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Biomedical subjects

T J Li

Publications and source records attributed to T J Li.

At least 19 recordsLinked to original sources
PubMed2026

Surgical Management of Young Women with High-Risk Breast Cancer Receiving Neoadjuvant Systemic Therapy on the I-SPY2 Trial.

BACKGROUND: Mastectomy rates in women with breast cancer are higher in younger women than in older women. The impact of this more extensive surgery on overall survival (OS) and locoregional recurrence in younger women is unknown, especially after neoadjuvant systemic therapy (NST). This study evaluated surgical management and outcomes of patients aged &#x2264; 45 versus > 45 years enrolled in multicenter NST clinical trial, I-SPY2.0 (NCT01042379, PMID 37325931). METHODS: We conducted a secondary data analysis comparing locoregional treatment in patients aged &#x2264; 45 versus > 45 years with clinical or molecular high-risk clinical stage II-III breast cancer treated from April 2010 to June 2022. Multivariate Cox proportional hazards models were used to evaluate associations between type of breast surgery with OS and locoregional recurrence-free interval by age group and tumor receptor subtype. RESULTS: Of 1737 patients, 698 (40.2%) were aged &#x2264; 45 years. There were no significant differences in patient or tumor characteristics or residual cancer burden distribution between age groups. Although breast-conserving surgery was significantly less common in younger women (36.8% vs 48.5%, p < 0.001), surgery type was not associated with OS or locoregional recurrence-free interval for patients aged &#x2264; 45 years. CONCLUSIONS: Greater extent of breast surgery was not associated with improved outcomes in women aged &#x2264; 45 years. Choice of surgical procedure in the management of breast cancer is multifactorial, but young age alone&#xa0;does not warrant mastectomy following NST.

Breast cancer↗
PubMed2006

Aqueous shunts for glaucoma.

BACKGROUND: Aqueous shunts are employed for intraocular pressure (IOP) control in primary and secondary glaucomas that fail medical, laser, and other surgical therapies. OBJECTIVES: This review compares aqueous shunts for IOP control and safety. SEARCH STRATEGY: We searched CENTRAL, MEDLINE, PubMed, EMBASE, NRR all in January 2006, LILACS to February 2004 and reference lists of included trials. SELECTION CRITERIA: We included all randomized and quasi-randomized trials in which one arm of the study involved shunts. DATA COLLECTION AND ANALYSIS: Two authors independently extracted data for included studies and a third adjudicated discrepancies. We contacted investigators for missing information. We used fixed-effect models and summarized continuous outcomes using mean differences. MAIN RESULTS: We included fifteen trials with a total of 1153 participants with mixed diagnoses. Five studies reported details sufficient to verify the method of randomization but only two had adequate allocation concealment. Data collection and follow-up times were variable.Meta-analysis of two trials comparing Ahmed implant with trabeculectomy found trabeculectomy resulted in lower mean IOPs 11 to 13 months later (mean difference 3.81 mm Hg, 95% CI 1.94 to 5.69 mm Hg). Meta-analysis of two trials comparing double-plate Molteno implant with the Schocket shunt was not done due to substantial heterogeneity. One study comparing ridged with standard double-plate Molteno implants found no clinically significant differences in outcome. Two trials investigating the effectiveness of adjunctive mitomycin (MMC) with the Molteno and Ahmed implants found no evidence of benefit with MMC. Two trials that investigated surgical technique variations with the Ahmed found no benefit with partial tube ligation or excision of Tenon's capsule. One study concluded there were outcome advantages with a double versus a single-plate Molteno implant and one trial comparing the 350 mm(2) and 500 mm(2) Baerveldt shunts found no clinically significant advantage of the larger device but neither of these trials included all patients randomized. One study suggested improved clinical outcome when MMC was employed with a newly described shunt including ultrasound supporting the conclusion. One small study did not demonstrate an outcome advantage to systemic steroid use postoperatively with single-plate Molteno shunts. One study comparing endocyclophotocoagulation (ECP) with Ahmed implant in complicated glaucomas found no evidence of better IOP control with Ahmed implant over ECP. AUTHORS' CONCLUSIONS: Relatively few randomized trials have been published on aqueous shunts and methodology and data quality among them is poor. To date there is no evidence of superiority of one shunt over another.

Cataract Extraction↗
PubMed2005

Direct comparison of dietary portfolio vs statin on C-reactive protein.

BACKGROUND: 3-Hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) markedly reduce serum cholesterol and have anti-inflammatory effects. The effect of cholesterol-lowering diets on inflammatory biomarkers is less well known. OBJECTIVE: To compare the efficacy of a dietary combination (portfolio) of cholesterol-lowering foods vs a statin in reducing C-reactive protein (CRP) as a biomarker of inflammation linked to increased cardiovascular disease risk. METHODS: In all, 34 hyperlipidemic subjects completed three 1-month treatments as outpatients in random order: a very low-saturated fat diet (control); the same diet with 20 mg lovastatin (statin); and a diet high in plant sterols (1.0 g/1000 kcal), soy protein (21.4 g/1000 kcal), viscous fibers (9.8 g/1000 kcal), and almonds (14 g/1000 kcal) (portfolio). Fasting blood samples were obtained at weeks 0, 2, and 4. RESULTS: Using the complete data, no treatment reduced serum CRP. However, when subjects with CRP levels above the 75th percentile for previously reported studies (> 3.5 mg/l) were excluded, CRP was reduced similarly on both statin, -16.3 +/- 6.7% (n = 23, P = 0.013) and dietary portfolio, -23.8 +/- 6.9% (n = 25, P = 0.001) but not the control, 15.3 +/- 13.6% (n = 28, P = 0.907). The percentage CRP change from baseline on the portfolio treatment (n = 25) was greater than the control (n = 28, P = 0.004) but similar to statin treatment (n = 23, P = 0.349). Both statin and portfolio treatments were similar in reducing CRP and numerically more effective than control but only the change in portfolio was significant after the Bonferroni adjustment. CONCLUSIONS: A combination of cholesterol-lowering foods reduced C-reactive protein to a similar extent as the starting dose of a first-generation statin.

Adult↗
PubMed2005

Effect of dietary oligochitosan supplementation on ileal digestibility of nutrients and performance in broilers.

The effect of dietary chitosan oligosaccharides (COS) supplementation on ileal digestibilities of nutrients and performance in broilers was assessed by feeding graded levels (0, 50, 100, 150 mg/kg) of COS. Two thousand four hundred male commercial Avian broilers (1-d-old) were assigned randomly to 5 dietary treatment groups (60 birds per pen with 8 pens per treatment). Diet A was a typical corn- and soybean meal-based diet supplemented with 6 mg/kg of an antibiotic flavomycin (positive control). Diet B was the basal diet without any supplement. Diets C, D, and E were formulated by adding 50, 100, and 150 mg/kg of COS to the basal diet, respectively. On the morning of d 21 and 42, 64 birds (8 per pen with 8 pens per treatment) from the growth trial for each age group were killed by cervical dislocation for determination of the ileal digestibilities of nutrients. Dietary supplementation with COS and antibiotic enhanced (P < 0.05) the ileal digestibilities of DM, Ca, P, CP, and all amino acids (except for alanine in the 21-d-old birds or phenylalanine, glutamate, and glycine for the 42-d-old birds). Feed efficiency was improved (P < 0.05) in response to dietary supplementation of an antibiotic or COS (150 mg/kg for d 1 to 21, and 100 and 150 mg/kg for d 21 to 42). The results demonstrate for the first time to our knowledge that dietary COS supplementation was effective in increasing the ileal digestibilities of nutrients and feed efficiency in broilers. Our findings may explain a beneficial effect of COS on chicken growth performance.

Animal Nutritional Physiological Phenomena↗
PubMed2002

Evaluation of mobile nylon bag technique for determining apparent ileal digestibilities of protein and amino acids in growing pigs.

The mobile nylon bag technique (MNBT) may offer a simple, rapid means for assessing ileal AA digestibility of pig feed ingredients. In the present study, the effects of washing bags recovered from digesta, the amount and fineness of feeds, and feed trypsin inhibitor activity on apparent ileal digestibilities (AID) of CP and AA were determined with the MNBT. Twenty-four ileorectal anastomosed pigs (Yorkshire x Chinese Black barrows, 30 kg initial BW), of which 12 were fitted with duodenal T-cannulas, were used. Not washing the bags recovered from ileal digesta resulted in a reduction (P < 0.05) in apparent ileal digestibilities of CP and AA determined by MNBT. Washing the bags for more than 4 min overestimated (P < 0.05) the apparent ileal digestibilities of CP and AA compared with those determined with the anastomosed pigs. Sample size and fineness of grinding also affected (P < 0.05) apparent ileal digestibilities of CP determined by MNBT. The apparent ileal digestibilities of CP determined by MNBT were reduced (P < 0.05) when sample size exceeded 0.75 g and when feed was ground through screens with a mesh size of more than 1.0 mm. The closest agreement between results obtained by MNBT and a conventional ileal digestibility assay occurred when 0.75 g of feed ground through a 1.0-mm mesh screen was used per bag and bags were washed for 2 min after retrieval from digesta. Further studies are warranted to investigate the use of the mobile nylon bag technique for predicting the ileal digestibilty of AA for feeds containing antinutritional factors.

Amino Acids↗
PubMed2001

Comparison of photovoltaic behaviors for horseradish peroxidase and its mimicry by surface photovoltage spectroscopy.

Surface photovoltage spectroscopy (SPS) was chosen to study the photovoltaic behavior of horseradish peroxidase (HRP), hemin and immobilized hemin (poly(NIPAAm/MBA/hemin)). Different photovoltaic behaviors were observed in these three systems. In air, similar SPS curves were found for HRP and poly(NIPAAm/MBA/hemin) with different response intensities. However, poly(NIPAAm/MBA/hemin) showed a wider changing range upon increasing the positive and negative bias to 1.0 V. The SPS of hemin showed a total different behavior when an external positive potential was applied. In vacuum, clearly different photovoltaic behaviors were found. Moreover, the response value decreased when HRP was exposed to O2, the SPS intensity was different from that in air, and could be altered by changing the external biases. On the other hand, the SPS could not be changed before and after poly(NIPAAm/MBA/hemin) was exposed to O2. These differences may result from different chemical microenvironments for hemin in HRP versus that in poly(NIPAAm/MBA/hemin). It could be concluded that H2O and O2 were important factors affecting the photovoltage response in HRP, but only H2O played this important role in poly(NIPAAm/MBA/hemin).

Horseradish Peroxidase↗
PubMed2001

Clear cell odontogenic carcinoma: a clinicopathologic and immunocytochemical study of 5 cases.

CONTEXT: Odontogenic tumor composed predominantly of clear cells is a rare neoplasm of the jaws that was initially designated as clear cell odontogenic tumor. Subsequent reports in the literature, however, all have indicated that this tumor exhibits an aggressive behavior characterized by infiltrative local growth, recurrence, or metastases. OBJECTIVE: To ascertain the clinicomorphologic features and biologic behavior of this tumor group, we present 5 additional cases using the term clear cell odontogenic carcinoma. DESIGN: Histologic and immunohistochemical examinations were performed on clear cell odontogenic carcinomas from 5 patients. Clinical and follow-up data were recorded, and the literature was reviewed. RESULTS: The patients were 1 man and 4 women with an average age of 42.4 years at diagnosis. Three tumors occurred in the mandible and the other 2 in the maxilla. Four of the 5 cases occurred in the anterior or premolar areas of the jaws, appearing as poorly marginated radiolucencies. All cases consisted of islands and sheets of large clear cells and small basaloid cells with scanty eosinophilic cytoplasm, which were separated by thin, mature, fibrous septae. The tumors were unencapsulated and showed aggressive infiltration of the surrounding muscle and perineural tissues. Most of the clear cells contained cytoplasmic glycogen. Immunocytochemically, the tumor cells were positive for pan-keratin, cytokeratin 19, and epithelial membrane antigen, but were negative for vimentin, S100 protein, desmin, smooth muscle actin, human melanoma antigen (HMB-45), and alpha(1)-antichymotrypsin. Follow-up data showed 4 of 5 patients to have multiple local recurrences, and 1 of these 4 had submandibular lymph node metastasis and a fatal outcome due to uncontrollable tumor growth. CONCLUSION: These results suggest that odontogenic clear cell neoplasms are at least low-grade malignancies and should be classified as carcinomas.

Adenocarcinoma, Clear Cell↗
PubMed2001

Effect of lysophosphatidylcholine on expression of vascular endothelial growth factor in ECV304 cells.

AIM: To determine the effect of lysophosphatidylcholine (LPC) on the expression of vascular endothelial growth factor (VEGF) in human umbilical veins endothelial cell line (ECV304). METHODS: VEGF protein production from ECV304 cells was determined by enzyme-linked immunosorbent assay (ELISA). VEGF protein and its receptor were also examined by immunohistochemical staining. After culturing for 24 h with LPC, VEGF mRNA expression in ECV304 was examined by in situ hybridization. RESULTS: Cultured ECV304 cells could express VEGF receptor and a strong expression of VEGF receptor was induced by LPC 5 mg/L. LPC upregulated VEGF protein secreted from the ECV304 cells in a time- and concentration-dependent manner and LPC also stimulated VEGF mRNA expression in the ECV304 cells. CONCLUSION: LPC could induce a strong expression of VEGF in ECV304 cells.

Cell Line↗
PubMed2001

VEGF induced hyperpermeability in bovine aortic endothelial cell and inhibitory effect of salvianolic acid B.

AIM: To examine the effect of recombinant human vascular endothelial growth factor (VEGF) on the low density lipoprotein (LDL) permeability of bovine aortic endothelial cells (BAEC) and the inhibitory effect of salvianolic acid B in vitro. METHODS: The confluence BAEC monolayers were cultured with normal medium and with medium containing VEGF or salvianolic acid B at various concentrations and for various time periods. The iodine labeled LDL flux across the monolayers was then performed, and radioactivity was measured by SN-695 automatic liquid scintillation counter. RESULTS: Addition of purified human recombinant VEGF to the BAEC monolayers could significantly increase the permeability of the monolayer to 125I-LDL (P < 0.01). The permeability-increasing activity of VEGF on the BAEC monolayers was both dose and time dependent. Salvianolic acid B could markedly inhibit the VEGF-induced hyperpermeability in BAECs (P < 0.01). CONCLUSION: VEGF plays a role in the formation and development of atherosclerosis, and salvianolic acid B has inhibitory effect on VEGF-induced hyperpermeability in BAEC.

Animals↗
PubMed2000

Increased fractal complexity of the epithelial-connective tissue interface in the tongue of 4NQO-treated rats.

The effect of the carcinogen 4-nitroquinoline 1-oxide (0.001% in drinking water) on the irregularity of the epithelial connective tissue interface (ECTI) of the ventral surface of the tongue was quantified in Dark Agouti and Wistar Furth rats. Histological tongue sections stained with the Azan-Mallory method were digitised (111 images, resolution 1 pixel = 3.1 microns), and the limit between epithelium and stroma of the ventral surface was extracted and analysed using a fractal geometry technique (local connected dimension). The results showed that although none of the images included carcinomas on the ventral surface of the tongue (all cases had other oral carcinomas), the epithelial profiles of the treated cases showed a statistically significant increase in irregularity when compared to controls. Canonical discriminant analysis of the parameters describing the irregularity of the ECTI classified 81.1% of the images in the original groups (treated or control). Fractal analysis is capable of detecting subtle architectural changes in the oral epithelium of the rat occurring after exposure to the carcinogen, even when full malignant transformation has not yet taken place. Fractal analysis, which may prove useful for monitoring the progression of carcinogenesis in this animal model, is a morphometrical parameter in the diagnosis of oral epithelial dysplasia.

4-Nitroquinoline-1-oxide↗
PubMed2000

Three new saponins from Tribulus terrestris.

Three new steroidal saponins 1-3, together with five known steroidal saponins, L-mannitol and an inorganic salt were isolated from Tribulus terrestris L. (Zygophyllaceae). The structures of the new steroidal saponins were elucidated as hecogenin 3-O-beta-xylopyranosyl(1-->3)-beta-glucopyranosyl(1-->4)-beta-galactopyr anoside (1), hecogenin 3-O-beta-glucopyranosyl(1-->2)-beta-glucopyranosyl(1-->4)- beta-galactopyranoside (2) and 3-O-[beta-xylopyranosyl(1-->2)-[beta-xylopyranosyl(1-->3)]-beta- glucopyranosyl(1-->4)-[alpha-rhamnopyranosyl(1-->2)]-beta-galactopyranos yl]- 26-O-beta-glucopyranosyl-22-methoxy-(3 beta,5 alpha,25R)-furostan-3,26-diol (3). Structure elucidation was accomplished by 1D and 2D NMR spectra (13C-1H COSY, HMQC, HMBC, 1H-1H COSY, TOCSY, and NOESY), mass spectrometry (FABMS, ESIMS) and chemical methods.

Carbohydrate Sequence↗
PubMed2000

Unicystic ameloblastoma: a clinicopathologic study of 33 Chinese patients.

The term unicystic ameloblastoma refers to those cystic lesions that show clinical, radiographic, or gross features of a jaw cyst, but on histologic examination show a typical ameloblastomatous epithelium lining part of the cyst cavity, with or without luminal and/or mural tumor growth. To ascertain the clinicomorphologic spectrum and biologic behavior of this tumor group, the clinicopathologic features of 33 unicystic ameloblastomas from Chinese patients were studied. This series represents approximately 19% of all cases of ameloblastoma accessioned in the authors' hospital during a 15-year period. Twenty-one patients were male and 12 were female, for a total of 33 patients. The age at diagnosis ranged from 8 to 60 years (mean, 25.3 yrs) and peaked at the second and third decades (70%), Thirty tumors (91%) occurred in the mandible and three in the maxilla. Of the 29 patients with a radiographic record, an expansive unilocular radiolucency was seen in 22 cases, and was multilocular in seven cases. Microscopically, all tumors demonstrated a generally monocystic growth pattern. Eight tumors were simple cystic, 10 comprised intraluminal tumor nodules, and the remaining 15 had a conspicuous component of infiltrative tumor islands in the cyst capsule. The cystic tumor linings invariably showed, at least in part, a typical ameloblastomatous pattern that was often accompanied by epithelial areas of various histologic appearance. Follow up of 29 patients revealed no recurrence in less than 4 years of follow up, but did reveal a 35% recurrence rate at more than 4 years of follow up. The average interval to recurrence was approximately 7 years. Recurrence also appeared to relate to histologic subtypes of unicystic ameloblastoma, with those invading the fibrous wall having a rate of 35.7%, but other types having a rate of 6.7%. Despite the fact that unicystic ameloblastoma may, in general, compare favorably with its solid or multicystic counterpart in terms of clinical behavior and response to treatment, the subsets of the maxillary lesions or tumors containing invading islands in the fibrous wall could have a high risk of recurrence. Furthermore, recurrence of unicystic ameloblastoma may be long delayed, and a long-term postoperative follow up is essential to the proper management of these patients.

Adolescent↗
PubMed1999

Effects of hypoxia/reoxygenation and cytokines on adhesion of leukocytes to cerebral microvascular endothelial cells.

AIM: To study the influence of hypoxia/reoxygenation (H/R) on the adhesion of neutrophils (Neu) and monocytes (Mon) to cultured bovine cerebral microvascular cells induced by tumor necrosis factor alpha (TNF-alpha) or interleukin 1-alpha (IL-1 alpha). METHODS: Bovine cerebral microvascular endothelial cells (CMEC) and smooth muscle cells (CMSMC) were exposed to normoxia or H/R in the presence or absence of TNF-alpha (IL-1 alpha). The number of adhesions of Mon and Neu to CMEC and CMSMC was measured by flow cytometry. RESULTS: CMEC were subjected to hypoxia for 2 h followed by reoxygenation with TNF-alpha (2 micrograms.L-1) for 2 h, the adhesion rate of CMEC for Mon and Neu were increased to 35.0% +/- 0.9% and 36.0% +/- 0.6% (the TNF-alpha treated group was 28.9% +/- 1.1% and 28.8% +/- 1.3%), respectively. CMSMC were treated as above, the adhesion rate of Mon and Neu was enhanced to 49.9% +/- 0.4% and 43.9% +/- 1.4% (the TNF-alpha treated group was 34.0% +/- 1.9% and 34.0% +/- 1.3%), respectively. CMEC and CMSMC were treated by IL-1 alpha, similar results were obtained. CONCLUSION: H/R enhanced the adhesion of Mon and Neu to CMEC and CMSMC induced by TNF-alpha or IL-1 alpha.

Animals↗
PubMed1999

Antagonistic effects of Ginkgo biloba extract on adhesion of monocytes and neutrophils to cultured cerebral microvascular endothelial cells.

AIM: To study the action of Ginkgo biloba extract (GbE) on tumor necrosis factor (TNF-alpha)-induced adhesion of monocytes (Mon) and neutrophils (Neu) to cultured cerebral microvascular endothelial cells. METHODS: TNF-alpha-induced endothelial adhesivity toward Mon and Neu was studied using bovine cerebral microvascular endothelial cells (BCMEC) in vitro. The number of Mon and Neu adhering to the BCMEC monolayers was determined by flow cytometry. RESULTS: Pretreatment of BCMEC with TNF-alpha increased Mon and Neu adhesion to BCMEC from 12.5% +/- 0.2% to 31.3% +/- 0.5% and from 13.8% +/- 0.4% to 32.1% +/- 0.5%, respectively. GbE (1-100 mg.L-1) inhibited the effect of TNF-alpha in a concentration-dependent manner. E-selectin mAb (1 mg.L-1) blocked Mon and Neu adhesion to BCMEC induced by TNF-alpha. CONCLUSION: The inhibition of GbE on Mon and Neu adhesion to BCMEC was mediated through the suppression of E-selection expression.

Animals↗
PubMed1999

Altered placental glutathione S-transferase foci as a tumor marker during rat lingual carcinogenesis.

OBJECTIVE: To evaluate the value of placental glutathione S-transferase (GST-P) as a tumor marker during lingual carcinogenesis in two strains of rats. METHODS: Dark-Agouti (DA) and Wistar/Furth (WF) rats were given with 4-nitroquinoline 1-oxide (4NQO) in drinking water with a defined treatment schedule. Immunocytochemical expression of GST-P was studied using experimental materials obtained at 2, 4, 8, 12, 16, and 26 weeks of 4NQO treatment. GST-P+ foci in the tongue epithelium were counted for each experimental rat and quantitative data were compared between groups. RESULTS: The animal experiment demonstrated marked differences in tumorigenicity between the two strains of rats, with DA exhibiting earlier responses to 4NQO and having a higher tumor incidence than WF rats. GST-P+ foci occurred earlier in the tongue mucosa of DA rats than in that of WF. With continued 4NQO application, there was a progressive increase in the number and size of GST-P+ foci in both strains of animals, but those of DA groups revealed a greater increase in comparison to those of WF groups. CONCLUSIONS: These results indicate that GST-P is a sensitive marker that may reflect the metabolic patterns of preneoplastic cells during early stages of rat lingual carcinogenesis, and that rapid expansion of such putative initiated cells may have the propensity for malignant transformation.

4-Nitroquinoline-1-oxide↗
PubMed1998

Orthokeratinized odontogenic cyst: a clinicopathological and immunocytochemical study of 15 cases.

AIMS: Intraosseous jaw cysts with a solely orthokeratinized lining epithelium have been suggested to differ from the typical odontogenic keratocysts (OKC) by exhibiting a less aggressive behaviour. We report 15 cases of such cyst type under the term of 'orthokeratinized odontogenic cyst (OOC)' and compared their clinical, histological and immunocytochemical features with that of OKC. METHODS AND RESULTS: The cysts of the present series were all solitary lesions, occurred mostly in young male patients, and showed a predilection for the posterior mandible areas. Follow-up of 14 patients, nine of whom were treated by simple enucleation, revealed no recurrence over a period of 3.5-12 years after surgery. None of the patients had any association with the naevoid basal cell carcinoma syndrome. Furthermore, histological and immunocytochemical comparison between OOC and OKC revealed marked differences in their morphology and epithelial expression. The lining epithelium of OOC lacked the typical features of OKC and appeared to show a lower proliferative activity. CONCLUSION: These findings suggest that OOC is clinicopathologically separate from other types of odontogenic cysts and may thus constitute a distinct clinical entity.

Adult↗
PubMed1998

Experimental odontogenic cysts induced by in vitro 4-nitroquinoline 1-oxide (4NQO) treatment of F344 rat incisor tooth germs.

This study was designed to establish an experimental animal model for elucidating the early stages of odontogenic cysts and tumors. It involves the in vitro treatment of tooth germs with 4-nitroquinoline 1-oxide (4NQO) at the early bell stage and their subsequent transplantation into the kidney subcapsular space. While all tooth germ transplants of the control group not exposed to the carcinogen showed continued tooth development with no pathological lesions, 21 of 23 4NQO-treated tooth germs developed into similar appearing keratinized cysts with or without associated tooth structures. The remaining two transplants failed to develop cysts and formed only a tooth. The present experimental procedure was effective in inducing keratinized cystic lesions that exhibit some similarities to human odontogenic keratocysts or primordial cysts.

4-Nitroquinoline-1-oxide↗