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Summary For microcirculation research there is a need for baseline data and feasibility protocols describing microcirculation of various organs. The aim of our study was to examine the reliability and reproducibility of sidestream dark-field (SDF) imaging within the renal cortical microcirculation in rats. Renal microcirculation was observed using SDF probe placed on the exposed renal surface via the upper midline laparotomy. Video sequences recorded intermittently in short apneic pauses were analyzed off-line by using AVA 3.0 software (MicroVision Medical, Amsterdam, the Netherlands). Results are expressed as mean (SD) or median (25–75% percentiles). We obtained 60 clear sequences from all recorded analyzable videos from all the animals. The total small vessel and all vessel density (in mm.mm–2) were (28.79 ± 0.40) and (28.95 ± 0.40), respectively. The perfused small and all vessel density were (28.79 ± 0.40) and (28.95 ± 0.40), respectively. The DeBacker Score was (19.14 ± 0.43), the proportion of perfused vessels was 100% (100–100%) and the microvascular flow index was 3.49 (3–3.75). We conclude SDF imaging provides a reliable method to examine the renal microvascular bed in vivo and thus can be used for the study of the renal cortical vascular network in various experimental diseases models and clinical settings. Lay Description This article aims to discuss the practicability of obtaining the baseline data and feasibility protocols needed to describe the microcirculation in various organs. In order to examine the reproducibility as well as the reliability of obtaining valid microcirculatory data of particular organs, the authors choose a renal cortical microcirculation in rats observed by using the sidestream dark field imaging (SDF). SDF method can be used non-invasively as well, especially in the sublingual area even in clinical research. However, in this study, the SDF probe is placed on the exposed renal surface. The subsequent analysis of all recorded videos is off-line using special software capable of image stabilization and semi-automatic evaluation of microcirculation. The program provides a number of output data, such as vascular density, vascular perfusion and blood velocity. The findings indicate that SDF imaging provides a reliable method of examining the renal microvascular bed in vivo and thus can be used to study the renal cortical vascular network in various experimental models of diseases and clinical settings.

This study gives a three-dimensional (3D) structural analysis of rat nephrons and their connections to collecting ducts. Approximately 4,500 2.5-μm-thick serial sections from the renal surface to the papillary tip were obtained from each of 3 kidneys of Wistar rats. Digital images were recorded and aligned into three image stacks and traced from image to image. Short-loop nephrons (SLNs), long-loop nephrons (LLNs), and collecting ducts (CDs) were reconstructed in 3D. We identified a well-defined boundary between the outer stripe and the inner stripe of the outer medulla corresponding to the transition of descending thick limbs to descending thin limbs and between the inner stripe and the inner medulla, i.e., the transition of ascending thin limbs into ascending thick limbs of LLNs. In all nephrons, a mosaic pattern of proximal tubule (PT) cells and descending thin limb (DTL) cells was observed at the transition between the PT and the DTL. The course of the LLNs revealed tortuous proximal “straight” tubules and winding of the DTLs within the outer half of the inner stripe. The localization of loop bends of SLNs in the inner stripe of the outer medulla and the bends of LLNs in the inner medulla reflected the localization of their glomeruli; i.e., the deeper the glomerulus, the deeper the bend. Each CD drained approximately three to six nephrons with a different pattern than previously established in mice. This information will provide a basis for evaluation of structural changes within nephrons as a result of physiological or pharmaceutical intervention.

Upper abdominal ultrasound imaging in a 63-year-old woman who had been hypertensive for ten years revealed a tumour at the lower pole of the left kidney. It protruded from the renal surface and gave dense echoes, suggestive more of an angiomyolipoma than a hypernephroma. The former diagnosis was reenforced by the angiographic appearance and confirmed by biopsy at the time of surgery. Nephrectomy was performed and the postoperative course was without complication.

Made available in DSpace on 2014-10-01T13:08:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-04-01Bitstream added on 2014-10-01T14:03:47Z : No. of bitstreams: 1 S0102-09352014000200018.pdf: 1144645 bytes, checksum: b59c5c5849cc50e5f42e1f1a03788805 (MD5) O objetivo deste estudo foi avaliar, por meio da ultrassonografia convencional modo B, as características sonográficas e a biometria dos rins de fetos caninos, bem como determinar os índices vasculares da artéria renal dos conceptos ao Doppler Triplex. Foram utilizadas 24 fêmeas Shi-tzu e Pugs pesando de quatro a 10 kg e com idade entre quatro e seis anos. Ao modo B, a ecobiometria renal fetal, a regularidade da superfície renal, a ecotextura e a relação córtico-medular foram avaliadas durante a quinta, sexta, sétima e oitava semanas gestacionais. Ao Doppler Triplex, durante o mesmo período em que se realizou o exame convencional, foram determinados o pico de velocidade sistólica (PVS), a velocidade diastólica final (EDV) e o índice de resistência vascular (RI) e de pulsatividade (PI). Ao modo B, não foram detectadas alterações em rins fetais, e à ecobiometria renal dos fetos, foi possível determinar medidas renais importantes, verificando-se aumento das biometrias no decorrer do desenvolvimento fetal (P0,05). Concluiu-se que o modo B e o Doppler Triplex são ferramentas importantes para a avaliação do desenvolvimento renal fetal, com a utilização da ecobiometria renal e avaliação dos indices vasculares da artéria renal de fetos caninos. The aim of this study was to assess the sogographic parameters and biometry of canine fetal kidneys using the B mode, and to determinate the vascular index of the fetal renal arteries using the Doppler Triplex. Twenty four Shi-tzu and Pug, weighting between 4 and 10kg, aging between 4 and 6 years old were evaluated. The B mode, the fetal renal echobiometry and regularity of the renal surface, echotexture and cortex:medular ratio were evaluated during the 5th, 6th, 7th and 8th weeks of pregnancy. At the same time point of the B mode evaluation, the Doppler Triplex was carried out to assess the sistolic peak velocity (SPV), end diastolic velocity (EDV), vascular resistive (RI) and pulsatility index (PI). B mode revealed no fetal renal abnormalities and echobiometry showed important measurements during fetal development (P0.05). B mode and Doppler Triplex were important tools for the assessment of fetal renal development, using echobiometry and renal arterial index in canie fetuses. Unesp Faculdade de Ciências Agrárias e Veterinárias Unesp Faculdade de Ciências Agrárias e Veterinárias

In patients with autosomal dominant polycystic kidney disease (ADPKD), laparoscopic cyst decortication (LCD) has been proposed as a means to relieve chronic cyst-related pain. We present our 7-year experience with LCD for ADPKD with regard to pain relief, hypertension, and renal function.Between August 1994 and February 2001, 29 ADPKD patients with chronic pain (N=29), hypertension (N=21), and renal insufficiency (N=10) underwent 35 LCD procedures. Every detectable cyst within 2 mm of the renal surface was treated. Pain relief was assessed using a pain analog scale; relative pain relief (RPR) equaled (preoperative pain score) - (postoperative pain score)/(preoperative pain score). Hypertension was evaluated using the antihypertensive therapeutic index (ATI): [(dose of blood pressure medication 1/max dose 1) + (dose med 2/max dose 2) + etc.] x 10. Renal function was assessed using the Cockcroft and Gault formula for creatinine clearance.The mean operating room time was 4.9 hours (range 2.6-6.6 hours) with no conversions to open surgery. An average of 220 cysts (range 4-692) were treated per patient. The mean follow-up was 32.3 months (range 6-72 months). The RPR was 58%, 47%, and 63% at 12, 24, and 36 months, respectively. At 12, 24, and 36 months, 73%, 52%, and 81% of patients, respectively, noted50% improvement in their pain compared with the preoperative situation. Five patients became normotensive, and patients improved their ATI by an average of 49% (range 11%-93%). However, six patients had worsening hypertension, with an ATI increase averaging 53% (range 11%-122%), and one patient who was not hypertensive preoperatively has since developed hypertension. The creatinine clearance changed +4%, +7%, and -2% at 12, 24, and 36 months, respectively. Only one patient had a20% increase in creatinine clearance. The only patients with a20% decrease in creatinine clearance were those who had a creatinine clearance30 mg/dL preoperatively (average decrease 34% [range 20%-51%]).For ADPKD patients with debilitating pain, extensive LCD can provide durable relief. In the majority of patients with pain and hypertension, a marked improvement in blood pressure also occurs. Cyst decortication was not associated with worsening renal function; indeed, renal function remained largely unchanged over the 3-year follow-up period.

The glomerular distribution in the renal cortex of the Munich Wistar Frömter (MWF) rat, a substrain of the Munich Wistar rat selected for superficial glomeruli, was compared to that of a control strain (LEW/Ztm) between 10 and 150 days of age. While there were no significant differences in body growth, kidney weight, or growth of the renal cortex in these two strains, the average diameter of Bowman’s capsule and of the glomerular tuft was significantly larger (about 12%) in rats of the MWF strain which were older than 60 days. In histological sections of kidneys of MWF rats in all age groups, many glomeruli in direct contact with the renal capsule were found; thus, this developmental step must have taken place before 10 days of age. The appearance of superficial glomeruli was due to a shift of glomeruli to a position just under the renal surface, the subcapsular zone or ‘cortex corticis’, which is normally free of glomeruli. For the rest of the renal cortex there were only slight differences in glomerular density and in total number of glomeruli per section between these two strains. These results lead us to suppose that superficial glomeruli belong to a special nephron type; thus, these glomeruli are not enveloped by parts of the proximal tubule.

The perinephric space is not a simple fat-filled chamber through which fluid may be distributed unhindered. It is divided into multiple compartments by fibrous lamellae, the bridging septa. Some of these structures arise from the renal capsule and extend to the perinephric fascia; others are attached only to the renal capsule and are arranged more or less parallel to the renal surface. Still others connect the anterior to the posterior leaves of the perinephric fascia. The resulting compartments exert an important influence on pathologic processes, resulting, for example, in limitation of the spread of pus and tamponade of bleeding points. The configuration of many perinephric collections can only be understood by knowledge of the existence and arrangement of these lamellae. The current criteria for differentiation of subcapsular from perinephric hematomas are shown to be in error, and a new sign for such differentiation is described. There are also implications regarding therapeutic drainage of perinephric abscesses, particularly by the percutaneous route. A new classification of the perinephric fascia is proposed.

Summary— The use of the Doppler probe to localise the intrarenal vessels was assessed in 15 dogs. This prevented the need for renal artery clamping and radial nephrotomies were placed in silent areas on the renal surface. Functional studies were performed post-operatively at 48 h and 1 month, using creatinine clearance, microfil casts and cast angiography. There was no significant loss of function when three or six radial nephrotomies were made and the Doppler accurately localised sites for nephrotomy between the intrarenal arteries and veins which were undamaged.

The passage time of I131-Hippuran and I131-Inulin was measured with Anger camera-scintigraphy after rapid arterial injection of these substances and compared with the results obtained with the Lissamingreen method. Corresponding to the passage time of Lissamingreen through the loops of Henle, there was a decrease in the kidney size in the scintiphotogram. in further agreement with the intravital microscopy, the passage time of the radioactivity was prolonged during hypotension and high intra-pelvic pressure. Similar results were obtained with collimator measurements of I125-Inulin and I125-Hippuran on the renal surface and with simultaneous measurements of the passage time of Lissamingreen.

Volumes and surface areas of 45 kidneys were determined ultrasonographically in vivo before autopsy and in a water bath phantom after autopsy by means of both the ellipsoid and the stepped section methods. Comparison of results revealed that renal volume may be determined by the simplest method, the ellipsoid method, with sufficient accuracy for clinical use. Results also revealed that renal mass expressed in grams may be directly obtained from renal volume expressed in milliliters, but mass in grams was found to correlate better with renal surface area than with renal volume. A formula relating renal mass to both volume and surface area was developed from regression analysis of the data and was found to provide a more precise estimate of renal mass than does mass computed from either volume or surface area alone.

The microperfusion pump described in this paper allows to perfuse the same peritubular capillary area on the renal surface with different test solutions. Solutions can be changed by means of a microcannula inside the pump which for this purpose can be moved near to the tip of the pipette. Concentration effect relations of various agents may thus be obtained on the single nephron level in vivo. This is illustrated on the example of the inhibitory effect of acetazolamide on proximal tubular reabsorption. Inhibition of this tubular function has been assessed by means of repeated determinations of split droplet half times.