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Introduction. Congenital asplenia is an extremely rare condition that can be separate entity due to a specific defect of spleen development or may occur in the context of a malformation syndrome. The patients with asplenia have thrombocytosis and susceptibility to life-threatening infections. Case report. We report a 52-years-old female patient with isolated congenital asplenia with pseudothrombocytopenia and giant platelets. Estimation of platelets life with radioactive indium showed normal lenght of platelets life (9 days). Flow cytometric analysis of platelets showed normal expression of CD41 and CD42b antigens. The mean platelet diameter of asplenic patient measured on the ultrathin sections by the transmission electron microscope was significantly higher than in the healthy individuals (3.81 ± 1.16 μm vs. 2.37 ± 0.61 μm, p < 0.05). There were very few platelets of diameter more than 4 μm found in healthy individuals (around 1%) in comparison to > 40% of the patient’s platelets. The ultrastructural studies revealed normal morphology of megakaryocytes. The platelets were uniformly spheroid in shape with conspicuous pseudopodia and the centralization of granules. There were no marginal bands of microtubules inside the platelets. Conclusion. The first case of congenital asplenia with the pseudothrombocytopenia and giant platelets is presented. We discussed the pathogenesis of giant platelets and possible relation of observed ultrastructural changes of platelets with the severe three-vessel coronary artery disease in our patient.

The aim of the study was to investigate the morphology of mesothelial cells of the peritoneum of patients with terminal renal failure (TRF), taken by the biopsy immediately before the onset of peritonal dialysis (PD), and to compare it with the findings in patients with PD. The samples were prepared in the way standard for light microscopy and transmission electron microscopy. In patients with TRF intracytoplasmatic inclusions could be observed, unusual protrusions of mesothelial apical surfaces, deformation of mesothelial cells and their detachment from the basal membrane, as well as the dilatated cisternae of granulated endoplasmatic reticulum with filamentous structures in some of them. In patients on PD cytoplasmic protrusions of different shapes and contents were observed at the surface of mesothelial cells, multiplication of basal membrane, occurrence of young forms of mesothelial cells as well as the detachment of those cells from the basal lamina. [ABSTRACT FROM AUTHOR]

By application of morphological and ultrastructural methods for identification of apoptosis, we analyzed the incidence of morphologically evident apoptosis in the bone marrow of 30 patients with myelodysplastic syndrome (MDS), and in the bone marrow of 12 healthy individuals. According to FAB classification, out of 30 patients, eight (26.6%) had refractory anemia, three (10%) had refractory anemia with ringed sideroblasts, 14 (46.6%) had refractory anemia with excess of blasts and two (6.8%) had refractory anemia with excess of blasts in transformation. Three patients (10%) had chronic myelomonocytic leukemia. Cells in apoptosis were examined on semithin slides and expressed as the apoptotic index (AI) (percent counted on at least 1000 cells). An overall increase in apoptosis in patients with MDS was found (median AI in patients vs controls, 3.13% vs 1.05%, P < 0.01 by Mann-Whitney U test). Also, negative correlation between AI and white blood cell count was found (linear r= -0.53, or Spearman rank R= -0.52, both P < 0.01). In patients with evident karyotype changes AI was not higher than in patients with normal karyotype. This suggests that discrete alterations in apoptosis are present even in karyotypically 'normal' clones. Our results strongly support the hypothesis that apoptosis has a role in ineffective hematopoiesis and may be a mechanism responsible for the paradox of hypercellular bone marrow and peripheral blood pancytopenia in MDS. [ABSTRACT FROM AUTHOR]

Background/Aim. The number of patients with end-stage renal diseases treated with chronic dialysis is increasing over the last years. Long-term peritoneal dialysis is associated with progressive development of structural and functional alterations of peritoneal membrane. The aim of the study was to analyze ultrastructural alterations of mesothelial monolayer and submesothelial tissue in a modified nonuremic experimental model of peritoneal dialysis in rabbits. Methods. The study was performed on 5 healthy Chinchilla rabbits. Surgical procedures of implantation and removal of peritoneal catheter, prevention of catheter clothing, prevention of infection and dialysate instillation were performed according to previously described protocols. Peritoneal tissue samples were collected upon catheter placement and removal after a 5-week follow-up and processed for transmission electron microscopy (TEM) examination. Results. The rabbits tolerated anesthesia, surgical procedure and the applied regimen of dialysate instillations well. The animals recovered completely and no adverse effects were noted. In the animals treated with peritoneal dialysis instillations, TEM revealed alterations of the mesothelial monolayer and submesothelial tissue. The mesothelial cells in direct contact with dialysis fluid were prone to shrinking. They lost the typical cobblestone morphology and assumed a flattened shape. The mesothelial cells were often detached from the basement membrane. These cells showed euchromatic nuclei, higher number of microvilli in their apical part and very numerous vesicles. A higher quantity of collagen fibers was noticed in the peritoneal lamina propria in close relation to the basement membrane of mesothelium. The nuclei of the fibroblasts were also euchromatic. Numerous mitochondria, granules and vesicles were present in their cytoplasm. Conclusion. The used rabbit model of peritoneal dialysis is simple, practical to perform, reproducible, not expensive and not requiring advanced devices. It is suitable for obtaining peritoneal tissue samples for histological examination and can be used to analyze the effects of dialysis solutions on the rabbit peritoneal membrane. [Projekat Ministarstva nauke Republike Srbije, br. 145070]

Introduction. Incontinentia pigmenti (IP) is a rare X-linked dominant genodermatosis. Mutations of the IKBKG gene are the only known cause of IP. The presence of other than skin changes is important in the diagnosis of atypical IP cases when skin changes are discrete. Objective. The study was designed to analyze clinical manifestation, family histories and the frequency of IKBKG gene mutation in IP patients in Serbia for the first time and to compare them with other reported findings. Methods. Two Serbian unrelated families with eight female subjects were investigated. Blood samples were used for IKBKG exon 4-10 deletion testing using modified PCR protocol. For probands pathohistological and ultrastructural analyses of skin biopsies were done. Results. Positive clinical diagnosis according to IP criteria was present in seven cases. In six of them, including probands, positive molecular gene testing for IKBKG exon 4-10 deletion was present. Conclusion. This is the first report of genetically confirmed IP in two Serbian families. The IP patients presented a common IKBKG exon 4-10 deletion. The frequency and type of IKBKG mutation found in investigated IP patients in Serbia were similar to results of other studies. Various clinical features of investigated patients have allowed us to demonstrate that molecular genetic testing which specifically detects the common IKBKG mutations, the only known cause of IP, is useful in diagnosing IP especially in mild or atypical cases. The molecular genetic testing of the IKBKG mutations may be helpful for rapid confirmation of IP diagnosis, prenatal diagnosis and carrier detection.

Introduction. Incontinentia pigmenti (IP) is a rare X-linked dominant genodermatosis. Mutations of the IKBKG gene are responsible for IP. A deletion of exons 4-10 can be found in 80% of patients with IP. There are 69 different mutations of the IKBKG gene that have been reported. Case Outline. A proband, female patient from a family without previously diagnosed IP is reported. She had skin and dental changes typical of IP. The diagnosis was made according to updated IP criteria. Pathohistological and ultrastructural analysis of skin biopsy confirmed the diagnosis. However, the common deletion of exons 4-10 in the IKBKG gene could not be detected. Sequencing revealed the indel (deletion/insertion) mutation c.641_647delGCATGGAinsAT (p.Arg214HisfsX38) in exon 5 of the IKBKG gene. Because this mutation could not be detected in the unaffected mother of the proband, it seems to be a de novo mutation. Conclusion. The registered novel frameshift IKBKG mutation c.641_647delGCATGGAinsAT (p.Arg214HisfsX38) can be considered to be the cause of IP in this case. [Projekat Ministarstva nauke Republike Srbije, br. 175005]

Background/Aim. During peritoneal dialysis (PD) an exchange of substances between blood and dialysate takes place through specific histological structures of peritoneum. Peritoneal double-layered serous membrane has, so far, mostly been studied with electron microscopy on experimental animals. The aim of this study was to assess integrity of peritoneal tissue in end-stage renal disease (ESRD) and PD patients using standard light microscopy and immunohistochemical methods. Methods. Peritoneal tissue biopsies were performed on 25 persons: 8 healthy donors during nephrectomy, 9 ESRD patients upon insertion of PD catheter, and 8 PD patients upon removal of the catheter for medical indications. The samples were fixed and prepared routinely for immunocytochemical staining by standardized streptavidin biotin AEC method using a LSAB2® HRP kit (Dako®, Denmark) for collagen IV and analyzed by light microscopy. Results. We observed mesothelial detachment from lamina propria, duplicated basement membrane and much thicker blood vessel walls in ESRD and PD patients, compared to healthy subjects. Differences in histological structure, emphasized with immunostaining, indicated pathological alterations of peritoneal tissue in the renal patients. Conclusions. Imunohistochemistry can be used in studying histological alterations of peritoneal tissue in ESRD and PD patients. This method may indicate possible problems in filtration and secretion processes in this tissue.

Introduction. Incontinentia pigmenti (IP) is a rare complex X-linked genodermatosis in which skin changes are combined with anomalies of other organs. Mutations of the NEMO gene localized on chromosome Xq28 are responsible for IP. Clinical manifestations of IP according to evolution and prognosis can be considered as skin changes and dental, eye and central nervous system changes. Objective. The aim of our study was to investigate type and frequency of ocular features in Serbian population. Methods. We investigated the total of 9 families with 22 subjects, 20 females and 2 males, at the Institute of Dermatovenerology, Clinical Centre of Serbia, in the period from 1989 to 2009. Our subjects were diagnosed clinically by a dermatologist and the diagnosis confirmed by cutaneous histopathology and ultrastructural analysis. The pedigrees, karyotype analyses, routine laboratory findings, additional specialized clinical examinations were done for all subjects. Results. Among 22 IP patients from our study, different ophthalmological anomalies were observed in 16% of subjects. In female subjects, all of them with clinical characteristics of IP, we observed the following anomalies: retinal detachment, microphthalmia, cataract, strabismus and nystagmus. Conclusion. Compared to available literature data, our percentage of IP patients with anomalies was lower. It may be due to differences in examined populations or due to the fact that the patients in our study were firstly admitted to the Institute of Dermatology. Ophthalmological findings may be often considered as very severe anomalies in IP. It is very important to detect IP as early as possible, medically help and monitor these patients.

Introduction. Incontinentia pigmenti (IP) is an X-linked genodermatosis in which skin changes are combined with dental, eye and central nervous system anomalies. Objective. The goal of the study was to analyze ocular findings, IP minor criteria in available literature concerning IP cases published until now. Methods. We have done meta-analysis of 1931 IP patients found in 302 references published until 2010. Comparison of data published for the 1906-1976 and 1976-2010 periods was made. The collected data were mainly frequencies of ocular anomalies. Chi-square test was used to compare observed frequencies with their expectations. Results. Of total number of IP patients, 1,227 were ophthalmologically investigated. In 449 such patients 972 eye anomalies were registered, 2.16 anomalies per patient. Proportion of ophthalmologically investigated IP patients in the period 1906-1975 (70%) was higher than corresponding proportion (60%) for the period 1976-2010. For 1906-2010 period 36.5% IP patients with eye anomalies were diagnosed. The number of amaurotic eyes per patient did not significantly differ for the two periods (p=0.50; >0.05). The total number of eye anomalies per patient significantly differed for the same periods (p=0.00005;

Background. Incontinentia pigmenti (IP) is a rare, complex, X-linked genodermatosis in which skin changes are combined with defects of other organs. It appears almost exclusively in females and is usually lethal in men. It is estimated that according to the available reported cases, there have been approximately 900-1 200 affected individuals, out of which 60 males. The aim of the study was to report two additional individual male cases with IP. Case reports. We discovered two male patients with IP according to standard IP diagnostic criteria. The diagnosis was made by a dermatologist and confirmed by cutaneous histopathology and ultrastructural analysis. The pedigrees, karyotype analyses and routine laboratory findings were made. Two male probands were the only ones with IP in their families, with no history of miscarriages. Both probands had normal karyotype. In one proband, acrocentric chromosomes of the group D had tendency of forming associations. Histopathological and ultrastructural skin analyses revealed findings typical for IP. Conclusion. The detection of each male case is very valuable because of their rarity. Application of the standard diagnostic criteria is necessary for comparison and epidemiological analysis. Monitoring such probands allows a better determination of how genetic transmission occurs, and is important because of the different degrees of severity of IP.

Abstract The objective of this study was to present a systematic review of the central nervous system (CNS) types of anomalies and to consider the possibility to include CNS anomalies in Incontinentia pigmenti (IP) criteria. The analyzed literature data from 1,393 IP cases were from the period 1993–2012. CNS anomalies were diagnosed for 30.44% of the investigated IP patients. The total number of CNS types of anomalies per patient was 1.62. In the present study there was no significantly higher number of anomalies per patient in females than males. The most frequent CNS types of anomalies were seizures, motor impairment, mental retardation, and microcephaly. The most frequently registered CNS lesions found using brain imaging methods were brain infarcts or necrosis, brain atrophies, and corpus callosum lesions. IKBKG exon 4–10 deletion was present in 86.00% of genetically confirmed IP patients. The frequency of CNS anomalies, similar to the frequency of retinal anomalies in IP patients, concurrent with their severity, supports their recognition in the list of IP minor criteria.

Human inborn errors of thymic T cell tolerance underlie the production of autoantibodies (auto-Abs) neutralizing type I IFNs, which predispose to severe viral diseases. We analyze 131 female patients with X-linked dominant incontinentia pigmenti (IP), heterozygous for loss-of-function (LOF) NEMO variants, from 99 kindreds in 10 countries. Forty-seven of these patients (36%) have auto-Abs neutralizing IFN-α and/or IFN-ω, a proportion 23 times higher than that for age-matched female controls. This proportion remains stable from the age of 6 years onward. On imaging, female patients with IP have a small, abnormally structured thymus. Auto-Abs against type I IFNs confer a predisposition to life-threatening viral diseases. By contrast, patients with IP lacking auto-Abs against type I IFNs are at no particular risk of viral disease. These results suggest that IP accelerates thymic involution, thereby underlying the production of auto-Abs neutralizing type I IFNs in at least a third of female patients with IP, predisposing them to life-threatening viral diseases., (© 2024 Rosain et al.)

Incontinentia pigmenti (IP) is a rare skin disease combined with anomalies of the teeth, eyes, and central nervous system (CNS). Mutations of the IKBKG gene are responsible for IP. Among the most frequent CNS abnormalities found in IP using magnetic resonance imaging (MRI) are corpus callosum (CC) abnormalities. The aim of the study was to determine the presence of CC abnormalities, their relationship with the IKBKG mutations, and the possible presence of mutations of other genes. A group of seven IP patients was examined. Analyses of the IKBKG gene and the X-chromosome inactivation pattern were performed, as well as MRI and whole exome sequencing (WES) with the focus on the genes relevant for neurodegeneration. WES analysis showed IKBKG mutation in all examined patients. A patient who had a mutation of a gene other than IKBKG was excluded from further study. Four of the seven patients had clinically diagnosed CNS anomalies; two out of four had MRI-diagnosed CC anomalies. The simultaneous presence of IKBKG mutation and CC abnormalities and the absence of other mutations indicate that IKBKG may be the cause of CC abnormalities and should be included in the list of genes responsible for CC abnormalities.

Rare diseases represent a diagnostic challenge due to their number, variety of clinical phenomena, and possibility of a simultaneous presence of two or more diseases. An illustration of this challenge is an occurrence of a late diagnosis of a proband initially diagnosed with West syndrome, later revealed to be caused by Incontinentia pigmenti (IP). Furthermore, 20 years later, it was discovered that the proband was also a carrier of a heterozygous GBA gene mutation. The methods used in diagnostics were as follows: IKBKG gene analysis, the X-chromosome inactivation assay, analyses of the genes relevant for neurodegeneration, WES analysis, analysis of biochemical parameters typical for Gaucher disease (GD), and autoantibodies including IFN-α2a and IFN-ω. To avoid overlooking IP and other possible rare disease diagnoses, carefully searching for dermatological signs in these conditions is recommended. It is important that the diagnostic criteria are based on quality and extensive data from multiple studies of each rare disease. Establishing precise diagnostic criteria for as many rare diseases as possible and establishing a publicly accessible database of rare diseases with a search possibility according to phenotypic abnormalities and genetic mutations would greatly facilitate and speed up the establishment of an accurate diagnosis.

Introduction: Incontinentia pigmenti (IP) is a rare X-linked geno-dermatosis characterized by numerous findings. Skin biopsy and histopathological analysis are considered as minor criteria for the diagnosis of IP. We assume that dermoscopy can assist the earlier diagnosis of IP., Objectives: To gain experience in earlier diagnosis of IP by observing dermoscopic findings of cutaneous changes., Methods: We revised confirmed cases of IP and examined them using dermoscopy, comparing histopathological and dermoscopic results., Results: Stage I presented solitary and grouped vesicles in linear arrangement on erythematous skin. Early stage II presented star-shaped verrucous lesions on erythematous or pigmented skin. In well-developed lesions, dotted vessels surround keratotic part, some with thrombosed capillaries, resembling a viral wart. Stage III presented linear brown dots on the pigmented areas. Dermoscopic image was uniform in all the examined pigmented Blaschko linear changes. Stage IV presented numerous dotted vessels on the hypopigmented skin. Terminal hair was scarce or absent in all four stages. The surrounding normal skin had perifollicular depigmentations in stages III and IV., Conclusions: Dermoscopy of all four stages is very specific compared to the dermoscopy of inflammatory dermatoses and pigmentations. Stage III has very close clinical, histological and dermoscopic mimickers and needs to be carefully examined with obligatory genetic testing. Dermoscopy of the stage IV closely corresponds to histopathological findings and may be crucial as a quick tool in revealing potential IP gene carriers. Dermoscopy should be used in addition to clinical examination since the two methods are complementary., Competing Interests: Competing interests: None., (©2022 Minic et al.)

In X-chromosome-linked skin disorders the pattern of involvement follows Blaschko lines. Patterns of changes analogous to cutaneous Blaschko lines in different X-linked diseases existed in other organs. There is no commonly accepted analogy to Blaschko lines in the central nervous system (CNS). The objective of this study was to consider a hypothesis of the existence of Blaschko lines in the CNS in the example of incontinentia pigmenti (IP). Articles were analyzed in which brain imaging methods were used in IP patients with CNS anomalies. In IP patients with neurological signs brain lesions usually were localized and extended radially. Affected areas did not correspond to territories vascularized by any determined artery. Radially distributed brain lesions morphologically match the radial unit model of cortical development. It can be proposed that in IP in CNS Blaschko line analogies, similar to those in the skin, represent the trace of development of the clone of neurons arising from the cell marked with IKBKG mutation. The hypothesis of the existence of Blaschko line analogies in CNS is supported by radially distributed CNS image findings in IP, the radial unit model of CNS development, and the common embryonic origin of skin, CNS, and eyes., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Objectives: Incontinentia pigmenti (IP) is an X-linked genodermatosis caused by a mutation of the IKBKG gene. The objective of this study was to present a systematic review of the dental and oral types of anomalies, to determine the total number and sex distribution of the anomalies, and to analyze possible therapies., Materials and Methods: We analyzed the literature data from 1,286 IP cases from the period 1993-2010., Results: Dental and/or oral anomalies were diagnosed for 54.38% of the investigated IP patients. Most of the anomaly types were dental, and the most frequent of these were dental shape anomalies, hypodontia, and delayed dentition. The most frequent oral anomaly types were cleft palate and high arched palate. IKBKG exon 4-10 deletion was present in 86.36% of genetically confirmed IP patients., Conclusions: According to the frequency, dental and/or oral anomalies represent the most frequent and important IP minor criteria. The most frequent mutation was IKBKG exon 4-10 deletion. The majority of dental anomalies and some of the oral anomalies could be corrected., Clinical Relevance: Because of the presence of cleft palate and high arched palate in IP patients, these two anomalies may be considered as diagnostic IP minor criteria as well.

One of interesting aspects in dermatology is the fact that skin may reflect the presence of anomalies in other organs and tissues. One such example is incontinentia pigmenti (IP), a rare, complex, X-linked genodermatosis. Clinical manifestations of IP according to evolution and prognosis can be considered as skin, as well as dental, eye, and central nervous system, changes. We have investigated a total of nine families with 25 subjects, 23 females and 2 males. In 12 female and 2 male subjects, all of them with clinical characteristics of IP, we observed the following abnormalities: teeth-shape anomalies (coni- or peg-like teeth), the presence of numerous cariotic teeth, early dental loss, delayed eruption, partial anodontia, and gothic palate. To our knowledge, this is the first time that the presence of gothic palate in patients with IP has been documented. As we found out, in two female subjects and one male subject, in which nonrandomed X inactivation did not occur, gothic palate could be supposed as characteristic of IP.

The introduction of peritoneal dialysis (PD) as a respectable modality of renal replacement therapy some three decades ago, suddenly drew attention of many authors to peritoneal membrane as insufficiently investigated structure. In order to explain the pathological changes in peritoneum due to renal diseases, it became necessary to explore the normal peritoneal structure. The aim of this study was to examine the morphology of peritoneal lining cells in healthy persons. Biopsies of the peritoneum were performed on 20 volunteer kidney donors. Tissue samples were taken during renal transplantation. Special care was taken in getting appropriate samples without artificial damage because of the extreme fragility of the peritoneal tissue. The preparing procedure was standard for routine HE staining and for plastic embedded semifine and fine sections studies. Semifine sections were made on ultramicrotome, stained with Toluidin blue and studied by light microscope, while fine sections were made by ultramicrotome and studied by transmission electron microscope. One layer of cuboidal or flattened lining cells present over the lamina propria connective tissue presented mesothelium. The cells were overlapped like tiles on the roof. Lateral parts of their interdigitated membranes were interconnected with different types of cell junctions: unpermeable, adhesion and communication junctions; inhibiting intercellular transport. Cell surface was often covered with great number of microvilli and lamellar bodies. A single kinocilia was also often present on apical cell surface. Nuclei were euchromatic with well developed nucleoli. Cytoplasm was filled with a great number of ribosomes, mitochondria, cisterns of rough endoplasmatic reticulum and Golgi apparatus, lamellar bodies and lipid inclusions. Numerous pinocytic vesicles on all parts of the membrane as well as in the cytoplasm indicating active endocytosis, egsocytosis and transcytosys in the process of secretion and reabsorption of serous liquid in peritoneal cavity, were visible. Euchromatic nuclei with prominent nucleoli and numerous mitochondria indicate cells of great metabolic activity.

Introduction: Some thirty years ago peritoneal dialysis (PD) became a respectable modality of renal replacement therapy. That is why peritoneal membrane attracted interest of investigators. Certain changes, known as uremic serositis, appear in morphology of serous membranes in end stage kidney disease (ESKD). The aim of our investigation was to examine the morphology of peritoneal lining cells in control group of healthy persons and morphology of peritoneal lining cells in patients on PD., Material and Methods: Peritoneal biopsies were taken in 10 healthy volunteers during the kidney donation and in 15 patients on PD during clinically indicated extirpation. Biopsy samples were prepared for standard routine HE staining and for plastic embedded fine sections studying. Sections were mounted in an ultramicrotome, stained with Toluidine blue (TB) and studied by light microscope (SM), while fine sections were mounted in an ultramicrotome and studied by transmission electron microscope (TEM)., Results: One layer mesothelium of the cuboidal or flattened lining cells were present over the lamina propria connective tissue. Mesothelial cells were overlapped like tiles on the roof. These cells were interconnected with different types of cell junctions (unpermeable, adhesion and communication junctions) positioned on lateral parts of the interdigitated cell membranes. A great number of microvilli were often present on the appical surface, as well as a kinocilia and lamellar bodies. Nuclei were euchromatic with well developed nucleoli. Many ribosomes, mitochondria, cisternae of rough endoplasmic reticulum (RER) and Golgi apparatus, lamellar bodies and lipid inclusions were present in the cytoplasm. Using TEM in analyzing fine sections of biopsies of patients on PD, characteristic ultrastructural changes including epithelial defects with only remaining parts of destroyed cells were established, as well as significantly greater number of rough endoplasmic reticulum (RER) cisternae and immature mesothelial cells in lamina propria indicating intensive regeneration of this epithelium. The cytoplasm of new mesothelial cells were of less electron density on TEM photomicrographs, whereas the nuclei of mesothelial cells in these patients were euchromatic with prominent nucleoli and numerous perichromatic granules and fibrogranular nuclear bodies, indicating cells of great activity. Cytoplasmic protrusions of different shape and content were often recognized on the apical surface of cells. Lamellar bodies were also present in this group of patients within the mesothelial cells, as well as between two mesothelial cells or on their apical surface. Mitochondria were picnotic in many of the mesothelial cells of peritoneum in this patient group. In these mesothelial cells intracytoplasmic paracrystaline inclusions were established. TEM photomicrographs showed basal lamina multiplication in this epithelium., Conclusion: Our findings comply with reports of other authors. It should be stressed that TEM examination detects characteristic ultrastructural changes in mesothelial lining cells of peritoneum in patients on PD, which could compromise the function of peritoneum as a membrane for dialysis.

Objective: Uremia is known to be followed by changes in the serous membranes of pleura, pericardium, and peritoneum. During continuous ambulatory peritoneal dialysis (CAPD), the peritoneum is exposed to altered body conditions as well as to the influence of dialysate. The aim of the present study was to examine the ultrastructure of the mesothelial cells in CAPD patients, and to compare the findings with those from studies of the peritoneum in uremic controls. Paracrystalline intracytoplasmic inclusions in mesothelial cells were objects of special interest., Methods: Biopsies of human parietal peritoneum were studied. These were taken from 12 uremic patients during catheter implantation before the start of CAPD, and from 7 CAPD patients during catheter removal for infection or malfunction. The samples were prepared in the standard way to be studied by transmission electron microscopy (TEM)., Results: Paracrystalline intracytoplasmic inclusions were seen in mesothelial cells only by TEM. They appear as filamentous structures at the outer part of the inclusions, and as pearl-like structures at the core of the inclusions. Sacculate dilatations of rough endoplasmic reticulum cisternae with partly destroyed membranes and only few ribosomes were also seen, with and without densely osmiophilic filaments within the cisternae. We have found paracrystalline intracytoplasmic inclusions in mesothelial cells from uremic and CAPD patients both. According to the literature, these changes are present in one third of biopsies from uremic patients. Until now, however, they have not been mentioned in CAPD patients.

Some thirty years ago, peritoneal dialysis (PD) became a respectable modality of renal replacement therapy. That is why peritoneal membrane attracted the interest of investigators. Uremia is followed by changes in the morphology of serous membranes (uremic serositis). Uremic effects on pleura and pericardia have been studied for a long time, but the peritoneum is affected as well. The aim of our study was to examine the morphology of the peritoneum in uremic patients before the start of PD and to compare the findings with those from examinations of peritoneum in healthy controls. We examined 12 uremic patients and 10 healthy controls (kidney donors). Biopsies were taken from parietal peritoneum. The samples were prepared in the standard way for study by transmission electron microscopy (TEM). Certain pathological changes--deformation of mesothelial cells, their detachment from the basement membrane, and unusual bulging of apical surface--were identified at the light microscopy level on semi-fine sections. Paracrystalline intracytoplasmic inclusions were seen in mesothelial cells only by TEM. We hypothesize that the inclusions were causing deformation of the mesothelial cells and detachment of those cells from the basement membrane. Sacculate dilatations of rough endoplasmic reticulum (RER) cisternae with partly destroyed membranes and few ribosomes were also seen, with and without densely osmiophilic filaments within cisternae. Although these changes are mentioned in the literature, the exact reason for their appearance remains unknown.

The mechanisms of Golgi impregnation of neurons has remained enigmatic for decades. Recently, it was suggested that divalent (di)chromate anions play a role in the Golgi impregnation process. Therefore, we incubated slices of (para)formaldehyde-fixed rat brain tissue in solutions of potassium (di)chromate, phosphate, chloride or nitrate at pH 6 or 7. Slices were then immersed in solutions of silver nitrate and processed for light microscopical analysis. At pH 6, dichromate probes resulted in dense and homogeneous impregnation of neuronal cytoplasm (typical impregnation). At pH 7, chromate probes showed solely partial cytoplasmic and heavy nuclear-region neuron impregnation (atypical impregnation). Phosphate probes at pH 6 resulted in typical impregnation, whereas at pH 7 phosphate probes gave atypical impregnation. Both at pH 6 and 7, chloride and nitrate probes did not yield any Golgi impregnation. These findings confirmed the pH-dependence of silver-chromate Golgi impregnation as well as the correctness of corresponding acidic silver-phosphate impregnation. Our study revealed a previously unknown, strong anion-dependence of Golgi impregnation, suggesting that hydrogenated monovalent anions are carriers of the neuron impregnation.

Proliferative activity of tumors is strongly associated with prognosis and response to therapy. The reason for faster and uncontrolled growth rate of tumors compared with normal tissue may be caused by the greater proliferation of cells, the smaller rate of cell death, or both. Cell production vs. cell loss rates, and their correlation with a grade of tumor cell differentiation (G) was estimated in 45 cases of squamous cell lung cancers (SCLC) by the use of mitotic indices (MI), number of interphase NORs, and apoptotic indices (AI) as parameters. The mitotic figures as well as apoptotic cells were observed on paraffin sections (4-microm thick) stained with haematoxylin and eosin, and with Feulgen reaction with Schiff-type reagent containing 0.5% Toluidine Blue. According to our results, all three parameters distinguish significantly (P < 0.05) between well and moderately or poorly differentiated groups, but not between the first two groups, and clearly discriminate between low- and high-grade malignancy. These results suggest classification of squamous cell lung cancers into two groups, a group of low and a group of high proliferative activity, despite their morphological appearance. Regression analysis revealed a significant (P < 0.0005) correlation between MI and AgNOR counts per cell nucleus as proliferative markers and AI as a marker of cell loss. The number of mitoses and apoptoses, especially when they are expressed as a percentage of the total number of tumor cells, are markers of tumor proliferation rate. They both can be used in biofunctional staging, based on cell kinetics, to provide more prognostic information about lung cancers than clinicopathological staging.

Pseudoplatelets are the cytoplasmic fragments in the size of platelets originated not from megakaryocytes but from other blood cells which were observed in some patients with leukemia and infection. The clinical importance of pseudoplatelets is manifested in the falsely increased number of platelets in these patients. Transmission electron microscopy was used in the cytologic examination of 23 patients with different types of acute leukemia. The presence of pseudoplatelets in the form of budding of the cytoplasm of the granulocytic, monocytic and lymphocytic strains of various maturity has been shown.

The presence of myocardial bridges over the coronary arteries has been studied in 29 monkey (Cercopithecus aethiops) hearts. The great resemblance between the Cercopithecus subepicardial arterial net with the corresponding one in humans has been revealed. There is a high incidence (83%) of myocardial bridges only over the ventricular branches of both coronary arteries. Myocardial bridges are usually (90%) located over the left coronary artery branches, and the left anterior interventricular branch is the most frequently (69%) overbridged vessel. The bridges are always single over the vessel examined and their length varies from 0.5 mm to 31.6 mm. No statistically significant sexual difference in myocardial bridges distribution is reported.

The problem of provenance of the mature granulocytes in acute myeloblastic leukemia (AML) and in acute lymphoblastic leukemia in their active phase and in remission is still completely unresolved. Mature granulocytes could possibly arise in acute phase of AML from the remaining normal möelopoietic or granulopoietic stem cell or from the very leukemic clone of stem cell which still display, at least partially, the ability to sustain maturation to normal granulocyte level. In ALL, mature granulocyte probably arise from normal granulocyte precursors. In remitted AML, according to opinions of a majority of authors, mature neutrophils descend from normal stem cells. Following the study of 19 patients with AML and 19 patients with ALL, by utilizing the morphological, cytochemical and cytoenzymic properties of granulocytes et the light and electronomicroscopic level the authors have concluded: (1) in comparison with normal granulocytes, granulocytes show in the active AML, hypogranularity as well as a decrease in the activity of all studied enzymes (myeloperoxidase, alkaline and acidic phosphatase and the esterases). (2) In ALL, mature granulocytes do not feature any particular differences in the above pattern as compared with normal granulocytes. (3) In AML remission, the difference between the mature granulocytes and the granulocytes in the active disease is rather slight as compared with the morphological, cytochemical an cytonzymic characteristics. The authors conclude that in a number of patients with AML and in the remitted patients mature granulocytes could possibly originate from the leukemic stem cells which acquired the ability to respond to normal CSF by manner of the gross destruction of the leukemic tumour mass.(ABSTRACT TRUNCATED AT 250 WORDS)