FNDC4 reduces inflammation, proliferation, invasion and migration of rheumatoid synovial cells by inhibiting CCL2/ERK signaling

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic joint inflammation. Fibronectin type III domain-containing protein 4 (FNDC4) is a secretory factor that can regulate inflammatory diseases. However, the role of FNDC4 in RA has not been reported so far.

METHODS

The expression of FNDC4 in synovial tissues of RA was analyzed by GEO database (GSE55235 dataset). Then, the expression of FNDC4 in RA fibroblast-like synoviocytes (RA-FLSs) was detected by RT-qPCR and western blot. After constructing FNDC4 overexpression plasmid, cell proliferation and apoptosis were detected. Wound healing and transwell assays were used to detect cell migration and invasion. Then we examined the expression of cytokines related to cell inflammation. Subsequently, the regulatory mechanism of FNDC4 was further discussed. We detected the expression of CCL2 and ERK signaling pathway related proteins downstream of FNDC4. Finally, the mechanism was discussed through the overexpression of FNDC4 and CCL2 and the addition of ERK pathway activator tBHQ.

RESULTS

GEO database showed that FNDC4 expression decreased in synovial tissues of RA. FNDC4 expression was also decreased in RA-FLSs. Overexpression of FNDC4 inhibited the proliferation, invasion and migration of RA-FLSs whereas promoted the cellapoptosis. Overexpression of FNDC4 inhibited the release of inflammatory factors in RA-FLSs. The regulatory effect of FNDC4 is achieved by inhibiting the CCL2/ERK signaling pathway.

CONCLUSION

FNDC4 reduces inflammation, proliferation, invasion and migration of RA-FLSs in RA by inhibiting CCL2/ERK signaling.

[A close contact of coronavirus disease 2019 with severe imported malaria: a case report]

This article presents a severe cerebral malaria patient in shock with a close contact of COVID-19 that was successfully cured in a negative pressure ward during the global pandemic of COVID-19. The patient experienced a sudden onset of high fever and coma in a designated isolation hotel after returning from Africa, and was transferred to a designated hospital. Following antimalarial therapy, blood pressure elevation, increase of blood volume, bedside hemodialysis, mechanical ventilation, plasma and platelet transfusions, the case gradual recovered.

Knowledge, attitude, and practice of nephrologists on the decision for renal replacement therapy

BACKGROUND

This study aimed to investigate the Knowledge, Attitude, and Practice (KAP) of nephrologists on the decision of renal replacement therapy (RRT), including peritoneal dialysis, hemodialysis, and kidney transplantation.

METHODS

This multicenter cross-sectional study was conducted on qualified nephrologists who volunteered to participate between July and August 2022 by using a self-administered questionnaire.

RESULTS

Among 327 nephrologists, the total knowledge, attitude, and practice scores were 12.03 ± 2.11/16, 58.39 ± 6.62/75, and 27.15 ± 2.74/30, respectively. Multivariate logistic regression analysis showed that the attitude score (peritoneal dialysis: OR = 1.19, 95%CI: 1.13-1.25, P < 0.001; hemodialysis: OR = 1.14, 95%CI: 1.09-1.19, P < 0.001; kidney transplantation: OR = 1.12, 95%CI: 1.07-1.16, P < 0.001), 41-50 years of age (peritoneal dialysis: OR = 0.45, 95%CI: 0.21-0,98, P = 0.045; hemodialysis: OR = 0.27, 95%CI: 0.12-0.60, P = 0.001; kidney transplantation: OR = 0.45, 95%CI:0.20-0.97, P = 0.042), and > 50 years of age (peritoneal dialysis: OR = 0.27, 95%CI: 0.08-0.84, P = 0.024; hemodialysis: OR = 0.45, 95%CI: 0.20-0.97, P = 0.042; kidney transplantation: OR = 0.24, 95%CI: 0.08-0.77, P = 0.016) were independently associated with the consideration score of peritoneal dialysis, hemodialysis, and kidney transplantation.

CONCLUSION

Better attitudes may lead to more consideration by nephrologists when choosing between peritoneal dialysis, hemodialysis, and kidney transplantation and relatively less consideration by senior physicians when making decisions; in addition, having good knowledge and good attitudes may lead to better practice.

Bioinformatics analysis of epigenetic and SNP-related molecular markers in systemic lupus erythematosus

We analyzed gene expression in peripheral blood mononuclear cells (PBMCs) from patients with systemic lupus erythematosus (SLE) using public databases. The goal was to identify lupus biomarkers by determining whether differentially expressed genes are mediated by methylation, miRNA, or SNP. Two cDNA microarrays were subjected to integration analysis, and we calculated the mutually differentially expressed genes (|log2fold change (FC)| > 1, P < 0.05). These genes were analyzed using gene otology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, and protein-protein interaction (PPI) networks. The differences in methylation sites for two methylation chips were calculated and the differentially methylated sites were annotated. These genes were compared to the differentially expressed genes. We obtained 135 differentially expressed microRNAs from the microRNA-chip results using PBMCs from SLE and healthy individuals. Predictive microRNA target genes were identified using GO, KEGG pathways, and PPI networks. The target genes identified were compared to the differentially expressed genes. We downloaded Chinese SLE genome-wide association study data from SLE-related literature, analyzed the loci with a P value < 0.05, and used annotated SLE-associated SNPs. We selected the genes corresponding to an SNP located on an exon and determined the intersection with the differentially expressed genes. We found 18 differentially expressed genes in both cDNA microarrays. The methylation chips had 50 corresponding methylation sites. On the basis of these results, we identified two genes, IFI44 and IFI44L. We further identified 135 differentially expressed microRNAs predicted to affect 5766 target genes. Two identified genes were in common with the differentially expressed genes. Finally, SNP annotated genes and cDNA chip genes overlap with identified MX1. Therefore, we used existing data to analyze the causes of differential gene expression in SLE, introducing new methods for determining biomarkers and therapeutic targets.

Curcumin inhibits hypoxia inducible factor-1α-induced inflammation and apoptosis in macrophages through an ERK dependent pathway

OBJECTIVE

Atherosclerosis, a kind of peripheral arterial disease with chronic inflammation, leads to the dysfunction of the vascular system and many other diseases. Hypoxia has been proven to participate in the progression of atherosclerosis, while curcumin can inhibit hypoxia-inducible factor 1α (HIF-1α). However, the underlying mechanisms are still elusive.

PATIENTS AND METHODS

qRT-PCR was used to examine the expression of HIF-1α, IL-6 and TNFα of macrophages under hypoxic condition. Western blot was applied to examine the changes of HIF-1α, ERK and p-ERK after treatment with curcumin. Oli Red O staining and enzymatic assay were used to examine the lipid and total cholesterol in macrophages, respectively. ELISA was used to examine the release of IL-6 and TNFα by macrophages. FACS and MTT assays were applied to examine the apoptosis and proliferation of macrophages.

RESULTS

Here, we found curcumin inhibited the expression of HIF-1α at the protein level in macrophages under hypoxic condition and curcumin and HIF-1α inhibitors repressed the total cholesterol and lipid level in macrophage under hypoxic condition. Moreover, curcumin also decreased the expression of HIF-1α downstream genes, VEGF, HMOX1, ROS and PDGF. Then, the data show the HIF-1α-induced apoptosis and inflammation of macrophages were inhibited by curcumin. Curcumin also rescued the proliferation defect of macrophages caused by hypoxia. Furthermore, we found it inhibited the expression of HIF-1α via ERK signaling pathway.

CONCLUSIONS

We describe that curcumin inhibited the HIF-1α-induced apoptosis and inflammation of macrophages via ERK signaling pathways. These results suggest curcumin can be used for the treatment of atherosclerosis.

Characterizing the gut microbiota in patients with chronic kidney disease

Objectives: Emerging evidence suggests that gut microbiota dysbiosis plays a critical role in chronic kidney disease (CKD). However, the relationship between altered gut microbiome profiles and disease severity remains unclear. In this study, we sought to characterize the gut microbiota in CKD patients compared to healthy controls, and to explore potential relationships between gut microbiota composition and disease severity. Methods: Fecal samples were collected from 95 patients at different stages of CKD (non-dialysis patients from stage 1 to 5) and 20 healthy controls. Bacterial DNA was extracted for 16S ribosomal DNA sequencing targeting the V3-V4 region. The diversity and relative abundance of gut microbiota were analyzed as outcome indicators. Results: Differences were observed in the microbial composition and diversity of fecal samples from CKD patients and healthy controls. Specifically, disease severity was found to alter gut microbiota composition. Compared to that in healthy controls, CKD patients showed an increased abundance of Proteobacteria and decreased Synergistetes, most notably in disease stage 5. Lower levels of butyrate-producing bacteria and higher levels of potential pathogens were also detected in CKD patients. Further, Pyramidobacter and Prevotellaceae_UCG-001 were significantly decreased in the CKD1 group compared with healthy controls. Notably, nine microbial genera, including Escherichia-Shigella, Parabacteroides, Roseburia, rectale_group, Ruminococcaceae_NK4A214_group, Prevotellaceae_UCG.001, Hungatella, Intestinimonas, and Pyramidobacter, identified using a random forest model, distinguished between patients with CKD and healthy controls with high accuracy. Functional analysis also revealed that fatty acid and inositol phosphate metabolism were enriched in the CKD group, while aminoacyl-tRNA biosynthesis, oxidative phosphorylation, phenylalanine, tyrosine, and tryptophan biosynthesis, thiamine metabolism, pantothenate, and CoA biosynthesis, as well as valine, leucine, and isoleucine biosynthesis were enriched in healthy controls. Conclusion: Gut microbiota composition and function are associated with CKD severity. And, specific gut microbes are potentially helpful for CKD early diagnosis and prognosis monitoring.

Fecal microbiota characteristics of Chinese patients with primary IgA nephropathy: a cross-sectional study

BACKGROUND

Growing evidence has shown that the gut-renal connection and gut microbiota dysbiosis play a critical role in immunoglobulin A nephropathy (IgAN). However, the fecal microbiome profile in Chinese patients with IgAN remains unknown. A cross-sectional study was designed for the first time to investigate the fecal microbiota compositions in patients with primary IgAN in China and to evaluate the relationship between the fecal microbiome and IgAN clinical presentation.

METHODS

Fecal samples were collected from 17 IgAN patients and 18 age-, sex-, and body mass index-matched healthy controls, and bacterial DNA was extracted for 16S ribosomal RNA gene sequencing targeting the V3-V4 region.

RESULTS

Fecal samples from the IgAN patients and healthy controls showed differences in gut microbiota community richness and compositions. Compared to the healthy controls, IgAN patients at the phylum level had an increased abundance of Fusobacteria, but a decreased abundance of Synergistetes. The significantly increased genera in the IgAN group were Escherichia-Shigella, Hungatella, and Eggerthella, all of which possess pathogenic potential. Furthermore, the genus Escherichia-Shigella was negatively associated with the estimated glomerular filtration rate (eGFR) but was positively associated with the urinary albumin-to-creatinine ratio (uACR). However, the genus rectale_group was present in the IgAN group with a low abundance and was negatively associated with the uACR. Functional analysis disclosed that infection-related pathways were enriched in the IgAN group.

CONCLUSIONS

We demonstrate that gut microbiota dysbiosis occurs in patients with IgAN, and that changes in gut bacterial populations are closely related to IgAN clinical features, suggesting that certain specific gut microbiota may be a potential therapeutic target for IgAN.

Endothelial progenitor cell miR-126 promotes homing of endothelial progenitor cells within arterial thrombus in patients with cerebral infarction and its molecular mechanism

OBJECTIVE

The present study was designed to investigate the effect of microRNA-126 (miR-126) on the migration and homing of endothelial progenitor cells (EPCs) within arterial thrombus of cerebral infarction patients.

MATERIALS AND METHODS

EPCs from rat bone marrow were isolated, and miR-126 overexpressed EPCs were constructed by lentiviral transfection. Then, the middle cerebral artery occlusion (MCAO) model was established by the method of thread ligation. Successfully established model rats were randomly divided into miR-126 overexpression EPC group, miR-126 wild type EPC group, and normal saline group. One day after the infarction, the miR-126 overexpression EPCs, miR-126 wild type EPCs, and normal saline, were injected into the lateral ventricle of the corresponding groups. Also, the transplanted cells were tracked by cell dye SPDiIC18. The expression of tight junction proteins ZO-1 and Claudin-5 in brain tissue was detected by Western blotting.

RESULTS

Transplanted cells were detected in the cerebral infarction area 3 days after transplantation by cell dye SP-DiIC18. The number of homing EPCs in miR-126 overexpression group was significantly higher than that of miR-126 wild type EPC group (p < 0.05). Also, the protein expression of ZO-1 and Claudin-5 in the miR- 126 overexpression EPC group was significantly higher compared with that of the miR-126 wild type EPC group and the normal saline group.

CONCLUSIONS

miR-126 overexpression EPCs, which were transplanted in the lateral ventricle, can home to the cerebral infarction areas via increasing increase.

The clinical significance of plasma CFHR 1-5 in lupus nephropathy

A deficiency of complement factor H may lead to excessive consumption of C3 and an increase in C3b deposition, which are important pathological characteristics of lupus nephritis. Complement factor H-related proteins (CFHRs), comprising CFHR1 to CFHR5 (CFHR1-5), are members of the wider factor H/CFHR family. Their role in lupus nephritis remains unclear. In this study, we compared circulating levels of CFHR1-5 in 152 patients diagnosed with lupus nephritis and 20 unrelated healthy individuals to explore the relationship between the expression of CFHR1-5 and development of the disease. We found that plasma levels of CFHR3 and CFHR5 were higher in patients with lupus nephritis than in healthy individuals; also, CFHR3 and CFHR5 concentrations increased with increasing systemic lupus erythematosus disease activity index (SLEDAI) values (P < 0.05). Pearson's and Spearman's correlation test results confirmed that plasma CFHR3 and CFHR5 levels in lupus nephritis patients were positively correlated with proteinuria and levels of creatinine (Cr) and anti-dsDNA (correlation coefficients = 0.491-0.717, P < 0.05), while they were negatively correlated with plasma C3 levels and eGFR [correlation coefficients = -(0.706-0.788), P < 0.05]. Receiver operating characteristic (ROC) curve analysis results confirmed that plasma CFHR3 and CFHR5 levels were predictive of SLEDAI values and disease end points (area under the curve = 0.664-0.884, P < 0.05), with patients with both high CFHR3 and high CFHR5 exhibiting the shortest progression-free survival. Thus, both CFHR3 and CFHR5 are of prognostic value in lupus nephritis status.

Structure of A-C Type Intervariant Interface in Nonmodulated Martensite in a Ni-Mn-Ga Alloy

The structure of A-C type intervariant interface in nonmodulated martensite in the Ni54Mn25Ga21 alloy was studied using high resolution transmission electron microscopy. The A-C interface is between the martensitic variants A and C, each of which has a nanoscale substructure of twin-related lamellae. According to their different thicknesses, the nanoscale lamellae in each variant can be classified into major and minor lamellae. It is the boundaries between these lamellae in different variants that constitute the A-C interface, which is thus composed of major-major, minor-minor, and major-minor lamellar boundaries. The volume fraction of the minor lamellae, λ, plays an important role in the structure of A-C interfaces. For major-major and minor-minor lamellar boundaries, they are symmetrical or asymmetrical tilt boundaries; for major-minor boundary, as λ increases, it changes from a symmetrical tilt boundary to two asymmetrical microfacets. Moreover, both lattice and misfit dislocations were observed in the A-C interfaces. On the basis of experimental observations and dislocation theory, we explain how different morphologies of the A-C interface are formed and describe the formation process of the A-C interfaces from λ ≈ 0 to λ ≈ 0.5 in terms of dislocation-boundary interaction, and we infer that low density of interfacial dislocations would lead to high mobility of the A-C interface.

Norepinephrine and acetylcholine changes during electrically-induced atrial fibrillation episodes in canine models

Atrial fibrillation (AF) is the most prevalent heart rhythm disorder, and autonomic nervous system (ANS) is important to AF. This study aims to identify whether changes in transmitters released by ANS could reflect their activities. The right atrium (RA) groups (1-40V) included RA500 and RA1000. While ANS groups received high-frequency electrical stimulation (1-8V, 20 Hz, 2 ms), including left stellate ganglion stimulation (LSGS) andleft cervical vagus trunk stimulation (LVTS). The induced rate of AF, duration and atrial effective refractory period (AERP) were measured. The blood was drawn for evaluation of norepinephrine (NE) and acetylcholine (Ach) concentrations. At 12-hours, RA tissue was dissected and compared against un-stimulated controls. While AF was induced by all groups, duration and AERP were significantly different between RA pacing groups and ANS-stimulated groups, respectively (P&lt;0.05). Specific changes in profile of NE and Ach were associated with modality of stimulation. RA1000 tended to display most significant changes (P&lt;0.05) compared to other groups while variables concentration levels were observed in other groups. In conclusion, electrically-induced AF initiated by various modalities of stimulation showed different changes in serum and RA tissues. Fast frequency pacing caused significant atrial electrical remodeling, including ANS activity change.

[Changes of erythrocyte membrane ATPase activities and plasma lipids in patients with coronary heart disease]

Fasting plasma triglyceride (TG), total cholesterol(TC), low density lipoprotein-cholesterol(LDL-C), high density lipoprotein-cholesterol(HDL-C), activities of erythrocyte membrane Na(+)-K(+)-ATPase, Ca(2+)-ATPase, Mg(2+)-ATPase, and intraerythrocytic calcium concentration were examined in 21 patients with coronary heart disease(CHD) and 21 normal controls. It was found that the plasma contents of TG, TC, LDL-C and intraerythrocytic [Ca2+] in patients with CHD were much higher while plasma contents of HDL-C, activities of erythrocyte membrane Na(+)-K(+)- and Ca(2+)-ATPase were much lower than those of normal controls. Mg(2+)-ATPase activity showed no significant difference between these two groups. The activities of erythrocyte membrane Na(+)-K(+)- and Ca(2+)-ATPase were negatively correlated with plasma TG, TC, LDL-C levels, respectively, and positively correlated with plasma HDL-C. The possible pathogenic mechanism is discussed on the basis of our results.

Genome sequencing of a 239-kb region of rice chromosome 10L reveals a high frequency of gene duplication and a large chloroplast DNA insertion

In this study we describe a 239-kb region on the long arm of rice chromosome 10 that contains a high density (71%) of locally duplicated genes, including 24 copies of a glutathione S-transferase gene. Intriguingly, embedded within this cluster is a large insertion (approximately 33 kb) of rice (Oryza sativa) chloroplast DNA that is derived from two separate regions of the chloroplast genome. We used DNA fiber-based fluorescence in situ hybridization (fiber-FISH) analyses of O. sativa spp. japonica nuclei to confirm that the insertion of organellar DNA was not a cloning artifact. The sequence of the chloroplast insertion is nearly identical (99.7% identity) to the corresponding regions in the published rice chloroplast genome sequence, suggesting that the transfer event occurred recently. PCR amplification and sequence analysis in two subspecies of rice, O. sativa spp. japonica and spp. indica, indicates that the transfer event predated the divergence of these two subspecies. The chloroplast insertion is flanked by a 2.1-kb perfect direct repeat that is unique to this location in the rice genome.

[Analysis of the parkin gene deletion mutations in Chinese patients with Parkinson's disease]

OBJECTIVE

Clarify parkin gene deletion mutations at exons 3 to 7 in Chinese patients with Parkinson's disease (PD) and analyze them together with the clinical features of PD.

METHODS

DNA was extracted from peripheral blood of 33 sporadic PD patients and 6 familial PD patients. Deletion mutations of parkin gene were identified by PCR amplification and agarose gel electrophoresis. The clinical data were analyzed together with the above information.

RESULTS

Of the 33 sporadic PD patients, 1 had exons 5 and 7 deletion, 2 had exon 7 deletion. The age of onset was 46, 48, 50 respectively. In the 6 familial PD patients, 1 had exon 5 deletion. The inheritance pattern in this patient was autosomal recessive and onset of the patient was 60. All of the patients who had parkin gene deletion mutations had tremor, rigidity and bradykinesia, but athetosis was not found. In addition, deletion mutations of parkin gene at exons 3, 4 and 6, were not found.

CONCLUSION

There are deletion mutations of parkin gene at exons 5 and 7 in Chinese PD patients.

Effect of thinking on intracranial blood flow velocities

OBJECTIVE

To determine the effect of thinking on intracranial blood flow velocities.

METHODS

Transcranial Doppler (TCD) was used to measure the blood flow velocities of the cerebral arteries, when 10 normal persons were at rest and during thinking.

RESULTS

The mean flow velocities (MFVs) of the cerebral arteries during thinking were significantly higher than those at rest, especially in the MCA and ACA. The MFVs were raised from between 10.3% to 14.3%.

CONCLUSIONS

Thinking can increase the blood flow velocities of cerebral arteries significantly.

Gene expression profiling in human fetal liver and identification of tissue- and developmental-stage-specific genes through compiled expression profiles and efficient cloning of full-length cDNAs

Fetal liver intriguingly consists of hepatic parenchymal cells and hematopoietic stem/progenitor cells. Human fetal liver aged 22 wk of gestation (HFL22w) corresponds to the turning point between immigration and emigration of the hematopoietic system. To gain further molecular insight into its developmental and functional characteristics, HFL22w was studied by generating expressed sequence tags (ESTs) and by analyzing the compiled expression profiles of liver at different developmental stages. A total of 13,077 ESTs were sequenced from a 3'-directed cDNA library of HFL22w, and classified as follows: 5819 (44.5%) matched to known genes; 5460 (41.8%) exhibited no significant homology to known genes; and the remaining 1798 (13.7%) were genomic sequences of unknown function, mitochondrial genomic sequences, or repetitive sequences. Integration of ESTs of known human genes generated a profile including 1660 genes that could be divided into 15 gene categories according to their functions. Genes related to general housekeeping, ESTs associated with hematopoiesis, and liver-specific genes were highly expressed. Genes for signal transduction and those associated with diseases, abnormalities, or transcription regulation were also noticeably active. By comparing the expression profiles, we identified six gene groups that were associated with different developmental stages of human fetal liver, tumorigenesis, different physiological functions of Itoh cells against the other types of hepatic cells, and fetal hematopoiesis. The gene expression profile therefore reflected the unique functional characteristics of HFL22w remarkably. Meanwhile, 110 full-length cDNAs of novel genes were cloned and sequenced. These novel genes might contribute to our understanding of the unique functional characteristics of the human fetal liver at 22 wk.

Sorption and diffusion behavior of Cs and Sr on Jih-Hsing bentonite

Sorption and diffusion are important processes for the transport of radionuclides through buffer materials such as bentonite. In this study, the sorption and diffusion behaviors of Cs and Sr on Jih-Hsing bentonite are investigated using batch and through-diffusion techniques. The distribution coefficients (Kds) of Cs and Sr from batch experiments are approximately 1200 ml/g and 800 ml/g, respectively. It is found that the Freundlich isotherm model could fit the sorption isotherm with an equilibrium concentration of 10(-7)-10(-1) N. The calculated retardation factors (Rds) for samples at densities of 1.8 g/cm3, 2.0 g/cm3 and 2.2 g/cm3 are 5685, 7744, and 11000 for Cs, and are 3790, 5162, and 7334 for Sr. For the through-diffusion experiments on the compacted samples with the same densities, the corresponding apparent diffusion coefficients for Cs are (2.83+/-0.75) x 10(-13) m2/s, (1.97+/-0.02) x 10(-13) m2/s, and (1.91+/-0.12) x 10(-13) m2/s, respectively. The corresponding apparent diffusion coefficients for Sr are (1.33+/-0.13) x 10(-13) m2/s, (1.51+/-0.15) x 10(-13) m2/s, and (1.34+/-0.10) x 10(-13) m2/s. The Rds obtained from the diffusion experiments for sample densities of 1.8 g/cm3, 2.0 g/cm3 and 2.2 g/cm3 are 1166+/-355, 2113+/-123, 2796+/-171 for Cs, and 713+/-258, 510+/-68, 846+/-158 for Sr. It appears that the retardation factors obtained from the diffusion experiments are about one order of magnitude lower than those derived from the batch experiments. The discrepancy and the possible explanations are discussed in the paper.

[Analysis of amino acids, vitamins and inorganic elements in Dictyophora indusiata]

Fifteen amino acids(total content: 13.37 mg.100 ml-1), 12 inorganic elements(Zn 37.3 micrograms.g-1, Mn 56.9 micrograms.g-1, Cr 4.88 micrograms.g-1, Fe 370 micrograms.g-1, Se 0.81 microgram.g-1, Cu 28.2 micrograms.g-1, Co 0.78 microgram.g-1, Ni 2.09 micrograms.g-1, etc.), and vitamin E(73.2 micrograms.g-1) in Dictyophora indusiata were determined. Seven amino acids, including valine 0.61, leucine 1.04, isoleucine 0.66, threonine 0.74, methionine 0.20, lysine 0.52, and pheuylalanine 0.64(mg.100 mg-1), were found to be essential. The possible medical significance of Dictyophora indusiata is discussed.

Frequency of SCA1, SCA2, SCA3/MJD, SCA6, SCA7, and DRPLA CAG trinucleotide repeat expansion in patients with hereditary spinocerebellar ataxia from Chinese kindreds

OBJECTIVE

To assess the frequency of SCA1 (spinocerebellar ataxia type 1), SCA2, SCA3/MJD (spinocerebellar ataxia type 3/Machado-Joseph disease), SCA6, SCA7, and DRPLA (dentatorubropallidoluysian atrophy) CAG trinucleotide repeat expansions [(CAG)n] among persons diagnosed with hereditary SCA from Chinese families.

PATIENTS AND METHODS

Spinocerebellar ataxia type 1, SCA2, SCA3/MJD, SCA6, SCA7, and DRPLA (CAG)n mutation were detected with the polymerase chain reaction, highly denaturing polyacrylamide gel electrophoresis, and silver staining technique in 167 patients with autosomal dominant SCA from 85 Chinese families and 37 patients with sporadic SCA.

RESULTS

Spinocerebellar ataxia type 1 (CAG)n mutation in 7 patients from 4 kindreds (4.70%) was expanded to 53 to 62 repeats. Spinocerebellar ataxia type 2 (CAG)n mutation in 12 patients from 5 kindreds (5.88%) was expanded to 42 to 47 repeats. Spinocerebellar ataxia type 3/Machado-Joseph disease (CAG)n mutation in 83 patients from 41 kindreds (48.23%) was expanded to 68 to 83 repeats. Sixty-five patients from 35 kindreds (41.19%) and 37 patients with sporadic SCA did not test positive for SCA1, SCA2, SCA3/MJD, SCA6, SCA7, or DRPLA. There was a predictable inverse relationship between the number of CAG repeats and the age at onset for SCA3/MJD and SCA2. Clinically, dementia and hyporeflexia were more frequent in patients with SCA2, while spasticity, hyperreflexia, and Babinski signs were more frequent in patients with SCA3/ MJD, and those might be helpful in clinical work to primarily distinguish patients with SCA3/MJD and SCA2 from others with different types of SCA.

CONCLUSIONS

The frequency of SCA3/MJD is substantially higher than that of SCA1 and SCA2 in patients with autosomal dominant SCA from Chinese kindreds, who are non-Portuguese. Clinical expressions of the various types of SCAs overlap one another; therefore, for clinical study it is important to make a gene diagnosis and genetic classification for patients with SCA.

Detection of gastric slow wave propagation from the cutaneous electrogastrogram

The gastric slow wave is originated in the proximal stomach and propagates distally toward the pylorus. It determines the maximum frequency and propagation of gastric contractions. The aim of this study was to detect the propagation of the gastric slow wave from the surface electrogastrogram (EGG). The study was performed in 11 healthy subjects of normal weight. Gastric myoelectrical activity was recorded for 1 h in the fasting state with the use of a specially designed multichannel recording device that was composed of four identical amplifiers with cutoff frequencies of 1.8 and 16.0 cycles/min. Four active electrodes were placed on the abdomen along the gastric axis and were connected to a common reference electrode placed near the xiphoid process, yielding four-channel bipolar EGG signals. Cross-covariance analysis was performed to compute the time lag among the four channels. There was a time lag in EGG waveform between channels 1 and 4 (9.6 +/- 1.1 s); the average time during which the time lag was observed (>/=3 s) was 89.9 +/- 9.0%. There was a significant difference in the time lag among different adjacent channels (P < 0.04); the time lag observed between channels 3 and 4 was significantly smaller than that between channels 1 and 2 (P < 0.03). No correlation was found between the body mass index and the time lag between channels 1 and 4 (r = -0.31, P = 0.3). It was concluded that, with a multichannel recording device with identical multiamplifiers and an appropriate arrangement of abdominal electrodes, the propagation of the gastric slow wave could be identified from the EGG in healthy subjects. This method may be used to detect the coupling of the gastric slow wave noninvasively.

Promoter analysis of the cap8 operon, involved in type 8 capsular polysaccharide production in Staphylococcus aureus

The production of type 8 capsular polysaccharide (CP8) in Staphylococcus aureus is regulated in response to a variety of environmental factors. The cap8 genes required for the CP8 production in strain Becker are transcribed as a single large transcript by a primary promoter located within a 0.45-kb region upstream of the first gene of the cap8 gene cluster. In this study, we analyzed the primary cap8 promoter region in detail. We determined the transcription initiation site of the primary transcript by primer extension and identified the potential promoter sequences. We found several inverted and direct repeats upstream of the promoter. Deletion analysis and site-directed mutagenesis showed that a 10-bp inverted repeat of one of the repeats was required for promoter activity. We showed that the distance but not the specific sequences between the inverted repeat and the promoter was critical to the promoter activity. However, insertion of a DNA sequence with two or four helix turns in this intervening region had a slight effect on promoter activity. To demonstrate the biological significance of the 10-bp inverted repeat, we constructed a strain with a mutation in the repeat in the S. aureus Becker chromosome and showed that the repeat affected CP8 production mostly at the transcriptional level. By gel mobility shift assay, we demonstrated that strain Becker produced at least one protein capable of specific binding to the 10-bp inverted repeat, indicating that the repeat serves as a positive regulatory protein binding site. In addition, reporter gene fusion analysis showed that the cap8 promoter activity was influenced by various growth media and affected most by yeast extract. Our results suggest that yeast extract may exert its profound inhibitory effect on cap8 gene expression through the 10-bp inverted repeat element.

Neuronal degeneration in canine narcolepsy

Narcolepsy is a lifelong illness characterized by persistent sleepiness, hypnagogic hallucinations, and episodes of motor paralysis called cataplexy. We have tested the hypothesis that a transient neurodegenerative process is linked to symptom onset. Using the amino-cupric silver stain on brain sections from canine narcoleptics, we found elevated levels of axonal degeneration in the amygdala, basal forebrain (including the nucleus of the diagonal band, substantia innominata, and preoptic region), entopeduncular nucleus, and medial septal region. Reactive neuronal somata, an indicator of neuronal pathology, were found in the ventral amygdala. Axonal degeneration was maximal at 2-4 months of age. The number of reactive cells was maximal at 1 month of age. These degenerative changes precede or coincide with symptom onset. The forebrain degeneration that we have observed can explain the major symptoms of narcolepsy.

Selective determination of a group of organic compounds in complex sample matrixes by LC/MIMS with on-line immunoaffinity extraction

An on-line immunoaffinity extraction with liquid chromatography/membrane introduction mass spectrometry (IAE/LC/MIMS) method for the determination of BTEX compounds in complex sample matrixes is described. This method uses an immunoaffinity column (1 mm i.d. x 20 mm) for on-line sample cleanup and enrichment, a 5-micron C18 trapping column (2 mm i.d. x 20 mm) for analyte focusing, a 3-micron C18 analytical column (3.2 mm i.d. x 100 mm) for separation, and a membrane introduction mass spectrometer for quantitation. The immunoaffinity column was evaluated in terms of binding capacity, recovery, and enrichment factor. The method was optimized for the determination of BTEX compounds in a mixture of 30 volatile organic compounds, which showed no matrix interference and a dramatic improvement of the detection limit over that of the LC/MIMS method (up to 474-fold). This method was also used for the determination of BTEX compounds in several gasoline-contaminated water samples, and the results were compared with the EPA reference methods.

A dual coordinate system finite difference method for forward and inverse solutions of the volume conductor problem in neurology

Finite difference methods for the volume conductor problem have used a single coordinate system for the mesh and made approximations of Laplace's equation. This method is simple but has two major problems. Firstly, to deal with boundary conditions properly, the normal potential gradient at the boundary must be known. However it is complicated to compute at a curved surface point. Secondly, for an inverse solution the equation on a curved boundary is difficult to reverse since more than one inner mesh node appears in the approximation equation for each surface point. The new method developed in this paper is a dual coordinate system. One system serves as a frame mesh, the other is a sub-coordinate system in which surface points become mesh points (regular nodes). The equation at each surface point is then directly reversible since only one inner point appears in the equation. The forward solution is applied to both centric and eccentric bone models and uses the conventional successive over-relaxation (SOR) method. Noise is added to this solution for input to the inverse procedure which is a direct step-in non-iterative method. Low pass filtering was effective in reducing the effects of noise. In the examples given, only one coordinate subsystem is used but, for complex shape boundaries, multiple subsystems would be necessary.

Transcriptional analysis of type 1 capsule genes in Staphylococcus aureus

Serotype 1 capsule of Staphylococcus aureus plays an important role in staphylococcal infections. A 14.6 kb chromosomal DNA fragment containing 13 cap1 genes responsible for the synthesis of type 1 capsule in S. aureus strain M has been previously cloned and sequenced in our laboratory. These genes are closely linked and are transcribed in one orientation. To study the transcription of these genes, we employed genetic complementation using a set of plasmids with various deletions in the 14.6 kb region to complement mutants mapped in each of the 13 genes. We found that there were six transcriptional units. By Northern hybridization using the entire gene cluster as a probe, we identified a large 14 kb band and several smaller bands ranging from 0.3 to 6 kb. The 14 kb band was also identified by various individual gene probes, suggesting that all 13 genes are transcribed into a large transcript. The 14 kb transcript and the smaller bands were not detected when a 533 bp fragment containing the potential promoter region upstream of the first gene (cap1A) was deleted from the chromosome, suggesting that the small transcripts are the degradation (processing) products of the 14 kb transcript. The activities of the promoters identified by genetic complementation tests were quantitatively measured by transcriptional fusions using xylE as the reporter gene. The result showed that the promoter preceding the first cap1 gene was 45-198-fold higher than the downstream promoters. The result from gene-fusion studies is in agreement with the Northern analysis in that only the transcript transcribed from the first promoter was detected. Taken together, these results suggest that the cap1 genes are organized as a large operon with at least five weak internal promoters, and the long polycistronic transcript is processed (degraded) into several smaller transcripts. The transcription initiation site of the primary transcript was mapped by S1 nuclease mapping and the major promoter was defined by deletion analysis of the promoter-xylE fusion. In addition, we showed that the internal promoters, despite their weak activities, were sufficiently effective at expressing their downstream genes required for producing capsule, compared to the wild-type strain.

[Dynamic changes of amino acids in extracellular fluid in rat hippocampus in cases of cerebral ischemia]

OBJECTIVE

To study the changes of excitatory amino acid (EAA) in patients with cerebral ischemia.

METHODS

We observed dynamic changes of EAA in extracellular fluid by intracerebral microdialysis inserted in hippocampus through stereotaxic method with modified Pulsinelli's model of four vessels occlusion.

RESULTS

The concentration of Glu was 5.88 +/- 1.40 and 11.2 +/- 1.5 micromol/L in patients with incomplete cerebral ischemia after 30 minutes and 60 minutes, and the concentration of Asp was 2.72 +/- 0.24 and 4.4 +/- 0.6 micromol/L. The concentration of Glu was 15.1 +/- 1.6 micromol/L and 17.9 +/- 1.6 micromol/L in patients with complete cerebral ischemia after 30 minutes and 60 minutes, and the concentration of Asp was 8.2 +/- 1.0 and 12.1 +/- 1.1 micromol/L. The concentration of Glu and Asp was 1.75 +/- 0.88 micromol/L and 0.24 +/- 0.09 micromol/L in the controls.

CONCLUSIONS

In this study, the concentration of Glu and Asp in patients with cerebral ischemia was significantly increased than in the controls, and the more serious ischemia was, the more release of EAA. It is suggested that Dansen injection can reduce the release of EAA by cerebral cells in case of ischemia.

Rhythmic expression of Fos-related proteins within the rat suprachiasmatic nucleus during constant retinal illumination

Within the retinorecipient or ventrolateral subfield of suprachiasmatic nuclei (SCN) in rodents, expression of the protein product of the c-fos proto-oncogene, Fos, is regulated by light. In the present study, the expression of Fos and Fos-related proteins within the SCN was examined immunocytochemically for evidence of rhythmic variation in rats sacrificed at different circadian times during exposure to constant retinal illumination (LL). In all animals, nuclear Fos immunoreactivity was mainly confined to an area of the SCN that was coextensive with neuropeptide Y-immunopositive fibers distinguishing the ventrolateral subfield of the nucleus. Moreover, Fos-immunostaining within the ventrolateral SCN of rats exposed to LL fluctuated over the course of the circadian cycle, such that the density of immunopositive cells within this subfield was 2 times greater during the subjective night than during the subjective day. Since Fos expression within the SCN oscillates in the absence of photoperiodic time cues and since the peak of this oscillation coincides with the circadian times when light modulates the periodicity of the SCN pacemaker, these data provide further evidence that expression of the c-fos gene may be a molecular signal in the circadian timekeeping mechanism in the SCN and its regulation by photic stimuli.

Monoamine metabolites in cerebrospinal fluid during and after acute cerebral ischemia

In order to understand the role of monoamines in cerebral ischemia, 3-methoxy-4-hydroxyphenylglycol(MHPG), 5-hydroxyindoleacetic acid (5-HIAA), and homovanillic acid(HVA), the three major unconjugated monoamine metabolites in cerebrospinal fluid (CSF), of 33 patients and 18 controls were measured with high performance liquid chromatography. Results showed all three metabolites were raised in patients with severe ischemia, but only MHPG and 5-HIAA were elevated significantly, MHPG changes more quickly and regularly as a consequence of cerebral ischemia than the two others. A positive correlation between any pair of metabolites was found in controls and in patients in the first week after stroke, but not at the end of the second week. Computer assisted multivariate analysis indicated 5-HIAA and MHPG correlated more closely with the state of illness in the acute stage, whereas HVA correlated the least. Possible explanations for the changes of CSF levels of amine metabolites are discussed.

Serum cholesterol, its lipoprotein fractions among survivors of cerebrovascular disease. A case-control study

A case-control study was conducted in 1983 on 210 cerebrovascular disease (CVD) patients identified from a retrospective cross-sectional door-to-door survey of four cities in the People's Republic of China. One hundred and eleven male (mean age 63.8 +/- 8.9 years) and 99 female (mean age 63.5 +/- 11.1 years) CVD survivors and controls matched for sex, age, race and area were selected. Total serum cholesterol, high-density lipoprotein and low-density lipoprotein cholesterol were measured to see if there were differences between lipids in survivors of CVD and their matched controls. There was a higher level of total cholesterol in cerebral thrombotic patients (n = 114) and a lower level of total cholesterol and high-density lipoprotein cholesterol in cerebral hemorrhagic patients (n = 35) than in controls, although the results were not statistically significant. The only higher level of total serum cholesterol that might be important was in the group of male thrombotic patients of age greater than 70 years (n = 22; nominal p value less than 0.05). The implication of this finding needs further clarification.