Effect of major liver resection on hepatic ureagenesis in humans

2007 ◽  
Vol 293 (5) ◽  
pp. G956-G962 ◽  
Author(s):  
Marcel C. G. van de Poll ◽  
Stephen J. Wigmore ◽  
Doris N. Redhead ◽  
Regina G. H. Beets-Tan ◽  
O. James Garden ◽  
...  
Keyword(s):  
Liver Tissue ◽  
Tumor Volume ◽  
Major Hepatectomy ◽  
Liver Volume ◽  
Whole Body ◽  
Urea Synthesis ◽  
Arterial Blood ◽  
Before And After ◽  
Complete Adaptation ◽  
Functional Liver Volume

Changes in hepatic ureagenesis following major hepatectomy are not well characterized. We studied the relation between urea synthesis and liver mass before and after major hepatectomy in humans. Fifteen patients scheduled for resection of malignancies in otherwise healthy livers were studied. Pre- and postoperative liver volume was assessed by computerized tomography-volumetry. During surgery, a primed, continuous infusion of [13C]urea was administered intravenously, and arterial blood samples were obtained hourly. Indocyanine green clearance was determined before and after resection. Seven patients underwent major hepatectomy, and eight patients underwent minor [<5% functional liver volume (total volume − tumor volume)] or no resection, serving as controls. Resected functional liver volume in the major hepatectomy group averaged 60%. Urea synthesis per gram of functional liver tissue increased 2.6-fold following major hepatectomy, maintaining whole body urea synthesis. Arterial ammonia remained unchanged throughout the study, whereas following hepatectomy a hyperaminoacidemia occurred. In conclusion, immediately following major hepatectomy, urea synthesis per gram of functional liver tissue increases rapidly and proportionately to the amount of liver tissue resected, maintaining whole body urea synthesis at preoperative levels. This rapid and complete adaptation suggests that the capacity of urea synthesis is not limiting the maximum resectable volume in otherwise healthy livers.

scholarly journals De Novo Endotoxin-Induced Production of Antibodies against the Bile Salt Export Pump Associated with Bacterial Infection following Major Hepatectomy

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Kun-Ming Chan ◽  
Chih-Hsien Cheng ◽  
Tsung-Han Wu ◽  
Chen-Fang Lee ◽  
Ting-Jung Wu ◽  
...  
Keyword(s):  
Bacterial Infection ◽  
Bile Salt ◽  
Liver Tissue ◽  
De Novo ◽  
Major Hepatectomy ◽  
Liver Volume ◽  
Severe Infection ◽  
High Dose ◽  
Bile Salt Export Pump ◽  
The Impact

Background. Clinically severe infection-related inflammation after major liver resection may cause hyperbilirubinemia. This study aims to clarify the impact of bacterial infection and endotoxins on the hepatobiliary transporter system and to explore possible mechanisms of endotoxin-related postoperative hyperbilirubinemia.Method. Mice that underwent major hepatectomy with removal of at least 70% of liver volume were exposed to lipopolysaccharide (LPS) at different dosages. Subsequently, hepatobiliary transporter compounds related to bile salt excretion were further investigated.Results. The expression of genes related to hepatobiliary transporter compounds was not significantly different in the liver tissue of mice after major hepatectomy and LPS exposure. However, bile salt export pump (BSEP) protein expression within the liver tissue of mice treated with LPS after major hepatectomy was relatively weaker and was even further reduced in the high-dose LPS group. The formation of antibodies against the BSEP in response to endotoxin exposure was also detected.Conclusion. This study illustrates a possible mechanism whereby the dysfunction of hepatobiliary transporter systems caused by endotoxin-induced autoantibodies may be involved in the development of postoperative jaundice associated with bacterial infection after major hepatectomy.

Effects of cold exposure and exercise in a wet, cold antarctic climate

1965 ◽  
Vol 20 (3) ◽  
pp. 417-422 ◽  
Author(s):  
G. M. Budd
Keyword(s):  
Physical Fitness ◽  
Cold Exposure ◽  
Subcutaneous Fat ◽  
Whole Body ◽  
Finger Temperature ◽  
Arterial Blood ◽  
Before And After ◽  
Tissue Insulation ◽  
Body Cooling ◽  
Whole Body Cooling

Six men were studied before and after 6 weeks of strenuous outdoor work and cold exposure—often in wet clothing—on Heard Island in the Antarctic. Physical fitness increased significantly, while subcutaneous fat and arterial blood pressure decreased significantly. The response of rectal temperature and shivering to a 2-hr period of whole-body cooling did not change significantly (although shivering tended to decrease), suggesting that the reduction in insulation caused by loss of fat was balanced by an increase in the insulation of other tissues. Finger temperature fell more rapidly, there was less cold vasodilatation, and the gradient of skin temperature between elbow and finger increased significantly, suggesting that heat was conserved by means of countercurrent heat exchanges and enhanced vasoconstriction. Discomfort from cold did not change. These results support those of a previous study at Mawson, Antarctica. Frostbite of one subject's hands, which grossly impaired touch sensation and caused marked intolerance to cold, produced no obvious changes in the response to cold of finger temperature. vasomotor adaptation to cold; cold vasodilatation; tissue insulation; subcutaneous fat; shivering; subjective responses to cold; frostbite sequelae; finger temperature before and after cold injury; physical fitness; acclimatization to cold Submitted on September 8, 1964

Influence of aging on tissue-specific noradrenergic activity at rest and during nonexertional heating in rats

1994 ◽  
Vol 76 (3) ◽  
pp. 1226-1231 ◽  
Author(s):  
K. C. Kregel
Keyword(s):  
Renal Cortex ◽  
Age Groups ◽  
Whole Body ◽  
Turnover Rates ◽  
Internal Organs ◽  
Fischer 344 ◽  
Arterial Blood ◽  
Before And After ◽  
Temperature Levels ◽  
Colonic Temperature

The purpose of this study was to test the hypothesis that sympathetic nervous system (SNS) activity to internal organs during nonexertional heat stress is exaggerated with advancing age. Norepinephrine (NE) synthesis was blocked with alpha-methyl-DL-p-tyrosine, and NE turnover rates were determined in the left ventricle, renal cortex, liver, and adrenal gland in groups of conscious unrestrained mature (12-mo-old) and senescent (24-mo-old) Fischer 344 rats before and after whole body heating. Animals were maintained in thermoneutral control conditions (n = 10 per group) or exposed to an ambient temperature of 42 degrees C until colonic temperature (TCO) reached a designated level (39.5 or 41.0 degrees C; n = 10 per group at both temperature levels). NE turnover rates were similar in all four tissues sampled for both mature and senescent rats in the resting condition. Over the course of the heating period, progressive increases in arterial blood pressure and heart rate were observed, with the magnitudes of the pressor and tachycardic responses similar between age groups. At TCO of 39.5 degrees C, calculated NE turnover rates were unchanged from control levels for the senescent and mature animals, whereas animals heated to 41.0 degrees C demonstrated marked elevations in NE turnover in all four tissues for both age groups. In addition, the increase in NE turnover rate at this TCO was significantly higher for senescent rats compared with their younger counterparts in the renal cortex (410 vs. 278%) and liver (557 vs. 170%).(ABSTRACT TRUNCATED AT 250 WORDS)

Artifact removal from neurophysiological signals: impact on intracranial and arterial pressure monitoring in traumatic brain injury

2020 ◽  
Vol 132 (6) ◽  
pp. 1952-1960 ◽  
Author(s):  
Seung-Bo Lee ◽  
Hakseung Kim ◽  
Young-Tak Kim ◽  
Frederick A. Zeiler ◽  
Peter Smielewski ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Neurological Status ◽  
Cerebrovascular Reactivity ◽  
Cerebral Hypoperfusion ◽  
Clinical Parameters ◽  
Artifact Removal ◽  
Clinical Events ◽  
Arterial Blood ◽  
Before And After

OBJECTIVEMonitoring intracranial and arterial blood pressure (ICP and ABP, respectively) provides crucial information regarding the neurological status of patients with traumatic brain injury (TBI). However, these signals are often heavily affected by artifacts, which may significantly reduce the reliability of the clinical determinations derived from the signals. The goal of this work was to eliminate signal artifacts from continuous ICP and ABP monitoring via deep learning techniques and to assess the changes in the prognostic capacities of clinical parameters after artifact elimination.METHODSThe first 24 hours of monitoring ICP and ABP in a total of 309 patients with TBI was retrospectively analyzed. An artifact elimination model for ICP and ABP was constructed via a stacked convolutional autoencoder (SCAE) and convolutional neural network (CNN) with 10-fold cross-validation tests. The prevalence and prognostic capacity of ICP- and ABP-related clinical events were compared before and after artifact elimination.RESULTSThe proposed SCAE-CNN model exhibited reliable accuracy in eliminating ABP and ICP artifacts (net prediction rates of 97% and 94%, respectively). The prevalence of ICP- and ABP-related clinical events (i.e., systemic hypotension, intracranial hypertension, cerebral hypoperfusion, and poor cerebrovascular reactivity) all decreased significantly after artifact removal.CONCLUSIONSThe SCAE-CNN model can be reliably used to eliminate artifacts, which significantly improves the reliability and efficacy of ICP- and ABP-derived clinical parameters for prognostic determinations after TBI.

scholarly journals Response in Growth, Scute Development, and Whole-Body Ion Composition of Acipenser fulvescens Reared in Water of Differing Chemistries

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1419
Author(s):  
Janet Genz ◽  
Rachael Hicks
Keyword(s):  
River Water ◽  
Growth And Development ◽  
Lake Sturgeon ◽  
Whole Body ◽  
Acipenser Fulvescens ◽  
Water Type ◽  
Ion Composition ◽  
Ion Concentrations ◽  
Before And After ◽  
Yolk Absorption

In fishes, environmental ion availability can have substantial effects on growth and development. This study examined the development of Lake Sturgeon in response to the varying environmental ion availability that they experience as part of a conservation stocking program. We reared sturgeon in natural water from the Coosa River, which had higher concentrations of Mg2+, Na+, and Zn2+ than standard hatchery conditions, while [Ca2+] at the Warm Springs National Fish Hatchery was 2× higher than in the Coosa River. Eggs were hatched in each water type and the larvae were sampled at time points before and after yolk absorption during the first 8 weeks of development. Total length and weight in WSNFH larvae were significantly higher than larvae in Coosa River water starting at 8 dph, indicating that growth was dependent on the different environmental ion levels. Concentrations of the ions of interest were also determined for whole-body acid digests of the exposed Lake Sturgeon. We found that Lake Sturgeon reared in Coosa River water had significantly higher magnesium and zinc than Lake Sturgeon reared in WSNFH water (p < 0.05), while calcium was significantly higher in WSNFH than Coosa River water. This difference shows that different environmental ion concentrations also impact the overall development of larval Lake Sturgeon.

The effect of mask use on maternal oxygen saturation in term pregnancies during the COVID-19 process

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Erzat Toprak ◽  
Ayça Nazlı Bulut
Keyword(s):  
Oxygen Saturation ◽  
Pregnant Women ◽  
Stress Test ◽  
Statistical Significance ◽  
Categorical Variables ◽  
Fisher Exact Test ◽  
Coin Toss ◽  
Arterial Blood ◽  
Surgical Masks ◽  
Before And After

AbstractObjectivesOur aim was to evaluate the effect of standard surgical and N-95 respiratory mask use on maternal oxygen saturation, vital signs and result on non-stress tests in term pregnancies.MethodsIt is a prospective observational study. The study included healthy, not in labor, singleton pregnant women of 370/7–410/7 weeks who were applied to our hospital for routine obstetric control examination between March 1, 2020, and August 31, 2020. Patients were randomised by coin toss method. Oxygen saturation, systolic, and diastolic arterial blood pressure, pulse, respiratory rate, and temperature of pregnant women using surgical masks and respiratory masks were measured before and after the non-stress test. The tolerance of the masks was also evaluated. Student’s t-test was used for variables showing parametric distribution and the Mann Whitney U-test was used for non-parametric tests. The categorical variables between the groups was analyzed by using the Chi square test or Fisher Exact test. The statistical significance level was taken as p<0.05 in all tests.ResultsA total of 297 pregnant women using masks were included in the study. The effect of mask type on oxygen saturation before and after the non-stress test was found to be significant (97.1±1.8 corresponds to 95.3±2.6 for the surgical mask, p=0.0001; 97.8±1.7 corresponds to 93.7±2.0 for the respiratory mask, p=0.0001). Mask tolerance of patients using respiratory masks was significantly higher than those using surgical masks (mean 8, 1–10, p=0.0001).ConclusionsSurgical mask and respiratory mask usage decreased significantly in oxygen saturation in term pregnancies.

Antitumor effects of Auraptene in 4T1 tumor‐bearing Balb/c mice

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohammad Reza. Shiran ◽  
Davar Amani ◽  
Abolghasem Ajami ◽  
Mahshad Jalalpourroodsari ◽  
Maghsoud Khalizadeh ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Body Weight ◽  
Tumor Volume ◽  
Serum Levels ◽  
Ki 67 ◽  
Tumor Bearing ◽  
Paraffin Oil ◽  
Anti Cancer ◽  
Before And After ◽  
Ifn Γ

Abstract Objectives Breast cancer is a common malignant tumor in women with limited treatment options and multiple side effects. Today, the anti-cancer properties of natural compounds have attracted widespread attention from researchers worldwide. Methods In this study, we treated 4T1 tumor-bearing Balb/c mice with intraperitoneal injection of Auraptene, paraffin oil, and saline as two control groups. Body weight and tumor volume were measured before and after treatment. Hematoxylin and eosin (H & E) staining and immunohistochemistry of Ki-67 were used as markers of proliferation. In addition, ELISA assays were performed to assess serum IFN-γ and IL-4 levels. Results There was no significant change in body weight in all animal groups before and after treatment. 10 days after the last treatment, Auraptene showed its anti-cancer effect, which was confirmed by the smaller tumor volume and H & E staining. In addition, Ki-67 expression levels were significantly reduced in tumor samples from the Auraptene-treated group compared to the paraffin oil and saline-treated groups. In addition, in tumor-bearing and normal mice receiving Auraptene treatment, IL-4 serum production levels were reduced, while serum levels of IFN-γ were significantly up-regulated in tumor-bearing mice after Auraptene treatment. Conclusions In the case of inhibition of tumor volume and Ki-67 proliferation markers, Auraptene can effectively inhibit tumor growth in breast cancer animal models. In addition, it might increases Th1 and CD8 + T cell responses after reducing IL-4 serum levels and IFN-γ upregulation, respectively. However, further research is needed to clarify its mechanism of action.

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