The consumption of viruses returns energy to food chains.

Viruses impact host cells and have indirect effects on ecosystem processes. Plankton such as ciliates can reduce the abundance of virions in water, but whether virus consumption translates into demographic consequences for the grazers is unknown. Here, we show that small protists not only can consume viruses they also can grow and divide given only viruses to eat. Moreover, the ciliate Halteria sp. foraging on chloroviruses displays dynamics and interaction parameters that are similar to other microbial trophic interactions. These results suggest that the effect of viruses on ecosystems extends beyond (and in contrast to) the viral shunt by redirecting energy up food chains.

Utility of cortical tissue analysis in normal pressure hydrocephalus.

Clinical improvement following neurosurgical cerebrospinal fluid shunting for presumed idiopathic normal pressure hydrocephalus is variable. Idiopathic normal pressure hydrocephalus patients may have undetected Alzheimer's disease-related cortical pathology that confounds diagnosis and clinical outcomes. In this study, we sought to determine the utility of cortical tissue immuno-analysis in predicting shunting outcomes in idiopathic normal pressure hydrocephalus patients. We performed a pooled analysis using a systematic review as well as analysis of a new, original patient cohort. Of the 2707 screened studies, 3 studies with a total of 229 idiopathic normal pressure hydrocephalus patients were selected for inclusion in this meta-analysis alongside our original cohort. Pooled statistics of shunting outcomes for the 229 idiopathic normal pressure hydrocephalus patients and our new cohort of 36 idiopathic normal pressure hydrocephalus patients revealed that patients with Aß + pathology were significantly more likely to exhibit shunt nonresponsiveness than patients with negative pathology. Idiopathic normal pressure hydrocephalus patients with Alzheimer's disease -related cortical pathology may be at a higher risk of treatment facing unfavorable outcomes following cerebrospinal fluid shunting. Thus, cortical tissue analysis from living patients may be a useful diagnostic and prognostic adjunct for patients with presumed idiopathic normal pressure hydrocephalus and potentially other neurodegenerative conditions affecting the cerebral cortex.

Antigen titers in cryptococcal meningitis: what determines how fast they fall?

Follow-up of previously healthy patients surviving cryptococcal meningitis found that cryptococcal antigen could be detected for more than one year in serum from 38 of 44 (86%) patients and in CSF from 20 of 31 patients (67%), far beyond the time of culture conversion. The speed of titer decline, measured as the number of days for a two fold drop in titer to occur, was slower in serum than in CSF. Speed of decline of antigen titers was much slower in serum and CSF for patients infected with C. gattii than C. neoformans. The speed of decline in CSF and serum titers was also much slower in patients who had received a ventriculoperitoneal shunt for increased intracranial pressure. The variable and extraordinarily slow rate of clearance in our patients did not appear to reflect differences in disease control but rather differences in species and shunting for increased intracranial pressure.

Cardiopulmonary haemodynamics in Tibetans and Han Chinese during rest and exercise.

During sea-level exercise, blood flow through intrapulmonary arteriovenous anastomoses (IPAVA) in humans without a patent foramen ovale (PFO) is negatively correlated with pulmonary pressure. Yet, it is unknown whether the superior exercise capacity of Tibetans well adapted to living at high altitude is the result of lower pulmonary pressure during exercise in hypoxia, and whether their cardiopulmonary characteristics are significantly different from lowland natives of comparable ancestry (e.g. Han Chinese). We found a 47% PFO prevalence in male Tibetans (n = 19) and Han Chinese (n = 19) participants. In participants without a PFO (n = 10 each group), we measured heart structure and function at rest and peak oxygen uptake ( V ̇ O 2 peak ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{peak}}}}$ ), peak power output ( W ̇ p e a k ${{\dot{W}}_{peak}}$ ), pulmonary artery systolic pressure (PASP), blood flow through IPAVA and cardiac output ( Q ̇ T ${{\dot{Q}}_{\mathrm{T}}} $ ) at rest and during recumbent cycle ergometer exercise at 760 Torr (SL) and at 410 Torr (ALT) barometric pressure in a pressure chamber. Tibetans achieved a higher W peak ${W}_{\textit{peak}}$ than Han, and a higher V ̇ O 2 peak ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{peak}}}}$ at ALT without differences in heart rate, stroke volume or Q ̇ T ${{\dot{Q}}_{\mathrm{T}}} $ . Blood flow through IPAVA was generally similar between groups. Increases in PASP and total pulmonary resistance at ALT were comparable between the groups. There were no differences in the slopes of PASP plotted as a function of Q ̇ T ${{\dot{Q}}_{\mathrm{T}}} $ during exercise. In those without PFO, our data indicate that the superior aerobic exercise capacity of Tibetans over Han Chinese is independent of cardiopulmonary features and more probably linked to differences in local muscular oxygen extraction. KEY POINTS: Patent foramen ovale (PFO) prevalence was 47% in Tibetans and Han Chinese living at 2 275 m. Subjects with PFO were excluded from exercise studies. Compared to Han Chinese, Tibetans had a higher peak workload with acute compression to sea level barometric pressure (SL) and acute decompression to 5000 m altitude (ALT). Comprehensive cardiac structure and function at rest were not significantly different between Han Chinese and Tibetans. Tibetans and Han had similar blood flow through intrapulmonary arteriovenous anastomoses (IPAVA) during exercise at SL. Peak pulmonary artery systolic pressure (PASP) and total pulmonary resistance were different between SL and ALT, with significantly increased PASP for Han compared to Tibetans at ALT. No differences were observed between groups at acute SL and ALT.

Identifying the optimal measurement timing and hemodynamic targets of portal pressure gradient after TIPS in patients with cirrhosis and variceal bleeding: a prospective cohort study.

BACKGROUND & AIMS: The optimal timing of measurement and hemodynamic targets of portacaval pressure gradient (PPG) after TIPS remains inconclusive. This study aimed to identify the ideal moment of hemodynamic measurements and the optimal target of PPG in patients undergoing covered TIPS for variceal bleeding. METHODS: Between May 2018 and December 2021, 466 consecutive patients with recurrent variceal bleeding treated with covered TIPS were prospectively included. Post-TIPS PPG were measured immediately (immediate PPG), 24-72 hours (early PPG), and again 1 month (late PPG) after TIPS placement. The agreement among PPGs measured at different time points was assessed by intra-class correlation coefficient (ICC) and Bland-Altman method. The unadjusted and confounder-adjusted effects of PPGs on the clinical outcomes (portal hypertension complications [PHC], overt hepatic encephalopathy [OHE], further decompensation, and death) were assessed using Fine and Gray competing risk regression models. RESULTS: The agreement between early PPG and late PPG (ICC: 0.34) was better than that between immediate PPG and late PPG (ICC: 0.23, p<0.001). Early PPG revealed an excellent predictive value for PHC risk (early PPG ≥ vs <12 mmHg: adjusted HR [95%CI]: 2.17 [1.33-3.55], p=0.002) as well as OHE (0.40 [0.17-0.91], p=0.030) while immediate PPG did not. Late PPG showed a predictive value for PHC risk but not OHE. By targeting the lowest risk of further decompensation, we identified an optimal hemodynamic target with early PPG ranging 11 to 14 mmHg that was associated with a decreased risk of OHE while effectively preventing PHC. CONCLUSIONS: PPG measured 24 to 72 hours after TIPS correlates with long term PPG and clinical outcomes, and hemodynamic target with a PPG 11-14 mmHg reduced encephalopathy but not compromised clinical efficacy. IMPACT AND IMPLICATIONS: The optimal timing of measurement and hemodynamic targets of portacaval pressure gradient (PPG) after transjugular intrahepatic portosystemic shunt (TIPS) remains inconclusive. Here we show that post-TIPS PPG measured at least 24 hours but not immediately after the procedure correlated with long-term PPG and clinical events, therefore should be used for decision making in order to improve clinical outcomes. Targeting post-TIPS PPG at 11-14 mmHg or 20%-50% relative reduction from pre-TIPS baseline that measured 24-72 hours after procedure reduced encephalopathy but not compromised clinical efficacy, therefore could be used to guide TIPS creation and revision in patients with cirrhosis and variceal bleeding undergoing covered TIPS. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov, ID: NCT03590288.

High Prevalence and Clinical Relevance of Intrapulmonary Vascular Dilatations in Patients Undergoing TIPS Implantation.

BACKGROUND & AIMS: Considerate patient selection is vital to ensure the best possible outcomes after transjugular intrahepatic portosystemic shunt (TIPS) insertion. However, data regarding the impact of intrapulmonary vascular dilatations (IPVDs) or hepatopulmonary syndrome (HPS) on the clinical course after TIPS implantation is lacking. Hence, this study aimed to investigate the relevance of IPVD and HPS in patients undergoing TIPS implantation. METHODS: Contrast enhanced echocardiography and blood gas analysis were utilized to determine presence of IPVD and HPS. Multivariable competing risk analyses were performed to evaluate cardiac decompensation (CD), hepatic decompensation (HD), and liver transplant (LTx)-free survival within 1 year of follow-up. RESULTS: Overall, 265 patients were included, of whom 136 had IPVD and 71 fulfilled the HPS criteria. Patients with IPVD had lower Freiburg index of post-TIPS survival (FIPS) scores, lower creatinine, and more often received TIPS because of variceal bleeding. Presence of IPVD was associated with a significantly higher incidence of CD (hazard ratio [HR], 1.756; 95% confidence interval [CI], 1.011-3.048; P = .046) and HD (HR, 1.841; 95% CI, 1.255-2.701; P = .002). However, LTx-free survival was comparable between patients with and without IPVD (HR, 1.081; 95% CI, 0.630-1.855; P = .780). Patients with HPS displayed a trend towards more CD (HR, 1.708; 95% CI, 0.935-3.122; P = .082) and HD (HR, 1.458; 95% CI, 0.934-2.275; P = .097) that failed to reach statistical significance. LTx-free survival did not differ in those with HPS compared with patients without HPS, respectively (HR, 1.052; 95% CI, 0.577-1.921; P = .870). CONCLUSION: Screening for IPVD before TIPS implantation could help to further identify patients at higher risk of CD and HD.

Lessons from Chloroviruses: the Complex and Diverse Roles of Viruses in Food Webs.

Viruses can have large effects on the ecological communities in which they occur. Much of this impact comes from the mortality of host cells, which simultaneously alters microbial community composition and causes the release of matter that can be used by other organisms. However, recent studies indicate that viruses may be even more deeply integrated into the functioning of ecological communities than their effect on nutrient cycling suggests. In particular, chloroviruses, which infect chlorella-like green algae that typically occur as endosymbionts, participate in three types of interactions with other species. Chlororviruses (i) can lure ciliates from a distance, using them as a vector; (ii) depend on predators for access to their hosts; and (iii) get consumed as a food source by, at least, a variety of protists. Therefore, chloroviruses both depend on and influence the spatial structures of communities as well as the flows of energy through those communities, driven by predator-prey interactions. The emergence of these interactions are an eco-evolutionary puzzle, given the interdependence of these species and the many costs and benefits that these interactions generate.

Measuring CSF shunt flow with MRI using flow enhancement of signal intensity (FENSI).

PURPOSE: To develop and validate a noninvasive imaging technique for accurately assessing very slow CSF flow within shunt tubes in pediatric patients with hydrocephalus, aiming to identify obstructions that might impede CSF drainage. THEORY AND METHODS: A simulation of shunt flow enhancement of signal intensity (shunt-FENSI) signal is used to establish the relationship between signal change and flow rate. The quantification of flow enhancement of signal intensity data involves normalization, curve fitting, and calibration to match simulated data. Additionally, a phase sweep method is introduced to accommodate the impact of magnetic field inhomogeneity on the flow measurement. The method is tested in flow phantoms, healthy adults, intensive care unit patients with external ventricular drains (EVD), and shunt patients. EVDs enable shunt-flow measurements to be acquired with a ground truth measure of CSF drainage. RESULTS: The flow-rate-to-signal simulation establishes signal-flow relationships and takes into account the T1 of draining fluid. The phase sweep method accurately accounts for phase accumulation due to frequency offsets at the shunt. Results in phantom and healthy human participants reveal reliable quantification of flow rates using controlled flows and agreement with the flow simulation. EVD patients display reliable measures of flow rates. Shunt patient results demonstrate feasibility of the method and consistent flow rates for functional shunts. CONCLUSION: The results demonstrate the technique's applicability, accuracy, and potential for diagnosing and noninvasively monitoring hydrocephalus. Limitations of the current approach include a high sensitivity to motion and strict requirement of imaging slice prescription.

Elucidation of triacylglycerol catabolism in Yarrowia lipolytica: How cells balance acetyl-CoA and excess reducing equivalents.

Yarrowia lipolytica is an industrial yeast that can convert waste oil to value-added products. However, it is unclear how this yeast metabolizes lipid feedstocks, specifically triacylglycerol (TAG) substrates. This study used 13C-metabolic flux analysis (13C-MFA), genome-scale modeling, and transcriptomics analyses to investigate Y. lipolytica W29 growth with oleic acid, glycerol, and glucose. Transcriptomics data were used to guide 13C-MFA model construction and to validate the 13C-MFA results. The 13C-MFA data were then used to constrain a genome-scale model (GSM), which predicted Y. lipolytica fluxes, cofactor balance, and theoretical yields of terpene products. The three data sources provided new insights into cellular regulation during catabolism of glycerol and fatty acid components of TAG substrates, and how their consumption routes differ from glucose catabolism. We found that (1) over 80% of acetyl-CoA from oleic acid is processed through the glyoxylate shunt, a pathway that generates less CO2 compared to the TCA cycle, (2) the carnitine shuttle is a key regulator of the cytosolic acetyl-CoA pool in oleic acid and glycerol cultures, (3) the oxidative pentose phosphate pathway and mannitol cycle are key routes for NADPH generation, (4) the mannitol cycle and alternative oxidase activity help balance excess NADH generated from ß-oxidation of oleic acid, and (5) asymmetrical gene expressions and GSM simulations of enzyme usage suggest an increased metabolic burden for oleic acid catabolism.

Assessment of Ventricular Size and Neurocognitive Outcomes in Children with Postnatal Closure of Myelomeningocele.

OBJECTIVE: To assess if ventricular size before shunting is correlated with neurodevelopmental outcomes in children with postnatal myelomeningocele closure. STUDY DESIGN: This retrospective review included children with postnatal surgical closure of myelomeningocele and neuropsychological testing between 2018 and 2023 at the University of California, San Francisco. Frontal-occipital horn ratio (FOHR) was measured immediately before shunt placement or on the first study that reported ventricular stability for nonshunted patients. The primary outcome was full scale IQ (FSIQ) on the Weschler Intelligence Scale. Secondary outcomes included indices of the Weschler scale, the Global Executive Composite from the Behavior Rating Inventory of Executive Function, and the general adaptive composite from the Adaptive Behavior Assessment Scale. Univariable and multivariable regression was used to determine if FOHR was correlated with neuropsychological scores. RESULTS: Forty patients met the inclusion criteria; 26 (65%) had shunted hydrocephalus. Age at neuropsychological testing was 10.9 ± 0.6 years. FOHR was greater in the shunted group (0.64 vs 0.51; P < .001). There were no differences in neuropsychological results between shunted and nonshunted groups. On univariable analysis, greater FOHR was associated with lower FSIQ (P = .025) and lower Visual Spatial Index scores (P = .013), which remained significant on multivariable analysis after adjusting for gestational age at birth, lesion level, shunt status, and shunt revision status (P = .049 and P = .006, respectively). Separate analyses by shunt status revealed that these effects were driven by the shunted group. CONCLUSIONS: Greater FOHR before shunting was correlated with lower FSIQ and the Visual Spatial Index scores on the Weschler Intelligence Scales. Larger studies are needed to explore further the relationship between ventricle size, hydrocephalus, and neurodevelopmental outcomes.

Aqueous Shunts with Extraocular Reservoir for Open-Angle Adult Glaucoma: A Report by the American Academy of Ophthalmology.

PURPOSE: To evaluate the recently published literature on the efficacy and safety of the use of aqueous shunts with extraocular reservoir for the management of adult open-angle glaucomas (OAGs). METHODS: A search of peer-reviewed literature was last conducted in April 2023 of the PubMed database and included only articles published since the last aqueous shunt Ophthalmic Technology Assessment, which assessed articles published before 2008. The abstracts of these 419 articles were examined, and 58 studies were selected for full-text analysis. After inclusion and exclusion criteria were applied, 28 articles were selected and assigned ratings by the panel methodologist according to the level of evidence. Twenty-five articles were rated level I and 3 articles were rated level II. There were no level III articles. RESULTS: Implantation of aqueous shunts with extraocular reservoir can lower intraocular pressure (IOP) by between one-third and one-half of baseline IOP, depending on whether it is undertaken as the primary or secondary glaucoma surgery. Success rates for aqueous shunts were found to be better than for trabeculectomies in eyes with prior incisional surgery. Conversely, in eyes without prior incisional surgery, implantation of aqueous shunts was found to have an overall lower success rate as the primary glaucoma procedure compared with trabeculectomy. Although both valved and nonvalved aqueous shunts with extraocular reservoir were effective, the nonvalved device generally achieved slightly lower long-term IOPs with fewer glaucoma medications and less need for additional glaucoma surgery. Both devices slow the rates of visual field progression with efficacy comparable with that of trabeculectomy. Early aqueous humor suppression after aqueous shunt implantation is recommended for the management of the postoperative hypertensive phase and long-term IOP control. No strong evidence supports the routine use of mitomycin C with aqueous shunt implantation for OAG. CONCLUSIONS: Implantation of aqueous shunts with extraocular reservoir, including valved or nonvalved devices, has been shown to be an effective strategy to lower IOP. Strong level I evidence supports the use of aqueous shunts with extraocular reservoir by clinicians for the management of adult OAG. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Visual Field Outcomes in the Primary Tube Versus Trabeculectomy Study.

PURPOSE: To describe visual field outcomes in the Primary Tube Versus Trabeculectomy (PTVT) Study. DESIGN: Cohort analysis. PARTICIPANTS: A total of 155 eyes (155 subjects) randomly assigned to treatment with tube shunt surgery (n = 84) or trabeculectomy with mitomycin C (n = 71). METHODS: The PTVT Study was a multicenter randomized clinical trial comparing the safety and efficacy of trabeculectomy and tube shunt surgery in eyes without previous intraocular surgery. Subjects underwent standard automated perimetry (SAP) at baseline and annually for 5 years. Standard automated perimetry tests were deemed reliable if the false-positive rate was ≤ 15%. Tests were excluded if visual acuity was ≤ 20/400 or loss of ≥ 2 Snellen lines from baseline because of a nonglaucomatous etiology. Linear mixed-effects models were used to compare rates of change in SAP mean deviation (MD) between the 2 groups. Intraocular pressure (IOP) control was assessed by percentage of visits with IOP < 18 mmHg and mean IOP. MAIN OUTCOME MEASURES: Rate of change in SAP MD during follow-up. RESULTS: A total of 730 SAP tests were evaluated (average of 4.7 tests per eye). The average SAP MD at baseline was -12.8 ± 8.3 decibels (dB) in the tube group and -12.0 ± 8.4 dB in the trabeculectomy group (P = 0.57). The mean rate of change in SAP MD was -0.32 ± 0.39 dB/year in the trabeculectomy group and -0.47 ± 0.43 dB/year in the tube group (P = 0.23). Eyes with mean IOP 14 to 17.5 mmHg had significantly faster rates of SAP MD loss compared with eyes with mean IOP < 14 mmHg (-0.59 ± 0.13 vs. -0.27 ± 0.08 dB/year; P = 0.012), and eyes with only 50% to 75% of visits with IOP < 18 mmHg had faster rates than those with 100% of visits with IOP < 18 mmHg (-0.90 ± 0.16 vs. -0.29 ± 0.08 dB/year; P < 0.001). Multivariable analysis identified older age and worse IOP control as risk factors for faster progression in both treatment groups. CONCLUSIONS: No statistically significant difference in mean rates of visual field change was observed between trabeculectomy and tube shunt surgery in the PTVT Study. Worse IOP control was significantly associated with faster rates of SAP MD loss during follow-up. Older patients were also at risk for faster progression.

A device-related fistula between coronary artery and left atrial appendage following left atrial appendage closure: Case presentation.

INTRODUCTION: Left atrial appendage (LAA) closure (LAAC) is considered a viable alternative to anticoagulation therapy for stroke prevention in nonvalvular atrial fibrillation, we report a case with a less common shunt resulting from a device-related coronary artery-appendage fistula (CAAF) following LAAC. METHODS AND RESULTS: A 67-year-old male with a history of LAAC was referred to our emergency room with recurrent chest pain and palpitations and was diagnosed with ischemic angina pectoris. Subsequent coronary angiography (CAG) revealed 70% in-stent restenosis and an abnormal shunt of contrast originating from the left circumflex artery (LCA) to the LAA tip which did not exist before. The restenosis was successfully dilated using a drug-coated balloon, the procedure was safely completed without pericardial effusion. The patient had been implanted with a LAmbre occluder (Lifetech Scientific Corp.) in the previous LAAC procedure. This occluder had a lobe-disk design, and the distal umbrella was not fully opened after release, particularly in the lower portion. This could make the hooks embedded on the umbrella contact the LAA wall more tightly, possibly resulting in microperforation and coincidental impingement of the LCA. The epicardial adipose and hyperplastic tissue then chronically wrapped the perforated site, prevented blood outflow into the epicardium, and ultimately formed a CAAF. CONCLUSION: CAAF is a rare complication after LAAC but may be underestimated, especially for lobe-disk designed occluders. Therefore, CAG is perhaps necessary to detect this complication.

Outcomes of Rehabilitation Strategies for Pulmonary Atresia with Ventricular Septal Defect: A Single Center's Experience.

Background: Both systemic-to-pulmonary shunt and right ventricle-pulmonary artery (RV-PA) connection are extensively applied to initially rehabilitate the pulmonary artery in pulmonary atresia with the ventricle septal defect (PA/VSD). However, which of these options is the most ideal for promoting pulmonary artery development and improving outcomes remains controversial. Methods: A total of 109 PA/VSD patients undergoing initial rehabilitative surgery at Guangdong Provincial People's Hospital from 2010 to 2020 were enrolled in this study. A series of clinical data were collected to compare the perioperative and postoperative outcomes between systemic-to-pulmonary and RV-PA connection. Results: The mean duration of follow-up was 61.1 months in the systemic-to-pulmonary shunt group and 70.3 months in the RV-PA connection group (p > 0.05). The RV-PA connection technique resulted in a significantly higher PaO 2 , lower red blood cells (RBC), lower hemoglobin, and lower hematocrit (Hct) (p < 0.05). The cumulative incidence curve estimated a cumulative complete repair rate of 56 ± 7% after 5 years in the RV-PA connection group, significantly higher than 36 ± 7% after 5 years in the systemic-to-pulmonary shunt group (p < 0.05). The Kaplan-Meier curve revealed a similar estimated survival rate between the two groups (p = 0.73). The RV-PA connection was identified as an independent predictor for complete repair in the multivariable analysis (HR = 2.348, 95% CI = 1.131-4.873). Conclusions: The RV-PA connection is a more ideal initial rehabilitative technique than systemic-to-pulmonary shunt in treating PA/VSD as a consequence of comparable probability of survival but improved definitive complete repair rate.

Does depressurization of the portal vein before liver transplantation affect the recurrence of HCC? A nested case-control study.

BACKGROUND: Portal hypertension (PHT) has been proven to be closely related to the development of hepatocellular carcinoma (HCC). Whether PHT before liver transplantation (LT) will affect the recurrence of HCC is not clear. METHODS: 110 patients with depressurization of the portal vein (DPV) operations (Transjugular Intrahepatic Portosystemic Shunt-TIPS, surgical portosystemic shunt or/and splenectomy) before LT from a HCC LT cohort, matched with 330 preoperative non-DPV patients; this constituted a nested case-control study. Subgroup analysis was based on the order of DPV before or after the occurrence of HCC. RESULTS: The incidence of acute kidney injury and intra-abdominal bleeding after LT in the DPV group was significantly higher than that in non-DPV group. The 5-year survival rates in the DPV and non-DPV group were 83.4% and 82.7% respectively (P = 0.930). In subgroup analysis, patients in the DPV prior to HCC subgroup may have a lower recurrence rate (4.7% vs.16.8%, P = 0.045) and a higher tumor free survival rate (88.9% vs.74.4%, P = 0.044) after LT under the up-to-date TNMI-II stage, while in TNM III stage, there was no difference for DPV prior to HCC subgroup compared with the DPV after HCC subgroup or the non-DPV group. CONCLUSION: Compared with DPV after HCC, DPV treatment before HCC can reduce the recurrence rate of HCC after early transplantation (TNM I-II). DPV before LT can reduce the recurrence of early HCC.

Endoleak in covered CP stent causes procedural failure during transcatheter closure of sinus venosus defects.

Transcatheter sinus venosus defect closure uses a long covered stent of appropriate length and diameter across the cavoatrial junction after balloon interrogation. The fabric in the covered stent creates a roof for the right upper pulmonary vein that closes the interatrial communication and redirects the vein into the left atrium behind the stent. A fabric tear in the covered stent may cause endoleak that will result in residual flows across the struts of the covered stent, causing procedural failure. This report highlights the identification of fabric leak by angiography and transesophageal echocardiography and steps to overcome this complication by the placement of another overlapping covered stent.

Nutrient limitation and oxidative stress induce the promoter of acetate operon in Salmonella Typhimurium.

Glyoxylate shunt is an important pathway for microorganisms to survive under multiple stresses. One of its enzymes, malate synthase (encoded by aceB gene), has been widely speculated for its contribution to both the pathogenesis and virulence of various microorganisms. We have previously demonstrated that malate synthase (MS) is required for the growth of Salmonella Typhimurium (S. Typhimurium) under carbon starvation and survival under oxidative stress conditions. The aceB gene is encoded by the acetate operon in S. Typhimurium. We attempted to study the activity of acetate promoter under both the starvation and oxidative stress conditions in a heterologous system. The lac promoter of the pUC19 plasmid was substituted with the putative promoter sequence of the acetate operon of S. Typhimurium upstream to the lacZ gene and transformed the vector construct into E. coli NEBα cells. The transformed cells were subjected to the stress conditions mentioned above. We observed a fourfold increase in the ß-galactosidase activity in these cells resulting from the upregulation of the lacZ gene in the stationary phase of cell growth (nutrient deprived) as compared to the mid-log phase. Following exposure of stationary phase cells to hypochlorite-induced oxidative stress, we further observed a 1.6-fold increase in ß galactosidase activity. These data suggest the induction of promoter activity of the acetate operon under carbon starvation and oxidative stress conditions. Thus, these observations corroborate our previous findings regarding the upregulation of aceB expression under stressful environments.

Recompensation after TIPS reduces the incidence of hepatocellular carcinoma and increases survival in patients with cirrhosis.

BACKGROUND AND AIMS: It has been described that recompensation can improve prognosis in patients with cirrhosis. However, recompensation after transjugular intrahepatic portosystemic shunt (TIPS) has not been studied. We evaluated the impact of recompensation after TIPS on the risk of hepatocellular carcinoma (HCC) and death, and we compared it with compensated cirrhosis patients. METHODS: An observational study of consecutive patients with cirrhosis undergoing TIPS between 2008 and 2022 was performed. Baveno VII definition of recompensation was used including patients with or without diuretics/Hepatic encephalopathy prophylaxis. A prospective cohort of consecutive compensated cirrhosis patients was used for comparison. RESULTS: Overall, 208 patients with cirrhosis were included, 92 compensated and 116 decompensated who underwent TIPS. After 1 year, 24% achieved recompensation. Liver function (MELD 12 ± 5 vs. 15 ± 6; p = .049), LDL-cholesterol (97 mg/dL vs. 76 mg/dL, p = .018), white cell count (7.96 × 109/dL vs. 6.24 × 109/dL, p = .039) and platelets (129 × 109/dL vs. 101 × 109/dL, p = .039) were associated with recompensation. Recompensation was associated with a reduction in the risk of HCC (p = .020). Multivariable analysis showed that this risk was significantly higher in non-recompensated patients (p = .003) but no differences were observed in recompensated compared with compensated patients (p = .816). Similarly, decompensated patients presented lower survival rates (p = .011), while no differences were observed between recompensated and compensated patients (p = .677). CONCLUSIONS: Recompensation after TIPS has a clear impact on the incidence of HCC and death, with a similar prognosis than patients with compensated cirrhosis. Liver function is associated with recompensation, suggesting the importance of considering early TIPS in patients with indication.

Blood oxygen transport and depletion in diving emperor penguins.

Oxygen store management underlies dive performance and is dependent on the slow heart rate and peripheral vasoconstriction of the dive response to control tissue blood flow and oxygen uptake. Prior research has revealed two major patterns of muscle myoglobin saturation profiles during dives of emperor penguins. In Type A profiles, myoglobin desaturated rapidly, consistent with minimal muscle blood flow and low tissue oxygen uptake. Type B profiles, with fluctuating and slower declines in myoglobin saturation, were consistent with variable tissue blood flow patterns and tissue oxygen uptake during dives. We examined arterial and venous blood oxygen profiles to evaluate blood oxygen extraction and found two primary patterns of venous hemoglobin desaturation that complemented corresponding myoglobin saturation profiles. Type A venous profiles had a hemoglobin saturation that (a) increased/plateaued for most of a dive's duration, (b) only declined during the latter stages of ascent, and (c) often became arterialized [arterio-venous (a-v) shunting]. In Type B venous profiles, variable but progressive hemoglobin desaturation profiles were interrupted by inflections in the profile that were consistent with fluctuating tissue blood flow and oxygen uptake. End-of-dive saturation of arterial and Type A venous hemoglobin saturation profiles were not significantly different, but did differ from those of Type B venous profiles. These findings provide further support that the dive response of emperor penguins is a spectrum of cardiac and vascular components (including a-v shunting) that are dependent on the nature and demands of a given dive and even of a given segment of a dive.

The relevance of vascular adjustments to hemodynamic control in the face of temperature change in Crotalus durissus.

The presence of cardiac shunts in ectothermic tetrapods is thought to be consistent with active vascular modulations for proper hemodynamic support. Local control of blood flow modulates tissue perfusion and thus systemic conductance (Gsys) is assumed to increase with body temperature (Tb) to accommodate higher aerobic demand. However, the general increase of Gsys presses for a higher right-to-left (R-L) shunt, which reduces arterial oxygen concentration. In contrast, Tb reduction leads to a Gsys decrease and a left-to-right shunt, which purportedly increases pulmonary perfusion and plasma filtration in the respiratory area. This investigation addressed the role of compensatory vascular adjustments in the face of the metabolic alterations caused by Tb change in the South American rattlesnake (Crotalus durissus). Cardiovascular recordings were performed in decerebrated rattlesnake preparations at 10, 20 and 30°C. The rise in Tb increased metabolic demand, and correlated with an augmentation in heart rate. Although cardiac output increased, systemic stroke volume reduced while pulmonary stroke volume remained stable. Although that resulted in a proportionally higher increase in pulmonary blood flow, the R-L shunt was maintained. While the systemic compliance of large arteries was the most relevant factor in regulating arterial systemic blood pressure, peripheral conductance of pulmonary circulation was the major factor influencing the final cardiac shunt. Such dynamic adjustment of systemic compliance and pulmonary resistance for shunt modulation has not been demonstrated before and contrasts with previous knowledge on shunt control.