[The sonarographic diagnosis of prostatic and periprostatic cysts on high resolution transrectal ultrasound imaging]

The symptoms of prostatic and periprostatic cysts are nonspecific and digital rectal examination has no definite findings detected. The conventional radiological plain film cannot define the relationship of a cyst to the surrounding structures. The use of MRI as a means in detection is too expensive. To solve these problems, we detected 118 cysts in 73 patients by transrectal ultrasound (TRUS) and discussed the TRUS imaging findings of various prostate and periprostate cysts with illustrations from our clinical practice. We suggest that TRUS can be used routinely, because its distinct advantage of high resolution for minute nodular or cystic lesion detection with high quality image demonstrates the relationship of surrounding structures, and provides an outstanding novel diagnostic modality.

[Preparation of chitosan-gelatin mixed film and study on it's biodegradability]

A chitosan-gelatin film is prepared and the biodegradability and biocompatibility of the film are investigated by animal experiments. Results suggest that chitosan-gelatin film may be biodegraded faster and it has good biocompatibility. Lysozyme may promote biodegradation of the mixed film.

Attenuation of diabetes-associated mesenteric vascular hypertrophy with perindopril: morphological and molecular biological studies

Vascular disease is now the major cause of morbidity and mortality in the diabetic population. Our group explored the vascular changes associated with experimental diabetes and examined whether these changes can be ameliorated by angiotensin-converting enzyme (ACE) inhibition. The ACE inhibitor perindopril (PE) was administered to streptozotocin-induced diabetic rats for 24 weeks. At death, mesenteric vessels were perfused in vivo followed by assessment of the vascular architecture by quantitative histomorphometry. In a subgroup of animals, RNA was extracted from the mesenteric vasculature for assessment of gene expression of the prosclerotic cytokine, transforming growth factor beta 1 (TGFbeta1), and the matrix protein, type IV collagen. Diabetes was associated with smooth muscle hypertrophy and extracellular matrix (ECM) accumulation. ECM accumulation, particularly collagen deposition, was observed in the medial and adventitial layers. ACE inhibition prevented mesenteric vascular hypertrophy after 24 weeks of diabetes. In addition, overexpression of TGFbeta1 in the vessels of diabetic animals was prevented by PE treatment. Similarly, type IV collagen mRNA levels were increased in diabetic vessels, and this overexpression was also prevented by PE therapy. In summary, ACE inhibition attenuates many of the vascular changes observed in experimental diabetes and may have important clinical implications as a vasoprotective agent in human diabetes.

[The changes and significance of the intensity of transcription of endothelial nitric oxide synthase-mRNA in placental tissue from cases of pregnancy induced hypertension]

OBJECTIVE

To determine the cause of decreasd expression of endothelial nitric oxide synthase (eNOS) in placental tissue from cases of pregnancy induced hypertension (PIH).

METHODS

9 placentae of normal pregnant women and 12 placentae of patients with PIH were studied. eNOS-mRNA was measured in placental tissue by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

(1) There was eNOS-mRNA in placental tissue of normal pregnancy as well as PIH cases. (2). The intensity of transcription of eNOS-mRNA in placental tissue of PIH cases decreased significantly when compared with that of normal pregnancy (P < 0.05).

CONCLUSION

The decrease of the intensity of transcription of eNOS-mRNA in placental tissue of PIH patients may result in reduction of expression of eNOS in placental tissue of PIH.

[Pulmonary lymphangitic carcinomatosis]

OBJECTIVE

To explore the clinical manifestations of pulmonary lymphangitic carcinomatosis (PLC), to analyse its associated diagnostic methods, and to improve the understanding of PLC and its diagnosis.

METHOD

Retrospective analysis of 4 cases of PLC and review of the literature.

RESULT

The clinical manifestations of PLC include: (1) dyspnea and cough; (2) normal or restrictive pattern ventilation; (3) diffuse or local reticulonodular infiltrates in the lung like interstitial fibrosis and pleural effusion on chest radiograph; (4) CT and high-resolution CT (HRCT) scans reveal a beaded chain appearance caused by uneven thickening of the interlobular septa and pleural membrane, polygonal thickening of bronchovascular bundles, and mediastinal lymphadenopathy as well.

CONCLUSION

These clinical data suggest that any manifestations similar to pulmonary interstitial fibrosis complicated with pleural effusion and paratracheal lymphadenopathy should be further differentiated from PLC by HRCT and pleural-lung tissue biopsy.

Identification of a domain on the integrin alpha5 subunit implicated in cell spreading and signaling

The alpha5 beta1 integrin is a cell surface receptor for fibronectin implicated in several cellular activities including cell proliferation, differentiation, and migration. The primary site at which the alpha5 beta1 integrin interacts with fibronectin is the RGD (Arg-Gly-Asp) amino acid sequence. In general, the sites on the integrin alpha subunits involved in ligand binding are not well characterized. Based on previous cross-linking studies, sequence alignment, predicted conformation, and intron-exon boundaries, we identified a 144-residue region (positions 223-367) on the alpha5 subunit as a putative binding region and divided it into four subdomains named domains I, II, III, and IV. Chimeric receptors were prepared in which sequences on the alpha5 subunit were exchanged with the corresponding sequences on the alpha6 subunit, which is specific for laminin and does not bind via an RGD sequence. The mutated human alpha5 integrin gene was transfected into CHO B2 cells, which are deficient in alpha5 expression. Only chimeras of domain III or IV express on the cell surface. Both of these chimeras decreased the adhesion, spreading, focal adhesion assembly, and migration on fibronectin. The adhesion of the chimeric receptors to fibronectin remained sensitive to the RGD peptide, and antibodies that inhibit interaction with the fibronectin synergy site and RGD loop remain inhibitory for the chimeras, indicating that our chimeras do not inhibit binding to either the RGD or synergy sites. Finally, the affinity of soluble fibronectin to cells via the alpha5 beta1 receptor decreased only about 3-fold. This decrease is substantially less than the observed effects on migration and spreading, which were not altered by changes in substrate concentration. Thus, the alteration in binding sites does not easily account for the changes in cell spreading and focal adhesion assembly. The tyrosine phosphorylation and focal adhesion assembly that are seen when cells expressing the wild type alpha5 receptor adhere to fibronectin were inhibited in cells expressing the chimeric receptors. Therefore, our results suggest that the chimeras of these domains likely interrupt alpha5-mediated conformational signaling.

[Studies on the chemical constituents of Smilax glabra]

Smilax glabra is a well-known traditional Chinese medicine which has been used clinically to prevent leptospirosis, to treat syphilis, and acute bacterial dysentery, etc. Its extracts showed anti-tumor and anti-atherosclerosis activity. A new isoflavone, 7,6'-dihydroxy 3'-methoxy isoflavone (1), along with two known compounds taxifolin (2) and astilbin (3), have been isolated from the roots of Smilax glabra. The structures were elucidated by spectroscopic methods including 2DNMR techniques.

Lipofection indirectly increases expression of endogenous major histocompatibility complex class I molecules on tumor cells

Direct intratumoral injection of a lipid/DNA complex encoding an allogeneic major histocompatibility complex (MHC) class I molecule leads to regression of both an immunogenic murine tumor and also melanoma lesions in some patients. We have sought to understand the mechanism(s) for this augmentation of antitumor activity. While optimizing parameters for in vitro gene transfer into the D5 subclone of B16BL6, it was noted that lipofected tumors not only expressed the new alloantigen but also exhibited increased expression of endogenous MHC class I, both H-2 Kb and H-2 Db. This increase in expression was not restricted to the small percentage of cells that expressed the transfected gene, but appeared to affect the majority of cells in culture. Class I expression was not increased by lipopolysaccharide, DNA alone, lipid, or lipid/lipopolysaccharide mixtures. Enhanced class I expression required a DNA/lipid complex and was greatest when parameters optimized for gene transfer of the alloantigen were used. All DNA plasmids tested had this effect, including one plasmid whose DNA was not transcribed because it lacked an expression cassette. Because of the critical role that MHC class I antigens play in immune recognition, we propose that lipid complex-mediated gene transfer may provide immunological advantages beyond those that are attributable to expression of the specific gene transferred.

Effects of the attenuation map used in the Chang algorithm on quantitative SPECT results

OBJECTIVE

This study examined the effects on SPECT quantitation caused by erroneous size and position of the attenuation map and inaccurate pixel size used in the Chang algorithm.

METHODS

Projection data of a three-dimensional head phantom were simulated with a uniform attenuation coefficient of 0.15/cm for the inside of the phantom. Images were reconstructed using the filtered backprojection algorithm without attenuation compensation and the Chang algorithm with different attenuation maps. Quantitative comparison then was performed between the reconstructed images and the phantom.

RESULTS

The pixel values obtained for noisy data by using the first-order Chang algorithm with an accurate attenuation map were less than 10% different from the true values and the left-right asymmetry was under 5%. Small errors in the geometric parameters of the attenuation map, however, caused considerable quantitative inaccuracy in the reconstructed image. For example, a 0.64-cm error in the size of the map caused 10% deviation from the true value and a 0.64-cm shift of the position of the map towards the left produced 10% left-right pixel value asymmetry.

CONCLUSION

The accuracy of the Chang algorithm critically depends on the geometric parameters. For a uniform attenuator with symmetric geometry, such as the human brain, a true left-right symmetry in the pixel value can be altered significantly by a small error in the geometric parameters, while symmetry can be maintained with no attenuation compensation.

Binding of Acanthamoeba to [corrected] mannose-glycoproteins of corneal epithelium: effect of injury

PURPOSE

Acanthamoeba keratitis is a sight-threatening corneal infection. It is known that: (i) more amoebae bind to the surface of injured corneas than to the normal corneal surface and (ii) mannose-containing glycoproteins (GPs) possess binding sites for Acanthamoeba. The present study was undertaken to determine whether subtle corneal surface injury exposes mannose-GPs and whether more amoebae bind to the mannose-GPs of injured corneas than to those of normal corneas.

METHODS

Corneal cup assays were developed to determine whether corneal surface injury exposes binding sites for a mannose/glucose-specific lectin, succinylated-concanavalin A (s-ConA). To determine whether injury exposes mannose-GPs, corneal surface proteins were biotinylated, biotin-labeled mannose-GPs were allowed to bind to s-ConA-agarose beads and were analyzed by SDS-polyacrylamide gel electrophoresis (PAGE). Amoeba binding to mannose-GPs of corneal epithelia was analyzed by PAGE-blot overlay assays.

RESULTS

S-ConA binding site density was 2.4 times greater on the injured corneal surface than on the surface of normal corneas. Based on the analysis of the s-ConA-bound, biotin-labeled corneal surface proteins, approximately 5.2 times greater amounts of mannose-GPs were present on the surface of injured corneas than on the normal corneal surface. PAGE-blot overlay assays of s-ConA bound GPs of unlabeled corneal epithelia revealed that, on a per mg total cell protein basis, injured corneal epithelium contained 1.8 times greater amounts of Acanthamoeba-reactive mannose-GPs than normal corneal epithelium.

CONCLUSIONS

Subtle corneal injury exposes mannose-GPs on the surface of injured corneas. The newly exposed GPs may serve to provide additional attachment sites for the amoebae. This, in turn, could render the cornea susceptible to the infection.

Structural and functional characterization of Streptomyces plicatus beta-N-acetylhexosaminidase by comparative molecular modeling and site-directed mutagenesis

We have sequenced the Streptomyces plicatus beta-N-acetylhexosaminidase (SpHex) gene and identified the encoded protein as a member of family 20 glycosyl hydrolases. This family includes human beta-N-acetylhexosaminidases whose deficiency results in various forms of GM2 gangliosidosis. Based upon the x-ray structure of Serratia marcescens chitobiase (SmChb), we generated a three-dimensional model of SpHex by comparative molecular modeling. The overall structure of the enzyme is very similar to homology modeling-derived structures of human beta-N-acetylhexosaminidases, with differences being confined mainly to loop regions. From previous studies of the human enzymes, sequence alignments of family 20 enzymes, and analysis of the SmChb x-ray structure, we selected and mutated putative SpHex active site residues. Arg162 --> His mutation increased Km 40-fold and reduced Vmax 5-fold, providing the first biochemical evidence for this conserved Arg residue (Arg178 in human beta-N-acetylhexosaminidase A (HexA) and Arg349 in SmChb) as a substrate-binding residue in a family 20 enzyme, a finding consistent with our three-dimensional model of SpHex. Glu314 --> Gln reduced Vmax 296-fold, reduced Km 7-fold, and altered the pH profile, consistent with it being the catalytic acid residue as suggested by our model and other studies. Asp246 --> Asn reduced Vmax 2-fold and increased Km only 1.2-fold, suggesting that Asp246 may play a lesser role in the catalytic mechanism of this enzyme. Taken together with the x-ray structure of SmChb, these studies suggest a common catalytic mechanism for family 20 glycosyl hydrolases.

Antitumour activity of the novel immune modulator 5,6-dimethylxanthenone-4-acetic acid (DMXAA) in mice lacking the interferon-gamma receptor

5,6-Dimethylxanthenone-4-acetic acid (DMXAA), a novel antitumour agent currently undergoing clinical evaluation, appears to mediate its antitumour effects through immune modulation and the production of cytokines. We used mice with a targeted disruption of the interferon-gamma (IFN-gamma) receptor gene as a model to evaluate the role of the host response to IFN-gamma in the antitumour action of DMXAA on colon 38 tumours. A feature of the results was that while DMXAA treatment induced both IFN-gamma and tumour necrosis factor (TNF) in serum, the increase was > 20-fold higher in IFN-gamma R0/0 mice than in wild-type mice. In contrast, mRNA levels for IFN-gamma and TNF were similar in the two mouse strains, suggesting that the concentrations of these cytokines were controlled by a post-transcriptional mechanism. Serum nitrate levels, used as a measure of nitric oxide production, were increased by DMXAA, but to a similar extent in both strains of mice. Complete regressions of colon 38 tumours were obtained in response to DMXAA in the knockout mice, although the dose required for 100% cure was higher and the reduction in tumour volume occurred more slowly than in the wild-type counterparts. The results demonstrate that the host response to IFN-gamma is not essential for an anti-tumour response. Similar results were obtained in mice that were immunosuppressed by treatment with cyclosporin A before treatment with DMXAA. The results are consistent with the concept that the antitumour activity of DMXAA involves complex immunomodulation, probably with significant redundancy in contributing cytokines.

Role of carbohydrate-mediated adherence in cytopathogenic mechanisms of Acanthamoeba

Acanthamoeba keratitis is a vision-threatening corneal infection. The mannose-binding protein of Acanthamoeba is thought to mediate adhesion of parasites to host cells. We characterized the amoeba lectin with respect to its carbohydrate binding properties and the role in amoeba-induced cytopathic effect (CPE). Sugar inhibition assays revealed that the amoeba lectin has the highest affinity for alpha-Man and Man(alpha1-3)Man units. In vitro cytopathic assays indicated that mannose-based saccharides which inhibit amoeba adhesion to corneal epithelial cells were also potent inhibitors of amoeba-induced CPE. Another major finding was that N-acetyl-D-glucosamine (GlcNAc) which does not inhibit adhesion of amoeba to host cells is also an inhibitor of amoeba-induced CPE. The Acanthamoebae are thought to produce CPE by secreting cytotoxic proteinases. By zymography, one metalloproteinase and three serine proteinases were detected in the conditioned media obtained after incubating amoebae with the host cells. The addition of free alpha-Man and GlcNAc to the co-culture media inhibited the secretion of the metalloproteinase and serine proteinases, respectively. In summary, we have shown that the lectin-mediated adhesion of the Acanthamoeba to host cells is a prerequisite for the amoeba-induced cytolysis of target cells and have implicated a contact-dependent metalloproteinase in the cytopathogenic mechanisms of Acanthamoeba.

[Biodegradation and biocompatibility of a chitosan film]

The biodegradability and biocompatibility of a chitosan film were investigated in mice. The results showed that chitosan films had a mild inflammatory reaction in the early days of grafting, and after 16 weeks the inflammation basically subsided. Chitosan films were easily biodegraded. Chitosan is a novel natural absorbable medical film material and has a good developmental prospect.

[Effects of mifepristone on ICE expression and Fas expression in early pregnant chorionic villi]

This study addressed the question whether mifepristone has any effect on apoptosis in early pregnant chorionic villi. Interleukin 1 beta converting enzyme(ICE) expression and Fas expression in early pregnant villi and their changes following mifepristone administration were detected by immunohistochmical method and computer image analysis. During early pregnancy, ICE and Fas were expressed in all component chorionic cells, predominantly syncytiotrophoblasts. ICE stained cytoplasma. Fas stained mainly cytoplasma, and in partial trophoblastic cells, Fas was expressed on membrane and nucleus. In the villi from the pregnant women who received mifepristone for 2 days, expression of Fas increased markely; the ratio of positive nuclear staining cells were significantly raised, but the immunostaining intensity of ICE was slightly increased. These results suggest that mifepristone may terminate early pregnancy via increasing the expression of Fas and promoting apoptosis in the chorionic villi.

Angiotensin converting enzyme inhibition and calcium antagonism attenuate streptozotocin-diabetes-associated mesenteric vascular hypertrophy independently of their hypotensive action

OBJECTIVES

To investigate the relative roles of angiotensin II, bradykinin, and calcium-dependent pathways in the genesis of mesenteric vascular hypertrophy in experimental diabetes.

DESIGN

Streptozotocin-induced diabetic Sprague-Dawley rats were randomly allocated to these treatments for 24 weeks: no treatment; ramipril at a hypotensive dose; ramipril plus the bradykinin type 2 receptor blocker icatibant; icatibant alone; ramipril at a low dose; the angiotensin II type 1 receptor antagonist, valsartan; the dihydropyridine calcium antagonist, lacidipine; and the nondihydropyridine calcium antagonist mibefradil.

METHODS

Systolic blood pressure was serially measured every 4 weeks by tail-cuff plethysmography. We assessed the vascular architecture in sections of mesenteric arteries obtained after in-vivo perfusion, which were stained with an antibody to alpha-smooth muscle actin.

RESULTS

Both blood pressure and the mesenteric arterial wall: lumen ratio were reduced by administration of ramipril, at the high dose, either alone or in combination with icatibant, and also by valsartan. Treatment either with the low dose of ramipril or with the calcium antagonists lacidipine and mibefradil was associated with a decrease in the wall : lumen ratio of the mesenteric arteries without influencing blood pressure.

CONCLUSIONS

These findings demonstrate that blockade both of angiotensin II-dependent and of calcium-dependent pathways attenuates mesenteric vascular hypertrophy in experimental diabetes. Furthermore, the antitrophic effects of these antihypertensive agents may be independent of their hypotensive effects.

Characterization of HetR protein turnover in Anabaena sp. PCC 7120

The hetR gene plays an important role in heterocyst development and pattern formation in heterocystous cyanobacteria. The hetR gene from Anabaena sp. PCC 7120 was overexpressed in Escherichia coli. Antibodies raised against the recombinant HetR protein (rHetR) were used to characterize metabolism of the HetR of Anabaena sp. PCC 7120 in vivo. HetR was present at a low level when Anabaena sp. PCC 7120 was grown in the presence of combined nitrogen. Shifting from nitrogen repletion conditions to nitrogen depletion conditions led to a two fold increase of HetR in total cell extracts, and most of HetR was located in heterocysts. The amount of HetR in total cellular extracts increased rapidly after shifting to nitrogen depletion conditions and reached a maximum level 3 h after the shift. Isoelectrofocusing electrophoresis revealed that the native HetR had a more acidic isoelectric point than did rHetR. After combined nitrogen was added to the nitrogen-depleted cultures, the degradation of HetR depended on culture conditions: before heterocysts were fully developed, HetR was rapidly degraded; after heterocysts were fully developed, HetR was degraded much more slowly. The distribution of HetR in other species of cyanobacteria was also studied.

[Effects of mifepristone on proliferation and apoptosis in early chorionic villi]

OBJECTIVE

To study the effects of mifepristone on proliferation and apoptosis in early pregnant chorionic villi.

METHODS

Proliferation and apoptosis in early pregnant choionic villi from surgical aspiration and mifepristone induced abortion were studied. Marker for proliferation is proliferating cell nuclear antigen (PCNA) immunohistochemical staining, apoptotic cell death was detected using DNA in situ terminal deoxynucleotidyl transferas-mediated dUTP-biotin nick ending labeling (TUNEL).

RESULTS

In early pregnant chorionic villi, proliferating index of cytotrophoblasts was 53.74% +/- 1.34%, not only nuclear but also cytoplasma were PCNA positive staining, syncytiotrophoblasts were negative. There existed apoptotic cell death in trophoblasts, the apoptotic index were 2.52% +/- 0.86% in syncytiotrophoblasts and 0.52% +/- 0.26% in cytotrophblasts, respectively. After 2 days mifepristone treatment, the proliferating index of cytotrophoblasts decreased slightly and PCNA positive cytoplasmic expression disappeared; while apoptotic cell increased significantly, the apoptotic indices were 22.16% +/- 2.26% in syncytiotrophoblasts and 20.12% +/- 1.74% in cytotrophoblasts, respectively.

CONCLUSION

Mifepristone may inhibit proliferation and promote apoptosis of trophoblasts in early pregnant chorionic villi.

NF-kappaB-inducing kinase activates IKK-alpha by phosphorylation of Ser-176

Activation of the transcription factor NF-kappaB by inflammatory cytokines involves the successive action of NF-kappaB-inducing kinase (NIK) and two IkappaB kinases, IKK-alpha and IKK-beta. Here we show that NIK preferentially phosphorylates IKK-alpha over IKK-beta, leading to the activation of IKK-alpha kinase activity. This phosphorylation of IKK-alpha occurs specifically on Ser-176 in the activation loop between kinase subdomains VII and VIII. A mutant form of IKK-alpha containing alanine at residue 176 cannot be phosphorylated or activated by NIK and acts as a dominant negative inhibitor of interleukin 1- and tumor necrosis factor-induced NF-kappaB activation. Conversely, a mutant form of IKK-alpha containing glutamic acid at residue 176 is constitutively active. Thus, the phosphorylation of IKK-alpha on Ser-176 by NIK may be required for cytokine-mediated NF-kappaB activation.

[Molecular cloning of a novel human lung cancer-associated antigen cDNA]

OBJECTIVE

To clone the gene of human lung cancer-associated antigen.

METHODS

The human lung squamous carcinoma cell line L-78 cDNA expression library was constructed with lambda gt 11 Sfi-Not directional cloning vector and screened with the anti-human lung cancer McAb ALT-04. The cDNA clone named hlc-14 was sequenced and further studied. NIH3T3 cells were transfected with the recombinant pXJ41-hlc14 plasmid, and the expression of hlc-14 cDNA was detected and characterized immunohistochemically. Soft agar colony formation assay of the transfectants was performed.

RESULTS

A human lung cancer lambda gt 11 cDNA library of 1.4 x 10(6) pfu/ml was constructed. Six cDNA clones were isolated following 4 rounds of immunoscreening. The largest cDNA clone hlc-14 contained 954 bp with no homology to any known gene when screened through GenBank. In the NIH3T3 cells transfectant of hlc-14 cDNA, the expression of the lung cancer-associated antigen was demonstrated. The ability of colony formation of the transfectant in the soft agar was enhanced.

CONCLUSION

The hlc-14 clone is a novel human lung cancer-associated antigen cDNA. It provides clues for the study of carcinogenesis mechanism of lung cancer and a novel target gene for the gene therapy of lung cancer.

[Cerebrospinal aporrhinosis of nasal sinus operation]

OBJECTIVE

To study the treatment of cerebrospinal aporrhinosis after nasal sinus operation, especially frontal, ethmoid tumor resection.

METHODS

Fourteen cases of cerebrospinal aporrhinosis after nasal sinus operations were reported.

RESULTS

Seven cases of cerebrospinal apporrhinosis were found during the operation. Two cases were repaired with tensor facia latae, 3 with mucosoperichondrium of nasal septum and EC otocerebral glue and 1 with TJ bone cement. Seven cases cerebrospinal aporrhinosis were found after the operations when intranasal packing was removed. They were cured by cerebral decompression and antibiotics, none complicated with intracranial infection.

CONCLUSION

Careful examination should be taken daring the operation. If aporrhinosis was found, it should be repaired immediately.

[Transglottic carcinoma and transglottic invasion of laryngeal carcinoma]

OBJECTIVE

To explore the definition of transglottic carcinoma and its pathological characteristics of local invasion, and to determine the distinction between transglottic carcinoma and transglottic invasion of laryngeal carcinoma.

METHODS

Fifty total laryngectomy specimens of transglottic carcinoma were subject to whole-organ serial section, HE staining and microscopic observation.

RESULTS

The ventricles of 50 cases were all invaded, the main lesion of carcinoma was in the ventricle, or the ventricle was the center of the lesion. The rate of invasion to paraglottic space(PGS) was 82%(41/50). Submucosal invasion was seen in 52%(26/50) and that with superficial mucosal invasion was seen in 38%(19/50). Superficial mucosal invasion rate was 10%(5/50). Deep submucosal invasion was the major way of tumor spread in transglottic carcinoma which equally involved the supraglottic and glottic regions.

CONCLUSION

Transglottic carcinoma originates from the center of ventricle where it spreads to transglottic region. Submucosal extension is characteristic of local invasion. There are fundamental differences between transglottic carcinoma and transglottic invasion of laryngeal carcinoma in the late stage of the lesion.

Alkyl esters of camptothecin and 9-nitrocamptothecin: synthesis, in vitro pharmacokinetics, toxicity, and antitumor activity

Eleven camptothecin esters, 6a-e and 7a-f, were prepared by straightforward acylation of camptothecins with the corresponding acylating reagents such as organic anhydrides and carboxylic acid chlorides. The in vitro pharmacokinetic determination of lactone levels of esters 6a and 7b showed that the biological life span of their lactone forms in human and mouse plasma significantly increased when compared with their mother compounds, camptothecin (3) and 9-nitrocamptothecin (4). The differences of lactone levels between human plasma and mouse plasma for 6a and 7b were much smaller than what was observed for their mother compounds. The in vivo antitumor activity and toxicity studies demonstrated that some of these esters were very active against human tumor xenografts in nude mice and had an exceptional lack of toxicity in nude mice, even at enormous doses.