Determination of cyclohexanone in aqueous solutions stored in PVC bags by isotope dilution gas chromatography-mass spectrometry.
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Cyclohexanones↗
Biomedical subjects
S Jacobsson
Publications and source records attributed to S Jacobsson.
Dental replacement resorption after bone grafting to the alveolar cleft.
In a review of 100 consecutively performed bone grafts to the alveolar cleft, replacement resorption was found in 7 teeth adjacent to the cleft. Damage to the periodontal tissues during surgery is considered to be the main cause of this complication: granulation tissue from the bone graft may have some influence. Treatment of the affected teeth eventually includes extraction or surgical removal. To minimize the risk for this complication, we suggest that bone grafting should be done when the canine (or lateral incisor) is in an early stage of eruption and that orthodontic uprighting of the medial incisor should be done after surgery.
Adolescent↗
Determination of noscapine and its metabolites in plasma by coupled-column liquid chromatography.
Noscapine, narcotoline and cotarnine were quantified in deproteinized plasma samples by using a coupled-column liquid chromatographic system. The drug and the metabolites were first separated into two groups on a short polar precolumn (-CN) with an acidic mobile phase, containing a low content of acetonitrile. The metabolites were transferred to a hydrophobic analytical column (C18) and separated with a mobile phase containing a counter ion and a co-ion in an acidic buffer with an high acetonitrile content. Noscapine was transferred to another hydrophobic analytical column (C18) with a mobile phase containing a counter ion in an acidic buffer with an high acetonitrile content. Ultraviolet detection at 310 nm was used for all three compounds. The limits of quantitation were 9 ng/ml for noscapine, 13 ng/ml for cotarnine and 20 ng/ml for narcotoline. The within-day precisions were better than 6% (relative standard deviation), and the absolute recoveries were above 82%.
Alkaloids↗
Maxillary development in six unilateral cleft lip and palate children treated with passive orthopaedic plates.
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Alveolar Process↗
On rhinomanometry in rhinoplasty.
Changes in nasal obstruction, nasal airway resistance, and postoperative nose appearance were evaluated in 92 rhinoplasty patients. Fifty-six patients had a deviation of their nose from the midline preoperatively. They were improved according to rhinomanometry whether the rhinoplasty was combined with a functional septoplasty or with a submucous resection. Among the other 36 patients who did not have a deviation of the nose from the midline, 23 had a rhinoplasty combined with a functional septoplasty and 13 had no surgery on the septum at all. Rhinomanometrically, only patients operated on with the combined operation were improved; the rest became worse, even in terms of nasal obstruction. Among 58 patients from both groups with preoperative nasal obstruction, there was agreement for 76 percent between the subjective and rhinomanometric changes. The advantages of giving the rhinomanometric results in a polar coordinate system are discussed.
Adolescent↗
Contact allergy to dehydroabietic acid derivatives isolated from Portuguese colophony.
7-oxodehydroabietic acid and 15-hydroxydehydroabietic acid were isolated as their methyl esters from Portuguese colophony of the gum rosin type and identified as contact allergens. Another oxidation product of dehydroabietic acid, 15-hydroxy-7-oxodehydroabietic acid, was synthesized and identified as a component of Portuguese gum rosin. 7-oxodehydroabietic acid was found to a be a grade III allergen according to the GPMT method. Guinea pigs induced with gum rosin showed only a low response to the isolated compounds, while patients with a known allergy to gum rosin reacted to a greater extent. The results imply that the content of oxidized dehydroabietic acids in gum rosin is too low to give a marked sensitization in the animals. However, the patients might have come in contact with the allergens in technically modified rosins. The compounds showed a pattern of cross-reactivity in the animal experiments as well as among the patch tested patients.
Abietanes↗
Identification of 15-hydroperoxyabietic acid as a contact allergen in Portuguese colophony.
15-Hydroperoxyabietic acid (15-HPA) has been isolated from Portuguese colophony of the gum rosin type and identified as its methyl ester. The structure of the compound was elucidated using UV, IR, NMR and mass spectrometry. 15-HPA methyl ester was found to be an elicitor when tested in colophony-sensitized guinea-pigs. The sensitizing capacity was verified in the same species and 15-HPA methyl ester was considered to be a strong allergen. The eliciting potential was also verified in patients with known allergy to colophony. The Portuguese gum rosin investigated contained approximately 1% of 15-HPA. Based on its allergenicity and the amounts isolated, we conclude that 15-HPA is a main contact allergen in Portuguese gum rosin.
Abietanes↗
Clinical and bacteriological efficacy of amoxycillin/clavulanate (Spektramox) and cefaclor (Kefolor) in children with recurrent AOM or therapy failure.
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Acute Disease↗
Acute traumatic tympanic membrane perforations. Cover or observe?
The influence of a paper prosthesis on healing in acute traumatic tympanic membrane perforations was studied in 60 patients randomly selected for a treatment group or a control group. The majority (42 [70%] ) were seen within two days. All patients were treated with oral antibiotics for ten days. The overall healing rate two months after the trauma was 94% (37 of 39 patients). No significant difference between the study group and the control patients was observed. Intermittent secretion was seen in six patients but did not influence the outcome. The perforations occurred in patients with normally sized mastoid air cell systems as seen on roentgenograms. We conclude that acute traumatic tympanic membrane perforations do not need to be treated routinely with paper patching.
Acute Disease↗
Identification and quantification of arsenocholine and acetylarsenocholine in trace amounts in biological material by use of pyrolysis gas chromatography/mass spectrometry.
An analytical method, based on a selective extraction and pyrolysis gas chromatography/mass spectrometry assay of arsenocholine and acetylarsenocholine in aquatic organisms, is described. Characteristic fragmentation patterns were obtained from pyrolytically demethylated compounds. The molecules were rearranged in unique pathways which differed from those of corresponding nitrogen analogues. Qualitative determination of arsenocholine and acetylarsenocholine was achieved by gas chromatographic as well as mass spectrometric analysis of the thermal degradation products (trimethylarsine, dimethylvinylarsine and the demethylated arsenocholine or acetylarsenocholine). Arsenocholine and acetylarsenocholine in fish from industrially polluted water were isolated and identified. Massfragmentographic quantification of the arsenic compounds in fish was carried out by use of deuterium labelled analogues of arsenocholine and acetylarsenocholine as internal standards. The method showed a high sensitivity.
Animals↗
Psychiatric and psychosocial characteristics of patients accepted for rhinoplasty.
Sixty-four patients undergoing rhinoplasty, consecutively admitted to and operated upon at the Department of Plastic and Reconstructive Surgery, Malmö General Hospital, Sweden, were studied with regard to their medical history, personality, and psychosocial and psychiatric characteristics. Forty patients with a history of nose trauma were compared with 24 patients without such history. The aim of the study was to describe and evaluate background factors, with special regard to psychosocial characteristics that might possibly affect the outcome of rhinoplastic surgery. The trauma patients predominantly described themselves as sthenic, outgoing, self-reliant, insensitive to the opinions of others, and as individuals with a low degree of self-criticism. Their consumption of alcohol was fairly high, and they were often exposed to the risk of accidents with bodily injuries. Their major motive for rhinoplasty was to improve nose breathing. The nontrauma patients were characterized by various symptoms of psychoneurosis and somatic signs of anxiety. Their sensitivity was related to their appearance, and the major motive for rhinoplasty was to become less socially inhibited and to develop their personalities. An inverted factor analysis generally demonstrated that the two groups of patients could be recognized when common response patterns in the preoperative interview formed the basis for the categorization. The psychopathological mechanisms and anticipated adaptation after rhinoplasty are discussed for the two groups of patients.
Adult↗
In vitro and in vivo behavior of 111In-labelled platelets: an experimental study of healthy male volunteers.
The aim of this study was to obtain a critical evaluation of a simple method for labelling platelets with 111In-oxine. All experiments were carried out on healthy volunteers. 65 +/- 7 (SD) % of the platelets in collected blood were labelled and reinjected. As compared to control experiments, only in response to a low final ADP concentration (1.0 mumol/l) did 111In-labelled platelets show reduced in vitro aggregability. The mean platelet volume for 111In-labelled platelets was slightly lower than the mean platelet volume in whole blood. The results for initial platelet recovery and platelet mean lifespan closely agreed with those of other studies in which considerably higher platelet extraction from whole blood was obtained. After injection, the splenic uptake and blood disappearance of 111In-labelled platelets followed a monoexponential function with almost identical rate constants. By compartmental analysis of the equilibration of platelets between blood and spleen, the splenic blood flow was estimated to be 4.8 +/- 1.9 (SD) % of the total blood volume/min; the intrasplenic platelet transit time was 9.7 +/- 1.6 (SD) min, and the exchangeable splenic platelet pool 31 +/- 8 (SD) %. Highly significant relationships were present between the splenic blood flow and the splenic platelet pool size, as well as between the splenic blood flow and the initial platelet recovery. It is concluded that the requirements for adequate interpretation of platelet kinetics are well met with the present method for harvesting and labelling of platelets.
Adult↗
The predictive validity of psychosocial factors for patients' acceptance of rhinoplasty.
Adaptation to rhinoplasty one year postoperatively was studied in 56 patients and the results compared with their preoperative psychosocial profiles. Of the patients, 21 (37%) reported unfavorable experiences with the operation, such as dissatisfaction with the results and/or increased nervous symptoms. Patients dissatisfied with the operational result were more often men who had experienced a nose trauma as an adult. A high consumption of alcohol, poorly established social relations, and an outgoing sthenic attitude were other characteristics. Patients reacting with increased mental symptoms after the operation had expected the operation to result in a substantial change in their general life situation. Their sensitivity regarding the shape of their noses was, in some cases, of a delusional severity. The remaining 35 patients (63%) adapted fairly well to the operation. By a system of different weights given to interview items, it was possible to demonstrate a significant predictive validity of the preoperative psychosocial evaluation with regard to postoperative adaptation. Application of this evaluation technique therefore should increase the possibility of reliably predicting the outcome. Operations on patients not suited to rhinoplasty might be avoided with the application of such a technique.
Adaptation, Psychological↗
Roentgen stereometry in the study of craniofacial anomalies--the state of the art in Sweden.
The paper is a review of ten years' experience with the method for Roentgen Stereophotogrammetric Analysis (RSA) which was presented by Selvik in 1974. The RSA was developed for the study of bone displacement in three dimensions and intended for clinical use. The accuracy of the recordings is about 0.1 degrees for rotations about and 0.05 mm for translations along any one of the three cardinal axes of the head. The method, based on the use of metallic implants, is essentially individual. Some results from our stereometric studies of patients with cleft lip and palate, hemifacial microsomia, craniofacial dysostosis (Crouzon syndrome) and dysgnathia are presented. The recordings concern the direction, the rate, and the amount of articular growth in the craniofacial sutures and the temporomandibular joints (TMJs). The information obtained is thus highly relevant to treatment planning and follow-up in craniofacial anomalies.
Child, Preschool↗
Detecting arterial and venous obstruction in flaps.
Island skin flaps based on the latissimus dorsi muscle were raised in domestic pigs. Flap circulation, maintained only by the vascular pedicle, was monitored by laser Doppler flowmetry, laser photometry, and transcutaneously measured carbon dioxide tension. Both arterial and venous occlusion were accompanied by very low laser Doppler flow values. In laser photometry, the backscattered intensity of light remained unchanged or was slightly increased during arterial occlusion. In response to venous occlusion, however, the light intensity decreased markedly. Transcutaneous carbon dioxide tension increased in both venous and arterial occlusion. When venous outflow pressure was raised incrementally, both the laser Doppler flow value and the total backscattered light intensity fell proportionately. Laser Doppler flowmetry might thus be useful clinically to detect decreased blood flow in transferred flaps, and laser photometry may determine if the decreased flow is related to the arterial or venous side.
Animals↗
Toxicity of polymethylmethacrylate thermodegradation products.
Polymethylmethacrylate was thermally degraded in air at 300 degrees C and the volatile decomposition products studied with gas chromatography-mass spectrometry. The main product was monomeric methacrylate, although many other compounds existed among the products. Electron spin resonance spectroscopy revealed the presence of free radicals. Wistar rats were exposed to the fumes of the plastic (300 degrees C) and their lungs and brain studied for biochemical effects. In the lung, the activity of 7-ethoxycoumarin O-deethylase decreased and an initial inhibition of glutathione peroxidase and superoxide dismutase was observed. The contents of reduced nonprotein sulfhydryl groups were decreased in the lung and brain. The exposures enhanced the activities of acetylcholine esterase, creatine kinase and NADPH-diaphorase in the brain. Scanning electron microscopy of the exposed lungs showed disorganization of ciliated cells, and the epithelial serous cells (Clara cells) were damaged.
Animals↗
Diffuse sclerosing osteomyelitis of the mandible.
The medical care of patients with diffuse sclerosing osteomyelitis (DSO) of the mandible has been unsatisfactory. The main reasons for this have been insufficient knowledge of the disease and its natural history, difficulties in establishing the correct diagnosis, and the unknown etiology. The clinical features and natural history of the disease were studied by means of repeated radiographic and scintigraphic recordings. The biopsy technique was improved by using a slowly rotating coarse trepan bur. Histological and enzyme histochemical investigations were performed for determination of the histopathological diagnosis. Orthopantomograms in combination with intraoral views and 99mTc-scintigraphy were used for the radiographic diagnosis and follow-up studies. Bacteriological and serological investigations were performed in attempt to clarify the obscure etiology. The occurrence in the patients' sera of antibodies to antigens prepared from cultured bacteria was studied. ASTA, IgM, IgG, and IgA were determined and lymphocyte stimulation tests were performed. The investigations made it possible to distinguish DSO as a separate entity with rather characteristic clinical, histological and radiographic features. The histological diagnosis was facilitated by an improved biopsy technique and enzyme histochemical recordings. Different rather unspecific tissue reactions were together found to form a pattern which was strongly indicative of DSO. The radiographic and scintigraphic investigations gave valuable findings which increased the diagnostic accuracy and improved the prognostic and therapeutic judgements. The bacteriological and serological investigations indicated that propionibacterium acnes and peptostreptococcus intermedius were of etiological importance but could not explain the chronicity of the disease. The results of the different investigations gave a better understanding of DSO and made it possible to provide more appropriate care for patients in different stages of the disease. Long-term antibiotic therapy was found to have a positive influence on the course of the disease in its early stages, while cortisone therapy, and sometimes decortication, were found to be more effective in chronic stages.
Adult↗