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Biomedical subjects

G K Jacobsen

Publications and source records attributed to G K Jacobsen.

105 records · Page 6Linked to original sources
PubMed1981

An immunohistochemical study of a series of plasma proteins in the early human conceptus.

A 20-day-old human conceptus was studied by the indirect immunoperoxidase technique for the presence of a series of plasma proteins: prealbumin (PA), albumin (ALB), alpha-fetoprotein (AFP), alpha 1-antitrypsin (A1AT), carcioembryonic antigen (CEA), immunoglobulin G (IgG), ferritin (FER), transferrin (TR), fetal haemoglobin (HbF), human chorionic gonadotropin (HCG), human placental lactogen (HPL) and pregnancy specific beta 1-glycoprotein (SP1). In the embryo only FER and TR were found. The yolk sac was positively stained for several proteins: PA, ALB, AFP, A1AT, IgG, FER, TR and HbF were demonstrated in the endodermal cells and PA, ALB, IgG and TR in the mesothelial cells. The syncytiotrophoblast of the chorionic villi were heavily stained for all the placental proteins. HCG and HPL were additionally demonstrated in the cytotrophoblast. The Hofbauer cells of the chorionic and villous stroma stained positively for A1AT and FER. TR appeared as a characteristic band on the apical surface of the syncytiotrophoblast. The findings indicate that the yolk sac is the principle source of some of the plasma proteins also in the very early conceptus and the assumption that the yolk sac is the functional antecedent of the liver is supported. The distribution of the various placental proteins is in accordance with the present knowledge that the syncytiotrophoblast is the major site of synthesis of these proteins. Finally correlation of functional aspects of embryonic structures and germ cell tumours is recommended.

Blood Proteins↗
PubMed1981

Mammography directed wire marking of nonpalpable breast lesions. A consecutive biopsy study of 100 patients.

Among 665 patients referred for breast complaints, 100 women (15%) had mammographically detected nonpalpable lesions suspected of malignancy. Using a mammography directed hook wire marking, 115 excisional biopsies were carried out. A correct biopsy containing the lesion was obtained in 113 instances. There were 2 failures, due to displacements of the wire in one case and surgical inexperience in another case. Two patients had minor wound complications. Invasive carcinoma was found in 12 and carcinoma in situ in 4 biopsies, i.e., a cancer rate of 16% of patients and 14% of biopsies. The biopsy procedure was simple, time saving, and acceptable of patients. The excisions were small and the cosmetic results excellent. During mammography for control of wire position, and during dressing and surgical manipulations the flexible hooked wire remained as originally placed in all cases but one.

Adult↗
PubMed1979

Immunohistochemical evidence for an intracellular localization of plasma proteins in human foetal choroid plexus and brain.

The intracellular distribution of plasma proteins in human foetal choroid plexus and brain was investigated by immunohistochemistry. Small groups of cells or single scattered cells in the epithelial layer of the choroid plexus exhibited positive staining for alpha-fetoprotein, albumin and transferrin, whereas prealbumin was found in the majority of the epithelial cells. Numerous nerve cells in the cerebral wall and in various brain stem nuclei were positively stained for alpha-fetoprotein, albumin and prealbumin. All appropriate controls were negative. The presence of plasma proteins within choroid plexus epithelial cells suggest that these proteins are transported from blood to CSF by a transcellular route across the choroid plexus epithelium. The intracellular distribution of plasma proteins in developing neurons may indicate that these proteins play some important role in neuronal differentiation or development.

Blood Proteins↗
PubMed1979

Effects of thymus grafts in nude mice transplated with human malignant tumors.

The effect of neonatal thymus grafts implanted in nude mice previously transplanted with three different human malignant tumors - an adenocarcinoma of the colon, a malignant melanoma and a Burkitt's lymphoma - were studied. In all immunologically reconstituted animals tumord were rejected. Tumor rejection stated 2-3 weeks after thymus implantation, and was completed after 30-6 weeks. Histological examination of lymphoid tissues showed a correlation between immunological reconstitution and tumor rejection. The rejection process showed a characteristic histologic picture with 3 phases - an early, an intermediate and a late phase - these were similar in the three tumor types examined. The possible mechanisms of reconstitution and tumor rejection are discussed.

Adenocarcinoma↗
PubMed1977

Ultrastructural changes in disseminated connective tissue nevi.

Skin biopsy specimens from a patient with disseminated connective tissue nevi and from her son and daughter who had no such clinical alterations were studied with the electron microscope. The nevi showed increased amounts of thick elastic fibres, which were composed of irregularly arranged, often finger-like, subunits surrounded by a thready material. Both structures probably represent malformed components of elastic fibres, the thready material representing malformed elastic fibrils. Many of the collagen fibrils showed increased diameters and twistings, which alterations are believed to represent malformation of collagen. The fibroblasts showed changes which might be related to a pathological protein synthesis. Examination of biopsy specimens from normal skin of the patient and from the skin of her son and daughter failed to demonstrate similar alterations. The present case is regarded as an entity, distinct from dermatofibrosis lenticularis disseminata and from shagreen patch.

Adult↗
PubMed1975

Chemotherapy of a human malignant melanoma transplanted in the nude mouse.

The effects of single agent therapy with 1-(-chloroethyl)-3-cyclohexyl-1-nitrosourea, 5-fluorouracil, and 5-(3,3-dimethyl-1-triazeno)-imidazole-4-carboxamide on a human malignant melanoma transplanted and passed serially in thymusless nude mouse were studied. Tumor response varied. A single dose of 1-(-chloroethyl)-3-cyclohexyl-1-nitrosourea induced initial tumor regression, but thereafter growth resumed at a rate similar to that in the untreated control animals. Wehn 1-(-chloroethyl)-3-cyclohexyl-1-nitrosourea was given in divided dosage at an interval of 8 days, marked and persistent tumor regression was observed. 5-Fluorouracil had no effect. Treatment with 5-(3,3 dimethyl-1-triazeno)-imidazole-4-carboxamide was always reflected by almost total regression of tumors, an effect that was independent of dose within the range tested in this study. The results resemble those reported from clinical practice in patients with disseminated malignant melanomas treated with the same agents. This suggests that the pattern of drug susceptibility is preserved after transplantation of tumors in the nude mouse. The human tumor-nude mouse system is advocated as a new in vivo model for determination of individual tumor response to chemotherapeutic agents, and its potential as a model for the proving of new chemotherapeutic agents is suggested.

Animals↗
PubMedDate not supplied

Metallothionein expression in placental tissue in Menkes' disease. An immunohistochemical study.

Menkes' disease is a recessive X-linked disturbance of copper metabolism, resulting in accumulation of copper in several extra-hepatic tissues including the placenta. Metallothionein (MT) is a low-molecular weight protein with a high affinity for group II metal ions, such as copper. Its synthesis is induced by the presence of the ions. The aim of this study was to investigate the pattern of the MT immunoreactivity in placental tissue obtained from women at-risk of Menkes' disease in order to examine whether the MT occurrence and distribution may reflect the copper content. Placental tissue from six women with a family history of Menkes' disease, from 4 women without a family history, and from 2 hydatiform moles was studied. Positive MT immunostaining was found to be independent of the length of fixation, whether the tissue samples were fixed in 4% buffered formaldehyde or Bouin's fixative. The avidin-biotin-complex (ABC)-technique was used. The copper content was measured by neutron activation analysis (NAA). In all placental tissue sections positive MT immunostaining appeared only in the trophoblast and only in proliferating cells. In placental tissue sections obtained from foetuses and children affected by Menkes' disease an additional MT immunostaining appeared in the Hofbauer cells of the chorionic villi. This staining was associated with an increased content of copper as measured by NAA. We conclude that the immunohistochemical demonstration of MT reflects the copper content and may be useful in pre- and postnatal diagnosis of Menkes' disease.

Female↗
PubMedDate not supplied

Primary paraganglioma of the lung. Report of two cases and review of the literature.

Two cases of primary paragangliomas of the lung are presented. The first occurred in a 69-year-old woman and was a grossly and histologically benign tumour. The other case occurred in a 33-year-old woman who had metastases to the peribronchial lymph nodes. This seems to be the second malignant case reported. No evidence of recurrence nor metastatic disease was found at follow-up, 8 months for the first case and 7 years for the second, respectively. The morphological and immunohistochemical findings are discussed and the literature comprising 20 cases is reviewed.

Aged↗
PubMedDate not supplied

Testicular germ cell tumors. Classification based on fine needle aspiration biopsy.

Fine needle aspiration (FNA) biopsy was performed preoperatively on 13 patients with testicular germ cell tumors. The cytologic typing of the tumors was based on the presence or absence of seminoma, embryonal carcinoma, yolk-sac tumor, choriocarcinoma and teratoma in the aspirate. The cytologic findings showed good agreement with the histologic findings. Only four cases showed a single type of tumor; the other nine cases showed as many as four different tumor components. A few characteristic cytologic features proved to be sufficient for tumor typing; this suggests that FNA biopsy cytology can also be useful in identifying metastatic germ cell tumors in extra-gonadal sites.

Biopsy, Needle↗
PubMedDate not supplied

Coarse needle biopsy versus fine needle aspiration biopsy in the diagnosis of focal lesions of the liver. Ultrasonically guided needle biopsy in suspected hepatic malignancy.

In 55 patients with ultrasonically demonstrated suspected hepatic malignancy, a fine needle aspiration biopsy and a coarse needle biopsy of the same focal lesion were performed under ultrasonic guidance. In 41 of 48 cases with proven malignancy, both biopsies were positive. In the remaining seven cases, only the fine needle aspiration biopsy yielded malignant cells. Tumor typing was possible in 2 primary and 33 metastatic tumors by examination of either the cytologic or the histologic specimen; an additional 6 metastatic tumors could be typed only by evaluation of the histologic specimen. Grading of six adenocarcinomas was performed with higher accuracy in the histologic than in the cytologic specimen. Exact determination of the primary site was not possible in metastatic tumors by use of either type of needle biopsy specimen. Since the less traumatic fine needle aspiration biopsy requires fewer prebiopsy precautions and has other advantages, the coarse needle biopsy should be restricted to the few cases in which the former does not yield sufficient information.

Adenocarcinoma↗
PubMedDate not supplied

A fetus with Down syndrome and intratubular germ cell neoplasia.

A 22-week-old fetus with trisomy 21 demonstrated intratubular germ cell neoplasia. This is the second report of in situ testicular neoplasia in a fetus with trisomy 21, suggesting that the mechanism responsible for the possible excess of testicular germ cell tumors that occur in Down syndrome is operative in early fetal life. Because no examples of neonatal testicular germ cell tumor in trisomy 21 have been reported, we suggest that this in situ neoplasm may disappear during gestation, such as the trisomy 21-associated transient myeloproliferative syndrome does shortly after birth. This disappearance may be due to a controlled regression phenomenon.

Adult↗