Double Ligation Research Articles

Open Appendectomy in Children: Double Ligation Versus Stump Inversion

Background: The aim of the study is to draw a comparison between two appendectomy techniques of open appendectomy procedure entitled double ligation and stump inversion. Methods: The study was designed retrospectively at two different points in time when one of these two techniques was performed in our department. At the first time period in 2008 (Group A) 166 double ligation appendectomies were performed in comparison to the latter in 2011 (GroupB) where 202 stump inversion have been carried out. The main outcome measures were postoperative complications and they were assessed according to the intention to- treat analysis principle. Results: There was no mortality and overall complication rate was similar in both groups. A total number 60 simple wound infections treated with wound dressing. The cases of deep wound infections and abdominal abscesses underwent antibiotic treatment and four children in group B required reoperation. The only statistically significant outcome is that the period of hospital stay of groupB turned out to be longer than groupA. Conclusion: Considering the main surgical principle of “the preference of the more simple technique”, we believe that; in performance of an open appendectomy, the preference of a double ligation technique would be more appropriate.

Development of a high fidelity pressurized porcine beating heart simulator for cardiac surgery training.

Development of a high-fidelity cardiac surgery simulator (CSS) requires integration of a heart model with a mock cardiopulmonary bypass (CPB) circuit that can provide feedback to mimic the pathophysiology of cardiac surgery. However, the cost of commercially available simulators precludes regular use. We describe steps in the construction of a high-fidelity CSS that integrates a pulsatile paracorporeal ventricular-assist device (Pulse-VAD) and a commercially available CPB simulator. Eight porcine hearts were initially prepared. The configuration consisted of cannulation of the distal descending aorta and the inferior vena cava to enable pressurization of the heart after connection to the Califia® simulator, as well as Pulse-VAD cannulation (fitted with inflatable balloons) of both ventricles. After each simulation run, the team addressed key issues to derive successive model changes through consensus. Key modifications included: a) pressure maintenance of the cardiac chambers (removal of lungs, Pulse-VAD cannulation sites at the left pulmonary artery and vein, double ligation of arch vessels); b) high-fidelity beating of both ventricles (full Pulse-VAD bladder filling and ensuring balloon neck placement at the valvular plane) and c) reproducible management of porcine anatomy (management of porcine aorta, ligation of left azygous vein and shortened ascending thoracic aortic segment). A CSS can be prepared at low cost, with integration into a high-fidelity CPB simulator with a novel beating heart component. This setup can be used in teaching the basics of CPB techniques and complex surgical procedures. Future work is needed to validate this model as a simulation instrument.

Aortopulmonary window: Morphology, diagnosis, and long-term results.

Aortopulmonary window (APW) is a rare congenital heart defect. We reviewed our experience with this condition over the last two decades. Between September 1993 and December 2013, 62 patients underwent surgery for APW. Depending on the associated lesions, they were divided into two groups: Simple (Group 1) or complex (Group 2). In the complex group, six patients had a ventricular septal defect, five patients had interrupted aortic arch, three patients had tetralogy of Fallot, two patients had double outlet right ventricle, and one patient had the right pulmonary artery arising from the ascending aorta. Mean age at repair was 21.6 ± 32.02 months (median = 6, range 0.1-144 months). By preoperative echocardiographic assessment 27 out of 62 patients had severe pulmonary artery hypertension (52% of the cohort). Patch repair of APW was performed using the sandwich method (transwindow) (n = 27; 43.5%), transaortic (n = 18; 29%), and transpulmonary artery (n = 5; 8.1%) approaches; 10 patients (16.1%) underwent double ligation and two (3.2%) underwent division and suturing. Overall hospital mortality in group 1 was 6.97% (3/43) and in group 2 it was 21% (4/19), p = 0.085. Mean hospital stay in group 1 was 6.9 ± 2.4 days (median = 7 days) and in group 2 was 12 ± 6.1 days (median = 13 days), p = 0.0001. Follow-up in group 1 was 1.6-9.8 years (median = 6 years); in group 2, it was 1.8-8.9 years (median = 6.5 years). There were no late deaths. Two patients needed reintervention for distortion of the right pulmonary artery origin. All patients were in New York Heart Association Class I/II at last follow up. There are multiple acceptable surgical strategies for the treatment of aortopulmonary window. Despite a relatively advanced age and substantial number of patients with severe pulmonary hypertension the outcomes can still be good. Associated anomalies complicate the repair. Patients in the complex group had a protracted hospital course and a higher early mortality but similar late survival.

Von Willebrand factor deficiency leads to impaired blood flow recovery after ischaemia in mice.

Neovascularisation, i. e. arteriogenesis and angiogenesis, is an inflammatory process. Therefore attraction and extravasation of leukocytes is essential for effective blood flow recovery after ischaemia. Previous studies have shown that von Willebrand factor (VWF) is a negative regulator of angiogenesis. However, it has also been shown that VWF facilitates leukocyte attraction and extravasation. We aimed to investigate the role of VWF in arteriogenesis and angiogenesis during post-ischaemic neovascularisation. Wild-type (WT) and VWF deficient (VWF-/-) C57BL/6 mice were subjected to hindlimb ischaemia via double ligation of the left femoral artery, and blood flow recovery was followed over time, using Laser Doppler Perfusion Imaging. Blood flow recovery was impaired in VWF-/- mice. After 10 days, VWF-/- mice showed a 43 ± 5 % recovery versus 68 ± 5 % in WT. Immunohistochemistry revealed that both arteriogenesis in the adductor muscles and angiogenesis in the gastrocnemius muscles were reduced in VWF-/- mice. Furthermore, leukocyte infiltration in the affected adductor muscles was reduced in VWF-/- mice. Residual paw perfusion directly after artery ligation was also reduced in VWF-/- mice, indicating a decrease in pre-existing collateral arteriole density. When we quantified collateral arterioles, we observed a 31 % decrease in the average number of collateral arterioles in the pia mater compared to WT mice (57 ± 3 in WT vs 40 ± 4 pial collaterals in VWF-/-). We conclude that VWF facilitates blood flow recovery in mice. VWF deficiency hampers both arteriogenesis and angiogenesis in a hindlimb ischaemia model. This is associated with impaired leukocytes recruitment and decreased pre-existing collateral density in the absence of VWF.

Neither Isolated Hepatic Arterial Clamping nor Hepatic Arterial Ligation Induce Ischemic Type Biliary Lesions in Rats.

BACKGROUND Ischemic type biliary lesions (ITBL) is a troublesome complication after liver transplantation. Little is known about its pathogenesis and there is particularly little data about morphological alterations. Prolonged warm and cold ischemia time and reduced hepatic arterial perfusion are risk factors leading to ITBL. There are only a few animal models described in literature. Therefore, we examined the effects of 3 h of hepatic artery ischemia-reperfusion (3 h I/R) and hepatic arterial ligation (HAL), both combined with ligation of the peribiliary plexus (PBP). MATERIAL AND METHODS 3 h I/R was performed by clamping the hepatic artery with microvascular clamps for 3 h. HAL was performed by ligation of the hepatic artery. Both procedures were combined with stenting of the common bile duct with double ligation of the PBP. A sham group without clamping served as control. Serum activities of aspartate transaminase (AST) and alanine transaminase (ALT), direct and total bilirubin (DB/TB), and lactate dehydrogenase (LDH) were measured. Bile flow was analyzed and histological examinations of leukocyte infiltration (CAE), cell proliferation (PCNA), apoptotic cells (HE), and bile ducts morphology (CK7) were performed. Western blots of the vascular endothelial growth factor (VEGF) and caspase 3 were made to investigate vascular growth expression and apoptotic cell death. RESULTS 3 h I/R and HAL were associated with a significant hepatocellular injury and inflammation, shown through increased AST and ALT, leukocyte infiltration, and apoptotic cell death. An increase of bile ducts and a reduction of arteries/bile duct ratio after 30 days was observed in the 3 h I/R group and HAL, but no ITBL-typical bile duct necrosis, intrahepatic strictures, or dilatations of bile ducts occurred. CONCLUSIONS Morphological alterations in a rat animal model of 3 h I/R and HAL could be demonstrated. However, a model of intrahepatic biliary lesions could not be established through hepatic arterial ligation or through 3-h hepatic arterial ischemia and reperfusion.

Histone H2B-IFI16 Recognition of Nuclear Herpesviral Genome Induces Cytoplasmic Interferon-β Responses.

IFI16 (gamma-interferon-inducible protein 16), a predominantly nuclear protein involved in transcriptional regulation, also functions as an innate immune response DNA sensor and induces the IL-1β and antiviral type-1 interferon-β (IFN-β) cytokines. We have shown that IFI16, in association with BRCA1, functions as a sequence independent nuclear sensor of episomal dsDNA genomes of KSHV, EBV and HSV-1. Recognition of these herpesvirus genomes resulted in IFI16 acetylation, BRCA1-IFI16-ASC-procaspase-1 inflammasome formation, cytoplasmic translocation, and IL-1β generation. Acetylated IFI16 also interacted with cytoplasmic STING and induced IFN-β. However, the identity of IFI16 associated nuclear proteins involved in STING activation and the mechanism is not known. Mass spectrometry of proteins precipitated by anti-IFI16 antibodies from uninfected endothelial cell nuclear lysate revealed that histone H2B interacts with IFI16. Single and double proximity ligation microscopy, immunoprecipitation, EdU-genome labeled virus infection, and chromatin immunoprecipitation studies demonstrated that H2B is associated with IFI16 and BRCA1 in the nucleus in physiological conditions. De novo KSHV and HSV-1 infection as well as latent KSHV and EBV infection induces the cytoplasmic distribution of H2B-IFI16, H2B-BRCA1 and IFI16-ASC complexes. Vaccinia virus (dsDNA) cytoplasmic replication didn’t induce the redistribution of nuclear H2B-IFI16 or H2B into the cytoplasm. H2B is critical in KSHV and HSV-1 genome recognition by IFI16 during de novo infection. Viral genome sensing by IFI16-H2B-BRCA1 leads to BRCA1 dependent recruitment of p300, and acetylation of H2B and IFI16. BRCA1 knockdown or inhibition of p300 abrogated the acetylation of H2B-IFI16 or H2B. Ran-GTP protein mediated the translocation of acetylated H2B and IFI16 to the cytoplasm along with BRCA1 that is independent of IFI16-ASC inflammasome. ASC knockdown didn’t affect the acetylation of H2B, its cytoplasmic transportation, and the association of STING with IFI16 and H2B during KSHV infection. Absence of H2B didn’t affect IFI16-ASC association and cytoplasmic distribution and thus demonstrating that IFI16-H2B complex is independent of IFI16-ASC-procaspase-1-inflammasome complex formed during infection. The H2B-IFI16-BRCA1 complex interacted with cGAS and STING in the cytoplasm leading to TBK1 and IRF3 phosphorylation, nuclear translocation of pIRF3 and IFN-β production. Silencing of H2B, cGAS and STING inhibited IFN-β induction but not IL-1β secretion, and cGAMP activity is significantly reduced by H2B and IFI16 knockdown during infection. Silencing of ASC inhibited IL-1β secretion but not IFN-β secretion during de novo KSHV and HSV-1 infection. These studies identify H2B as an innate nuclear sensor mediating a novel extra chromosomal function, and reveal that two IFI16 complexes mediate KSHV and HSV-1 genome recognition responses, with recognition by the IFI16-BRCA1-H2B complex resulting in IFN-β responses and recognition by IFI16-BRCA1 resulting in inflammasome responses.

Effect of dexmedetomidine on liver injury in rats with obstructive jaundice

Objective To evaluate the effect of dexmedetomidine on liver injury in the rats with obstructive jaundice. Methods Forty-five healthy male Sprague Dawley rats, weighing 250-300 g, aged 8-9 weeks, were divided into 3 groups (n=15 each) using a random number table: sham operation group (S group), obstructive jaundice group (OJ group) and dexmedetomidine group (D group). Obstructive jaundice was induced in rats by division and double ligation of the common bile duct in OJ and D groups.Dexmedetomidine 100 μg/kg was injected intraperitoneally at 72 h after establishment of the model in group D. At 3, 5 and 24 h after administration, blood samples were collected from hearts for determination of the plasma alanine aminotransferase (ALT) and C-reactive protein (CRP) levels.After blood sampling at each time point, the specimens from the external right lobe of the liver were obtained for detection of the expression of Toll-like receptor 4 (TLR4) mRNA (by real-time polymerase chain reaction) and TLR4 content (by enzyme-linked immunosorbent assay) in liver tissues and for pathological examination of liver tissues (with light microscope). Results Compared with group S, the plasma ALT and CRP levels were significantly increased at each time point after administration, and the expression of TLR4 mRNA in liver tissues was significantly up-regulated, and TLR4 content in liver tissues was significantly increased in OJ and D groups (P<0.05). Compared with group OJ, the plasma ALT and CRP levels were significantly decreased at each time point after administration, and the expression of TLR4 mRNA in liver tissues was significantly down-regulated, and TLR4 content in liver tissues was significantly decreased in group D (P<0.05). The degree of damage to liver tissues was significantly attenuated in group D compared with group OJ, and was aggravated in group D compared with group S. Conclusion Dexmedetomidine can reduce liver injury in the rats with obstructive jaundice. Key words: Dexmedetomidine; Jaundice, obstructive; Liver diseases

Repair of an Endoscopic Retrograde Cholangiopancreatography-Related Large Duodenal Perforation Using Double Endoscopic Band Ligation and Endoclipping

Endoscopic closure techniques have been introduced for the repair of duodenal wall perforations that occur during endoscopic retrograde cholangiopancreatography (ERCP). We report a case of successful repair of a large duodenal wall perforation by using double endoscopic band ligation (EBL) and an endoclip. Lateral duodenal wall perforation occurred during ERCP in a 93-year-old woman with acute calculous cholangitis. We switched to a forward endoscope that had a transparent band apparatus. A 2.0-cm oval-shaped perforation was found at the lateral duodenal wall. We repaired the perforation by sequentially performing double EBL and endoclipping. The first EBL was performed at the proximal edge of the perforation orifice, and two-thirds of the perforation were repaired. The second EBL, which also included the contents covered under the first EBL, repaired the defect almost completely. Finally, to account for the possible presence of a residual perforation, an endoclip was applied at the distal end of the perforation. The detection and closure of the perforation were completed within 10 minutes. We suggest that double EBL is an effective method for closure.

Rational design of novel N-alkyl-N capped biostable RNA nanostructures for efficient long-term inhibition of gene expression.

Computational techniques have been used to design a novel class of RNA architecture with expected improved resistance to nuclease degradation, while showing interference RNA activity. The in silico designed structure consists of a 24–29 bp duplex RNA region linked on both ends by N-alkyl-N dimeric nucleotides (BCn dimers; n = number of carbon atoms of the alkyl chain). A series of N-alkyl-N capped dumbbell-shaped structures were efficiently synthesized by double ligation of BCn-loop hairpins. The resulting BCn-loop dumbbells displayed experimentally higher biostability than their 3′-N-alkyl-N linear version, and were active against a range of mRNA targets. We studied first the effect of the alkyl chain and stem lengths on RNAi activity in a screen involving two series of dumbbell analogues targeting Renilla and Firefly luciferase genes. The best dumbbell design (containing BC6 loops and 29 bp) was successfully used to silence GRB7 expression in HER2+ breast cancer cells for longer periods of time than natural siRNAs and known biostable dumbbells. This BC6-loop dumbbell-shaped structure displayed greater anti-proliferative activity than natural siRNAs.

Variability in Endogenous Perfusion Recovery of Immunocompromised Mouse Models of Limb Ischemia.

Immunocompromised hind limb ischemia (HLI) murine models are essential for preclinical evaluation of human cell-based therapy or biomaterial-based interventions. These models are used to generate proof of principle that the approach is effective and also regulatory preclinical data required for translation to the clinic. However, surgical variations in creation of HLI models reported in the literature introduce variability in the pathological manifestation of the model, in consequence affecting therapeutic endpoints. This study aims to compare the extent of vascular regeneration in HLI-induced immunocompromised murine models to obtain a stable and more reproducible injury model for testing. Athymic and Balb/C nude mice underwent HLI surgery with single and double ligation of femoral artery (FA). The recovery from surgery was observed over a period of 2 weeks with respect to ischemia reperfusion using laser Doppler and clinical signs of necrosis and ambulatory impairment. Double ligation of the FA results in a more severe response to ischemia in Balb/C with endogenous perfusion recovery up to 50% ± 10% compared with 75% ± 20% in athymic nude mice. Single iliac artery (IA) and FA lead to creation of mild ischemia compared with femoral artery-vein (FAV) pair ligation in Balb/C. Microcirculatory parameters indicate significantly lower capillary numbers (26 ± 3/mm(2)) and functional capillary density (203 ± 5 cm/cm(2)) in the FAV group. In this study, we demonstrate a reproducible, arterial double ligation in an immunocompromised Balb/C nude mouse model that exhibits characteristic pathological signs of ischemia with impaired endogenous recovery.

Principles and applications of Ligation Mediated PCR methods for DNA-based typing of microbial organisms.

A significant number of DNA-based techniques has been introduced into the field of microorganisms' characterization and taxonomy. These genomic fingerprinting methods were developed to detect DNA sequence polymorphisms by using general principles, such as restriction endonuclease analysis, molecular hybridization, and PCR amplification. In recent years, some alternative techniques based on ligation of oligonucleotide adapters before DNA amplification by PCR, known as Ligation-Mediated PCR methods (LM PCR), have been successfully applied for the typing of microorganisms below the species level. These molecular methods include: Amplified Fragment Length Polymorphism (AFLP), Amplification of DNA fragments Surrounding Rare Restriction Sites (ADSRRS), PCR Melting Profiles (PCR MP), Ligation Mediated PCR/Shifter (LM PCR/Shifter), Infrequent-Restriction-Site Amplification (IRS PCR), double digestion Ligation Mediated Suppression PCR (ddLMS PCR). These techniques are now applied more and more often because they involve less time, are comparably inexpensive, and require only standard lab equipment. Here, we present a general review of this group of methods showing their possibilities and limitations. We also identify questions and propose solutions which may be helpful in choosing a particular LM PCR method for the achievement of the required goal.

FOXE1 polymorphisms and non-syndromic orofacial cleft susceptibility in a Chinese Han population.

FOXE1 plays an important role in craniofacial development. The aim of this study was to investigate associations between genetic variants of FOXE1 and risk of non-syndromic orofacial clefts in a Chinese population. Three potentially functional SNPs of FOXE1 (rs3758250 and rs907577 in the 5' upstream and rs7043516 in the 3'-UTR) were selected and their associations with non-syndromic orofacial cleft susceptibility were investigated in a case-control study from a Chinese population (602 cases and 605 controls). Genotyping was performed with double ligation and multiplex fluorescence PCR. Associations between the SNPs and risk of non-syndromic orofacial clefts and its subgroups were estimated from unconditional logistic regression analysis. Luciferase reporter assay was conducted to assess SNP function. Overall, we did not find any of the individual SNP or haplotype was associated with NSOC susceptibility. Nevertheless, in stratified analysis, we found rs7043516, locating in the 3'-UTR of FOXE1, was associated with risk of cleft lip only. Further invitro luciferase assay indicated that this SNP could contribute to differential binding ability with miRNA. Taken together, this study showed that rs7043516 may be considered as a potentially susceptible marker of cleft lip only among Chinese Han populations.

Prokaryotic Expression of the Oligopeptide Transporter hPepT2(560-663)

Peptide transporter 2 is a high affinity and low capacity transporter, that has recently been found in the mammalian kidney, brain, lung, and mammary glands, which is known to transport dipeptides and tripeptides and to reabsorb small peptides generated by luminal peptidases in the kidney. In addition, peptide transporter 2 can transport peptide-like drugs and play important roles in the transshipment and positioning of drugs. In this paper, an E.coli BL21(DE3) containing pET30a(+)-hPepT2(560-663) recombinant plasmid was obtained by using PCR, double restriction enzyme digestion, ligation, and transformation. Then, the effect of changing both the induction time and induction dose using Isopropyl β-D-1-Thiogalactopyranoside (IPTG) on the bacterial expression of hPepT2(560-663) was detected by SDS-PAGE electrophoresis, the optimum expression conditions (at 37°) were identified as: 3 h and a working concentration of 0.5 mM Isopropyl β-D-1-Thiogalactopyranoside. Finally, we purified the target protein hPepT2(560-663) via Sephadex G-75 gel chromatography. These results will facilitate in future studies on the nature and function of the protein.

Evaluation of Complications between Double Puncture Laparoscopic Sterilization and Conventional Tubal Ligation Methods

Evaluation of Complications between Double Puncture Laparoscopic Sterilization and Conventional Tubal Ligation Methods

Synthesis of misfolded glycoprotein dimers through native chemical ligation of a dimeric peptide thioester.

Glycoprotein quality control processes are very important for an efficient production of glycoproteins and for avoiding the accumulation of unwanted toxic species in cells. These complex processes consist of multiple enzymes and chaperones such as UGGT, calnexin/calreticulin, and glucosidase II. We designed and synthesized monomeric and dimeric misfolded glycoprotein probes. Synthetic homogeneous monomeric glycoproteins proved to be useful substrates for kinetic analyses of the folding sensor enzyme UGGT. For a concise synthesis of a bismaleimide-linked dimer, we examined double native chemical ligation (dNCL) of a dimeric peptide-α-thioester. The dNCL to two equivalents of glycopeptides gave a homodimer. The dNCL to a 1 : 1 mixture of a glycopeptide and a non-glycosylated peptide gave all the three possible ligation products consisting of two homodimers and a heterodimer. Both the homodimer bearing two Man9GlcNAc2 (M9) oligosaccharides and the heterodimer bearing one M9 oligosaccharide were found to be good substrates of UGGT.

Combined interventional and surgical treatment for a rare case of double patent ductus arteriosus.

The present study describes the case of a 2.5-year-old girl with double patent ductus arteriosus (PDA) that was successfully treated following interventional and surgical treatment. Bilateral ductus arteriosus is a very rare condition, which is assumed to occur when the branchial-type arterial system transforms into the mammalian-type arterial system during the development of the aorta and its branches. This case was misdiagnosed as ordinary PDA by echocardiography prior to the first surgery and the surgery was not successful because of poor accessibility. Enhanced computed tomography subsequently showed situs solitus, atrial situs, levocardia, right-sided aortic arch with right-sided descending aorta, an isolated left subclavian artery and double PDA. Interventional treatment was performed and intraoperative aortic arch angiography showed that the descending aorta was the origin of the first funnel-type PDA (PDA-1). The left subclavian artery was not connected to the aorta but was connected to the pulmonary artery with a very narrow winding duct, which was PDA-2. Interventional treatment via PDA-2 also failed because passing a guidewire through the twisted PDA-2 was difficult. The child was immediately transferred to the surgical operation room for double PDA ligation and left subclavian artery reconstruction under median thoracotomy. The surgical procedure succeeded and the patient recovered quickly. The failure of the interventional treatment may be attributed to the difficulty in establishing a path. The soft tip of the hardened guidewire was relatively long. If the hardened part of the wire was sent to the appropriate place to support the pathway, the soft tip would be forced to enter the vertebrobasilar artery system. A similar problem was encountered when the left subclavian artery was selected for intervention. Shortening the length of the soft tip of the hardened guidewire may have enabled smooth completion of the establishment of the pathway. However, this type of hardened guidewire requires specific production.

Single-port laparoscopic percutaneous double ligation for pediatric inguinal hernias: report of a new technique and early results.

Several single-port laparoscopic hernial repair methods have been designed to treat inguinal hernia in children, but reliable and safe ligation of the hernial sac should be further investigated. This study aimed to investigate a new technique for laparoscopic percutaneous double ligation for pediatric inguinal hernias with a set of home-made instruments. Before each operation, a set of home-made instruments were prepared, including a curved puncture needle, a lasso suture, a dual ligation suture, and occasionally, a flat-headed puncture needle for obese patients. After a series of operational steps, the hernial sac was doubly extracorporeally ligated, leaving only one puncture point in the inguinal region and one incision in the navel. Between October 2011 and September 2013, 236 children (211 boys and 25 girls) underwent hernial repair using this novel technique. In 38.8% (85/219) of patients with the preoperative diagnosis of unilateral inguinal hernia, contralateral patent processus vaginalis was confirmed during the laparoscopic surgery and subsequent repair was performed. In 134 cases of unilateral repair, the mean operative time was 11min (range 5-16min), and it was 19min (range 13-29min) in 102 cases of bilateral repair. No recurrence or complications have been observed to date. This study shows a unique technique of percutaneous double ligation of the hernial sac using a minimally invasive technique with the aid of a transabdominal 5-mm telescope and a set of home-made instruments. Single-port laparoscopic hernial repair using this technique is feasible and appears to be safe.

Morphometric study of the testis and reproductive tract (including sperm granuloma) after vasectomy in mature rats

By utilizing the rabbit model, previous studies have found good evidence indicating that vasectomy-induced spermatogenic damage is pressure-mediated: the damage occurs when the occluded reproductive tract is unable to accommodate additional spermatozoa produced by the testis. More studies with the more commonly used rat model have shown, however, controversial results on whether and why the damage occurs. In this study, 12 mature male Sprague-Dawley rats were subjected to unilateral vasectomy: double ligation (without severing) of the vas deferens exposed via a small inguinal incision; 37 days after the operation, the testes, epididymides, vasa deferentia (juxta-epididymal segments), and sperm granulomas (at the vasectomy site) were removed to obtain methacrylate resin-embedded sections and morphometric studies carried out with light microscopy. Marked spermatogenic damage with spermatids and spermatocytes depleted in the seminiferous epithelium in 43% of the seminiferous tubule profiles was demonstrated in 5 of the 12 testes on the vasectomized side, and the damage was associated with smaller or absent sperm granulomas; in the other 7 testes with essentially normal spermatogenesis, there was an increase (by 111% on average) in the volume of the tubule lumen, associated with larger granulomas or granulomas containing more spermatozoa. There was an overall increase (by 66%) in the thickness of the rete testis in the 12 testes; the epididymis or vas deferens showed no distension. It seems therefore that the spermatogenic damage induced by vasectomy in rats is pressure-mediated as well, and that variation in the damage depends mainly on the postoperative development of the sperm granuloma.

Pedicle ties provide a rapid and safe method for feline ovariohysterectomy.

The specific objectives of the present study were to evaluate the rate of hemorrhage-related complications across a large number of feline pedicle tie (PT) procedures, and evaluate for a difference in surgical time between traditional pedicle double ligation (PDL) and PT procedures. In the initial phase of the study, 2136 intact female cats underwent an ovariohysterectomy using the PT technique. Hemorrhagic complications not detected intraoperatively were to be confirmed via exploratory surgery or necropsy. The second phase of the study recorded the duration of surgery for four groups: kittens undergoing PTs (n = 50), kittens undergoing PDL (n = 49), adult cats undergoing PTs (n = 50) and adult cats undergoing PDL (n = 54). Kittens were defined as a cat 4 months old or younger. Statistical comparisons of age, body weight and surgical times between the PT and PDL groups were performed within, but not between, kitten and adult cat categories. Six of 2136 (0.281%) cats experienced a hemorrhage-related complication associated with the ovarian pedicle. Five of the six ovarian pedicle hemorrhage-related complications were recognized and corrected intraoperatively, with the remaining hemorrhagic event being detected postoperatively. Surgical times were significantly shorter in PT kittens compared with PDL kittens (4.7 ± 0.1 mins vs 6.7 ± 0.1 mins) and PT adult cats compared with PDL adult cats (5.0 ± 0.2 mins vs 7.0 ± 0.2 mins). This study demonstrates that the PT technique is associated with a very low risk of hemorrhage-related complications and is significantly faster than double ligating the ovarian pedicle in kittens and adult cats. Use of the PT technique has the potential to be of significant economic benefit in institutions performing large numbers of feline ovariohysterectomies.

Expression of renal Oat5 and NaDC1 transporters in rats with acute biliary obstruction.

To examine renal expression of organic anion transporter 5 (Oat5) and sodium-dicarboxylate cotransporter 1 (NaDC1), and excretion of citrate in rats with acute extrahepatic cholestasis. Obstructive jaundice was induced in rats by double ligation and division of the common bile duct (BDL group). Controls underwent sham operation that consisted of exposure, but not ligation, of the common bile duct (Sham group). Studies were performed 21 h after surgery. During this period, animals were maintained in metabolic cages in order to collect urine. The urinary volume was determined by gravimetry. The day of the experiment, blood samples were withdrawn and used to measure total and direct bilirubin as indicative parameters of hepatic function. Serum and urine samples were used for biochemical determinations. Immunoblotting for Oat5 and NaDC1 were performed in renal homogenates and brush border membranes from Sham and BDL rats. Immunohistochemistry studies were performed in kidneys from both experimental groups. Total RNA was extracted from rat renal tissue in order to perform reverse transcription polymerase chain reaction. Another set of experimental animals were used to evaluate medullar renal blood flow (mRBF) using fluorescent microspheres. Total and direct bilirubin levels were significantly higher in BDL animals, attesting to the adequacy of biliary obstruction. An important increase in mRBF was determined in BDL group (Sham: 0.53 ± 0.12 mL/min per 100 g body weight vs BDL: 1.58 ± 0.24 mL/min per 100 g body weight, P < 0.05). An increase in the urinary volume was observed in BDL animals. An important decrease in urinary levels of citrate was seen in BDL group. Besides, a decrease in urinary citrate excretion (Sham: 0.53 ± 0.11 g/g creatinine vs BDL: 0.07 ± 0.02 g/g creatinine, P < 0.05) and an increase in urinary excretion of H(+) (Sham: 0.082 ± 0.03 μmol/g creatinine vs BDL: 0.21 ± 0.04 μmol/g creatinine, P < 0.05) were observed in BDL animals. We found upregulations of both proteins Oat5 and NaDC1 in brush border membranes where they are functional. Immunohistochemistry technique corroborated these results for both proteins. No modifications were observed in Oat5 mRNA and in NaDC1 mRNA levels in kidney from BDL group as compared with Sham ones. Citrate excretion is decreased in BDL rats, at least in part, because of the higher NaDC1 expression. Using the outward gradient of citrate generated by NaDC1, Oat5 can reabsorb/eliminate different organic anions of pathophysiological importance.