Pair Correlation Function of a 2D Molecular Gas Directly Visualized by Scanning Tunneling Microscopy.

The state of matter in fluid phases, determined by the interactions between particles, can be characterized by a pair correlation function (PCF). At the nanoscale, the PCF has been so far obtained experimentally only by means of reciprocal-space techniques. We use scanning tunneling microscopy (STM) at room temperature in combination with lattice-gas kinetic Monte Carlo (KMC) simulations to study a two-dimensional gas of highly mobile molecules of fluorinated copper phthalocyanine on a Si(111)/Tl-(1×1) surface. A relatively slow mechanism of STM image acquisition results in time-averaging of molecular occurrence under the STM tip. We prove by the KMC simulations that in the proximity of fixed molecules STM images represent the PCF. We demonstrate that STM is capable of visualizing directly the pair correlation function in real space.

[Caspase 1, superoxide dismutase (D-mutase) and calretinin expression in the placenta and in the basal decidua in preeclampsia]. / Expresie a lokalizácie kaspázy 1, superoxiddismutázy (D-Muyázy) a kalretinínu V placente a bazálnej decidue PRI preeklampsii.

OBJECTIVE: To determine new data related to the expression of caspase 1, superoxiddismutase and calretinin in the placenta and basal decidua in preeclampsia. MATERIAL AND METHODS: Placental and basal decidua samples from 9 preeclamptic and 9 normotensive controls were analyzed using expressions of caspase 1, superoxiddismutase and calretinin assessed by immunohistochemistry. RESULTS: Caspase 1 was expressed in placental syncythium in preeclampsia constantly, while in the control group the expression was weak or absent. In Langhans cells, in fetal sinusoidal capillary endothelia and in Hofbauer cells the expression was equal in both groups. Stronger expression was observed in stromal myofibroblasts in preeclampsia. In preeclampsia, expression of superoxiddismutase in syncythium, in Langhans cells and in decidual cells was weaker. Calretinin was not found in any placental structure. Sporadically, calretinin was expressed in the interstitial extravillous trophoblast cells, in decidual cells and in spiral arterioles in preeclampsia. CONCLUSION: The obtained morphological data correlating with some clinical and biochemical features contribute to understanding of the molecular background of preeclampsia etiopathogenesis.

Prolonged treatment of chronic renal insufficiency, acquired cystic kidney disease, simultaneous precancerous lesions and multiple tumors of left kidney.

PURPOSE OF THE INVESTIGATION: Description of precancerous lesions and kidney tumors developing in a patient with chronic uremia treated by long-term hemodialysis. MOST IMPORTANT METHODS: Light microscopy, polarization and immunohistochemistry with CK1/CK3, CK5/6, CK7, CK8, CK20, EMA, Renal cell, CD10, Ki-67, PCNA, p53 and E-cadherin antibodies were used. MAIN FINDINGS: After 11 years of hemodialysis treatment of end-stage diabetic nephropathy and chronic tubulointerstitial nephritis an urgent left-sided nephrectomy was performed because of pain and massive intrarenal bleeding. Biopsy revealed acquired cystic kidney disease associated with multiple precancerous lesions, several small papillary adenomas and a multifocal renal cell carcinoma with conventional and papillary structures with admixture of small foci of highly cellular sarcomatoid features. Severe vascular nephrosclerosis and uremic oxalosis were additional findings. The upper pole of the kidney was massively hemorrhagic. PRINCIPAL CONCLUSIONS: This case illustrates the association of chronic renal insufficiency, uremic oxalosis, long-term hemodialysis, acquired cystic kidney disease and development of variable precursor intratubular and intracystic lesions progressing to several papillary adenomas and multifocal renal cell carcinomas with variegated microscopic structures in one kidney.

Immunohistochemical markers of proliferation and vascularisation in preneoplastic bronchial lesions and invasive non-small cell lung cancer.

Autofluorescence bronchoscopy (AFB) has been shown to be sensitive to detect preneoplastic lesions in central lung airways system. In early stages of carcinogenesis, up-regulation of cyclooxygenase (COX)-2, Ki67 and/or increased angiogenesis may play a role by promoting the proliferation of tumoral cells and their resistance to apoptosis, as well as angiogenesis, tumor cell invasion and setting up of the metastatic process. The present study compared the expression of proliferative (COX-2, Ki67 and PCNA) and angiogenic markers (CD34 and NG2) between preneoplastic bronchial squamous dysplasia lesions and invasive squamous cell carcinoma. Biopsies obtained during AFB [preneoplastic lesions: low-grade (lesions up to moderate dysplasia), n=13; high-grade lesions (severe dysplasia), n=12] and surgical specimens (resections of bronchogenic carcinoma, n=11) were stained with COX-2, Ki67, PCNA, CD34 and NG2 monoclonal antibodies. Microvessel density (MVD) was analysed based on anti-CD34 immunostaining. Lesions were positive for COX-2 in 12 out of 25 preneoplastic lesions, and in 10 out of 11 invasive carcinomas (p=0.025). In preneoplastic lesions, the mean percentage of Ki67 positive cells was lower compared to invasive carcinomas (37.4+/-5.8 versus 58.6+/-8.4%, p=0.043). In addition, significant differences in MVD were observed between preneoplastic and NSCLC specimen [35.3 (25.9, 61.9) versus 22.1 (20.1, 32.6), p=0.016]. No differences were observed in the mean percentage of PCNA or NG2 positive cells between preneoplastic lesions and invasive carcinomas. Findings of the present study indicate that increases in COX-2 and Ki67 expression may be associated with the development of bronchogenic carcinomas and possibly with acquisition of an invasive phenotype. In contrast, increased CD34 expression in preneoplastic lesions suggests that increased MVD may represent an early marker of lung carcinogenesis.

Immunohistochemical study of melanocytic differentiation antigens in cutaneous malignant melanoma. A comparison of six commercial antibodies and one non-commercial antibody in nodular melanoma, superficially spreading melanoma and lentigo maligna melanoma.

In certain primary and metastatic malignant melanomas diagnostic problems may arise due to their cytologic features and/or absence of synthesis of melanin. As the "classic" combination of S-100 protein and HMB-45 may occasionally fail to stain cells of malignant melanoma, we have tested a series of commercially accessible antibodies which were so far not compared by other authors in the three most frequent subtypes of this tumor. In surgical specimens from 104 cutaneous malignant melanomas (40 nodular melanomas, 46 superficially spreading malignant melanomas and 18 lentigo maligna melanomas) the staining intensity and the proportion of neoplastic cells stained with antibodies to S-100 protein, HMB-45, NKI/C3, NKI/beteb, MART 1 (Melan A), KBA 62 and Mitf was semiquantitatively analysed. The use of this group of antibodies against melanoma-associated antigens revealed it to be a favourable supplement for the bioptical or cytological diagnosis of malignant melanoma in case the traditional/conventional combination of S-100 protein and HMB-45 antibody fails. According to the authors' experience the antibody against KBA 62 has shown to be the most effective antibody followed by the antibodies against MART-1 (Melan A) and NKI/C3.

Expression of LRP--lung resistance-related protein in the normal colorectal mucosa and in colorectal carcinoma.

Expression of LRP--lung resistance-related protein was analyzed by immunohistochemical staining with monoclonal antibody LRP-56 in 30 specimens (10 from normal colorectal tissue and 20 from colorectal carcinoma). All normal tissue samples were LRP positive. Strong LRP staining was seen in the surface epithelium and upper parts of the crypts. Similarly, colorectal carcinomas demonstrated strong staining for LRP/MVP. Staining pattern of cytoplasm of carcinoma cells was the same as in the normal mucosa. The overexpression of LRP in the colorectal carcinoma may play a role in the process of carcinogenesis or be a marker of an aggressive phenotype. It seems, the high value of LRP is a predictor of response to chemotherapy and prognoses in various tumor types. (Fig. 7, Ref: 18.).

Collagenous spherulosis in epithelial-myoepithelial carcinoma of the parotid gland. Histological and immunohistological study of a case.

Previously unreported histological and immunohistochemical features of collagenous spherulosis in an epithelial-myoepithelial carcinoma found in an 80-year-old woman are described. The multinodular tumor located in the right parotid gland was completely removed surgically. No local recurrence of the tumor appeared during the 22-month period of periodic checkups. This is believed to be the first report on collagenous spherulosis in an epithelial-myoepithelial carcinoma of the salivary gland. Different immunohistochemical characteristics of epithelial and myoepithelial neoplastic cells were found very useful for their analysis namely in parts of the tumor where one cell type greatly predominated (e.g. clear cell-type predominance). The double staining of histological sections can in this sense be recommended for the differentiation from other clear cell tumors of salivary glands allowing the correct categorization of the neoplasm.

[Pulmonary thromboembolism over a 25-year period in data from the Institute of Pathology of the P.J. Safarik Medical School in Kosice]. / Výskyt plúcnej trombembólie v materiáloch Ustavu patológie Lekárskej fakulty Univerzity P. J. Safárika v Kosiciach v odstupe stvrt'storocí.

Based on a review of archival autopsy protocols an analysis of the frequency of pulmonary thrombembolism in consecutive autopsy material is presented. The study interval for the analysis was oriented to the period between the years 1949-2000. Our analysis has shown a gradual progression of incidence of pulmonary thrombembolism, as demonstrated in relative figures. The applied preventive measures against the development of thrombosis during hospitalization have not substantially contributed to decreasing its frequency, what is not in accord with some recent observations from other countries.

Calcium oxalate granuloma of the nose of a chronically dialysed nephritic patient.

The patient was a 54-year-old woman who had been suffering from chronic tubulo-interstitial nephritis for about seven years, requiring haemodialysis. More recently, she developed a polypoid mass in the left nasal cavity causing discomfort on breathing and slight epistaxis. The tumour was of gritty consistency and measured 28 x 8 x 5 mm. Microscopy showed a lobulated almost cystic structure composed of granulation tissue with comparatively few plasma cells and many multinucleated giant cells lining the spaces filled with crystalline deposits of calcium oxalate.

Extraskeletal Ewing's sarcoma of the nose.

A 20-year-old woman presented with nasal obstruction and slight epistaxis. The obstructing lesion was excised and microscopy showed a neoplasm composed of comparatively uniform undifferentiated cells forming solid nests. The cytoplasm of the cells was clear but poorly demarcated, partly vacuolated and contained much glycogen. Although widespread in the nasal mucosa, the cells did not penetrate into the underlying bone. The cells expressed the MIC2 gene (using the CD99 marker). Electron microscopy showed simple cells with a small number of mitochondria, many glycogen particles; there were no neurosecretory granules present. Early surgical treatment followed by chemo- and radiotherapy have greatly improved the prognosis of EWS: extraskeletal Ewing's sarcoma (EWS/PNET).

[Multiple intracranial and intraspinal meningiomas in the neurocristopathy (phacomatosis) type of neurofibromatosis]. / Mnohopocetné intrakraniálne a intraspinálne meningiómy v rámci neurokristopatie (fakomatózy) typu neurofibromatózy.

Presentation of a case of a "central type" neurofibromatosis in a 56-year old woman, clinically diagnosed erroneously as multiple sclerosis with a 20 years long course. Disturbances of hearing, walking, sight, sensitivity, incontinentia, intracranial hypertension and headache represented the main symptoms. More than 120 intracranial and tens of intraspinal meningiomas represented the leading postmortem finding. In a lesser frequency spinal plexiform neurofibromas and schwannomas were also found. The death was attributed to aspiration purulent bronchopneumonia. Various types of meningioma were seen microscopically, including secretory type and a type with amyloid. Immunostaining was positive with S-100 protein and EMA. Negative expression was found with vimentin, CEA, smooth muscle actin, estrogen and progesterone receptors, amyloid A and cytokeratins. With regard to the presence or absence of key morphological features the presented case was placed according to Sobol et al. (29) into the seventh category of neurofibromatosis (NF7).

Benign glomus tumor of the superior posterior mediastinum.

An unusual location of a benign glomus tumour, outside of the constantly located regions, e.g. in the subungual location or deeply sited in extremities, was diagnosed in a 56-year-old white female in her posterior upper mediastinum. The single similar case report was published before the era of electron microscopy and immunohistochemistry and single cases of atypical and malignant forms in this unusual location were published only recently. The tumour measuring 5 x 4 x 2 centimeters has caused cough and was associated with occasional righ-sided chest pain. Its rich vascular supply has caused intensive intraoperative bleeding. The postoperative course was uneventful and the patient is free of neoplastic disease or symptoms six years after surgery. Numerous mast cells present within the tumour's interstices must be considered in relation to the possible pathogenesis of the up to now unexplained pain in glomus tumours.

[Immunohistochemical analysis of renal angiomyolipoma]. / Imunohistochemická analýza angiomyolipómu oblicky.

Immunohistochemical analysis of 6 cases of renal angiomyolipoma not related to tuberous sclerosis proved the same rate of expression of HMB 45 and NKI/C3 as well in epithelioid smooth muscle cells of the tumours. Beyond this, an unspecific expression of alpha 1-antitrypsin and alpha 1-antichymotrypsin was found which has not been mentioned in the literature up to now.