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L J Jin

Publications and source records attributed to L J Jin.

At least 37 records · Page 2Linked to original sources
PubMed1999

Indirect laser-induced fluorescence detection of valproic acid in human serum by capillary electrophoresis.

A capillary electrophoresis (CE) method with indirect laser-induced fluorescence detection for the analysis of valproic acid in human serum has been explored. The buffer system was optimized with 2.5 mM borate-phosphate at pH 8.4; fluorescein sodium was used to generate background signal at a concentration of 6 microM. Hexanoic acid was selected as internal standard. Serum sample was deproteinized by acetonitrile. Analysis was performed by direct injection of the supernatant. CE separation was carried out at 30 kV and the total analysis time was less than 15 min, including sample treatment and electrophoresis time. No interference from other common anticonvulsant drugs occurred under the experimental conditions used. The interference of human serum matrix was reduced by using a high ratio of acetonitrile to serum (minimum 5:1) for deproteinization. Interference of ionic components in serum could occur, depending on the sample source. The linear range of concentrations for standard drug was between 4.5-144.0 microg/mL (r = 0.9947). The limit of detection was 0.9 microg/mL at S/N > or = 3; the limit of quantitation at S/N > or = 20 was 3 microg/mL. The recoveries of valproic acid spiked into serum were 69.2% and 60.2% for concentration levels of 90 and 54 microg/mL, respectively. This CE method was shown to be successful in the analysis of valproic acid in standard solutions. However, interference from the matrix was observed in the analysis of this compound in serum samples. Additional work should be done to develop a highly selective sample preparation technique.

Buffers↗
PubMed1999

Screening of carbohydrates in urine by capillary electrophoresis.

Carbohydrate analysis of urine is clinically important in assisting diagnosis of disorders of carbohydrate metabolism and understanding its pathologic significance. Paper chromatography and thin-layer chromatography are the techniques that are often employed for the determination of urinary carbohydrates. An aim of our experiments was to investigate the utility of capillary electrophoresis to develop a fast screening procedure of urinary carbohydrates. Simultaneous resolution of eight carbohydrates involving maltose, lactose, D-mannose, D-glucose, D-ribose, D-xylose, L-arabinose and D-galactose as markers was obtained with 130 mM borate (pH 10.2). Ethanol/water (80/20 v/v) and acetonitrile proved to be efficient reagents for urine sample clean-up which produced symmetrical peaks. The urine sample from a normal subject was determined to contain lactose, glucose, xylose and arabinose that fall within normal ranges of these carbohydrates in urine. The investigations made in this study may be potentially useful in carbohydrate screening, especially in neonatal urine screening.

Carbohydrates↗
PubMed1999

Granulocyte elastase activity and PGE2 levels in gingival crevicular fluid in relation to the presence of subgingival periodontopathogens in subjects with untreated adult periodontitis.

This study aimed to determine the association between the levels of granulocyte elastase and prostaglandin E2 (PGE2) in GCE and the concomitant presence of periodontopathogens in untreated adult periodontitis (AP). GCF and subgingival plaque were sampled by paper strips and paper points respectively, from various periodontal sites in 16 AP subjects. Granulocyte elastase activity in GCF was analyzed with a low molecular weight substrate specific for granulocyte elastase, pGluProVal-pNA, and the maximal rate of elastase activity (MR-EA, mAbs/min/site) was calculated. PGE2 levels in GCF were determined by radioimmunoassay. 5 species-specific DNA probes were used to detect the presence of A. actinomyceterncomitans (A.a., ATCC 43718), B. forsythus (B.f, ATCC 43037), P. gingivalis (P.g., ATCC 33277), P. intermedia (P.i., ATCC 33563), and T. denticola (T.d., ATCC 35405), with a sensitivity of 10(3) cells/paper point. No A.a. was detectable from all sites sampled. The predominant combination of species detected was B.f., P.g., P.i. & T.d. and it was significantly higher at periodontitis sites (68%) than at healthy (7%) or gingivitis sites (29%) (p<0.05). Overall, MR-EA values were strongly correlated with PGE2 levels (r=0.655, p<0.001), especially at these periodontitis sites co-infected by B.f., P.g., P.i. & T.d. (r=0.722, p<0.001). The periodontitis sites co-infected by the 4 species were observable from 15 subjects. These sites were sub-grouped into 8 subjects with a high MR-EA and 7 subjects with a low MR-EA. The PGE2 levels in the high MR-EA group were significantly higher than in the low MR-EA group (p<0.05). No significant differences in clinical or bacterial data were found between the two groups. While within the high MR-EA group, similar results were found between the paired periodontitis sites in each subject with highest and lowest MR-EA values. This study shows that the local host response to bacterial challenge in untreated periodontal pockets is diverse in terms of the intensity of inflammatory response measured by granulocyte elastase and PGE2 levels in GCE A more thorough evaluation of the risk for active periodontal disease may involve the combined approaches to the test of the dynamic bacteria-host relations.

Adult↗
PubMed1999

Longitudinal effect of non-surgical treatment and systemic metronidazole for 1 week in smokers and non-smokers with refractory periodontitis: a 5-year study.

BACKGROUND: Periodontitis consists of a mixture of diseases, most of which respond favorably to traditional mechanical therapy. It is now recognized that advanced periodontitis does not always respond to conventional management with scaling, periodontal surgery, and oral hygiene measures. However, various types of antibiotics given systemically or locally improve the success rate of periodontal therapy. In short-term studies, it has been shown that metronidazole, when systemically administered after debridement, resulted in treatment benefits including less need for surgical intervention. METHODS: In this double-blind study, we evaluated periodontal treatment involving initial non-surgical treatment, systemic administration of metronidazole for 1 week, and then follow-ups for scaling and root planing every 6 months, for 5 years. The study population consisted of 64 subjects (37 smokers and 27 non-smokers), mean age 36.3 (+/-3.0 SD) years, with severe periodontal disease. After initial scaling and root planing, patients were randomly assigned to the intervention or placebo groups: 400 mg metronidazole or a placebo administered at 8-hour intervals for 1 week. The participants underwent an extensive clinical periodontal examination. Gingival crevicular fluid (GCF) was analyzed for spirochetes and granulocytes. Samples were cultured for Actinobacillus actinomycetemcomitans (A.a.), Porphyromonas gingivalis (Pg.), and Prevotella intermedia (Pi.). RESULTS: The number of patients infected with A.a., Pg., Pi., and spirochetes decreased during the study. Most patients who harbored spirochetes at the end of the study had these microorganisms at the beginning. Smokers responded less favorably to periodontal therapy than non-smokers. Non-smoking patients who required only non-surgical therapy in the intervention group showed statistically significant improvement in the clinical parameters after 5 years. Patients with complete healing, defined as the absence of inflamed sites > or =5 mm, after 5 years were found only in the intervention group. The patients considered healthy after 5 years were the same patients found to be healthy after 6 months. CONCLUSIONS: Decisive factors in the sustained long-term improvement of patients who respond satisfactorily to treatment are probably initial scaling and root planing; a brief course of metronidazole; and regular follow-up examinations at 6-month intervals for oral hygiene and scaling and root planing.

Adult↗
PubMed1998

Comparison of chiral recognition capabilities of cyclodextrins for the separation of basic drugs in capillary zone electrophoresis.

The enantiomeric separation of some racemic anti-histamines and anti-malarials, namely (+/-)-pheniramine, (+/-)-brompheniramine, (+/-)-chlorpheniramine, (+/-)-doxylamine, and (+/-)-chloroquine, was investigated by capillary zone electrophoresis. The enantiomeric separation of five compounds was obtained by addition of approximately 7 mM (1%, w/v) sulfated-beta-cyclodextrin into the buffer as a chiral selector. The effects of sulfated-beta-cyclodextrin concentration and buffer pH on migration and resolution are discussed. Two other cyclodextrins, carboxyethylated-beta-cyclodextrin and hydroxypropyl-beta-cyclodextrin were also investigated. Four of the racemic compounds were resolved using 14 mM (2%, w/v) carboxyethylated-beta-cyclodextrin while 28 mM (4%, w/v) hydroxypropyl-beta-cyclodextrin resolved only two of them. It was found that the type of substituent and the degree of substitution on the rim of the CD structure played an important role in enhancing the chiral recognition. Cyclodextrins with negatively charged substituents and higher degree of substitution on the rim of the structure proved to give better resolution to the cationic racemic compounds compared with cyclodextrin with neutral substituents. This is due to the countercurrent mobility of the negatively charged cyclodextrin relative to the cationic analytes thus allowing for a smaller difference in interaction constants to achieve a successful resolution of enantiomers. Furthermore, lower concentrations of negatively charged cyclodextrins were necessary to achieve the equivalent resolutions as compared with the neutral ones.

2-Hydroxypropyl-beta-cyclodextrin↗
PubMed1998

Subgingival microbiota of shallow periodontal pockets in individuals after head and neck irradiation.

This study aimed at investigating the subgingival plaque microorganisms of shallow pockets (< or = 5 mm) in subjects who previously received irradiation in the head and neck region for treatment of nasopharyngeal carcinoma. Direct microscopy and anaerobic culture were used. Subgingival paper point samples were taken from 6 tooth-sites (one/sextant) per subject for direct microscopy (n = 108). Another set of paper points was taken from the deepest of the previously selected sites (one per subject) with: group A) no bleeding on probing to the sulcus depth (n = 9) and group B) bleeding on probing to the sulcus depth (n = 6) for microscopic and anaerobic culture study. Under the microscope, the microflora was found to be a complex mixture comprising gram-positive and gram-negative cocci, rods and filaments, fusiforms, curved rods and spirochetes. Low level of fungi were observed and mycelia were occasionally detected. There was no significant variation in the plaque bacterial morphotypes observable according to sites of isolation and no significant difference between group A and group B in morphotypes of the different microflora. The predominant cultivable microflora comprised several species of facultative and obligate anaerobic bacteria: Gemella, Peptostreptococcus, Staphylococcus, Stomatococcus, Streptococcus, Actinomyces, Eubacterium, Lactobacillus, Propionibacterium, Neisseria, Veillonella, Bacteroides, Campylobacter, Capnocytophaga, Fusobacterium, Kingella, Porphyromonas and Prevotella species. There was no difference between the two groups except the significantly higher proportion of Kingella dentrificans isolated from group B sites. However, colonization of the gingival sulcus in these individuals by microbes that are normal flora of: skin (Peptostreptococcus prevotii and Propionibacterium granulosum) and gut (Eubacterium aerofaciens, Fusobacterium mortiferum and Fusobacterium varium) was detected. These findings appear to suggest that the major components of the subgingival microflora of shallow sites in previously head- and neck-irradiated individuals are similar to that of gingivitis sites in the normal population although they may contain bacterial or fungal species uncommon in normal subjects.

Adult↗
PubMed1998

Quality of life and personality in adults with epilepsy.

PURPOSE: This study was undertaken to understand the quality of life, personality, and associated factors in patients with epilepsy. METHODS: 117 patients with epilepsy and 84 healthy people were studied and tested using the Social Support Scale, the General Well-being Schedule, the Life-Event Scale, the Behavior Pattern Scale, and the Eysenck Personality Questionnaire (EPQ). RESULTS: There were no significant differences between the patients with epilepsy and the control group in the Social Support Scale results. The General Well-being Schedule scores were lower for the case patients than for the control group (p < 0.01). Scores for patients with frequent seizures (once a month or more) were lower than those without frequent seizures (less than once per month). The case patients had higher negative scores in the family-related problem section of the Life Events Scale, compared with the control group (p < 0.05). The patients with epilepsy were also more likely to lie (p < 0.05); their emotions were more changeable (p < 0.01), and their character more introverted (p < 0.05), although their behavior patterns were similar to the controls. We also studied associated factors related to personality, general well-being, and familial-negative life-events. CONCLUSIONS: These results provide information about patients with epilepsy that may be useful in their psychological treatment.

Adult↗
PubMed1998

Adjunctive orthodontic treatment of periodontally involved teeth: case reports.

Elongated and spaced incisors are common in patients suffering from severe periodontal disease. Intrusion and uprighting of incisors might be the logical solution for this problem. This article describes a team approach to treatment planning for adult patients with severe localized periodontitis accompanied by marginal bone loss and spacing and elongation of incisors. The treatment involves the combination of periodontal treatment, orthodontic intrusion, and prosthetic therapy. Controlled intrusion in two patients led to a decrease in the clinical crown length, better access for oral hygiene procedures, better gingival form, and a more suitable distribution of occlusal forces.

Adult↗
PubMed1995

Granulocyte elastase in gingival crevicular fluid: improved monitoring of the site-specific response to treatment in patients with destructive periodontitis.

In 13 patients with severe destructive periodontitis, the response to periodontal therapy was estimated by granulocyte elastase level in gingival crevicular fluid (GCF). 62 sites were classified according to changes of probing depths (PD) and quantitative bone height (BH%) before and after 5-year regular maintenance treatment: (i) 17 consistently healthy sites with no changes of PD and BH%; (ii) 6 initially healthy sites with deterioration in PD and BH%; (iii) 14 diseased sites with improvement in PD and BH%; (iv) 25 diseased sites with no improvement in PD and BH%. GCF was collected by an intracrevicular washing system. The released elastase in the supernatants (EA-S) and the cell-bound elastase in the pellets (EA-P) were determined with a low molecular weight substrate specific for granulocyte elastase. The ratio of EA-S and EA-P (S/P-ratio) was used as a relative measure of elastase released by the granulocytes present. The sites classified as diseased with no improvement or initially healthy but deteriorating, had significantly higher EA-S, EA-P and S/P-ratios than the consistently healthy sites or diseased but improving sites (p < 0.01). Both EA-S and S/P-ratio showed strongly positive correlations with the current levels of gingival inflammation and periodontal destruction (p < 0.001). The present study suggests that increased elastase level is associated with disease progression, and may be used to monitor the response to longitudinal maintenance therapy.

Adult↗
PubMed1995

Variations in crevicular fluid elastase levels in periodontitis patients on long-term maintenance.

Granulocyte elastase was determined in the gingival crevicular fluid (GCF) of 18 periodontitis patients. They initially had similar severity of disease but had responded differently to 5-yr maintenance, 13 responders and 5 non-responders. A total of 102 sites were investigated and categorized as: i) consistently healthy, ii) healthy after treatment, iii) gingivitis, and iv) periodontitis, according to clinical criteria. GCF elastase activity was determined with a granulocyte-specific substrate. The sites from non-responders had consistently higher elastase levels than the corresponding category of sites from responders, despite similar gingival inflammation and periodontal destruction, with the exception of consistently healthy sites. Within the non-responders, the periodontitis sites had higher elastase levels than the gingivitis sites commensurate with probing depth, while no difference existed between gingivitis sites and sites healthy after treatment, despite a difference in probing depth. In contrast, in the responders similar elastase levels were found at the periodontitis sites and gingivitis sites despite difference in probing depth, while both diseased sites had higher elastase levels than the sites healthy after treatment, commensurate with probing depth. This study suggests that increased granulocyte-specific elastase levels in GCF may serve as a diagnostic marker for refractory periodontitis patients.

Adult↗
PubMed1995

A longitudinal investigation of the individual consistency of plaque levels in adults.

The present investigation was designed to determine the individual variation of plaque levels in adults over a period of 3 months. The participants were 20 healthy subjects, 11 men and 9 women, with a mean age of 42.3 +/- 7.3(SD) years. Plaque area was determined with a computerized image analysis system and expressed as percentage of tooth area (P% Index). The scoring procedures were carried out three times (tests 1, 2, and 3) at an interval of 4 weeks. After each test all plaque was removed. All subjects were instructed to maintain their personal oral hygiene habits during the study. The results showed no significant differences for the means of P% Index between tests 1, 2, and 3 in the whole mouth, upper and lower jaws, right and left sides, or each tooth surface. The intraindividual plaque levels for individual tooth surfaces were closely correlated between tests 1, 2 and 3. The intraindividual plaque level was consistent in tests 1, 2, and 3 with standard deviations within subjects ranging from 1.1% to 6.2%. This study suggests that individual plaque levels seem to be consistent on the basis of tooth surface over a certain period of time. Individual plaque control should be more directed towards tooth surfaces with comparably high plaque accumulation within the mouth for significant reduction of the overall plaque levels.

Adult↗
PubMed1995

Clinical characteristics of destructive periodontitis in a risk group of Swedish urban adults.

An initial screening investigation of 1681 Swedish urban adults aged 31-40 years with untreated periodontitis showed that 17.2% (289) had at least one site with probing depth > or = 5 mm. The 289 subjects were offered a complete clinical examination and treatment. 144 subjects, 85 men and 59 women, agreed to participate and 145 were non-responding subjects and used as a drop out sample. The results from the screening data showed that the attendants had poorer oral hygiene status and more severe periodontitis than the drop out subjects. The present report describes clinical data of this representative sample with adult periodontitis. Clinical indices were recorded and bone height (BH%) for all teeth was measured with a computer digitizing system. In the 144 attendants, Plaque Index was > 1 in 56.2%, Calculus Index was > 1 in 57.0%, Gingival Index was > 1 in 97.2% and bleeding on probing was found in 89.1% of the sites. 11.1% of the subjects had 1-3 teeth with probing depth > or = 5 mm, 59.0% 4-10 teeth, 25.7% 11-20 teeth and 4.2% > 20 teeth. 47.9% of the subjects had mean BH% less than 80. 45.1% of the subjects had at least one site with an intrabony defect, of which 20% had 3-4 sites and 27.7% > or = 5 sites. It is concluded that advanced generalized periodontitis exists in a limited number of 31-40 year-olds in Sweden. Specific risk factors may be involved in the pathogenesis of the disease.

Adult↗
PubMed1994

Periodontal status in an urban adult population in Sweden.

The purpose was to describe the current periodontal status in a Swedish urban population aged 31-40 yr. 1681 individuals, 840 men and 841 women, participated in the study. 68.5% of the subjects had low amount of plaque, 82.8% low level of calculus and 28.9% healthy gingiva or mild gingivitis. 82.8% of the subjects had no pockets with probing depth (PD) > or = 5 mm. 4.9% of the subjects had one tooth with PD > or = 5 mm, 6.7% 2-5 teeth, 2.4% 6-9 teeth and 3.2% > or = 10 teeth with pockets. 55.8% of the subjects had no missing teeth, third molars excluded. 16.5% had one tooth missing, 23.8% 2-5 teeth, 2.7% 6-9 teeth and 1.2% > or = 10 teeth. 8.6% of the subjects had at least one front tooth missing, 28.7% one premolar and 24.1% one molar missing. Men had significantly higher scores than women for plaque (DI-S), calculus (CI-S), gingivitis (GI-M), and number and percent of remaining teeth with PD > or = 5 mm. Smokers had significantly higher scores than non-smokers for DI-S, CI-S, GI-M, number and percent of remaining teeth with PD > or = 5 mm, and number of missing teeth. The individuals who visited the dentist every year had better oral hygiene and gingival status than those who attended for > 3 yr. The multiple regression analysis showed that calculus (P = 0.0001) smoking (P = 0.001), and dental visits (P = 0.0284) were significantly correlated to the number of teeth with PD > or = 5 mm.

Adult↗
PubMed1993

DNA probe detection of periodontopathogens in advanced periodontitis.

Species-specific DNA probes were used to determine the presence of Actinobacillus actinomycetemcomitans (A.a.), Porphyromonas (Bacteroides) gingivalis, Prevotella intermedia, Treponema denticola, Eikenella corrodens, Fusobacterium nucleatum, and Wolinella recta in subgingival plaque from deep pockets/sites of patients with advanced periodontitis. The subjects were 20 patients with severe adult periodontitis, 13 men and 7 women (mean age 45.6 +/- 6.7 yr). For each subject, 9-10 subgingival sites with the deepest probing depths from each quadrant were sampled by the paper point method, a total of 198 sites, with mean probing depth 7.2 +/- 1.6 mm and clinical attachment level 9.5 +/- 2.7 mm. A.a. was present in at least one site in 75% of the subjects; P. gingivalis was found in 95%; P. intermedia and W. recta were found in 90%, respectively; and T. denticola, E. corrodens, and F. nucleatum were found in all subjects. In the 198 samples, A.a. was detected in 25.8%, P. gingivalis in 51.5%, P. intermedia in 64.1%, T. denticola in 60.6%, E. corrodens in 72.9%, F. nucleatum in 74.7%, and W. recta in 65.7%. The predominant combination was the simultaneous presence of P. intermedia, T. denticola, E. corrodens, F. nucleatum, and W. recta in 89.5% of the subjects and 46.8% of the sites. Of these sites, 51.1% showed the combined presence of P. gingivalis and 28.4% that of both A.a. and P. gingivalis. None of the seven bacteria could be detected in 14.4% of the total sites sampled. The present study indicates that severe destructive adult periodontitis is a multibacterial infection and that certain combinations of periodontopathogens seem to be important in the pathogenesis of the disease.

Adult↗