Heritable testicular hypoplasia in Nguni (Bos indicus) bulls: vascular characteristics and testosterone production.

The biased unilateral occurrence of heritable gonadal hypoplasia was investigated by examining the gross- and microanatomy of the testicular artery and vein, testicular blood flow and testicular testosterone secretion in normal Nguni bulls and in Nguni bulls showing unilateral left, unilateral right and bilateral hypoplasia of the testis. A high incidence of branching of the testicular artery was found ipsilateral to hypoplastic testes. The branching occurs a short distance from the dorsal aorta: one branch proceeds to the testis, the other to the ipsilateral kidney. The association between arterial branching to the kidney and ipsilateral hypoplasia of the testis held for both unilaterally left and unilaterally right hypoplastic bulls. Variations in the anatomy of the testicular vein occurred in both normal and hypoplastic bulls but there was no specific association between the variations and ipsilateral hypoplasia. The lumen diameter of the testicular artery or branch correlated with testis mass. Wall thickness of the artery ipsilateral to hypoplastic testes was not different from that in normal bulls, discounting hyperplasia of the endothelium. Total blood flow to the testis correlated with testis mass. The secretion rate of testosterone from hypoplastic testes was lower than that of normal testes but there was no difference when compared on a unit mass basis.     

Lesions in mink (Mustela vison) infected with giant kidney worm (Dioctophyma renale).

Adult Dioctophyma renale occupied the enlarged renal pelvis of the right kidney of naturally infected mink. Lesions in the kidney parenchyma consisted of connective tissue proliferation in the interstitial tissue, tubular atrophy and fibrosis, and periglomerular fibrosis. The luminal surface of the renal pelvis wall was formed of numerous papillae covered with transitional epithelium. The nematodes in the lumen were bathed in an albuminous fluid containing red blood cells, epithelial cells and D. renale eggs. The left (uninfected) kidney was 60% larger than the left kidney of normal mink.     

Diphallia in a mixed-breed dog with multiple anomalies

Complete diphallia was detected in a six-month-old Poodle cross dog. Duplication of the urinary bladder, right renal hypoplasia, bifurcation of the descending colon and bilateral cryptorchidism were also present. The left urethra was patent, and emptied the left urinary bladder; the right urethra ended blindly at a point 2.5 cm from the tip of the right penis. The left urinary bladder was joined medially to a right urinary bladder with no interbladder communication; however, the right bladder opened caudally into a blind sac which drained into the left prostatic urethra. Pyelonephritis of the left kidney was present, and was suspected to be due to ascending bacterial infection of the right urinary bladder and the right segment of the bifurcated descending colon, which terminated at the apex of the right urinary bladder. Diphallia and associated urogenital anomalies are reviewed.     

Lymph node topography and various features of the metastasis of malignant kidney tumors

Due to investigations of 102 renal preparations performed on corpses of mature persons, topographic peculiarities of the lymph nodes, getting lymph from the left and right kidneys, are revealed. Every lymph node of the left kidney gets greater amount of lymphatic vessels than every node of the right kidney. The lymph, running from the right kidney, usually gets through a less number of the subsequently arranged nodes up to the thoracic duct, as compared to the lymph, that runs from the left kidney. A typical position for the node, which the renal lymphatic vessels get into, is the fatty tissue in the area of the angle formed by the aorta edge and the inferior wall of the corresponding renal artery. The lymphatic nodes of the right kidney are arranged in the fatty tissue more compact than the left ones. These peculiarities, revealed by morphological investigations, are proved by analysis of 114 case histories of persons suffering from malignant neoplasms in the kidneys.     

Gonadal agenesis in a 46,XY female with multiple malformations and positive testing for the sex-determining region of the Y chromosome.

A full-term 46,XY female newborn presented with respiratory failure due to a right-sided diaphragmatic hernia. During surgical repair, exploration revealed isolated dextrocardia and hypoplasia of the right lung. Neither gonads nor wolffian or müllerian structures could be palpated. Cardiac catheterization demonstrated defects of the ventricular septum, hypoplasia of the right pulmonary artery, persistence of the left vena cava superior and a patent ductus arteriosus. Anthropometric data were normal at birth, but fell below the 3rd percentile during follow-up. Body proportions displayed a predominance of the upper compared to the lower segment. Endocrine studies indicated no defect of steroid biosynthesis and no functional gonadal tissue. Using genetic analyses of various loci within the testis-determining region of the Y chromosome, a mutation could not be detected. The patient died from pneumonia at the age of 19 months. Postmortem examination confirmed the diagnosis of gonadal agenesis.     

A New Apparatus for Standardized Rat Kidney Biopsy

Survival biopsies are frequently applied in rat kidney disease models, but several drawbacks such as surgical kidney trauma, bleeding risk and variable loss of kidney tissue are still unsolved. Therefore, we developed an easy-to-use core biopsy instrument and evaluated whether two consecutive kidney biopsies within the same kidney can be carried out in a standardized manner. On day 0, 18 Lewis rats underwent a right nephrectomy and 9 of these rats a subsequent first biopsy of the left kidney (Bx group). 9 control rats had a sham biopsy of the left kidney (Ctrl group). On day 7, a second kidney biopsy/sham biopsy was performed. On day 42, all animals were sacrificed and their kidneys were removed for histology. Biopsy cylinders contained 57±28 glomeruli per transversal section, representing an adequate sample size. PAS staining showed that the biopsy depth was limited to the renal cortex whereas surgical tissue damage was limited to the area immediately adjacent to the taken biopsy cylinder. On day 42, the reduction of functional renal mass after two biopsies was only 5.2% and no differences of body weight, blood pressure, proteinuria, serum creatinine, glomerulosclerosis, interstitial fibrosis or number of ED-1 positive macrophages were found between both groups. In summary, our apparatus offers a safe method to perform repetitive kidney biopsies with minimal trauma and sufficient sample size and quality even in experimental disease models restricted to one single kidney.     

Treatment of hypoglossia-hypodactyly syndrome without extremeity anomalies

Three cases of hypoglossia-hypodactyly syndrome without limb deformities are reported. All exhibited different degrees of tongue hypoplasia, micrognathia, retrognathia with a very narrow space between the left and right halves of the mandible, constricted isthmus, and only one lower incisor. Bone lengthening for the midline mandibular hypoplasia and orthodontic treatment were performed in the three cases with satisfactory results.     

Kidney pseudotumour diagnosed by emission computed tomography.

Emission computed tomography is a new, useful imaging technique; when a rotating gamma camera capable of such imaging is used multiple adjacent transverse sections may be obtained simultaneously, from which coronal and sagittal sections may be computed. The technique was used in a man undergoing urological investigation in whom excretion urography indicated a space-occupying lesion in the left kidney. Ultrasonography and radionuclide imaging showed nothing abnormal, but emission computed tomography using a rotating gamma camera showed that functioning cortical tissue extended across the middle of the left kidney. Radiographs were therefore reviewed and ultrasonography repeated, and it was concluded that the abnormality was a hypertrophied column of Bertin. Emission tomographic imaging of the kidney is a useful adjunct to other non-invasive studies.     

Immunohistochemical localization of Pax2 and associated proteins in the developing kidney of mice with renal hypoplasia.

Pax2 has been identified as a key regulatory protein associated with renal developmental malformations. The purpose of this study was to determine whether Pax2 protein expression, and that of other proteins important for normal renal development, is abnormally distributed in the prenatal kidney of the Brachyrrhine (Br) mouse that displays heritable renal hypoplasia. Embryonic 3H1 +/+ and Br/Br mice were collected between E11.0 and E18.0. Routine light microscopy and immunohistochemical analysis using antibodies to Pax2, E-cadherin, fibronectin, laminin, and Type IV collagen were applied to sequential tissue sections. E-cadherin stained consistently in the renal tubules of both normal and mutant animals. Whereas the initial expression of Pax2 corresponded between normal and mutant kidneys, it became progressively limited to the nephrogenic zone in +/+ animals, while distributing erratically in the Br/Br kidney. Fibronectin was not expressed in the normal nephrogenic zone but remained abundantly distributed throughout the Br/Br kidney. Luminin and Type IV collagen staining revealed a deficiency in renal vasculature formation in Br/Br kidneys. Results suggest that initial morphological differentiation occurs normally in the Br kidney but that subsequent nephric formation is associated with abnormal distribution of Pax2 and ECM proteins. (J Histochem Cytochem 49:1081-1097, 2001)     

Thrombocytopenia-absent radius (tar) syndrome: a case with agenesis of corpus callosum, hypoplasia of cerebellar vermis and horseshoe kidney

The thrombocytopenia-absent radius (TAR) syndrome (MIM 274000) is a congenital malformation syndrome characterised by bilateral absence of the radii with present thumbs, hypomegakaryocytic thrombocytopenia and a number of additional features including skeletal and cardiac anomalies. Mental retardation, reported in about 7% of patients, is usually secondary to intracranial hemorrhage. In 1994 there was a single report of a girl with TAR syndrome and hypoplasia of the cerebellar vermis and corpus callosum and in 2003 another case of TAR syndrome with cerebellar dysgenesis has been reported. In 2000 there was first report of horseshoe kidney in association with TAR syndrome followed by a clinical study of 34 cases with TAR syndrome in 2002 where horseshoe kidney was noted in two cases. Here we report of a girl with TAR syndrome, severe mental retardation, agenesis of corpus callosum, hypoplasia of cerebellar vermis and horseshoe kidney. There is no previous report of a child with TAR syndrome and all those associated anomalies in the same patient.     

The ECM protein nephronectin promotes kidney development via integrin alpha8beta1-mediated stimulation of Gdnf expression

Development of the metanephric kidney crucially depends on proper interactions between cells and the surrounding extracellular matrix. For example, we showed previously that in the absence of alpha8beta1 integrin, invasion by the ureteric bud into the metanephric mesenchyme is inhibited, resulting in renal agenesis. Here we present genetic evidence that the extracellular matrix protein nephronectin is an essential ligand that engages alpha8beta1 integrin during early kidney development. We show that embryos lacking a functional nephronectin gene frequently display kidney agenesis or hypoplasia, which can be traced to a delay in the invasion of the metanephric mesenchyme by the ureteric bud at an early stage of kidney development. Significantly, we detected no defects in extracellular matrix organization in the nascent kidneys of the nephronectin mutants. Instead, we found that Gdnf expression was dramatically reduced in both nephronectin- and alpha8 integrin-null mutants specifically in the metanephric mesenchyme at the time of ureteric bud invasion. We show that this reduction is sufficient to explain the agenesis and hypoplasia observed in both mutants. Interestingly, the reduction in Gdnf expression is transient, and its resumption presumably enables the nephronectin-deficient ureteric buds to invade the metanephric mesenchyme and begin branching. Our results thus place nephronectin and alpha8beta1 integrin in a pathway that regulates Gdnf expression and is essential for kidney development.     

Biochemical compartmentation of gluconeogenic enzymes in fish tissues

Compartmentation of liver, kidney muscle and gill tissues in relation to glucose-6-phosphatase and fructose 1,6-diphosphatase was examined in the fishes Labeo rohita, Clarias batrachus and Channa punctatus. The anterior region of the right and left lobes of the liver contained the maximum of fructose 1,6-diphosphatase and glucose-6-phosphatase, while the minimum was in the right and left lobes of gill tissue. Herbivore fish had the highest gluconeogenic enzyme content followed by carnivore and piscivore species. The observed enzymatic variations in the three fish species were discussed.     

Activation of cardiorenal and pulmonary tissue endothelin-1 in experimental heart failure

Endothelin-1 (ET-1) is a peptide that has been implicated in congestive heart failure (CHF). Although increased concentrations of circulating ET-1 have been repeatedly demonstrated, the activation of local ET-1 in target tissues of CHF remains poorly defined. Our objective was to characterize ET-1 tissue concentrations and gene expression of prepro ET-1 in myocardial, renal, and pulmonary tissue in rapid ventricular pacing-induced canine CHF. Progressive rapid ventricular pacing (38 days) resulted in impaired cardiovascular hemodynamics, increased atrial and left ventricular mass, decreased renal sodium excretion, and increased ET-1 plasma concentrations (all P < 0.05). Tissue analysis revealed significant increases in local ET-1 during CHF in left ventricular, renal, and pulmonary tissue, whereas a moderate increase in left atrial ET-1 did not reach statistical significance. In contrast, prepro-ET-1 gene expression was increased more than threefold in pulmonary tissue and more than twofold in left atrial myocardium with no increase in left ventricular or renal gene expression. The present studies demonstrate a differential pattern of ET-1 activation in cardiorenal and pulmonary tissue with a strong accumulation of ET-1 in kidney and lung during CHF. Although the observed increase in left ventricular and renal ET-1 in association with unaltered gene expression is consistent with increased uptake, pulmonary and atrial tissue may contribute to increased circulating and local ET-1 in CHF.     

A comparative analysis of the persistence of capillary blood flow oscillations in the left and right rat kidneys

Several parameters of the nonlinear dynamics of blood flow oscillations were studied in the left and right rat kidneys in baseline conditions and a perturbed state. An intramuscular injection of aspirin in 0.9% saline (0.5 mg per 100 g body weight) was used as a perturbation factor. Capillary blood flow was measured at baseline and 50 min after the aspirin injection by laser Doppler flowmetry. The persistence of time series was estimated by the Hurst method. Baseline time series were persistent in the right kidney and nonpersistent in the left kidney. Aspirin-perturbed time series were persistent in both the right and left kidneys, but the Hurst index was significantly higher in the left kidney. The results showed that the microcirculatory bed of the right rat kidney is more stable to perturbation as compared with that of the left kidney.     

Experimental Dirofilaria immitis-associated glomerulonephritis induced in part by in situ formation of immune complexes in the glomerular capillary wall

Eight dogs were immunized with an aqueous-soluble extract of adult Dirofilaria immitis. Subsequent to at least 7-fold increases in antibody titer, the left renal artery of each dog was infused with 6 mg of D. immitis antigen. Fourteen days after infusion, the left kidney was compared to the right kidney and preinfusion biopsies. All dogs developed glomerular lesions in the left kidney characterized by 1 or more of the following: mesangial cell proliferation, neutrophil infiltration, increased periodic acid-Schiff-positive staining of the mesangium and glomerular basement membrane (GBM), fibrin deposition, and thickening of the GBM. Left kidney glomerular immunofluorescence was positive in 7 of the 8 dogs using polyclonal antisera for canine IgG and C3 in a linear or fine granular pattern. Ultrastructural lesions were present in the left kidney of all dogs and consisted of irregular GBM thickening, intramembranous and mesangial electron-dense deposits, and mesangial and endothelial cell proliferation. Antibodies directed against D. immitis antigen were demonstrated in all kidney eluates from the left kidney. The right kidneys of 3 of the dogs developed lesions; however, in comparison to the left kidney, the lesions in the right kidneys were inconsistent, mild, and focal. The histologic findings in the left kidney were similar to those observed in dogs with naturally occurring D. immitis infections. In sham-immunized control dogs, renal arterial infusion of D. immitis antigen did not cause consistent immune complex glomerulonephritis; however, antigen adherence to glomerular capillary walls was observed by immunofluorescent microscopy.(ABSTRACT TRUNCATED AT 250 WORDS)     

Metabolic effects of long-term diversion of renal venous blood into the portal system

In 7 splenectomized dogs a left renal vein-splenic vein anastomosis was performed and the right kidney removed. Eighteen to twenty-four months after portalization of renal venous blood no significant alterations of liver function tests were observed. Long-term diversion of renal venous blood into the liver was followed by a slight increase of creatinine and 25-OH-D, a decrease of alpha-amino acid nitrogen in blood plasma and of plasma renin activity in peripheral blood, by signs of slight carbohydrate intolerance despite hyperinsulinaemia, and a slight decrease of erythrocyte count. No influence of this procedure on plasma proteins, lipids, electrolytes, aldosterone and cortisol was found. No morphological abnormalities in the liver and kidney tissue were found.     

Alk3 controls nephron number and androgen production via lineage-specific effects in intermediate mesoderm

The mammalian kidney and male reproductive system are both derived from the intermediate mesoderm. The spatial and temporal expression of bone morphogenetic protein (BMP) 2 and BMP4 and their cognate receptor, activin like kinase 3 (ALK3), suggests a functional role for BMP-ALK3 signaling during formation of intermediate mesoderm-derivative organs. Here, we define cell autonomous functions for Alk3 in the kidney and male gonad in mice with CRE-mediated Alk3 inactivation targeted to intermediate mesoderm progenitors (Alk3(IMP null)). Alk3-deficient mice exhibit simple renal hypoplasia characterized by decreases in both kidney size and nephron number but normal tissue architecture. These defects are preceded by a decreased contribution of Alk3-deleted cells to the metanephric blastema and reduced expression of Osr1 and SIX2, which mark nephron progenitor cells. Mutant mice are also characterized by defects in intermediate mesoderm-derived genital tissues with fewer mesonephric tubules and testicular Leydig cells, epithelial vacuolization in the postnatal corpus epididymis, and decreased serum testosterone levels and reduced fertility. Analysis of ALK3-dependent signaling effectors revealed lineage-specific reduction of phospho-p38 MAPK in metanephric mesenchyme and phospho-SMAD1/5/8 in the testis. Together, these results demonstrate a requirement for Alk3 in distinct progenitor cell populations derived from the intermediate mesoderm.     

Lung hypoplasia in the nitrofen model of congenital diaphragmatic hernia occurs early in development

The teratogen nitrofen produces a congenital diaphragmatic hernia (CDH) and pulmonary hypoplasia in rodent fetuses that closely parallel observations made in humans. We hypothesized that these changes may be due to primary pulmonary hypoplasia and not herniation of the abdominal contents. Timed-pregnant rats were given nitrofen on day 9, and fetuses were harvested on days 13 through 21. Initial evagination of lung buds on gestational day 11 was not delayed in nitrofen-treated fetuses. On gestational day 13, however, there was a significant decrease in the number of terminal end buds in the lungs of nitrofen-exposed fetuses vs. controls. Thymidine-labeled lung epithelial and mesenchymal cells were significantly decreased in nitrofen-treated lungs. Lungs from nitrofen-treated fetuses exhibited wide septae with disorganized, compacted tissue, particularly around the air spaces. Expression of surfactant protein B and C mRNAs was significantly decreased in the nitrofen litters. In situ hybridization of fetal lung tissue at all gestational ages showed no difference in the expression of vascular endothelial growth factor, Flk-1, or Flt-1 mRNAs. Because closure of the diaphragm is completed on gestational day 16 in the rat, our results suggest that lung hypoplasia in this model of CDH is due at least in part to a primary effect of nitrofen on the developing lung.     

Fine needle aspiration biopsy of primary renal synovial sarcoma. A case report

BACKGROUND: Primary renal synovial sarcoma is a relatively recently described and characterized neoplasm, formerly designated embryonal sarcoma of the kidney, and has not been diagnosed before by fine needle aspiration biopsy cytology. We describe the cytologic features of a malignant biphasic neoplasm of the kidney that was subsequently diagnosed at nephrectomy and confirmed with molecular genetic analysis as a biphasic renal synovial sarcoma. CASE: A 38-year-old male presented with acute abdominal pain. Computed tomography (CT) demonstrated a 4.7-cm mass in the left kidney. No soft tissue or extrarenal masses were identified. A CT-guided fine needle aspiration biopsy revealed a malignant biphasic tumor characterized by minimally atypical tubular epithelium, immature spindle cells and foci of coagulative tumor necrosis. At nephrectomy, a necrotic, pseudo-encapsulated synovial sarcoma of the upper pole of the left kidney was identified and was additionally evaluated with immunohistochemistry and molecular genetic studies. The case is unique since biphasic synovial sarcomas have yet to be reported to occur in the kidney and fine needle aspiration biopsy findings of this renal neoplasm have never been reported to our knowledge. CONCLUSION: Synovial sarcoma should be a diagnostic consideration particularly in a young adult with a malignant spindle cell neoplasm of the kidney. The list of differential diagnoses should include sarcomatoid renal cell carcinoma, sarcomatoid transitional cell carcinoma of the renal pelvis, angiomyolipoma and monophasic or biphasic synovial sarcoma.     

Hypothesis: A New Role for the Renin-Angiotensin System in Ureteric Bud Branching

Branching morphogenesis in the developing mammalian kidney involves growth and branching of the ureteric bud (UB), leading to formation of its daughter collecting ducts, calyces, pelvis and ureters. Even subtle defects in the efficiency and/or accuracy of this process have profound effects on the ultimate development of the kidney and result in congenital abnormalities of the kidney and urinary tract. This review summarizes current knowledge regarding a number of genes known to regulate UB development and emphasizes an emerging role for the renin-angiotensin system (RAS) in renal branching morphogenesis. Mutations in the genes encoding components of the RAS in mice cause renal papillary hypoplasia, hydronephrosis, and urinary concentrating defect. These findings imply that UB-derived epithelia are targets for angiotensin (ANG) II actions during metanephric kidney development. Here, it is proposed that papillary hypoplasia in RAS-deficient mice is secondary to an intrinsic defect in the development of the renal medulla. This hypothesis is based on the following observations: a) UB and surrounding stroma express angiotensinogen (AGT) and ANG II AT1 receptors in vivo; b) ANG II stimulates UB cell process extension, branching and cord formation in collagen gel cultures in vitro; and c) AT1 blockade inhibits ANG II-induced UB cell branching. It is further postulated that ANG II is a novel stroma-derived factor involved in stroma/UB cross-talk which regulates UB branching morphogenesis.