Biomedical subjects

J Klos

Publications and source records attributed to J Klos.

At least 19 recordsLinked to original sources

PubMed2004

Lattice Monte Carlo simulations of three-dimensional charged polymer chains.

The configurational properties of strongly charged polyelectrolytes accompanied by neutralizing counterions in dilute solutions are simulated using the cooperative motion algorithm on the face-centered-cubic lattice. The full Coulomb potential and the excluded volume condition between different ions/beads are taken into account and the reduced temperature T* is considered the main, variable parameter. The calculations that have been carried out for solutions of both single and several chains indicate a few regions of their behavior: (1) for T*--> infinity, it corresponds to that of neutral, self-avoiding polymers under good solvent conditions; (2) for T* approximately 1, due to the electrostatic interactions being effectively stronger, the chains are more outstretched compared to their size at other temperatures; (3) for T* well below one, the counterion condensation becomes more and more dominant, which gradually leads to strongly collapsed chains; and (4) at the lowest temperatures the chains and counterions assume low-energy configurations in the form of neutral, compact aggregates.

Journal Article↗

PubMed2004

Lattice Monte Carlo simulations of three-dimensional charged polymer chains. II. Added salt.

The configurational properties of strongly charged polyelectrolytes accompanied by counterions and salt ions in dilute solutions are simulated using the cooperative motion algorithm on the face-centered-cubic lattice. The calculations indicate that both positive and negative ions condense on the chains at sufficiently low temperatures and their amount depends on the concentration of added salt. As the temperature decreases from high to low, the chains undergo conformational changes from neutral-like, self-avoiding polymers by more outstretched forms to compact globules. The observed extension of the chains at intermediate temperatures is also affected by the amount of salt. Furthermore, configurations with the lowest energies recorded at the lowest temperatures are aggregates of single or more entangled chains and ions of both types.

Journal Article↗

PubMed1999

Effect of a standard exercise protocol on shoulder pain in long-term wheelchair users.

PURPOSE: To analyze the effectiveness of a 6-month exercise protocol on shoulder pain experienced by wheelchair users during functional activities. SUBJECTS: Forty-two wheelchair users, 35 males and seven females: average age of 35 years and an average duration of wheelchair use of 14 years. METHODS: Subjects were randomly assigned to treatment (n=21) and control (n=21) groups. The treatment group received instruction in five shoulder exercises which they performed daily for 6 months. The exercise protocol included two exercises for stretching anterior shoulder musculature and three exercises for strengthening posterior shoulder musculature. OUTCOME MEASURES: All subjects completed a self-report questionnaire and the Wheelchair Users Shoulder Pain Index (WUSPI) initially and at bimonthly intervals during the 6-month intervention. RESULTS: Seventy-five per cent of the subjects reported a history of shoulder pain since beginning wheelchair use. The average initial performance-corrected (PC-WUSPI) score of the 42 subjects was 17.7 (+/-21.3) with a range of 0-103.2 points. Over 83% of the subjects (35 of 42) completed the 6-month study. Subjects in the treatment group decreased their PC-WUSPI score by an average of 39.9%, compared to decreases of only 2.5% in the control group. CONCLUSIONS: These findings supported the effectiveness of this exercise protocol in decreasing the intensity of shoulder pain which interferes with functional activity in wheelchair users.

Adult↗

PubMed1990

[Persistent neonatal hypoglycemia in nesidioblastosis of the pancreas].

A now 10 month old female infant suffered from persistent non ketotic neonatal hypoglycemia despite continuous intravenous application of glucose (greater than 10 mg/kg/min). There was only a transient response of blood glucose after intravenous administration of glucagon and prednisolon. Biochemical findings indicated hyperinsulinismus (insulin level of 26 mE/ml during hypoglycemia). Oral diazoxid treatment in high doses (22 mg/kg) stopped hypoglycemia episodes for several days but the newborn remained glucose infusion depended. Finally the treatment had to be interrupted because of vomiting. At the age of 4 1/2 weeks a subtotal pancreatectomy was performed. The histological examination of the pancreas confirmed the clinically suspected diagnosis of nesidioblastosis. After pancreatectomy the infant required insulin therapy. Since six months the girl is without insulin in a good condition. Despite periods of arrested head growth before pancreatectomy the psychomotoric development is normal.

Blood Glucose↗

PubMed1982

Primary small cell (oat cell) carcinoma of the larynx associated with an IgD multiple myeloma.

Primary small cell (oat cell) carcinoma of the larynx is a rare condition. We report a case of primary oat cell carcinoma of the subglottic larynx associated with a synchronous IgD multiple myeloma (an unreported association). An increased incidence of carcinoma associated with plasma cell disorders has been reported, and the theories of this association are discussed. In a review of the reported cases, the most successful management of oat cell carcinoma of the larynx appears to incorporate a combination of radiotherapy and chemotherapy. Our case was treated with a combination of protocols used for oat cell carcinoma of the larynx and multiple myeloma. At 24 months after diagnosis, the patient is free of oat cell carcinoma, and the multiple myeloma is under control.

Carcinoma, Small Cell↗

PubMed1981