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Biomedical subjects

F Hess

Publications and source records attributed to F Hess.

At least 55 records · Page 3Linked to original sources

[Effect of removal of serum from the culture medium and sublethal roentgen irradiation on microvilli and invaginations of the cell membrane of Ehrlich ascites tumor cells in monolayer cultures].

In order to find out modifications of microvilli and invaginations, the cellular surfaces of Ehrlich ascites tumor cells in monolayer culture (basal medium of Eagle + 10% fetal calf serum) were investigated with the aid of electron-microscopic cross-sections. The tumor cells had been cultured without serum 24 hours prior to investigation or irradiated with 2 Gy. Morphometric evaluation after cell culture in a serum-free medium showed a reduced number ob microvilli and a diminution of sections of microvilli. As already described before, a reduction of cell proliferation, of the microtubule-microfilament system, and of the endocytosis activity occurs under these serum-free conditions. The number of invaginations (related to a constant membrane part) was reduced by nearly 50% after serum extraction. Similarly to serum extraction, sublethal X-ray irradiation reduced the sections of microvilli, whereas the number of microvilli increased slightly. Contrary to the effect of serum extraction, the irradiated cells showed twice as many invaginations as the non-irradiated control cells. These differences in the surface structures are interpreted as a result of modified growth stimulations (+/- serum) and radiogenic reparation processes.

Animals↗

Evaluation of the patency rate of fibrous microvascular polyurethane prostheses after implantation in the rat aorta.

Two types of fibrous polyurethane prostheses with different compliances were implanted into the rat aorta with interrupted sutures and a running suture line. Excluding two technical failures, one unexplained death, and three infected prostheses, both groups (n = 21) showed a patency rate of 100%, up to 6 months after implantation. Rapid reendothelialisation occurred, and a stable neo-intima was formed. Compliance of the prostheses, as well as the suture technique used, has proven to be an unimportant factor in the rat aorta model, probably due to the low magnitude of the pulsations of the rat aorta. The experience of the surgeon with microsurgical techniques seems to be an underestimated factor in determining patency rates of microvascular prostheses.

Animals↗

Atraumatic panmural rupture of the esophagus: Boerhaave syndrome.

Three cases of spontaneous rupture of the distal esophagus are presented. All three patients presented in acute distress, exhibiting epigastric pain and signs of cardiovascular collapse. They all underwent surgery for repair of the lesion. One died postoperatively, and the other two patients recovered after a complicated postoperative period. Because Boerhaave syndrome has a high mortality rate and its diagnosis can be elusive, a high index of suspicion should be maintained by the attending physician.

Aged↗

Treatment of penis carcinoma.

Amputation of the penis is by no means the quickest and least invasive of the surgical methods of treating penis carcinoma. Radiation therapy has the advantage of preserving the integrity of the penis and does not render a later operation of the penis impossible. Regional lymph node metastases should be removed surgically whenever possible; their radical extirpation, especially total lymphadenectomy, should not be too vigorous because it is essential to avoid any complications, and irradiation of the inguinal and iliac lymph node regions by modern methods of radiation therapy is acceptable to the patient and can still be helpful even in more advanced cases. We do not yet have enough experience with cytotoxic therapy, bleomycin or laser coagulation to alter our present method of treatment.

Adult↗

[Radiotherapy of cervix and uterus carcinomas (Marburg results of 1960 to 1975)].

The authors present the therapy results and complications of 479 patients with carcinomas of the cervix and 241 patients with carcinomas of the body of the uterus. The five-year survival rate of the patients with carcinomas of the cervix is 57%. The first five years after diagnosis were survived by 79.6% of the patients in stage I, 57.3% of the patients in stage II, 31.1% of the patients in stage III, and 5.9% of the patients in stage IV. 60% of these patients were only submitted to percutaneous and intracavitary irradiation, and 40% were irradiated after operation. The five-year survival rate of the patients with carcinoma of the body was 74.3%. This rate was 80.8% in stage I, 77.5% in stage II, 57.5% in stage III, and 30% in stage IV. The operation frequency was relatively high with 74%, only 26% of these patients were only treated by radiotherapy. The percutaneous radiotherapy was performed exclusively under high voltage conditions, preponderantly according to the method of Marburg which allows a homogenous, small-field irradiation of the small pelvis with a dose until 45 Gy, but which deliberately does not expose to radiation the para-aortal lymph nodes. In the years of 1966 to 1971, a comparison with the method established in Düsseldorf was made. This method is working with two big U-shaped stationary fields including the para-aortal lymph nodes. The central part of the pelvis is collimated when percutaneous irradiation is applied, and the intracavitary treatment is applied with a higher dose, correspondingly. The present analysis of the treatment results of both methods does not show any significant difference as to the survival time. The incidence of fistulas, however, a severe late complication, which is 2.4% for the method of Marburg, is markedly lower than that of 8.6% for the other method. Prognostic factors and therapeutic aspects are discussed in detail.

Adult↗

[Ultrastructural studies on the effect of roentgen rays and quinacrine (atebrin)--alone or in combination--on Ehrlich ascites tumor cells in monolayer culture].

Already two days after an X-ray irradiation with 8 Gy performed during the phase of exponential growth, the cells of an Ehrlich ascitic carcinoma in monolayer culture showed remarkable ultrastructural modifications, e.g. a markedly vacuolized endoplasmic reticulum, swollen mitochondria, increase of lysosome-like structures, and a decrease of microvilli in number and size. Ehrlich ascitic carcinoma cells submitted to an X-ray irradiation with 8 Gy and subsequently incubated with quinacrine (Atebrin) in a concentration of 4 x 10(-6) M, which alone had no significant effects on growth or ultrastructure, showed severe cellular lesions. The endoplasmic reticulum was still more vacuolized, the mitochondria were severely damaged, lysosome-like structures and residual bodies were increased, and the cellular surfaces had still less microvilli. Microtubules and microfilaments, however, seemed rather increased. The effects of quinacrine (Atebrin) on cells exposed to X-rays were discussed with respect to the known inhibiting action of this substance on DNA synthesis, especially with regard to DNA reparation. The modifications of the microtubule-microfilament system could be correlated to increased intracellular digestive processes involved in the catabolism of radiodamaged structures.

Animals↗

[Influence of x-rays and quinacrine (atebrine) or chloroquine (resochine)--alone or in combination--on growth and melanin formation of Harding-Passey melanoma cells in monolayer culture].

Harding-Passey melanoma cells in monolayer culture (HPM-73 line) were treated during exponential growth phase with single doses of X-rays (85 kV) from 2 up to 16 Gy (200 to 1600 rd). While 2 or 4 Gy resulted in a growth retardation (up to 2 days) followed by resumption of proliferation thereafter, 8 Gy, and still more pronounced 16 Gy, resulted in a significant decrease of the survival rate (till about 5 to 10% after 8 Gy). In the course of several days after 8 or 16 Gy numerous large cells--in comparison with controls--were formed, and following exposure to 8 Gy the average cellular protein content had more than doubled (and after 16 Gy more than tripled) in the course of 11 days. The inhibitory effect of X-irradiation on cell multiplication was significantly augmented by continuous incubation in culture media containing either quinacrine (atebrine) or chloroquine (resochine) in concentrations (3-6 X 10(-6)M) which in itself were not or only little inhibitory. Especially noteworthy was the death of all cells in cultures irradiated with 8 Gy and incubated for several weeks with 6 X 10(-6)M quinacrine or chloroquine. Also, treatment with 6 X 10(-6)M chloroquine of cultures irradiated with 4 Gy resulted in death of all cells. The specific melanin content (E400/10(6) cells or E400/mg cell protein) of cultures significantly increased several days after X-ray irradiation. Also, treatment with chloroquine (but not with quinacrine) resulted in an increased melanin content which was most strikingly increased after the combined treatment of irradiation and chloroquine. The effects of quinacrine and chloroquine on pre-irradiated cells were discussed under the aspect of the well-known inhibitory action of these substances on DNA-synthesis, especially in connection with DNA repair processes.

Cell Survival↗

An ultrastructural study of developing stages of exo-erythrocytic Plasmodium berghei in rat hepatocytes.

The ultrastructure of immature exo-erythrocytic forms of Plasmodium berghei in rat hepatocytes was studied at stages between 25 and 51 h of development. A new method was successfully applied to localize the parasites in a small portion of the liver by temporary ligature of blood vessels to the majority of the liver, and from the spleen and the pancreas. Nuclear profiles appeared to be part of a highly lobed nuclear reticulum. Peripheral vesiculation and vacuolization of the cytoplasm was increasingly prominent and ushered in the formation of pseudocytomeres. Spacing between host- and parasite-derived membranes could first be observed after 43 h of development. In general, organellar development was found to follow closely that described for plasmodial oocysts.

Animals↗

[Action of x-rays and neuraminidase on pinocytotic activity and microtubule-microfilament system of Ehrlich ascites tumor cells in monolayer culture (author's transl)].

Monolayer cultures of Ehrlich ascites tumor cells in exponential growth phase were treated with X-rays and neuraminidase alone or in combination. A radiation dose of 2 Gy (200 rd) and higher effected a significant inhibition of DNA synthesis and cell proliferation. Neuraminidase treatment in addition to irradiation did not modify the growth-inhibitory irradiation effect. Cells pretreated for 0.5 to 1.0 hours with neuraminidase (in Earle's salt solution) and cultured thereafter (4h) in serum-containing growth medium exhibited an enhanced development of the microtubule-microfilament-system. Morphometric analysis of microtubules on electronmicroscopic sections revealed a nearly 4-fold increased number in neuraminidase treated cells while the average length of microtubules was similar to controls. Pinocytosis as measured by the ultrastructural uptake of ferritin appeared to be increased following neuraminidase treatment. A connection between neuraminic acid containing components (glycoproteins or glycolipids?) of the cell membrane or cell surface, on the one hand, and the cytoskeleton and the endocytotic process of these tumor cells, on the other hand, is suggested.

Animals↗

[Diagnostic value of clinical methods in the staging of abdominal Hodgkin's disease (author's transl)].

Explorative laparotomies were carried out on 68 patients with Hodgkin's disease in the University Hospital of Marburg from 1969 through 1978. These laparotomies were preceded by clinical examination, abdominal sonography in 27 cases, lymphography in 55 cases, scintigraphy of liver and spleen in 58 cases, and radiographic examinations of the intestinal tract in 18 cases. Sonography revealed a greater accuracy (90%) for splenic involvement than scintigraphy (74%); the results of sonography and scintigraphy of the liver were comparable. For the detection of para-aortal lymphomas ultrasound and lymphography can be regarded as complementary methods. Our results are compared with findings in the literature on abdominal sonography (n = 50), scintigraphy of liver and spleen (n = 185), and lymphography (n = 465) carried out before explorative laparotomy for lymphogranulomatosis. There was a better correlation for the systemic symptoms of the 68 patients with the clinical stage than with the pathologic stage. The importance of diagnosing different groups, e.g. in stage III, is stressed.

Abdominal Neoplasms↗

[Real-time B-scan ultrasonic evaluation of pleural effusion and intrathoracic masses adjacent to the pleura (author's transl)].

106 pleural effusions or pleural opacities suggesting fluid were evaluated in a prospective study by B-mode real-life sonography and radiography. 41 cases were first investigated by means of ultrasound, 65 by the conventional erect roentgenogram. The correct diagnosis of pleural fluid was made by ultrasound in 95.3% and by radiologic examination in 86.8% of the cases. Radiography failed to distinguish between pleural effusion and solid pleural thickening in 7.5%, sonography in 1.9% of the cases. In 8 patients with normal roentgenograms, small epidiaphragmal pleural effusions were detected by means of ultrasound. In diagnosis of pleural effusion, sonography was found to be superior to the conventional radiologic technique both in sensitivity and in diagnosing the consistency. The value of the ultrasonic method both in establishing the quality of intrathoracic masses adjacent to the pleura and in sonographically guided needle puncture is emphasized.

Diagnosis, Differential↗

Vidarabine: a preliminary review of its pharmacological properties and therapeutic use.

Vidarabine is the first drug to become generally available in the USA for parenteral treatment of life-threatening or debilitating herpes simplex virus infections of man. For the past decade laboratory and clinical studies have been in progress to assess the pharmacology of the compound, its mechanism of action and its potential usefulness in clinical investigations. Currently, clinical usefulness has been established for herpes simplex infections of the eye and brain. Further studies in progress are evaluating the drug's ability to prevent progressive disease from herpes zoster in the immunocompromised patient, reduce mortality and morbidity from neonatal herpes simplex virus infection and improve outcome of chronic hepatitis B infection.

Antiviral Agents↗

Splenic transposition with ligation of the vascular pedicle in rodents. Immunological consequences.

By splenic subcutaneous transposition and ligation of the vascular pedicle, the direct relation spleen-liver was interrupted in rodents infected with malaria. It was demonstrated that in this situation detoxification of the liver and recovery from malaria was evidently hampered by the lack of a direct splenic cell supply, due to retardation of the homing and differentiation in the spleen of precursors of immunologically competent cells. In the presence of blood-borne antigens and/or hepatotoxins, this simple 'shunt' operation appears to constitute a serious immunological handicap. However, it may be a useful model for the study of cellular and microenvironmental interrelationships of the immune response versus blood-borne antigens.

Animals↗

Survival of auxiliary rat liver grafts with decreased portal blood flow.

After auxiliary liver transplantation in the rat, partial liver grafts (30% of the liver) were perfused with mesentericosplenic venous blood. This means a decrease in the total liver blood flow by approximately 34%. Recipient livers retained their arterial and pancreaticoduodenal inflow. Surgical interventions were carried out on the recipient's liver to evaluate the effect of the varying induced functional handicap on the fate of the graft in association with a decreased liver blood flow. Graft survival was obtained in all groups, but the conditions of the graft varied inversely with the severity of the functional handicap of the recipient's liver. Compared to previous experiments in which the auxiliary grafts were supplied with total portal blood inflow in the same experimental model, the grafts in this study showed a slightly impaired increase in weight. This impairment was attributed to the decreased blood flow. Recipient livers deteriorated or just maintained their size, even after 70% hepatectomy, despite the pancreaticoduodenal venous and arterial inflow. These results suggest that the total liver blood flow in combination with the functional state of the remaining recipient liver, rather than the quality of venous blood deriving from certain splanchnic areas and/or peculiar factor convoyed with it, determines the survival of a liver graft.

Animals↗

[Influence of serum content of the culture medium upon growth and microtubule-microfilament system of Ehrlich ascites tumor cells in monolayer culture (author's transl)].

Withdrawal of serum from the medium of monolayer cultures of the Ehrlich ascites tumor within their phase of exponential growth resulted in a nearly complete inhibition of growth during a 25-hour incubation, but cells were not dying off. In the course of this serum-free incubation no significant alteration of the cellular glycolytic rate was seen. Addition of serum to cultures which previously had been incubated without serum led to a resumption of cell proliferation. The microtubule-microfilament system of cells cultivated without serum as compared to cells cultured in presence of serum was significantly reduced concerning the number and length of microtubules as well as the diffuse, bunchy or reticular arrangement of the microfilaments. The lesser development of the microtubule-microfilament system corresponds well to the reduced pinocytosis activity (ascertained by former studies) which is caused by a lack of serum. The present experiments altogether give support to the concept that serum factors as exogenous stimuli are necessary not only for cell growth but also for the probably closely interrelated development of the microtubule-microfilament system needed e.g. for the organization of cell surface structures and activities.

Animals↗