End Of Vein Research Articles

Creation of 6-10mm Diameter Transjugular Intrahepatic Portosystemic Shunts Using a Novel TIPS Stent Graft in a Swine Model

PurposeTo assess the delivery, function, and patency of a new expanded polytetrafluoroethylene encapsulated TIPS stent- graft ("Liverty") in an animal model. Materials and MethodsTIPS were created in 2 successive groups: 14 single & 10 overlapping devices, in swine weighing 52-64kg. Explants occurred at 30 (n=10) and 60 (n=14) days. These were evaluated by histomorphometry and histopathologic evaluations, and electron microscopy. ResultsSeven 6mm, five 7mm, and twelve 10mm diameter TIPS were created using varied human TIPS access sets without complications; both sheathed and unsheathed advancement and deployment of the devices within liver tracts. One animal was sacrificed at 35d due to encephalopathy; remainder survived to endpoints. 22/24 TIPS were patent at 30 and 60-day endpoints; Mean stenosis at 30 days was 13.3% +/- 10.1%, and for 60 days was 18.44% ± 5.04%. Two shunts were occluded by tissue overgrowth at unstented native hepatic vein end and downgrowth into TIPS. Histology and electron microscopy showed well-apposed, incorporated devices lined with smooth, uniform neointimal tissue averaging 0.48mm (single devices) and 0.74mm thick (overlapped devices) with minimal adventitial inflammation. ConclusionThe new Liverty TIPS stent graft was straightforward to deploy for TIPS creation and resulted in patent 6,7, and 10mm diameter shunts in both single and overlapping configurations. One- and 2-month histology showed desired tissue healing without in-stent stenosis.

Haemodynamic study of left nonthrombotic iliac vein lesions: a preliminary report

Nonthrombotic iliac vein lesions (NIVLs) are significant causes of chronic venous insufficiency (CVI) in the left lower limb and symptom recurrence following left lower limb varicose vein treatment. The goal of this study was to explore the haemodynamic and morphological characteristics of iliac veins in patients with NIVLs. Pressure at the caudal end of the stenotic left common iliac vein (LCIV) segment, local blood flow velocity, and time-averaged wall shear stress in the stenotic segment exhibited positive correlations with the clinical CVI classification (R = 0.92, p < 0.001; R = 0.94, p < 0.001; R = 0.87, p < 0.001), while the relative retention time showed a negative correlation (R = -0.94, p < 0.001). The pressure difference (∆P) between the two ends of the stenotic segment and the velocity difference (∆V) between the stenotic segment and the caudal end were positively correlated with the clinical classification (R = 0.92, p < 0.001; R = 0.9, p < 0.001). The cross-sectional area stenosis rate and length of the stenotic LCIV segment were positively correlated with the clinical classification (R = 0.93, p < 0.001; R = 0.63, p < 0.001). The results suggest that haemodynamic assessment of the iliac vein could effectively portray blood flow disturbances in stenotic segments of the LCIV, potentially reflecting the degree of iliac vein stenosis. Haemodynamic indicators are correlated with the severity of clinical CVI symptoms.

Intrahepatic distribution of nerves in Suncus murinus by whole-mount immunohistological observation.

In recent years, elucidating the actual state of the liver nervous system has attracted attention, owing to clinical needs, such as liver transplantation. Conventional methods for studying the intrahepatic nerve distribution mostly use liver tissue sections, specific markers for immunohistological studies, or anterograde/retrograde tracing in animals. However, knowledge of the three-dimensional structure of intrahepatic innervation is vague or speculative. In this study, Suncus murinus (Suncus) (n = 10) were perfused and fixed, the livers were excised, and the liver parenchyma was carefully removed, leaving only the intrahepatic vasculature. Specimens were prepared to study the three-dimensional structure of Suncus intrahepatic and hilar innervation by whole-mount immunohistochemical staining using a neurofilament protein antibody. After the nerves running along the intrahepatic arterial system entered the liver parenchyma from the hepatic hilum, they maintained a relatively rich distribution along the interlobular arteries until the distal end. The innervation of the portal system began to decrease after entering the liver parenchyma and decreased significantly after reaching the deep parts. By the time it reached the end of the interlobular vein, there was very little left. The number of nerves running along the intrahepatic bile duct system was significantly reduced after entering the porta hepatis, and innervation was difficult to observe after completely entering the liver parenchyma. Whole-mount immunohistochemical analyses with an anti-NFP antibody showed that intrahepatic innervation mainly accompanied the hepatic interlobular arteries and extended to their terminal ends. Neuronal regulation is very important in the functional regulation of intrahepatic nutritional vessels. However, there were very few NFP-immunoreactive nerves accompanying the intrahepatic bile duct system, possibly suggesting that the functional regulation of the intrahepatic biliary system mainly relies on hormones and neuropeptides.

Exploring laser-induced acute and chronic retinal vein occlusion mouse models: Development, temporal in vivo imaging, and application perspectives.

Photodynamic venous occlusion is a commonly accepted method for establishing mouse models of retinal vein occlusion (RVO). However, existing model parameters do not distinguish between acute and chronic RVO subtypes. Large variations in laser energy seem to correlate with fluctuating retinopathy severity and high rates of venous recanalization during the acute phase, along with the variable levels of retinal perfusion during the chronic phase. After optimizing the modeling procedure and defining success and exclusion criteria, laser energy groups of 80mW, 100mW, and 120mW were established. Multimodal imaging confirmed that higher energy levels increased the incidence of retinal cystoid edema and intraretinal hemorrhage, exacerbated the severity of exudative retinal detachment, and reduced the venous recanalization rate. For the acute model, 100mW was considered an appropriate parameter for balancing moderate retinopathy and venous recanalization. Continuous imaging follow-up revealed that day 1 after RVO was the optimal observation point for peaking of retinal thickness and intensive occurrence of retinal cystic edema and intraretinal hemorrhage. After excluding the influence of venous recanalization on retinal thickness, acute retinal edema demonstrated a positive response to standard anti-vascular endothelial growth factor therapy, validating the clinical relevance of the acute RVO model for further study in pathogenic mechanisms and therapeutic efficacy. For the chronic model, the 120mW parameter with the lowest venous recanalization rate was applied, accompanied by an increase in both photocoagulation shots and range to ensure sustained vein occlusion. Imaging follow-up clarified non-ischemic retinopathy characterized by tortuosity and dilation of the distal end, branches, and adjacent veins of the occluded vein. These morphological changes are quantifiable and could be combined with electrophysiological functional assessment for treatment effectiveness evaluation. Moreover, the stable state of venous occlusion may facilitate investigations into response and compensation mechanisms under conditions of chronic retinal hypoperfusion.

The Enhancement of Skills Through Eco-Printing Training With Pounding Technique Among PKK Groups in Bangunjiwo Village, Bantul

The objective of this Community Service Program (PkM) is to enhance the skills in creating ecoprinting products using the pounding technique for small business owners or novice entrepreneurs, specifically the PKK women’s group in Bangunjiwo Village, Bantul. This program involves twenty participants and a ten-member organizing committee from UNY's Vocational Faculty's Fashion Design Study Program, including five lecturers and five students. The stages of the PkM activities include needs analysis, preparation, implementation, and evaluation, conducted from March to June 2023. The outcomes of the PkM activities indicate that the feedback from the ecoprinting instructors using the pounding technique averaged 4.2 out of 5.0, categorized as good. The increase in participants' knowledge was obtained with an average N-gain value of 0.56 (56.27%) which was categorized as quite effective. The creativity of the products produced had an average score of 84.5 out of 100. Specific skills that need to be considered to produce high-quality products include recognizing the characteristics and experimental treatment of certain leaves, the type of surface of the pounding tool, the position, and accuracy on the stem and vein ends of the leaves, fabric dyeing strategies, and the patterns produced, as well as drying the fabric naturally or by air-drying. Another important aspect is the creativity in arranging leaves to achieve high artistic value and meaningful aesthetics. The quality of ecoprinting products using the pounding technique requires repeated training and experimentation to produce varied colors from leaf pigments and to select leaves with unique and interesting patterns.

Foliar Anatomy of the Family Acanthaceae I. the Tribe Justiceae

The venation type, areole size, vein endings, vein tips and epidermal character have been described in 11 species of the tribe Justiceae of the family Acanthaceae. The features like unilacunar node, a prominent strand, venation patterns, structure of the epidermis, diamesogenous stomata, trichomes, lithocysts, etc. have been found to be useful in taxonomic considerations.

Gross anatomy of vascular supply and drainage of mammary fat pads in mice models.

This work extensively studied the vasculature of mice mammary fat pads (BALB/c and C57BL/6) with special reference to haematogenous drainage routes. Mammary fat pads were five pairs (first cervical, second and third thoracic, fourth abdominal and fifth inguinal), bilaterally symmetrical, extending laterally and continuously with the subcutaneous fascia. The superficial cervical artery and vein primarily accomplished the blood vasculature of the first mammary fat pad, while the lateral thoracic and external thoracic arteries and veins supplied the second and third mammary fat pads. The superficial cervical vein (found parallel to the superficial cervical artery) drained into the external jugular vein. The lateral thoracic artery and external thoracic artery branched almost at the same level as the axillary artery (branch of subclavian artery), the latter being more medial in position. However, in some specimens, the branching of both arteries appeared to be at the same level, and their origins were indistinguishable. The lateral thoracic vein that was parallel to the lateral thoracic artery drained to the axillary vein close to the drainage of the external thoracic vein. The lateral thoracic, superficial caudal epigastric, iliolumbar and external thoracic arteries and veins vascularized the fourth mammary fat pad and displayed anastomosis among themselves. The iliolumbar vein (found parallel to the iliolumbar artery) drained into the inferior vena cava. The superficial caudal epigastric vein (found parallel to the superficial caudal epigastric artery (SCaEA)) drained into the femoral vein. Unlike humans, the internal thoracic artery and vein did not participate in the vasculature of mammary fat pads. The SCaEA and vein supplied blood and drained the fifth mammary fat pad. The anatomical continuity of the fourth and fifth mammary fat pads provided common drainage for both mammary fat pads. The BALB/c and C57BL/6 mice strains studied did not differ in topography and size of mammary fat pads. The vascular supply and drainage of the mammary fat pads also did not differ in the strains studied. Only minor variations could be noted in the small veins draining into the lateral thoracic vein. Lateral tributaries seen in the terminal end of the lateral thoracic vein were absent in the C57BL/6 mice.

Computational fluid-structure interaction analysis of the end-to-side radio-cephalic arteriovenous fistula

Background and ObjectiveIn the current work, we present a descriptive fluid-structure interaction computational study of the end-to-side radio-cephalic arteriovenous fistula. This allows us to account for the different thicknesses and elastic properties of the radial artery and cephalic vein. MethodsThe core of the work consists in simulating different arteriovenous fistula configurations obtained by virtually varying the anastomosis angle, i.e. the angle between the end of the cephalic vein and the side of the radial artery. Since the aim of the work is to understand the blood dynamics in the very first days after the surgical intervention, the radial artery is considered stiffer and thicker than the cephalic vein. ResultsOur results demonstrate that both the diameter of the cephalic vein and the anastomosis angle play a crucial role to obtain a blood dynamics without re-circulation regions that could prevent fistula failure. ConclusionsWhen an anastomosis angle close to the perpendicular direction with respect to the radial artery is combined with a large diameter of the cephalic vein, the recirculation regions and the low Wall Shear Stress (WSS) zones are reduced. Conversely, from a structural point of view, a low anastomosis angle with a large diameter of the cephalic vein reduces the mechanical stress acting on the vessel walls.

Outcomes of AV fistula formation for dialysis patients using interrupted sutures one-year single center study.

To document the Outcomes of AV fistula formation for dialysis patients using interrupted sutures. In this Cross-sectional study conducted at PNS Shifa Karachi, from June 2022 to June 2023, patients above 18 years of age, male or female, with ESRD/CKD were included. After clinical screening and ultrasound doppler, the distal most part of wrist was considered as a site for radio cephalic AVF. Operation was performed under surgical loupe with 4.5x magnification. Standard incision of about 4-5 cm oblique proximal to the wrist crease was given at the volar surface on the radial side of Distal forearm, extending till the lateral side up to the snuffbox. Subcutaneous tissue was incised and dissection was done to identify the cephalic vein and radial artery. Distal most end of the cephalic vein was ligated using vicryl 4-0 suture and cephalic vein dissected free from the underling tissue to mobilize it up to the radial artery. During the study N=35 patients who required AVF creation visited the department. The mean age of the study participants was 59.34±15.48. If thrill at the site of AVF and backflow at cut end of cephalic vein were present the surgeons were satisfied, higher satisfaction among the surgeon was achieved in the AVF created at brachiocephalic artery while the diameter of vessels didn't contribute in surgeon satisfaction. Presence of thrill at the site of AVF and backflow at cut end of cephalic vein have strong association with good prognosis of AVF.

Heterotopic Auxiliary Whole Liver Rat Transplant Model Utilizing a Hepaticoureterostomy for Allograft Rejection Studies.

Small animal transplant models are indispensable for organ tolerance studies investigating feasible therapeutic interventions in preclinical studies. Rat liver transplantation (LTx) protocols typically use an orthotopic model where the recipients' native liver is removed and replaced with a donor liver. This technically demanding surgical procedure requires advanced micro-surgical skills and is further complicated by lengthy anhepatic and lower body ischemia times. This prompted the development of a less complicated heterotopic method that can be performed faster with no anhepatic or lower body ischemia time, reducing post-surgery stress for the recipient animal. This heterotopic LTx protocol includes two main steps: excising the liver from the donor rat and transplanting the whole liver into the recipient rat. During the excision of the donor liver, the surgeon ligates the supra-hepatic vena cava (SHVC) and hepatic artery (HA). On the recipient side, the surgeon removes the left kidney and positions the donor liver with the portal vein (PV), infra-hepatic vena cava (IHVC), and bile duct facing the renal vessels. Further, the surgeon anastomoses the recipient's renal vein end to end with the IHVC of the liver and arterializes the PV with the renal artery using a stent. A hepaticoureterostomy is utilized for biliary drainage by anastomosing the bile duct to the recipient's ureter, permitting the discharge of bile via the bladder. The average duration of the transplantation was 130 min, cold ischemia duration was around 35 min, and warm ischemia duration was less than 25 min. Hematoxylin and eosin histology of the auxiliary liver from syngeneic transplants showed normal hepatocyte structure with no significant parenchymal alterations 30 days post-transplant. In contrast, 8-day post-transplant allogeneic graft specimens demonstrated extensive lymphocytic infiltration with a Banff Schema rejection activity index score of 9. Therefore, this LTx method facilitates a low morbidity rejection model alternative to orthotopic LTx.

Supercharging DIEP Flaps Using Contralateral Superficial Inferior Epigastric Vein Grafts

Introduction: Venous congestion, even with a patent deep venous anastomosis, can afflict some DIEP (Deep Inferior Epigastric Perforator) flaps and various techniques of superficial venous supercharging have been described, although the indications for its use are not consensual. The main goal of this study is to confirm that superficial venous supercharge of DIEP flaps, utilizing the contralateral Superficial Inferior Epigastric Vein (SIEV) as an interposition vein graft, is feasible and functional. Materials and Methods: We retrospectively reviewed all DIEP flap breast reconstruction patients treated at our institution between June 2016 and December 2017 and that met all the inclusion criteria: Unilateral breast reconstruction with a DIEP flap; flap weighing more than 750 gm; supercharging of the ipsilateral superficial venous system; contralateral SIEV interposition graft; implantable doppler probe in the superficial system for at least 5 days. In the technique described here, the contralateral SIEV graft was harvested and anastomosed to the ipsilateral SIEV, obtaining this way a long vein that easily reaches the recipient vein (distal end of the Internal Mammary Vein - IMV). A Doppler probe was implanted in the superficial system, for at least 5 postoperative days, to monitor the function of this supercharging. We also analyzed the patient’s history, flaps weight, number and perforator rows, recipient vessels, SIEV graft length and diameter and all perioperative complications. Results: Ten patients met all inclusion criteria. They were treated using this technique and analyzed. Two patients had some type of alteration of the Doppler signal and clinical signs of venous congestion. They were surgically revised with success and were analyzed in detail. No total or partial flap failures were found. Clinical fat necrosis was also absent. Conclusion: This technique seems to be feasible, functional and adds an extra length to ipsilateral SIEV to reach a recipient vein. This way, the flap inset is not compromised by a short SIEV. No further significant morbidity is added for SIEV harvest that is in the same operative field, unlike the saphenous or cephalic veins. In selected patients, it could be an alternative supercharging technique.

Effectiveness of Rex shunt for improving the abnormal portal hemodynamics and portal venous pathology in EHPVO animal model.

To investigate the feasibility of the re-patent EHPVO (r-EHPVO) as an animal model of Rex shunt and the effectiveness of Rex shunt in improving abnormal portal hemodynamics and portal venous pathology of EHPVO. A total of 18 New Zealand white rabbits were randomly divided into three groups: normal control (NC) group, extrahepatic portal venous obstruction (EHPVO) group, and r-EHPVO group. The main portal vein was dissected only in the NC group. The main portal vein was narrowed by a cannula in the EHPVO group. The cannula narrowing the main portal vein was removed to restore the portal blood flow into the liver on day 14 in the r-EHPVO group. The portal pressure, splenic size, blood flow velocity, and diameter of the portal vein were measured on days 14 and 28. The shear stress (SS) and circumferential stress (CS) of the portal vein were calculated. The proximal end of the main portal vein was collected on day 28 for further pathological analysis, and the thickness and area of the intima and media were measured by Image J software. The portal pressure, splenic size, SS, CS, intima and media thickness, the ratio of intimal to medial area (I/M), and the ratio of intimal area to the sum of intimal and medial area (I/I + M) were compared among the three groups. The correlation between SS and intimal thickness and between CS and medial thickness were analyzed. On day 28, the portal pressure of the EHPVO group was significantly higher than that of the NC and r-EHPVO groups, but no significant difference was detected in the portal pressure between r-EHPVO and NC groups. The length and thickness of the spleen in the EHPVO and r-EHPVO groups were significantly higher than those in the NC group (P < 0.01) but were significantly lower in the r-EHPVO group than those in the EHPVO group (P < 0.05). The SS was significantly lower in the EHPVO group than in NC and r-EHPVO groups (P < 0.05) but was significantly higher in the NC group than in the r-EHPVO group (P = 0.003). The CS was significantly higher in the EHPVO and r-EHPVO groups than that in the NC group (P < 0.05) but was significantly lower in the r-EHPVO group than that in the EHPVO group (P < 0.001). The intimal thickness, I/M, and I/I + M of the EHPVO group were significantly higher than those of the NC and r-EHPVO groups (P < 0.05), but no significant difference was observed between the NC and r-EHPVO groups (P > 0.05). The SS is negatively related to intimal thickness (r = - 0.799, P < 0.001). The r-EHPVO model is feasible as an animal model of the Rex shunt. The Rex shunt could be beneficial to improving the abnormal portal hemodynamic and portal venous intimal hyperplasia by restoring the portal blood flow into the liver.

Comparison of different anastomosis angles in radiocephalic fistula with modified functional end-to-side anastomosis

ObjectiveFunctional vein end to arterial side (ETS) anastomosis uses vein side to arterial side anastomosis with distal vein ligation, which is different from traditional ETS anastomosis. To date, there are no studies concerning different anastomotic angles of fistula with functional ETS anastomosis. The purpose of the study was to analyze the clinical outcomes concerning different anastomotic angles of functional ETS anastomosis in radiocephalic fistula.MethodsBetween January 2018 and December 2020, we performed a prospective cohort study concerning functional ETS anastomosis in radiocephalic fistula. According to vascular anatomy of patients, the anastomosis angles of fistula were designed at 30 ≤ angle ≤ 50°, 50 < angle ≤ 70°, and 135° smooth obtuse angle. The end points were the primary patency rate (PPR), the secondary patency rate (SPR) and the cumulative rate of reintervention (CRR) near anastomotic venous segment.Results124 patients with functional ETS anastomosiss were enrolled in this study. Pearson χ2 test showed that the group of 135°anastomosis angle had the maximum distance between arteries and veins, and the group of 30–50°anastomosis angle had the minimum distance between arteries and veins (P < 0.01). 30–50°anastomosis angle had the highest PPR at 12 months (P = 0.03) and the lowest CRR near anastomotic venous segment at 3 months (P = 0.04) and 12 months (P = 0.01). There were no significant differences among different anastomosis angles concerning the SPR within 12 months (P > 0.05). Kaplan–Meier and log-rank analysis showed that 30–50°anastomosis had the highest PPR (P = 0.03) and the lowest CRR near anastomotic venous segment (P = 0.01). A multivariable Cox model showed anastomotic angle was an independent factor predictive of the PPR (P = 0.04) and the CRR near anastomotic venous segment (P = 0.03). 50–70°anastomosis angle was a risk factor of decreasing PPR (P = 0.03). 50–70° (P = 0.01) and 135° (P = 0.03) anastomosis angle were both obvious risk factors of increasing CRR near anastomotic venous segment.Conclusion30–50°were the best anastomotic angles for functional ETS anastomosis, which had the highest PPR and lowest CRR near anastomotic venous segment.

Protection of the marginal mandibular branches of the facial nerves by different surgical procedures in comprehensive cervical lymphadenectomy for locally advanced oral and oropharyngeal cancer: a multicenter experience

ObjectiveAccording to the different characteristics of patients and cervical lymph node metastasis of oral and oropharyngeal cancer, the marginal mandibular branches of facial nerves were treated by different surgical procedures, and the safety and protective effects of different surgical procedures were investigated.MethodsOne hundred ninety-seven patients with oral and oropharyngeal cancer satisfying the inclusion criteria were selected. According to the different characteristics of patients and cervical metastatic lymph nodes, three different surgical procedures were used to treat the marginal mandibular branches of the facial nerve: finding and exposing the marginal mandibular branches of the facial nerves at the mandibular angles of the platysma flaps, finding and exposing the marginal mandibular branches of facial nerves at the intersections of the distal ends of facial arteries and veins with the mandible, and not exposing the marginal mandibular branches of the facial nerves. The anatomical position, injury, and complications of the marginal mandibular branches of the facial nerves were observed.ResultsThe marginal mandibular branches of the facial nerves were found and exposed at the mandibular angles of the platysma flaps in 102 patients; the marginal mandibular branches of facial nerves were found and exposed at the intersections of the distal ends of the facial arteries and veins with the mandibles in 64 patients; the marginal mandibular branches of facial nerves were not exposed in 31 patients; among them, four patients had permanent injury of the marginal mandibular branches of the facial nerves, and temporary injury occurred in seven patients. There were statistically significant differences in the protection of the mandibular marginal branch of the facial nerve among the three different surgical methods (P = 0.0184). The best protective effect was to find and expose the mandibular marginal branch of the facial nerve at the mandibular angle of the platysma muscle flap, and the injury rate was only 2.94%.ConclusionThe three different surgical procedures were all safe and effective in treating the marginal mandibular branches of the facial nerves, the best protective effect was to find and expose the mandibular marginal branch of the facial nerve at the mandibular angle of the platysma muscle flap.

Xylem conduit deformation across vascular plants: anevolutionary spandrel or protective valve?

The hydraulic system of vascular plants and its integrity is essential for plant survival. To transport water under tension, the walls of xylem conduits must approximate rigid pipes. Against this expectation, conduit deformation has been reported in the leaves of a few species and hypothesized to function as a 'circuit breaker' against embolism. Experimental evidence is lacking, and its generality is unknown. We demonstrated the role of conduit deformation in protecting the upstream xylem from embolism through experiments on three species and surveyed a diverse selection of vascular plants for conduit deformation in leaves. Conduit deformation in minor veins occurred before embolism during slow dehydration. When leaves were exposed to transient increases in transpiration, conduit deformation was accompanied by large water potential differences from leaf to stem and minimal embolism in the upstream xylem. In the three species tested, collapsible vein endings provided clear protection of upstream xylem from embolism during transient increases in transpiration. We found conduit deformation in diverse vascular plants, including 11 eudicots, ginkgo, a cycad, a fern, a bamboo, and a grass species, but not in two bamboo and a palm species, demonstrating that the potential for 'circuit breaker' functionality may be widespread across vascular plants.

Флуктуирующая асимметрия листьев рябины обыкновенной (Sorbus aucuparia L.) как биоиндикатор аэротехногенного загрязнения города Оренбурга

An assessment of environmental pollution in the city of Orenburg was conducted using the fluctuating asymmetry method. The common mountain ash was chosen as an environ­mental indicator. Leaf collection took place at seven points in the city with varying anthropo­genic loads. The research aimed to determine the impact of aerotechnogenic pollution on the magnitude of the fluctuating asymmetry of the leaf blade of the populations of mountain ash within the city of Orenburg. The study revealed that the leaf blades of mountain ash in urban conditions are affected by anthropogenic factors, experiencing air pollution and accumulating harmful substances. The fluctuating asymmetry method can be used as an indicator of plant development instability in urban ecosystems. Elevated environmental stress, based on the integral indicator of fluctuating asymmetry, was noted at all points except the Ural River Embankment. In this area, the growing conditions for plants were characterized as satisfacto­ry. Through pairwise correlation analysis of the examined characteristics, the closest connec­tions were found between two pairs: the width of the leaf half — the distance between the ba­ses of the first and second order veins; the distance from the base of the leaf plate to the end of the second-order vein — the angle between the main vein and the second from the base of the leaf.

Effect of placenta previa on umbilical cord hematocrit value

Objective Placenta previa is one of the causes of neonatal anemia. This condition is mainly explained by antenatal hemorrhage and incision of the anteriorly located placenta during cesarean section. However, the mechanism of neonatal anemia in placenta previa has not been extensively studied or well elucidated. This study investigates whether placenta previa is associated with lower hematocrit levels in newborns with no antenatal hemorrhage and placental incision. Key findings This prospective study investigated 47 patients with previa and 43 control patients who gave birth with a cesarean section at 34–38 weeks of gestation. Blood samples were obtained from the fetal end of the umbilical vein. The mean umbilical cord hematocrit value was 49.3% in the control patients and 46.7% in the patients with previa, and the difference was statistically significant (p = .029). No significant association was observed between hematocrit value and birth weight, gestational age, newborn gender, placenta position, or preoperative maternal hemoglobin level. Conclusion The study findings reveal that even if not complicated by antepartum or intrapartum hemorrhage, placenta previa may be associated with lower hematocrit values in newborns. Although in none of the cases, the umbilical cord hematocrit value was not as low as to be defined as anemia, this effect of previa on newborns should be considered because of the importance of iron status.

Influence of different portal vein branches on hepatic encephalopathy during intrahepatic portal shunt via jugular vein.

This letter is regarding the study titled ‘Targeted puncture of left branch of intrahepatic portal vein in transjugular intrahepatic portosystemic shunt (TIPS) to reduce hepatic encephalopathy’. Prior to the approval of TIPS dedicated stents (Viatorr stents) in China in October 2015, Fluency covered stents were typically used. As Fluency covered stents have a strong support force and axial elastic tension, a ‘cap’ may form if the stent is located too low at the end of the hepatic vein or too short at the end of the portal vein during surgery, leading to stent dysfunction. Since the blood shunted by the stent is from the main trunk of the portal vein, the correlation between the incidence of postoperative hepatic encephalopathy and the location of the puncture target (left or right portal vein branch) is worth discussion. Notably, no studies in China or foreign countries have proven the occurrence of left and right blood stratification after the accumulation of splenic vein and mesenteric blood flow in the main trunk of the portal vein in patients with cirrhotic portal hypertension.

Plasma metabolomics in a deep vein thrombosis rat model based on ultra-high performance liquid chromatography-electrostatic field orbitrap high resolution mass spectrometry

深静脉血栓(DVT)是一种血栓栓塞性疾病,具有高发病率、高死亡率和高后遗症3大特点。采用左股静脉不完全结扎加高渗盐水刺激建立DVT大鼠模型,使用超高效液相色谱-静电场轨道阱高分辨质谱(UHPLC-Orbitrap HRMS)检测假手术组与DVT模型组的血浆代谢谱,用主成分分析(PCA)及正交偏最小二乘-判别分析(OPLS-DA)对代谢组数据进行多元统计分析,观察两组间的代谢表型差异,将多变量模型分析中的变量重要性值(VIP>1)以及代谢物在模型组中的变化倍数(FC≤0.5或FC≥2,且P<0.05)作为差异代谢物筛选条件。最终在DVT模型组与假手术组间筛选得到27种差异代谢物,这些代谢物反映了DVT大鼠的代谢紊乱情况。具体表现为与假手术组相比,DVT模型组中三甲基胺氮氧化物(TMAO)、维生素K、鹅去氧胆酸、牛磺酸、1-甲基烟酰胺、7-酮胆固醇、反式十六烷基-2-烯醇肉碱、乙烯基乙酰甘氨酸、丙酰脯氨酸、咪唑乙酸、咪唑乙酸核糖苷、1,3,7-三甲基尿酸、1-丁胺、2-羟基异丙酸、吡哆醛、5α-四氢皮质酮、苯乳酸的水平显著升高;而3-脱氢肉碱、磷脂酰胆碱22∶6/20∶2(PC 22∶6/20∶2)、甘油二酯18∶3/20∶4(DG 18∶3/20∶4)、溶血磷脂酰胆碱20∶2(LysoPC 20∶2)、波维酸、鹅肌肽、L-肌肽、辛酸、羟基丙酮酸、3-羟基癸酸的水平显著降低。基于京都基因与基因组百科全书数据库(KEGG)代谢通路的差异丰度(DA)分析显示DVT模型大鼠与假手术组的代谢通路差异主要集中在初级胆汁酸生物合成、胆汁分泌、组氨酸代谢、亚油酸代谢、甘油磷脂代谢和β-丙氨酸代谢。紊乱的代谢物和代谢途径可为进一步深入理解DVT的病理机制、寻找诊断标志物及药物作用靶点提供参考。

Establishment and Evaluation of a Porcine Vein Graft Disease Model.

Venous graft disease (VGD) is the leading cause of coronary artery bypass graft (CABG) failure. Large animal models of CABG-VGD are needed for the investigation of disease mechanisms and the development of therapeutic strategies. To perform the surgery, we enter the cardiac chamber through the third intercostal space and carefully dissect the internal mammary vein and immerse it in normal saline. The right main coronary artery is then treated for ischemia. The target vessel is incised, a shunt plug is placed, and the distal end of the graft vein is anastomosed. The ascending aorta is partially blocked, and the proximal end of the graft vein is anastomosed after perforation. The graft vein is checked for patency, and the proximal right coronary artery is ligated. CABG surgery is performed in minipigs to harvest the left internal mammary vein for its use as a vascular graft. Serum biochemical tests are used to evaluate the physiological status of the animals after surgery. Ultrasound examination shows that the proximal, middle, and distal end of the graft vessel are unobstructed. In the surgical model, turbulent blood flow in the graft is observed upon histological examination after the CABG surgery, and venous graft stenosis associated with intimal hyperplasia is observed in the graft. The study here provides detailed surgical procedures for the establishment of a repeatable CABG-induced VGD model.