Carbamazepine--the commonest cause of toxic epidermal necrolysis and Stevens-Johnson syndrome: a study of 7 years

BACKGROUND

Toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS) are a group of severe life threatening drug reactions. The drugs commonly implicated as the cause of these drug reactions vary depending on host factors and the prescription pattern of drugs in that particular area.

AIM

The aim of the study was to find the drugs implicated as the cause of SJS/TEN in the patients admitted in the dermatology ward at the Medical College, Thrissur and to find the clinical outcome.

METHODS

It was a retrospective study of 7 years from 1997 to 2004. The case records of all patients with a clinical diagnosis of TEN or SJS were studied in detail regarding the drugs implicated as the cause, the management and the clinical outcome.

RESULTS

During the study period, 41 patients in the age group ranging from 12 to 72 years were treated as inpatients, of which 20 were males and 21 were females. The commonest drug implicated as the cause of SJS/TEN was carbamazepine (44%). The indication for carbamazepine was control of pain in more than 50% of the cases. Presence of a major systemic disease before the onset of SJS/TEN was associated with a bad prognosis.

CONCLUSION

The increased use of carbamazepine, especially for control of pain, may be the reason for the increased incidence of SJS/TEN due to the same drug. Awareness about the drugs implicated in life threatening drug reactions will help physicians in preventing them by judicious use of the drugs.

Toxic epidermal necrolysis--a retrospective study

BACKGROUND

Toxic epidermal necrolysis (TEN) is a severe, idiosyncratic, exfoliative disease of the skin and mucous membranes. The treatment of this condition is controversial. High-dose corticosteroid therapy has been the most commonly advocated treatment, but, more recently, this has changed to a no-steroid protocol. These conflicting treatments prompted us to evaluate retrospectively our protocol.

METHODS

The patients admitted to the hospital from 1989 to 1995 with a clinical diagnosis of TEN were included in the study. These patients were given systemic steroids, prophylactic antibiotic, and supportive measures.

RESULTS

The patients belonged to both sexes with an average age of 34 years. The average area of involvement was 85.62%. All the patients made an uneventful recovery without any evidence of sepsis.

CONCLUSIONS

Treatment with systemic steroids is useful in the management of TEN, and there is no need for a burn care center.

Preparation and characterization of pioglitazone cyclodextrin inclusion complexes

Pioglitazone, a class II Biopharmaceutical Classification System drug having poor water solubility and slow dissolution rate may have a negative impact on its subtherapeutic plasma drug levels leading to therapeutic failure. In order to improve its water solubility and thus dissolution, cyclodextrin complexation technique was followed. The phase solubility studies were carried using three different types of cyclodextrins viz., β, methyl-β and γ-cyclodextrins. The Gibbs free energy was calculated in order to determine ease of the complexation. Binary systems of pioglitazone with cyclodextrins were prepared by kneading method and spray drying method. The phase solubility profiles with all the three cyclodextrins were classified as A_L-type, indicating the formation of 1:1 stoichiometric inclusion complexes. The complexation capability of cyclodextrins with pioglitazone increased in the order of methyl-β > β > γ-cyclodextrin. The Gibbs free energy was found to be in the order γ > methyl-β > β cyclodextrin. Characterization of inclusion complexes was done by solubility studies, in vitro dissolution studies, Fourier transformation-infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry and X-ray powder diffractometry studies. Inclusion complexes exhibited higher rates of dissolution than the corresponding physical mixtures and pure drug. Greater solubility was observed with spray-dried methyl-β cyclodextrin complexes (2.29 ± 0.001 mg/ml) in comparison to the kneaded methyl-β cyclodextrin complexes (1.584 ± 0.053 mg/ml) and pure drug (0.0714 ± 0.0018 mg/ml).

Pregnancy and congenital heart disease--maternal and fetal outcome

Two hundred and seventy five pregnancies in patients with congenital heart disease during 1980-1996 were analyzed retrospectively. Maternal and perinatal outcome was compared in 251 pregnancies of women with acyanotic and 24 pregnancies of women with cyanotic heart disease. Congenital heart disease was diagnosed during the index pregnancy in 26.1% of patients and the majority (88.4%) were in NYHA classes 1 and 2. Atrial septal defect (27.7%) was the most common lesion in women with acyanotic heart disease and the majority with cyanotic heart disease had Eisenmenger syndrome, 13 of 21 (61.9%). Sixty pregnancies occurred in patients with surgically corrected lesions (acyanotic, 56; cyanotic, 4). The incidences of abortions (8.3%), stillbirths (13.6%) and small for gestational age (SGA) (36.4%) were higher in cyanotic heart disease compared to acyanotic heart disease (stillbirth, 0.8%; SGA, 6.9%). There was a statistically significant difference in mean maternal age, mean gestational age and mean birth-weight in the surgically corrected and noncorrected lesions in both acyanotic and cyanotic heart disease. There was 1 maternal death in a woman with Eisenmenger syndrome.

Pharmacokinetic profile of a new matrix-type transdermal delivery system: diclofenac diethyl ammonium patch

A transdermal delivery system containing the anti-inflammatory analgesic diclofenac diethyl ammonium in an ethyl hexyl acrylate and vinyl acetate pressure-sensitive adhesive system was developed for percutaneous absorption. These patches were subjected to in vitro permeation and permeation enhancement studies through rat skin using a specially designed diffusion cell. Further, the work deals with percutaneous absorption studies carried out on both animals and human volunteers. The pharmacokinetic parameters calculated from the blood levels of the drug reveal a profile typical of a sustained-release formulation, with the ability to maintain adequate plasma levels for 24 hr (i.e., up to the next application). (Area under the curve [AUC]: 4.356 +/- 1.3 mcg/ml.hr in animals and 0.442 +/- 0.053 mcg/ml.hr in humans; Tmax was 8 hr in both the cases, whereas Cmax was 0.288 +/- 0.088 mcg/ml in animals and 0.034 +/- .008 mcg/ml in human volunteers.) The amount of the drug bioavailable for targeting the sites of action is lower than via the oral route, but the absorbed dose appears to be adequate for therapeutic use, particularly because of the absence of side effects.

Comparative analysis of drought-responsive transcriptomes of sugarcane genotypes with differential tolerance to drought

Water stress causes considerable yield losses in sugarcane. To investigate differentially expressed genes under water stress, two sugarcane genotypes were subjected to three water-deficit levels (mild, moderate, and severe) and subsequent recovery and leaf transcriptome was generated using Illumina NextSeq sequencing. Among the differentially expressed genes, the tolerant genotype Co 06022 generated 2970 unigenes (p ≤ 0.05, functionally known, non-redundant DEGs) at 2-day stress, and there was a progressive decrease in the expressed genes as the stress period increased with 2109 unigenes at 6-day stress and 2307 unigenes at 10-day stress. There was considerable reduction at recovery with 1334 unigenes expressed at 10 days after recovery. However, in the susceptible genotype Co 8021, the number of unigenes expressed at 2 days was lower (2025) than the tolerant genotype and a further reduction was seen at 6-day stress (1552). During recovery, more differentially expressed genes were observed in the susceptible cultivar indicating that the cultivar has to activate more functions/processes to recover from the damage caused by stress. Comparison of DEGs between all stages of stress and recovery in both genotypes revealed that, the commonly up- and down-regulated genes across different stages were approximately double in the tolerant genotype. The most enriched gene ontology classes were heme binding, peroxidase activity and metal ion binding in the biological process and response to oxidative stress, hydrogen peroxide catabolic process and response to stress in the molecular function category. The cellular component was enriched with DEGs involved in extracellular region followed by integral component of membrane. The KEGG pathway analysis revealed important metabolic activities and functionally important genes involved in mitigating water-deficit stress in both the varieties. In addition, several unannotated genes in important pathways were detected and together may provide novel insights into water-deficit tolerance mechanisms in sugarcane. The reliability of the observed expression patterns was confirmed by qRT-PCR. The results of this study will help to identify useful genes for improving drought tolerance in sugarcane.

Yb-fiber-laser-based, 1.8 W average power, picosecond ultraviolet source at 266 nm

We report a compact, stable, high-power, picosecond ultraviolet (UV) source at 266 nm based on simple single-pass two-step fourth-harmonic generation (FHG) of a mode-locked Yb-fiber laser at 79.5 MHz in LiB3O5 (LBO) and β-BaB2O4. Using a 30-mm-long LBO crystal for single-pass second-harmonic generation, we achieve up to 9.1 W of average green power at 532 nm for 16.8 W of Yb-fiber power at a conversion efficiency of 54% in 16.2 ps pulses with a TEM00 spatial profile and passive power stability better than 0.5% rms over 16 h. The generated green radiation is then used for single-pass FHG into the UV, providing as much as 1.8 W of average power at 266 nm under the optimum focusing condition in the presence of spatial walk-off, at an overall FHG conversion efficiency of ∼11%. The generated UV output exhibits passive power stability better than 4.6% rms over 1.5 h and beam pointing stability better than 84 μrad over 1 h. The UV output beam has a circularity of >80% in high beam quality with the TEM00 mode profile. To the best of our knowledge, this is the first report of picosecond UV generation at 266 nm at megahertz repetition rates.

Behavioral neurobiology of inverse agonist FG 7142 induced anxiety syndrome in rats

1. Neurobehavioral survey of inverse agonist FG 7142 was performed employing a novel anxiety paradigm namely FR-2 Two-Way crossover in a shuttle box. 2. FG syndrome was found to be similar to learned helplessness following shock treatment. Significant increase in mean latency to escape was observed from 0 to 25th trial. Effect of FG 7142 on the behavioral and neurological profile did not deviate significantly from controls. However, a general increase in arousal, darting and sideway movement (weaving) of the head were noted. 3. Drugs with specificity at benzodiazepine (BDZ) receptor site were employed as pretreatments in order to study their influence on FG 7142 induced anxiety syndrome. Diazepam and ZK 91296, significantly blocked the inverse agonist response. Head weaving as well as darting movements were completely abolished although rats demonstrated arousal and vigilance. 4. A dose dependent inhibition of FG response was observed with RO 15-1788, a specific BDZ receptor blocker. ZK 93423 at low doses (1 mg/kg) failed to reverse the escape deficit induced by FG. Higher doses of ZK 93423 could not be tested as significant sedation and ataxia were noted. 5. It is suggested that a careful combination of a BDZ agonist and inverse agonist may be beneficial in the treatment of generalised anxiety disorders.

Chemical profiling and α-glucosidase inhibitory activity of essential oils extracted with two methods from some North Western Himalayan aromatic crops

Solvent-free hydrodistillation adsorption apparatus (HDA) and normal clevenger hydrodistillation (NC) were applied to obtain Juniperus communis, Valeriana jatamansi and Hedychium spicatum essential oils (EOs). The yields, chemical compositions and α-glucosidase inhibitory activity of the EOs were investigated. Obtained EOs were analyzed using gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) instruments. Recovery improvement was observed in HDA method (30.4%, 27.3% and 29.0% more recovery of EOs than NC method for V. jatamansi, H. spicatum and J. communis, respectively). Present results demonstrated NCV (V. jatamansi EO (essential oil) by NC method) had highest α-glucosidase inhibitory activity with half-maximal inhibitory concentration (IC₅₀) values of 8.20 μg/mL. As a result, HDA method is considered to be the promising theme for producing EOs with high production recovery. Furthermore, current findings demonstrated that the selected EOs may be a good natural antidiabetic.

Ti:sapphire-pumped deep-infrared femtosecond optical parametric oscillator based on CdSiP2

We report on a femtosecond optical parametric oscillator (OPO) for the deep-infrared (deep-IR) based on the Kerr-lens-mode-locked Ti:sapphire laser as the pump source. By deploying a novel cascaded intracavity arrangement, comprising a femtosecond OPO based on the nonlinear crystal, CdSiP2, synchronously pumped internal to a MgO:PPLN femtosecond OPO, we have generated broadly tunable radiation across 5958-8117 nm using rapid static cavity delay tuning, with a maximum power of 64 μW at 6791 nm, limited by the absorption in mirror substrates as well as polarization-dependent intracavity losses. The deep-IR idler power exhibits excellent passive stability of better than 1.1% rms over 2 h, with a spectral bandwidth as large as ∼650 nm at ∼6800 nm. The demonstrated concept is generic and can be similarly deployed in other operating time scales and wavelength regions, also using different laser pump sources and nonlinear materials.

Identification of novel peptide inhibitors of Plasmodium falciparum dihydrofolate reductase (PfDHFR): molecular docking and MD simulation studies

The presence of drug-resistant variants of Plasmodium parasites within the population has presented a substantial obstacle to the eradication of Malaria. As a result, numerous research groups have directed their efforts towards creating new medication candidates that specifically target parasites. In this study, our main objective was to identify tri-peptide inhibitors for Plasmodium falciparum Dihydrofolate Reductase (PfDHFR) with the aim of finding a new peptide that exhibits superior binding properties compared to the current inhibitor, WR99210. In order to achieve this objective, a virtual library consisting of 8000 tripeptides was generated and subjected to computational screening against wild-type PfDHFR. The purpose of this screening was to discover the most effective binders at the active site. The four most optimal tripeptides identified (Trp-Trp-Glu, Trp-Phe-Tyr, Phe-Trp-Trp, Tyr-Trp-Trp) exhibited significant non-covalent interactions inside the active site of PfDHFR and had binding energies ranging from -9.5 to -9.0 kcal/mol and WR99210 had a binding energy of -6.2 kcal/mol. A 250 ns Molecular Dynamics (MD) simulation was performed to investigate the kinetic and thermodynamic characteristics of the protein-ligand complexes. The Root Mean Square Deviation (RMSD) values for the optimal tripeptides fell within the allowed range, indicating the stability of the ligands inside the protein complex. The Ki value for the most effective tripeptide was 0.3482 µM, whereas WR99210 had a Ki value of 1.02 µM. This article presents the initial discovery of peptide inhibitors targeting PfDHFR. In this text, we provide a comprehensive explanation of the interactions that occur between peptides and the enzyme.

Effect of Foeniculum vulgare Mill. seed extract on the genital organs of male and female rats

Following the oral administration of acetone extract of Foeniculum vulgare (fennel) seeds for 15 days is male rats, total protein concentration was found to be significantly decreased in testes and vas deferens and increased in seminal vesicles and prostate gland. There was a decrease in activities of acid and alkaline phosphatase in all these regions, except that alkaline phosphatase was unchanged in vasa. In female rats, oral administration of the extract for 10 days led to vaginal cornification and oestrus cycle. While moderate doses caused increase in weight of mammary glands, higher doses increased the weight of oviduct, endometrium, myometrium, cervix and vagina also. The results confirm the oestrogenic activity of the seed extract.

Quantitative ultrasonographic evaluation of the carotid arteries in hypertension

Current treatment goals for hypertension include the prevention of end-organ injuries. Hypertension is certainly among the major contributors to atherogenesis, and many antihypertensive drugs seem to have wall-protecting properties. It is critical to identify, test, and implement non-invasive methods for the screening of the population in order to detect early wall abnormalities and to monitor the long-term effects of different antihypertensive treatments. Among these methods, B-mode ultrasound examination of carotid arteries has shown great potential in evaluating treatments that may prevent hypertension-related wall injuries.