Blockage of VEGF function by bevacizumab alleviates early-stage cerebrovascular dysfunction and improves cognitive function in a mouse model of Alzheimer's disease

BACKGROUND

Alzheimer's disease (AD) is a neurodegenerative disorder and the predominant type of dementia worldwide. It is characterized by the progressive and irreversible decline of cognitive functions. In addition to the pathological beta-amyloid (Aβ) deposition, glial activation, and neuronal injury in the postmortem brains of AD patients, increasing evidence suggests that the often overlooked vascular dysfunction is an important early event in AD pathophysiology. Vascular endothelial growth factor (VEGF) plays a critical role in regulating physiological functions and pathological changes in blood vessels, but whether VEGF is involved in the early stage of vascular pathology in AD remains unclear.

METHODS

We used an antiangiogenic agent for clinical cancer treatment, the humanized monoclonal anti-VEGF antibody bevacizumab, to block VEGF binding to its receptors in the 5×FAD mouse model at an early age. After treatment, memory performance was evaluated by a novel object recognition test, and cerebral vascular permeability and perfusion were examined by an Evans blue assay and blood flow scanning imaging analysis. Immunofluorescence staining was used to measure glial activation and Aβ deposits. VEGF and its receptors were analyzed by enzyme-linked immunosorbent assay and immunoblotting. RNA sequencing was performed to elucidate bevacizumab-associated transcriptional signatures in the hippocampus of 5×FAD mice.

RESULTS

Bevacizumab treatment administered from 4 months of age dramatically improved cerebrovascular functions, reduced glial activation, and restored long-term memory in both sexes of 5×FAD mice. Notably, a sex-specific change in different VEGF receptors was identified in the cortex and hippocampus of 5×FAD mice. Soluble VEGFR1 was decreased in female mice, while full-length VEGFR2 was increased in male mice. Bevacizumab treatment reversed the altered expression of receptors to be comparable to the level in the wild-type mice. Gene Set Enrichment Analysis of transcriptomic changes revealed that bevacizumab effectively reversed the changes in the gene sets associated with blood-brain barrier integrity and vascular smooth muscle contraction in 5×FAD mice.

CONCLUSIONS

Our study demonstrated the mechanistic roles of VEGF at the early stage of amyloidopathy and the protective effects of bevacizumab on cerebrovascular function and memory performance in 5×FAD mice. These findings also suggest the therapeutic potential of bevacizumab for the early intervention of AD.

Radiation Induced Lung Injury in Rats after Pre-Oxygenation Radiotherapy

PURPOSE/OBJECTIVE(S)

Deep inspiratory breath holding (DIBH) has been widely used during the radiotherapy of thoracic tumors. The main disadvantage of voluntary DIBH is the short duration of each breath hold. The hypocapnia induced by hyperoxia (oxygen concentration > 50%) pre-oxygenation (PreO2) combined with mechanical hyperventilation has been reported to prolong the duration of single breath hold, but its safety remains controversial, especially the sensitivity of lung tissue to radiation damage under hyperoxia exposure has not been elucidated. In this study, we aim to investigate the changes of radiation induced lung injury in rats after PreO2 radiation.

MATERIALS/METHODS

We evaluated the lung tissue of rats at different time points (48h, 2w, 4w, 8w, 12w) after thoracic radiation (15Gy single fraction to the right lung), and sequenced the transcriptome of lung tissue at 48 hours after irradiation. Rat cohorts (n = 7/group): 1. Control (Con); 2. Radiation group (RT); 3. Pre-oxygenation (oxygen concentration > 90%) for 8 hours before thoracic radiation (PreO2).

RESULTS

The inflammatory exudation emerged in the pulmonary interstitium at 48 hours, and reached the most serious alveolitis after four weeks of irradiation (the comparison of alveolitis scores in RT4w vs Con4w and PreO2(4w) vs Con4w, P<0.001) on hematoxylin-eosin staining. While the alveolitis scores in RT group and PreO2 group were not statistically different at each time point. Masson staining showed that the pulmonary fibrosis in the RT group and the PreO2 group reached an obvious pathological change at 12 weeks after irradiation, but the difference between the two groups was not significant. Transcriptome sequencing showed that the number of differential genes in PreO2 vs Con was 559 (302 up-regulated genes and 257 down-regulated genes). The GO enrichment analysis indicated that chromosome segregation was the most significant functional item with P value in the comparative analysis, and the KEGG enrichment analysis suggested that cell division was the most significant enrichment pathway of these differential genes. While there was a small quantity of differential genes in PreO2 vs RT group (3 up-regulated genes and 12 down-regulated genes). Pentose and glucuronate conversions were the most significant enrichment pathway of these differential genes.

CONCLUSION

This study demonstrated that PreO2 radiotherapy did not increase the severity of radiation induced lung injury in rats compared to conventional radiotherapy. Further study should be conducted to confirm these results and to investigate the regulatory mechanism of pneumonia caused by PreO2 radiotherapy.

Digital template-guided genioplasty for patients with jaw deformity resulting from temporomandibular joint ankylosis: A comparison between single- and double-layer genioplasty

The aim of this study was to compare single- and double-layer digital template-assisted genioplasty for the correction of jaw deformity resulting from temporomandibular joint ankylosis (TMJA). Thirteen patients with jaw deformity resulting from TMJA who underwent lateral arthroplasty, costochondral graft, or total joint replacement combined with single- or double-layer digital template-assisted genioplasty were included. Computed tomography data were obtained for the preoperative design. Digital templates were designed and manufactured using three-dimensional printing to assist with the chin osteotomy and repositioning in single- or double-layer genioplasty. Of the 13 patients included, seven underwent single-layer genioplasty and six underwent double-layer genioplasty. The digital templates precisely reflected the osteotomy planes and repositioning of the chin segments intraoperatively. The radiographic evaluation showed that the patients who underwent double-layer genioplasty exhibited more chin advancement (11.95 ± 0.92 mm vs 7.50 ± 0.89 mm; P < 0.001) with a slightly larger mean surface error (1.19 ± 0.14 mm vs 0.75 ± 0.15 mm; P < 0.001) than those who underwent single-layer genioplasty. This indicates that double-layer genioplasty better promoted chin advancement and improved the facial shape, but was accompanied by more surgical error compared with the preoperative design. Furthermore, hardly any nerve damage was observed. Digital templates are useful for assisting in surgical procedures.

Dl-3-n-butylphthalide activates Nrf2, inhibits ferritinophagy, and protects MES23.5 dopaminergic neurons from ferroptosis

Ferroptosis, a newly identified iron-dependent form of cell death, has recently been implicated in the pathogenesis of Parkinson's disease (PD). Dl-3-n-butylphthalide (NBP) attenuates behavioral and cognitive deficits in animal models of PD. However, the potential of NBP to prevent dopaminergic neuron death by suppressing ferroptosis has rarely been explored. In this study, we aimed to investigate the effects of NBP on ferroptosis in erastin-induced dopaminergic neurons (MES23.5 cells) and the underlying mechanisms involved in these effects. Our results demonstrated that erastin significantly decreased viability of MES23.5 dopaminergic neurons in a dose-dependent manner, which was reversible by ferroptosis inhibitors. We further verified that NBP protected erastin-treated MES23.5 cells from death by inhibiting ferroptosis. Erastin increased the mitochondrial membrane density, caused lipid peroxidation, and decreased GPX4 expression in MES23.5 cells, which could be reversed by NBP preconditioning. NBP pretreatment suppressed erastin-induced labile iron accumulation and reactive oxygen species generation. Moreover, we demonstrated that erastin significantly reduced FTH expression, and pre-administration with NBP promoted Nrf2 translocation into the nucleus and increased the protein level of FTH. Additionally, the expression of LC3B-II in MES23.5 cells pretreated with NBP before administration of erastin was lower than that in cells treated with erastin alone. NBP reduced colocalization of FTH and autophagosomes in MES23.5 cells exposed to erastin. Finally, erastin gradually inhibited NCOA4 expression in a time-dependent manner, which was reversible by NBP pretreatment. Taken together, these results indicated that NBP suppressed ferroptosis via regulating FTH expression, which was achieved by promoting Nrf2 nuclear translocation and inhibiting NCOA4-mediated ferritinophagy. As such, NBP may be a promising therapeutic agent for the treatment of neurological diseases associated with ferroptosis.

Exploration of the α-syn/T199678/miR-519-3p/KLF9 pathway in a PD-related α-syn pathology

BACKGROUND

Kruppel-like factor 9 (KLF9) plays a key role as an inducer of cellular oxidative stress in the modulation of cell death and in oxidant-dependent tissue injury. Our previous study indicated that lncRNA-T199678 (T199678) affected the expression of KLF9 in an α-synuclein (α-syn) induced cellular model. However, the roles of interactions among α-syn, T199678, KLF9 and related microRNAs (miRNAs) in the Parkinson's disease (PD)-related α-syn pathology are unclear and were therefore investigated in this study.

METHODS

An α-syn-injected mouse model and an α-syn exposed SY-SH5Y cellular model were used in this study. We confirmed the utility of these established models with morphological and behavioral methods. We checked how expression of T199678 and KLF9 were affected by α-syn and demonstrated their interaction by fluorescence in situ hybridization (FISH) staining and western blots. We analyzed expression in ROS+ cells by immunohistochemistry. Finally, we obtained seven miRNAs through bioinformatic analysis simultaneously affected by T199678 and α-syn and verified these with RT-PCR.

RESULTS

We found that expression of KLF9 was regulated by T199678, whereas expression of T199678 was not affected by KLF9 in the α-syn exposed SY-SH5Y cells. These findings suggest that KLF9 is the downstream gene regulated by T199678, whereas miR-519-3p may play a contributing role. We also confirmed that α-syn injection upregulated the expression of ROS, which could be downregulated by upregulation of T199678, indicating an anti-oxidative role of T199678 in the α-syn-related mechanisms.

CONCLUSIONS

Our results indicate the existence of a potential α-syn/T199678/miR-519-3p /KLF9 pathway in PD-related α-syn pathology. This pathway might explain oxidative stress processes in α-syn-related mechanisms, which requires further verification.

[Clinical characteristics and pregnancy outcomes of pregnant women with left ventricular non-compaction]

Objective: To investigate the clinical characteristics and pregnancy outcomes in pregnant women with left ventricular non-compaction (LVNC). Methods: The clinical data of seven pregnant women with LVNC from January 2011 to December 2021 in Beijing Anzhen Hospital,Capital Medical University were retrospectively analyzed, including age, gestational age of symptom first occured, LVNC history, clinical symptoms, New York Heart Association (NYHA) cardiac function class, echocardiography, blood brain natriuretic peptide (BNP), treatment and the maternal and fetal outcomes. Results: Five cases were diagnosed before pregnancy, of which there were three women with medication; one case diagnosed in the month of pregnancy; one case diagnosed at 36 weeks of gestation. NYHA cardiac function was grade Ⅰ in four cases and grade Ⅱ in three cases before or during the first trimester of pregnancy. Of the five pregnant women who underwent echocardiography, there were one case of left ventricular insufficiency, three cases of mild left ventricular dysfunction and one case of normal left ventricular function before or during the first trimester of pregnancy. Of the five pregnant women to the second and third trimester of pregnancy, there were one case of grade Ⅳ, one case of grade Ⅲ, two cases of grade Ⅱ-Ⅲ and one case of grade Ⅱ in NYHA class ; three cases of left ventricular insufficiency, two cases of normal left ventricular function by echocardiography four cases had cardiac symptoms at 15-24 weeks of gestation and were treated with medication. In four cases, blood BNP increased to 214-1 197 ng/L during pregnancy, and were 89-106 ng/L after termination of pregnancy. There were 4 cases with arrhythmia. Indications for termination of pregnancy: LVNC complicated with heart failure in two cases, LVNC complicated with decreased cardiac function and threatened preterm birth in one case, complicated with pregnancy at full term in two cases, LVNC complicated with severe pulmonary hypertension in one case, and left ventricular dysfunction in one case. Cesarean section in four cases in the third-trimester, in one case in the second-trimester, and forceps curettage in two cases were taken. Two full-term infants,two preterm infants were born without LVNC. Conclusions: Women diagnosed with LVNC and low left ventricular ejection fraction before pregnancy are more prone to decreased cardiac function during pregnancy. Carrying out pregnancy risk assessment and strengthening the multi-disciplinary team management of high risk factors in pregnancy are conducive to achieve good pregnancy outcomes.

NLR1 is a strong candidate for the Rm3 dominant green peach aphid (Myzus persicae) resistance trait in peach

The green peach aphid (GPA), Myzus persicae, is a polyphagous, sap-sucking aphid and a vector of many plant viruses. In peach, Prunus persica, three individual dominant GPA resistance loci have been genetically defined (Rm1-3), but knowledge of the underlying genes is limited. In this study, we focused on the Rm3 locus. Bulk segregant analysis (BSA) mapping in segregating progeny populations delimited Rm3 to an interval spanning 160 kb containing 21 genes on chromosome 1. RNA-seq data provided no evidence of candidate genes, but chromosomal structural variations were predicted around a nucleotide-binding site-leucine-rich repeat (NLR) gene (ppa000596m) within the Rm3 fine-mapping interval. Following bacterial artificial chromosome (BAC) library construction for a GPA-resistant peach cultivar and the sequencing of three target BAC clones, a chromosomal structural variation encompassing two novel TIR-NLR-class disease resistance (R) protein-coding genes was identified, and the expressed NLR gene (NLR1) was identified as a candidate for M. persicae resistance. Consistent with its proposed role in controlling GPA resistance, NLR1 was only expressed in the leaves of resistant peach phenotypes. A molecular marker that was designed based on the NLR1 sequence co-segregated with the GPA-resistant phenotype in four segregating populations, 162 peach cultivars, and 14 wild relatives, demonstrating the dominant inheritance of the Rm3 locus. Our findings can be exploited to facilitate future breeding for GPA-resistance in peach.

Pressure sensing with high-finesse monolithic buckled-dome microcavities

We describe the use of on-chip buckled-dome Fabry-Perot microcavities as pressure sensing elements. These cavities, fabricated by a controlled thin-film buckling process, are inherently sealed and support stable optical modes (finesse >10³), which are well-suited to coupling by single-mode fibers. Changes in external pressure deflect the buckled upper mirror, leading to changes in resonance wavelengths. Experimental shifts are shown to be in good agreement with theoretical predictions. Sensitivities as large as ∼1nm/kPa, attributable to the low thickness (<2µm) of the buckled mirror, and resolution ∼10Pa are demonstrated. We discuss potential advantages over traditional low-finesse, quasi-planar Fabry-Perot pressure sensors.

Monolithically integrated membrane-in-the-middle cavity optomechanical systems

We describe curved-mirror Fabry-Perot cavities with embedded silicon nitride membranes, fabricated using a monolithic surface-micromachining process. The presence of the suspended membranes was confirmed by confocal microscopy, and their properties were verified through optical studies and thermomechanical calibration of mechanical/vibrational noise spectra measured at room temperature and atmospheric pressure. The cavities exhibit reflectance-limited finesse (F ∼ 10³) and wavelength-scale mode volumes (VM ∼ 10·λ³). The short cavity length (L ∼ 2·λ) results in large optomechanical coupling, which is desirable for numerous applications in sensing and quantum information.

Widely tunable bandpass filter based on resonant optical tunneling

We describe a tunable bandpass filter and polarizer based on resonant tunneling through an air gap between two hemi-cylindrical prisms coated with 4-layer a-Si/SiO₂ matching stacks. Tuning is achieved by simultaneous variations in the incident angle and the air gap thickness, enabling the pass-band center wavelength to be continuously adjusted over a very wide range (potentially ~1000 - 1800 nm) with an approximately fixed fractional bandwidth (Δλ/λ ~1%). An analytical derivation of the conditions required to produce a flat-top TE pass-band at a desired wavelength is given. The filter provides excellent out-of-band rejection and strong suppression of the orthogonal TM polarization over the entire tuning range. For applications involving collimated light, it could be a useful alternative to existing widely tunable filters based on gratings or liquid crystals.

Expression signatures of long non-coding RNA in the substantia nigra of pre-symptomatic mouse model of Parkinson's disease

Parkinson's disease (PD) is an age-dependent neurodegenerative disease that can be caused by a variety of factors. Growing evidence shows that prior to the motor phase of PD can express molecular or imaging markers. Many long non-coding RNAs (lncRNAs) have been identified in neurodegenerative disease. However, the biogenesis and function of lncRNAs in the pre-symptomatic stage of PD is poorly understood. Here, we profiled the expression of lncRNAs and mRNAs in the substantia nigra pars compacta (SNpc) of pre-symptomatic mice over-expressing human A30P*A53T α-synuclein by microarray analysis. Based on the Pearson correlation analysis, lncRNA/mRNA co-expression network was constructed. GO enrichment and pathway analysis of lncRNAs-coexpressed mRNAs was conducted to identify the related biological function and pathologic pathways. Real-time PCR was used to detect the expression pattern of lncRNAs. Approximately 756 lncRNAs were aberrantly expressed in the SNpc of early over-expressing human A30P*A53T α-synuclein transgenic mice, including 477 downregulated lncRNAs and 279 upregulated lncRNAs. GO analysis indicated that these lncRNAs-coexpressed mRNAs were targeted to regulation of transcription (ontology: biological process), membrane (ontology: cellular component), and protein binding (ontology: molecular function). Pathway analysis indicated that lncRNAs-coexpressed mRNAs were mostly enriched in axon guidance signaling pathway. In conclusion, the present study firstly identified a series of novel early PD-associated lncRNAs caused by mutant α-synuclein. Further study the function of these aberrantly expressed lncRNAs may provide insight into treatment of early PD.

GSTP1 Ile105Val and XRCC1 Arg399Gln gene polymorphisms contribute to the clinical outcome of patients with advanced non-small cell lung cancer

Glutathione S-transferase P1 (GSTP1) and X-ray repair cross-complementing group 1 (XRCC1) genetic variations may in-fluence the efficacy of chemotherapy in various cancers. We investi-gated the possible roles of GSTP1 Ile105Val and XRCC1 Arg194Trp, and Arg399Gln gene polymorphisms in the prognosis of advanced non-small cell lung carcinoma (NSCLC) patients with cisplatin-based chemotherapy. Between January 2010 and December 2012, this study consecutively recruited 141 patients with advanced NSCLC from the First People's Hospital of Yunnan Province. Logistic regression analy-sis showed that individuals carrying the GG genotype were associated with a better response to chemotherapy than those with the wide-type genotype, with an adjusted odds ratio (95% confidence interval, CI) of 4.07 (1.06-25.06). Moreover, we observed that the AA genotype of XRCC1 Arg399Gln was correlated with a greater complete response + partial response to chemotherapy than that with the GG genotype (odds ratio = 2.71, 95%CI = 1.13-10.08). Based on the Cox hazard proportional model, the GG genotype of GSTP1 Ile105Val was found to be associated with a lower risk of death from all causes as compared to that with the AA genotype (hazard ratio = 0.07, 95%CI = 0.01-0.34). In summary, we suggest that GSTP1 Ile105Val and XRCC1 Arg399Gln polymorphisms could influence the response to chemotherapy and sur-vival of advanced NSCLC.

Serum Irisin Level is Higher and Related with Insulin in Acanthosis Nigricans-related Obesity

OBJECTIVE

Acanthosis nigricans (AN) is proved to be a skin phenotype of hyperinsulinemia especially in obese patients. Irisin is a new myokine which plays an important role in metabolic disorders, such as obesity, insulin resistance, and type 2 diabetes. The role of irisin in the development of AN-related obesity is not yet understood. In this study, we aimed to investigate the relationship between irisin and AN-related obesity. Patients & Measurements: 30 obese patients without AN (OB group), 30 obese patients with AN (AN group), and 20 age-matched healthy volunteers (control group, CON) were included in this study. Weight, BMI, lipid profile, FFA, UA, and CRP were measured in all participants. Oral Glucose Tolerance tests (OGTT) were performed and serum glucose and plasma insulin were measured at 0, 30, 60,120 and 180 min. The AUC (area under curve) of glucose and insulin was calculated. Serum irisin was measured by ELISA.

RESULTS

Hyperinsulinemia is found in both AN and OB groups. The AN group had higher levels of insulin but better blood glucose tolerance and insulin response. The difference in irisin levels between the 3 groups was statistically significant, with the AN group showing the highest serum level of irisin. Serum irisin levels were positively correlated with BMI, and fasting insulin.

CONCLUSION

AN is a state of hyperinsulinmia and has better insulin response and glucose tolerance compared to obese patients without AN. Serum irisin may be a protective factor against impaired beta cell function in obesity with AN.

Scd1ab-Xyk: a new asebia allele characterized by a CCC trinucleotide insertion in exon 5 of the stearoyl-CoA desaturase 1 gene in mouse

We describe here a spontaneous, autosomal recessive mutant mouse suffering from skin and hair defects, which arose in the outbred Kunming strain. By haplotype analysis and direct sequencing of PCR products, we show that this mutation is a new allele of the asebia locus with a naturally occurring mutation in the Scd1 gene (a CCC insertion at nucleotide position 835 in exon 5), which codes for stearoyl-CoA desaturase 1. This mutation introduces an extra proline residue at position 279 in the Scd1 protein. The mutant mice, originally designated km/km but now assigned the name Scd1ab-Xyk (hereafter abbreviated as abXyk/abXyk), have a similar gross and histological phenotype to that reported for previously characterized allelic asebia mutations (Scd1ab, Scd1abJ, Scd1ab2J, and Scd1tm1Ntam). Histological analysis showed they were also characterized by hypoplasic sebaceous glands and abnormal hair follicles. In a cross between Kunming- abXyk/abXyk and ABJ/Le-abJ/abJ mice, all the progeny showed the same phenotype, indicating that the two mutations were non-complementing and therefore allelic. Comparisons with the other four allelic mutants indicate that the Scd1ab-Xyk mutation causes the mildest change in Scd1 function. This new mouse mutant is a good model not only for the study of scarring alopecias in humans, which are characterized by hypoplasic sebaceous glands, but also for studying the structure and function of the Scd1 protein.

Germline mutational analysis of CDH1 and pathologic features in familial cancer syndrome with diffuse gastric cancer/breast cancer proband in a Chinese family

AIMS

Hereditary non-polyposis colorectal cancer, thyroid medullary carcinoma, breast/ovarian cancer and gastric cancer/breast cancer syndrome are encountered in surgery. Some gastric cancer/breast cancer syndrome may be the result of a CDH1 germline mutation. This is the first report of CDH1 germline mutations gastric cancer/breast cancer syndrome in Chinese patients.

METHODS

Peripheral blood from the proband, as well as, her first and second degree relatives was collected and CDH1 gene exon 1-16 mutations were screened. E-cadherin/beta-catenin proteins expression and histopathologic features were examined on gastric cancer/breast cancer tissues from the proband.

RESULTS

A C-->T nucleotide substitution at exon 13 (mRNA 2200 locus, Accession number NM-004360) was found. This was a transition from GCC-->GCT in DNA sequence (Ala154Ala). Diffuse-type gastric cancer and infiltrating ductal breast carcinoma were present. Both tumours preserved E-cadherin/beta-catenin expression immunohistochemically.

CONCLUSIONS

Familial cancer syndrome with diffuse-type gastric cancer/breast cancer proband in Chinese has a propensity of early onset during lifespan. No truncating or splice-site CDH1 mutations had been identified in this family. A silent nucleotide variation in exon 13 of the CDH1 gene may contribute to some forms of cancer susceptibility.

Identification of a locus for porokeratosis palmaris et plantaris disseminata to a 6.9-cM region at chromosome 12q24.1-24.2

BACKGROUND

Porokeratosis palmaris et plantaris disseminata (PPPD) is a rare autosomal dominant dyskeratotic disorder characterized by a cornoid lamella with parakeratosis, hyperkeratosis and loss of granular layers. The genetic basis of this disease is still unknown. Two loci for disseminated superficial actinic porokeratosis (DSAP) were found to be located on 12q23.2-24.1 and 15q25.1-26.1. Both PPPD and DSAP are disseminated types of porokeratosis.

OBJECTIVES

To locate the locus for PPPD, thereby facilitating the identification of this disease gene and leading to an understanding of the pathogenesis of porokeratosis.

METHODS

Genotyping was performed in a Chinese family with PPPD using polymorphic microsatellite markers on 12q and 15q.

RESULTS

The locus for PPPD is located within a 6.9-cM region between markers D12S1613 and D12S1341, with a maximum two-point LOD score of 8.14 (theta = 0.00) at D12S1335.

CONCLUSIONS

This study provides a map location for isolation of a gene causing PPPD.

[Cloning and biological regulating effects of human WAF1 gene]

OBJECTIVE

To clone human WAF1 gene and construct WAF1-pcDNA3 recombinant plasmid, and to explore the biological regulating effects of WAF1 gene.

METHODS

Human WAF1 gene was amplified and cloned into pcDNA3 vector by RT-PCR and DNA direct sequencing from Hela cells. By immunofluorescence and immunohistochemistry staining, the identify the expression of the inserted WAF1 gene and its biological regulating effects on Rb, cyclin D1 gene.

RESULTS

Human WAF1-pcDNA3 recombinant plasmid was correctly constructed and transfected into Hct-8 cells. P21WAFI/Clip was successfully expressed. The functional characterization of the inserting WAF1 gene implied that P21WAF1/Cip1 expression could upregulate Rb gene and downregulate cyclin D1 gene at protein level.

CONCLUSION

Human WAF1-pcDNA3 can modulate the protein expression of the downstream gene.

A new locus for hereditary gingival fibromatosis (GINGF2) maps to 5q13-q22

Gingival fibromatosis (GINGF) is an oral disorder characterized by enlargement of the gingiva. It occurs either as the sole phenotype or combined with other symptoms. Thus far, one GINGF locus has been mapped on chromosome 2, at 2p21, and a second possible locus has been mapped to 2p13. However, the genes responsible for this disorder have not been elucidated. We identified a four-generation Chinese GINGF family in which the disease manifests within 1 year after birth. After exclusion of the two known GINGF loci in this family, we performed a genome-wide search to map the chromosome location of the responsible gene. We identified a new locus, GINGF2, on chromosome 5q13-q22 with a maximum two-point lod score of 4.31 at D5S1721 (theta = 0.00). Haplotype analysis placed the critical region in the interval defined by D5S1491 and D5S1453. Within this region, calcium/calmodulin-dependent protein kinase IV (CAMK4) is a strong candidate.

Improved orthopaedic bone cement formulations based on rubber toughening

Poly(methylmethacrylate) (PMMA) bone cements have been used for the fixation of hip and knee implants since the early 1960s. Aseptic loosening, related to fracture of the PMMA, continues to be the primary mode of failure for these prostheses. Failed prostheses must be replaced causing additional expense and patient trauma. Furthermore, the average lifetime of the revised prosthesis is significantly lower than that of a primary prosthesis. Recent work by Moseley and co-workers led to the development of a promising new rubber toughened cement. It is comprised of a matrix of the traditional PMMA with dispersed rubber particles to modify mechanical properties and, in particular, improve fracture toughness. The fracture toughness of the experimental material was 167% greater than the toughness of a nontoughened control; however, the elastic modulus and compressive strength were reduced. The reductions in properties should not pose a clinical problem based on results of the implant model reported by Moseley. More serious concerns were mixing and delivery problems and high residual monomer concentrations. The formulation and chemical/mechanical characterization of new toughened acrylic formulations that have residual monomer levels equivalent to Simplex and better mixing properties are reported.

Dentinogenesis imperfecta 1 with or without progressive hearing loss is associated with distinct mutations in DSPP

Dentinogenesis imperfecta 1 (DGI1, MIM 125490) is an autosomal dominant dental disease characterized by abnormal dentin production and mineralization. The DGI1 locus was recently refined to a 2-Mb interval on 4q21 (ref. 1). Here we study three Chinese families carrying DGI1. We find that the affected individuals of two families also presented with progressive sensorineural high-frequency hearing loss (gene DFNA39). We identified three disease-specific mutations within the dentin sialophosphoprotein gene (DSPP) in these three families. We detected a G-->A transition at the donor-splicing site of intron 3 in one family without DFNA39, a mutation predicted to result in the skipping of exon 3. In two other families affected with both DGI1 and DFNA39, however, we identified two independent nucleotide transversions in exons 2 and 3 of DSPP, respectively, that cause missense mutations of two adjacent amino-acid residues in the predicted transmembrane region of the protein. Moreover, transcripts of DSPP previously reported to be expressed specifically in teeth are also detected in the inner ear of mice. We have thus demonstrated for the first time that distinct mutations in DSPP are responsible for the clinical manifestations of DGI1 with or without DFNA39.

Refinement of the locus for autosomal dominant hereditary gingival fibromatosis (GINGF) to a 3.8-cM region on 2p21

Hereditary gingival fibromatosis (HGF, MIM 135300; approved gene symbol GINGF) is an oral disease characterized by enlargement of gingiva. Recently, a locus for autosomal dominant HGF has been mapped to an 11-cM region on chromosome 2p21. In the current investigation, we genotyped four Chinese HGF families using polymorphic microsatellite markers on 2p21. The HOMOG test provided evidence for genetic homogeneity, with evidence for linkage in four families (heterogeneity versus homogeneity test HOMOG, chi(2) = 0. 00). A cumulative maximum two-point lod score of 5.04 was produced with marker D2S390 at a recombination frequency of &theta; = 0 in the four linked families. Haplotype analysis localized the hereditary gingival fibromatosis locus within the region defined by D2S352 and D2S2163. This region overlaps by 3.8 cM with the previously reported HGF region. Single-strand conformation polymorphism and sequence analysis of the coding region of cytochrome P450 1B1 (CYP1B1) excluded it as a likely candidate gene.

[The diagnostic value of computed tomography and ultrasonography for detecting hypoxic-ischemic encephalopathy]

OBJECTIVE

To investigate diagnostic value of computed tomography (CT) and ultrasonography for detecting hypoxic-ischemic encephalopathy (HIE) and to evaluate their clinical implications.

METHODS

94 neonates were examined with CT and ultrasonography, respectively, for detecting HIE and the results were compared to clinical investigation.

RESULTS

Significant difference (P < 0.01) was found for diagnosis of mild and moderate HIE by CT and ultrasonography. Compared with clinical diagnosis, the agreement rates of ultrasonography and CT were 83% and 39% (P < 0.01) for mild HIE, and 100% and 43% (P < 0.01) for moderate HIE respectively. There was no difference for detecting severe HIE among clinical diagnosis, CT and ultrasonography. Additionally, 9 cases with intracranial hemorrhage were detected by CT in which only 3 cases were found by ultrasonography.

CONCLUSIONS

Compared with clinical finding for diagnosis of mild and moderate HIE, the agreement rate of ultrasonography is higher than that of CT. However, CT is more sensitive to detect intracranial hemorrhage than ultrasonography.

Bromine-, chlorine-, and mixed halogen-substituted 4-methyl-2(5H)-furanones: synthesis and mutagenic effects of halogen and hydroxyl group replacements

The versatility of 4-(hydroxymethyl)-2(5H)-furanone as a starting point for the synthesis of several bromine and mixed halogen analogues of the potent water mutagen 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) has been demonstrated. However, in some preparations the yields of desired products were lower for bromine- than chlorine-substituted counterparts. A total of 12 bromine-, chlorine-, and mixed halogen-substituted 4-methyl-2(5H)-furanones were tested repeatedly in 10 independent experiments for levels of Salmonella typhimurium (TA100) mutagenicities. The purpose of these experiments was to determine the mutagenic response to changing halogen content, type, and position as well as to learn the measure of these responses in the presence and absence of the C-5 OH group. Mutagenicities reached levels of 10(3) and 10(2) rev/nmol for all trihalo- and dihalo-4-methyl-5-hydroxy-2(5H)-furanones, respectively, notwithstanding substitutions by bromine or chlorine. Trihalides lacking the C-5 hydroxyl group possessed mutagenicities of the order of 10(2) rev/nmol, while hydroxyl group absence in the dihalides resulted in potency levels of slightly less than 10 rev/ nmol. Pairwise comparisons of compound mutagenicities showed that overall the C-5 H-by-OH replacement and, next in importance, increasing the number of C-6 halogens from one to two resulted in the greatest enhancements of mutagenicities. However, in comparing compound pairs within two different sets of four di- and trihalides, it was observed that replacement of a C-5 H by OH enhanced mutagenicity more for the dihalides than the trihalides indicating that increasing the C-6 halogen number simultaneously with replacing C-5 H by OH results in a nonlinear, additive enhancement. For fewer than half of the compound pairs compared, changing the C-6 halogen from chlorine to bromine resulted in small increases in mutagenicity, and for the remaining compound pairs, no increase could be discerned. This result points to the relative unimportance of only C-6 halogen type as a determinant of mutagenicity. Similarly, no impact on mutagenicity was observed for changing only the halogen type attached to C-3.

Test of chiral recognition in the Salmonella typhimurium (TA100) mutagenicity of mucochloric acid-cysteine adducts

A difference in biological response to enantiomers is not an uncommon observation and is, therefore, to be expected in various manifestations of genotoxicity. The bacterial mutagen mucochloric acid (2,3-dichloro-5-hydroxy-2(5H)-furanone) has one chiral center, at C-5, but this mutagen exists in racemic form because of the facile stereoisomerization occurring by the mechanism of ring-chain tautomerism. Two readily synthesized enantiomeric analogs of mucochloric acid, as well as the racemic form of the two, were prepared from mucochloric acid and (R)-(+)-, (S)-(-)-, and (R,S)-(+/-)-cysteine. Using Salmonella typhimurium (TA100), the enantiomeric compounds were assayed together in four dose/response assays along with mucochloric acid, the reference mutagen. In three of the same four assays, the racemic form was also assayed. Neither statistically significant differences in mutagenicity, as determined in slope responses, nor distinctions from the plotted curves were observed among the two enantiomers and their racemic form. Therefore, no enantiospecific interaction between enantiomers and chiral DNA or enzymes involved in repair or replication could be concluded.

Structure-activity relationships of bacterial mutagens related to 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone: an emphasis on the effect of stepwise removal of chlorine from the dichloromethyl group

The Salmonella typhimurium (TA100) mutagenicities of six structural analogues of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) were determined and compared. These were also compared to previously determined mutagenicities for another four analogues. This study was conducted for the primary purpose of ascertaining the effect of C-6 chlorine-by-hydrogen replacement on mutagenicity. The compounds assayed were 3-chloro-4-(chloromethyl)-5-hydroxy-2(5H)-furanone (3), 3-chloro-4-(chloromethyl)-2(5H)-furanone (4), 3-chloro-4-methyl-5-hydroxy-2(5H)-furanone (7), 3-chloro-4-methyl-2(5H)-furanone (8), 4-methyl-5-hydroxy-2(5H)-furanone (9), and 4-methyl-2(5H)-furanone (10). Compounds 3, 4, and 7 were mutagenic whereas 8-10 were not. All six compounds were stable under assay conditions. Mutagenicity data for the three active compounds were combined with data of another four active compounds studied previously to obtain an expanded data set. Mutagenicities of the seven compounds were compared, pairwise, in 21 comparisons and then by multiple regression analysis. On the average, chlorine-by-hydrogen replacement of a single chlorine located at a chloromethyl group (C-6) had a markedly greater effect in reducing mutagenicity than a similar replacement at C-3 or a hydroxyl-by-hydrogen replacement at C-5. The chlorine-by-hydrogen replacement at C-6 of compound 3 resulted in the greatest mutagenicity reduction of any single replacement and amounted to a 10(3)-fold diminished mutagenicity.