with the genetic distances 4.29 and 3.05 cM, respectively. The other 50 SSR markers in this region were used for genes' fine mapping. The further results indicated that xa34(t) was mapped to a 1.42 cM genetic region between RM10927 and RM10591. In order to further narrow down the genomic region of xa34(t), 43 of insertion/deletion (Indel) markers (BGID1-43) were designed according to the sequences comparison between japonica and indica rice. Parents' polymorphic detection and linkage assay showed that the Indel marker BGID25 came closer to the target gene with a 0.4 cM genetic distance. A contig map corresponding to the locus was constructed based on the reference sequences aligned by the xa34(t) linked markers. Consequently, the locus of xa34(t) was defined to a 204 kb interval flanked by markers RM10929 and BGID25.

Relaxation and dephasing of multiexcitons in semiconductor quantum dots

We measure the dephasing time of ground-state excitonic transitions in InGaAs quantum dots under electrical injection in the temperature range from 10 to 70 K. Electrical injection into the barrier region results in a pure dephasing of the excitonic transitions. Once the injected carriers fill the electronic ground state, the biexciton to exciton transition is probed and a correlation of the exciton and biexciton phonon scattering mechanisms is found. Additional filling of the excited states creates multiexcitons that show a fast dephasing due to population relaxation.

[Analysis of complications and deaths in aged patients with obstructive jaundice]

The reasons of complications and deaths in 98 aged patients with obstructive jaundice were analysed in the paper. Among them, 52 cases were diagnosed as benign obstruction, 46 cases as malignant obstruction; 92 patients were treated by surgical management(15 died), 6 patients were treated without operation(4 died). The results showed that effective management on time and intensive perioperative care are important to minimize the mortality rate. Malignant obstructive jaundice was more harmful to the patients' renal function no the mortality rate would be increased. The operations, internal drainage and pressure reduction of biliary duct, were performed on time, thus the survival rate was improve.

Ultralong dephasing time in InGaAs quantum dots

We measure a dephasing time of several hundred picoseconds at low temperature in the ground-state transition of strongly confined InGaAs quantum dots, using a highly sensitive four-wave mixing technique. Between 7 and 100 K the polarization decay has two distinct components resulting in a non-Lorentzian line shape with a lifetime-limited zero-phonon line and a broadband from elastic exciton-acoustic phonon interactions.

Peripheral tissue distribution of orphanin FQ precusor mRNA in stroke-prone spontaneously hypertensive rats

The heptadecapeptide orphanin FQ (OFQ) is a recently discovered neuropeptide that exhibits structural features reminiscent of the opioid peptides and that is an endogenous ligant to a G protein-coupled receptor sequentially related to the opioid receptors. OFQ was originally isolated from brain, but the presence of OFQ in peripheral tissues, especially in cardiovascular system, has not been clarified. The present study was designed to investigate the peripheral tissue distribution of OFQ precusor mRNA in stroke-prone spontaneously hypertensive rats (SHRSP) and compare the difference of OFQ precusor mRNA expression in aorta or cultured vascular smooth muscle cells (VSMCs) between SHRSP and wistar-Kyoto normotensive (WKY) rats. By using quantitative reverse transcription-polymerase chain reaction (RT-PCR), OFQ precusor mRNA was detected in aorta and ovary at high levels comparable with the amounts found in brain. Moderate expression was found in testis, while a little OFQ precusor mRNA could be detected in atrium. All other peripheral tissues examined from SHRSP, including ventricle, liver, lung and kidney, showed no expression of OFQ precusor mRNA. In the vascular system, OFQ precusor mRNA was expressed in aorta, pulmonary artery, renal artery and vein at high levels comparable with the amounts found in brain. We also found that OFQ precusor mRNA levels were much higher in aorta or cultured VSMCs from SHRSP than those from WKY rats. In conclusion, the present study has shown that OFQ precusor mRNA is present in some peripheral tissues, especially in cardiovascular and reproductive system, suggesting that OFQ possibly involves in the regulation of cardiovascular and reproductive functions.

The novel behaviour of interactions between Ni2+ ion and human or bovine serum albumin

We discovered a series of novel behaviours of interactions between Ni2+ ion and human or bovine serum albumin. Our results indicated that there exist two closely neighbouring identical prior binding sites in the binding of human or bovine serum albumin with Ni2+ ions, not only one. It is very likely that, after the binding of the first Ni2+ ion, an induced slow conformational transition happens, which leads to the binding of the second Ni2+ ion and shows itself as a hysteretic effect for a process of non-enzymic protein binding with metal ions. As the concentrations of the 1:1 (molar ratio of Ni2+ ion to protein) system increase, an increasing hypochromic effect is observed. Such a hypochromic effect has not been reported previously; however, it is in accord with the mechanism of dipole-dipole interactions between the electric dipole transition moments of chromophores.