Biomedical subjects

K Natsis

Publications and source records attributed to K Natsis.

22 records · Page 2Linked to original sources

PubMed1996

Ultrastructural study of the urothelial lysosomal system in patients with transitional cell carcinoma after transurethral resection and interferon therapy.

The epithelial cells of human bladder urothelium contain a prominent lysosomal system on the surface layer which involves autophagic, phagocytotic and excretory processes. The noninvolved urothelium of tumor-bearing patients, however, does not contain this well-developed lysosomal system. Interferon restores the differentiation of the urothelium. Its action on the lysosomal system, however, has not been investigated. We studied ultrastructurally the noninvolved urothelium of eight patients with transitional cell carcinoma who after transurethral resection and intravesicular interferon instillations for 2 years did not develop recurrence. We noted that the number and size of lysosomes increased, being most numerous within the cells of the surface layer. Characteristic large lysosomes with the morphology of multivesicular bodies were also evident. These multivesicular bodies were almost entirely filled with small vesicles containing a dense core. Our findings show that after 2 years of interferon administration a re-appearance of a highly developed lysosomal system of the noninvolved urothelium was evident. This restoration to the normal morphology with reappearance of the lysosomal system, which could be partly attributed to interferon therapy, may be of clinical significance for prevention of tumor recurrence.

Aged↗

PubMedDate not supplied

Effect of navelbine on inhibition of tumor growth, cellular differentiation and estrogen receptor status on Lewis lung carcinoma.

We studied the antitumor activity of Navelbine (NVB) together with its ability to induce cellular differentiation and to influence estrogen receptor status of Lewis lung carcinoma (LLC). A total of 32 C(57)B1 mice divided into 5 groups were used for transplantation of LLC. Four groups of mice were treated with 5.0, 2.5 and 1.25 mg/kg/day from day 1 to 9 and 1.25 mg/kg on days 1, 7 and 13. Eight mice were controls. The dose of 1.25 mg/kg/day was the most effective and produced 72.7% inhibition of tumor growth. Ultrastructurally, on day 1 the cells showed poor differentiation. On day 14, in the case of 72.7% inhibition of tumor growth the study revealed a significant restoration of the morphology of the cells. Estrogen receptors gave a positive value in contrast to the initial measurement which was negative. The present study demonstrated good antitumor activity of NVB on LLC. NVB may also induce cellular differentiation and influence the estrogen receptor status.

Animals↗

PubMedDate not supplied

Orbital depth measurements of human skulls in relation to retrobulbar anesthesia.

To investigate the orbital depth in human skulls in relation to retrobulbar anesthesia, we measured the distance between the lateral margin of the optic foramen and the border of the medium and outer third of the inferior orbital rim (retrobulbar needle pathway) in 50 skulls (25 males and 25 females). This distance varied from 4.4 to 5.7 cm in males (mean 5.024, SD 0.272) and from 4.5 to 5.5 cm in females (mean 4.9, SD 0.204). There was no real difference between males and females (p>0.05). For the total of 50 skulls the mean distance was 4.962 cm (SD 0.246). Shallow and deep orbits exist in both males and females but individuals with shallow orbits are obviously more susceptible to optic nerve injury by the retrobulbar needle.

Anesthesia, Local↗

PubMedDate not supplied

The risk of optic nerve injury in retrobulbar anesthesia: a comparative study of 35 and 40 mm retrobulbar needles in 12 cadavers.

PURPOSE: This study was designed to demonstrate the increased risk of optic nerve injury by the 40 mm needle when fully inserted into the orbit. METHODS: Retrobulbar anesthesia needles 35 and 40 mm long were inserted into the orbits of 12 well-embalmed cadavers, as for typical retrobulbar anesthesia. The needle was seen directly through a fenestration of the orbital roof and by dissection of the orbital structures overlying the optic nerve. RESULTS: In all orbits the 40 mm needle reached and in seven cases significantly pushed against the optic nerve and could obviously penetrate its sheaths. The 35 mm needle could just slightly touch the outer optic nerve sheath only in two cases. CONCLUSIONS: We conclude that the 40 mm retrobulbar needle should not be fully inserted into the orbit and the 35 mm retrobulbar needle must be used with caution.

Anesthesia, Local↗