Prospective Histological Study Research Articles

ETS-Related Gene Expression in Healthy Femoral Arteries With Focal Calcifications.

Bone development-related genes are enriched in healthy femoral arteries, which are more prone to calcification, as documented by the predominance of fibrocalcific plaques at the femoral location. We undertook a prospective histological study on the presence of calcifications in normal femoral arteries collected from donors. Since endothelial-to-mesenchymal transition (EndMT) participates in vascular remodeling, immunohistochemical (IHC) and molecular markers of EndMT and chondro-osteogenic differentiation were assessed. Transmission electron microscopy (TEM) was used to describe calcification at its inception. Two hundred and fourteen femoral arteries were enrolled. The mean age of the donors was 39.9 ± 12.9 years; male gender prevailed (M: 128). Histology showed a normal architecture; calcifications were found in 52 (24.3%) cases, without correlations with cardiovascular risk factors. Calcifications were seen on or just beneath the inner elastic lamina (IEL). At IHC, SLUG was increasingly expressed in the wall of focally calcified femoral arteries (FCFA). ETS-related gene (ERG), SLUG, CD44, and SOX-9 were positive in calcifications. RT-PCR showed increased levels of BPM-2, RUNX-2, alkaline phosphatase, and osteocalcin osteogenic transcripts and increased expression of the chondrogenic marker, SOX-9, in FCFA. TEM documented osteoblast-like cells adjacent to the IEL, releasing calcifying vesicles from the cell membrane. The vesicles were embedded in a proteoglycan-rich matrix and were entrapped in IEL fenestrations. In this study, ERG- and CD44-positive cell populations were found in the context of increased SLUG expression, thus supporting the participation of EndMT in FCFA; the increased transcript expression of osteochondrogenic markers, particularly SOX-9, reinforced the view that EndMT, osteochondrogenesis, and neoangiogenesis interact in the process of arterial calcification. Given its role as a transcription factor in the regulation of endothelial homeostasis, arterial ERG expression can be a clue of endothelial dysregulation and changes in IEL organization which can ultimately hinder calcifying vesicle diffusion through the IEL fenestrae. These results may have a broader implication for understanding arterial calcification within a disease context.

Морфологическая характеристика диспластических процессов в слизистой оболочке, прилежащей к опухоли, при раке желудка кишечного типа

Introduction. Despite a significant number of publications and a concept known as Correa’s cascade, dysplas-tic processes and the mechanisms of gastric carcinogenesis, are still far from being completely understood. Dysplasia and the processes in the mucous membrane adjacent to the tumor node, their significance, and their role in the field cancerization have also been studied insufficiently. The aim of this work was to analyze the frequency of occurrence and some characteristics of high- and low-grade dysplasia in the gastric mucosa at variable distances from the tumor node. Materials and methods. We carried out a prospective histological study of surgical specimens from 49 patients with intestinal type gastric adenocarcinoma. We studied tissues from the tumor node and adjacent gastric mucosa at various distances from the tumor and assessed the frequency of occurrence and some characteristics of low- and high-grade dysplasia. Results. In the mucous membrane adjacent to the intestinal type adenocarcinoma, 73.5% of cases demon-strated low- and high-grade dysplasia. In all cases, background and precancerous processes were found in areas adjacent to the tumor node with low- and high-grade dysplasia. Conclusion. The incidence of low- and high-grade dysplasia detected in the mucous membrane adjacent to intestinal type gastric adenocarcinoma significantly decreases as the distance from the tumor node in-creases. Dysplastic changes are associated with epithelial hyperplasia, intestinal metaplasia, and inflamma-tory and atrophic changes. The results obtained support field cancerization and highlight the need to study morphological, molecular, and genetic alterations in the gastric mucosa adjacent to the tumor more deeply. The dysplastic changes present at the resection line area indicate that this fact must be considered when determining the resection line. Keywords: gastric cancer, low-grade dysplasia, high-grade dysplasia, epithelial dysplasia, intestinal meta-plasia, inflammatory infiltration, atrophy

Prevalence and clinicopathological characteristics of lipomatous neurofibromas in neurofibromatosis 1: An investigation of 229 cutaneous neurofibromas and a systematic review of the literature.

Lipomatous neurofibroma (Lnf) is a histopathological variant with adipocytes noted among cells of cutaneous neurofibromas. We aimed to investigate the prevalence and clinicopathological features of Lnfs of neurofibromatosis 1 (NF1)-associated cutaneous neurofibromas and to review the literature systematically. We also evaluated the expression of leptin (a hormone involved in lipid metabolism) in neurofibromas to better understand the pathogenesis of Lnfs. A prospective histologic study was conducted on 229 cutaneous neurofibromas from 85 NF1 individuals. Leptin expression was immunohistochemically evaluated in 111 cutaneous neurofibromas. To systematically review the literature, two authors independently performed literature searches without year restriction. Forty (17.5%) neurofibromas were lipomatous. Lnfs were significantly larger lesions and associated with females. Eighteen (7.9%) of all neurofibromas had multinucleated floret-like giant cells, and these were associated with Lnfs. All neurofibromas expressed leptin. We systematically reviewed 13 articles. Three large studies investigated Lnfs mainly in sporadic neurofibromas and suggested that 0.3% to 8.0% of tumors (NF1 and sporadic) are Lnfs. In NF1, Lnfs are common, mainly in larger tumors and women. All cutaneous NF1-neurofibromas express leptin. It is unknown if the expression of leptin accounts for the lipomatous variant, but it may have a role in the pathogenesis of cutaneous neurofibroma.

A Histological Comparison of Two Human Acellular Dermal Matrix Products in Prosthetic-Based Breast Reconstruction.

Background:Acellular dermal matrices (ADMs) are an integral component of breast reconstruction. The ideal matrix would be relatively immuno-inert, allow rapid vascularization, and be affordable. The purpose of this study was to histologically compare 2 commonly used ADM products.Methods:This is a prospective histological study of 17 patients (20 breasts) following prosthetic-based breast reconstruction with ADM: Alloderm (LifeCell Corp, Branchburg, N.J.) or Cortiva (RTI Surgical, Alachua Fla.). Biopsies were taken from the dermal matrix and natural capsules surrounding the expander/implant during secondary surgery [Range, 72—694 days (mean, 217 days)]. Biopsy specimens were prepared via hematoxylin and eosin, Masson's trichrome, elastin, and transforming growth factor (TGF)-1 stains. Quantitative analysis of staining was performed with ImageJ software. The clinical outcome of each patient is analyzed in relation to capsule architecture and ADM performance.Results:There were 7 breasts in the Alloderm group and 13 in the Cortiva group. Both groups had similar demographic, aesthetic results, and complication profiles. The TGF-1 staining demonstrated significantly lower levels in the Cortiva capsules (P = 0.0139). The percentage of elastin and collagen are similar in the Cortiva, Alloderm, and natural peri-implant capsules. The native capsules show a significantly greater number of blood vessels when compared with Cortiva and Alloderm (P = 0.0371 and P = 0.0347, respectively); however, there is no difference in vascular pattern between the 2 dermal matrices.Discussion:Postoperatively, Cortiva demonstrates equal vascularity with less TGF-1 activation compared with Alloderm. The clinical success and complication profile were similar between the Alloderm and Cortiva patients.

Histopathological and Radiographic Analysis of Dental Follicle of Impacted Teeth Using Modified Gallego's Stain.

In the WHO classification of odontogenic tumours, hard tissue formation has been considered as a sub-classification however, this parameter has not been much explored in dental follicle in literature. Epithelial-mesenchymal interactions play an important role in odontogenesis and its associated pathologies; therefore research on dental follicle should also include mesenchymal components along with epithelial components. Additionally, special stains to identify the nature of such depositions in dental follicle have been less explored. Modified Gallego's stain is such an example which has not been tried in odontogenic lesions which makes this study unique. Aim of this study was to study histopathological variations in dental follicle, the nature of calcification and depositions using Modified Gallego's stain and to correlate histological features of dental follicle with pericoronal width radiographically. A prospective histological study of the dental follicles of 50 impacted teeth was carried out to microscopically evaluate the dental follicular tissues for pathological changes, and to correlate it with pericoronal radiolucency. Impacted teeth with pericoronal radiographic width less than 3mm were included in the study and symptomatic teeth were excluded. Further Modified Gallego stain was used to differentiate the nature of hard tissue formation in dental follicle tissues. Dental follicle histologically showed pathological changes resembling dentigerous cyst, ameloblastoma, odontogenic fibroma (Simple and WHO Type), clear cell odontogenic tumour, neurofibroma, neurilemmoma and mucoepidermoid carcinoma. The dental follicle surrounding an impacted tooth has the potential to differentiate into a wide variety of tissue types, and thus shows the potential for cyst and tumour development which was observed in this study in most of the specimens with normal follicular width radiographically.

Fetal placental inflammation is associated with poor neonatal growth of preterm infants: a case-control study

Objective: To determine whether there is an association between histological chorioamnionitis (HCA) and postnatal growth of preterm infants in the neonatal period.Method: This case–control study is part of a larger prospective histological study on placentas performed in all deliveries prior to 32 weeks of gestation. Eligible cases involved all placentas with a diagnosis of HCA. Control subjects were those without HCA, matched 1:1 with case subjects according to gestational age (±1 week). Placental inflammatory status and serial weight gain were analyzed for all infants during the first four postnatal weeks. Based on placental inflammation extension, HCA was defined as maternal HCA (MHCA) or fetal HCA (FHCA).Results: Of the 320 mother–infant pairs, 71 (22.1%) presented with HCA (27 MHCA and 44 FHCA). Decreases in weight gain at 21 and 28 days were associated with the presence of FHCA (β coefficient ± SE = −4.40 ± 2.21, p = 0.05 and −6.92 ± 2.96, p = 0.02, respectively), whereas no significant differences were found between MHCA and no-HCA groups. FHCA and MHCA were not identified as risk factors of weekly weight gain, after adjusting for possible confounders (maternal ethnicity, parity, smoking during pregnancy, infant gender, IUGR status, SGA status, antenatal steroids, total fluid intake, late-onset sepsis, BPD).Conclusions: We found an association between fetal placental inflammation and poor neonatal growth but we were not able to identify a specific week wherein weight gain could be mostly affected. Placental findings may be used to identify preterm infants at risk of postnatal growth failure.

Tonsillar Crypts and Bacterial Invasion of Tonsils: A Pilot Study

Objective: To investigate histologically if a lack of protection of the deep lymphoid tissue in tonsillar crypts by an intact epithelial covering is an aetiological factor for tonsillitis. Method: A prospective histological study of the tonsillar crypt epithelium by immunostaining for cytokeratin in 34 consecutive patients undergoing tonsillectomy either for tonsillitis or tonsillar hypertrophy without infection (17 patients in each group). Results: Discontinuity in the epithelium was found in 70.6% of the groups of patients with tonsillitis and in 35.3% of the groups of patients with tonsillar hypertrophy. This is of borderline significance. Conclusion: We found no clear correlation between tonsillitis and a defect in the tonsillar crypt epithelium. Tonsillitis might be due to immunological differences of subjects rather than a lack of integrity of the crypt epithelium. Further study with larger sample size and normal control is suggested.

Preterm premature rupture of membranes, chorioamnion inflammatory scores and neonatal respiratory outcome

To evaluate whether histological chorioamnionitis (HCA), in the setting of preterm premature rupture of membranes (PPROM), affects infant respiratory outcome. A prospective histological study on 287 consecutive placentas was performed in preterm infants (<or=32(+6) weeks gestation), categorised into four groups: according to the presence or absence of HCA, in the setting or in absence of PPROM. Neonatal intensive care unit, Department of Pediatrics, Padua University, Padua, Italy from January 2001 to December 2006. Among the 287 NICU admitted preterm infants, 68/287 (23.6%) presented with HCA, 16/68 (23.5%) with a coexisting fetal inflammatory response, and 74/287 (25.7%) with PPROM. HCA was associated with a greater frequency of vaginal delivery (P < 0.0001), lower gestational age (P < 0.0001) and lower birth weight (P < 0.01). HCA had no effect on fetal lung maturation, however, it was a significant risk factor for CLD (RR; 95% CI 2.08; 1.30-3.33). HCA and the fetal inflammatory response were also significant risk factors for PPROM (RR; 95% CI 2.07; 1.42-3.03 and 2.64; 1.71-4.09 respectively). Conversely, HCA in the setting of PPROM failed to reveal any RDS protection or subtype CLD risk. Multivariate analysis demonstrated significant independent effects of presence of maternal HCA (P = 0.04), gestational age (P < 0.0001) and interaction HCA-gestational age (P = 0.04) on CLD development, regardless of the presence of fetal HCA or fetal HCA-gestational age interaction, PPROM or PPROM-gestational age interaction. Histological chorioamnionitis is a significant PPROM and CLD risk factor, but it fails to provide any protection from RDS. HCA in the setting of PPROM also failed to reveal any RDS protection or subtype CLD risk.

Clinically unapparent melanocytic nevi on the prepuce

Melanocytic nevi from the genitalia are uncommon. Nevi on the vulva are much better described than nevi on male genitalia. To our knowledge, a systematic study of preputial melanocytic nevi has not been reported. To investigate the frequency of clinically unapparent melanocytic nevi on a series of preputial excisions. We undertook a prospective histologic study of the prepuce obtained in a series of 372 consecutive circumcisions for phimosis performed during the period between January 2000 and December 2002. Incidental preputial melanocytic nevi were detected in four (1.1%) patients. Lesions were dermal in nature, most of them showed pigment in superficial dermal nests and had pseudovascular spaces. There were no cytologic atypia, mitotic figures, architectural disorder or inflammatory infiltrate. The mean (standard deviation, SD) of the maximum diameter was 1.08 (0.85) mm (range 0.34-1.79 mm). The mean age (SD) of the patients was 41.5 (4.95) years (range 29-58). Incidental melanocytic nevi, although uncommonly, can be observed in the prepuce. They are detected in adults and may pose a diagnostic challenge when they are detected in the setting of concurrent malignant melanoma.

Tonsillar crypts and bacterial invasion of tonsils, a pilot study

Objective: To investigate histologically if a lack of protection of the deep lymphoid tissue in tonsillar crypts by an intact epithelial covering is an aetiological factor for tonsillitis. Method: A prospective histological study of the tonsillar crypt epithelium by immunostaining for cytokeratin in 34 consecutive patients undergoing tonsillectomy either for tonsillitis or tonsillar hypertrophy without infection (17 patients in each group). Results: Discontinuity in the epithelium was found in 70.6% of the groups of patients with tonsillitis and in 35.3% of the groups of patients with tonsillar hypertrophy. This is of borderline significance. Conclusion: We found no clear correlation between tonsillitis and a defect in the tonsillar crypt epithelium. Tonsillitis might be due to immunological differences of subjects rather than a lack of integrity of the crypt epithelium. Further study with larger sample size and normal control is suggested.

Prichard's structures of the fossa ovalis are age‐related phenomena composed of nonreplicating endothelial cells: the cardiac equivalent of cutaneous senile angioma

Prichard's structures or minute endocardial deformities with lacunas of capillary size lined by plump endothelial cells located in the fossa ovalis are an age-related alteration of unknown origin. In this report the histogenesis, the proliferative potential and the incidence in the aged of these structures are investigated. We have undertaken a prospective histological study of the fossa ovalis in a series of 111 consecutive hearts of patients aged >/=70 years obtained at autopsy. Included in this study was immunohistochemical staining for vimentin, CD31, CD34, thrombomodulin, c-kit (CD117), Ki67 (MIB1) and vascular endothelial growth factor receptor 2 in six cases showing these structures. Prichard's structures were observed in 50 hearts (45%), and were more frequent in males. We confirmed that these structures are age-related phenomena. Subendothelial structures were more common than intracavitary structures. Most individuals had Prichard's structures located on the right side; however, the structures were more numerous on the left side of the fossa ovalis. The immunohistochemical study revealed that Prichard's structures consisted of adult, fully differentiated, postmitotic-type endothelial cells. We suggest that Prichard's structures are formed by infolding of the endothelial lining of the endocardium of the fossa ovalis as an irritational response to altered blood flow, eddies or turbulence. A parallel can be established between Prichard's structures and senile angiomas as both structures increase with age; they are not genuine neoplasms; and they are overgrowths made up of endothelial cells with terminal differentiation. We propose that Prichard's structures are the cardiac equivalent of cutaneous senile angioma.

Renal Grafts From Elderly Donors: Histological Studies and Long-Term Results

To satisfy the increasing requests for renal grafts, elderly donors are increasingly accepted for kidney transplant at many centers. The main unresolved question is the long-term effect on graft survival of potential histological lesions due to donor age. We present a prospective histological study performed from January 1997 to December 2001 on 184 consecutively transplanted renal grafts in which the only criterion for graft acceptance was a normal value of serum creatinine upon admission to the intensive care unit independent of donor age. At the end of the study, 57 recipients (31%) of mean age 55 years (range 39 to 67 years) received a renal graft from donors aged more than 60 years (mean age 66 years; range 60 to 75 years), this cohort denoted as older donor kidney transplant group (ODKTG) and 127 recipients (69%) with a mean age of 49 years (range 21 to 63 years) received a renal graft from donors whose age was lower than 60 years (mean age 49 years; range 16 to 59 years), a cohort denoted as the younger donor kidney transplant group (YDKTG). The two groups were comparable for time of dialysis, cold ischemia time, immunosuppression therapy, grading of histological damage. At the end of the study with a mean follow-up of 5.6 years (range 3.5 to 7.5 years), primary graft nonfunction and delayed graft function were significantly more represented in the ODKTG than the YDKTG. Cumulative patient and graft survival was 84.3% and 79.4% in the ODKTG, respectively, and 93.8% and 85.9% in the YDKTG, respectively ( P = NS). Cumulative serum creatinine values were 1.98 mg/100 mL in ODKTG and 1.65 mg/100 mL in YDKTG ( P = NS). In conclusion, renal grafts from older donors presented histological damage comparable to that seen among renal grafts from younger donors.

Immunohistochemical Differentiation and Localization Analysis of Sweat Glands in the Adult Human Axilla

The classic concept of axillary glands differentiates between eccrine glands, producing abundant clear, nonodorous sweat; and apocrine glands, excreting small amounts of turbid, odorous milky sweat. A third type of sweat glands, the "apoeccrine" glands, were recently identified. To define the different types of sweat glands and their location and number, the authors carried out a prospective histologic study on adult human axillary skin, including various immunohistochemical markers. Forty-three consecutive Caucasian, subjectively normhidrotic patients, who underwent a surgical procedure in the axilla unrelated to the axillary glands, were included in the study. For verification of normhidrosis, the gravimetric test was carried out by measuring the amount of sweat secretion per minute. Then, a 1 x 1-cm measuring piece of skin and subcutaneous tissue was excised in the apex of the axilla, divided into three samples--altogether, 129 samples--and processed for histologic examination. In the dermis, the authors found only very few eccrine (average, 0.3 gland/cm in only 12 percent of all patients) and apocrine glands (average, 0.1 gland/cm in only 4.7 percent of patients), and no apoeccrine glands in any patient. In the subcutaneous tissue, the mean number of glands per centimeter squared was 10 for the eccrine glands, nine for the apocrine glands, and six for the apoeccrine glands. In the authors' Caucasian subjects, all or most of the sweat glands were found in the subcutaneous tissue near the border to the dermis and not in the dermis. For extremely hyperfunctioning sweat glands, the authors recommend less radical surgical methods, with the preservation of skin, based on the knowledge that most glands are localized in the subcutaneous tissue.

Histological chorioamnionitis and neonatal leukemoid reaction in low-birth-weight infants

We investigated whether histological chorioamnionitis (HCA) is a risk factor predisposing to leukemoid reaction (LR) and whether LR is associated with the preterm parturition syndrome and the systemic fetal inflammation response syndrome. A prospective histological study on placentas was performed in preterm infants (<or=32(+6) weeks' gestation) admitted to level III neonatal intensive care unit of Padua University from January 1998 to December 2003. Development of LR was related to evidence of HCA. Among the placentas of the 223 preterm examined infants, 61 (27%) were diagnosed with HCA. Overall incidence of LR was 5.3%. Of 61 preterm neonates with HCA, 8 (13%) developed LR; moreover, 4 (2%) of 162 preterm infants without HCA developed LR (odds ratio = 7.4). Neonates with both LR and HCA differ from neonates with LR and without HCA in occurrence of prolonged rupture of membranes (62.5% versus 0%, P < .01), mode of delivery (37.5% versus 100% cesarean delivery, P < .01), gestational age (26 +/- 1.6 versus 29.7 +/- 1.7 gestational weeks, P < .01), and bronchopulmonary dysplasia incidence (63% versus 25%, P < .01). Histological chorioamnionitis placental findings increase the risk for neonatal LR. The LR in low-birth-weight neonates with HCA is significantly associated with earlier delivery and bronchopulmonary dysplasia. Pathogenetic mechanisms of neonatal LR in low-birth-weight infants without HCA remain undefined.

395 Brain Damage of Extremely Low Birth Weight Infants with Histopathologic Chorioamnionitis

Background/aims: Neonatal cerebral white matter injury is the major precursor for neurological impairment and cerebral palsy. Chorioamnionitis has been associated with periventricular leukomalacia (PVL) in very low birth weight (VLBW) infants. We evaluated the association between occurrence and pathological severity of histological chorioamnionitis (HCA) and brain damage in VLBW infants. Methods: A prospective histological study on 287 placentas was performed in preterm infants (< 32+6 weeks gestation), consecutively admitted to III level NICU of Padua University from January 1999 to December 2004. Development of intraventricular hemorrhage (IVH) or PVL was related to the evidence of HCA and to chorioamnion inflammatory scores, according to Naeye et al. Results: Among the 287 NICU admitted preterm infants, 68 (23.6%) showed HCA, and 39/287 (13.5%) had brain damage, IVH or PVL. Brain damage was present in 15/68 (22%) of infants in the setting of HCA and in 24/219 (10.9%) of infants in the absence of HCA (p<0.05). HCA is also associated with a significantly increased frequency of PVL (5.8% vs 0.4%; p< 0.01), but failed to reveal any association with IVH (16.1% vs 10.5%; p=0.2). However, severe fetal HCA, stage II-III vs I and grade II-III vs I, were unrelated to brain damage. HCA infants were comparable to non-HCA infants in all selected demographics and clinical variables, except for increased vaginal delivery and lower gestational age (27±2.5 vs 30±2.3; p<0.05) Conclusions: HCA in preterm infants <32 weeks gestation is significantly associated with PVL occurrence, unrelated to fetal sites and severity of chorioamnion inflammation, but fails to induce any effect on IVH occurrence.

Factors which could affect the severity of post-traumatic pulmonary fat embolism--a prospective histological study

Each fracture of long or pelvic bones as well as large contusions of subcutaneous fat tissue cause releasing of fat globules that rapidly penetrate into circulation through the ruptured veins of the injured tissue, and reach the lung circulation [1,2]. During the first phase, fat emboli block the functional lung circulation by their mechanical effect in capillaries producing so called isolated post-traumatic lung fat embolism [3]. The surface layer of a fat embolus, which is practically in liquid state, behaves as a membrane of very high density, i.e., as it is under high pressure which obstruct the blood stream [4] that is finally stopped at the level of lung blood vessels with diameter of approximately 20 mu [5]. This pathophysiological mechanism produces cor pulmonale acutum, with poor pathological findings [8]. Nowadays, the post-mortem diagnosis of lung fat embolism is based on microscopical examination of tissue specimens, usually prepared with special histological staining (Sudan III) [9]. The grading of fat embolism according to Sevitt's criteria is generally accepted [10]. Taking of slices from apicoventral areas of the lungs has been recommended [11]. With longer outliving period, the total number of fat emboli in the lung circulation gradually decreases, due to their disintegration and resorption. It has been stated that fat globules completely disappear about 4-6 weeks after injury, and that they should not be searched for microscopically in this post-traumatic phase [11]. The aim of our work was to determine whether the age of injured, their gender, total severity of trauma, outliving period, and hypovolemic shock that develops after injuring, may induce development of more severe forms of post-traumatic lung fat embolism. A prospective histological study was performed on the autopsy material of the Institute of Forensic Medicine in Belgrade. The analyzed sample consisted of individuals with injuries that might be a source of fat emboli (fractures of long bones, large contusions of subcutaneous fat tissue). The lung slices were systematically taken and stained with special fat staining (Sudan III). In each particular case, the grade of lung fat embolism was counted on the basis of microscopical appearance, according to Sevitt's criteria. The total severity of trauma was estimated by calculation of the Injury Severity Score (ISS) [13, 14]. In no cases from the analyzed sample, the fat embolism was mentioned as either singular or plural cause of death. The obtained results were analyzed by means of appropriates statistical methods (ANOVA, LSD-test, chi 2 test. Man-Whitney test, Fischer's test of correct probability). The analyzed sample included 58 fatally injured individuals, 39 males and 19 females. The average age was 54.10 years (SD = 16.56), the average value of ISS was 34.69 (SD = 5.88), and the average outliving period was 3.74 days (SD = 5.88). However, all these data look differently when the analyzed sample has been stratified and analyzed according to the estimated grade of lung fat embolism. It was not showed that severity of lung fat embolism depends on sex of the injured (chi 2 = 0.842; p > 0.05). The groups with the slightest and the most severe grade of lung fat embolism are statistically significantly different in relation to age of individuals (ANOVA, p = 0.017). By means of LSD test, it has been showed that the group with the most severe grade of lung fat embolism (grade III) is statistically significantly different comparing to other two groups (with grade I and II) in relation to the age of injured (the values are p = 0.16 and p = 0.19 respectively, and the both groups are less than p = 0.05). In the group with the most severe grade of lung fat embolism, the older individuals are statistically significantly represented comparing to other two groups. The analysis of our sample showed that the most severe grade of post-traumatic lung fat embolism (microscopical grade III according to Sevitt's criteria) was determined in older individuals, more severely injured, and with shorter outliving period. The severity of fat embolism depends neither on sex of the injured, nor on development of post-traumatic hypovolemic shock. The obtained results related to the influence of hypovolemic shock on severity of fat embolism should be accepted with a caution. Namely, sometimes there is an intention to simplify a procedure of creating of autopsy conclusion about the cause of death, so that loss of blood is not mentioned at all, in spite of fact that it could have been a concurrent cause of death, while in other cases exsanguination is designated as a sole cause of death, forgetting the possibility that fat embolism could have really been the immediate cause of death.

Non-alcoholic steatohepatitis: a common cause of progressive chronic liver injury?

Aim: To investigate the natural history of patients with non-alcoholic steatohepatitis by means of a prospective histological study. Methods: One thousand five hundred and seventy one patients underwent liver biopsy...

Prichard's structures of the fossa ovalis are not histogenetically related to cardiac myxoma.

Cardiac myxomas are neoplasms of unknown histogenesis. They are thought to arise from hypothetical subendothelial vasoformative reserve cells or from primitive cells which reside in the fossa ovalis and surrounding endocardium. In 1951 Prichard described a kind of microscopic endocardial structure with a predilection for the interatrial septum, which were suggested to be related to cardiac myxomas. To confirm the existence of Prichard's structures and to clarify their role in the genesis of cardiac myxomas, we examined histologically the fossa ovalis and we performed an immunohistochemical study of the endocardial abnormalities that were found. A prospective histological study of 100 interatrial septa and an immunohistochemical study of three out of the 12 endocardial abnormalities that were detected, as well as of four conventional cardiac myxomas were accomplished. Antibodies were used to vimentin, CD31, CD34, alpha-smooth muscle actin, S100 protein, thrombomodulin, calretinin and c-kit (CD117), a tyrosine kinase growth factor receptor for stem cell factor usually expressed by embryonic/fetal endothelium. Structures similar to the ones described by Prichard were found in 12% of septa, most of them in the left side of the fossa ovalis. The hearts with these structures were from patients 10 years older than the ones without them (72 +/- 10 versus 62 +/- 16 years, P=0.006). Immunohistochemically the cells comprising Prichard's structures were positive for vimentin, CD31, CD34 and thrombomodulin, and negative for alpha-smooth muscle actin, S100 protein, calretinin and c-kit. Therefore these cells seem to be mature endothelial cells, but not primitive multipotential mesenchymal cells. Furthermore, these cells were not found in the atrial tissue from the bases of any of the conventional cardiac myxomas. Our study suggests that there is no apparent relation between Prichard's structures and cardiac myxomas, and that Prichard's minute endocardial deformities are age-related phenomena.

Histological diagnosis of cytomegalovirus hepatitis in liver allografts.

AIMS--To determine the incidence of histologically documented cytomegalovirus (CMV) hepatitis following orthotopic liver transplantation (OLT) and to assess the effectiveness of immunohistochemistry and in situ hybridisation (ISH) in detecting CMV. To describe the histological pattern most frequently associated with CMV hepatitis in order to select the biopsy group in which these modern techniques are most effective. METHODS--A prospective histological study was carried out on 853 biopsy specimens, obtained from 191 liver allografts (160 patients). Specimens were stained with haematoxylin and eosin and immunohistochemically (avidin-biotin complex) using monoclonal antibodies directed against early and late CMV antigens. A retrospective selection was made of 23 specimens with viral inclusion bodies in cytomegalic cells (group A) to characterise the most frequently associated histological pattern, and of 34 other specimens without viral inclusion bodies (group B) but with the same microscopic features as group A. Re-cuts from both specimen groups were studied using immunohistochemistry and ISH with a CMV specific complementary DNA probe. RESULTS--CMV infection was confirmed in 35 specimens (29 by immunohistochemistry, 23 by presence of inclusion bodies in haematoxylin and eosin stained sections, 16 by ISH) from 27 patients (incidence 16.9%). CMV hepatitis was diagnosed within 46 +/- 19 (range 21-114) days posttransplant. Twenty on (91.3%) of the 23 biopsy specimens with inclusion bodies (group A) displayed heterogeneous inflammatory foci disseminated throughout the hepatic lobule. Nineteen specimens (82.6%) were positive by immunohistochemistry and 14 (60.9%) by ISH. In eight (23.5%) of the 34 group B specimens CMV infection was confirmed by immunohistochemistry (n = 6) or ISH (n = 2). Another 12 (35.3%) of the group B specimens negative on staining with haematoxylin and eosin, immunohistochemistry and ISH came from allografts in which previous or subsequent biopsy specimens were CMV positive. CONCLUSIONS--Demonstration of cytomegalic inclusion bodies in haematoxylin and eosin sections is sufficient for a diagnosis of CMV hepatitis. The routine use of immunohistochemistry in all allograft biopsy specimens in more sensitive than demonstration of inclusion bodies by staining with haematoxylin and eosin but may yield false negative results because of the focal distribution of positive cells. ISH was less sensitive than staining with haematoxylin and eosin and/or immunohistochemistry. A histological picture of "disseminated focal hepatitis" without viral inclusion bodies selects a group of allograft biopsy specimens in which immunohistochemistry and/or ISH may improve detection of CMV.

A prospective study of first attacks of inflammatory bowel disease and infectious colitis. Histologic course during the 1st year after presentation.

To investigate the possibilities of differentiating between inflammatory bowel disease (IBD) and infectious colitis on histologic grounds, a prospective histologic study of 105 patients with a first attack of colitis was undertaken. Rectal biopsies were performed on four occasions during 1 year. The strongest predictor of IBD was basal plasmacytosis, followed by more than two vertical crypt branches per medium-power field, crypt distortion, villous mucosa, and mucosal atrophy. These signs were rarely found among patients with infectious colitis. Their frequency increased with the interval between initial symptoms and the first biopsy. To study the development of histologic features in the absence of treatment, the IBD patients were divided into groups depending on this interval. Focal or diffuse basal plasmacytosis increased from 38% in the group with an interval of 1-15 days to 89% in those who presented in 121-300 days, and crypt distortion from 0% to 78%, whereas absence of signs indicating IBD decreased from 62% to 11%. The presence of focal basal plasmacytosis seems to be the earliest sign of IBD. The frequency of histologic signs indicating IBD was maximal (88%) at the 1-week biopsy. After recovery, the basal plasmacytosis and villous mucosa decreased, whereas crypt distortion and mucosal atrophy remained unchanged. Early treatment did not prevent the appearance of any feature.