Feasibility Study of Single-Photon Emission Computed Tomography with Iodine-123 Labeled Metaiodobenzylguanidine for Preclinical Evaluation of Labetalol as a ß-Adrenergic Receptor Blocker.

Among clinically used radiopharmaceuticals, iodine-123 labeled metaiodobenzylguanidine ([123I]mIBG) serves for diagnosing neuroendocrine tumors and obtaining images of myocardial sympathetic innervation. mIBG, a structural analogue of norepinephrine (NE), a neurotransmitter acting in peripheral and central nerves, follows a pathway similar to NE, transmitting signals through the NE transporter (NET) located at synaptic terminals. It moves through the body without decomposing, enabling noninvasive image evaluation. In this study, we aimed to quantify [123I]mIBG uptake in the adrenal glands using small animal single-photon emission computed tomography/computed tomography (SPECT/CT) images post [123I]mIBG administration. We investigated the possibility of assessing the effectiveness of ß-adrenergic receptor blockers by quantifying SPECT/CT images and biodistribution results to determine the degree of [123I]mIBG uptake in the adrenal glands treated with labetalol, a known ß-adrenergic receptor blocker. Upon intravenous administration of [123I]mIBG to mice, SPECT/CT images were acquired over time to confirm the in vivo distribution pattern, revealing a clear uptake in the adrenal glands. Labetalol inhibited the uptake of [123I]mIBG in cell lines expressing NET. A decrease in [123I]mIBG uptake in the adrenal glands was observed in the labetalol-treated group compared with the normal group through SPECT/CT imaging and biodistribution studies. These results demonstrate that SPECT/CT imaging with [123I]mIBG could be applicable for evaluating the preclinical efficacy of new antihypertensive drug candidates such as labetalol, a ß-adrenergic receptor blocker.

Comparison of labetalol and lidocaine in induction of controlled hypotension in tympanoplasty: a randomized clinical trial.

OBJECTIVES: This study aimed to compare the efficacy of labetalol and lidocaine in tympanoplasty surgery, specifically evaluating their impact on hemodynamic changes and perioperative outcomes. METHODS: A randomized controlled trial was conducted with 64 patients scheduled for tympanoplasty. Patients were randomly assigned to receive either 0.5-2 mg/min labetalol or 1.5 mg/kg/h lidocaine 1% to achieve controlled hypotension during surgery. The efficacy of the drugs was assessed by comparing the Mean Arterial Pressure (MAP), surgeon's satisfaction, time to target MAP, bleeding volume, postoperative pain scores, the need for analgesic medication in recovery, sedation, and other additional parameters. RESULTS: The hemodynamic parameters showed a similar trend over time in both the labetalol and lidocaine groups. The median bleeding volume in the labetalol group (10 cc) was lower than that in the lidocaine group (30 cc), although this difference was not statistically significant (p = 0.11). Similarly, surgeon's satisfaction level, pain intensity, and sedation level in the recovery room did not show statistically significant differences between the two groups (p > 0.05). The duration of surgery, recovery stay, and extubation time also did not significantly differ between the groups. Both medications took approximately the same time (20 min) to reach the target MAP and exhibited comparable hemodynamic responses (p > 0.05). CONCLUSION: Both labetalol and lidocaine effectively achieved controlled hypotension during tympanoplasty surgery, thereby improving surgical conditions. The choice of medication should be based on individual patient characteristics and the anesthesiologist's judgment. LEVEL OF EVIDENCE: II.

Buffalo yogurt fermented with commercial starter and Lactobacillus plantarum originating from breast milk lowered blood pressure in pregnant hypertensive rats.

Nutritional therapy, which may have advantages over medication, is being investigated as a novel treatment for pregnancy-induced hypertension. Several studies have shown that probiotic yogurt supplementation during pregnancy has beneficial effects on maternal and fetal health. In this study, fermented buffalo milk was produced with yogurt culture and Lactobacillus plantarum B, a probiotic isolated from healthy breast milk with high angiotensin-converting enzyme inhibitory activity. The fermentation conditions under which the angiotensin-converting enzyme (ACE) inhibitory activity reached 84.51% were optimized by the response surface method as follows: 2 × 106 cfu/mL of L. plantarum B, yogurt culture 2.5 × 105 cfu/mL, and 8 h at 37°C. The distribution of ACE inhibitory peptides from fermented buffalo milk and fermented cow milk were further analyzed by liquid chromatography-mass spectrometry. By searching according to the structural features of ACE inhibitory peptides, 29 and 11 peptides containing ACE inhibitory peptide features were found in fermented buffalo milk and fermented cow milk, respectively. To investigate the in vivo antihypertensive activity of fermented buffalo milk, 18 pregnant rats were divided into 3 groups (n = 6 in each group) and administered 10 mL of normal saline, yogurt (20 mg/kg), or labetalol hydrochloride (4 mg/kg) daily from the beginning of pregnancy to parturition. To induce hypertension, methyl nitrosoarginine (125 mg/kg) was injected subcutaneously every day from d 15 of pregnancy to the day of delivery. Blood pressure was not significantly changed in the yogurt and labetalol groups after induction of hypertension and was lower compared with the normal saline group, but there was no difference between the yogurt and labetalol groups. This implied that the buffalo yogurt had a preventive and antihypertensive effect in the pregnancy-induced hypertensive rat model. Further studies to determine the mechanism of action, as well as a randomized control trial, are warranted.

Haemodynamic effects of labetalol in isoflurane-anaesthetized dogs that received dexmedetomidine: A randomized clinical trial.

OBJECTIVE: To test whether labetalol improved cardiovascular function in anaesthetized dogs injected with dexmedetomidine. STUDY DESIGN: Prospective, randomized, blinded, clinical trial. ANIMALS: A group of 20 healthy client-owned dogs undergoing ovariohysterectomy. METHODS: Each dog received dexmedetomidine (5 µg kg-1) and methadone (0.2 mg kg-1) intramuscularly. General anaesthesia was induced with propofol and maintained with isoflurane in oxygen. All dogs were mechanically ventilated, and epidural anaesthesia with lidocaine was performed. Standard anaesthetic monitoring, invasive blood pressure, oesophageal Doppler and near-infrared tissue perfusion/oxygenation were applied. Peak velocity (PV), mean acceleration and stroke distance (SD) from the oesophageal Doppler were recorded. Arterial elastance (Ea) was calculated. Tissue oxygenation (rStO2) was also recorded. Prior to surgery, animals received either 0.1 mg kg-1 of labetalol intravenously (IV) over 60 seconds or the equivalent volume of saline. Data were recorded for 20 minutes. Age, weight and propofol dose were compared with a Wilcoxon rank-sum test. The effects of time, treatment and their interaction with haemodynamic and perfusion variables were analysed with mixed-effect models and Tukey's post hoc tests. RESULTS: Significant effects of the interaction between treatment and time were observed whereby heart rate (HR) was higher in dogs given labetalol (p = 0.01), whereas arterial blood pressure and Ea were lower (p < 0.01). Similarly, PV, SD and rStO2 were higher in the labetalol group, and significant effects were detected for the interaction between treatment and time (p < 0.01). CONCLUSIONS AND CLINICAL RELEVANCE: Labetalol at a dose of 0.1 mg kg-1 IV in dogs under general anaesthesia and administered a pre-anaesthetic medication of dexmedetomidine produced mild vasodilation (reduction of Ea), resulting in an increase in HR and left ventricular outflow. Although labetalol could be an effective option to achieve haemodynamic optimization after dexmedetomidine-induced vasoconstriction, future studies are needed to assess long-term effects.

Uso de labetalol frente a nifedipino en la preeclampsia / Use of labetalol vs nifedipine in preeclampsia

Fundamento: La preeclampsia es un estado de vasoconstricción generalizado asociado a la disfunción del epitelio vascular en vez de vasodilatación propia del embarazo, caracterizada por la hipertensión proteinuria a partir de la semana 20, acompañada a veces de edemas; asimismo constituye un peligro de salud para la madre y el feto. El tratamiento clínico tradicional utiliza fármacos antihipertensivos por vía oral, entre los que se mencionan el labetalol y nifedipino de liberación prolongada. Objetivo: Analizar la efectividad del labetalol y del nifedipino como tratamiento antihipertensivo relacionado con preeclampsia. Metodología: Se recurrió a fuentes de consulta encontradas en Google Scholar, Science Direct, SciELO, Pubmed, Medes y Elsevier. De 211 fuentes se seleccionaron 31 de acuerdo con criterios de inclusión y exclusión. Conclusiones: Por consenso se ha determinado que en la mayor parte de fuentes de consulta el nifedipino por vía oral es más efectivo que el labetalol en el tratamiento de la preeclampsia.

Background: Pre-eclampsia is a generalized vasoconstriction state associated with vascular epithelial dysfunction rather than the vasodilation characteristic of pregnancy, characterized by proteinuric hypertension from the 20th week of pregnancy, sometimes associated with edema; it also causes health risks to the mother and fetus. Traditional clinical treatment uses oral antihypertensive drugs, among these labetalol and extended-release nifedipine are included. Objective: To analyze the efficacy of labetalol and nifedipine as an antihypertensive treatment in pre-eclampsia. Methodology: Reference sources found in Google Scholar, Science Direct, SciELO, Pubmed, Medes and Elsevier were used. Out of 211 sources, 31 were selected according to inclusion and exclusion criteria. Conclusions: It has been determined by majority consensus that oral nifedipine is more effective than labetalol in pre-eclampsia treatment.

Precipitation of sugammadex with nicardipine and labetalol: A laboratory research.

There is a paucity of clinical data about whether sugammadex forms precipitates with other medications. This laboratory experimental study was performed to determine the drugs that produce precipitates with sugammadex. Samples of 1 ml of sugammadex were prepared in transparent cylinders, to which 1 ml of test drugs (rocuronium, neostigmine, glycopyrrolate, atropine, nitroglycerin, dobutamine, dopamine, epinephrine, vasopressin, norepinephrine, phenylephrine, ephedrine, esmolol, nicardipine, and labetalol) was added. The precipitation reaction was observed visually and via light microscope. The pH of each drugs before and after mixing with sugammadex was measured. White crystals were formed when sugammadex was mixed with nicardipine or labetalol. Sugammadex formed precipitate when mixed with nicardipine or labetalol. Sufficient fluid flushing is required between injections of each drug to prevent these reactions.

A Giant Pheochromocytoma Presenting in Pheochromocytoma Crisis: A Case Report.

Giant pheochromocytomas are rare tumors, with the majority being clinically silent. Clinically manifesting pheochromocytoma can present with symptoms of catecholamine excess, but nonspecific symptoms and variable clinical patterns of hypertension make it difficult to diagnose. Missing the diagnosis can lead to cardiovascular catastrophes like a pheochromocytoma crisis and even death. We report a 45-year-old woman on antihypertensives, repeatedly visiting a hospital for recurrent headaches finally presented in a hypertensive crisis at an emergency department. Management was started along with an injection of labetalol, which led to an unpredicted abrupt blood pressure fall, and was successfully resuscitated. Imaging and plasma metanephrine studies revealed an underlying giant pheochromocytoma, which was cured after successful surgical resection. A high degree of clinical suspicion, elaborate and focused history-taking, and initial ultrasound imaging can guide us toward the early diagnosis of pheochromocytoma. Before the alpha blockade, beta-blockers should not be used in any cases of pheochromocytoma. Keywords: case reports; headache; hypertension; pheochromocytoma.

Comparing the efficacy of oral labetalol with oral amlodipine in achieving blood pressure control in women with postpartum hypertension: randomized controlled trial (HIPPO study-Hypertension In Pregnancy & Postpartum Oral-antihypertensive therapy).

De novo - or as a continuum of antenatal hypertension -postpartum hypertension complicates ~2% of pregnancies. Many maternal complications, such as eclampsia and cerebrovascular accidents, occur in the postpartum period. Despite widespread use of antihypertensives during pregnancy and childbirth, there is a paucity of data on preferred medications in the postpartum period. This randomized controlled study enrolled 130 women who were started on antihypertensives. They were randomized to receive oral Labetalol(LAB, maximum 900 mg per day in three doses) or oral Amlodipine(AML, maximum 10 mg per day given in two doses). In the immediate postpartum, all women were closely monitored for neurological symptoms, blood pressure, heart rate, respiratory rate, urine output, and deep tendon reflex. The primary outcome was the time to achieve sustained blood pressure control for 12 h from the initiation of medication; secondary outcomes included side effects of both medications. Mean time to achieve sustained blood pressure control was lower in women who received AML than in those who received LAB-(mean difference 7.2 h; 38 95% CI 1.4, 12.9, p = 0.011). There were fewer severe hypertensive episodes among those with AML than in those who received LAB. However, the proportion of women who continued to require antihypertensives at discharge was higher in the AML group than in the LAB group (55.4% versus 32.3%, p = 0.008). None of the participants developed drug-related side effects. Among women with postpartum persistence or new-onset hypertension, oral AML achieved sustained blood pressure control in a shorter duration, with fewer hypertensive emergencies than oral LAB. (CTRI/2020/02/023236).Trial Registration details: The study protocol was registered with Clinical Trial Registry of India with CTRI Number CTRI/2020/02/023236 dated 11.02.2020. Protocol can be accessed at https://www.ctri.nic.in/Clinicaltrials/pdf_generate.php?trialid=40435&EncHid=&modid=&compid=%27,%2740435det%27 .

Treatment of Post-Coarctectomy Hypertension With Labetalol-A 9-Year Single-Center Experience.

BACKGROUND: Although considering the pathophysiology of post-coarctectomy hypertension, ß-blockers should be effective, experience with labetalol for treatment is limited in the literature. METHODS: Retrospective collection and analysis of data in children aged ≤6 years following coarctectomy in our tertiary care university medical center between January 2009 and June 2018. RESULTS: 96 patients were included, 45 were treated with intravenous labetalol and 51 received no treatment. Median time to maximum dose received (median 1.1 mg/kg/h) was 2.7 h, and median time to the reduction of labetalol dose was 8.3 h. No antihypertensives had to be added. In one child, labetalol was switched to nitroprusside due to bronchoconstriction. Of patients receiving intravenous labetalol, 48% had been switched to oral labetalol at discharge. CONCLUSIONS: Intravenous labetalol is a fast, effective, and safe drug to treat hypertension following aortic coarctation repair. Labetalol is easily converted to oral therapy when the continuation of treatment is considered necessary.

In Vitro Toxicological Profile of Labetalol-Folic Acid/Folate Co-Administration in H9c2(2-1) and HepaRG Cells.

Background and Objectives: The consumption of dietary supplements has increased over the last decades among pregnant women, becoming an efficient resource of micronutrients able to satisfy their nutritional needs during pregnancy. Furthermore, gestational drug administration might be necessary to treat several pregnancy complications such as hypertension. Folic acid (FA) and folate (FT) supplementation is highly recommended by clinicians during pregnancy, especially for preventing neural tube birth defects, while labetalol (LB) is a ß-blocker commonly administered as a safe option for the treatment of pregnancy-related hypertension. Currently, the possible toxicity resulting from the co-administration of FA/FT and LB has not been fully evaluated. In light of these considerations, the current study was aimed at investigating the possible in vitro cardio- and hepato-toxicity of LB-FA and LB-FT associations. Materials and Methods: Five different concentrations of LB, FA, FT, and their combination were used in myoblasts and hepatocytes in order to assess cell viability, cell morphology, and wound regeneration. Results: The results indicate no significant alterations in terms of cell viability and morphology in myoblasts (H9c2(2-1)) and hepatocytes (HepaRG) following a 72-h treatment, apart from a decrease in the percentage of viable H9c2(2-1) cells (~67%) treated with LB 150 nM−FT 50 nM. Additionally, LB (50 and 150 nM)−FA (0.2 nM) exerted an efficient wound regenerating potential in H9c2(2-1) myoblasts (wound healing rates were >80%, compared to the control at 66%), while LB-FT (at all tested concentrations) induced no significant impairment to their migration. Conclusions: Overall, our findings indicate that LB-FA and LB-FT combinations lack cytotoxicity in vitro. Moreover, beneficial effects were noticed on H9c2(2-1) cell viability and migration from LB-FA/FT administration, which should be further explored.

Case Report: Giant Paraganglioma of the Skull Base With Two Somatic Mutations in SDHB and PTEN Genes.

Head and neck paragangliomas (HNPGLs) are neuroendocrine tumors. They arise from the parasympathetic ganglia and can be either sporadic or due to hereditary syndromes (up to 40%). Most HNPGLs do not produce significant amounts of catecholamines. We report a case of a giant paraganglioma of the skull base with an unusually severe presentation secondary to excessive release of norepinephrine, with a good outcome considering the severity of disease. A 39-year-old Caucasian woman with no prior medical history was found unconscious and emaciated in her home. In the intensive care unit (ICU) the patient was treated for multi-organ failure with multiple complications and difficulties in stabilizing her blood pressure with values up to 246/146 mmHg. She was hospitalized in the ICU for 72 days and on the 31st day clinical assessment revealed jugular foramen syndrome and paralysis of the right n. facialis. A brain MRI confirmed a right-sided tumor of the skull base of 93.553 cm3. Blood tests showed high amounts of normetanephrine (35.1-45.4 nmol/L, ref <1.09 nmol/L) and a tumor biopsy confirmed the diagnosis of a paraganglioma. Phenoxybenzamine and Labetalol were used in high doses ((Dibenyline®, 90 mg x 3 daily) and labetalol (Trandate®, 200 + 300 + 300 mg daily) to stabilize blood pressure. The patient underwent two tumor embolization procedures before total tumor resection on day 243. Normetanephrine and blood pressure normalized after surgery (0.77 nmol/L, ref: < 1.09 nmol/L). The damage to the cranial nerve was permanent. Our patient was comprehensively examined for germline predisposition to PPGLs, however we did not identify any causal aberrations. A somatic deletion and loss of heterozygosity (LOH) of the short arm (p) of chromosome 1 (including SDHB) and p of chromosome 11 was found. Analysis showed an SDHB (c.565T>G, p.C189G) and PTEN (c.834C>G, p.F278L) missense mutation in tumor DNA. The patient made a remarkable recovery except for neurological deficits after intensive multidisciplinary treatment and rehabilitation. This case demonstrates the necessity for an early tertiary center approach with a multidisciplinary expert team and highlights the efficacy of the correct treatment with alpha-blockade.

Application of comprehensive bioinformatics approaches to reconnoiter crucial genes and pathways underpinning hepatocellular carcinoma: a drug repurposing endeavor.

Hepatocellular carcinoma (HCC) is the fifth most common neoplasm in the world. Chronic inflammation of liver and associated wound healing processes collectively contribute to the development of cirrhosis which further progresses to dysplastic nodule and then to HCC. Etiological mediators and ongoing manipulations at cellular level in HCC are well established; however, key protein interactions and genetic alterations involved in stepwise hepatocarcinogenic pathways are seldom explored. This study aims to unravel novel targets of HCC and repurpose the FDA-approved drugs against the same. Genetic data pertinent to different stages of HCC were retrieved from GSE6764 dataset and analyzed via GEO2R. Subsequently, protein-protein interaction network analysis of differentially expressed genes was performed to identify the hub genes with significant interaction. Hub genes displaying higher interactions were considered as potential HCC targets and were validated thorough UALCAN and GEPIA databases. These targets were screened against FDA-approved drugs through molecular docking and dynamics simulation studies to capture the drugs with potential activity against HCC. Finally, cytotoxicity of the shortlisted drug was confirmed in vitro by MTT assay. CDC20 was identified as potential druggable target. Docking, binding energy calculations, and dynamic studies revealed significant interaction exhibited by Labetalol with CDC20. Further, in MTT assay, Labetalol demonstrated an IC50 of 200.29 µg/ml in inhibiting the cell growth of HepG2 cell line. In conclusion, this study discloses a series of key genetic underpinnings of HCC and recommends the pertinence of labetalol as a potential repurposable drug against HCC.

Isotopic response of labetalol-associated lichen planus pemphigoides on an old radiation site: A case report.

Over the years, the occurrences of different types of skin disorders arising from radiation sites have been observed and studied. Examples include autoimmune blistering diseases such as pemphigus, pemphigoid, and interface or inflammatory reaction patterns such as lichen planus, lupus erythematosus, and Stevens-Johnson syndrome. The phenomenon whereby a new skin disorder arises from a previously healed or irradiated site is called an isotopic response, described as a type of Koebner phenomenon. Ionizing radiation itself can profoundly affect the skin. Both early and late changes can present, which typify the progression of changes following irradiation of the skin. Herein, we report a rare case of labetalol-associated lichen planus pemphigoides that occurred at the site treated with radiation for a soft tissue malignancy after 19 years as a result of an isotopic response. The rash was well-controlled after therapy and kept a 4-year remission. The same skin reaction recurred after the reintroduction of labetalol 4 years later.

Retrospective evaluation of labetalol as antihypertensive agent in dogs.

BACKGROUND: To evaluate the effect on arterial blood pressure (ABP) of labetalol infusion as treatment for perioperative non nociceptive acute hypertension in dogs. The clinical records of dogs receiving intra or postoperative labetalol infusion were retrospectively reviewed. Invasive systolic (SAP), mean (MAP) and diastolic (DAP) arterial pressure and heart rate (HR) before labetalol infusion (T0) and 15, 30, 45 and 60 min (T1, T2, T3 and T4 respectively) after infusion were retrieved. The dose rate of labetalol infusion and use of concurrently administered drugs that could have potentially affected ABP and/or HR were also recorded. ANOVA for repeated measures and Dunnett's multiple comparison test were used to determine the effect of labetalol on ABP and HR. Differences were considered significant when p < 0.05. RESULTS: A total of 20 dogs met the inclusion criteria, and hypertension was documented after craniotomy (12/20), adrenalectomy (4/20) and other procedures (4/20). Five dogs received labetalol intraoperatively, 14 postoperatively, and 1 during the surgical procedure and recovery. Median infusion duration and rate were 463 (60-2120) minutes and 1.1 (0.2-3.4) mg/kg/h respectively. Median loading dose was 0.2 (0.2-0.4) mg/kg. Labetalol produced a significant decrease in SAP and DAP at all time points compared to T0 (p < 0.05), while the effect was not significant at T1 for MAP (p = 0.0519). Median maximum MAP decrease was 31 (20-90) mmHg. Heart rate did not increase significantly during treatment (p = 0.2454). Acepromazine given before or during labetalol treatment did not reduce significantly ABP (p = 0.735). CONCLUSIONS: Labetalol produced a reliable and titratable decrease in ABP with non significant increase in HR.

Effects of nitroglycerin versus labetalol on peripheral perfusion during deliberate hypotension for sinus endoscopic surgery: a randomized, controlled, double-blinded trial.

BACKGROUND: Deliberate hypotension is used to provide a bloodless field during functional endoscopic sinus surgery; however, the impact of controlled hypotension during anesthesia on peripheral tissue perfusion has not been extensively evaluated. The aim of this study was to compare the impact of nitroglycerin- versus labetalol-induced hypotension on peripheral perfusion. METHODS: The present randomized, double-blinded, controlled trial included adult patients undergoing endoscopic sinus surgery. Patients were allocated to one of two groups according to the drug received for induction of deliberate hypotension: nitroglycerin (n = 20) or labetalol (n = 20). Mean arterial pressure was maintained at 55-65 mmHg in both groups. Both study groups were compared according to pulse oximeter-derived peripheral perfusion index (primary outcome), serum lactate level, mean arterial pressure, heart rate, surgical field score, and intraoperative blood loss. RESULTS: Forty patients were included in the final analysis. The nitroglycerin group exhibited a higher peripheral perfusion index at nearly all records (p < 0.0001) and lower postoperative serum lactate levels (1.3 ± 0.2 mmol/L vs. 1.7 ± 0.4 mmol/L; p = 0.001) than the labetalol group. The peripheral perfusion index was higher in the nitroglycerin group than at baseline at most intraoperative readings. The median surgical field score was modestly lower in the labetalol group than in the nitroglycerin group in the first 20 min (2 [interquartile range (IQR) 2-2.5] versus 1.5 [IQR 1-2]; p = 0.001). Both groups demonstrated comparable and acceptable surgical field scores in all subsequent readings. CONCLUSION: Nitroglycerin-induced deliberate hypotension was accompanied by higher peripheral perfusion index and lower serum lactate levels than labetalol-induced deliberate hypotension during sinus endoscopic surgery. TRIAL REGISTRATION: The study was registered at clinicaltrials registry system with trial number: NCT03809065. Registered at 19 January 2019. This study adheres to CONSORT guidelines.

Use of a non-hepatic cell line highlights limitations associated with cell-based assessment of metabolically induced toxicity.

Metabolically induced drug-toxicity is a major cause of drug failure late in drug optimization phases. Accordingly, in vitro metabolic profiling of compounds is being introduced at earlier stages of the drug discovery pipeline. An increasingly common method to obtain these profiles is through overexpression of key CYP450 metabolic enzymes in immortalized liver cells, to generate competent hepatocyte surrogates. Enhanced cytotoxicity is presumed to be due to toxic metabolite production via the overexpressed enzyme. However, metabolically induced toxicity is a complex multi-parameter phenomenon and the potential background contribution to metabolism arising from the use of liver cells which endogenously express CYP450 isoforms is consistently overlooked. In this study, we sought to reduce the potential background interference by applying this methodology in kidney-derived HEK293 cells which lack endogenous CYP450 expression. Overexpression of CYP3A4 resulted in increased HEK293 proliferation, while exposure to four compounds with reported metabolically induced cytotoxicity in liver-derived cells overexpressing CYP3A4 resulted in no increase in cytotoxicity. Our results indicate that overexpression of a single CYP450 isoform in hepatic cell lines may not be a reliable method to discriminate which enzymes are responsible for metabolic induced cytotoxicity.

An 80-Year-Old Man With a 24-Hour History of Epigastric Pain.

CASE PRESENTATION: An 80-year-old man was admitted to our hospital with 24 hours of epigastric pain. The pain was described as sharp, episodic, nonradiating, and without an identifiable provoking factor. Associated symptoms included nausea and nonbloody vomiting. He denied dyspnea, angina, fevers, chills, dysphagia, diarrhea, melena, or hematochezia. He had taken less than 2 g of acetaminophen earlier in the day without symptomatic relief. He had a 30-pack-year smoking history but quit over 25 years ago. He did not drink alcohol or use illicit drugs. He had a medical history of end-stage renal disease, for which he had undergone hemodialysis; hypertension; metastatic prostate cancer, for which he had received androgen deprivation therapy; and abdominal aortic aneurysm. His surgical history included a remote endovascular repair of the abdominal aortic aneurysm. His medications included amlodipine, losartan, carvedilol, sevelamer, and leuprolide.

Comparing the effect of dexmedetomidine and labetalol on hemodynamic variables in patients undergoing microlaryngoscopy.

INTRODUCTION: This study was conducted to compare the effect of dexmedetomidine and labetalol on hemodynamic variables in patients undergoing microlaryngoscopy. MATERIAL AND METHODS: In this randomized clinical trial study 70 patients undergoing microlaryngoscopy were involved. The patients were randomly assigned into two groups. Patients in dexmedetomidine group received 0.5 µg/kg of dexmedetomidine diluted in 100 ml of saline solution and the patients in the second group received 0.25 mg/kg of labetalol before anesthesia induction. At the beginning of the surgery, dexmedetomidine was infused at the dose of 0.4 µg/kg/h in the dexmedetomidine group, and labetalol at the dose of 1.8 mg/kg/h in the labetalol group. Patients' systolic blood pressure, diastolic blood pressure, mean arterial blood pressure and heart rate at different times and anesthesia and surgery duration, recovery time and dose of prescribed propofol were recorded and compared between two groups. RESULTS: There was a significant difference in mean systolic blood pressure, mean diastolic blood pressure, mean arterial blood pressure and mean heart rate between two groups at different times (p value < 0.05). CONCLUSION: The results of this study indicated that dexmedetomidine had higher efficacy, compared to labetalol, in reducing diastolic blood pressure, systolic blood pressure, heart rate, and mean arterial blood pressure following microlaryngoscopy.