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[Research on the nonlinear model of near infrared spectroscopy and the total sugar of tobacco samples].

Near infrared spectroscopy (NIR) is an instrumental method applied for rapidly measuring the NIR spectra of pulverized tobacco samples and computing the chemical compositions from the spectral data. In the present paper, a mixed algorithm was employed for building the nonlinear model of NIR and the total sugar of tobacco samples. The mixed algorithm was combined with Partial Least Squares (PLS) method and Artificial Neural Network (ANN). The model based on the mixed algorithm was divided into two parts: linear part and nonlinear part, and the corresponding model of each part was built respectively. Compared with the classical multivariate calibration methods such as Principle Component Regression (PCR), PLS and nonlinear PLS (NPLS), the proposed procedure performed much better. The results showed that the mixed algorithm could be used for the quantitative analysis of the total sugar in tobacco samples.

Calibration↗

Human skin preserved in anhydric sodium chloride for months can be successfully transplanted.

Human skin can be preserved in pulverized sodium chloride dehydrated at 240C for 2 hours at room temperature for periods of weeks or months and successfully transplanted to scid mouse, retaining its normal morphological structure. Fragment of skin of a size of 10 x 10 x 6 mm were harvested during elective vascular and orthopaedic surgery of lower limbs, dried of blood and placed in anhydric sodium chloride powder in tight sealed containers. Prior to transplantation to scid mice, the specimens were desalinated and rehydrated. Specimes preserved for 1 to 6 months and harvested 3-4 weeks after transplantation revealed intensive incorporation of bromdeoxyuridine (BrdU) into basal keratinocytes. They expressed p63 and CD29 (stem cells, and transient cells antigens), PCNA (proliferating cell nuclear antigen) and cytokeratin 16 specific for proliferating keratinocytes. Dermal fibroblasts and few large HLA II cells showed a normal structure. Bacterial flora of skin did not change after grafting. We conclude that human skin can survive in a dehydrated state in sodium chloride for months and after transplantation the epidermal basal layer cells give rise to keratinocyte progenies. Skin fibroblasts and some resident immune cells can also survive.

Anhydrides↗

Evaluation of selected plants for their toxic effects in canaries.

Leaves or fruit from 14 plants considered to be toxic to pet birds were administered by gavage to 15 pairs of canaries (Serinus canaria). Each bird was given 0.12 to 0.70 g of plant material. One pair served as a control and was given distilled water. The plant materials were flash-frozen in liquid nitrogen, pulverized, and resuspended in deionized water for administration. Of the plants tested, 5 (oleander, lupine, foxglove, yew leaves, and dieffenbachia) were considered highly toxic and were associated with acute death of birds. The remaining plant samples caused no, or only transient, clinical illness.

Animals↗

Liquid chromatography/tandem mass spectrometry analysis of chloramphenicol in cooked crab meat.

A liquid chromatography/tandem mass spectrometry (LC/MS/MS) method is described for the extraction, cleanup, determination, and confirmation of chloramphenicol (CAP) in cooked crab meat. The method involves pulverization of cooked crab meat with dry ice; extraction of the CAP into ethyl acetate (EtOAc); evaporation (by N2) of the EtOAc; addition of methanol, aqueous NaCl, and heptane; extraction of the lipids into the heptane, followed by extraction of the aqueous phase with EtOAc; evaporation (by N2) of the EtOAc; dissolution into methanol-water; filtration; and separation/detection/confirmation using LC/MS/MS. Crab meat was fortified at 0.25, 0.50, and 1.0 ng/g (ppb) chloramphenicol. Average absolute recoveries were 67, 84, and 86%, respectively, with relative standard deviation values all less than 1%. Four daughter ions (m/z 152, 176, 194, and 257) were monitored off the m/z 321 precursor ion. Determination was based on a standard curve using the peak areas of the m/z 152 daughter ion (the base peak) for standard solutions equivalent to 0.10, 0.20, 0.50, and 1.0 ppb in tissue (made with control crab extract). A set of 6 matrix controls (unfortified crab meat) was also analyzed, in which no chloramphenicol was detected. For identification purposes, the ion ratios (of each daughter ion versus the base daughter ion) of the fortified crab versus those of the chloramphenicol standards agreed within 10% (relative) at fortified chloramphenicol concentrations of 0.25-1.0 ppb.

Acetates↗

[Study on extraction of coumarins in Cnidium monieri by supercritical CO2 and separation of compositions analysis].

OBJECTIVE: To analyze the chemical constituents of supercritical carbon dioxide extraction products from Cnidium monieri. METHOD: Four-factor and three-level orthogonal experimental design was used to optimize the SFE conditions as guided by the content of total coumarins in the extract. The chemical constituents were separated and identified by recrystalization. RESULT: Optimum extraction process was established: 25 MPa as extraction pressure, 50 degrees C as extraction temperature, 6.5 MPa as separation pressure and 60 degrees C as separation temperature. CONCLUSION: Changes in extraction pressure, temperature, time, pulverized degree and separation pressure affect the extracting results remarkably. The two kinds of chemical constituents were separated by recrystallization from C. monieri and identified by the methods of UV, IR, MS, NMR.

Chromatography, Supercritical Fluid↗

Diagnosis of Alzheimer's disease in an exhumed decomposed brain after twenty months of burial in a deep grave.

After 20 months of interment in a deep grave, the decomposed body of the 81-year old testator of a will was exhumed to sustain the burden of proof that he lacked testamentary capacity when the will was rewritten two days prior to his death. The brain was mushy and pulverized with complete disappearance of the brainstem, cerebellum and subcortical ganglia. Small foci of relatively intact dorsal frontal neocortex were identified. Sections from these foci were stained with hematoxylin and eosin, bielchowsky silver stain and immunostains for beta amyloid peptide (betaA4), tau and alpha-synuclein. Despite severe autolysis and decomposition, the bielchowsky stain and the betaA4 immunostains showed preserved frequent neuritic amyloid plaques with very few residual neurofibrillary tangles. Cerebral Amyloid Angiopathy was present. At the present time this case represents the first documented and reported case of direct tissue diagnosis of Alzheimer's Disease pathology in a decomposed brain following long term burial in a deep grave.

Aged, 80 and over↗

Holmium laser cystolithotripsy in children: initial experience.

INTRODUCTION: Management of vesical calculi in children poses an interesting challenge to the urologist. The treatment options currently available include open surgery, transurethral pneumatic cystolithotripsy, percutaneous suprapubic cystolithotomy and shockwave lithotripsy (SWL). Holmium: YAG (Ho: YAG) laser cystolithotripsy represents a novel modality of treatment that is minimally invasive. MATERIALS AND METHODS: From July 1999 to January 2003 we treated 23 children with vesical calculi using transurethral Ho: YAG laser lithotripsy. The indications for cystolithotripsy were stone size < or = 4 cm (N=19), or multiple stones with combined stone burden < or = 4 cm (N=4). The mean patient age was 7.8 (range 2-12) years and the mean stone size was 2.7 (range 0.9-4) cm. Access was obtained with an 8F ureteroscope and holmium laser energy (0.6-1.8 J/pulse at 5-12 Hz) was applied through a 550-mum. end-firing fibre under video guidance. The calculi were pulverized to tiny fragments about 2-3 mm in size. An 8F urinary catheter was placed for one night in all patients. Post-operatively the children were evaluated at 3 and 18 months with radiological imaging and uroflowmetry to confirm stone-free status and exclude urethral stricture formation. RESULTS: The mean duration of the endoscopic procedure was 38 (range 19-62) minutes while the mean length of hospital stay was 2.2 (range 2-3) days. All the children were rendered stone-free following a single operative session. Laser-induced major complications were not observed in any of the children. At the mean follow-up of 42 (range 26-69) months none of the children developed stone recurrence, urinary tract infections or urethral strictures. CONCLUSIONS: Transurethral Ho: YAG laser lithotripsy was found to be an efficient and safe modality for the treatment of vesical calculi in children.

Child↗

[RNA isolation from human embryonic tissues].

To investigate the method of RNA isolation from human embryonic tissues and the factors influencing the quality of RNA, the RNA from human embryonic tissues obtained with drug-induced labor or non-drug induced labor were isolated by using grind with liquid nitrogen or homogenizer without liquid nitrogen. The results showed that the positive rates of RNA integrity in grind with liquid nitrogen group and in homogenizer without liquid nitrogen group were 68.42% and 29.79% respectively, and there was significant difference between these two groups; however, there was no statistic difference in positive rate of RNA integrity, OD(260)/OD(280) ratio and beta-actin gene expression level between the drug-induced labor group and non-drug induced labor group. It is concluded that pulverize of tissue in liquid nitrogen remains the integrity of RNA isolated and may be applied for RNA isolation from human embryonic tissues. The quality of RNA is not affected by different methods of induction of maternal labor.

Embryo, Mammalian↗

[Evaluation of the fibrogenic effect of coke dust on the lungs and internal organs of experimental animals].

Based on the data collected by the Provincial Regional Administration Unit for Control of Epidemics and Hygiene in Katowice, dust concentration at the MAKOSZOWY Coking Plant in Zabrze at 18 work-places exceeded the TLV's. The purpose of this study was to determine changes within the respiratory systems of experimental animals exposed to intratracheal administration of MAKOSZOWY Coking Plant dust, sampled at the charging larry 3-4 operating stand and at the battery roof. After pulverization the dusts contained 98.1% and 99.6% respirable particles, and 6.5% and 6.0% of SiO2, respectively, determined with the Polezhajev method. They also contained aluminum and iron compounds. Hydroxyproline content in the lungs of the animals following the intratracheal administration of 50 mg of the dusts investigated 3-6 months after the experiment was determined. Determination of Hypro contend within the animals' lungs was pursued with the Stegemann method as modified by Hurych and Chvapil. The biochemical investigation results obtained were statistically analyzed with the t-Student's Test. Single intratracheal administration of dust from the battery roof work stand of the MAKOSZOWY Coking Plant caused within 6 months a statistically significant increase in the lung Hydroxyproline level in experimental animals (t = 13.10). An almost triole Hypro increase with respect to the control group was observed. No analogy between lung Hypro level increase (12.833 mg) and histological change was noted. Such a significant lung Hydroxyproline level increase could have been due to the SiO2 content of dust (6%), as well as to the presence of iron compounds in it (4.98%).(ABSTRACT TRUNCATED AT 250 WORDS)

Air Pollutants↗

Effect of Tamarindus indica fruits on blood pressure and lipid-profile in human model: an in vivo approach.

Fruits of Tamarindus indica were evaluated for their effects on lipid profile, systolic and diastolic blood pressure and body weight in human subjects. Dried and pulverized pulp of T. indica fruits, at a dose of 15 mg/kg body weight, was found to reduce total cholesterol level (p = 0.031) and LDL-cholesterol level (p = 0.004) to a significant extent. Though the fruits exerted no conspicuous effect on body weight and systolic blood pressure, it significantly reduced the diastolic pressure as confirmed by independent sample t-test at 5% significance level.

Administration, Oral↗

Purine bases and atheromatous plaque.

In this work we determined hypoxanthine (HX), xanthine (X), uric acid (UA), allantoin (ALL) and free radicals in atheromatous plaques to improve the comprehension of oxidative stress, a phenomenon which characterizes the evolution of atherosclerotic lesions. Carotid artery plaque were obtained from subjects undergoing endoarterectomy. Pulverized plaque, extracted by water, was used for analysis of oxidative stress factors (allantoin, uric acid, xanthine, hypoxanthine, free radicals). The peroxidation UA-->ALL was very high in the plaque, as was the level of free radicals. The results show that oxidative degradation of nucleotides, such as LDL oxidation, plays a specific role not only in the progression of atherosclerotic lesions but also in the advanced plaque.

Allantoin↗

Proficiency testing as a tool to assess the performance of visual TLC quantitation estimates.

The use of rapid and inexpensive nonlaboratory-based screening tests for drug quality assessments is recommended as a component of a drug quality assurance program in poor resource settings. We have established routine Minilab test procedures to screen product quality and a proficiency testing program to determine the competency of the inspectors and reliability of results. Samples for the proficiency testing were prepared by pulverizing a standard reference tablet of the appropriate drug and making serial dilutions with starch to obtain concentrations of 0, 40, and 100%. The samples, which were labeled only with the drug name and an identifying letter, were given to inspectors for quality screening using Minilab procedures. In round 1 of the proficiency test, only 3 of 28 substandard samples were correctly identified. Round 2 of the proficiency test, which was administered after a performance qualification test for the analytical method, showed much improvement: 19 of 27 substandard drugs were correctly identified, while 5 out of 9 inspectors made the correct inference on the quality of 45 samples. However, in both rounds, 2 inspectors failed to identify substandard samples, indicating that their technical competencies need to be improved for the reliability of the results. Although the thin-layer chromatography screening methods provide a rapid means for drug quality assessment, they need to be put in the hands of competent users. The inclusion of a proficiency test in the screening program provides a measure of determining competency of the personnel and reliability of the results.

Chromatography, Thin Layer↗

Chromosome structure and condensation in relation to DNA integrity.

Single strand DNA breaks were photo-induced in Chinese hamster chromosomes. An electron microscope analysis indicated dispersion or loss of chromatin, and the linear continuity of the metaphase chromosome was mainly represented by longitudinal chromatin fibres. The degree of chromosome damage was related directly to the photo-exposure, and inversely to the condensation level reached by the chromosome prior to exposure. Photo-irradiation of G2 or early prophase chromatin induced chromosome pulverization. However, if the chromatin had reached the maximum metaphase condensation then DNA breakdown only partially disorganized the chromosome general morphology, suggesting that DNA integrity is a factor in chromosome condensation and structural stability at mitosis.

Animals↗

[The roots of Cha and Gambir].

This article attempts to trace the origin of tea. The author believes the ancient Chinese tea, "chia", is either Jicha (water extract from the pith of Acacia catechu that grows naturally in the mountainous border between the Yunnan province of China and southern Asian countries) or Jicha-Kagikazura (water extract from the young branches and leaves of Uncaris gambir, originally found in India/Sri Lanka). Both were pulverized after being kiln-dried and then mixed with water to produce a thick suspension, or tea. Although the drink is bitter and has an astringent property, it has a particular flavor with a refreshing after-taste. Its components with medicinal properties include tannin, catechin, and various flavonoids, making us believe it was worthwhile for the people at the time to consume the drink regularly. Generally speaking, tea cultivation in China flourished south of the Yangzi Jiang River including the present Zhejiang and Anhui provinces. Depending on the regions, there were words for tea in various languages, including the names of places where particular teas were grown. In addition to the names that appear in the famous Chajing book, it is interesting to note Da Fang pronounced tea as "TAH". Because the area south of the Yangzi Jiang has traditionally been active in foreign trade since the ancient and middle ages. People in this region consumed various foreign originated teas as well. This included Gambir, which was introduced to southern Asia (including present Malaysia and Indonesia) and was consumed as an herbal tea under names such as Guo Luo or Ju Luo teas. Paan, from India, also uses Gambir paste and was a popular chewing refreshment to prevent diseases caused by miasma as well as to keep one's mouth clean. The name A-sen-yaku used in Japan was taken from the plant name Acasia, and Gambir was used to dye Buddhist monks' Ke-Ra bags to a blackish yellow color. The Daikanwa dictionary states the Ra in the name, which means thin silk, was later replaced with "A". The official name for Ji-cha [Er Cha] in modern China is "Gaiji-cha", [Hal-Er Cha], which comes from the name of a variety of tea made by the Ai-Ni tribal subgroup of the ethnic Ha-Ni in Yunnan province. The [see character in text] character is pronounced "ni", which is a homophony of [character in text]. Based on these facts, "Ai-Ni" should be considered the same as "Hai-Ni". Because the ethnic groups in Yunnan province used primitive and tough tea leaves, which were eaten instead of being infused in water, the leaves were first fermented by being buried in the ground. Even today, people of these ethnic groups prefer fungus-fermented black tea with a particular flavor. In contrast, the ethnic Hans used and still use improved and softer young shoots of tea leaves to prepare mainly green tea. It has recently been discovered that Acapsia, as well as Gambir, has anti-oxidant properties, and that consumption over time is effective against many lifestyle-related adult diseases. It may be well worthwhile to cast fresh light upon ancient tea drinking customs.

Antioxidants↗

[Clinical application of Modulith SL20 on extracorporeal shock wave lithotripsy for upper urinary tract calculi].

Thirty-nine patients, 27 males and 12 females with renal and ureteral stones, were treated using the Modulith SL 20 between October 1990 and January 1991. Thirty-three of the 39 cases had a single session of extracorporeal shockwave lithotripsy (ESWL) and the other six cases had two sessions. The pulverization rate of ESWL by this device was 84.6%. According to the X-rays taken 21 days after ESWL, of the 37 cases, 14 (37.8%) were stone-free, 18 (48.7%) had residual sandy stones less than 4 mm in diameter, five (13.5%) had residual stone fragments larger than 4.1 mm in diameter, and two cases were not clear. Using the criterion of cases which can be expected to have spontaneous passage, in other words, residual stones less than 4 mm in diameter, lithotripsy with the Modulith SL 20 was regarded as "effective" in 32 of the 37 cases (86.5%). As side effects of this treatment, hematuria was observed for several days after ESWL in all patients, but not other serious complications were observed. Among the 37 cases in which the grade could be evaluated the evaluation for 24 (64.9%) was "useful" and that for 13 (35.1%) "useful to some extent". Therefore, ESWL was performed very successfully.

Adult↗

[Solubility of enamel and synthetic hydroxylapatite on irradiation].

The effect of Co 60-irradiation (70 Gy) on pulverized human enamel and synthetic hydroxyapatite was studied in vitro. Irradiated and non-irradiated samples were experimentally demineralized (pH 5.1) during a period of 28 days. In terms of solubility, defined as the equilibrium of saturation, there was no statistically significant difference between irradiated and non-irradiated enamel. However, in terms of solubility rates, defined as the amount of dissolved substance during the demineralization period, irradiated enamel showed a statistically significantly higher solubility rate than non-irradiated enamel. There was no effect of Co 60-irradiation on synthetic hydroxyapatite.

Dental Enamel Solubility↗

New disinfectants.

The authors estimated the microbicidal effect of disinfectants produced by the firm Henkel Austria, namely Spitaderm, Incidin M spray, Incidur, Incidur spray, Sekusept pulver, Sekusept forte and Maranon H. The aim of the study was the verification of the effectivity of preparations and the proposal of their application in Czechoslovak practice. The estimation was performed in two stages: in vitro and in practice. The standard suspensive method, the suspensive micromethod and the method of carriers were chosen for the experiments, as well as the strains of grampositive and gramnegative bacteria, the spores of B. subtilis, yeasts and the model virus. In the second part of experiments, the disinfectants were applied according to the producer's instructions in inpatient departments of internal medicine and of surgery at the University Hospital in Olomouc in the course of 4 weeks. During the experiment, the rubdowns were taken twice a week from the working places, floor, instruments and hands and the bacterial contamination of the establishment was estimated. In hemodialysing centre, the apparatuses of the artificial kidney were estimated as well, as the preparation Maranon H is recommended for their disinfection. The results of the experiments show that the recommended concentrations of disinfectants and their effective exposition are chosen with sufficient safety coefficient. In chosen wards, the minimum bacterial contamination was observed. All disinfectants were accepted favourably, their scent estimated as pleasant, the staffs evaluated their high cleaning properties and the dosage equipment, ensuring the precise concentration of preparations. With regard to the above mentioned results, the authors recommend to start the licensed production, as all the tested preparations correspond to the exigent demands of modern and effective disinfection.

Bacteria↗

Importance of bile acid structure in amelioration of griseofulvin-induced murine protoporphyric hepatopathy.

This study investigated the effects of bile acid structure on griseofulvin-induced murine hepatopathy and explored the mechanism(s) of cholestasis in this model of protoporphyria. Mice were fed pulverized chow with cholate, chenodeoxycholate, or ursodeoxycholate, with or without griseofulvin. After 1 to 4 weeks, bile flow, bile acid excretion and composition, biliary protoporphyrin excretion, hepatic protoporphyrin contents, liver histology, and griseofulvin plasma concentrations were determined. Additionally, bile acid absorption was measured. Griseofulvin induced a progressive increase in liver weight, hepatic protoporphyrin content, and histopathologic evidence of cholestasis. Biliary protoporphyrin excretion increased and pigmented gallbladder microliths developed. Bile flow and bile acid excretion fell in relation to liver weight but not in relation to body weight. Cholic acid augmented biliary protoporphyrin excretion, markedly reduced hepatic protoporphyrin content, and obviated the development of intrahepatic biliary thrombi. Ursodeoxycholate and chenodeoxycholate both reduced biliary protoporphyrin excretion. This was associated with bile acid compositional changes, particularly a fall in cholic acid. Although histopathologic abnormalities were not altered, these bile acids reduced hepatic protoporphyrin contents. Bile acid treatments with griseofulvin all increased bile flow and bile acid excretion relative to controls, but differences in the relationship of bile flow to bile acid structure on protoporphyrin disposition. They document biliary excretion as the principal mode of cholic acid amelioration of griseofulvin-induced hepatopathy. They also suggest distinctive roles for griseofulvin and protoporphyrin in the generation of the cholestasis.

Absorption↗