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PubMed2000

Postoperative confusion preceded by decreased frontal lobe haemoglobin oxygen saturation.

We describe a 58-year-old male patient with confusion and prolonged recovery after liver transplantation. A cause was not apparent for the confusion, but during surgery, monitoring of the frontal lobe cerebral haemoglobin oxygen saturation by near-infrared spectrophotometry showed cerebral hypo-oxygenation despite optimization of conventional cardiovascular parameters. It is possible that intraoperative cerebral ischaemia is the cause of postsurgical confusion and with near-infrared spectrophotometry this hypothesis may be tested clinically.

Anesthesia Recovery Period↗
PubMed2000

[Evaluation of cariogenic potential of Streptococcus mutans isolated from caries-free and -active persons: abilities to synthesize water-soluble and -insoluble glucans].

OBJECTIVE: In this study, authors investigated abilities of Streptococcus mutans (serotype c) strains to synthesize water-soluble and water-insoluble glucans. METHODS: Streptococcus mutans strains were isolated from people with different carious experiences, which were divided into two groups: caries-free (DMFS = 0) group including 19 persons and caries-active group(DMFS > or = 6) including 40 persons. Totally 105 genotypes of Streptococcus mutans strains were obtained, including 22 strains from the caries-free group and 83 strains from the caries-active group. The differences of abilities to synthesize water-soluble and water-insoluble glucans between these two groups were compared in order to find the correlationship between the synthesis of glucans and caries experience. Then, Streptococcus mutans were cultured in TPY liquid medium containing 1% sucrose in an anaerobic incubator at 37 degrees C for 24 hours. Glucans synthesized by Streptococcus mutans was qualified by using infrared spectrophotometry. The amounts of water-soluble and water-insoluble glucans were measured by using the anthron method. RESULTS: According to the same absorption tops position analysed by infrared spectrophotometry, glucans samples were certified. The amounts of glucans synthesized by Streptococcus mutans strains were different between strains of different genotypes even isolated from the same person. Mostly, the amount of water-insoluble glucans was higher than that of water-soluble glucans between different genotype Streptococcus mutans strains. The oral environments of patients in the caries-active group harbored more Streptococcus mutans strains with higher water-soluble glucans producing ability than those of the caries-free group did (P < 0.05), and patients of the caries-active group also harbored more Streptococcus mutans strains with higher water-insoluble glucans producing ability than those of the caries-free group did(P < 0.01). CONCLUSION: 1. Glucosyltranferases of different genotype strains are different in glucans production, and different genotype strains relate to different cariogenic abilities. 2. Glucans was one of cariogenic factors, and water-insoluble glucans was more important than water-soluble glucans in cariogenic ability of Streptococcus mutans. 3. The differences in glucans production of isolated strains might relate to differences in carious experiences.

Dental Caries↗
PubMed2006

[Regional cerebral oxygen saturation in neonates with meconium aspiration syndrome].

OBJECTIVE: This study examined the changes of regional cerebral oxygen saturation (rSO2) by noninvasive near infrared spectrophotometry in neonates with meconium aspiration syndrome (MAS). METHODS: Seventy-three full neonates with MAS were divided into three groups by respiratory symptoms: asymptomatic group (group 1, n=38), common group (group 2, n=28) and severe group (group 3, n=7). Near infrared spectrophotometry was used to measure the cerebral rSO2 on days 1, 3, 5 and 7 after birth. Thirty healthy full-term newborns served as the Control group. RESULTS: The cerebral rSO2 of group 1 decreased significantly compared with that of the Control group between days 1 and 3 (P < 0.05). The cerebral rSO2 of group 2 or group 3 was significantly lower than that of group 1 and the Control group on days 1, 3 and 5 (P < 0.05). The MAS patients with mild hypoxic-ischemic encephalopathy (HIE) had significantly higher brain rSO2 levels than those with medium or severe HIE on days 2, 3 and 5 (P < 0.05). CONCLUSIONS: The cerebral rSO2 decreased in neonates with MAS. The values for rSO2 correlated with the severity of HIE in MAS patients.

Brain↗
PubMed2004

[Urinary stones in Tunisian infants, based on a series of 64 cases].

OBJECTIVE: To define the epidemiological and clinical characteristics of urinary stones in infants, to study the role of stone chemical analysis in the aetiological assessment of urinary stones and to define the various treatment modalities adapted to this age-group. PATIENTS AND METHODS: Between 1984 and 2002, 64 infants (age: 5-24 months) were hospitalised for urinary stones. Urine culture was performed in all patients and metabolic assessment was performed in 24 patients. Physicochemical stone analysis was performed by infrared spectrophotometry in 37 patients. RESULTS: Upper tract and lower tract stones were equally prevalent. Urine culture was positive in 48 cases. The micro-organism most frequently isolated was Proteus mirabilis (19 cases). The metabolic assessment was normal in 15 patients and pathological in 9 patients. Infrared spectrophotometry showed that 17 stones were pure. 60 patients were treated surgically, 2 were treated by endoscopy associated with intracorporeal lithotripsy. One patient was treated medically and another patient passed the stone spontaneously while in hospital. No intraoperative or postoperative complication was observed. No recurrence was observed in this series. The mean follow-up is 16 months (range: 6 months to 94 months). CONCLUSION: The epidemiological profile of urinary stones in infants in Tunisia is situated between that observed in developed countries and that observed in developing countries. In our study, the incidence of metabolic abnormalities appears to be low despite a high rate of consanguinity in Tunisia. This can be largely explained by the absence of an aetiological survey and/or an inadequate survey when it is performed.

Child, Preschool↗
PubMed2002

Comparison by X-ray diffraction and infrared spectroscopy of two samples of alpha quartz with the NIST SRM 1878a alpha quartz.

The aim of this study was to compare the X-ray diffraction and infrared spectrophotometric patterns of two samples of alpha quartz (QUIN1 and QUIN2) with that of NIST SRM 1878a alpha quartz certified 100% crystalline. As it is known that the intensity diffracted and the absorbance per mass unit for a given type of alpha quartz depend on its particle size, this factor was taken into account. To do this, different types of alpha quartz were sampled on filters using a Dorr-Oliver cyclone to select particle size. Variation in the flow rate of the cyclone in the range 1.2-2.8 l/min allowed the volume median diameter of the sampled particles to be varied. For the four strongest diffraction lines it was observed that the intensity per mass unit increased with the volume median diameter of the particles. For infrared spectrophotometry for analytical band wavelengths close to 12.5 micro m, it was observed that the absorbance per mass unit decreased as particle size increased. The opposite effect was noted for analytical band wavelengths >14.4 micro m. Compared with SRM 1878a alpha quartz, certified 100% crystalline, the purity of QUIN1 alpha quartz was 93.1% (confidence interval 92.4-93.8%) when measured by X-ray diffraction and 91.5% (confidence interval 90.1-92.9%) when measured by infrared spectrophotometry. In the case of QUIN2 alpha quartz the purity was globally lower.

Calibration↗
PubMed1999

Preparation and dissolution property of ipriflavone solid dispersion.

AIM: To prepare and identify ipriflavone (IP) solid dispersion, and determine its dissolution property. METHODS: The solvent method was used for preparation and differential scanning calorimetry (DSC), X-ray diffraction and infrared spectrophotometry for identification of IP solid dispersion. The dissolution of the dispersion was determined with paddle method. RESULTS: The dissolution of IP solid dispersion consisting of IP and povidone-k30 (PVP) (1:8) in artificial gastric juice is 6.15 times as high as that of IP alone. The DSC curves, X-ray diffraction patterns and infrared spectrophotometries of IP have been changed obviously by the dispersion. CONCLUSION: The dissolution of IP is increased by solid dispersion method.

Isoflavones↗
PubMed2000

A new prostatic stent for the treatment of benign prostatic hyperplasia in high-risk patients.

OBJECTIVES: The objective of this study was to evaluate the efficacy and safety of a new prostatic stent (Trestle((R)), Boston Scientific Microvasive) for the treatment of BPH in patients with complete urinary retention and considered to be inoperable. METHODS: The efficacy of the stent was evaluated in terms of return of micturition, level of patient satisfaction, uroflowmetry and residual urine. Any stents removed were examined by infrared spectrophotometry for the presence of crystalline encrustations. RESULTS: From December 1997 to April 1999, 20 stents were inserted under local anaesthesia in 17 patients aged 54-90 years. Stents remained in place for an average of 3.5 months. Two migrations were reported. The mean maximum flow rate was 13.7 ml/s and the mean residual urine was 110 ml. The infrared spectrophotometry study revealed a glycoprotein film on stents in place for 1-6 months, accompanied by uric acid crystals on stents in place for 9 months. CONCLUSION: The Trestle prostatic stent is effective and constitutes a good alternative to surgical treatment in patients with a high operative risk.

Aged↗
PubMed2006

[Identification of lithogenic risk factors by a simplified first-line laboratory assessment in urinary calculi patients].

INTRODUCTION: A simplified first-line laboratory assessment is recommended by the Stones Committee of the Association Française d'Urologie (CLAFU) right from the first episode of renal stones to detect any lithogenic risk factors. This study was designed to evaluate the feasibility of this assessment in urology, to specify the frequency of risk factors and to compare the results between first stone formers and recurrent stone formers. MATERIAL AND METHODS: This prospective study included patients with a first stone or recurrent stones with no previous laboratory assessment. Known cases of secondary stones were excluded. The stone or fragments had to be analysed by infrared spectrophotometry. In addition to the usual assessment, the first-line laboratory assessment was performed two to three months after the acute episode with a blood test (calcium, phosphorus, uric acid and creatinine), 24-hour urine collection (volume, calcium, uric acid, urea, creatinine, sodium) and first morning urine sample (pH, density, crystals). RESULTS: The results are based on 115 of the 204 patients included (69 first stones, 46 recurrent stones). The assessment was performed and interpreted easily, except for collection of stone fragments. Infrared spectrophotometry was performed in only 49 patients. Whewellite was the most frequent crystalline structure. No patients presented hyperparathyroidism or renal failure. In 69% of cases, the urinary assessment identified one or several risk factors, with insufficient diuresis (42%), hypercalciuria (29%), hypernatriuria (41%), high urinary urea (29%), and hyperuricuria (20%). 25% of patients had a single abnormality, 20% had two abnormalities, the most frequent combination being hypercalciuria-hypernatriuria, and 11% had 4 or more abnormalities. Comparison of first stone formers and recurrent stone formers did not reveal any difference in the frequency of lithogenic risk factors. CONCLUSION: This easy to perform assessment identified lithogenic risk factors in many cases, in both first stone formers and recurrent stone formers, that can guide the prevention of recurrent stones.

Feasibility Studies↗
PubMed1995

Rapid computer-assisted infrared analysis of urinary calculi using photoacoustic detection.

The application of commercial spectrum-analysing software to quantitative analysis of urinary stones by Fourier transform infrared spectrophotometry is described. The infrared technique is straightforward in comparison with other stone analysis procedures of similar scope and affords significant time savings. The use of partial least squares regression in the analysis program enables better quantitation of stone components than has been hitherto possible using infrared methods. All the principal and many less common stone constituents can be detected and measured. Photoacoustic detection was employed, thus enabling non-destructive analysis with minimal sample preparation. A comparison is made between the infrared procedure and the hybrid thermogravimetric plus "wet" chemistry technique, which it has superseded for routine urinary stone analysis in the author's department.

Acoustics↗
PubMed1975

Thiopental suicide -- case report.

Thiopental was indicated in the suicide death of a hospital employee. The blood thiopental level was determined to be 27.9 mg% by ultraviolet spectrophotometry, and positive identification was accomplished using gas chromatography, thin-layer chromatography, and infrared spectrophotometry.

Adult↗
PubMed1979

Field evaluation of selected monitoring methods for phosgene in air.

Four selected methods have been evaluated and field tested as candidates for a specific, continuous procedure for monitoring phosgene in air at or below concentrations of 0.05 ppm. The methods evaluated were automated colorimetry, gas chromatography, infrared spectrophotometry and a recently developed paper tape monitor. A standard manual colorimetric procedure was used as a reference method. The paper tape, infrared and automated gas chromatographic techniques most closely fulfilled the criteria set forth for an "ideal", selective, continuous procedure for phosgene.

Air Pollutants↗
PubMed1976

The effect of grinding of human dentine examined by X-ray diffraction, infrared spectroscopy, and electron microscopy.

Analysis of human dentine by infrared spectrophotometry suggests that ball-grinding may result in damage of the apatite crystallites. The present study includes further assessments of this effect by X-ray diffraction, infrared spectroscopy, and electron microscopy. Each of three coarse-ground dentine samples (Group I) was divided into three portions of 30 mg. One of these portions was ball-ground for approximately 1 min (Group II), the second portion for 6 min (Group III), and the third portion for 23 min (Group IV). The 002 reflection showed line broadening, most marked from Group II to III. Electron microscopy showed a gradual change in crystallite appearance with increased grinding, most pronounced from Group II to III. These observations indicate that by prolonged grinding a limit is approached where no further changes in the crystallites occur. Electron microscopy also indicated that fracture of the crystallites might have occurred. This was probably accompanied by strains in the lattice. The infrared spectra indicated that no breakdown of the apatite structure had occurred during the entire grinding.

Apatites↗
PubMed1984

Isolation and identification of 1 alpha,25-dihydroxy-24-oxovitamin D3, 1 alpha,25-dihydroxyvitamin D3 26,23-lactone, and 1 alpha,24(S),25-trihydroxyvitamin D3: in vivo metabolites of 1 alpha,25-dihydroxyvitamin D3.

Three new in vivo metabolites of 1 alpha,25-dihydroxyvitamin D3 were isolated from the serum of dogs given large doses (two doses of 1.5 mg/dog) of 1 alpha,25-dihydroxyvitamin D3. The metabolites were isolated and purified by methanol-chloroform extraction and a series of chromatographic procedures. By cochromatography on a high-performance liquid chromatograph, ultraviolet absorption spectrophotometry, mass spectrometry, Fourier-transform infrared spectrophotometry, and specific chemical reactions, the metabolites were identified as 1 alpha,25-dihydroxy-24- oxovitamin D3, 1 alpha,25-dihydroxyvitamin D3 26,23-lactone, and 1 alpha,24(S),25-trihydroxyvitamin D3. According to these procedures, the total amounts of the isolated metabolites were as follows: 1 alpha,25-dihydroxyvitamin D3, 23.6 micrograms; 1 alpha,25-dihydroxy-24- oxovitamin D3, 1.8 micrograms; 1 alpha,25-dihydroxyvitamin D3 26,23-lactone, 9.2 micrograms; 1 alpha,24(R),25-trihydroxyvitamin D3, 15.4 micrograms; 1 alpha,24(S),25-trihydroxyvitamin D3, 1.0 microgram. With recovery corrections, the serum levels of each metabolite were approximately 49 ng/mL for 1 alpha,25-dihydroxyvitamin D3, 3.7 ng/mL for 1 alpha,25-dihydroxy-24- oxovitamin D3, 19 ng/mL for 1 alpha,25-dihydroxyvitamin D3 26,23-lactone, 32 ng/mL for 1 alpha,24(R),25-trihydroxyvitamin D3, and 2.1 ng/mL for 1 alpha,24(S),25-trihydroxyvitamin D3.

Animals↗
PubMed1986

Metabolism of 25-hydroxycholecalciferol in human promyelocytic leukemia cells (HL-60). Isolation and identification of (5Z)- and (5E)-19-nor-10-oxo-25-hydroxycholecalciferol.

Human promyelocytic leukemia cells incubated with 25-hydroxy[26,27-methyl-3H] cholecalciferol (1 microCi) or non-radioactive 25-hydroxycholecalciferol (550 micrograms) produced significant quantities of two vitamin D3 metabolites. The two metabolites were isolated and purified by methanol chloroform extraction and a series of chromatographic procedures. The metabolite purification and elution positions on these columns were followed by radioactivity and their ultraviolet absorption at 310 nm. The two metabolites have been unequivocally identified as (5Z)- and (5E)-19-nor-10-oxo-25-hydroxycholecalciferol by ultraviolet absorption spectrophotometry, mass spectrometry, Fourier-transform infrared spectrophotometry and co-chromatography with synthetic compounds on a high-performance liquid chromatograph. (5E)- but not (5Z)-19-nor-10-oxo-25-hydroxycholecalciferol was able to induce HL-60 cell phenotypic and functional differentiation. However, these two metabolites of 25-hydroxycholecalciferol did not bind specifically to the chick intestinal 3.7 S. receptor protein for 1 alpha,25-dihydroxycholecalciferol. The precise biological role of these metabolites is as yet unclear.

Animals↗
PubMed1988

Measurement of 2H2O by IR absorbance in doubly labeled H2O studies of energy expenditure.

The energy expenditure of animals in their natural surroundings can be determined by measuring the turnover in body water of isotopes of oxygen and hydrogen. We evaluated the use of infrared spectrophotometry for measuring 2H2O in small (20-microliters) water samples also labeled with 18O. For 2H2O over the enrichment range of 0.1-1 atom%, there was a linear relationship between infrared absorbance and 2H2O enrichment. 2H2O enrichments could be measured with a precision and accuracy of less than or equal to 1%, using this relationship. The presence of 18O in water samples in enrichments of up to 1 atom% had no significant effect on measurement of 2H2O by infrared absorbance. We measured the simultaneous turnover rates of 2H2O and 3H in mice and turtles also labeled with 18O. Our results validated the use of infrared absorbance in doubly labeled water measures of energy expenditure and indicated that the fractionation factors in vivo for 2H2O and 3H do not differ.

Algorithms↗
PubMed1987

Metabolism of the vitamin D3 derivative (24R)-hydroxycalcidiol by human promyelocytic leukemia cells (HL-60). Isolation and identification of (5Z) and (5E)-(24R)-19-nor-10-oxo-24-hydroxycalcidiol.

Human promyelocytic leukemia cells (HL-60 cells) incubated with (24R)-hydroxy[26,27-methyl-3H]calcidiol (0.2 microCi) or non-radioactive (24R)-hydroxycalcidiol (370 micrograms) produced significant quantities of two new vitamin D3 (calciol) metabolites. The metabolites were isolated from HL-60 cell culture media by methanol/chloroform extraction and a series of chromatographic procedures. The two new metabolites were identified as (5Z)- and (5E)-(24R)-19-nor-10-oxo-24-hydroxycalcidiol by HPLC analysis, ultraviolet absorption spectrophotometry, mass spectrometry and Fourier-transform infrared spectrophotometry. According to the isolation and purification procedures, the total amounts of 3.04 micrograms (5Z)-(24R)-19-nor-10-oxo-24-hydroxycalcidiol (lambda max = 310 nm, epsilon = 17070 M-1 cm-1) and 8.89 micrograms (5E)-(24R)-19-nor-10-oxo-24-hydroxycalcidiol (lambda max = 312 nm, e = 24,500 M-1 cm-1) were calculated, assuming an Mr of 418. The activity of 19-nor-10-oxo-(24R)-hydroxycalcidiol to promote HL-60 cell differentiation was higher than the activity of the precursor (24R)-hydroxycalcidiol suggesting a possible biological action of this metabolite in HL-60 cells.

24,25-Dihydroxyvitamin D 3↗