Evaluation of absolute volume of human fetal kidney's cortex and medulla during gestation

Background. Human fetal kidney is quite different from the mature kidney, both macroscopically and hystologically. Lobulated surface of the human fetal kidney reflects its inner organization. Aim. To determine the fetal kidneys' volume according to the gestational age, to establish periods of their maximal and minimal growth and to compare these values for various gestational ages. Methods. Forty five human fetal kidneys aged from IV to X lunar months were analyzed. Kidneys were divided into nine groups according to their gestational age. The volumes of cortex and medulla were determined using stereological methods. The results were statistically analyzed and the periods of significant growth of these structures were marked. Results. Fetal kidney's cortex and medulla grew continually with a very high coefficient of linear correlation with crown-rump length. The cortex/medulla ratio was minimal in the first half of V lunar month, when medulla grew most rapidly and it was maximal immediately before birth, when cortex achieved its maximum. Conclusion. This study was an effort to provide some parameters which would help in the future investigations of the development of human fetal kidney

Possible Therapeutic Use of Spermatogonial Stem Cells in the Treatment of Male Infertility: A Brief Overview

Development of germ cells is a process starting in fetus and completed only in puberty. Spermatogonial stem cells maintain spermatogenesis throughout the reproductive life of mammals. They are undifferentiated cells defined by their ability to both self-renew and differentiate into mature spermatozoa. This self-renewal and differentiation in turn is tightly regulated by a combination of intrinsic gene expression as well as the extrinsic gene signals from the local tissue microenvironment. The human testis is prone to damage, either for therapeutic reasons or because of toxic agents from the environment. For preservation of fertility, patients who will undergo radiotherapy and/or chemotherapy have an attractive possibility to keep in store and afterwards make a transfer of spermatogonial stem cells. Germ cell transplantation is not yet ready for the human fertility clinic, but it may be reasonable for young cancer patients, with no other options to preserve their fertility. Whereas this technique has become an important research tool in rodents, a clinical application must still be regarded as experimental, and many aspects of the procedure need to be optimized prior to a clinical application in men. In future, a range of options for the preservation of male fertility will get a new significance

ABSOLUTE AND RELATIVE RENAL LENGTH IN CHRONIC KIDNEY DISEASES

The aim of the paper is to evaluate the significance of absolute and relative renal length in the diagnoses of several chronic kidney diseases (CKDs) in which kidney size changes in different manners during the disease course. The study included 181 patients: 35 with Balkan endemic nephropathy (BEN), 31 with diabetic nephropathy (DN), 30 with primary glomerular diseases (GN), 30 with autosomal recessive polycystic kidney disease (ADPKD), and 58 healthy controls (C). Absolute renal length was the distance between two most distant points on their poles and it was measured ultrasonographically, and relative length was obtained as the ratio of renal length and body height (kidney/body ratio, KBR). In the statistical analysis, One Way ANOVA test was used to establish the differences in absolute lengths and KBR between the studied groups; 2 test was used to establish the differences in the number of examinees of male and female gender; correlation and linear regression analysis were used to assess the association between age of the examinees and absolute and relative parameters of kidney size. The obtained results demonstrated that the average lengths of the right and left kidney were highest in ADPKD and lowest in BEN group. The average values of KBR of the right and left kidney showed a trend similar to that of average absolute lengths in all groups, except in GN and DN groups, in which absolute parameters of kidney size differed significantly from relative parameters. The correlation analysis showed that a significant negative correlation between age and absolute i.e. relative parameters of kidney size existed only in BEN group, but even in this case the differences between correlation coefficients of absolute and relative length of both kidneys were not statistically significant. Based on the obtained results, we could not establish the advantage of absolute over relative kidney length and vice versa in the studied CKDs. Further studies of larger patient samples with better gender and age distribution are therefore warranted

MORPHOMETRIC CHARACTERISTICS OF NEPHRITIC SINUS AND PARECHYME DURING THE AGEING PROCESS IN HUMAN

The ageing of organism is a continues proces manifested by changing in every tissue and organ. The progressing of ageing is associased with many changes in macroscopic look, structure and function of kidney.Considering the literature data on the importance of healthy kidney in function of organism, we want to bind the ageing process in a healthy kidney with changes in nephritic sinus and parenchyme brought by ageing.The investigation is done on 50 fresh sampels of postmortal adult human kidneys without and kidney disease found. On the frontal section the dimensions of sinus were defined (longitude and width) as well as dimensions of parenchyme (width of cortex and medula) on the left and right kidney. We devided tissue sampels in six ageing categories: I (20-29); II (30-39); III (40-49); IV (50-59); V (60-69) and VI (more then 70 years).The dimensions of left and right nephritic sinus show tendency of continuing increase from I to VI ageing group with statistically significant difference in sinus width (p<0,05), between I and VI ageing group while the difference in longitude was (p<0,01) between I and IV and (p<0,05) between I and V and VI. The width of cortex and medulls of kidney parenchyme doesn’t show any statistically significant difference in V to I and in VI to V ageing group (p<0,01).It is evident that dimensions of nephritic sinus increase during thickning of kidney parenchyme which causes reduction of whole kidney

TERRITORIAL INVESTIGATION OF DONJA TRNAVA VILLAGE AS ENDEMIC AREA 22 YEARS

Endemic nephropathy is a renal disease of unknown aetiology, which occurs endemically and affects individuals from risk families, with latent but progressive natural course and fatal outcome. In earlier territorial investigations, endemic areas were found along the Juzna Morava River: Brestovac, Kutles, Trupale, Gornja i Donja Toponica, Luzane, Nozrina, Moravac and other settlements. The last extensive studies of endemic nephropathy in these villages were conducted in 1981. These investigations showed that 2.7% of inhabitants along the right side of Juzna Morava River, in Donja Trnava village, suffered from endemic nephropathy. In the present study, a total of 291 persons (153 female and 138 male), aged 7 to 77, were investigated. Diagnosis of endemic nephropathy was made according to the natural history, physical examination and urine analysis. Two persons or 0.68 % (one with chronic renal failure, and the other with an end-stage renal disease, on haemodialysis treatments) had endemic nephropathy. Eight persons (or 2.75%) suffered from other renal diseases. There were no urothelial tumors, which was confirmed in previous studies. Based on these investigations, a total of 39 persons from 29 risk families was selected for further examinations and following-up at the Institute of Nephrology and Haemodialysis in Nis

ULTRASOUND EXAMINATION OF THE RENAL CORTEX IN THE HEALTHY NEW-BORN

The examination of the kidney parenchyma by the ultrasound assumes the identification of the cortex, of the medulla and of the arciform blood vessels. The kidney cortey is normally less echogenic than the parenchyma of the spleen and the liver; in the normal new-borns and babies it can also be isoechogenic with the liver parenchyma while in the prematures and in the new-borns with a small delivery mass it can be even more echogenic than the liver parenchyma. In the parenchymic diseases of the children kidneys the cortex becomes more echogenic than the liverparenchyma or it can be isoechogenic with it. The aim of the paper is to examine the kidney cortex isogenic nature in healthy new-borns of different age and body mass. The examination comprised 49 healthy new-borns with the normal urine findings as well as the normal nitrogen products in the serum of the age from 1 to 27 days with the body mass from 1900 to 4950 g. The real time ultrasound technique was used as adopted to the new-born age. It was found out that the kidney cortex of the majority of the healthy new-borns - born on time with a small delivery mass - as well as that of the prematures was isoechogenic with the liver parenchyma or more echogenic than it. In the new-born with a delivery mass of over 3000 g and especially of over 4000 g the kidney cortexwas most often more hypo-echogenic than the liver parenchym

APOPTOSIS DURING HUMAN FETAL KIDNEY DEVELOPMENT

Kidney morphogenesis is a complex and stepwise process. The formation of mature kidney in mammals is preceded by two primitive embryonic kidneys known as pronephros and mesonephros. Metanephros develops as a result of reciprocal inductive interactions between two primordial mesodermal derivates: ureteric bud, an epithelial outgrowth of the Wolffian duct, and metanephric blastema, a group of mesenchymal cells. The ureteric bud induces the metanephric mesenchyme to differentiate and form nephrons, whilst the metanephric mesenchyme induces the ureteric bud to grow and branch to form collecting ducts. The nephron goes through four developmental stages, which are described as: 1) vesicle, 2) comma-shaped and S-shaped stages, 3) developing capillary loop, and finally 4) maturing glomerulus. Apoptosis (programmed cell death) is a predominant form of physiological cell death, by which organism eliminate unwanted or damaged cells. It is the major component of normal development and disease. Apoptosis is the result of series of biochemical processes happening in certain order in a dying cell, among which the most important is activation of enzyme families called caspases which influence different cell components. Apoptosis is characterized by membrane blebbing, shrinkage of the cell, nuclear fragmentation and chromatin condensation. Organelles are preserved almost intact. Cell surface molecules change. A variety of physiological and pathological stimuli can initiate apoptosis. They act via receptor mechanisms, through biochemical agents, or cause DNA and cell membrane damage. Apoptosis is an important component of fetal development. It is thought that apoptosis is the one of the main regulatory events involved in kidney morphogenesis, considering that among great number of developed cells, only a few of them are involved in the developing program by escaping apoptosis. In any period during kidney development about 3 to 5%of cells are apoptotic. Thorough elucidation of the regulators controlling apoptotic pathways during development may contribute to the development of therapeutic agents that can prevent onset of developmental abnormalities of the kidney

Changes of the glomerular size during the human fetal kidney development

Introduction. Newborns adaptation on postnatal conditions includes significant morphological and functional renal changes. Every kidney contains a constant number of nephrons, at the end of the nephrogenesis period, which extends from week 8 to 34 of gestation. Mature juxtamedullary nephrons possess higher filtration capacity than primitive superficial nephrons, which have insufficient vascularization. Objective. The objective of the study was to calculate an average glomerular diameter in cortical zones of the kidney during development, to define periods of their most intensive growth, and to record differences of glomerular size between different cortical zones. METHOD A total of 30 human fetal kidneys aged from IV to X lunar months were analyzed. Stereological methods were used for calculating the average glomerular diameter in superficial, intermediate and juxtamedullary zone of the kidney cortex. Results. Glomeruli in the superficial cortical zone had the lowest average diameter. The average glomerular diameter continually increased from IV lunar month (0.057±0.004 mm) to X lunar month (0.082±0.004 mm), with highly significant correlation with gestational age (r=0.755; p&lt;0.01). The average glomerular diameter in the intermediate zone increased from 0.081±0.004 mm (IV lunar month) to 0.096±0.004 mm (X lunar month) with low linear correlation with gestational age (r=0.161). Juxtamedullary glomeruli were the biggest ones. Their average diameter, during the IV LM ranged from 0.093±0.006 mm to 0.101±0.004 mm. In the newborns (X lunar month), juxtamedullary glomeruli had spherical structures with an average diameter of 0.103±0.004 mm, and low negative correlation (r=-0.032) with gestational age. In the IV and V lunar months of gestation, there was significant difference (p&lt;0.01; p&lt;0.05) between the average glomerular diameter in the different zones of the kidney cortex. Conclusion. Superficial glomeruli had the smallest diameter, while juxtamedullary glomeruli were the largest. The average glomerular diameter increased during intrauterine development in all zones, most intensive in the X lunar month. There was a significant difference of the glomeruli between different cortical zones in the young fetuses. Such significant difference receded as gestational age increased

HUMAN GLOMERULAR VOLUME QUANTIFICATIONDURING THE AGING PROCESS

Kidney function is directly related to the changes of renal tissue, especially glomeruli, which is particularly distinct during the aging process. The impossibility of kidney function substitution points to the need for glomerular morphologic and functional characteristics estimation during the aging process.Human cadaveric kidney tissue samples were used as material during research. Age of cadavers ranged from 20 to 70 years and they were classified according to the scheme: I (20–29); II (30–39); III (40–49); IV (50–59); V (60–69) i VI (older than 70). After the routine histologic preparation of the renal tissue the slices were analized stereologicaly under the light microscope with projection screen (Reichert Visopan) with 40 x lens magnification. M42 test system was used and 100, by unbased method selected glomeruli, were analyzed.Average glomerular capillary network volume shows significant increase (p< 0,001) as far as to the age of 50 years in regard to the age of 20 to 29 years. This parameter shows insignificant decrease after the age of 50 until the age of 70 years. This decrease was significant after the age of 70 years in regard to the period of the 20 to 29 (p< 0,05) and the period of 40 to 49 years (p<0,01)