Protective effect of resveratrol on nickel-refining fumes-induced inflammatory damage

Nickel (Ni), a ductile and hard silver-white transition metal, is commonly found in occupational environments and can harm the human body. Since it is a toxic compound, long-term Ni exposure can cause pneumonia, rhinitis, and other types of respiratory inflammatory diseases. Resveratrol (Res) is a plant antitoxin polyphenol, which also has anti-cancer and anti-inflammatory properties. In this report, the toxicity of Ni-refining fumes on the human lung bronchial epithelial (BEAS-2B) cells, as well as the protective effects of Res were investigated in vitro, and the specific mechanism of its anti-inflammatory effect was explained. The experimental observations of this study revealed that Ni-refining fumes induce BEAS-2B cell damage, increase reactive oxygen species (ROS) content, activate NLRP3 (LRR-, NOD-, and pyrin domain-containing 3) inflammasome, and promote the secretion of the cytokine Interleukin (IL)-1β, leading to cellular inflammation and reducing cell activity. Resveratrol (20 μmol/L) activated sirtuin 1 (SIRT1) in BEAS-2B cells to increase protein and mRNA expression. SIRT1 was observed to inhibit the transcriptional activity of nuclear factor-kappaB (NF-κB), reduced the expression of NLRP3 protein and mRNA, and inhibited NLRP3 inflammation. The level of inflammasome activation and IL-1β overexpression could reduce the inflammatory damage caused by the Ni-refining fume particles on the BEAS-2B cells and exert anti-inflammatory protective effects. In vivo experiments further confirmed that resveratrol could effectively alleviate the acute inflammatory injuries caused due to exposure to the Ni-refining fume particles in the lung tissues of the Wistar rats, and verified that resveratrol could exert its anti-inflammatory impact through the SIRT1-NF-κB-NLRP3 pathway. These results provide an important theoretical basis for developing novel protective drugs and investigating the mechanism of action for inflammatory injury in occupational populations caused by exposure to nickel and other heavy metals.

Stimulating the expression of sphingosine kinase 1 (SphK1) is beneficial to reduce acrylamide-induced nerve cell damage

Sphingosine kinase 1 (SphK1) is an important signaling molecule for cell proliferation and survival. However, the role of SphK1 in acrylamide (ACR)-induced nerve injury remains unclear. The purpose of this study was to investigate the role and potential mechanism of SphK1 in ACR-induced nerve injury. Liquid chromatography triple quadrupole tandem mass spectrometry (LC-MS/MS) and reverse transcription-quantitative PCR (RT-qPCR) were used to detect sphingosine 1-phosphate (S1P) content in serum and SphK1 content in whole blood from an occupational work group exposed to ACR compared to a non-exposed group. For in vitro experiments, SphK1 in human SH-SY5Y neuroblastoma cells was activated using SphK1-specific activator phorbol 12-myristate 13-acetate (PMA). Our research also utilized cell viability assays, flow cytometry, western blots, RT-qPCR and related protein detection to assess activity of the mitogen activated protein kinase (MAPK) signaling pathway. The results of the population study showed that the contents of SphK1 and S1P in the ACR-exposed occupational contact group were lower than in the non-exposed group. The results of in vitro experiments showed that expression of SphK1 decreased with the increase in ACR concentration. Activating SphK1 improved the survival rate of SH-SY5Y cells and decreased the apoptosis rate. Activating SphK1 in SH-SY5Y cells also regulated MAPK signaling, including enhancing the phosphorylation of extracellular signal-regulated protein kinases (ERK) and inhibiting the phosphorylation of c-Jun N-terminal kinase (JNK) and p38. These results suggest that activating SphK1 can protect against nerve cell damage caused by ACR.

A retrospective comparative study of local anesthesia only and local anesthesia with sedation for percutaneous endoscopic lumbar discectomy

It is still an unsolved problem to achieve both immediate intraoperative feedback and satisfactory surgical experience in percutaneous endoscopic lumbar discectomy under local anesthesia for lumbar disk herniation (LDH) patients. Herein, we compared the analgesic and sedative effects of local anesthesia alone and local anesthesia with conscious sedation in LDH patients during percutaneous endoscopic lumbar discectomy. Ninety-two LDH patients were enrolled and divided into the following groups: control group (Con Group), dexmedetomidine group (Dex Group), oxycodone group (Oxy Group), and dexmedetomidine + oxycodone group (Dex + Oxy Group). Various signs, including mean arterial pressure (MAP), heart rate (HR), pulse oximeter oxygen saturation (SpO₂) and Ramsay score, were compared before anesthesia (T1), working cannula establishment (T2), nucleus pulposus removal (T3), and immediately postoperation (T4). Clinical outcomes, including VAS score, operation time, hospitalization period, Macnab criteria, and SF-36 score, were also evaluated. The Dex + Oxy Group showed the most stable MAP and HR at T2 and T3 in all groups. The clinical outcomes, such as VAS, hospitalization period, Macnab criteria, and SF-36 score, have no significant differences among groups (p > 0.05). Local anesthesia combined with conscious sedation is a safe and effective method to improve the surgical experience and achieve satisfying clinical outcomes for LDH patients during percutaneous endoscopic lumbar discectomy.

[Evaluation of tumor vascular normalization in colorectal cancer mouse mode induced by recombinant human endostatin by intravoxel incoherent motion diffusion-weighted magnetic resonance imaging]

Objective: To evaluate the feasibility of intravoxel incoherent motion diffusion-weighted magnetic resonance imaging (IVIM-DWI MRI) in the evaluation of tumor vascular normalization in a mouse model of colorectal cancer induced by recombinant human endostatin (rhES). Methods: The CT26 colorectal cancer xenograft model of BALB/c mice were established and divided into rhES group and control group, with 20 mice in each group. The mice of rhES group were intravenously injected with rhES 5 mg·kg(-1)·d(-1) once daily for 12 days, while the mice of the control group were intravenously injected with the same volume of 0.9% saline. 5 mice of rhES group and control group were randomly selected to perform IVIM-DWI MRI as following times: before treatment and four, eight, twelve days after treatment. The parameters of IVIM-DWI were recorded, including true diffusion coefficient(D), pseudo-diffusion coefficient (D(*)) and perfusion fraction (f). Meanwhile, microvessel density (MVD), pericyte coverage and tumor perfusion in tumor tissues were detected by immunofluorescence, respectively. Results: The tumor volumes of control group and rhES group before treatment were (154.42±24.65) mm(3) and (174.24±28.27)mm(3,) respectively, without statistically significant difference (P=0.440). From day 2 to day 12 after treatment, the tumor volume of rhES group was significantly smaller than that of control group (all P<0.05). There were no statistical significances of D value between the rhES group and control group before and after treatment (all P>0.05). The D(*) values of the rhES group were (10.940±2.834)×10(-3)mm(2)/s and (12.940±2.801)×10(-3)mm(2)/s in day 4 and 8 after treatment respectively, significantly higher than (6.980±1.554)×10(-3)mm(2)/s and (7.898±1.603)×10(-3)mm(2)/s of control group (P<0.05). Moreover, compared with control group, the D(*) value of rhES group was significantly lower in day 12 (6.848±1.460)×10(-3)mm(2)/s vs (9.950±2.596)×10(-3)mm(2)/s, (P<0.05). The f value of rhES group in day 8 was (0.226±0.021)%, significantly higher than (0.178±0.016)% of control group (P<0.01). The MVD of rhES group was significantly lower than that of control group (P<0.05), while the pericyte coverage and tumor perfusion of rhES group were significantly higher than those of control group in day 4 and 8 after treatment (all P<0.05). In addition, we found D(*) value of IVIM-DWI in rhES group was significantly related with MVD, pericyte coverage and tumor perfusion (r=-0.354, r=0.555, r=0.559, all P<0.05). Meanwhile, the f value in rhES group was also significantly related with MVD, pericyte coverage and tumor perfusion (r=-0.391, r=0.538, r=0.315, all P<0.05). Conclusions: IVIM-DWI MRI can effectively evaluate the vascular normalization in rhES-induced CT26 colorectal tumor.The parameters D(*) and f are closely related to intratumorally microvessel density, pericyte coverage and perfusion, which can effectively monitor the occurrence of tumor vascular normalization time.

Nickel-smelting fumes induce mitochondrial damage and apoptosis, accompanied by decreases in viability, in NIH/3T3 cells

Nickel (Ni) is widely present in the occupational environment and causes various adverse effects on the human body. Apoptosis induced by Ni²⁺ may be a key mechanism underlying its toxic effect. In the present study, we investigated the effect of Ni-smelting fumes on cell viability, mitochondrial damage, and apoptosis-related proteins in NIH/3T3 cells. The effects of Ni-smelting fumes at concentrations of 0, 25, 50, and 100 μg/mL were tested. Treatment with Ni-smelting fumes for 24 h and 48 h significantly decreased cell viability and lactate dehydrogenase activity in a dose- and time-dependent manner compared with the blank control group. Exposure to Ni-smelting fumes increased mitochondrial permeability transition pore opening in a dose-dependent manner and decreased mitochondrial membrane potential and the activity of the mitochondrial respiratory chain complexes I, II, and IV. The fumes significantly downregulated Bcl-2, procaspase-9, and procaspase-3 and upregulated Bax, caspase-9, and caspase-3 (P < 0.05). Ni-smelting fumes caused significant cytotoxicity, oxidative stress, mitochondrial damage, and apoptosis through the intrinsic pathway in mammalian cells. The present paper provides hypotheses and experimental support for these hypotheses that Ni-smelting fumes cause cytotoxicity through the mechanism of inducing mitochondrial damage and apoptosis in NIH/3T3 cells.

Effect and Safety of TNF Inhibitors in Immunoglobulin-Resistant Kawasaki Disease: a Meta-analysis

Previous studies showed that tumor necrosis factor (TNF) inhibitors might decrease the rate of coronary artery abnormalities in pediatrics with intravenous immunoglobulin (IVIG)-resistant Kawasaki disease (KD). Therefore, we aimed to evaluate the effect and safety of TNF inhibitors in IVIG-resistant KD. We undertook a meta-analysis of clinical trials identified in systematic searches of PubMed, EMBASE, Cochrane Database, and Google scholar through May 2016. Five studies were included. Overall, rate of coronary artery aneurysm was comparable between groups (relative risk (RR), 1.05; 95 % confidence interval (95 % CI), 0.60 to 1.81; P = 0.87). No significant differences were recorded between groups in coronary artery Z scores (standardized mean difference (SMD), 0.27; 95 % CI, -0.30 to 0.85; P = 0.35). Meanwhile, TNF inhibitors were not associated with a significant decreased risk of treatment resistance compared with IVIG treatment (RR, 0.65; 95 % CI, 0.37 to 0.15; P = 0.14). However, days of fever was significantly reduced in the TNF inhibitor group (SMD, -0.66; 95 % CI, -0.90 to -0.41; P < 0.001). Additionally, risk of serious adverse events was similar between groups. Therefore, TNF inhibitors could shorten the duration of fever in IVIG-resistant KD. However, TNF inhibitors appear to have no cardioprotective effect in patients with IVIG-resistant KD.

Cardiac μ-opioid receptor contributes to opioid-induced cardioprotection in chronic heart failure

BACKGROUND

The therapeutic potential of cardiac μ-opioid receptors in ischaemia-reperfusion (I/R) injury during opioid-modulating diseases, such as heart failure, is unknown. We aimed to explore the changes of cardiac μ-opioid receptor expression during heart failure, and its role in opioid-induced cardioprotection.

METHODS

Rats received doxorubicin (DOX) or were subjected to coronary artery ligation to induce heart failure, or received normal saline (NS) as control. Hearts from NS or DOX rats were isolated and subjected to myocardial ischaemia and reperfusion in an in vitro perfusion system. The opioid [D-Ala,²N-MePhe,⁴ Gly-ol]-enkephalin (DAMGO), with a high μ-opioid receptor specificity, morphine, and remifentanil were administrated before I/R with or without opioid receptor antagonists, or an extracellular signal-regulated kinase (ERK) inhibitor.

RESULTS

Cardiac μ-opioid receptor mRNA concentrations were 3.2 times elevated in DOX-treated rats compared with NS rats, while cardiac μ-opioid receptor protein concentrations showed 6.1- and 3.5-fold increases in DOX-treated and post-infarcted rats, respectively. DAMGO reduced I/R-caused infarct size, expressed as the ratio of area at risk, from 0.50 (0.04) to 0.25 (0.03) in failing rat hearts, but had no effect on infarct size in control hearts. DAMGO promoted phosphorylation of ERK and glycogen synthase kinase (GSK)-3β only in failing hearts. DAMGO-mediated cardioprotection was blocked by an ERK inhibitor. The μ-opioid receptor antagonist D-Pen-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP) prevented morphine- and remifentanil-induced cardioprotection and phosphorylation of ERK and GSK-3β in failing hearts. In contrast, δ- and κ-opioid receptor selective antagonists were less potent than CTOP in the failing hearts.

CONCLUSIONS

Cardiac μ-opioid receptors were substantially up-regulated during heart failure, which increased DAMGO-induced cardioprotection against I/R injury.

[Identification of Y-chromosomal Genetic Types for the Soldier's Remains from Huaihai Campaign]

OBJECTIVES

To identify the Y-chromosomal genetic types for the soldier's remains from Huaihai Campaign, and to offer a clue for search of their paternal relatives.

METHODS

DNA of the remains were extracted by the ancient DNA extraction method. Yfiler kit was used for the multiplex amplification of 17 Y-STR loci. The haplogroups of the samples were speculated. Detailed genotyping of the selected Y-SNP was performed based on the latest Y-chromosome phylogenetic tree. Haplotype-sharing analysis was done based on the data of Y-SNP and Y-STR, the closest modern individual information to the genetic relationship of remains was gained.

RESULTS

A total of 8 Y-STR haplotypes were observed on 17 Y-STR loci of 8 male individuals. Furthermore, 6 Y-SNP haplogroups were identified, which were O2a1-M95+, O1a1-P203+, O3*-M122+/M234-, D1-M15+, C3*-ST and R1a1-M17+.

CONCLUSIONS

Identification of Y-chromosomal genetic types for the soldier's remains from Huaihai Campaign shows a reference value on inferring the geographical origins of old materials.

Metabolomics analysis of serum from subjects after occupational exposure to acrylamide using UPLC-MS

Since occupational exposure to acrylamide (ACR) may cause nerve damage, sensitive biomarkers to evaluate the early effects of ACR on human health are needed. In the present study, we have compared a group of individuals with occupational exposure to ACR (contact group, n = 65) with a group of individuals with no exposure (non-contact group, n = 60). Serum metabolomics analysis of the contact and non-contact groups was carried out using ultra performance liquid chromatograph/time of flight mass spectrometry, combined with multivariate analysis, to identify potential metabolites. Serum biochemical indexes of the contact and non-contact groups were also determined using an automatic biochemistry analyzer. There was a clear separation between the contact group and the non-contact group; receiver operator characteristic curve analysis suggested that phytosphingosine, 4E,15Z-bilirubin IXa and tryptophan were the best metabolites to use as biomarkers. Liver function was also found to be abnormal in the contact group. Important, ACR-related, metabolic changes were seen in the contact group and new biomarkers for assessing the toxicity of ACR on the central nervous system have been proposed. This study will provide a sound basis for exploring the toxic mechanisms and metabolic pathways of ACR.

Identification and cloning of GOLDEN2-LIKE1 (GLK1), a transcription factor associated with chloroplast development in Brassica napus L

Photosynthesis is the process by which dry matter accumulates, which affects rapeseed yield. In this study, we identified GOLDEN2-LIKE1 (GLK1), located on chromosome A07 and 59.2 kb away from the single nucleotide polymorphism marker SNP16353A07, which encodes a transcription factor associated with the rate of photosynthesis in leaves. We then identified 96 GLK1 family members from 53 species using a hidden Markov model (HMM) search and found 24 of these genes, which were derived from 17 Brassicaceae species. Phylogenetic analysis showed that 24 Brassicaceae proteins were classified into three subgroups, named the Brassica family, Adenium arabicum, and Arabidopsis. Using homologous cloning methods, we identified four BnaGLK1 copies; however, the coding sequences were shorter than the putative sequences from the reference genome, probably due to splicing errors among the reference genome sequence or different gene copies being present in the different B. napus lines. In addition, we found that BnaGLK1 genes were expressed at higher levels in leaves with more chloroplasts than were present in other leaves. Overexpression of BnaGLK1a resulted in darker leaves and siliques than observed in the control, suggesting that BnaGLK1 might promote chloroplast development to affect the rate of photosynthesis in leaves. These results will help to elucidate the mechanism of chloroplast biogenesis by GLK1 in B. napus.

Expression of transforming growth factor-β1 in neonatal rats with hyperoxia-induced bronchopulmonary dysplasia and its relationship with lung development

The aim of this study was to detect the expression of transforming growth factor-ß1 (TGF-ß1) in neonatal rats with hyperoxia-induced bronchopulmonary dysplasia (BPD) and to explore its relationship with lung development. Forty-eight rats (2-3 days old) were randomly divided into a hyperoxia group and a control group (N = 24) which were then fed in ≥95% oxygen atmosphere and air, respectively. On the 1st, 3rd and 7th days of hyperoxia exposure, morphological changes of lung tissues were observed under an optical microscope. TGF-ß1 mRNA and protein levels in lung tissues were detected by real-time quantitative polymerase chain reaction and western blot, respectively. With increasing time of hyperoxia exposure, the hyperoxia group gradually suffered from pathological changes such as poor development of lung tissues, alveolar simplification, decrease in the number of alveoli, and hindered pulmonary microvascular development. On the 7th day of hyperoxia exposure, TGF-ß1 mRNA and protein levels (relative to b-actin) of the hyperoxia group (0.34 ± 0.19 and 0.21 ± 0.09, respectively) were significantly lower than those of the control group (0.83 ± 0.45 and 0.57 ± 0.45, respectively; P < 0.05). TGF-ß1 participates in the pathogenesis of BPD as an important regulatory factor during pulmonary vascular development.

[Nickel smelting dust exposures to NIH/3T3 cellular mitochondrial damage and L-ascorbic acid interference effect]

OBJECTIVE

To study the protection of L-ascorbic acid on mouse embryonic fibroblasts (NIH/3T3) from carcinogenic effects caused by nickel smelting smoke subjects.

METHODS

The NIH/3T3 cells were divided into experimental and L-ascorbic acid in the intervention group. Plus exposure group concentration of nickel refining dusts were formulate 0.00, 25.00, 50.00, 100.00 μg/ml suspension, the intervention group on the basis of the added exposure group containing L-ascorbic acid (100 mmol/L) , contacted. Then, the cell viability was detected by MTT assay, we used Calcein-AM fluorescence probe to detect cell mitochondrial permeability transition pore (MPTP) changes, JC-1 staining to observe and detect the cell mitochondrial membrane potential (MMP) change, colorimetric quantitative to study the activity of mitochondrial respiratory chain complex Ⅰ,Ⅱ,Ⅲ,Ⅳ.

RESULTS

Upon 24 h incubation, both cell relative inhibition rate, openness of MPTP were increasing enhanced by different concentrations, on the other hand, MMP and the activity of mitochondrial respiratory chain complexⅠ, Ⅱ, Ⅳ were obviously decreased, the differences were statistically significant (P<0.05) .After L-ascorbic acid intervention treatment, the results of the intervention group were lower than that of the exposure group, and the difference was statistically significant (P<0.05) , indicating the protection of L-ascorbic acid on cell mitochondrial from the nickel exposure damage.

CONCLUSION

The damage effects of nickel on NIH/3T3 cell mitochondrial was significantly enhanced with the increasing concentration, and L-ascorbic acid has certain protection on cellular mitochondrial.

Screening of differentially-expressed genes in the muscles of rabbit breeds with expression profile chip

The molecular mechanism underlying muscle development in rabbits is not well-understood. In the current study, differentially-expressed genes were scanned using an expression profile chip in New Zealand white rabbits (introduced breed) and Fujian yellow rabbits (local breed), and some of the genes were tested using reverse transcription-polymerase chain reaction. The amplification results were consistent with the microarray data. Fourteen and 13 genes involved in muscle development were identified in the dorsal longissimus and leg muscles, respectively. Myh6, Myh7, Myh7b, Myo5b, Tnnc1, Tpm3, and Acta2 were scanned in the longissimus and leg muscles. Thus, these genes may be involved in muscle fiber formation and muscle development in rabbits. This study provides a theoretical basis for improving meat quality, as well as for the future development and utilization of local meat rabbit breeds.

High frequency occurrence of 1-OPRD variant of PRNP gene in gastric cancer cell lines and Chinese population with gastric cancer

The prion protein gene PRNP encodes PrPc and PrPsc, causing a number of neurological disorders. Approximately 10-15% of human prion disease is inherited and more than 20 pathogenic mutations have been found. Most of the genetic alterations are point mutations, with the exception of genetic insertions of one to nine extra octapeptide repeats occurring in the important octapeptide-coding region. Our previous work showed that PrPc was overexpressed in gastric cancer. We wondered whether mutations of PrPc existed in human gastric cancer. DNA sequencing and gel electrophoresis were used to determine the possible mutation of PrPc in patients and cell lines of gastric cancer. We found that 1-OPRD (one octapeptide-repeat deletion) homozygosity or heterozygosity exists in several gastric cancer cell lines, e.g. MKN28 and KatoIII are homozygous for 1-OPRD, and SGC7901 and BGC-823 are heterozygous for 1-OPRD. The mutation frequency in tissues of gastric cancer cases is significantly higher than that in the common population (p<0.05). All positive cases in gastric cancer were found to be heterozygous for 1-OPRD. Further study of the variant may be helpful in understanding the mechanisms of occurrence and development of clinical gastric carcinoma as well as the biology of the mysterious gene PRNP.

Overexpression of PrPC and its antiapoptosis function in gastric cancer

Cellular prion protein (PrP(C)), a glycosylphosphatidylinositol-anchored membrane protein, was found in our lab to be widely expressed in gastric cancer cell lines. In order to evaluate its biological significance in human gastric cancer, we investigated its expression in a large series of gastric tissue samples (n = 124) by immuno histochemical staining with the monoclonal antibody 3F4. Compared with normal tissues, gastric adenocarcinoma showed increased PrP(C) expression, correlated with the histopathological differentiation (according to the WHO and Lauren classifications) and tumor progression (as documented by pTNM staging). To better understand the underlying mechanism, we introduced the PrP(C) and two pairs of RNAi into the poorly differentiated gastric cancer cell line AGS and found that PrP(C) suppressed ROS and slowed down apoptosis in transfected cells. Further study proved that the apoptosis-related protein Bcl-2 was upregulated whereas p53 and Bax were downregulated in the PrP(C)-transfected cells. A reverse effect was observed in PrP(C) siRNA-transfected cells. These results strongly suggested that PrP(C) might play a role as an effective antiapoptotic protein through Bcl-2-dependent apoptotic pathways in gastric cancer cells. Further study into the mechanism of these relationships might enrich the knowledge of PrP, better our understanding of the nature of gastric carcinoma, and further develop possible strategies to block or reverse the development of gastric carcinoma.

Fluorescence from airborne microparticles: dependence on size, concentration of fluorophores, and illumination intensity

We measured fluorescence from spherical water droplets containing tryptophan and from aggregates of bacterial cells and compared these measurements with calculations of fluorescence of dielectric spheres. The measured dependence of fluorescence on size, from both droplets and dry-particle aggregates of bacteria, is proportional to the absorption cross section calculated for homogeneous spheres containing the appropriate percentage of tryptophan. However, as the tryptophan concentration of the water droplets is increased, the measured fluorescence from droplets increases less than predicted, probably because of concentration quenching. We model the dependence of the fluorescence on input intensity by assuming that the average time between fluorescence emission events is the sum of the fluorescence lifetime and the excitation lifetime (the average time it takes for an illuminated molecule to be excited), which we calculated assuming that the intensity inside the particle is uniform. Even though the intensity inside the particles spatially varies, this assumption of uniform intensity still leads to results consistent with the measured intensity dependence.

Temporal changes of cerebral metabolites and striatal lesions in acute 3-nitropropionic acid intoxication in the rat

To investigate the mechanisms of neuronal death in neurodegeneration, in vivo localized proton magnetic resonance spectroscopy ((1)H-MRS) and diffusion-weighted MRI (DWI) were used to evaluate temporal changes in rat striata after administration of 3-nitropropionic acid. It was found that N-acetylaspartate (NAA) reduction, with nearly simultaneous evidence of striatal lesions in DWI, was preceded by a significant and progressive increase of acetate. Shortly before the NAA levels decreased to the lowest point, acetate levels peaked and began to gradually decline toward the control levels. These results suggest that acetate increase may arise from fatty acid degradation, inhibition of succinate dehydrogenase and possible NAA hydrolysis. The elevated acetate may provide a source of acetyl group for membrane repair during excitotoxic brain injury. Magn Reson Med 44:29-34, 2000.

Two-dimensional angular optical scattering patterns as droplets evolve into clusters

Remarkable changes in the two-dimensional angular optical scattering (TAOS) pattern are observed when an acoustically levitated water droplet with inclusions evolves into a dry aggregate. The emergence of polystyrene latex sphere inclusions near the droplet surface has a clear effect on the TAOS. A speckle pattern in the TAOS replaces the continuous contours associated with Mie scattering from a smooth droplet. Once the contours break up, this speckle pattern persists as the levitated droplet evaporates, making the transition from a droplet with inclusions to a dried aggregate. The initial emergence of the speckle pattern is observed for an inclusion volume fraction near 8%.

Single-shot fluorescence spectra of individual micrometer-sized bioaerosols illuminated by a 351- or a 266-nm ultraviolet laser

Reproducible fluorescence spectra of individual 2- to 5-microm -diameter biological aerosol particles excited with a single shot from a Q -switched laser (266 or 351 nm) have been obtained with highly improved signal-to-noise ratios. Critical to the advance are crossed diode-laser trigger beams, which precisely define the sample volume, and a reflecting objective, which minimizes chromatic aberration and has a large N.A. for collecting fluorescence. Several allergens (red oak, meadow oat pollen, paper mulberry pollen, and puffball spores) have different fluorescence spectra. Bacillus subtilis fluorescence spectrum deteriorates at high 266-nm incident intensity. Dry riboflavin particles illuminated with a 351-nm light exhibit a new 420-nm fluorescence peak that grows nonlinearly with laser pulse energy.

Asian students change their eating patterns after living in the United States

OBJECTIVE

To collect information on changes in dietary patterns among Asian students before and after immigration to the United States.

DESIGN

A questionnaire designed to collect information about background, changes in food habits, and frequency of food consumption from a 72-item food list was mailed to subjects.

SUBJECTS/SETTING

Potential participants were students of local universities and junior colleges who were born in China, Taiwan, Hong Kong, Japan, or Korea and were aged 18 years or older. All subjects were required to have been residing in the United States for at least 3 months before the start of the study. Questionnaires were mailed to 120 potential participants.

STATISTICAL ANALYSIS

Paired t tests were used to determine differences in eating patterns and frequency of food consumption of subjects before and after immigrating to the United States.

RESULTS

Seventy-one questionnaires were returned. Because of missing information on 8 of these questionnaires, only 63 were used in the analysis, which gave a response rate of 53%. The number of students consuming only 2 meals per day increased significantly; 29 (46%) respondents skipped breakfast because of their school schedules. Despite no significant change in the frequency of snack consumption, a majority (n = 46; 73%) of the respondents were consuming more salty and sweet snack items. Subjects were eating out less often, but they were selecting more American-style fast foods when they did eat out. Significant increases were noted in consumption of fats/sweets, diary products, and fruits, and significant decreases were noted in the consumption of meat/meat alternatives and vegetables after immigration to the United States.

APPLICATIONS/CONCLUSIONS

Results of this study could be useful to dietetics practitioners as they observe changes in dietary patterns of Asian immigrants. These health professionals can use this information to plan nutrition education programs for Asian groups so that they can make informed decisions in adapting to new eating patterns and make wise food choices in their new environment. It is important to help Asian immigrants retain healthful food habits from their original country and to encourage them to choose eating patterns of the new culture that are nutritionally sound.

Function of GABA rho1 receptors is up-regulated by chronic GABA treatment in Xenopus oocytes

This study was aimed to investigate the effect of chronic gamma-aminobutyric acid (GABA) treatment on homomeric GABA rho1 receptors expressed in Xenopus oocytes. The rho1 mRNA-injected oocytes were incubated with 10 mM GABA for 2, 6, 24, 48 or 72 h, prior to the assessment of GABA-gated ion currents. The results showed that GABA exposure for more than 6 h dramatically enhanced the peak GABA-activated currents. In addition to current amplitude, the apparent GABA potency and cooperativity were significantly increased. The enhancement reached its plateau after a 24-h exposure. The up-regulation of GABA current amplitude was completely inhibited by cycloheximide, a translation inhibitor. This suggests that chronic GABA treatment may increase the translational activity of GABA rho1 subunit in Xenopus oocytes.

Leprosy control in Shandong Province, China, 1955-1983; some epidemiological features

A comprehensive leprosy control program was launched in Shandong Province, People's Republic of China, in 1955, with the establishment of the Provincial Skin Disease Control Institute and a network of Skin Disease Control Stations and leprosy hospitals at the county level. Through repeated different methods of case finding, dapsone monotherapy, and intensive follow up, incidence has decreased from 5.1 to 0.46/100,000 in 25 years. Findings such as the increase in the mean age at onset and in the lepromatous-to-tuberculoid ratio, and a general decline in the age-specific incidence in successive cohorts, are in concurrence with the findings in other countries where leprosy is disappearing.

Extraoral sagittal osteotomy of the mandibular ramus

A new type of extraoral sagittal osteotomy of the mandibular ramis and retromolar region is described. This is a simple and versatile procedure which may may be used in the correction of prognathism, retrognathism, open bite, and mandibular asymmetry. The procedure shares all the advantages of the intraoral sagittal osteotomy of the mandibular ramus and has several other advantages as well. A case is presented for illustration.