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PubMed1989

The relation between urinary tract infections and stone composition in renal stone formers.

During a seven-year period (1975-1981) a total of 1325 patients hospitalized for stone disease were studied as to the occurrence of positive urine cultures. Urinary stones from 535 surgically treated patients were analyzed with infrared spectrophotometry and the relationships between stone composition, level of surgery and bacteriological strains were studied. Positive urinary cultures were found in 34% of the surgically treated patients and in 21% of those not operated upon. Among the surgically treated patients with urinary tract infection (UTI) E. coli was the most frequent microorganism (35%), followed by Proteus (28%). Patients with Proteus infection had the highest frequency of UTI episodes, most of which occurred before hospitalization. There was a higher frequency of magnesium ammonium phosphate (MAP) calculi among patients with Proteus infection than among those with non-Proteus infection, in whom no difference in stone composition was found. Patients infected with E. coli had more phosphate-containing stones (CaP+MAP) than non-infected patients. The highest frequency of oxalate calculi (CaOx+CaOx/CaP) was found among patients without infection. No E. coli infections were seen in male patients with CaP and MAP calculi. MAP stones were most often found in the kidney and oxalate stones in the ureter.

Calcium Oxalate↗

PubMed1986

Characterization and composition of uroliths from domestic fowl.

Urolithiasis (kidney stone formation) is an acquired degenerative kidney lesion affecting sexually mature and immature domestic fowl. For the present study, uroliths were collected from three commercial flocks during outbreaks of urolithiasis. Uroliths also were collected from a research flock in which urolithiasis was induced by feeding immature chickens a diet formulated to contain excess calcium (3.25% Ca) and .4% available phosphorus. All uroliths were tested by x-ray diffractometry, infrared spectrophotometry, and emission spectrography. With one exception, the stones were composed of compact masses of microcrystalline to fine pleomorphic crystals of calcium sodium urate, with random substitution of magnesium for calcium, and potassium for sodium. No initiating nidus was evident. One of four stones from one laying hen flock was positively identified as an ammonium acid (hydrogen) urate. The unique calcium-sodium-urate stone composition in all but one of the stones tested suggests that similar processes were involved in stone formation in the four different flocks.

Animals↗

PubMed2000

[Silicate calculi: report of two cases].

Two patients, aged 53 and 55, discharged stones spontaneously. Infrared spectrophotometry of the stones demonstrated silicate. They had no history of taking magnesium silicate. Thirty cases of silicate calculi previously reported in the Japanese literature are reviewed.

Aged↗

PubMed1975

The analysis of pharmaceuticals by combined gas chromatography-mass spectrometry. I. The analysis of a medicated aerosol spray.

A medicated aerosol product was qualitatively analyzed by combined gas chromatography-mass spectrometry. The data were processed by a minicomputer. Ten of the 11 peaks in the gas chromatogram were identified with the assistance of the National Institutes of Health/Division of Computer Research and Technology/Chemical Information System mass spectral search system. The unidentified peak is probably a member of the terpene class. The aerosol propellants were also partially analyzed by infrared spectrophotometry.

Aerosol Propellants↗

PubMedDate not supplied

[Factitious lithiasis: Case report from Western Algeria].

A 19-year-old woman with recurrent lithiasis was admitted to the urology department for renal colic. Although radiologic examinations and laboratory tests were negative, the patient regularly brought into consultations small "stones", resembling gravel, that she said had been spontaneously expelled. These 42 samples were the object of a preliminary morphological analysis under a binocular magnifier to detect their particulate components. A non-metabolic origin was suspected from the organoleptic characteristics of their surfaces and sections. In view of the diversity of the materials of these apparently false calculi, methods of precise physical analysis were necessary to ascertain their exact origin and thereby confirm the diagnosis of factitious lithiasis. The use of two methods of physical analysis, infrared spectrophotometry and x-ray diffraction, enabled us to determine their exact chemical and mineralogical composition. The samples claimed to be of urinary origin actually consisted of exogenous products of various compositions. Some samples were made of pure calcite, others of mixed calcite and silicates. Moreover several samples of the patient's first morning urine showed no correlation between the nature of the crystalluria and the composition of these stones. These tests made it possible to direct the clinician towards useful complementary investigations. This strange case represents 0.1% of the urinary calculi analysed in Western Algeria.

Adult↗

PubMedDate not supplied

[The characteristics of the chemical composition and structure of urinary stones and their prevalence in the cities of Moscow, Berlin and of the Kirghiz SSR].

The authors studied the features of urolithiasis in three different geographical regions: Moscow, the Kirghiz SSR, and Berlin from the findings of examination of the composition and structure of uroliths removed by operation or passed spontaneously, (602 concrements from Moscow, 10,000 from Berlin, and 127 from Kirghizia). X-ray diffraction measurement, infrared spectrophotometry, and polarizing microscopy were conducted to analyze the composition and structure of the stones. Complex biochemical examination was carried out in patients from Moscow and Kirghizia. According to the results of the study, the following features of urolithiasis are common in the studied regions: (1) prevalence of oxalate lithiasis on the whole, which points to the principal role of metabolic factors in lithogenesis; (2) approximately similar amounts of apatite carbonate crystals in the uroliths; (3) certain similarity in composition of concrements from Berlin and Kirghizia. The most essential differences are: (1) the frequency of renal oxalate stones is highest in Berlin and lowest in Moscow. The prevalent types of calcium oxalate stones are: whewellite of concentric structure (linked with hyperuricemia) in Kirghizia; whewellite of small randomly orientated crystals (linked with hypercalciuria) and stones with signs of transformation of weddellite to whewellite in Moscow; (2) lesser distribution of phosphate lithiasis in Berlin than in Kirghizia and particularly in Moscow. Prevalence of struvite crystals in stones from Moscow, the formation of which is linked with the vital activity of Proteus and E. coli; (3) higher distribution of urate lithiasis in Moscow and particularly in Kirghizia where significant metabolic risk factors of lithogenesis were revealed.

Berlin↗

PubMed1990

[A case of silicate urolithiasis].

We report a case of silicate calculi with no history of taking magnesium trisilicate. A 33-year-old woman was sent to our hospital as an emergency case because of severe right lower flank pain. Physical examination was unremarkable except for severe right cost-vertebral angle knock pain. She denied administration of a magnesium trisilicate anti-acid before. She was admitted to the urologic ward since the pain did not relieve in spite of several analgesics. The stone passed spontaneously on the third hospital day. Analysis by infrared spectrophotometry demonstrated the composition to be over 98% of silicate. A review of the literatures discloses only 21 cases of silicate stones.

Adult↗

PubMed1990

Cerebral tissue oxygen status and psychomotor performance during lower body negative pressure (LBNP).

Cerebral oxygen sufficiency was studied noninvasively, using multiwavelength near-infrared spectrophotometry, in eight subjects exposed to lower body negative pressure (LBNP) of up to -90 mm Hg to induce presyncopal symptoms and signs. LBNP caused only small changes in the forebrain measures until the last 60 s of the exposures, whereupon oxyhemoglobin (HbO2) and oxidised cytochrome c oxidase fell, reduced hemoglobin (Hb) rose slightly, and the tissue blood volume (HbO2 + Hb) fell. In subjects showing presyncope, these changes anticipated the onset of a terminal bradycardia by some 20 s and may provide the trigger for cardiovascular decompensation, while the cessation of LBNP led to an overshoot in cerebral blood volume suggestive of a reactive hyperemia. Psychomotor testing showed a significant slowing of reaction time with LBNP, but only for the easiest component of a complex task, while saccadic latencies were found to be shortened following LBNP exposure.

Adult↗

PubMed1990

[Urinary lithiasis due to triamterene].

Iatrogenic renal stones although rare, must be diagnosed. It is therefore essential to use modern techniques such as infrared spectrophotometry. We report a new case of renal stones due to triamterene. Various predisposing factors are examined, in particular urine acidity and the presence of protein in the stones.

Aged↗

PubMed1990

Synthesis and pharmacological evaluation of acyl derivatives of phenelzine.

Acyl derivatives of phenelzine were required for pharmacological evaluation. Eight mono- and di-acyl derivatives were synthesized and characterized by gas chromatography, mass spectrometry, nuclear magnetic resonance and infrared spectrophotometry. Selective acylation was observed with both acetic anhydride and ethyl chloroformate. In aqueous medium, monoacylation yielded N1-acetyl- and N1-(ethoxy-carbonyl)-phenelzine exclusively, whereas in non-aqueous medium only N2-acetyl and N2-(ethoxycarbonyl) products were obtained. NMR temperature studies were conducted to ascertain the presence of rotational isomers and their ratios. At room temperature, one ethoxy-carbonyl and four phenelzine acetate derivatives were present as mixtures of rotamers. Preliminary evaluations of the MAO-inhibiting properties of acylated phenelzines indicate that a hydrogen atom on the N1-position of phenelzine and its derivatives is essential for activity.

Acylation↗

PubMedDate not supplied

[Determination of the composition of the concretions in patients with nephrolithiasis by metabolic indices].

The authors considered an important problem of in vivo verification of urolith composition as specifying the choice of drug treatment and prevention of urolithiasis. 84 nephrolithiasis patients were allocated to 4 groups according to their concrement compositions (after spontaneous or surgical removal): 23 patients with urate calculus, 19 with oxalate, 20 with phosphate and 22 with oxalate-phosphate concrements. Polarizing microscopy, x-ray structural analysis and infrared spectrophotometry were employed for verification of calculi composition. Biochemical assay was used for the assessment of serum and circadian excretion of calcium, phosphates, sodium, potassium, uric acid, oxalates and uroacidimetric values. The findings were subjected to discriminant computed analysis which resulted in 6 linear computable functions defining 4 selective groups with regard to biochemical blood and urine data. The aforementioned functions were used in diagnostic routine for the in vivo assessment of calculous composition in 26 controls. In 61.5 per cent of the patients the diagnosis was confirmed, in 34.6 per cent it was verified, and only in 3.9 per cent the diagnosis turned to be erroneous.

Diagnosis, Computer-Assisted↗

PubMed1988

A near-infrared spectrophotometric method for studying brain O2 sufficiency in man during +Gz acceleration.

A technique for the noninvasive monitoring of cerebral oxygen status was evaluated on volunteer subjects on the USAF School of Aerospace Medicine centrifuge. By using multiwavelength near-infrared spectrophotometry, the instrumentation measured changes in the quantities of reduced and oxygenated hemoglobin (and their sum, an indicator of cerebral blood volume), and the quantity of oxidized cytochrome c oxidase within the forebrain. Tests used acceleration of up to 9 G with onset rates from 0.1 to 5.0 G.s-1, anti-G suits and straining maneuvers, and hyperoxic and hypoxic breathing mixtures. In general, +Gz acceleration produced a fall in blood volume within the cerebral microcirculation with a relative increase in the content of reduced hemoglobin and a tendency towards reduction of cytochrome c oxidase. These findings are discussed in relation to accepted changes in arterial blood pressure, cerebral blood flow, and arterial oxygen saturation caused by acceleration exposure.

Acceleration↗

PubMed1987

[Identification of a metabolite of floctafenine in urinary calculi].

There are three 4-amino-quinolines used for their analgesic properties: glafenine, antrafenine and floctafenin. Urinary calculi due to glafenine have been described since 1980. Recently two cases of renal calculi containing antrafenic acid have been reported. We discovered a metabolite of floctafenin in a bladder calculus and describe its identification by infrared spectrophotometry and thin-layer chromatography.

Aged↗

PubMed1988

[13 cases of drug-induced calculi].

All urinary stones should undergo detailed studies to identify those related to drug therapy. Among 520 stones analyzed by infrared spectrophotometry, we found 13 drug-induced stones (13/520: 2.5%). Drug-induced stones were caused by glafenine in 7 cases, piridoxylate in 4 cases, triamterene in one case and an unknown organic compound in one case. Glafenine stones appear to develop more readily in infected urine. Triamterene stones are often associated with uric acid disorders. Piridoxylate induces the formation of glyoxylate which is responsible for hyperoxaluria and formation of oxalocalcium stones.

Aged↗

PubMed1988

An infant fatality involving ajmaline.

An infant fatality following accidental ingestion of ajmaline is described. Ajmaline was determined by thin-layer chromatography and infrared spectrophotometry, and quantitated by high performance liquid chromatography. The ajmaline concentration in blood was 5.5 micrograms/mL. The toxicological data relevant to the interpretation of case findings are presented.

Ajmaline↗

PubMedDate not supplied

[Distribution of hydrocarbon residues in the sediment from Bizerte lagoon (Northern Tunisia)].

The study of hydrocarbon residue by infrared spectrophotometry in the deposits of the Bizerta Lagoon allows us to recognize a polluted zone sector of the Menzel Bourguiba Arsenal. The Eastern part of the lagoon, a zone of "oyster parks" is not affected by pollution. Its average contents of hydrocarbon residues are clearly below the maximum content determined by international regulations. The distribution of hydrocarbon residues in the superficial sediments following three well differentiated zones, reflects the weak hydrodynamism in the lagoon. The vertical variations of this pollution agent contents show the preferential accumulation of the terrigenous material, from lake Ichkeul , in the western part and the weak rate of sedimentation in the eastern zone.

Hydrocarbons↗

PubMed1982

The identification of capsaicinoids in tear-gas spray.

"Natural" capsaicin has been identified in "Halt!" sprays by thin-layer chromatography (TLC), high performance liquid chromatography (HPLC), infrared spectrophotometry (IR), and gas chromatography/mass spectrometry (GC/MS). Individual capsaicinoids have been identified as capsaicin, dihydrocapsaicin, and nordihydrocapsaicin. The recommended analytical procedure for small samples is HPLC followed by GC/MS. The alternative procedure of solvent extraction and preparation TLC followed by IR is recommended for large samples.

Capsaicin↗

PubMed1994

[Instrumental analysis of medicinal plants and their drug products].

The experiences obtained during the development of gas chromatographic and other (GC, TLC and infrared spectrophotometric) methods for the 7th edition of the Hungarian Pharmacopoeia for essential oils and drugs containing essential oils are summarized with emphasis on the selection of suitable internal standard for the gas chromatographic assays. The qualitative and quantitative estimation of bitter compounds and polyphenoles e.g. flavonoids and procyanidines by means of ultraviolet and infrared spectrophotometry and HPLC is also described. Some HPLC methods for the determination of anthocyan and carotinoid derivatives are also presented. These are not yet included in the pharmacopoeia but are successfully used for the analytical investigation of commercially available medicinal plants and drug products made thereof.

Chromatography, Gas↗