Simulation of schoolyard's microclimate and human thermal comfort under Mediterranean climate conditions: effects of trees and green structures.

The present study explores the effects on microclimate parameters and on heat stress conditions of the bioclimatic redevelopment of an urban schoolyard based mainly on inserting shading canopies and replacing hard surfaces with green cover. This included the use of the recent version of the microclimate model ENVI-met (V4), first validated using experimental data and then later applied to different case studies in schoolgrounds of Volos, a coastal city in central Greece under Mediterranean type climate. The simulation of the existing yard condition showed that the values of the biometorological index PET (physiologically equivalent temperature, in °C), were within the range of the thermal sensation class of extreme heat stress (> 41 °C) from early morning, while at midday 80.5% of the yard area was within the range of the above class. With the implementation of the redesign proposal, 69.9% of the yard area was improved by two or three PET scale classes, helping to improve the microclimate in 82% of the total area of the courtyard. Tree canopies reduced the direct incident radiation more than 90%, reduced Tmrt and PET index up to 31 °C and 19 °C, respectively, and the surface ground temperatures of wet grass and hard surfaces more than 20 °C and 14 °C, respectively.

Microclimatic effects of planted hydroponic structures in urban environment: measurements and simulations.

The objectives of this effort was to study the effect of vertical (green wall) and horizontal (pergola) green structures on the microclimate conditions of the building surroundings and estimate the thermal perception and heat stress conditions near the two structures. The experimental data were used to validate the results simulated by the recent version (V4.0 preview III) of ENVI-met software which was used to simulate the effect of different design parameters of a pergola and a green façade on microclimate and heat stress conditions. Further aim is to use these results for better design of green structures. The microclimate measurements were carried out in real scale structures (hydroponic pergola and hydroponic green wall) at the Kostakii Campus of the Technological Education Institute of Epirus (Arta, Greece). The validation results showed a very good agreement between measured and simulated values of air temperature, with Tair,sim = 0.98 Tair,meas in the Empty atrium and Tair,sim = 0.99 Tair,meas in the Atrium with pergola, with a determination coefficient R 2 of 0.98 and 0.93, respectively. The model was used to predict the effects of green structures on air temperature (Tair), relative humidity (RH), and mean radiant temperature (Tmrt). The output values of these parameters were used as input data in the RayMan pro (V 2.1) model for estimating the physiologically equivalent temperature (PET) of different case scenarios. The average daytime value of simulated air temperature in the atrium for the case without and with pergola during three different days was 29.2 and 28.9 °C while the corresponding measured values were 29.7 and 29.2 °C. The results showed that compared to the case with no pergola in the atrium, covering 100% the atrium area with a planted pergola reduced at the hottest part of the day Tmrt and PET values by 29.4 and 17.9 °C, respectively. Although the values of air temperature (measured and simulated) were not greatly affected by the presence of a green wall, the most important effect of green wall to the building wall is the reduction of solar radiation behind the green wall. This reduction leads to a significant reduction (about 8 °C) of building surface temperature behind the green wall and accordingly to a reduction of the energy load of the building.

Evaluation of thermal perception in schoolyards under Mediterranean climate conditions.

The aim of this paper was to study qualitatively and quantitatively the thermal perception and corresponding heat stress conditions that prevail in two schoolyards in a coastal city in central Greece. For this purpose, meteorological parameters (i.e., wind speed, temperature, relative humidity, solar radiation) were recorded at 70 and 55 measuring points in the schoolyards, from 14:00 to 15:30 local time, during May and June of 2011. The measuring points were distributed so as to get measurements at points (a) directly exposed to the sun, (b) under the shadow of trees and building structures, and (c) near building structures. Cluster analysis was applied to group observations and revealed places that are microclimatically homogeneous. Thermal perception and heat stress conditions were assessed by means of the physiologically equivalent temperature (PET, °C), and the results are presented in relevant charts. The impact of material's albedo, radiation's reflection by structures and obstacles, and different tree species on thermal perception and heat stress conditions was also assessed. The analysis showed that trees triggered a reduction of incident solar radiation that ranged between 79 and 94 % depending on tree's species, crown dimension, tree height, and leaf area. PET values were mainly affected by solar radiation and wind speed. Trees caused a reduction of up to 37 % in PET values, while a 1-m s(-1) increase in wind speed triggered a reduction of 3.7-5.0 °C in PET value. The effective shading area in the two schoolyards was small, being 27.5 and 11 %. The results of this study could be exploited by urban planning managers when designing or improving the outdoor environment of a school complex.

Study of heat-stress levels in naturally ventilated sheep barns during heat waves: development and assessment of regression models.

It is well documented that heat-stress burdens sheep welfare and productivity. Peak heat-stress levels are observed when high temperatures prevail, i.e. during heat waves; however, continuous measurements inside livestock buildings are not usually available for long periods so as to study the variation of summer heat-stress levels for several years, especially during extreme hot weather. Α methodology to develop a long time series of summer temperature and relative humidity inside naturally ventilated sheep barns is proposed. The accuracy and the transferability of the developed linear regression models were verified. Temperature Humidity Index (THI) was used to assess sheep's potential heat-stress. Τhe variation of THI inside a barn during heat wave and non-heat wave days was examined, and the results were comparatively assessed. The analysis showed that sheep were exposed to moderate, severe, and extreme severe heat-stress in 10, 21 and 66 % of hours, respectively, during heat wave days, while the corresponding values during non-heat wave days were 14, 33 and 43 %, respectively. The heat load on sheep was much higher during heat wave events than during non-heat wave periods. Additionally, based on the averaged diurnal variation of THI, it was concluded that extreme severe heat-stress conditions were prevailing between 1000 and 2400 hours local time during heat wave days. Cool off night periods were never and extremely rarely detected during heat wave and non-heat wave days, respectively.

The role of ThinPrep cytology in the investigation of ki-67 index, p53 and HER-2 detection in fine-needle aspirates of breast tumors.

PURPOSE: The aim of the current study was to compare the immunocytochemical expression of ki-67, HER-2 and p53 on ThinPrep (TP)-processed smears, obtained by preoperative fine-needle aspiration (FNA) biopsies from primary breast carcinoma with the immunohistochemical results obtained on the corresponding surgical samples. METHODS: FNA biopsies were collected from 119 female patients during a 31-month period. Subsequently, these patients underwent surgical resection of the tumors. RESULTS: The overall accuracy (OA) of the TP cytology for ki-67, p53 and HER-2 expression was 96, 99 and 97%, respectively. There was a strong positive correlation between immunohistochemistry and immunocytochemistry results for ki-67 (Spearman's test 0.875) for p53 (Cramer's phi test 0.965) and HER-2 (Kendall's tau test 0.891). CONCLUSION: This pilot study demonstrates that it is possible to monitor multiple molecular markers by using the TP cytology. Sample collection and storage is simple and permits the assortment of the FNA sample for both morphologic diagnosis and ancillary studies. The accuracy of TP technique in the evaluation of ki-67, p53 and HER-2 expression is comparable to those of the histological evaluation, and could be of paramount importance for the preoperative planning of treatment.

Evaluation of apoptosis in classical Hodgkin's lymphoma comparing different methods.

PURPOSE: Apoptosis is a type of programmed cell death (PCD) with specific morphologic changes in the dying cell. Since classical Hodgkin's lymphoma (cHL) is characterised by abnormalities in the apoptotic pathways, apoptosis may play a central role in its pathogenesis. Our purpose was to estimate the apoptotic process in cases of cHL using 3 different, widely accepted methods, comparing their results as well as with those found in the literature. METHODS: Detection of apoptosis was performed in 76 cases of cHL, using morphological criteria, TUNEL assay (TUNEL apoptotic index; T-AI) and immunohistochemical detection of active caspase 3 (casp3-AI) on paraffin embedded sections. RESULTS: When both apoptotic (MA) and mummified (mummi-I) cells were evaluated by morphological apoptotic index (morph-AI), the median value was 10.3%, while for MA and mummi-I the results were 3.4% and 6%, respectively. T-AI and casp3-AI values were 10.9% and 1.9%, respectively. Morph-AI was significantly higher in the mixed cellularity (MC) subtype (p7equals;0.047rpar;, while MA was significantly higher in the male subgroup (p7equals;0.03). MA was strongly correlated with casp37horbar;AI (p=0.01). CONCLUSION: Detection of apoptosis has become an important parameter in understanding tumor pathology and in designing antitumor treatment. A combination of methods is proposed in order to estimate accurately this form of cell death.

Epithelial cell turnover, p53 and bcl-2 protein expression during oncogenesis of early and advanced gastric cancer in a Western population.

OBJECTIVES: To investigate epithelial cell turnover alterations, and p53, bcl-2 protein expression during development of early and advanced gastric cancer in a Western population. METHODS: We investigated cell apoptosis and proliferation rates, p53 and bcl-2 protein expression in 17 early and 34 advanced gastric carcinomas and in the adjacent non-dysplastic mucosa. Cell proliferation, p53 and bcl-2 expression were detected immunohistochemically using MIB-1, anti-p53 and anti-bcl-2 monoclonal antibodies. Apoptosis was measured by TUNEL. The rate of the positive stained cells (labelling index) was count using image analysis technique. RESULTS: No difference was observed of either apoptotic (10 vs. 11) or proliferation (35 vs. 25) index between early and advanced cancers. However, the apoptotic index was significantly higher in intestinal type advanced tumors. While both apoptotic and proliferation indices were significantly higher in tumors than in the adjacent mucosa, no difference was observed of either apoptotic (2 vs. 2) or proliferation (8 vs. 13) index between the tissues adjacent to early and advanced tumors. p53 protein expression was significantly higher in advanced cancers (7 vs. 5, p=0.001) and in the non-dysplastic tissue adjacent to advanced tumors (3.5 vs. 2, p=0.001). bcl-2 labelling index was significantly higher in the mucosa adjacent to advanced carcinomas (15 vs. 5, p=0.016) but this difference did not reach significance in the tumors (20 vs. 15, p=0.37). CONCLUSIONS: Our data indicate similar cell turnover during tumorigenesis of early and advanced cancer. p53 and bcl-2 protein accumulation is more intense in gastric mucosa adjacent to advanced tumors and p53 immunoreactivity peaks in advanced carcinomas.

Evaluation of immunohistochemical markers of germ cells' proliferation in the developing rat testis: a comparative study.

Germ cells' proliferation during testicular organogenesis in Wistar rat embryos and neonates [14.5, 18.5, 20.5 days post conception (dpc), birth (day 0), 1, 3, 5, 7 days post partum (dpp)] was evaluated via immunohistochemistry, using the PCNA and Ki-67 nuclear antibodies. Estimation of the reactive/total cell ratio, per visual field [labeIing index (LI)] was achieved using the Image Pro Plus Software. Immunostaining of the fetal testis, with both antibodies, revealed increasing germ cells' numbers between 14.5 dpc and birth. From birth onwards, a sharp decline of germ cells' population was observed in the first 3 days of postnatal life. Then, a transient increase of the LI, between 3 and 5 dpp, was noted. Afterwards, proliferation of germ cells ceased. These results indicate that, during fetal and neonatal life, two peaks of proliferative activity of germ cells are noticed. Following estimation of the LI for both PCNA and Ki-67, a prominent labeling for the first antibody was observed throughout the examined period. Ki-67 staining follows a similar pattern, showing, however, significant fluctuation in the obtained values, in comparison to PCNA. The significant differences observed don't seem to be simply a result of the different half lives of the two markers, but rather a consequence of additional underlying cellular activity associated with PCNA, such as DNA repair.

Sertoli cell proliferation in the fetal and neonatal rat testis: a continuous phenomenon?

Sertoli cell population kinetics, as evidenced by semi-quantitative immunolabeling for proliferating cell nuclear antigen (PCNA) and Ki-67, in developing Wistar rat male gonads of embryos and neonates [14.5 days post conception (dpc)-7 days post partum (dpp)], was investigated. Throughout the examined period a gradual increase of immunolabeled Sertoli cell number, associated with intense mitotic activity, was observed. PCNA labeling index of Sertoli cells increased from 66.67 (at 14.5 dpc) to 89.74 (at 18.5 dpc) and then dropped to 75.24 (at 20.5 dpc). At birth, the percentage of PCNA immunoreactive Sertoli cells reached 98.70% and remained high thereafter, attaining a peak value of 99.90% at 7 dpp. The percentage of Ki-67 immunoreactive Sertoli cells in the fetal testis increased from E14.5 (43.95%) to E20.5 (77.40%). The proliferation rate did not alter considerably in the neonatal testis until 5 dpp. At this point, a significant increase of the Ki-67 labeling index was observed and a peak value of 95.76% was reached at 7 dpp. The pattern of Sertoli cell proliferation with age and the establishment of the final Sertoli cell number in vivo established in the present study was compared to the results from earlier investigations reported in the literature and the observed fluctuation of dividing cell numbers, associated with immunolabeling results throughout the examined period, complements and extends existing data. An appraisal of the timing of Sertoli cell proliferation in other species, namely mouse and man, is presented. The current investigation may be useful in evaluating the potential influence of factors interfering with normal mitotic activity of Sertoli cells, including cell selection mechanisms, such as apoptosis, senescence, DNA repair and hormonal/paracrine growth modulation.

Two-dimensional electrophoresis and immunohistochemical study of calreticulin in colorectal adenocarcinoma and mirror biopsies.

PURPOSE: The purpose of this study was to analyse the polypeptide patterns of colorectal adenocarcinomas and mirror biopsies and to investigate the expression of calreticulin and the relationship of this chaperon to colon cancer. MATERIALS AND METHODS: The investigation was carried out on 21 adenocarcinomas and 21 mirror biopsies using high-resolution two-dimensional (2D) electrophoresis and immunohistochemical PAP method. RESULTS: 2D electrophoresis revealed several polypeptide patterns that were shown to be upregulated in colorectal adenocarcinomas compared to their mirror biopsies. One polypeptide spot being upregulated in colorectal adenocarcinoma, turned out to be calreticulin. The overexpression of calreticulin was confirmed by further examination in immunohistochemical level. CONCLUSION: Calreticulin was found overexpressed in colon cancer tissues as compared to the corresponding mirror biopsy tissues. The overexpression was particularly intense to high-malignancy tissues and particularly in the poorly differentiated regions of the tissue. Calreticulin showed a direct relationship to the disease stage, a fact strongly indicating that the functional role of calreticulin is directly associated with tumor growth and metastasis.

Early impact of a fat-enriched diet on behavioral responses of male and female rats.

Prolonged high-fat diets have been shown to affect an organism's stress responsiveness at the neuroendocrine level. In the present study, the authors used a 7-day protocol of fat administration in adult rats of both sexes to investigate the early behavioral impact of a moderately fat (20%) diet, often used by Western societies, on rats' reaction to acute stress and novelty. Their results show that this diet can reduce the rats' active behavioral responses to subsequent stressors and influence their corticosterone secretion. Fat-fed male rats adopted a less active behavior to cope with forced swimming stress, whereas their exploratory behavior in the open field environment was rather increased compared with chow-fed males. Fat-fed female rats exhibited a less active behavioral response to both stress paradigms compared with their chow-fed counterparts. Fat diet abolished facilitation in corticosterone secretion following a subsequent stressor in both sexes. However, only in males did fat diet exaggerate corticosterone response to novelty, irrespective of the previous stress history of the rat. These data indicate that a short-term metabolic stress can modify the rats' stress coping strategy in interaction with the gender.

Effect of different ventilatory strategies on local and systemic cytokine production in intact swine lungs in vivo.

The purpose of the study was to investigate the effect of different ventilatory strategies on local and systemic cytokine production in swine with intact lungs in vivo after 4 h of mechanical ventilation. Twenty-five swine were anesthetized and then randomized into five groups (n = 5): (1) low tidal volume zero PEEP (LVZP); (2) medium tidal volume zero PEEP (MVZP); (3) high tidal volume zero PEEP (HVZP); (4) low tidal volume PEEP (LVP); (4) high tidal volume PEEP (HVP). Respiratory rate was adjusted to maintain normocapnia and fraction of inspired oxygen (FiO2) was 1.0. TNF-alpha and IL-10 were measured in BALF and serum at baseline, 2 h, and 4 h of MV. One animal in LVZP (2 h) and two in HVP (3 h) group died before the end of the experiment. TNF-alpha level in BALF was significantly higher in LVZP and LVP at 4 h compared to baseline and the other groups. IL-10 level in BALF was significantly higher in LVP at 4h compared to baseline and the other groups. There was a statistically significant increase in serum TNF-alpha levels at 4 h in LVP group compared to baseline and the other groups at 4 h. There was statistically significant increase in serum IL-10 levels in HVZP and LVP groups at 2 and 4 h which was significantly higher compared to the other groups at 4 h. Our results show that a) low volume MV may induce local and systemic pro- and anti-inflammatory cytokine increase b) in the presence of pro-inflammatory cytokine response there is also an anti-inflammatory response in the same compartment (lungs, circulation). c) There maybe loss of alveolar-to-systemic cytokine compartmentalization.

Deregulated expression of c-mos in non-small cell lung carcinomas: relationship with p53 status, genomic instability, and tumor kinetics.

Little is known about the status of the mitogen-activating protein kinase pathways in lung cancer. One of the key molecules taking part in these pathways is the product of the c-mos proto-oncogene, which plays an important role in oocyte maturation. In vitro investigations in somatic cells have shown that c-mos expression has opposing effects on the cell cycle, which suggests that this proto-oncogene may represent an important determinant of aberrant cell function (genomic instability and altered kinetics). A recent study suggests that these effects may be p53 dependent. In view of the apparent link between c-mos and p53, we investigated in a series of 56 non-small cell lung carcinomas: a) the status of c-mos; b) its relationship to genomic instability (aneuploidy) and two kinetic parameters of the tumors, proliferation and apoptotic indexes (AI); and c) its association with p53 alterations and their concomitant relationship with the above parameters. We found c-mos overexpression in 27% of the tumors. Expression was higher in stages II/III (34%) than in stage I (17%; P = 0.018). Complete concordance was observed between c-mos overexpression and elevated c-mos mRNA levels. Because c-mos gene amplification was not detected, its deregulated expression may be attributable to increased transcription. Of the c-mos positive [c-mos(P)] cases, 77% were associated with aneuploidy. Sequencing showed two silent mutations and one missense (R-->L) at codon 22, located in a region critical for c-mos stability. In contrast to the findings of some in vitro studies, c-mos(P) tumors had a lower mean AI score than the c-mos negative [c-mos(N)] tumors had, implying that induction of apoptosis may have been defective. Indeed, 86% of the tumors overexpressing c-mos showed p53 alterations. The carcinomas with concomitant alterations of c-mos and p53 [c-mos(P)/p53 positive] had significantly lower AI values (P < 0.001) and were more frequently associated with aneuploidy (P = 0.015) than the c-mos(N)/p53 negative tumors but not the c-mos(N)/p53 positive tumors, which suggests that p53 status is the main determinant of ploidy status and apoptosis in our series. This finding also strengthens the concept that wild-type p53 plays a "safeguard" role in preventing oncogene-mediated activation.

Hairy cell leukemia: bone marrow changes following splenectomy and alpha-interferon therapy.

Thirty hairy cell leukemia patients were evaluated repeatedly for their bone marrow (BM) histology. At the time of diagnosis, 18 (60%) had diffuse, 9 (30%) had interstitial, and 2 (10%) had a mixed (diffuse and interstitial) pattern of BM disease. The follow-up BM specimens were obtained at intervals of 3-24 months, and the follow-up observation period was 12-94 months. In patients who were nontreated or only splenectomized, no significant changes were observed except of a persistent megaloblastoid picture of the red cell series and an increase of BM fibrosis. In the alpha-interferon treated patients a complete disappearance of hairy cells was observed in one and a dramatic reduction in five. The hairy cell index was reduced from a mean of 0.8 before to 0.1 after alpha-interferon therapy; most patients displayed megaloblastoid erythropoiesis. In the complete responder features of myelodysplasia were present.

B-chronic lymphocytic leukemia, small lymphocytic lymphoma, and lymphoplasmacytic lymphoma, including Waldenström's macroglobulinemia: a clinical, morphologic, and biologic spectrum of similar disorders.

Among small lymphocyte cell disorders, B-chronic lymphocytic leukemia (B-CLL), small lymphocytic lymphoma (SLL), and lymphoplasmacytic lymphoma/Waldenström's macroglobulinemia (LPL/MW) are included. B-CLL patients always have blood and bone marrow (BM) involvement by a CD5+ B lymphocyte. They frequently present with lymphadenopathy and/or hepatosplenomegaly, although in a considerable number of patients, no abnormal physical findings are found. They are prone to develop hypogammaglobulinemia, autoimmune hemolysis, or autoimmune thrombocytopenia. The typical immunophenotype of the malignant cell is CD5+, surface immunoglobulin (slg)+ (weak), CD23+, CD79b-, and FMC7-. Trisomy 12 and 13q deletions are frequent chromosomal abnormalities. The bcl-2 protein is usually overexpressed. SLL patients present with lymphadenopathy, usually generalized. Lymphocytosis is by definition absent and BM involvement, usually nodular, is found in 25% to 50% of patients. The lymph node lymphocytes are CD5+ and have a similar immunophenotype with CLL, but frequently express the LFA-1 adhesion molecule. Patients are at low risk to develop hypogammaglobulinemia, autoimmune hemolysis, or autoimmune thrombocytopenia. LPL/MW patients may present either with an accidental discovery of IgM gammopathy, symptoms related to paraproteinemia, or lymphadenopathy and/or splenomegaly. The BM is frequently involved and a leukemic picture may be found. A monoclonal gammopathy of IgM class is by definition present in MW and is frequently accompanied by hypogammaglobulinemia. Immunophenotypic studies usually reveal a CD5-, slg+ (moderate), cytoplasmic immunoglobulin (clg)+, FMC7+, and CD38+ cell. A significant proportion of cases carry the translocation t(9;14)(p13;q32) involving the PAX-5 gene. All of these disorders may potentially undergo transformation to large-cell lymphoma or Richter's syndrome. Prognostic factors have been extensively studied in B-CLL, but more studies are needed for SLL and LPL/MW. These entities should be differentiated from other B-chronic small lymphocyte cell disorders, particularly when the latter are leukemic.

Gender-dependent alterations in corticosteroid receptor status and spatial performance following 21 days of restraint stress.

The effects of 21-day exposure to restraint stress on hippocampal corticosteroid receptors and on spatial performance of male and female rats were evaluated. Stressed male animals exhibited a decrease in glucocorticoid receptor immunoreactivity in the CA1 area and the dentate gyrus. At the same time, stressed males tested on Morris water maze showed delayed learning and worse memory scores, compared with the control males. By contrast, stressed females exhibited an increase in glucocorticoid receptor immunoreactivity in CA1, similar learning ability and improved memory scores, compared with control females. In addition, stressed females showed a significant increase in mineralocorticoid receptor immunoreactivity in the CA3 area compared with controls. These data show that 21 days of restraint stress affect hippocampal corticosteroid receptors and spatial performance in a gender-specific manner. The observed changes in corticosteroid receptor levels following stress, may be causatively linked to the stress-induced alterations on spatial learning and memory.

A comparative assessment of proliferating cell nuclear antigen, c-myc p62, and nucleolar organizer region staining in non-Hodgkin's lymphomas: a histochemical and immunohistochemical study of 200 cases.

Proliferating cell nuclear antigen (PCNA) and c-myc p62 oncoprotein are two nuclear proteins expressed in proliferating and transformed cells. They can be recognized immunohistochemically in paraffin sections by the monoclonal antibodies PC-10 and c-myc 1-9E10, respectively. On the other hand, nucleolar organizer regions (NORs) are loops of DNA that carry the r-RNA genes and can be visualized in paraffin sections as black dots (AgNORs) using a silver impregnation method. It has been suggested that the mean number of AgNORs may reflect the cellular kinetics of a tumor. We independently examined 200 cases of non-Hodgkin's lymphomas using the monoclonal antibodies PC-10 and c-myc 1-9E10, as well as the AgNOR method. Our study shows a very significant correlation between PCNA, c-myc expression, and AgNOR count on the one hand and histologic grade on the other (P < .001), although a significant overlap among the three grades exists. PC-10, c-myc 1-9E10, and AgNOR scores are all shown to be linearly related, even though significant discrepancies were observed, and the correlation is stronger between PCNA and AgNORs (PCNA v c-myc p62, r = .551; PCNA v AgNORs, r = .746; c-myc p62 v AgNORs, r = .529; P < .001). A remarkable finding is that the intermediate group of lymphomas is heterogeneous as far as the proliferative rate is concerned: diffuse large cell cleaved/non-cleaved lymphomas (category G of the Working Formulation) are characterized by a significantly higher proliferative index, as evidenced by the elevated PCNA, c-myc p62, and AgNOR scores, in comparison with the other types of intermediate-grade lymphomas (P < .001). However, the proliferative rate is lower than that of the high-grade lymphomas (PCNA, P < .05; c-myc p62, P < .001; AgNORs, P < .005). No significant difference exists between B-cell and T-cell lymphomas except for the higher expression of c-myc p62 in intermediate-grade B-cell lymphomas, obviously due to the higher proliferative rate of diffuse large cell lymphomas. Based on our findings, it appears that the combination of PCNA, c-myc p62, and AgNORs provides an accurate estimate of the proliferative rate of non-Hodgkin's lymphomas in paraffin sections. Clinical studies may show whether this information has prognostic value independent of histologic classification. In addition, our results suggest that category G (diffuse large cell) lymphomas may belong to a malignancy grade higher than the intermediate grade, a suggestion consistent with their more aggressive biologic behavior.

Human papilloma virus (HPV) is possibly involved in laryngeal but not in lung carcinogenesis.

Data on human papilloma virus (HPV) involvement in preneoplastic and neoplastic lesions of the larynx and lung are limited and conflicting. The presence of HPV was investigated in a series of laryngeal specimens and non-small cell lung carcinomas (NSCLCs). The laryngeal samples (154) comprised 14 cases with hyperplasia without dysplasia, 49 with dysplasia, and 91 squamous cell carcinomas (SqCCs). The NSCLCs included 31 SqCCs, 32 adenocarcinomas, and 5 undifferentiated large cell carcinomas. Furthermore, we examined, for HPV DNA sequences, 14 bronchial metaplastic squamous lesions located next to cancerous areas. We used a sensitive nested polymerase chain reaction assay (NPCR), dot blotting, and in situ hybridization. The findings were correlated with clinicopathologic features of the patients. In the laryngeal specimens, NPCR analysis showed HPV DNA in 20 (13%) of the 154 specimens. Notably, 19 of 20 HPV-positive cases were carcinomas and only one was a mild dysplastic lesion. Typing of the carcinomas showed single HPV 6, 16, 18, and 33 infection in 1 (1.1%), 12 (13.2%), 2 (2.2%), and 1 (1.1%) samples, respectively, and HPV 6/33, 16/33, and 6/18 coinfection in three carcinomas. In situ hybridization findings were in agreement with PCR results, with the exception of two cases in which HPV 18 DNA was detected only by PCR. HPV was more frequently observed in heavy smokers than in patients with low daily cigarette consumption and nonsmokers (P = .03). There was no correlation between virus infection and gender, grade, and lymph node status of the carcinomas. None of the NSCLCs or adjacent metaplastic squamous epithelium contained HPV DNA sequences. The presented data suggest a contributory role of HPV in late stages of laryngeal carcinogenesis, because all premalignant lesions were negative but one. This study does not support a potential role of HPV in the development of NSCLCs.

Intraepithelial lumina in urothelial bladder neoplasms. A histochemical, immunohistochemical and electron microscopy study.

Intraepithelial lumina observed in 12 urothelial bladder neoplasms were studied histochemically, immunohistochemically and ultrastructurally. Both intercellular and intracytoplasmic lumina could be demonstrated showing an alcianophilic margin and containing non-sulphated acid mucins. The presence of secretory component (SC) was identified in neoplastic urothelial cells around or adjacent to intercellular lumina as well as in cells with intracytoplasmic lumina. The cells surrounding intercellular lumina revealed ultrastructurally tight junctions, microvilli and a prominent glycocalyx while cellular remnants were found quite often within the lumen. As similar histochemical, immunohistochemical and ultrastructural characteristics are also expressed in surface umbrella cells of normal urothelium it is suggested that a focal differentiation of neoplastic urothelial cells towards surface umbrella-like cells takes place and that this process is intimately related to the formation of lumina.