A causal analysis of intra-abdominal hemorrhage after reduced-size liver transplantation in rat

In this study, we analyzed causes of abdominal hemorrhage after reduced-size liver transplantation in rat. Healthy SD rats (weight range of 260–280 g) underwent liver transplantation, the donors were female and the recipients were male rats. The recipients were, on average, by <10 g heavier than the donors. All operations on donor rats were performed by the same person using unaided eyesight. Operations on recipient rats were performed by two persons using unaided eyesight. About 270 rats received reduced-size liver transplantation of which 44 died because of intra-abdominal hemorrhages. The distribution of abdominal hemorrhage sites was as follows: 28 cases with anastomotic hemorrhages of the inferior vena cava of the superior liver, 9 cases with subcapsular hemorrhage, 9 cases with tied hemorrhages from the left lateral lobe, 7 cases with hemorrhages from the papillary lobe, 7 hemorrhages from the triangular lobe, 5 hemorrhages of the right suprarenal vein and lumbar veins, 4 hemorrhages caused by mechanical injury, 4 cuff hemorrhages of the portal vein and the inferior vein cava of the inferior liver, 8 anastomotic hemorrhages of the inferior vena cava of the superior liver and the tied hemorrhage of the left outboard lobe, and 5 hemorrhages of the two tied points of the reduced-size liver. Ten hemorrhages were stopped by suture or/and ligature, and 6 were stopped by washing with or soaking in hot water. Results of this study will be helpful to raise success rates of reduced-size liver transplantation.     

A simplified method for metabolic studies in conscious swine

Reliable short-term blood access in conscious swine was provided by implanting multiple silastic catheters. Catheters were inserted into the aorta, hepatic vein, portal vein, and inferior vena cava through a midline laparotomy incision. Multiple catheters also were placed into the external jugular vein through a separate cervical incision. Catheter patency rates for blood withdrawal on the sixth post-operative day were: arterial 100%, hepatic 91%, portal 86%, inferior vena cava 71%. No animal had major wound or catheter infection on the seventh post-operative day. The methods described allow metabolic studies, including measurements of splanchnic blood flow, to be carried out either acutely or for up to at least 7 days post-operatively.     

The Abdominal Circulatory Pump

Blood in the splanchnic vasculature can be transferred to the extremities. We quantified such blood shifts in normal subjects by measuring trunk volume by optoelectronic plethysmography, simultaneously with changes in body volume by whole body plethysmography during contractions of the diaphragm and abdominal muscles. Trunk volume changes with blood shifts, but body volume does not so that the blood volume shifted between trunk and extremities (Vbs) is the difference between changes in trunk and body volume. This is so because both trunk and body volume change identically with breathing and gas expansion or compression. During tidal breathing Vbs was 50–75 ml with an ejection fraction of 4–6% and an output of 750–1500 ml/min. Step increases in abdominal pressure resulted in rapid emptying presumably from the liver with a time constant of 0.61±0.1SE sec. followed by slower flow from non-hepatic viscera. The filling time constant was 0.57±0.09SE sec. Splanchnic emptying shifted up to 650 ml blood. With emptying, the increased hepatic vein flow increases the blood pressure at its entry into the inferior vena cava (IVC) and abolishes the pressure gradient producing flow between the femoral vein and the IVC inducing blood pooling in the legs. The findings are important for exercise because the larger the Vbs the greater the perfusion of locomotor muscles. During asystolic cardiac arrest we calculate that appropriate timing of abdominal compression could produce an output of 6 L/min. so that the abdominal circulatory pump might act as an auxiliary heart.     

Chronic utero-ovarian vein catheterization with subsequent occlusion prolongs the estrous cycle and changes electromyographic activity in the myometrium of ewes

The objective of our study was to determine the effect of chronic utero-ovarian vein catheterization in ewes on estrous cycle length, plasma progesterone (P) concentration, and myometrial electromyographic activity. Cyclic ewes with inferior vena cava catheters were used as controls. Estrus was synchronized in ten ewes and 10 to 12 d following estrus, the ewes were anesthetized, fitted with myometrial electromyograph leads and with utero-ovarian vein (n = 5) or inferior vena cava (n = 5) catheters. After surgery, ewes returned to estrus as expected (16 to 18 d interestrus interval). The second cycle of four of five ewes with utero-ovarian vein catheters were prolonged (40 to 58 d). The inferior vena cava catheterized ewes had normal length second cycles. Plasma P concentrations reflected the estrous cycles: low ( 0.05).     

Simple validation for the hepatic venous cannula implanted chronically in conscious rats

A method for the detection of vena caval contamination in blood taken from hepatic venous cannulas in conscious rats was described. The procedures included 1) bolus injection of tritiated water (50 microCi) through a cannula into the abdominal inferior vena cava and 2) continuous blood sampling (less than 0.2 ml) from the hepatic venous cannula for 2 min into a 180-cm piece of Tygon tubing, starting concurrently with tracer injection. The washout of tritium was determined from samples in 15-cm sections of Tygon tubing. Because circulation from the inferior vena cava to the hepatic vein is interceded by the systemic circulation, the washout of tritium from a valid hepatic venous cannula should resemble the pattern determined elsewhere in the systemic circulation. In the current study, the reference systemic washout was determined in the superior vena cava of a group of rats similarly injected with tritiated water in the inferior vena cava. The maximum of tritium washout derived from a valid hepatic venous cannula should fall in the range encompassed by one standard deviation of the mean of the maximum of the reference (1,400 to 1,930 cpm/sample). The maximum of the washout pattern derived from the invalid cannula, which lay adjacent to the site of injection, was expected to exceed this range. On the basis of these criteria, hepatic blood flow (HBF) was determined by sulfbromophthalein (BSP) extraction in groups of rats with valid and invalid cannulas. HBF in rats with valid hepatic venous cannulas was 2.58 +/- 0.15 in the conscious state and 2.76 +/- 0.26 ml.min-1.g wet wt-1 in the ketamine-anesthetized state.(ABSTRACT TRUNCATED AT 250 WORDS)     

Adrenocortical Carcinoma Invading the Inferior Vena Cava: Case Report And Literature Review

ObjectiveTo present the case of a man with a rightsided adrenocortical carcinoma that invaded the inferior vena cava and was managed by radical resection and vein patch repair.MethodsWe report the clinical, laboratory, imaging, and operative findings, and we highlight the pertinent features of this case. The literature is reviewed for the management of adrenocortical carcinoma in conjunction with inferior vena cava invasion.ResultsIn a 34-year-old man with new-onset abdominal pain, abdominal imaging disclosed a large right adrenal mass with invasion into the inferior vena cava. Laboratory values revealed that the adrenal mass was likely nonfunctional. At surgical intervention with use of cardiopulmonary bypass, the mass was removed en bloc with the adrenal gland, right kidney, and the wall of the inferior vena cava, and the inferior vena cava was reconstructed with bovine pericardium.ConclusionDespite direct invasion or extension of tumor thrombus into the inferior vena cava (or both), complete (R0) resection can be obtained. Thus, this scenario should not preclude attempted curative resection in patients with adrenal cancer. (Endocr Pract. 2008;14: 721-725)     

Gluconeogenesis by the fetal sheep liver in vivo

Hepatic gluconeogenesis is an important source of glucose postnatally. Whether hepatic gluconeogenesis contributes to fetal glucose supply has not been studied directly in vivo. Previous studies of gluconeogenesis in fetal sheep have assessed total fetal glucose production, and the results have been controversial. To assess the specific role of the liver in gluconeogenesis in fetal sheep, we placed catheters in the right or left hepatic vein, umbilical vein and the inferior vena cava of six fetal sheep (mean gestational age 134 days) and infused a radioactive gluconeogenic substrate (14C-lactate or 14C-alanine) into the fetal inferior vena cava. We measured 14C-glucose radioactivity (dpm/ml) in the right or left hepatic vein and calculated the arteriovenous difference in 14C-glucose radioactivity (dpm/ml) across the right or left liver lobe. We found that only 0.35% of the 14C substrates perfusing either the right or the left hepatic lobe of the fetal liver were converted to 14C-glucose. Even when considerable glucose was released by the liver, the percentage of substrates converted to glucose remained very low (maximum 1.7%), indicating that gluconeogenesis did not contribute significantly to the glucose released. We conclude that gluconeogenesis by the fetal liver contributes negligibly to the glucose supply in fetal sheep.     

Thromboses néoplasiques et thromboses cruoriques mécaniques compliquant un cancer du testicule gauche en TEP/TDM au 18FDG

We report the case of a 46-year-old patient with pulmonary embolism complicating thrombosis of the left renal vein and inferior vena cava, which came from a malignant tumor of the left testicle. The case has been elucidated by positron emission tomography with ¹⁸FDG coupled to the CT-scan (PET/CT), performed as part of the etiological assessment of this pulmonary embolism, and anatomical and physiological considerations. The examination revealed ¹⁸FDG uptake in thrombus of the left kidney vein and the inferior vena cava. In view of the anatomy of the left spermatic vein, this finding led to the left testicle, which shows no nuclide uptake but was bathed in a large hydrocele visible on CT images. If several cases of pulmonary embolism or thrombosis of the inferior vena cava revealing a testicular cancer have been described in the literature, there has been no report including ¹⁸FDG PET/CT to the best of our knowledge. This case illustrates the imaging differences between bland and malignant thrombus as a consequence of their pathophysiology. It highlights the contribution of CT images from the PET/CT for the diagnosis.     

大鼠肾移植慢性排斥反应模型的建立

目的建立稳定而可靠的大鼠肾移植慢性排斥反应模型。方法选用30只Wistar大鼠为供体,30只SD大鼠为受体。取供体左肾,采用HC-A离体肾保存液原位灌注,将供肾动、静脉分别与受体腹主动脉、下腔静脉行端侧吻合,以输尿管膀胱植入法行尿路重建,建立大鼠同种异体肾移植模型。分别于术后3、6、9周取移植肾观察大体和组织形态学变化,观察术后并发症及排斥反应情况。结果移植肾脏大体和组织形态学呈渐进性变化,至术后9周可出现明显的慢性排斥反应病理改变。移植肾脏可顺利存活,部分出现肾积水并发症,但不影响排斥反应病理变化。结论本方法可建立稳定、可靠的肾移植慢性排斥反应模型,是研究慢性排斥反应的理想模型。     

HEMIAZYGOS CONTINUATION TO CORONARY SINUS WITH NORMAL LEFT INNOMINATE VEIN

A case is described of absent hepatic segment of the inferior vena cava with hemiazygos continuation and drainage into the coronary sinus with associated atrial septal defect and patent ductus arteriosus. In all previously reported cases of inferior vena caval anomalies with persistent hemiazygos, the hemiazygos joined the homolateral superior vena cava. To our knowledge this is the first case to be reported of a patient who had hemiazygos continuation to the coronary sinus with a normal left innominate vein and a single right superior vena cava.     

Estimation of the Spontaneous Mutation Rate per Nucleotide Site in a Drosophila melanogaster Full-Sib Family

We employed deep genome sequencing of two parents and 12 of their offspring to estimate the mutation rate per site per generation in a full-sib family of Drosophila melanogaster recently sampled from a natural population. Sites that were homozygous for the same allele in the parents and heterozygous in one or more offspring were categorized as candidate mutations and subjected to detailed analysis. In 1.23 × 10⁹ callable sites from 12 individuals, we confirmed six single nucleotide mutations. We estimated the false negative rate in the experiment by generating synthetic mutations using the empirical distributions of numbers of nonreference bases at heterozygous sites in the offspring. The proportion of synthetic mutations at callable sites that we failed to detect was <1%, implying that the false negative rate was extremely low. Our estimate of the point mutation rate is 2.8 × 10⁻⁹ (95% confidence interval = 1.0 × 10⁻⁹ − 6.1 × 10⁻⁹) per site per generation, which is at the low end of the range of previous estimates, and suggests an effective population size for the species of ∼1.4 × 10⁶. At one site, point mutations were present in two individuals, indicating that there had been a premeiotic mutation cluster, although surprisingly one individual had a G→A transition and the other a G→T transversion, possibly associated with error-prone mismatch repair. We also detected three short deletion mutations and no insertions, giving a deletion mutation rate of 1.2 × 10⁻⁹ (95% confidence interval = 0.7 × 10⁻⁹ − 11 × 10⁻⁹).     

Small bowel transplantation in mice

Since 1990, the development of tacrolimus-based immunosuppression and improved surgical techniques, the increased array of potent immunosuppressive medications, infection prophylaxis, and suitable patient selection helped improve actuarial graft and patient survival rates for all types of intestine transplantation. Patients with irreversible intestinal failure and complications of parenteral nutrition should now be routinely considered for small intestine transplantation. However, Survival rates for small intestinal transplantation have been slow to improve compares increasingly favorably with renal, liver, heart and lung. The small bowel transplantation is still unsatisfactory compared with other organs. Further progress may depend on better understanding of immunology and physiology of the graft and can be greatly facilitated by animal models. A wider use of mouse small bowel transplantation model is needed in the study of immunology and physiology of the transplantation gut as well as efficient methods in diagnosing early rejection. However, this model is limited to use because the techniques involved is an extremely technically challenging. We have developed a modified technique. When making anastomosis of portal vein and inferior vena cava, two stay sutures are made at the proximal apex and distal apex of the recipient s inferior vena cava with the donor s portal vein. The left wall of the inferior vena cava and donor s portal vein is closed with continuing sutures in the inside of the inferior vena cava after, after one knot with the proximal apex stay suture the right wall of the inferior vena cava and the donor s portal vein are closed with continuing sutures outside the inferior vena cave with 10-0 sutures. This method is easier to perform because anastomosis is made just on the one side of the inferior vena cava and 10-0 sutures is the right size to avoid bleeding and thrombosis. In this article, we provide details of the technique to supplement the video.     

Effect of chlorpyrifos on healing of cutaneous leishmaniasis lesions after treatment with Pentostam®

The insecticide chlorpyrifos (CPF) is widely used in the Kingdom of Saudi Arabia (KSA) to control agricultural pests. The present work is a preliminary investigation of the effect of CPF on healing of cutaneous leishmaniasis (CL) lesions, caused by Leishmania major in farmers exposed to this insecticide, after treatment with Pentostam^®. Lesion diameters were measured and CPF concentrations in the blood plasma of farmer and non-farmer CL patients in Al-Ahsa were detected by gas chromatography/mass spectrometry/mass spectrometry before and 6 weeks after treatment with Pentostam^®. CPF concentrations in the blood of farmer patients ranged between 4.570 and 7.096 ng/μl (mean = 6.19 ± 0.881 ng/μl) before and after treatment with Pentostam^®. The mean lesion diameter in these patients decreased by a factor of 2.21 after treatment with Pentostam^®; they measured 1.85–11.75 mm, (mean = 6.165 ± 3.500 mm) before treatment and 0.22–6.10 mm (mean = 2.796 ± 2.102 mm) after treatment. Lesion diameter increased exponentially with the increase of CPF concentration in the patients’ blood. CPF was not detected in the non-farmer patients before or after treatment. Their mean lesion diameter decreased by a factor of 6.86 after treatment with Pentostam^®; they measured 1.33–7.10 mm (mean = 2.882 ± 1.764 mm) before treatment and 0.11–0.92 mm (mean = 0.425 ± 0.277 mm) after treatment. The mean lesion diameter in farmer patients was much greater than that of non-farmer patients both before (2.14×) and after (6.657×) treatment with Pentostam^®. Chronic exposure to low levels of the pesticide aggravates the development and delays the healing of CL lesions due to immunotoxicity and/or peripheral neurotoxicity caused by CPF. Further detailed studies would assess CPF effect on the severity of infection with CL in agricultural workers continuously exposed to this insecticide in different areas of KSA in conformity of their finding.     

Dependence of the topography of the hepatic veins on the external shape of the liver, its size and on age

Hepatic preparations obtained from 186 newborns, children and mature persons have been studied. In newborns and babies the size of the right and left hepatic lobes are nearly the same. Beginning from an early age, the right hepatic lobe begins to grow, and the oblongatal or oval form of the liver changes into a triangle one. With changes in its size and form, the topography of the hepatic veins changes, too. In children younger than 1 year of age having the oblongatal or oval form of their liver, the diameters of the right, middle and left hepatic veins are nearly equal. In mature persons having the triangle form of the liver, the right hepatic vein is the largest and its diameter is twice as large as that of the left hepatic vein. Additional hepatic veins flowing into the inferior vena cava, are mainly formed by the branches participating in drainage of the right hepatic lobe. In 25 cases there are additional large hepatic veins; they are observed in cases when the right hepatic vein is poorly developed.     

PGI2 production by rat blood vessels: Diminished prostacyclin formation in veins compared to arteries

Homogenates of eleven different blood vessels from normal Sprague-Dawley rats varied in their ability to produce PGI₂ (i.e., 6-keto-PGF_1α) from [1−¹⁴C]PGH₂. The most notable difference was seen between arteries and veins. Arterial tissues produced more 6-keto-PGF_1α from exogenous PGH₂ than veins at all enzyme (i.e., protein) concentrations tested. Similar results were obtained utilizing different homogenization techniques or arterial and venous rings, indicating this difference was real and not due to homogenization artifacts. In addition, the thoracic segment of the inferior vena cava was more active in converting added [1−¹⁴C]PGH₂ to 6-keto-PGF_1α than the abdominal segment of added inferior vena cava suggestive of a possible segmental distribution of the enzyme activity in blood vessels. These results may be interpreted as indicating that PGI₂ may have a vasomotor function for blood vessels in addition to its proposed antithrombotic role.     

Efficacy and Safety of Right Hemihepatectomy Through the Right Retrohepatic Tunnel

We wished to study the efficacy and safety of the retrograde ligation of short hepatic veins (SHVs) and the right hepatic vein (HV) through the retrohepatic tunnel in patients who underwent hemihepatectomy due to large hepatic carcinoma in the right lobe of the liver. Right hemihepatectomy was performed in 23 patients with tumors larger than 8 cm in diameter. The liver was separated at the secondary porta, and the interspace between right HVs and middle HVs was expanded. The right hepatic portal vein and hepatic artery were freed and ligated, followed by the retrograde dissection of SHVs and the right HV along the right retrohepatic space anterior to the inferior vena cava. A blocking belt was set at the left side of the midline, after which the right liver was cut off. The procedure was successfully completed in all patients. The average amount of intraoperative blood loss was 640 ml. The change in hepatic function was observed on the third postoperative day. Twenty-two patients exhibited satisfactory results; one patient died from postoperative hepatic failure. In conclusion, this procedure can be safely performed in most hemihepatectomy patients with liver tumors.     

Sensitivity of Plasmodium falciparum to Antimalarial Drugs in Hainan Island,China

Pyronaridine and artesunate have been shown to be effective in falciparum malaria treatment. However, pyronaridine is rarely used in Hainan Island clinically, and artesunate is not widely used as a therapeutic agent. Instead, conventional antimalarial drugs, chloroquine and piperaquine, are used, explaining the emergence of chloroquine-resistant Plasmodium falciparum. In this article, we investigated the sensitivity of P. falciparum to antimalarial drugs used in Hainan Island for rational drug therapy. We performed in vivo (28 days) and in vitro tests to determine the sensitivity of P. falciparum to antimalarial drugs. Total 46 patients with falciparum malaria were treated with dihydroartemisinin/piperaquine phosphate (DUO-COTECXIN) and followed up for 28 day. The cure rate was 97.8%. The mean fever clearance time (22.5±10.6 hr) and the mean parasite clearance time (27.3±12.2 hr) showed no statistical significance with different genders, ages, temperatures, or parasite density (P>0.05). The resistance rates of chloroquine, piperaquine, pyronarididine, and artesunate detected in vitro were 71.9%, 40.6%, 12.5%, and 0%, respectively (P<0.0001). The resistance intensities decreased as follows: chloroquine>piperaquine>pyronarididine>artesunate. The inhibitory dose 50 (IC₅₀) was 3.77×10^-6 mol/L, 2.09×10^-6 mol/L, 0.09×10^-6 mol/L, and 0.05×10^-6 mol/L, and the mean concentrations for complete inhibition (CIMC) of schizont formation were 5.60×10^-6 mol/L, 9.26×10^-6 mol/L, 0.55×10^-6 mol/L, and 0.07×10^-6 mol/L, respectively. Dihydroartemisinin showed a strong therapeutic effect against falciparum malaria with a low toxicity.     

Influence of spatial distribution and size of clones on the realized outcrossing rate of the marsh cinquefoil (Comarum palustre)

Background and Aims

Clonal growth is a common feature in flowering plants. As clone size increases, the selfing rate in self-compatible species is likely to increase due to more frequent geitono-pollination events (i.e. pollination among flowers within the same genet). This study investigated the breeding system of the marsh cinquefoil (Comarum palustre) and assessed spatial distribution of clones, clone size and architecture, and their effects on realized outcrossing rates. In addition, pollen dispersal was investigated in two patchy populations.

Methods

The species'' breeding system was investigated under controlled conditions through hand pollinations (self- vs. cross-pollination). Using microsatellite markers, an assessment was made of the realized outcrossing rates and the genetic diversity in four natural populations, the clonal structure in two populations within five 15 × 15 m sampling plots following 0·5 × 0·5 m grids, and the pollen dispersal through paternity assignment tests in those two populations.

Key Results Comarum palustre

is a self-compatible species but only presents a low rate of spontaneous self-pollination. The occurrence of inbreeding depression was not detected at the seed set stage (δ_SS = 0·04). Clones were spatially clumped (A_C = 0·60–0·80), with intermediate to no intermingling of the ramets (D_C = 0·40–1·00). Genet size ranged from one to 171 ramets. Patchy populations had low outcrossing rates (t_m = 0·33–0·46). Large clones showed lower outcrossing rates than small clones. Pollen dispersal mainly occurred within patches as only 1–7 % of the pollination events occurred between patches of >25 m separation. Seedling recruitment events were detected.

Conclusions

Genet size together with distances between patches, through increasing geitono-pollination events, appeared to be important factors influencing realized outcrossing rates. The study also revealed seed flow allowing seedling recruitment, which may contribute to increasing the number of new patches, and potentially further enhance gene flow within populations.     

A Canine Model for IVC Occlusive Form of Budd–Chiari Syndrome Using Endovascular Technique

The objective of this study was to assess the portal/hepatic changes in a newly designed canine model for Budd–Chiari syndrome (BCS). The inferior vena cava (IVC) was occluded using a diagram stent under general anesthesia in 10 mongrel dogs under the guidance of percutaneous angiography. Five dogs that received IVC angiography only were used as sham controls. Occlusion of the IVC increased the diameter of the hepatic veins, portal vein, and IVC. Massive ascites, significantly increased abdominal circumference, varying degrees of esophageal varices, congestion, cirrhosis, and fibrosis of the liver were also noted. BCS could be readily established by placing a diaphragm–stent in the IVC via a percutaneous endovascular approach.