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P Nevalainen

Publications and source records attributed to P Nevalainen.

4 recordsLinked to original sources
PubMed2006

Trigeminal somatosensory evoked magnetic fields to tactile stimulation.

OBJECTIVE: To characterise the activation of the contra- and ipsilateral primary somatosensory cortex (SI) after tactile stimulation of the face. METHODS: Trigeminal somatosensory evoked magnetic fields (TSEFs) were recorded after tactile stimulation of the lower lip, cheek, chin and forehead in 11 healthy subjects. The responses were determined visually from the waveforms and modelled with equivalent current dipoles (ECDs). RESULTS: Contralateral SI responses were evoked in all subjects after lip stimulation, and in 91% and 64% after right and left cheek, 73% and 82% after chin and 64% and 27% after forehead stimulation. The responses usually showed an early double-peak wave pattern, the underlying sources localising to the SI. In addition, altogether 37 ipsilateral SI responses were evoked in eight subjects. Fourteen of these responses were amenable to ECD modelling and localised to ipsilateral SI. CONCLUSIONS: Tactile stimulation of the lip area reliably activates the contralateral SI in normal subjects, but the success rate for other trigeminal areas is lower. Ipsilateral responses can be present after stimulation of any of the trigeminal branches in normal subjects. SIGNIFICANCE: Recording of TSEFs after tactile stimulation of particularly the lip area provides a non-invasive technique to study the function of the trigeminal nerve.

Adult↗
PubMed1997

The influence of peritoneal dialysis and the use of subcutaneous and intraperitoneal insulin on glucose metabolism and serum lipids in type 1 diabetic patients.

BACKGROUND: Intraperitoneally administered insulin is regarded as the most physiological replacement therapy, leading to lower peripheral insulin concentrations and equal or better glycaemic control than subcutaneous insulin. This two-part study was undertaken to evaluate the effect of CAPD, as well as the use of subcutaneous vs. intraperitoneal insulin on insulin sensitivity, glycaemic control and serum lipids in type 1 diabetes. METHODS: Eleven patients with type 1 diabetes mellitus and chronic renal failure participated the studies. Glycated haemoglobin (HbA1c), euglycaemic hyperin-sulinaemic clamp, serum lipids, and patient well-being were measured. During CAPD all patients were first treated with subcutaneous insulin and then with intraperitoneal insulin. The metabolic studies were repeated after both treatment periods for at least 3 months. Metabolic studies were performed on six of the patients also before initiation of CAPD. RESULTS: HbA1c rose after the initiation of CAPD from 8.85 +/- 0.54% to 9.58 +/- 0.66%, NS) and improved after changing from subcutaneous to intraperitoneally administered insulin (from 9.49 +/- 0.43% to 8.13 +/- 0.39%, P < 0.01). Insulin dose increased by 15% after initiation of CAPD and 128% after switching from subcutaneous to intraperitoneal insulin. Glucose disposal rate enhanced by 39% (P = 0.05) and 14% respectively (P < 0.01). Initiation of CAPD had no significant effects on serum lipids but intraperitoneally administered insulin reduced HDL cholesterol and increased LDL/HDL ratio significantly. CONCLUSIONS: Intraperitoneal insulin therapy offers better glycaemic control and insulin sensitivity than subcutaneous insulin. Deterioration of HbA1c after initiation of CAPD while patients remained on subcutaneous insulin may be partly due to absorbed energy from the dialysate. Intraperitoneal insulin therapy seems to have detrimental effects on serum lipids. The clinical significance in modifying the risk of atherosclerosis remains unclear.

Adult↗