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S Kessler

Publications and source records attributed to S Kessler.

At least 73 records · Page 4Linked to original sources
PubMed1996

[Self concept and object relations in patients with monopolar and neurotic depression: a clinical study with the Giessen Test].

A psychodynamic concept of depression is presented which refers to object-relation-theory. It is hypothesized that there is a dynamic interrelationship between the narcissistic homeostasis and interpersonal mechanisms of defence and compensation. The perception of the self and objects of patients with unipolar and neurotic depression and their partners was compared by means of the Giessen-Test. Both clinical groups differ according to the complement of roles and to projective mechanisms of defence. The depression of male patients collides with gender role stereotypes, which are stressed by the self images of depressive women. With regard to therapeutical interventions it is recommended to take into consideration the psychodynamic and interpersonal dimension of depression as well as the conflict resulting from the social-psychological dimension of depression, especially those of depressive male patients.

Defense Mechanisms↗
PubMed1995

Sterilization of partially demineralized bone matrix: the effects of different sterilization techniques on osteogenetic properties.

Transplantation of allogenic bone requires the thorough examination of donors as well as the careful processing and storage of samples in order to minimize potential infection. Other problems associated with allogenic transplants such as low osteoinductive properties and immunological reactions led to the development of partially demineralized bone matrix (PDBM). This highly osteogenic bone extract is largely free of antigens and easy to produce. However, in order to exclude the potential risk of infection, PDBM should be sterilized prior to implantation. It was the purpose of this study to investigate the influence of various sterilization techniques on the osteoinductive properties of PDBM. Seventy-six drill defects with a diameter of 0.6 cm in the tibia of 11 Merino sheep were filled with PDBM as well as autogenic or allogenic cancellous bone. Prior to implantation the PDBM was sterilized using autoclavation, gamma irradiation, ethylene oxide, or ethanol. Twelve empty drill holes served as controls. The extent of new bone formation was ascertained by histological, fluorescent-optical, and microradiographical examinations 3 and 6 weeks postoperatively. Furthermore, the amount of newly formed bone was measured quantitatively. Apart from autoclaved PDBM, all matrix grafts showed excellent new bone formation after sterilization, exceeding the results of allogenic cancellous bone.

Animals↗
PubMed1995

Primary malignant mesenchymoma of bone: case report, literature review, and distinction of this entity from mesenchymal and dedifferentiated chondrosarcoma.

The seventh case of primary malignant mesenchymoma of bone is reported. It is compared to the other six cases in the literature and clinicopathologic pattern of this entity is developed. Primary malignant mesenchymoma of bone is compared to mesenchymal chondrosarcoma and dedifferentiated chondrosarcoma. Differences as well as similarities are discussed and a more current classification scheme for malignant mesenchymoma of bone is proposed.

Bone Neoplasms↗
PubMed1995

Measurement of femoral anteversion by magnetic resonance imaging--evaluation of a new technique in children and adolescents.

Anteversion of the femoral neck was measured by magnetic resonance imaging (MRI) in 19 children (37 hips) preoperatively before femoral rotation osteotomies. The results of this new technique were compared with values for anteversion obtained by computed-tomographic (CT) scanning and ultrasound. In order to determine the correlation between the three different methods and to assess their reliability, the measurements were performed independently by two observers at different times. There was a high correlation (Pearson's correlation coefficient) between MRI results and CT scan (r = 0.77) as well as MRI and sonography (r = 0.81), although the mean anteversion angles obtained by computerized tomography (34.0 degrees, range 5-82 degrees) and ultrasound (25.6 degrees, 10-40 degrees) were larger than the MRI values (23.2 degrees, 0-65 degrees), which can be explained by the different measurement techniques. Mean inter-rater as well as intra-rater reliability was high for MRI (r = 0.97 and r = 0.97) and CT (r = 0.99 and r = 0.96) but slightly less for sonography (r = 0.88 and r = 0.88). MRI is a novel method for evaluating femoral anteversion that does not require ionizing radiation, allows a precise anatomical measurement and reliable results. MRI is recommended for preoperative planning of pediatric femoral rotation osteotomy cases.

Adolescent↗
PubMed1994

[Effect of heredity and environment in immune diseases. Presentation of twin data].

BACKGROUND: The study of twins is an important and informative tool in the investigation of the influence of genetic and environmental factors on the pathogenesis of familial traits. MATERIAL: Seven diseases were analysed by carrying out an intensive study of the literature to search for concordance of monozygotic and dizygotic twins. Apart from single case studies, large unselected series have been reported, some of which show considerable differences in concordance rates. Data from twins were collected for myasthenia gravis, systemic lupus erythematosus, rheumatoid arthritis and type 1 diabetes mellitus, Crohn's disease and, for comparative purposes, also type 2 diabetes mellitus. RESULTS: On the basis of the above-mentioned calculated concordance rates, differences in the influence of genetic factors were established, which may be of importance for the genetic counselling of affected families. These findings based on twins also confirm the multifactorial inheritance model.

Adolescent↗
PubMed1994

Case report 823: Fibro-osseous pseudotumor of the scapula.

A unique lesion discovered in the scapula of a 36-year-old woman is presented. The lesion has microscopic features resembling those of fibrous dysplasia and osteoid osteoma which we believe is identical to an entity previously only documented in the rib (fibro-osseous lesion of rib). We are of the opinion that the lesion probably represents a reactive response to trauma rather than a neoplasm and suggest the name of "fibro-osseous reparative pseudotumor" for this entity.

Adult↗
PubMed1994

Primary osteosarcoma of the penis.

We report a case of an 84-year-old man with extraskeletal osteosarcoma of the penis arising within heterotopic bone. Extraskeletal osteosarcoma of the penis is an exceedingly rare entity; only two other well-documented cases have been reported in the English-language literature.

Aged↗
PubMed1994

Poor transduction efficiency of human hematopoietic progenitor cells by a high-titer amphotropic retrovirus producer cell clone.

The transduction efficiency of human bone marrow CD34+ cells with supernatants from the retrovirus producer cell clone PA317/LGSN 16 was only one-fifth of that with supernatants from GP+ envAm12/LGSN 15, even though both producers had similar infection titers on 3T3 cells. PA317/LGSN 16-conditioned medium inhibited the proliferation of the bone marrow CD34+ cells, and this inhibitory effect was partially blocked by anti-transforming growth factor beta antibodies. These studies suggest that cytokine secretion plays a role in the suppression of retrovirus transduction of human CD34+ cells.

3T3 Cells↗
PubMed1994

[Bridging long tibial shaft defects by partially demineralized bone matrix].

The problems arising from the transplantation of autogenic and allogenic bone have significantly limited the use of these methods. Hence, there is an ever increasing demand for suitable transplant materials that could be readily available to orthopaedic surgeons throughout the country. Although the advantages of demineralized bone matrix over allogenic cancellous bone have been shown in numerous experimental studies, its broad clinical application has so far been limited. The purpose of this study was to investigate the osteogenic properties of partially demineralized bone matrix in clinically relevant and realistic conditions. Tibial defects 5 cm in length in 24 merino sheep were bridged by way of medullary nailing and filled with various preparations of bone matrix. Cortical bone displaying poor vascularization and rotation instability of the osteosynthesis ensured extremely difficult testing conditions for the transplant. Postoperatively, the extent of new bone formation was evaluated by means of regular X-ray examinations over a period of 12-20 weeks. In addition, histological, fluorescent-optical and microradiographic examinations of the final specimen were carried out. Good new bone formation regularly followed the transplantation of partially demineralized bone matrix with a particle size of 750 microns. Complete bridging of the defect was achieved when small amounts of bone marrow were added. The use of bone matrix with a smaller or larger particle size did not influence the rate of new bone formation perceptibly.

Animals↗
PubMed1994

[Possibilities in the reconstruction of bone defects].

The importance of the functional unit "bone-soft-tissue" for the treatment of bone defects is discussed. A division is made between non-vascular and vascular bone transport. The individual methods are explained and their clinical significance is illustrated partly using case material. In general, the best way to fill small defects in vital soft tissue is to use cancellous autografts. For bridging longer bone defects callus distraction is the method of first choice, but in individual cases vascularized bone transfer can be taken from the iliac crest or the fibula. Homo- or heterografts should only be used in cases where no autologic bone material is available or when there is not enough.

Arm Injuries↗
PubMed1994

Correction of the enzyme deficiency in hematopoietic cells of Gaucher patients using a clinically acceptable retroviral supernatant transduction protocol.

Gaucher disease is a lysosomal storage disorder caused by a deficiency of the enzyme glucocerebrosidase (GC), and is an excellent candidate for gene replacement therapy. To develop a clinically acceptable protocol for this purpose, we created two amplified (A) high-titer retroviral vector-producer cell lines to efficiently transduce hematopoietic stem and progenitor cells. GP+envAm12/A-LGSN (A-LGSN), contained the GC cDNA driven by the retroviral long terminal repeat (LTR) and the neomycin phosphotransferase gene expressed from the simian virus 40 early promoter. GP+envAm12/A-LG4 (A-LG4) contained only the GC gene driven by the LTR. Both A-LGSN and A-LG4 contained multiple proviral copies and gave approximately 10-fold higher titers on 3T3 cells compared to their unamplified counterparts. These vectors were packaged in GP+envAm12 cells because vectors produced in this cell line transduced hematopoietic cells more efficiently than other packaging cells tested. Bone marrow mononuclear cells and purified CD34+ cells were infected with virus supernatants four times in the presence of interleukin-3 (IL-3), IL-6, and stem cell factor (SCF) over 96 hours in culture. Cells were then plated in semisolid cultures and colony-forming unit-granulocyte/macrophage (CFU-GM) colonies were scored for vector presence by polymerase chain reaction (PCR). Transduction efficiency of CFU-GM colonies derived from CD34+ cells was improved considerably using the amplified vectors in the GP+envAm12 packaging line. For A-LGSN, A-LG4, and unamplified LGSN, transduction efficiencies were 41, 42, and 25%, respectively. Therefore, multiple proviral copies resulting in higher titer improves retroviral transduction of human hematopoietic progenitor cells. Hematopoietic cells from Gaucher patients were transduced and placed into long-term bone marrow culture (LTBMC). Viral supernatant from the amplified producer lines transduced long-term culture initiating cells (LTCIC) efficiently (30 to 50%) using this clinically acceptable protocol. Both sustained mRNA expression and GC enzyme production are achieved in the long-term culture of LTCIC and lead to correction of the GC deficiency in their progeny cells.

Bone Marrow Cells↗
PubMed1993

Forgotten person in the Huntington disease family.

Although spouses play a major role in managing the care of persons affected with Huntington disease (HD), often at the price of subordinating their own aspirations and needs, little or no professional attention has been given to them in the HD literature. Such factors as secrets kept from the spouse, the early age-of-onset of symptoms, gender, and the coping strategies employed by spouses of affected persons are discussed and illustrated. Also, the impact of predictive testing for HD on spouses of persons undergoing testing is briefly touched on.

Adaptation, Psychological↗
PubMed1993

Hematopoietic origin of human natural killer (NK) cells: generation from immature progenitors.

Human natural killer (NK) cells originate from bone marrow, but little is known about NK cell progenitors and ontogeny. We studied the phenotype and functional activity of NK cells derived from highly purified human bone marrow CD34+ cells, which exhibited neither lytic activity nor expression of surface antigens characteristic of NK (CD56) or T (CD3) cells. However, when cultured with hematopoietic growth factors or feeder layers for up to 4 weeks, up to 86% functional CD56+ cells were seen in the absence of mature T cell development. CD56+ cells appeared in all cultures at 2 or 3 weeks, with the largest percentage in those exposed to IL-2. These studies demonstrated that NK cells arise 'in vitro' from immature bone marrow progenitors and also suggest a separate origin and differentiation pathway for NK and T cells.

Antigens, CD↗