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Ruptured aortic aneurysms after endovascular repair is rare, particularly in the absence of type I or type III endoleaks. In such cases, a thorough investigation into the causes is imperative, including the consideration of an underlying malignancy. We report a case involving a 78-year-old woman who experienced abdominal aortic aneurysm rupture 4 years after aortic endograft treatment. We explanted the endograft and performed aortobi-iliac bypass. Initial aortic thrombus pathological analysis revealed atherosclerosis. However, the patient returned 4 months later with multiple lesions suggestive of metastases, and a reevaluation of the pathology slides uncovered a diagnosis of angiosarcoma., Competing Interests: None., (© 2024 The Author(s).)

Background: Burn injuries pose a significant burden on both patients and healthcare systems. Yet, costs arising from the consumption of resources by these patients are rarely examined in Canada., Objective: The objective of this study was to assess real-world costs resulting from the initial hospitalization of patients admitted to a major burn unit in Quebec, Canada., Methods: A cost study based on a retrospective cohort was undertaken using in-hospital economic data matched to hospital chart data. Our cohort included all burn-injured patients admitted between April 1, 2017, and March 31, 2021, to the hospital's major burn unit during their initial hospitalization. Descriptive statistics were tabulated for sociodemographic and economic data. Costing data were analyzed unstratified and stratified according to burn severity (i.e., ≥ 20% of total body surface area [TBSA] vs. < 20%). Costs were presented in CAD 2021., Results: Our cohort included 362 patients, including 65 (18%) with TBSA ≥ 20%. The average initial hospitalization cost was $32,360 ($22,783 for < 20% TBSA and $76,121 for ≥ 20% TBSA)., Conclusion: Findings reveal that the total cost of the initial hospitalization, from a public hospital perspective, was $11,714,348. Our study underlines the substantial burden associated with burns and highlights the need for long-term cost evaluations., Competing Interests: Declarations of interest None., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Polymer ring stent grafts from Endologix are reliable to treat challenging abdominal aortic aneurysm anatomy (hostile neck and tortuous or narrow iliac arteries). Rare cases of anaphylactoid reactions have been reported during the filing time of the graft rings due to polymer leakage. Management with amines, an antihistamine drug, and supportive care quickly stabilized both of our patients, which permitted the continuation and completion of their surgery. In our experience, there was no death-related events nor negative impact on patients surgical and clinical outcomes. We report on polymer leakage using the Ovation IX and ALTO stent grafts resulting in an anaphylactoid reaction., Competing Interests: None., (© 2024 The Authors.)

Background: Uniportal video-assisted thoracoscopic surgery (VATS) segmentectomy is gaining worldwide acceptance, but experience in North America is still limited. We report a North American multicenter comparison of uniportal vs. multiportal VATS segmentectomy., Methods: We performed an institutional review board-exempt retrospective chart review on prospectively collected databases at two North American centers, from January 2012 to December 2020. We included all VATS segmentectomy patients and excluded emergent cases (n=1), patients with incomplete records (n=2), and segmentectomy performed in conjunction with another type of lung resection (n=1). We recorded patient demographics, perioperative data, 30-day postoperative complications and compared outcomes between cohorts. We provided descriptive statistics for each group. We calculated propensity score matching and paired patients 1:1. We defined P values less than 0.05 as statistically significant., Results: We performed a total of 423 VATS segmentectomies, 181 uniportal (42.7%) vs. 242 multiportal (57.2%). Indications for surgery were primary lung cancer (n=339), metastatic (n=41), benign disease (n=40), and other (n=3). We staged 85.1% of patients preoperatively with positron emission tomography-computed tomography (PET-CT) scan according to National Comprehensive Cancer Network (NCCN) guidelines. Propensity score matching generated 156 patients on each group. Operating time was significantly lower in the uniportal group compared to multiportal (130 vs. 161 min respectively, P<0.001). We found no difference in estimated blood loss, Clavien-Dindo class III-IV complications, conversion to thoracotomy, R0 resection rate, nodal upstaging, hospital length of stay, 30-day readmission or mortality., Conclusions: Our experience from two North American centers indicates that, in experienced hands, postoperative outcomes after uniportal and multiportal VATS segmentectomy are comparable., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-22-780/coif). The authors have no conflicts of interest to declare., (2023 Journal of Thoracic Disease. All rights reserved.)

Background: Acute Respiratory Distress Syndrome (ARDS) as defined by the Berlin definition has an approximate mortality rate of 40% and no curative treatment. Mutliple therapies have been studied to reduce mortality but only neuromuscular blocking agents show potential benefits on mortality and other complications of ARDS., Objective: This review aimed to investigate the efficacy of neuromuscular blockers in ARDS METHODS: Medline, Embase, Cochrane Central and Web of Science were queried on October 1st, 2021. Randomized clinical trials comparing neuromuscular blockers to any comparator in treating ARDS were included. Primary outcome was mortality. Secondary outcomes were ventilator-free days, intensive care (ICU) length of stay (LOS) and complications. Results between sedation levels were examined with a Bayesian Network for Meta-analysis method., Results: We included 6 trials compiling a total of 1557 patients. Neuromuscular blockers compared to any comparator in treating ARDS showed a reduction in mortality (RR 0.79 [95% CI, 0.62 to 0.99]). No difference in ventilator-free days (MD 0.68 [95% CI, -0.50 to 1.85]) or ICU LOS (MD 0.77 [95% CI, -2.99 to 4.54]) were found. A Bayesian Network Meta-analysis yielded no difference in mortality when using light sedation compared to heavy sedation in ARDS. (OR 0.58 [95% CrI, 0.07 to 4.46].) CONCLUSION: Neuromuscular blockers safely reduce mortality. Light sedation potentially has a similar impact on mortality as heavy sedation that carries some burden. A non-inferiority trial comparing both sedation levels may be warranted considering the added value of light sedation., Competing Interests: Declaration of Competing Interest No authors must declare any conflict of interest., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Venous thromboembolic events (VTE) are frequent complications in hospitalized patients and a leading cause of preventable death in hospital. Pharmacologic prophylaxis is a standard of care to prevent VTE in patients at risk, the additional value of intermittent pneumatic compression (IPC) is uncertain. We aimed to evaluate the efficacy of adding IPC to pharmacologic prophylaxis to prevent VTE in hospitalized adults., Data Sources: We searched the Cochrane Central Register of Controlled Trials, Embase, MEDLINE, Cumulative Index to Nursing and Allied Health Literature, ClinicalTrials.gov, and the International Clinical Trials Registry Platform from inception to July 2022., Study Selection: We included randomized controlled trials comparing the use of IPC in addition to pharmacological thromboprophylaxis to pharmacological thromboprophylaxis alone in hospitalized adults., Data Extraction: Meta-analyses were performed to calculate risk ratio (RR) of VTE, deep venous thrombosis (DVT), and pulmonary embolism (PE). We assessed the risk of bias using the Cochrane Risk of Bias Tool for Randomized Trials, Version 2 and the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation approach., Data Synthesis: We included 17 trials enrolling 8,796 participants. The IPC was mostly applied up to the thigh and pharmacological thromboprophylaxis was primarily low-molecular-weight heparin. Adjunctive IPC was associated with a decreased risk of VTE (15 trials, RR = 0.53; 95% CI [0.35-0.81]) and DVT (14 trials, RR = 0.52; 95% CI [0.33-0.81]) but not PE (seven trials, RR = 0.73; 95% CI [0.32-1.68]). The quality of evidence was graded low, downgraded by risk of bias and inconsistency. Moderate and very low-quality evidence, respectively, suggests that adjunctive IPC is unlikely to change the risk of all-cause mortality or adverse events. Subgroup analyses indicate a more evident apparent benefit in industry-funded trials., Conclusions: Results indicate low-quality evidence underpinning the additional use of IPC to pharmacological thromboprophylaxis for prevention of VTE and DVT. Further large high-quality randomized trials are warranted to support its use and to identify patient subgroups for whom it could be beneficial., Competing Interests: Dr. Duval received a scholarship from the Fondation du CHU de Québec and the Université Laval. The remaining authors have disclosed that they do not have any potential conflicts of interest., (Copyright © 2022 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the Society of Critical Care Medicine.)

Background: An estimated 11 million burn injuries with medical attention occur every year worldwide. Although potentially deadly, burn injuries are now considered a chronic disease with multiple lifetime physical and psychological sequelae. However, it remains unclear how these events affect patients' utility scores. We aimed to conduct a systematic review to summarize the utility scores of burn injury survivors., Methods: We conducted on March 18 th , 2020 a systematic review of the published literature using a search strategy designed in collaboration with a research librarian. Our search strategy aimed to identify studies that provided burn injury survivors' utility scores via a standardized indirect instrument., Results: We identified 15 studies that reported burn injury survivors' utility scores. Most studies used the EQ-5D instruments to assess patients' utility scores. Results varied substantially between studies, ranging from a low of 0.06 to a high of 0.972. Our review identified two key trends. First, utility scores seem to be negatively correlated with the severity of the burn injury. Second, utility scores in adults tend to increase in function of the time since injury., Conclusion: Unfortunately, due to differences in study design and settings, patient populations and instruments used to assess patients' utility scores, we were unable to combine all study results into a single value. In spite of this limit, results we identified support previous trends identified by others regarding the relationship between utility scores and the burn injury severity and/or the time since injury., (Copyright © 2021 Elsevier Ltd and ISBI. All rights reserved.)

Objective: A retrospective immunohistochemical study of parotid gland lesions was designed to evaluate the diagnostic and prognostic value of the proliferating cell nuclear antigen (PCNA) and Ki-67 with monoclonal antibodies PC 10 and MIB-1, respectively., Study Design: Tissue samples comprised normal parotid gland (N, n = 10), chronic sialadenitis (CS, n = 8), Warthin's tumor (W, n = 10), benign pleomorphic adenoma (BPA, n = 8), mucoepidermoid carcinoma (MEC, n = 13), carcinoma in pleomorphic adenoma (CPA, n = 8) and adenoid cystic carcinoma (ACC, n = 12). The morphometric parameters for PCNA and MIB-1 comprised the PI and MI labelling indices (the numerical percentage of positive nuclei), NAP and NAM (the numerical density of positive nuclei), and NPI and NMI (volume corrected index)., Results: The values of MIB-1 parameters increased progressively in benign lesions in comparison with the N group and in malignant neoplasms in comparison with nonneoplastic groups and benign lesions. Values for all parameters in BPA were significantly lower than those in malignant groups. Spearman rank correlation analysis showed a highly positive correlation between the morphometric parameters and severity of the lesions. The mean values of MI and NMI were significantly higher in patients who died of the malignant tumors than in those who survived. The same quantitative parameters for PCNA did not differ significantly from those obtained for MIB-1 and showed similar trends., Conclusion: PCNA and MIB-1 indices are reliable markers for discriminating between benign and malignant tumors of the parotid gland, and the parameters PI, MI, NPI and NMI may have prognostic applications.

The present study uses morphometric techniques to assess whether altered differentiation patterns exist in PPM which might reflect its premalignant status. Samples were obtained from resected malignant lesions of large bowels of 10 Chinese patients. Normal (N) samples were biopsied from the margins of each resected large bowel. Potentially premalignant (PPM) mucosae were obtained from within 2 cm of the margins of the malignant lesions. Tissues were processed for histological examination and using strict criteria, colorectal crypts were divided into basal (B), intermediate (I) and surface (S) segments. Interactive digitisation of sections from each group was used to generate the following morphometric parameters in each segment: nuclear profile circularity indices (NSF and NCI); nuclear numerical density (NA and NV); the degree of deviation of the major nuclear axis in relation to the epithelial-connective junction (AGDMAX); cell height (CH); the distance between nuclear apex to cell apex (DNACA); the distance between cell base to nuclear apex (DCBNA); stratification index (SI)--the ratio of DCBNA and CH; and the volume density of mucous vacuoles in the reference epithelium (VVMV,EP). In comparisons of different segments within groups, the nuclei at the S segment of N and PPM crypts were more irregular and less circular in shape than nuclei from other segments. There was a shift of nuclear profile shape (NSF and NCI) from circular to ellipsiodal between B and S segments. In comparisons of similar segments between groups, no significant nuclear shape changes were detected in nuclei of PPM crypts when compared with nuclei in similar segments of N crypts and the pattern of nuclear shape alterations resembled those of normal crypts. In comparisons of different segments within groups of N and PPM crypts, AGDMAX, DNACA, DCBNA, CH and SI parameters demonstrated that epithelial cells at the I segments have more centrally positioned nuclei with the tallest epithelial height when compared with epithelial cells in other segments of both crypts. In B segments, nuclear NA and NV were almost double those of other segments in both N and PPM crypts, with marked reductions in these parameters between B and I segments. VVMV,EP was significantly highest in the I segment and significantly lowest in the S segment of both groups. Both N and PPM crypts showed similar trends in VVMV,EP within the crypt segments but when comparing similar segments between both crypts, a significant difference was detected only between S segments. The alterations of nuclear shape and packing densities, orientation and mucous content in N crypts were similarly expressed in PPM crypts and distinct differences in numerical density (NV) and stratification index existed in crypts between these two groups when comparing similar segments. All values in PPM were consistently lower when compared with N crypts. These preliminary observations may represent a subtly altered state of cellular differentiation in PPM which may be a reflection of early preneoplastic transformation.

The aim of the study was to determine the expressions and effects of KGF and bFGF of FGF superfamily in oral mucosa. The mRNA transcriptional levels of bFGF and KGF in dysplasia (DYS) and squamous cell carcinoma (SCC) of buccal mucosa were observed and evaluated by in situ hybridization method. The results showed that bFGF and KGF mRNA were expressed by the mesenchymal cells in both DYS and SCC groups, but not in any of the epithelial cells. The positive reactions were located in fibroblasts, endothelial cells and some of the chronic inflammatory cells. There is an increasing mRNA transcriptional level in SCC than in DYS. The results indicated that bFGF and KGF may not only enhance the neovascularization and formation of stroma by autocrine and paracrine action, but also involved in the growth of neoplastic cells.

To identify the cell types which produce BMP and TGF-beta during fracture healing and to elucidate the interactions between BMP and TGF-beta in regulating cell proliferation and differentiation at various stages, an experimental model of fracture healing in the rabbit mandible was established and the expression of BMP-2 and TGF-beta 1 mRNA was studied at different healing stages by in situ hybridization. The results showed that undifferentiated mesenchymal cells, differentiating osteoblasts and chondroblasts, had higher levels of BMP-2 mRNA at the stage of intramembranous bone formation and early chondrogenesis, while the level of TGF-beta 1 mRNA was higher in chondrocytes and active differentiated osteoblasts during chondrogenesis and endochondral ossification, respectively. We conclude that BMP-2 expression was correlated with the differentiation of mesenchymal cells into osteoblasts and chondrocytes. TGF-beta 1 mRNA expression was closely associated with the active synthetic stage of osteoblasts and chondrocytes. These observations suggest that both BMP and TGF-beta are involved in the regulation of fracture healing. BMP may play an important role in bone induction and early chondrogenesis, while TGF-beta regulates the proliferation and active synthetic ability of chondrocytes and osteoblasts.

Previous studies have suggested that alterations of the p53 gene are the most common genetic abnormality in human cancer. The aims of the present study were to evaluate p53 protein (p53P) immunostaining in adenoid cystic carcinoma (ACC) of the salivary gland and to correlate the expression with patient survival. A total of 27 cases of ACC in the parotid gland (n = 12) and the minor palatine glands (n = 15) were studied, with ten cases each of normal parotid and palatine glands as non-neoplastic controls. Staining was performed with mouse monoclonal antibody DO-7 against p53 (Dako, USA) using the ABC method. Stained nuclei irrespective of intensity or frequency were considered as positive. The frequency of positive nuclei was evaluated as the p53P index (p53PI), the percentage of the total nuclei in the reference epithelium. Clinical survival data were available for patients for periods up to 156 months. Our data showed that no normal tissues showed immunoreactivity with p53P in their nuclei. Thirteen of 15 (87%) cases of palatal and two of 12 (17%) cases of parotid neoplasms stained with p53P and the p53PI ranged from 0.01 to 10%. The number of p53P positive tumors was significantly higher in palatal than in parotid neoplasms, suggesting that palatal ACCs may be more aggressive in comparison with parotid ACCs. Our data also showed that the number of p53P positive tumors was significantly increased in patients who died of tumors than in patients with no evidence of disease at the end of the follow-up period between 60 to 156 months. These results suggest that p53P may be involved in the development of salivary gland ACCs and that p53P analysis may be a useful indicator of poor prognosis.

Immunoreactivity of proliferating cell nuclear antigen (PCNA) was assessed in formalin-fixed, paraffin-embedded sections from human normal parotid gland (N; n = 12), chronic sialadenitis (CS; n = 8), Warthin's tumour (W; n = 10), benign pleomorphic adenoma (BPA; n = 11), mucoepidermoid carcinoma (MEC; n = 14), carcinoma in pleomorphic adenoma (CPA; n = 10) and adenoid cystic carcinoma (ACC; n = 12) of the parotid gland, using the monoclonal antibody PC 10. The morphometric parameters measured comprised PCNA labelling induces (PI = the numerical percentage of PCNA positive nuclei) and volume densities of PCNA positive nuclei(VV, PEP = the relative volume of positive nuclei per unit volume of reference epithelium). All parameters were expressed in relation to total positive, as well as to strongly- and weakly-positive nuclei. In general, the values of PCNA parameters increased progressively in benign lesions in comparison with the N group, and in malignant neoplasms in comparison with non-neoplastic groups and benign lesions. The strongly-positive parameters showed more statistically significant differences than weakly-positive ones, suggesting that weakly-stained nuclei may include some non-cycling cells and, therefore, that weakly-positive parameters may not be reliable proliferation markers. Values for all parameters in CPA were significantly higher than those in BPA, suggesting that these parameters may be used as diagnostic discriminators. Spearman rank correlation analysis showed a highly positive correlation between the morphometric parameters and the severity of the lesions. Furthermore, the mean values of PISP were significantly higher in patients who died of the malignant tumours than in those patients who survived. Our results indicate that PCNA indices might be useful markers for discriminating between benign (BPA) and malignant tumours of the parotid gland and that the parameter PISP may have prognostic applications.

The increase in nuclear cytoplasmic (N/C) ratio is one of the features of cellular atypia which is used in the histopathological assessment of premalignant lesions of the oral mucosa. Since this feature is readily quantifiable using morphometry, we have analysed both N/C and nuclear volume densities in basal and spinous cells from human cheek lesions with and without malignant potential in order to ascertain the validity of this parameter as a predictor. Using a strictly standardised sampling procedure, measurements of cellular and nuclear areas of basal and spinous cells from normal and pathological human cheek mucosa were made on haematoxylin and eosin-stained sections using a VIDAS image analyser. Cases examined comprised fibrous hyperplasia (FH), traumatic inflammation (IF), benign hyperkeratosis (HK), lichen planus (LI), leukoplakia with dysplasia (DYS), squamous cell papilloma (PP), dysplastic epithelium from the edges adjacent to invasive carcinoma (CE) and islands from invasive squamous cell carcinoma (CI). In basal cells, N/C ratios and nuclear volume densities were lower than values obtained for the normal controls. In spinous cells, these parameters were elevated in the potentially premalignant lesions (DYS, CE) as well as in CI but values were similarly elevated in FH, IF, HK and PP, lesions which appear to have no malignant potential. The N/C ratio is of no value as a predictor of malignant potential in basal or spinous cells from cheek lesions. The putative increase in N/C which has been previously described qualitatively is probably due to increased nuclear hyperchromatism, which may provide an illusory increase in relative nuclear size at the expense of the cytoplasm.

Quantification of silver-stained nucleolar organiser regions (AgNORs) in paraffin sections may provide clues about the proliferation and differentiation in normal and neoplastic tissues. The aim of the present investigation was to determine whether AgNOR quantification could provide useful data about proliferation in the different segments of the normal human colorectal crypt. Samples of histologically 'normal' large intestine (n = 8) were obtained from colorectal cancer resections at a distance of > 5 cm from the tumour margins and were routinely processed for paraffin embedding using strictly standardised procedures. Sections were cut and stained with a one-stage silver colloid impregnation technique. The longitudinally sectioned crypts were divided into proliferative (P), intermediate (I) and surface (S) segments using strict criteria. Clearly defined AgNORs, which appeared as black dots within the nuclear profile, were quantified from each segment for volume density (Vv) and number per unit area (NA) estimates using traditional point-counting techniques. A 1-way analysis of variance followed by Scheffe's test indicated significant progressive reductions of AgNOR Vv and NA from P to S segments. Our data suggest that both volume and frequency of AgNORs may be related to cellular proliferation since both parameters are highest in the P segment. The further exploitation of stereological tools in conjunction with AgNOR staining may be valuable in assessing normal differentiation and proliferation patterns and in predicting the biological behaviour of neoplastic tissues in which increased proliferation is a feature.

The present study investigates relationships between neovascularisation and PCNA cell proliferation markers in different pathological lesions of the oral cheek mucosa. All specimens were fixed in 10% formalin and routinely processed for histology. Six normal (N) samples were taken from resection margins of benign lesions. The pathological lesions consisted of chronic inflammation (n = 10), lichen planus (n = 7), fibrous hyperplasia (n = 11), dysplasia (n = 5), squamous cell carcinoma (n = 22) and epithelium adjacent to carcinoma (n = 6). Adjacent 5 microns sections were stained with monoclonal antibodies against vimentin (clone no. V9) for identification of stromal blood vessels and against proliferating nuclear antigen (PCNA/PC10) using ABC immunoperoxidase techniques. Point counting was used to obtain the primary morphometric data using a Zeiss VIDAS image analyser. No attempt was made to classify the different types of blood vessels. The morphometric blood vessel parameters estimated were volume density, number per unit area, length per unit volume and mean transverse sectional area. PCNA indices were determined by estimating the percentage frequency of PCNA positive nuclei in basal and spinous strata. Generally, there were significant increases in all PCNA indices and blood vessel parameters between the N group and the different pathological lesions. A highly positive correlation was detected between all PCNA indices and blood vessel parameters. These data suggest that increased vascularity and angiogenesis occur in support of actively proliferating and transforming oral epithelial cells in order to permit growth. PCNA indices and blood vessel parameters may have a potential application as diagnostic and prognostic indicators.

High-performance liquid chromatography has been applied to determination of modifier activity in alpha-lactalbumin (alpha-LA). An amino-bonded column separates uridine diphosphate (UDP) (product), UDPgalactose (substrate), and uridine monophosphate (UMP). From an aliquot of the same sample, a column for carbohydrate analysis separates lactose (the other product) and galactose-1,2-cyclic phosphate (Gal-c-P). Nucleotide peaks are detected by measurement of A262 and those of carbohydrate by 3H counting, the isotope originating from UDP-galactose-3H. A pH of 6.3 was taken as optimal for production of UDP since, at this level, the unwanted side reaction is minimized, by which UMP and Gal-c-P are formed. Thus, the conservation of substrate so effected may have contributed to an enhanced production of UDP. The reaction by which UDP and lactose are produced was linear for 120 min, as followed by UDP formation, but it continued to at least 300 min. Production of lactose was equivalent to that of UDP, when alpha-LA was the modifying protein. From a survey of seven other proteins, only lysozyme and ovalbumin showed ability to produce UDP. However, failure of the last two proteins to produce lactose indicates absence of modifier activity and demonstrates the need for monitoring both products.

We have analysed both the nuclear-cytoplasmic (N/C) ratio and nuclear volume densities (VVN) in defined strata from human hard palate lesions with and without malignant potential to determine the prognostic reliability and/or validity of this parameter. Measurements of cellular and nuclear areas of basal and spinous cells from normal (N) and pathological palatal epithelium were made on histological sections using an image analyser. The lesions comprised fibrous hyperplasia (FH), traumatic inflammation (INF), benign hyperkeratosis (HK), squamous cell papilloma (PP), dysplastic epithelium adjacent to invasive carcinoma (CE) and islands of invasive squamous cell carcinoma (CI). In basal cells, no significant differences were detected in comparisons of N/C and VVN between all pathological groups and the N control group. The mean value for CE was lower than that obtained for N. In spinous cells, the only statistically significant comparison was between IF and FH for both N/C and VVN. Both parameters were lower in CE than in N. Of all groups analysed except CI, the CE group is the only one likely to possess an increased malignant potential. The N/C ratio therefore seems to be of no value as a predictor of malignancy in palatal epithelial lesions.

Neovascularisation in tumours of different cell origins has been well documented qualitatively. In this report, we have assessed vascular architecture in different pathological lesions of the colorectum by quantifying blood vessel parameters in order to detect subtle morphological changes using objective methods. Colorectal tissue samples were obtained from resected large bowels containing malignant tumours. Biopsies were taken from defined sites in the resected specimen and were classified as normal (N), potentially premalignant mucosa (PPM), adenomatous polyp (P) and adenocarcinoma (ADCA). All tissues were fixed in modified Karnovsky's fixative for 4 hrs and postfixed in 1% OsO4 for 1 hr. Samples were processed for EM under standardized procedures and embedded in Epon. 0.5 microns semithin sections from five patients per group were stained with toluidine blue. A multistage systematic sampling procedure was adopted. The inner outlines of all blood vessels in the lamina propria (LP) were digitised using a Zeiss VIDAS Image Analyzer at a final magnification of x1,050. The area of the reference (LP) was also measured. No attempt was made to distinguish between the different types of vessel. The morphometric blood vessels parameters quantified were volume density (Vv), numerical density (NA), length density (LV) and mean transverse sectional area (A). Statistically significant differences in Vv and A were detected between all groups except between N and PPM and between P and ADCA. No significant differences in NA and LV were present in any group comparisons. The mean values of all parameters were the highest in ADCA.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

A monoclonal antibody raised against bone morphogenetic protein (BMP-McAb) has been used to demonstrate the presence of bone morphogenetic protein (BMP) in experimental fracture healing. Rabbit mandibles were fractured using standardized methods and left to heal for 3, 7, 14, 21 and 24 d, respectively. The avidin-biotin complex (ABC) method demonstrated an accumulation of positively stained primitive mesenchymal cells at the fracture site in the hematoma stage of bone repair. These cells appeared to undergo differentiation into positively-stained chondroblasts and osteoblasts during the phase of callus formation. Undifferentiated mesenchymal cells showed a high positive reactivity in the early post-fracture stages but a much lower reactivity during the remodelling phase. The results of our study suggest that bone inductive processes are accompanied by the presence of BMP in osteoprogenitor cells during fracture healing of the mandible and that BMP may play a significant role in osteogenesis during bone healing.

Patients with oral lichen planus lesions may represent a relatively high risk population for subsequent development of oral cancer. Little is known of the relative effects of chronic inflammation and the process of malignant transformation itself on the histological structure of transforming epithelia. We have assessed cellular and nuclear volumes in defined basal and spinous cells from normal buccal mucosa epithelium, from epithelium associated with a non-specific chronic inflammatory infiltrate and from lichen planus lesions. Normal (N) tissues were obtained from the margins of non-neoplastic buccal mucosa lesions. Inflammatory (INF) lesions were from areas of the buccal mucosa diagnosed clinically as traumatic irritation without ulceration, and lichen planus (LI) lesions were biopsied from areas exhibiting Wickham's striae. Basal and spinous epithelial cells from normal and pathological human buccal mucosa were measured on haematoxylin and eosin-stained sections imaged through a video camera using a Zeiss VIDAS analyser and from these measurements, nuclear (VN) and cellular (VCELL) volumes were determined. VN and VCELL derived for both basal and spinous strata were similar in N and INF groups but were almost doubled in the LI group. Comparisons between LI and all other groups were significantly elevated. The effects of the inflammatory infiltrate on the oral epithelium in lichen planus and in non-specific inflammation thus differ significantly. VN and VCELL may serve as potential discriminators between benign lesions and premalignant lichen planus.

Cylindric titanium implants treated with bovine bone morphogenetic protein (bBMP) (Group I) and with bovine serum albumin (BSA) (Group II) were implanted in the edentulous mandibles of 15 adult dogs. They were examined 1, 2, 4, 8, and 12 weeks after insertion of the implants by scanning electron microscopy (SEM). In all specimens from Group I, active bone formation had occurred between the implant and host bone, with a well-adapted fit between the implant and the newly formed bone 4 weeks after implantation. The surrounding bone was of normal structure by week 8. However, 3 months after implantation, fibrous tissue was consistently seen surrounding parts of the implants in Group II. The results of this study suggest that the implants treated with bBMP are capable of forming new bone of normal structure at a faster rate than BSA controls and that this new bone is closely adapted to the implant surface.

This study established a method for combining bovine bone morphogenetic protein (bBMP) with titanium and evaluated the early bone formation induced by the bBMP/titanium complex in edentulous dogs. Results showed newly formed bone within the interface bone 2 weeks after implantation and nearly complete osseointegration 4 weeks after implantation. Bone formed with the apical opening of the implant within 1 month. This study indicates that osseointegration can be enhanced by bBMP-bone induction. The apical opening of the implant may provide a site in which osteogenesis can occur with protection from implant stress before and after loading.

Differentiation of odontoblasts is important for dentin formation in tooth germs and mature teeth. Although previous reports have indicated that there may be a kind of inductive agent that could induce mesenchymal cells in dental pulps to differentiate into odontoblasts, and secrete dentin matrix, the primary inductive factor of odontoblasts has not been found. Bone morphogenetic protein (BMP), which induces the formation of cartilage and bone when implanted in muscle tissue, is found in dentin matrix. The relationship between the differentiation of odontoblasts and BMP was observed by means of immunohistochemical staining with monoclonal antibody (MAb) against BMP in dental pulp tissue and cell culture; [3H]thymidine incorporation; and measurement of alkaline phosphatase activity. The conclusions are: (1) BMP exists in odontoblasts, ameloblasts, and dentin matrix (the positive reaction in ameloblasts appeared earlier and remained stronger); (2) BMP promotes incorporation of [3H]thymidine and increases the activity of alkaline phosphatase in cultured dental pulp cells; (3) BMP-induced dental pulp cells in dental pulp tissue cultures differentiate from mesenchymal to odontoblast-like cells; and (4) BMP induces formation of osteodentin and tubular dentin when used as a dental capping agent of dogs' teeth. Bone morphogenetic protein plays an important role in differentiation of odontoblasts and might be one of the inductive agents of odontoblasts. Further investigations of BMP as a biologic dental capping agent are warranted.

This report describes the application of simple morphometric methods to generate quantitative data on nuclear size from tissue sections of normal, benign and malignant oral epithelium of the cheek. Measurements of nuclear areas of basal and spinous cells from cheek mucosa were made on haematoxylin and eosin-stained sections using a Zeiss VIDAS image analyser. The lesions examined comprised benign squamous cell papillomas and islands of cells from invasive squamous cell carcinomas. Normal control epithelium was obtained from the biopsy margins of non-neoplastic lesions. The nuclear areas (AN) were obtained by direct measurement whereas the nuclear diameters (DN) were determined automatically. In both basal and spinous strata, values for both these nuclear parameters were lowest in normal tissue and increased progressively through benign papillomas, with the highest values being found invariably in carcinomas. Statistically significant differences were detected between both normal and carcinoma and between papilloma and carcinoma. The morphometric parameters AN and DN are of value in distinguishing benign from malignant lesions of the human cheek.

Earlier, a sensitive turbidimetric method was reported (H.A. McKenzie and F.H. White, Jr. Biochem. Int. 14, 347-356, 1987), with which evidence was found for weak lysozyme-like activity in alpha-lactalbumin (alpha-LA) against Micrococcus luteus. Alternative methods have been developed for the further study of trace cell-lytic activity, and the results are compared with those of the turbidimetric technique. These methods involve (1) determination of weight loss from a suspension of bacterial cells after exposure to the protein under investigation, and (2) viability studies on the exposed cells. In addition, exposed and control cells were subjected to microscopic examination. Results from all studies were consistent with lysis of cells by alpha-LA as well as by lysozyme. Activities of alpha-LA from the three methods of assay, expressed as ratios to those of lysozyme, were 2.2-5.2 x 10(-5) (mean = 3.6 x 10(-5). The methods were assessed with respect to sources of error characteristic of each and to protein dose requirements for a specified level of cell killing. The turbidimetric approach remains useful for measuring cell-lytic activities as described here. However, caution is urged in its general use.

Quantifiable variations existing in the colorectal crypt during cellular differentiation were detected by using simple computer-aided morphometric techniques applied to routinely prepared H&E stained and semithin toluidine blue stained sections of normal colonic mucosa. Generally, most of the morphometric parameters including nuclear volume, nuclear volume weighted mean volume, cytoplasmic volume, cellular volume, nuclear axial ratio (a/b), mean nuclear diameter, nuclear shape factor (NSF) and nuclear maximum angle (Agmax) showed an increasing trend between basal and surface segments. Conversely, the nuclear-cytoplasmic (N/C) ratio, NSF and nuclear circularity index (NCI) decreased between these segments. Epithelial cells in the basal segment had the highest N/C ratio and the lowest cell volume due to their low volumes of cytoplasm. However, substantial increases of cytoplasmic volume occurred in the intermediate segment, thereby expanding the cell volume to 136% of that of the basal segment cell. Data for a/b, NSF, NCI and Agmax suggest that the epithelial nuclei were more ellipsoidal in shape and were aligned more perpendicular to the basement membrane as they reached the surface epithelium. Numerical densities for epithelial cell nuclei were highest in the basal segment, indicating more nuclear profiles at this region per unit area or volume. This also suggested that the basal segment was the active proliferating zone. Such observations agree with previously reported cell kinetic and autoradiographic studies.

Effects of calcium removal on the cell-clearing activity of alpha-lactalbumin (alpha-LA) and concomitant changes in conformational structure have been investigated as part of a continuing study of the activity found earlier [McKenzie, H.A. & White, F.H., Jr. (1987) Biochem. Int. 14, 347]. This activity is similar to that of lysozyme, whereby lysis of the bacterial cell wall is catalyzed. However, the specific activity of alpha-LA is on the order of 10(-6) that of lysozyme. Under conditions where activities of apo and native alpha-LA were approximately linear functions of the protein concentration, the maximal ratio of apo to native activity was 5.7:1, determined by comparison of second order velocity constants. The CD spectrum of apo alpha-LA is intermediate between that of the A state and the native protein. By NMR, the conformation of apo alpha-LA is similar to, but distinctly different from, that of the native protein. The apo form did not revert completely to the native state when Ca(II) was resupplied, consistent with a role for this cation in folding. It is suggested that the activity increase may result from a diminished constriction of the "cleft" region in alpha-LA.

Upon administration of pharmacological doses of estradiol to castrated guinea pigs, the secretory cells of the lateral prostate underwent hypertrophy which resulted from significant increases in nuclear and cytoplasmic volume. There were quantitative increases in the small highly electron-dense granules and multivesicular bodies when compared with the castrated control. The dramatic increase in the number of highly electron-dense granules probably occurred at the expense of the low electron-dense granules. The average size of the condensing granules and mitochondria decreased significantly after estradiol administration. However, significant increase in the number of mitochondria was detected when compared with the castrated control. Ultrastructural data revealed no significant changes in the absolute dimensions of granular endoplasmic reticulum or of the Golgi complex, suggesting that estradiol exerted no significant stimulatory effects on these organelles. Pharmacological doses of estrogen appear to regulate the expression of secretory granules and multivesicular bodies in the lateral prostate of castrated guinea pigs.

The glandular epithelium of the lateral prostate of the guinea pig was described within the framework of a morphometric model in terms of relative densities and absolute dimensions. A combination of direct measurement and point and intersection counting techniques was used. The quantitative data generated in the intact animals were compared with those of castrated controls. Castration was accompanied by a significant decrease in height of the glandular epithelium and in sizes of secretory and basal cells and their corresponding nuclei. On a per cell basis, significant decreases in total volume and surface area of granular endoplasmic reticulum were detected after castration. This was accompanied by a significant reduction in the total volume of Golgi cisternae. The total volume, surface area, and number of highly electron-dense and clear granules decreased significantly compared with the intact control animals. However, no significant changes in these parameters of low electron-dense granules were found. Significant reductions in the total volume and surface area of condensing granules, lysosomes, and mitochondria, but not their number, were detected. The average sizes of condensing granules, secretory granules, lysosomes, and mitochondria were decreased significantly after castration. The present study showed that the alterations in the secretory function of the secretory cells of the lateral prostate was reflected by the quantitative changes in granular endoplasmic reticulum, Golgi complexes, and secretory granules on a per cell basis. The data generated in the present study will serve as a baseline for further studies of the lateral prostate of the guinea pig.

As an approach to learning more about structure-forming processes in chicken egg white lysozyme, the reduced protein was studied in the presence of methanol, 2-chloroethanol, trifluoroethanol, and sodium dodecyl sulfate, at various concentrations in aqueous solution. The mixtures were subjected to gel filtration chromatography, with circular dichroism (CD) examination of the resulting polymers and monomers. Changes in CD behavior, indicating development of ordered structure, were seen to be associated only with polymer formation. Contributing to these changes were increases in beta structure as well as alpha-helix. Since the solutes studied are known as helix formers, it is suggested that studies on many proteins, carried out in the presence of these and other structure-modifying solutes, may have been complicated by formation of beta structure as well as by polymerization. The reduced monomer formed no structure in the hydrophobic environment afforded by these solutes, but only randomized further. Thus, hydrophobic interactions may be of no significance to lysozyme chain folding in its early stages. As an alternative, the long range interactions stabilized by native tertiary cross links may be critical for the transition to native secondary structure.

People with an "internal" locus of control believe that ability and effort are important factors in affecting what happens to them, whereas those with an "external" locus of control believe that this is more a matter of luck or fate. Patients whose oral health was rated as being "good" scored in a more internal fashion on a locus of control questionnaire than patients whose oral health was "moderate" or "poor," suggesting that locus of control beliefs are important in the design of preventive programs on a personalized basis.

One of the features of epithelial dysplasia at the histological level is known as "loss of cellular adherence" in which adjacent epithelial cells appear more widely separated from each other than in normal tissues. In this study we examine the effects of the carcinogen DMBA on the epithelium of the hamster cheek-pouch with particular emphasis on the dimensions of the intercellular spaces. DMBA-induced lesions were processed for electron microscopy and assigned to hyperplasia, dysplasia and carcinoma groups, using defined criteria on toluidine blue-stained 1 micron Araldite sections. Untreated pouches were used as a control. At the light-microscopical level, intercellular spaces in hyperplastic epithelium appeared similar to those present in untreated tissue but increased progressively in dysplastic and carcinomatous lesions. Spaces were generally wider between basal and spinous cells than between granular cells, although wide variations were observed between tissue blocks demonstrating similar histological features and also within adjacent areas of the same block. At the ultrastructural level, untreated and hyperplastic tissue showed only occasional focal separations of adjacent plasma membranes; these spaces were more frequent between cells of lower strata. In sections from dysplasias and carcinomas, spaces were always extensive and were occupied by numerous villous or foliate membrane-bound cytoplasmic extensions. These were often attached to each other by desmosomes of apparently normal morphology but of a lower frequency than in untreated epithelium. The increased epithelial separation as indicated by the increased intercellular spaces during chemical carcinogenesis may be a result of any or all of the following factors: desmosomal disruption or their failure to develop; the production of cell-surface molecules which are less adhesive; inflammatory oedema and direct alterations on intercellular junctions and cell-surface components by infiltrating inflammatory cells.

Kidneys were cultured for leptospires and blood was collected for leptospiral serologic examination from 306 cattle slaughtered in Florida during June, July, and August 1980. Leptospires were found in 82(36%) of 226 otherwise bacterial-free cultures. Forty-five isolates were identified as Leptospira interrogans serovar hardjo, 3 as serovar balcanica, and 3 as serovar pomona. Leptospiral antibodies were found in 218 (71%) of the cattle. Serum titers to hardjo were found in 162 cattle (53%) and to pomona in 28 (9%). Low titers to tarassovi were found in 14 cattle (4.5%).

Isolated cells constitute a favourable experimental model for the pathologist interested in ultrastructural morphometry. A particular advantage is that the same sampling regime may be appropriate for both normal and pathologically-altered material. Often this is not the case with other model systems. This report reviews alternative methodologies for analysing isolated cells, including free cells and dissociated cells in culture. We begin by attempting to define problems of more general concern: preparative techniques, methods of sampling, selection of stereological parameters and possible sources of error. A generalised morphometric model for isolated cells is followed by descriptions of models devised for specific cell types, notably mononuclear phagocytes and cells of the lymphocyte family. Typical results obtained by stereological analyses of these models are presented.

Lesions produced by topical application of 0.5 per cent. DMBA to the hamster cheek pouch epithelium were classified as hyperplasia, dysplasia and carcinoma groups using strict histological criteria. Untreated epithelium served as a control. Tissue samples from five animals in each group were processed for electron microscopy and electron micrographs from the epithelial-connective tissue junction were obtained from 5 blocks per animal. The micrographs were subjected to stereological intersection counting to determine the relative surface (SSLD, BM) of lamina densa which was in normal relationship to the basal cell plasma membranes. Quantitative results indicated a progressive loss of lamina densa during carcinogenesis and this was accompanied by the extrusion of pseudopodia from the basal cells through the gaps. The pseudopodia were frequently related to peripheral cytoplasmic microfilaments. Quantitative data confirmed the progressive nature of this loss, with values for SSLD,BM being of the order of 98 per cent., 88 per cent., 76 per cent, and 42 per cent. for normal epithelium and for the hyperplastic, dysplastic and carcinomatous lesions respectively. The loss of lamina densa is discussed in relation to the specificity of the response and to the development of features indicative of motility in transforming cells.

The present report describes quantitative studies of mitochondria from stratified squamous epithelial cells from hamster cheek pouch mucosa in differentiating compartments. Mucosa was processed for electron microscopy and, using strict sampling procedures, electron micrographs of epithelium from defined basal, spinous and granular strata were acquired. Using stereological and other morphometric methods, the volume density, numerical density and volume-to-surface ratio of mitochondria were estimated in each cellular layer, and these data were transformed into absolute values characterising the average cell in these layers. The results suggest that both volumetric and numerical densities of mitochondria decreased progressively during epithelial differentiation; conversely, the total volume and number of mitochondria present in granular cells were consistently higher than in basal cells, as was the volume of individual mitochondria. These quantitative changes may reflect functional alterations in the metabolism of epithelial cells during differentiation and provide a base line for further work on experimental epithelial biology and pathology.

Desmosomes function as intercellular attachment devices. In keratinised epithelia, squames are shed from the surface and these are replaced by less differentiated cells of the basal or parabasal layers, which migrate progressively towards the surface. In order to perform these migratory activities, cellular movement must occur, with the implication that cells must be able to make and break their desmosomal attachments. The present study investigates desmosomal ultrastructure with the objective of suggesting mechanisms by which desmosomes are altered during differentiation. The majority of desmosomes in basal, spinous and granular layers were similar in morphology, with differences being quantitative rather than qualitative. Desmosomes appeared to be more frequent and of smaller dimensions in granular cells when compared with those present on cells from lower strata. Upon keratinisation, desmosomal cytoplasmic structural specialisations disappeared and the intercellular contact layer became more prominent. A number of features which might represent desmosomal formation or synthesis were observed in nucleated cellular layers. These included an apparent budding or fusing of attachment plaques from existing desmosomes. Asymmetrical attachment plaques were prevalent with a markedly reduced number of tonofilaments associated with one plaque or an attachment plaque which was generally or locally reduced in electron density. Other appearances suggested that de novo desmosomal formation occurred as a result of the production of either single or paired attachment plaques, often containing fine filaments extending for a short distance into the cytoplasm. In view of the increased frequency of desmosomes in granular cells, the majority of these desmosomal abnormalities may represent synthetic rather than degradative activities.

Nineteen 9-week-old brown pelicans (Pelecanus occidentalis), obtained from a colony in Vero Beach, Florida, containing environmentally acquired p,p'-DDE residues, were subjected to a food deprivation experiment. Samples of brain, liver, muscle, and fat taken after one and two week periods of starvation indicated that starved birds contained significantly greated residue levels in fat compared to non-starved controls. Such differences were not observed in residues in the other tissues. The significance of these findings is discussed in relation to the biology of brown pelicans.

The present study was designed to establish whether there are changes in hemidesmosomal distribution during defined stages of chemical carcinogenesis in hamster cheek-pouch epithelium. 0.5% DMBA in liquid paraffin was applied thrice weekly to hamster pouches and tissue samples were obtained at regular intervals and assigned to hyperplastic, dysplastic and carcinomatous groups on the basis of histological criteria. Untreated pouches served as controls. Following a strict sampling regime, electron micrographs were obtained from the epithelial-connective tissue junction and, using stereological intersection counting, the relative surface area of basal plasma membrane (BPM) occupied by hemidesmosomes was estimated. In normal epithelium 40% of the BPM is occupied by hemidesmosomes. During carcinogenesis, values decrease progressively and significantly to 35% in hyperplasia, 28% in dysplasia and 13% in carcinoma. A decrease in the relative area of hemidesmosomes would therefore appear to contribute to the increased motility of epithelial cells during a connective-tissue invasion and cellular metastasis.

The present report describes the use of stereological procedures to evaluate the volume of tonofibrils present in defined epithelial strata undergoing differentiation. Hamster cheek pouch epithelium was processed for electron microscopy and, following strict sampling procedures, micrographs were obtained from basal, spinous and granular layers. Using stereological point counting techniques, the volume density of tonofibrils present in unit volume of epithelial cytoplasm was determined for each layer. From previously determined estimates of cytoplasmic volume in this tissue, it was possible to calculate the absolute volume of tonofibrils present in the 'average' epithelial cell of each layer. The results describe essentially similar volume density data for each of the layers investigated. However, estimates of tonofibril volume in the 'average' cell increase more than threefold between basal and granular layers. It is concluded that as the epithelial cell differentiates through spinous and granular strata, synthesis of tonofilaments may occur.