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The cheek for reconstructive purposes if divided into a medial or lateral region. Some cheek defects are presented and the methods of their closure explained. Bilobed, trilobed and cranial pedicled rotation flaps, used to close lateral defects, are also described.
By using microscopic, fluorometric, and immunologic methods, we have assessed the effects of eosinophil granule proteins on the microcirculation of the hamster cheek pouch. The plasma clearance of FITC-dextran 150 (FITC-dx 150) was used to quantify macromolecular transport. Topical application of major basic protein (MaBP) at 0.1 and 0.5 nM increased the clearance of FITC-dx 150 from a base line of 591 to 1283 and 1966 nl/60 min/g, respectively. Numerous muscle fasciculations were also observed with the 0.5 nM dose of MaBP. Eosinophil cationic protein (ECP) was as potent as MaBP and caused an increase in the clearance of FITC-dx 150, 0.5 nM eliciting 2156 nl/60 min/g. In contrast, topical application of 0.5 nM eosinophil peroxidase (EPO) increased clearance of FITC-dx 150 to a significantly lower level, 1113 nl/60 min/g. Supplementing 0.5 nM EPO with 1 nM H2O2 enhanced the clearance of FITC-dx 150 to 2404 nl/60 min/g, suggesting separate cationic charge and enzymatic activity-related effects. Compared with these eosinophil granule proteins, eosinophil-derived neurotoxin (EDN) required a 2000-fold higher concentration (1 microM) to elicit a significant increase in the clearance of FITC-dx 150 (1505 nl/60 min/g). Neither EPO, EPO+H2O2, ECP, nor EDN at 1 mM caused muscle fasciculations. Quantitative analysis of the suffusates from the preparations exposed to these eosinophil proteins did not contain histamine. Our results demonstrate that MaBP, ECP, EPO, and EDN increase microvascular transport in the hamster cheek pouch and that this increase is independent of endogenous histamine release. The concentrations of eosinophil granule proteins causing increased vascular permeability are achieved in many pathologic conditions suggesting that the granule proteins play an important role in disease.
An interlaboratory study was carried out to determine the feasibility and reliability of a method using the hamster cheek pouch as a model for assessing the potential irritative properties of substances intended to be applied to the lips or other mucous membranes. The test substances were applied once daily to both pouches for 14 consecutive days. Local and general tolerances were appraised throughout the study. At the end of the study, histologic examination of the pouches and the main organs was performed. Results of the feasibility study, conducted on various types of commercial products, indicated that this model is suitable for preparations of various consistence and composition. Results of the reliability study, carried out on gel-type preparations containing various concentrations of a known irritant, sodium lauryl sulfate, indicated that the method elicits a dose-dependent reaction for this compound. This hamster cheek pouch method was reproducible for the various parameters under consideration: local tolerance, general tolerance, histologic examination. For all products, results were in good agreement among the various laboratories participating in the study. The French regulatory authorities of the Fraud Repression Department have accepted it as an official method for the evaluation of the potential irritative properties of cosmetics and hygiene products intended to be applied to the lips or other mucous membranes.
The role of leukocyte sticking and permeability changes in the variation of perfused capillaries induced by ischemia reperfusion was studied in the hamster cheek pouch microcirculation. The drugs utilized were the antiperoxidative agents allopurinol, the calcium antagonists verapamil and diltiazem, and phenidone and adenosine, which inhibit leukotriene formation as well as leukocyte adhesion to the endothelium. The microvasculature was visualized by a fluorescence technique. Ischemia was induced by clamping the cheek pouch for 30 minutes followed by 30 minutes of reperfusion. The increase in permeability, the perfused capillary length and the number of adhering leukocytes to venular vessel wall were measured. Ischemia and reperfusion were associated with increased permeability, increased number of leukocytes sticking to the venular wall, and decreased number of functional capillaries. Microvascular injury evidenced by increased permeability was apparent in the first 5 min of ischemia. All the drugs decreased the number of leukocytes sticking to the venular wall; allopurinol, verapamil and adenosine reduced the increase in permeability, whereas phenidone and diltiazem were effective only during ischemia. In addition verapamil and adenosine preserved capillary blood flow during reperfusion. In conclusion, leukocyte sticking is correlated with increased microvascular permeability, but not with decreased perfusion of the capillary bed. These data suggest that leukocytes did not play a prominent role in the reduction of functional capillaries at the end of reperfusion.
By means of in vivo microscopy the influence of human, rat, and hamster purified salivary kallikreins upon the microvessels was studied in rat mesentery and hamster cheek pouch. Dilatation of arterioles, a decrease of the venule diameter, and an increase in the number of active capillaries was revealed. The species and organ peculiarities of these effects were described. The mesentery and the cheek pouch homogenates, albumin proteins, histamine and some amino acids were capable of activating the salivary kallikreins.
A 28-year-old female had a severe depressed deformity of the left cheek due to false local injection of ZnCl2 into her buccal mucosa instead of an anesthetic. After several attempts at plastic surgery in another hospital with unsatisfactory results, she was treated surgically in our clinic using cheek skin expanded by a tissue expander. The outcome was satisfactory.
The present study was designed to determine whether increased vascularity occurs during malignant transformation of human oral cheek epithelium. Nine normal (N) samples were taken from the resection margins of benign lesions; the pathological lesions were classified as chronic inflammation (CI; n = 11), fibrous hyperplasia (FH; n = 12), lichen planus (LIP; n = 8), dysplasia (DYS; n = 5), squamous cell carcinoma (SCC; n = 25; well differentiated [SCCWD]; n = 10; moderately to poorly differentiated [SCCMPD]; n = 15) and epithelium adjacent to carcinomas (EAC; n = 6). Sections were stained with monoclonal antibody (mAb) against vimentin using an ABC immunoperoxidase technique. All blood vessels present within a depth of 0.9 mm of lamina propria were quantified irrespective of their morphology. The blood vessel parameters quantified were volume density (VVBV, CT), number per unit area (NABV, CT), length per unit volume (LVBV, CT) and mean transverse sectional area (ABV). VVBV, CT increased significantly between normal and all pathological groups. Amongst the pathological groups, statistical differences were detected between CI and SCC, CI and EAC, FH and SCCWD, FH and EAC, LIP and SCC, LIP and EAC, DYS and SCCWD and DYS and EAC. The EAC group had the highest VVBV, CT and the values of NABV, CT and LVBV, CT were significantly higher in all the pathological groups when compared with the normal group. No significant differences were detected between any of the pathological group. The parameter ABV increased significantly between normal and DYS, FH, SCC, EAC, FH and EAC, FH and SCC, CI and EAC, CI and SCC, LIP and EAC and LIP and SCC. Spearman rank correlations detected a positive correlation between the severity of oral lesions and all of the blood vessel parameters. We conclude that a mAb against vimentin improved the identification of smaller blood vessels and the blood vessel data suggest that angiogenesis occurs in premalignant and malignant lesions of human oral cheek epithelium. Angiogenesis seems to play an essential role in sustaining the actively growing and transforming cells.
We obtained immunohistochemical profiles of several keratin proteins during experimentally induced carcinogenesis in hamster cheek-pouch mucosa using a polyclonal antibody (TK; detecting keratins with molecular masses of 41-65 kilodalton) and two monoclonal antibodies (KL1, 55- to 57-kilodalton keratins; PKK1; 40-, 45- and 52.5-kilodalton keratins). The squamous epithelium of normal pouch mucosa exhibited positive TK staining in all layers, KL1 staining in the spinous layer and PKK1 staining in the basal layer, thus indicating a regional or zonal distribution pattern. Epithelia undergoing basal hyperplasia showed irregular localization of PKK1 binding, while hyperkeratinized lesions exhibited the binding pattern found in normal epithelium. In case of epithelial dysplasia, there was reduced KL1 staining in spinous cells and decreased PKK1 staining in the basal and parabasal layers. Papillomas exhibited a rather zonal distribution of keratin staining. All squamous-cell carcinomas, irrespective of their degree of keratinization and infiltration pattern, showed slight or no PKK1 staining. Such lesions were only positive for KL1-detectable keratins in keratinizing tumour cells and exhibited an irregular distribution of TK binding. The expression of keratin proteins during carcinogenesis in hamster cheek-pouch mucosa may parallel that of keratins in human squamous-cell carcinomas originating in the oral mucosa.
A mild and controlled acute inflammatory reaction in hamster cheek pouch was created without any exogenous, but rather by locally activated and liberated, mediators. A pressure of 60 mm Hg was applied to part of the everted cheek pouch eight times with a 10-min recovery period in between. The microvascular response was followed by intravital microscopy and the permeability changes were monitored with intravital fluoroscopy and intravenous FITC dextran (mol wt 150,000). The number of extravasated polymorphonuclear leukocytes (PMNLs) was calculated by a new, whole tissue, histological technique. In three experimental groups (-)-terbutaline (beta 2-receptor agonist) 0.05 mg/100 g body wt., (+)-terbutaline 0.05 mg/100 g body wt., and indomethacin 2 mg/100 g body wt. was given intravenously before pressure was applied. A fourth group, with no drug given, served as control. There was a rapid increase in the number of FITC dextran leakages and extravasated PMNLs in the control group. Indomethacin almost completely inhibited FITC dextran permeability and extravasation of PMNLs. The beta 2 agonist markedly diminished the number of FITC dextran leakages for 75 min. The number of extravasated PMNLs was also reduced. Treatment with (+)-terbutaline, which is supposed to have no beta 2-receptor effect, gave a slight reduction in number of FITC dextran leakages and almost a complete inhibition of PMNL extravasation. Thus we conclude that indomethacin is a very potent antiinflammatory agent even in the early phase of inflammation. (-)-Terbutaline diminished the inflammatory response, probably by preventing endothelial gap formation. (+)-Terbutaline prevented PMNL extravasation either by interaction with the PMNL itself or with the endothelium.
The effects of removal of the submandibular gland (sialoadenectomy) and administration of human urinary epidermal growth factor on the 9,10-dimethyl-1,2-benzanthracene-induced tumor formation were investigated with the use of a hamster cheek pouch model. Syrian hamsters were treated with 0.5% 9,10-dimethyl-1,2-benzanthracene for 6 weeks. Thereafter hamsters in group 1 underwent a sham operation and those in groups 2 and 3 underwent a sialoadenectomy. Subsequently, hamsters in groups 1 and 2 were given 0.9% sodium chloride and group 3 received the human urinary epidermal growth factor at a dose of 0.25 mg/kg body weight subcutaneously three times a week for 8 weeks. Sixteen weeks after the start of the experiment, the mean number of tumors that were less than 3-mm in diameter in groups 1 and 3 was significantly greater than that in group 2 (p < 0.05). The overall incidence and mean number of all carcinomas irrespective of size showed no differences among the experimental groups. These results indicate that epidermal growth factor synthesized in the submandibular gland may enhance the induction of cheek pouch tumor.
The effects of Vaccinium myrtillus anthocyanosides (VMA) on ischaemia reperfusion injury were investigated in the hamster cheek pouch microcirculation. Ischaemia was induced by clamping the cheek pouch for 30 min followed by 30 min of reperfusion. The microvasculature was visualized by a fluorescence technique. VMA [10 mg (100 g body weight)-1] were orally administered for 2 and 4 weeks. The number of adhering leukocytes to venular vessel walls, the perfused capillary length, the increase in permeability, the arteriolar diameter changes were determined. Ischaemia and reperfusion were associated with increased number of leukocytes sticking to venules, decreased number of perfused capillaries, and increased permeability. VMA decreased the number of leukocytes sticking to the venular wall and preserved the capillary perfusion; the increase in permeability was significantly reduced after reperfusion. VMA saved the arteriolar tone and induced the appearance of rhythmic diameter changes of arterioles. These results demonstrate the ability of Vaccinium myrtillus anthocyanosides to reduce microvascular impairments due to ischaemia reperfusion injury, with preservation of endothelium, attenuation of leukocyte adhesion and improvement of capillary perfusion.
Chinchillas are herbivorous rodents with teeth that all grow continuously. In captivity, they are commonly affected by dental disease. As the range of dental disease occurring in wild chinchillas is unknown, the dentition of museum specimens originally obtained from the wild was assessed and compared with specimens prepared from captive-bred animals. Skulls from wild-caught chinchillas showed minimal evidence of dental disease and the teeth were all short, cheek-tooth lengths averaging 5.9 mm. Cheek-tooth lengths in zoo specimens (average 6.6 mm), clinically normal (average 7.4 mm) and captive-bred animals with dental disease (average 10 mm) were significantly elongated by comparison (P<0.0001). Captive-bred specimens showed a wide range of tooth-related lesions. These results suggest that some aspect of captivity is responsible for the development of dental disease in chinchillas. It is suggested that the diet (its physical form and composition) is the main aetiological factor, and that provision of a diet closely matching that of wild chinchillas should significantly reduce the incidence of dental disease in captive animals.
To examine the role of reactive oxygen species on the invasive phenotype of cancer cells, we overexpressed manganese- and copper-zinc-containing superoxide dismutases (MnSOD, CuZnSOD) and catalase (Cat) in hamster cheek pouch carcinoma (HCPC-1) cells in vitro using adenoviral vector-mediated gene transfer. Hamster cheek pouch carcinoma cells were transduced with these adenoviral vector constructs alone, or in combination, at concentrations [i.e., multiplicity of infectivity (MOI)] of 100 MOI each. The Escherichia coli beta-galactosidase reporter construct was used as a control virus. Protein expression was examined by Western blot analysis and enzymatic activities were measured using spectrophotometry. To observe the effects of transgene overexpression on in vitro tumor cell invasion, we used the membrane invasion culture system, an accurate and reliable method for examining tumor cell invasion, in vitro. This assay measures the ability of tumor cells to invade a basement membrane matrix consisting of type IV collagen, laminin, and gelatin. MnSOD overexpression resulted in a 50% increase in HCPC-1 cell invasiveness (p < .001); co-overexpression of MnSOD with Cat partially inhibited this effect (p < .05). Moreover, co-overexpression of both SODs resulted in a significant increase in invasiveness compared with the parental HCPC-1 cells (p < .05). These changes could not be correlated with the 72 kDa collagenase IV or stromolysin activities using zymography, or the downregulation of the adhesion molecules E-cadherin or the alpha4 subunit of the alpha4beta1 integrin. These results suggest that hydrogen peroxide may play a role in the process of tumor cell invasion, but that the process does not rely on changes in matrix metalloproteinase activity in the cells, or the expression of cell adhesion molecules.
An ischaemic insult is produced on a hamster's cheek pouch under intravital-microscopic control. Recirculation and the condition of the nutritive flow is studied. Three hours ischaemia at 36 degrees C will produce only a slight immediate reaction. Microbleedings, thrombus formation and oedema are recorded later. The nutritive blood flow is unevenly distributed. Eight hours ischaemia at 22 degrees C will produce less disturbed microcirculation than a shorter period at body temperature. Tissue viability after an ischaemic insult is dependent on mainly two factors. First, the ability of parenchymal cells to withstand hypoxic injury and secondly the ability of the microvasculature to resume blood flow. Tissue temperature has been found to be a major determinant of the balance between metabolic rate and nutritive blood flow. Studies in the past have utilised the skin of the rat and the ear of the rabbit as tissue models for ischaemic injury (Lindan, 1961; Willms-Kretschmer and Majno, 1969). The aim of our studies is to elucidate the early phase of recovery after an ischaemic insult in the cheek pouch. This tissue is thin and well suited for vital microscopic studies. and pressure may be applied with little shear stress. We have chosen a tissue without parenchymal elements, thus it is to a large extent composed only of a vascular network with its accompanying connective tissue. Our study of microcirculatory events will thus show the effect of ischaemic insults on the microvasculature.
We report a rare case of pigmented squamous cell carcinoma (SCC) of the cheek skin probably arising from solar keratosis. An 80-year-old man was referred to our clinic because of a black skin nodule in the right cheek. The nodular lesion was 1 cm in diameter, dome-shaped, hard, sharply demarcated, partially erosive and telangiectatic at the border. The lesion was completely excised under the clinical diagnosis of probable seborrheic keratosis. Microscopically, cutaneous horn and mildly atypical squamous epithelia suggestive of previous solar keratosis were present in the surface of the lesion. The lesion consisted of atypical squamous cells with keratinization and intercellular bridges, and it was regarded as SCC. The SCC cells were seen to invade lightly into the upper dermis, where lymphocytic infiltrations and melanophages were noted. Characteristically, heavy deposition of melanin pigment was recognized in the SCC cells as well as in proliferated dendritic and pigment blockade melanocytes that were scattered or colonized within the SCC cell nests. Masson-Fontana stain revealed numerous melanin granules in the SCC cells, as well as in dendritic and pigment blockade melanocytes. Immunohistochemically, the SCC cells were positive for cytokeratins and epithelial membrane antigen, and negative for S-100 protein and HMB45 antigen. Dendritic and pigment blockade melanocytes were negative for cytokeratins, epithelial membrane antigen, and HMB45 antigen, but positive for S-100 protein. The present case suggests that SCC cells of the skin may induce proliferation of melanocytes. The differential diagnosis and the histogenesis of pigmented SCC of the skin are discussed.
The development of the mandibular cheek teeth was examined, both visually and by radiograph, in a group of 76 Hereford cross Friesian steers, of which all but one were slaughtered at the same weight - 464 kg (1020lb). The age of the youngest animal was 1 year 0.3 months whereas the slaughter ages of the others ranged from 1 year 3 months to 1 year 8 months. The first molar was fully erupted and crown and root formation complete in all but the youngest steer. In the other five cheek teeth there were one or more significant differences between the mean ages of tooth development stages as assessed by radiograph. Cattle of 1 year 3 months could not be absolutely distinguished from those of 1 year 8 months by intra-oral second molar eruption. Examination of stages of development seen radiographically gave a maximum age range of 4 months before differentiation. In this study, development of the first two molars was in advance of the three permanent premolars and in these latter teeth the second premolar was the most developed.
The present experiment tested the hypothesis that 22% body fat based on the Mellits and Cheek (1970) regression equation is a minimum or 'trigger' level of fatness required to maintain regularity of menstrual cycles. The validity of the regression equation was cross-validated against densitometric estimates of body fat in 30 athletes (track, gymnastic, crew) and 30 non-athletes who were below 22% fat. For the total sample, the validity correlation was r = 0.47 between body fat (density) and body fat (regression equation); it was r = 0.75 for athletes and r = 0.47 for non-athletes. For all subjects, 60% had regular menses, 27% were oligomenorrheic and 13% were amenorrheic. The lowest body fat (density) was 12.8% for an athlete with a regular cycle and 12.2% for an oligomenorrheic athlete. The results show that: the Mellits and Cheek (1970) height-weight based regression equation to determine fatness is not valid for women below 22% fat, and 13% body fat (not 22%), should be considered an upper-bound estimate of a minimum level of fatness associated with normal ovulatory cycles.
Six different monoclonal antibodies (MAbs) to human chorionic gonadotropin (hCG) were evaluated for radioimmunodetection in Golden Syrian Hamsters bearing a human choriocarcinoma in the cheek pouch (188-516 mIU of hCG/g). The affinity of three antibodies when determined were high and five of the antibodies were of IgG1 subclass. After i.v. injection of Staphylococcus Protein A (SPA) affinity purified radioiodinated antibodies, tissue distribution studies demonstrated that antibody 061 had higher target-to-nontarget ratios than the other five antibodies. The mean tumor:muscle ratio of 131I-MAb 061 was 27.5 in four animals, where the mean tumor:muscle ratio of four animals injected with 131I-labeled control monoclonal IgG1 Kappa from MOPC-21 murine myeloma (MOPC-21) was only 2.2. Sharp images of the cheek pouch tumor were obtained at five days following a tracer dose of 131I-061 MAb, but not with the same dose of a 131I-MOPC-21.