Multiresidue analysis of 22 sulfonamides and their metabolites in animal tissues using quick, easy, cheap, effective, rugged, and safe extraction and high resolution mass spectrometry (hybrid linear ion trap-Orbitrap)

A new high performance liquid chromatography-high resolution mass spectrometry (HPLC-HRMS) method was developed for a simultaneous multi-residue analysis of 22 sulfonamides (SAs) and their metabolites in edible animal (pig, beef, sheep and chicken) tissues. Sample preparation was optimized on the basis of the "QuEChERS" protocol. The analytes were identified using their LC retention times and accurate mass; the identification was further confirmed by multi-stage high mass accuracy (<5ppm) mass spectrometry. The performance of the method was evaluated according to the EU guidelines for the validation of screening methods for the analysis of veterinary drugs residues. Acceptable values were obtained for: linearity (R(2)<0.99), limit of detection (LOD, 3-26μg/kg), limit of quantification (LOQ, 11-88μg/kg), accuracy (recovery 88-112%), intra- and inter-day precision 1-14 and 1-17%, respectively, decision limit (CCα) and detection capability (CCβ) around the maximum residue limits (MRL) of SAs (100μg/kg). The method was validated by analysis of a reference material FAPAS-02188 "Pig kidney" with ǀ Z-scoreǀ<0.63. The method was applied to various matrices (kidney, liver, muscle) originated from pig, beef, sheep, and chicken) allowing the simultaneous quantification of target sulfonamides at concentration levels above the MRL/2 and the identification of untargeted compounds such as N(4)-acetyl metabolites using multi-stage high mass accuracy mass spectrometry.

A Blueprint for a Synthetic Genetic Feedback Controller to Reprogram Cell Fate

To artificially reprogram cell fate, experimentalists manipulate the gene regulatory networks (GRNs) that maintain a cell's phenotype. In practice, reprogramming is often performed by constant overexpression of specific transcription factors (TFs). This process can be unreliable and inefficient. Here, we address this problem by introducing a new approach to reprogramming based on mathematical analysis. We demonstrate that reprogramming GRNs using constant overexpression may not succeed in general. Instead, we propose an alternative reprogramming strategy: a synthetic genetic feedback controller that dynamically steers the concentration of a GRN's key TFs to any desired value. The controller works by adjusting TF expression based on the discrepancy between desired and actual TF concentrations. Theory predicts that this reprogramming strategy is guaranteed to succeed, and its performance is independent of the GRN's structure and parameters, provided that feedback gain is sufficiently high. As a case study, we apply the controller to a model of induced pluripotency in stem cells.

Pharmacokinetics of FK506 in liver transplant recipients after continuous intravenous infusion

The first-dose pharmacokinetics of FK506 was studied in nine orthotopic liver transplant patients receiving continuous intravenous infusion of 0.15 mg/kg/day. Multiple blood samples were obtained during the infusion and plasma FK506 concentrations were measured by enzyme-linked immunosorbent assay. The plasma clearance ranged from 0.47 to 5.8 L/minute, and the half-life ranged from 4.5 hours to 33.1 hours. These results indicate the pharmacokinetics of FK506 to be highly variable between patients. FK506 is extensively distributed outside the plasma compartment. FK506 is extensively metabolized in the body, with less than 1% of the administered dose being excreted in the urine as unchanged FK506. The large variability in FK506 kinetics during the immediate post-operative period is attributed to the variability in the functional status of the liver in the transplant patients. Because of the long half-life of FK506, it takes more than 45 hours to reach steady-state concentrations after continuous infusion. Based on the estimated kinetic parameters, it appears that a combination of a bolus or a rapid infusion of .02 mg/kg with a continuous infusion of 0.05 mg/kg/day will provide and maintain a concentration of more than 2 ng/mL from the beginning of the drug treatment.

Treatment of premature ejaculation by glans penis augmentation using hyaluronic acid gel: a pilot study

Premature ejaculation (PE) is by far the most common male sexual complaint, with millions of men affected all over the world. It is estimated that up to 20-30% of all men may be suffering from various forms of PE. A variety of filler materials are widely used nowadays for soft tissue augmentation. The appropriate filler can restore symmetry, volume and create a smooth skin surface The aim of this pilot study was to evaluate the therapeutic effect of hyaluronic acid gel injection in patients with PE. Sixty men with self-reported PE who were referred to our outpatient andrology clinic (between January 2007 and January 2008) were included in this study. Participants were randomly assigned using random sampling numbers into two distinct groups. Group A (n = 30) received a single injection of 2 ml of hyaluronic acid gel (Hyalift 3.5% micronised hyaluronic acid) using the previously described fan technique. Group B (n = 30) received a single injection of 2 ml of hyaluronic acid gel using the multiple puncture technique. Twenty-three patients (46.9%) received injection by the fan technique, while 26 patients (53.1%) received it through the multiple-point technique. The mean intravaginal ejaculation latency time (IELT) increased significantly from 2.12 ± 1.16 to 7.71 ± 7.86 min, after 1 month of injection and then dropped to 5.32 ± 3.52 min, but still remaining significantly higher than the baseline values. Results from our present pilot study demonstrated the usefulness of the application of hyaluronic acid dermal fillers in the treatment of PE; however, further investigations in large cohorts with longer follow-up are definitely needed to obtain more consistent results.

Application of activity-based costing (ABC) for a Peruvian NGO healthcare provider

This article describes the application of activity-based costing (ABC) to calculate the unit costs of the services for a health care provider in Peru. While traditional costing allocates overhead and indirect costs in proportion to production volume or to direct costs, ABC assigns costs through activities within an organization. ABC uses personnel interviews to determine principal activities and the distribution of individual's time among these activities. Indirect costs are linked to services through time allocation and other tracing methods, and the result is a more accurate estimate of unit costs. The study concludes that applying ABC in a developing country setting is feasible, yielding results that are directly applicable to pricing and management. ABC determines costs for individual clinics, departments and services according to the activities that originate these costs, showing where an organization spends its money. With this information, it is possible to identify services that are generating extra revenue and those operating at a loss, and to calculate cross subsidies across services. ABC also highlights areas in the health care process where efficiency improvements are possible. Conclusions about the ultimate impact of the methodology are not drawn here, since the study was not repeated and changes in utilization patterns and the addition of new clinics affected applicability of the results. A potential constraint to implementing ABC is the availability and organization of cost information. Applying ABC efficiently requires information to be readily available, by cost category and department, since the greatest benefits of ABC come from frequent, systematic application of the methodology in order to monitor efficiency and provide feedback for management. The article concludes with a discussion of the potential applications of ABC in the health sector in developing countries.

Familial occurrence of discrete subaortic membrane

The first case of multiple family members with discrete subaortic membrane and no other congenital defects is presented. One family member presents with findings suggesting a forme fruste of this disease. Increased surveillance of family members of individuals with discrete subaortic membrane is warranted, as the clinical findings of mild subaortic obstruction may be indistinguishable from those of an innocent flow murmur.

Search for Dark Matter Annihilations towards the Inner Galactic Halo from 10 Years of Observations with H.E.S.S

The inner region of the Milky Way halo harbors a large amount of dark matter (DM). Given its proximity, it is one of the most promising targets to look for DM. We report on a search for the annihilations of DM particles using γ-ray observations towards the inner 300 pc of the Milky Way, with the H.E.S.S. array of ground-based Cherenkov telescopes. The analysis is based on a 2D maximum likelihood method using Galactic Center (GC) data accumulated by H.E.S.S. over the last 10 years (2004-2014), and does not show any significant γ-ray signal above background. Assuming Einasto and Navarro-Frenk-White DM density profiles at the GC, we derive upper limits on the annihilation cross section ⟨σv⟩. These constraints are the strongest obtained so far in the TeV DM mass range and improve upon previous limits by a factor 5. For the Einasto profile, the constraints reach ⟨σv⟩ values of 6×10^{-26}  cm^{3} s^{-1} in the W^{+}W^{-} channel for a DM particle mass of 1.5 TeV, and 2×10^{-26}  cm^{3} s^{-1} in the τ^{+}τ^{-} channel for a 1 TeV mass. For the first time, ground-based γ-ray observations have reached sufficient sensitivity to probe ⟨σv⟩ values expected from the thermal relic density for TeV DM particles.

Search for γ-Ray Line Signals from Dark Matter Annihilations in the Inner Galactic Halo from 10 Years of Observations with H.E.S.S

Spectral lines are among the most powerful signatures for dark matter (DM) annihilation searches in very-high-energy γ rays. The central region of the Milky Way halo is one of the most promising targets given its large amount of DM and proximity to Earth. We report on a search for a monoenergetic spectral line from self-annihilations of DM particles in the energy range from 300 GeV to 70 TeV using a two-dimensional maximum likelihood method taking advantage of both the spectral and spatial features of the signal versus background. The analysis makes use of Galactic center observations accumulated over ten years (2004-2014) with the H.E.S.S. array of ground-based Cherenkov telescopes. No significant γ-ray excess above the background is found. We derive upper limits on the annihilation cross section ⟨σv⟩ for monoenergetic DM lines at the level of 4×10^{-28}  cm^{3} s^{-1} at 1 TeV, assuming an Einasto DM profile for the Milky Way halo. For a DM mass of 1 TeV, they improve over the previous ones by a factor of 6. The present constraints are the strongest obtained so far for DM particles in the mass range 300 GeV-70 TeV. Ground-based γ-ray observations have reached sufficient sensitivity to explore relevant velocity-averaged cross sections for DM annihilation into two γ-ray photons at the level expected from the thermal relic density for TeV DM particles.

Micro-reactor for Non-catalyzed Esterification Reaction: Performance and Modeling

Y-shape micro-reactor is designed, developed and implemented to investigate the effect of reactor miniaturization on chemical engineering kinetics, where, an esterification reaction of fatty acid (2- ethyl hexanoic acid) is considered as a case study. In order to investigate the differential change of micro-reaction conversion along the channel axis; a micro-reactor with multi-channel is designed in a manner that enables collecting the samples. The kinetics of esterification reaction of ethanol and fatty acid was explored under various operating conditions; Molar Ratio (MR) of ethanol to fatty acid at temperatures 25–65 °C. The conversion reached almost 99.3 % after 30 s at MR 4:1 and 25 °C. Steady and unsteady state axial dispersion mathematical models were developed; the latter approach resulted in fair agreement with the experimental results.

The Saudi experience with neutron therapy in locally advanced head and neck cancers

The neutron therapy program at King Faisal Specialist Hospital and Research Center conducted a phase II study to evaluate the toxicity and efficacy of neutrons against conventional external megavoltage irradiation in patients with locally advanced head and neck malignancy. One hundred and nineteen patients were allocated to receive either photons (46/119) or neutrons (73/119). Radiation effects were scored according to the EORTC/RTOG criteria; data was collected weekly during treatment, once a month for the first year and at 6-month intervals subsequently. While acute effects were scored in all patients, only 59 were evaluable for late effects and locoregional control. A composite of the average reaction results were obtained using this information, to compare them in time, for acute and late effects in both arms of the study. The maximum acute reactions in the two groups were similar. In the majority of the patients (80%) acute skin and mucosal reactions occurred during the last week of treatment. The changes in the subcutaneous tissues and salivary glands became clinically apparent at 3 months or later. Salivary gland toxicity was more severe in the photon arm and the difference was statistically significant at 3 months (P = 0.04) but this was lost at 12 months. Late effects for skin and subcutaneous tissues were significantly more severe in the neutron arm with P values of 0.04 and 0.01 respectively. Three patients in the neutron arm died of grade 4 radiation complications. The local control and survival were similar in both groups.

Racial Disparity in Surgical Therapy for Thymic Malignancies

BACKGROUND

The primary curative treatment for thymic malignancies is surgery. For lung and esophageal cancer, substantive disparities in outcomes by race exist. Many of these disparities are attributed to the decreased use of surgery in non-White patients. Although thymic malignancies are treated by the same specialists as lung and esophageal cancer, it is unknown if there are racial disparities in the treatment of thymic malignancies.

RESEARCH QUESTION

Do racial disparities exist in the surgical treatment of thymic malignancies?

STUDY DESIGN AND METHODS

A retrospective cohort analysis was performed using the National Cancer Data Base of patients diagnosed with thymoma and thymic carcinoma between 2004 and 2016. Univariate comparisons of demographics were compared using χ 2 and rank-sum tests. Multivariable analysis was performed to determine if race was an independent variable associated with receiving surgical resection. Preoperative and postoperative care was compared between races.

RESULTS

Seven thousand four hundred eighty-nine patients met inclusion criteria. Four thousand nine hundred sixty-two (66%) were White, 1,311 (18%) were Black, 487 (7%) were Hispanic, 580 (8%) were Asian or Pacific Islander, and 143 (2%) were other races. Black patients with thymic malignancies were more likely to have a median income < $38,000 and not received surgery. Black and Hispanic patients had the lowest median age (54.3 and 53.6 years, respectively) and were most likely to be uninsured (8.2% and 12.5%, respectively). White patients received surgical therapy 1 week sooner and had a postoperative length of stay 1.5 days shorter than Black patients. Multivariable analysis controlling for age, sex, tumor size, insurance status, comorbidity score, histology, and facility type showed that race remained independently associated with the receipt of surgical resection. White patients had the greatest likelihood of receiving surgery with Black patients being least likely to receive surgery (OR, 0.60).

INTERPRETATION

A racial disparity exists in surgical therapy for thymic malignancies.

The Lebanese left ventricular assist device experience, a success story despite the odds

BACKGROUND AND AIM

Heart failure is still a leading cause of mortality and morbidity. Assist devices are reserved for advanced heart failure patients with no other therapeutic options. We aim in this paper to describe the characteristics and outcome of Lebanese left ventricular assist device (LVAD) patients.

RESULTS

From 2010 till December 2019, 78 patients were implanted with assist devices at the Beirut cardiac Institute, 82 pumps were used. To the most recent follow up after 10 years, 26 patients died (34%). 24 patients of 35 (68%) survived more than 5 years. Seven patients only (9%) died during one month of surgery. One year mortality was 19% (15 patients). The leading cause of early mortality was infection, whereas cerebrovascular accidents CVA were the leading cause of late mortality. Pump thrombosis occurred in 12% of the cases. The most serious long term complication was haemorrhagic CVA. Only seven patients (9%) received heart transplantation, with a mean time on support prior to transplantation of 1303 ± 213 days.

CONCLUSION

In this manuscript we reported the characteristics and outcome of the largest population of LVAD patients in Lebanon. The survival rate was 81% at one year. These findings were comparable to the international registries except for rates of heart transplantation. More efforts should be made to encourage organ donation in Lebanon.

Mathematical Modeling, Verification and Optimization for Catalytic Membrane Esterification Micro-reactor

Analysis of efficient production of ethyl acetate utilizing a Catalytic Membrane Micro-Reactor (CMMR) was theoretically investigated and verified using published results for the esterification reaction. Grafted sulfonic groups in the pores of a polyethersulfone membrane catalyzed the reaction. Theoretical analysis of the catalytic membrane reactor was achieved through development of a lumped parameter model to describe the CMMR behavior and performance. The developed model was solved numerically for different design and operating conditions using MATLAB Simulink software. The model parameters were verified and validated using the experimental results to achieve a reliable tool for design, replication, scaling-up, and optimization. The approach to maximum conversion was simulated. Cumulative yield per unit time was investigated to determine the optimum process time. Membrane regeneration was conducted and the regeneration time was determined as well in order to reuse the membrane for other cycles. Reactor scaling-up was studied using the model for process design.

Skull base chordomas presenting with abducens nerve deficits: clinical characteristics and predictive factors for deficit improvement or resolution

OBJECTIVE

Skull base chordomas (SBCs) often present with cranial nerve (CN) VI deficits. Studies have not assessed the prognosis and predictive factors for CN VI recovery among patients presenting with CN VI deficits.

METHODS

The medical records of patients who underwent resection for primary chordoma from 2001 to 2020 were reviewed. Those presenting with CN VI palsy were identified. The extent of CN VI deficit was determined to be partial or complete based on the Scott-Kraft score. The change in deficit from baseline was recorded within 3 days of surgery and at the 6-month follow-up. The postoperative course was followed until partial and/or complete deficit recovery. Univariate logistic regression models were created to predict improvement or resolution of CN VI deficit.

RESULTS

A total of 113 patients with primary SBC were identified, 34 of whom presented with CN VI deficits: 24 (73%) with partial and 9 (27%) with complete deficits. The extent of deficit in 1 patient was unable to be determined. The median duration of deficit preoperatively was 3.6 months, and CN VI was most commonly radiographically abutted at the prepontine cistern and Dorello's canal. Twenty-three (68%) patients experienced at least partial CN VI recovery (mean 61 days, range 2-174 days). Nineteen (56%) patients experienced complete CN VI recovery (mean 162 days, range 2-469 days). No patients whose CN VI deficit worsened immediately after surgery achieved improvement in CN VI function at 6 months (p = 0.001). Preoperative partial (relative to complete) CN VI deficit was associated with greater odds of CN VI deficit improvement by 6 months (OR 7.7, p = 0.028). Factors not associated with deficit resolution included duration of deficit, CN VI involvement by tumor, total segments abutted by tumor, sex, age at diagnosis, gross-total resection, tumor volume, and adjuvant radiation therapy, although this analysis may have been underpowered to detect small differences.

CONCLUSIONS

Overall, 68% of patients achieved at least partial recovery in CN VI function after endoscopic skull base surgery. Among patients with partial CN VI palsy at baseline, 83% achieved CN VI recovery within 6 months and 75% achieved complete recovery within 14 months. For patients who presented with a complete CN VI deficit, within those same time frames, 33% and 11% achieved partial and complete recovery, respectively. Complete preoperative CN VI deficit was associated with lower odds of CN VI recovery by 6 months. The duration of preoperative deficit does not predict functional CN VI recovery.

[Farber disease: a cause of hoarseness of the voice in children]

Farber's disease (disseminated lipogranulomatosis) is an autosomal recessive disease characterized by deposition of glycolipid ceramide in different tissues due to deficiency of lysosomal acid ceramidase. The disease starts to manifest at the age of four months by a hoarse cry or swollen tender joints followed by subcutaneous nodules. This disease is fatal in the first years of life and no treatment is known until now. This study presents four cases of Farber's disease who all presented by hoarseness of voice, polyarthritis and subcutaneous nodules. After clinical examination, the diagnosis was confirmed by fiberoptic flexible nasopharyngolaryngoscopy which showed the presence of vocal folds thickening in all patients and affection of the cricoarytenoid joint in one patient and biopsy from the subcutaneous nodules which showed infiltration of the deep dermis and subcutaneous tissues by fibroblasts and large foamy histiocytes.

Outcomes of bariatric surgery in the setting of compensated advanced chronic liver disease associated with clinically significant portal hypertension: a multicenter, retrospective, cohort study on feasibility and safety

BACKGROUND

The obesity epidemic has led to an increase in the proportion of patients with chronic liver disease due to metabolic associated steatosic liver disease and in the prevalence of obesity in patients with cirrhosis. Metabolic and bariatric surgery (MBS) has been proven to determine weight loss, obesity-related medical problems remission, and liver steatosis, inflammation, and fibrosis improvement. However, cirrhosis and portal hypertension are well-known risk factors for increased morbidity and mortality after surgery. The aim of this study is to evaluate the safety of MBS in patients with compensated advanced chronic liver disease (cALCD) and clinically significant portal hypertension (CSPH).

MATERIAL AND METHODS

This is an international, multicentric, retrospective study on 63 individuals affected by obesity with cALCD and CSPH who underwent MBS in tertiary referral centers with experts hepatobiliary surgeons between January 2010 and October 2022. The primary endpoint was postoperative mortality at 90 days. The secondary endpoints included postoperative weight loss at last follow-up and postoperative complication rate. In addition, the authors performed subgroup analyses of Child-Pugh (A vs. B) score, MELD (≤9 vs. >9) score, and type of surgery.

RESULTS

One patient (1.6%) experienced gastric leakage and mortality. There were three (5%) reported cases of portal vein thrombosis, two (3%) postoperative acute renal failure, and one (1.6%) postoperative encephalopathy. Child-Pugh score A resulted to be a protective factor for intraoperative bleeding requiring transfusion at univariate analysis (OR: 0.73, 95% CI: 0.55-0.97, P =0.046) but not at multivariate analysis. MELD>9 score and the type of surgery did not result to be a risk factor for any postoperative complication.

CONCLUSION

MBS is safe in patients with cALCD and CSPH performed in tertiary bariatric referral centers with hepatobiliary expert surgeons. Larger, prospective studies with longer follow-up periods are needed to confirm these results.

MO789SERUM SOLUBLE TRANSFERRIN RECEPTOR IS A PROMISING MARKER OF IRON DEFICIENCY ANEMIA IN PREVALENT HEMODIALYSIS PATIENTS

Background and Aims

End stage renal disease (ESRD) is chronic inflammatory condition which affects iron parameters. Serum soluble transferrin receptor (sTfR) is a reliable indicator for assessing iron status in inflammatory conditions. This study evaluates the usefulness of serum sTfR in iron deficiency anemia detection in prevalent hemodialysis patients.

Method

This case-control study included 40 ESRD patients on conventional hemodialysis with CRP&gt;10, 40 ESRD patients with CRP&lt;10 and 8 apparently healthy controls. Serum sTfR was measured for all patients and controls.

Results

STFRs predicts iron deficiency anemia in prevalent hemodialysis patients at cut off value 12.5 mg/l with area under curve 0.949, sensitivity 88.75, specificity 100, PPV 100% and NPV 47.1%. The prevalence of STFRs in patients with CRP&lt;10 was 85%, while in patients with CRP&gt;10 was 92.5% (P-value 0.288). Patients who have elevated STFRs have risk 1.22 times to have iron deficiency anemia if CRP &lt;10 (odds ratio: 1.22) and 3.14 times if CRP&gt;10 (odds ratio: 3.14). There was significant difference on comparing patients with CRP&lt;10, CRP&gt;10 and control as regard haemoglobin and STFR with P-value 0.0001 and 0.0001 respectively. Post Hoc analysis showed significant difference between the patients with CRP&lt;10 and control also in patients with CRP&gt;10 and control as regard haemoglobin and STFR (p value &lt;0.0001). on comparing patients with CRP&lt;10 with patients with CRP&gt;10 there was significant difference in STFRs p value 0.0001 despite no significant difference in haemoglobin (p value 0.642) and classic iron markers (s.iron, TIBC, TSAT) with p value 0.701, 0.192, 0.382 respectively. Serum STFRs was negatively correlated with s.iron and Kt\v in patients with CRP &lt;10 (r -0.372, P-value 0.018) and (r-0.416, p value 0.008) respectively.

Conclusion

Serum soluble transferrin receptor is a highly sensitive and specific marker of iron deficiency anemia in hemodialysis patients especially with high CRP level.