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Biomedical subjects

H Pihko

Publications and source records attributed to H Pihko.

At least 91 records · Page 5Linked to original sources
PubMed1976

Characterization of homologous anti-alpha-fetoprotein antibodies produced in rabbits.

The natural tolerance to alpha-fetoprotein (AFP) was broken in rabbits by immunizations with purified AFP from different species and homologous AFP chemically modified by haptenation. Some of the rabbits were boostered with rabbit AFP. The highest titers were obtained with human AFP, which shows a strong cross-reaction with rabbit AFP. The homologous antibodies were of lower avidity than heterologous (sheep) antisera. Injections with rabbit AFP did not alter the avidity or titer. All antibodies produced by injections with human AFP could be absorbed with the original immunogen, and no reactivity against determinants unique to rabbit AFP could be found. These results indicate that the antibody activity against autologous AFP is based on cross-reactivity and that the immunizations did not make the autologous AFP immunogenic. These findings may be important in view of the possible use of AFP as a target antigen in tumor immunotherapy.

Animals↗
PubMed1975

Carcinoembryonic antigen and alpha fetoprotein in malignant tumors of the female genital tract.

Circulating carcinoembryonic antigen (CEA) and alpha fetoprotein (AFP) levels were measured by radioimmunoassay in 53 patients with carcinoma of the ovary, 16 patients with other malignant genital tumors, and 31 women with nonmalignant diseases of the genital tract. The serum CEA concentration was elevated (greater than 5 ng/ml) in 11 patients with ovarian cancer, 2 patients with endometrial cancer, 1 patient with carcinoma of the cervix, and 1 patient with a benign embryonal cystic teratoma. Elevated CEA levels were found only in patients with advanced malignant disease, while early stages were associated with normal CEA concentrations. AFP levels were normal in all but 1 patient. Both CEA and AFP levels were markedly raised in a case of advanced genital carcinoma arising probably from the ovary. Ascitic fluid of another patient with ovarian cancer contained a high concentration of CEA, giving an identical reaction in immunodiffusion with CEA from colon cancer. The present results indicate that while the increased expression of carcinofetal components takes place in some malignant tumors of the female genital tract, it is usually a late phenomenon.

Alpha-Globulins↗
PubMed1975

Rabbit alpha-fetoprotein: normal levels and breakage tolerance with haptenated homologous alpha-fetoprotein.

Nanogram quantities of alpha-fetoprotein (AFP), a tumor associated fetal protein, were found in the serum of normal adult rabbits by radioimmunoassay. This AFP was isolated and shown to be immunologically identical to fetal AFP by immunodiffusion. Immunizations of rabbits with unmodified to desialylated AFP in complete Freund's adjuvant did not cause antibody formation, indicating the existence of tolerance against homologous AFP. The tolerance could be terminated by immunizing with hapten-coupled AFP, which resulted in production of rabbit antibodies reacting with unmodified rabbit AFP.

Animals↗
PubMed1974

Serum alpha-fetoprotein: diagnostic significance in liver disease.

Raised serum alpha-fetoprotein levels measured by radioimmunoassay were found in 19 out of 24 (79%) patients with primary liver cancer and in 32 out of 311 (10%) patients with other liver diseases. The rise was transient in cases of hepatitis and a transient rise was also seen after alcohol intake ceased in two patients with cirrhosis. alpha-Fetoprotein levels exceeding 500 ng/ml were 30-50 times more common in primary liver cancer than in other liver diseases. A rise in level seems to reflect the extent of liver regeneration in liver diseases other than primary cancer.

Biopsy↗
PubMedDate not supplied

Brain perfusion SPECT in children with frequent fits.

We studied 14 children with frequent fits using 99mTc-HM-PAO single photon emission computed tomography (SPECT). There were 11 patients with partial secondary generalized epilepsy (PSGE) and 3 with Lennox-Gastaut syndrome (LGS). The typical regional cerebral blood flow (rCBF) finding in PSGE was a single area of abnormally low perfused cortex, and that in LGS, multiple hypoperfused areas. Clinically, the LGS patients were more severely affected. SPECT was more sensitive in detecting abnormalities than EEG, CT or MRI. Extensive impairment of rCBF may thus indicate unfavourable development of intellectual performance and poor seizure control.

Adolescent↗
PubMedDate not supplied

Ocular findings in muscle-eye-brain (MEB) disease: a follow-up study.

We present ocular findings of 20 patients with the recessively inherited muscle-eye-brain (MEB) disease, characterised by severe visual failure, mental retardation, a pachygyria-polymicrogyria type neuronal migration disorder and congenital muscular dystrophy. The ocular findings consisted of myopia ranging from -6 to -27 D, retinal degeneration and optic atrophy. Five infants had congenital glaucoma, and juvenile cataracts developed in 9 children. The visual evoked potentials were abnormally high (> 50 microV) and delayed in 70% of patients. The electroretinogram was abolished in 12 patients. The changes were progressive during the follow-up time, which was up to 20 years.

Adolescent↗
PubMedDate not supplied

Wernicke encephalopathy--a preventable cause of death: report of 2 children with malignant disease.

Wernicke encephalopathy is a disorder caused by a deficiency of thiamine which is a cofactor of several metabolic enzymes. The symptoms include mental confusion, ataxia, and ocular signs in adults, infants, and children. Patients often have somnolence and weakness combined with ophthalmoplegia. Alcoholics are the best known risk group; however, Wernicke encephalopathy occurs in poorly nourished patients of all ages. We present 2 children with malignant disease in whom Wernicke encephalopathy--an underdiagnosed and potentially fatal, but preventable and treatable disease--was diagnosed postmortem.

Child↗
PubMedDate not supplied

Chemotherapy with the "8 in 1" protocol for malignant brain tumors in children: a population-based study in Finland.

We evaluated the outcome of 68 children with malignant brain tumors treated with the "8 in 1" chemotherapy protocol in Finland from 1986 to 1993, comparing 5-year survival rates with those for a historical control group (from 1975 to 1985). For all malignant brain tumors, overall survival was 43% (vs 28% in the control group; P <0.05), and progression-free survival (PFS) was 43% (vs 23%; P <0.05). For medulloblastoma and primitive neuroectodermal tumor, survival was 63% (vs 35%; P <0.05), and the corresponding PFS was 59% (vs 35%; P = 0.15). For high-grade glioma, both the survival rate and the PFS were 27% (vs 17%; P = NS). Thus the outcome was significantly better for our "8 in 1" -treated patients than for the historical controls, especially among the children with primitive neuroectodermal tumor and medulloblastoma. In contrast, those with high-grade gliomas and brain stem tumors seem to have received little benefit; different, more effective treatments are needed for these patients.

Adolescent↗
PubMedDate not supplied

PEHO syndrome (progressive encephalopathy with edema, hypsarrhythmia, and optic atrophy): neuroradiologic findings.

PURPOSE: To investigate the radiologic characteristics of the clinical progressive encephalopathy with edema, hypsarrhythmia, and optic atrophy (PEHO) symptom complex. This complex is nonspecific, but within this syndrome, a subgroup with a defined neuropathologic phenotype and apparently autosomal recessive inheritance exists. METHODS: Brain CT or MR studies were performed on 21 patients with the clinical PEHO syndrome. Their previous neuroradiologic studies were re-evaluated. RESULTS: Twelve patients (group A) showed uniform changes with early progressive brain atrophy accentuated infratentorially, and abnormal myelination. The gyral pattern was normal. Brain atrophy of nine patients (group B) differed by being less progressive, supra- rather than infratentorial, and often combined with abnormal gyral formation. CONCLUSIONS: Postmortem studies permitted correlation of radiographic and morphologic findings in three cases. Two autopsied group A patients were compatible with the true PEHO syndrome, while one group B patient was incompatible. Group A seems to correspond to the core group of the PEHO syndrome. During a patient's life, a suggestive diagnosis of the true PEHO syndrome is thus feasible, although neuropathologic studies are needed for a conclusive diagnosis.

Brain Diseases↗