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Biomedical subjects

B Nyström

Publications and source records attributed to B Nyström.

At least 55 records · Page 3Linked to original sources
PubMed1993

Biochemical correlates to cortical dysplasia, gliosis, and astrocytoma infiltration in human epileptogenic cortex.

The study provides detailed biochemical correlates to the common histopathological diagnoses in epilepsy. A dot immunobinding procedure was used for quantification of NSE, GFA, S-100, NCAM, NF 68 and NF 200. The material consisted of samples from 48 patients either selected for surgical treatment of partial epilepsy or for disorders not related to epilepsy. The histopathological diagnosis of the epileptic cases was: MCD (mild cortical dysplasia, microdysgenesis), gliosis, astrocytoma, ganglioglioma, oligodendroglioma and single cases. The concentration in non-epileptic white matter, in per cent of that in grey matter was: NSE, 85; GFA, 175; S-100, 117; NCAM, 43; NF 68,227 and NF 200, 173. The concentration of NSE as well as of GFA was close to normal in the specimens of the MCD and gliosis groups and of one subgroup of the astrocytomas. There was a striking inverse relationship of the GFA vs the NSE concentrations in the whole material. The concentrations of S-100 showed no such inverse relationship to NSE levels. In all the epileptic groups, total NCAM was lower than 50% of that of the non-epileptic group. The mean NF 68 and NF 200 concentration in the gliosis and astrocytoma groups was 75% of that of the non-epileptic group while the corresponding value for the MCD group was 50%. There was a positive correlation of immunochemically determined GFA and the histopathological gliosis score in the samples of epileptogenic cortex. There was no correlation between the concentration of GFA in the samples and the duration of epilepsy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Co-variation of free amino acids in human epileptogenic cortex.

The concentration of free amino acids was measured in 41 surgically removed samples of human epileptogenic brain and in 7 specimens of non-epileptic brain tissue, removed during surgery for meningiomas, etc. The material was subdivided according to the neuropathological diagnosis: mild cortical dysplasia (MCD), gliosis astrocytoma infiltration and a histologically heterogeneous group. The non-tumoral epileptogenic samples had five times higher than normal concentration of ethanolamine and 50% elevated concentration of glycine. The concentration of other neurotransmitter amino acids did not differ markedly between epileptogenic and non-epileptic samples. The concentration of neurotransmitter amino acids showed a strong correlation with the enzyme neuron specific enolase (NSE) and were low in most samples with astrocytoma infiltration. On the other hand, tyrosine and leucine had higher concentrations in samples with lower NSE concentration. Factor analysis of the amino acids revealed four groups of covarying compounds in the brain samples, first, a neurotransmitter group, including aspartate, glutamate, GABA and phosphoethanolamine. Another group contained ethanolamine, glutamine, glycine and taurine. Factor analysis on corresponding extracellular amino acids showed two groups, the first being a "neurotransmitter" group, containing serine, taurine phosphoethanolamine and ethanolamine in addition to aspartate and glutamate. The other group consisted of asparagine, glycine, alanine, tyrosine, valine, phenylalanine, isoleucine and leucine.

Adolescent↗
PubMed1993

Thoughts on levels of microbial cleanliness and on validating disinfection procedures.

Efforts of the European Committee of Standardization (CEN) and the International Organization for Standardization (ISO) to harmonize production standards for medical devices have brought to the fore the need to standardize definitions and names for different levels of microbial contamination as well as validation procedures for microbial inactivation. Spaulding's categories of medical devices (critical, semi-critical and noncritical items) suggest that different levels of cleanliness can be accepted. Current terminology is imprecise and does not provide the necessary information to the user. A more appropriate one is needed. So are methods to validate microbial inactivation processes to lower levels of cleanliness than sterility. In Sweden, a couple of validation studies have been performed on bacterial inactivation in automatic washing machines which disinfect through a final hot water or steam rinse. However, more studies need to be done, especially on viral inactivation.

Disinfection↗
PubMed1992

Colonization with coagulase-negative staphylococci in two neonatal units.

Episodes of septicaemia due to coagulase-negative staphylococci (CNS) were more frequent in a level III than in a level II neonatal unit in Stockholm, Sweden. Colonization with CNS during the first 2 weeks of life was investigated in 10 infants from each unit. As the use of antibiotics differed between the two units, the aim was to correlate colonization and antimicrobial resistance patterns to antibiotic usage. Antimicrobial susceptibility of CNS to isoxazolylpenicillins, co-trimoxazole, erythromycin, clindamycin, chloramphenicol and gentamicin was determined. Selected isolates were typed with restriction endonuclease analysis of plasmid DNA and of genomic DNA. Infants were frequently colonized with multiple strains and species of CNS, and transmission of strains from patient to patient occurred within the unit. Qualitative and quantitative differences in antibiotic use were not correlated with colonization. The prevalence of resistant isolates, mostly of Staphylococcus haemolyticus, was higher in the level II unit with lower use of antibiotics. Staphylococcus epidermidis, which is generally more virulent, prevailed in the level III unit, where there were more severely ill children and invasive procedures were more frequently performed.

Anti-Bacterial Agents↗
PubMed1992

The role of hospital infection control in the quality system of hospitals.

Like other highly specialized fields, quality systems have their own vocabulary which we must be familiar with; it has been internationally standardized. This standard should be adhered to in order to avoid unnecessary ambiguities and confusion, and to facilitate exchange of information between disciplines. We, in the infection control field, are quality pioneers in hospitals. We have, within our discipline, created quality systems and practised quality surveillance for decades. This must be recognized. Medical quality audits intended for comparisons between hospitals, services and wards require measurable quality criteria and comparable measures for the presence of all relevant patient-related risk factors. To specify quality within our field we need much more detailed information on the effect and cost of infection control practices, as well as the costs of the infections we intend to control. To progress one step further, patients or their representatives, politicians, need to express what monetary value should be put on health, namely freedom from infection and its consequences.

Cross Infection↗
PubMed1992

Hospital-associated infections in obstetrics and gynecology. Effects of surveillance.

STUDY OBJECTIVE: To determine whether continuous surveillance of hospital-associated infections with regular feed-back to the staff reduces the infection rate in obstetrics and gynecology. DESIGN: Two infection control nurses surveyed all patients over a 2-year period for infections and potential risk factors. After an initial 9-month period (period A), quarterly information to all doctors and nurses was introduced for the rest of the study (period B). SETTING: A department of obstetrics and gynecology at a Swedish university hospital. PATIENTS: All patients undergoing surgery, excluding vacuum aspiration abortions and dilatation and curettage. MAIN RESULTS: 2,334 patients were surveyed. In period A, 14.2% of all operations were followed by an infection, compared with 9.5% in period B (p less than 0.001). For purulent wound infections and for endometritis, a significantly reduced rate was noted from period A to B. Several risk factors for infection were significantly more common in period B than in period A. Cesarean sections and hysterectomies were the most common operations also having among the highest infection rates. For both of these operations, infection rates were significantly reduced from period A to period B (from 15.1% to 9.0% and from 15.7% to 10.7%, respectively). The average length of hospitalization was 6 days longer for an infected than for an uninfected patient. CONCLUSIONS: Surveillance of hospital-associated infections including regular feed-back to the staff was accompanied by a significant reduction in infection rates. A quality surveillance program for departments of obstetrics and gynecology therefore seems to benefit from including such surveillance. Surveillance could possibly be limited to only a few common operations with high infection rates.

Cesarean Section↗
PubMed1992

Fatal systemic poisoning after skin exposure to monochloroacetic acid.

Little information is available on the toxicity of monochloroacetic acid. We report the case of a 38 year-old man who was splashed with an 80% monochloroacetic acid solution on 25-30% of his body surface. In addition to epidermal and superficial dermal burns, features of systemic poisoning occurred within a few hours including disorientation, agitation, cardiac failure and coma. He later developed severe metabolic acidosis, rhabdomyolysis, renal insufficiency and cerebral edema, and died due to uncal herniation on d 8. The 4 h post exposure plasma monochloroacetic acid concentration was 33 mg/L confirming skin absorption. In addition to its corrosive action, monochloroacetic acid probably blocks the tricarboxylic acid cycle (Kreb's cycle) and may also react with sulfhydryl groups in enzymes, causing severe tissue damage in energy-rich organs.

Accidents↗
PubMed1991

New technology for sterilization and disinfection.

Sterilization with low temperature steam and formaldehyde is a well-known process in many European countries, but little known in the United States. It sterilizes reliably and reproducibly at temperatures greater than or equal to 65 degrees C. With a well-designed cycle, it leaves residues of formaldehyde on sterilized items below 5 micrograms/cm2, measured on a standard filter paper. Formaldehyde levels in air near the autoclave are well below official exposure limits, if at all measurable. Occurrence of late growers in bioindicators, and penetration of the sterilizing media into long narrow lumina, should be validated for new processes. Automated cleaning and disinfection in closed washer-disinfectors and flushing disinfectors are likewise processes relatively little known in the United States. Disinfection is achieved by a final rinse with hot water or steam. Washer-disinfectors are used for surgical instruments, nondisposable anesthesia and other equipment, flushing disinfectors for nondisposable bedpans, wash-bowls, urinals, and similar equipment. They clean well, washer-disinfectors excellently so, and disinfect reliably. With the use of such equipment in wards, surgical departments, and other areas, reliance on chemical germicides can be dramatically reduced and disposables can be replaced by disinfectable nondisposables.

Disinfection↗
PubMed1991

Infection control policies and guidelines--Scandinavian experience.

In the Scandinavian countries few regulations govern hospital infection control. In Sweden a common procedure manual is used nationwide, consisting of guidelines covering a wide range of nursing and medical procedures performed by the nursing staff. It is revised every fifth year. A recent enquiry to over 150 wards in some 100 hospitals demonstrated that the manual is widely accepted and used. In the other Scandinavian countries, guidelines and policies on a variety of infection control topics have been published.

Clinical Protocols↗
PubMed1991

Microdialysis sampling of the neuronal environment in basic and clinical research.

Microdialysis is a technique for sampling extracellular fluid (ECF) which has been employed in brain research for about 10 years, and is now in experimental and clinical use in a number of biomedical disciplines. We report on microdialysis of neuroactive amino acids in the central nervous system (CNS) and discuss some technical problems of microdialysis, such as tissue reactions, calibration and the difficulties involved, as well as strategies for determination of the true extracellular concentration of various compounds. Possible mechanisms of nerve cell death in ischaemia and hypoglycaemia are among the factors that have been elucidated using data obtained by microdialysis. The neuronal environment overflows with excitatory amino acids both in brain ischaemia and in hypoglycaemia.

Animals↗
PubMed1991

On the prevention of caries and periodontal disease. Results of a 15-year longitudinal study in adults.

In 1971-72, a total of 375 adult subjects were recruited for a clinical trial aimed at assessing the effect of a preventive program, based on plaque control and topical application of fluoride, on the incidence of caries and periodontal disease. After a baseline examination, the volunteers were subjected to scaling, root planning and conventional caries therapy. During the course of the subsequent 6 years, they were recalled for preventive measures once every 2-3 months. After the 6-year follow-up examination, however, it was decided to extend the interval between the preventive sessions. Thus, during the next 9-year period, about 95% of the participants returned for preventive measures only 1 to 2 times per year. A small subgroup of about 15 subjects, who, during the initial 6 years had developed new caries lesions or had exhibited additional periodontal attachment loss, however, were also during the following 9 years recalled 3-6 times per year for oral hygiene control and preventive therapy. The re-examination performed in 1987 disclosed that the 317 subjects, who participated during the entire 15-year period, had a low incidence of caries and almost no further loss of periodontal tissue support. It was suggested that improved self performed oral hygiene, daily use of fluoridated dentifrice and regularly repeated professional tooth cleaning effectively prevented recurrence of dental disease.

Adult↗