Minimum Allergen Screening Panel for Allergic Rhinitis in Bangalore: A Cross Sectional Study.

Allergic rhinitis (AR) is a very common condition presenting to an Otorhinolaryngologist. Prevalence of AR is on the increase and it has significant impact on quality of life of the patient. Skin prick test (SPT) is a simple test to determine allergen sensitization status in patients with AR. There is wide variation in allergen panel used in SPT among various allergy clinics and many centres use a large panel of allergens which requires multiple skin pricks for the patient undergoing the test. Our aim was to identify a minimum panel of allergens among patients with symptoms of AR undergoing SPT which could be used as a screening panel for AR. The present study is a cross sectional study in patients with symptoms of AR undergoing SPT at Allergy clinic of Bangalore Baptist hospital over a period of 18 months from January 2018. 149 patients were included in the study and 26 patients who had negative SPT for all allergens tested were excluded. Prevalence of sensitization for individual allergens was calculated. House dust mite (Dermatophagoides pteronyssinus and Dermatophagoides farinae) was the most prevalent allergen to which 73.9% and 65.8% of our study population was sensitized respectively. We identified a minimum allergen panel of 3 allergens (Dermatophagoides pteronyssinus, Lambs quarter and Dermatophagoides farinae) which could identify > 90% of patients sensitized in the study group.

Usefulness of The Bethesda System of Reporting Thyroid Cytopathology in Surgical Planning.

The Bethesda system for reporting thyroid cytopathology (TBSRTC) has attempted to standardize thyroid fine needle aspiration cytology (FNAC) reporting internationally into six diagnostic categories and help in clinical decision making. But there exists a significant variation in the reporting percentage and rates of malignancies in each category across the centres which complicates clinical decision making. To study the usefulness of TBSRTC in surgical planning of thyroid nodules and to correlate TBSRTC with final histopathology. 85 patients with thyroid nodules who underwent surgery were evaluated prospectively. Preoperatively FNAC and TBSRTC reporting was done and following surgery histopathology was correlated with cytology. Distribution of 85 patients amongst the six categories of TBSRTC was as follows: 2.35% in Category I, 68.23% II, 7.05% III, 16.47% IV, 2.35% V and 3.52% VI. In 93% (79) of patients TBSRTC correlated with histopathology whereas in 7% (6) it did not. Risk of malignancy calculated was 0% in II, 33.33% in III, 7.14% in IV and 100% in V and VI categories. Sensitivity, specificity, Positive Predictive Value and Negative Predictive Value of TBSRTC was 100% for V, VI categories, whereas it was 100%, 78%, 15% and 100% respectively for III, IV. The diagnostic accuracy in our study is 100% for Category V and VI whereas it is 79% for Category III and IV. TBSRTC proved to be a very good screening platform for triaging patients with thyroid nodules into benign and malignant groups, as it is directly related to risk of malignancy in each category. It has helped in appropriate surgical planning in 96.4% of our patients.

Wound healing efficacy of novel ayurveda formulation- Pentabark Kashaya: In wistar rats using excision wound model- an in vivo study.

BACKGROUND: Wound healing plays a major concern in the field of surgery as it requires uneventful healing. Management aims towards prevention of infection and to accelerate healing. Acharya Sushruta has given more emphasis on Vrana (wound) and its chikitsa (treatment). Many antiseptic agents which prevent infection are widely used but have no role in accelerating the healing process and are cytotoxic, deleterious to wound healing. In this regard an innovative polyherbomineral formulation Pentabark Kashaya (PK)was formulated to assess acute dermal toxicity and woundhealing activity. OBJECTIVE: To explore the wound healing efficacy of novel Ayurveda Formulation i.e Pentabark Kashaya in Wistar rats using the excision wound model. MATERIALS AND METHOD: Acute dermal toxicity study was carried out on five female Wistar rats by following the OECD guideline 434 and signs of toxicity were assessed for the period of 14 days. Wound healing activitywas assessed on the excision wound model. 18 male Wistar rats were procured for the study and divided into three groups (n = 6 in each group). The test group was treated with application of PK, standard group with Povidone iodine solution 5% and control group with distilled water. The parameters assessed were epithelialization period, wound contraction rate, wound closure day and swab test for microbial load for the period of 21 days. Statistical analysis was done by using one way ANOVA and Tukeys HSD to assess changes in between three groups at each time point. RESULTS: No signs of acute dermal toxicity were seen, which proved that PK is safe for application. Significant results were seen in the parameters of wound healing like period of epithelialization and wound closure day. Percentage of wound contraction rate was increased in test group when compared to other groups. Histopathology of skin showed marked changes in re-epithelialization, dermal fibroblast, dermal fibrocytes in test group when compared to control group. CONCLUSION: PK is safe for application and it is effective in wound healing. CLINICAL TRIAL REGISTRATION NO: Not applicable.

Comparison of Peres' Formula and Radiological Landmark Formula for Optimal Depth of Insertion of Right Internal Jugular Venous Catheters.

BACKGROUND: Central venous catheterization is a vital procedure for volume resuscitation, infusion of drugs, and for central venous pressure monitoring in the perioperative period and intensive care unit (ICU). It is associated with position-related complications like arrhythmia's, thrombosis, tamponade, etc. Several methods are used to calculate the catheter insertion depth so as to prevent these position-related complications. OBJECTIVE: To compare Peres' formula and radiological landmark formula for central venous catheter insertion depth through right internal jugular vein (IJV) by the anterior approach. MATERIALS AND METHODS: A total of 102 patients posted for elective cardiac surgery were selected and divided into two equal groups-Peres' group (group P) and radiological landmark group (group R). Central venous catheterization of right IJV was done under ultrasound (USG) guidance. In group P, central venous catheter insertion depth was calculated as height (cm)/10. In group R, central venous catheter insertion depth was calculated by adding the distances from the puncture point to the right sternoclavicular joint and on chest X-ray the distance from the right sternoclavicular joint to carina. After insertion, the catheter tip position was confirmed using transesophageal echocardiography (TEE) in both the groups. RESULTS: About 49% of the catheters in group P and 74.5% in group R were positioned optimally as confirmed by TEE, which was statistically significant. No complications were observed in both the groups. CONCLUSION: Radiological landmark formula is superior to Peres' formula for measuring optimal depth of insertion of right internal jugular venous catheter. HOW TO CITE THIS ARTICLE: Manudeep AR, Manjula BP, Dinesh Kumar US. Comparison of Peres' Formula and Radiological Landmark Formula for Optimal Depth of Insertion of Right Internal Jugular Venous Catheters. Indian J Crit Care Med 2020; 24(7):527-530.

Biological applications of microchip electrophoresis with amperometric detection: in vivo monitoring and cell analysis.

Microchip electrophoresis with amperometric detection (ME-EC) is a useful tool for the determination of redox active compounds in complex biological samples. In this review, a brief background on the principles of ME-EC is provided, including substrate types, electrode materials, and electrode configurations. Several different detection approaches are described, including dual-channel systems for dual-electrode detection and electrochemistry coupled with fluorescence and chemiluminescence. The application of ME-EC to the determination of catecholamines, adenosine and its metabolites, and reactive nitrogen and oxygen species in microdialysis samples and cell lysates is also detailed. Lastly, approaches for coupling of ME-EC with microdialysis sampling to create separation-based sensors that can be used for near real-time monitoring of drug metabolism and neurotransmitters in freely roaming animals are provided. Graphical abstract.

Parental-Group Interventions for Parents of Children with Mental Health Problems Admitted in a Tertiary Care Center: An Experience from India.

BACKGROUND: Families play a critical role in their children's development and learning. Parents' understanding of their child's illness has a significant impact on the parent-child relationship and helps them to have realistic expectations. OBJECTIVES: The objective of this study is to understand the use of parental-group intervention for making parents understand the problems of the children and to develop skills to deal with the problems. METHODS: A six-session parental-group intervention module was developed and tested. Data from the group session were collected for 6 months and have been analyzed. RESULTS: Majority of the parents appreciated the intervention program as it led to skill-building and understanding of the mental health problems among children. Demonstration was liked most of the parents (74) parenting skills and stress management (71 parents); 68 parents liked session on school-related issues; 60 parents liked session on developmental disorders; 54 parents liked session on emotional and behavioral problems. CONCLUSION: Group-based parenting programs are found to be effective in improving the overall psychosocial health of parents and the emotional and behavioral problems of children and adolescents as a result of better parenting.

Evaluation of dual electrode configurations for microchip electrophoresis used for voltammetric characterization of electroactive species.

Microchip electrophoresis coupled with amperometric detection is more popular than voltammetric detection due to the lower limits of detection that can be achieved. However, voltammetry provides additional information about the redox properties of the analyte that can be used for peak identification. In this paper, two dual electrode configurations for microchip electrophoresis are described and evaluated for obtaining voltammetric information using amperometry. The dual-series electrode configuration was first evaluated to generate current ratios in a single run by applying two different potentials to the working electrodes placed perpendicular to the separation channel. However, it was found that it is difficult to obtain realistic current ratios with this configuration, primarily due to the relative placement of electrodes with respect to the channel end of the simple-t microchip. Correction factors were needed to obtain current ratios similar to those that would be obtained for sequential injections at two different potentials using a single electrode. A second approach using a dual-channel chip with two parallel electrodes was then developed and evaluated for obtaining voltammetric identification. The newly developed microchip permitted the injection of same amount of sample into two unique separation channels, each with an electrode at a different detection potential. Migration times and current ratios for several biologically important molecules and potential interferences including nitrite, tyrosine, hydrogen peroxide, and azide were obtained and compared to the responses obtained for analytes found in macrophage cell lysates.

Optimization of a microchip electrophoresis method with electrochemical detection for the determination of nitrite in macrophage cells as an indicator of nitric oxide production.

Nitric oxide (NO) is involved in many biological functions, including blood pressure regulation, the immune response, and neurotransmission. However, excess production of NO can lead to the generation of reactive nitrogen species and nitrosative stress and has been linked to several neurodegenerative diseases and cardiovascular disorders. Because NO is short-lived and generally difficult to detect, its primary stable degradation product, nitrite, is frequently monitored in its place. In this paper, an improved method using microchip electrophoresis with electrochemical detection (ME-EC) was developed for the separation and detection of nitrite in cell lysates. A separation of nitrite from several electroactive cell constituents and interferences was optimized, and the effect of sample and buffer conductivity on peak efficiency was explored. It was found that the addition of 10 mM NaCl to the run buffer caused stacking of the nitrite peak and improved limits of detection. A platinum black working electrode was also evaluated for the detection of nitrite and other electroactive cellular species after electrophoretic separation. The use of a modified platinum working electrode resulted in 2.5-, 1.7-, and 7.2-fold signal enhancement for nitrite, ascorbic acid, and hydrogen peroxide, respectively, and increased the sensitivity of the method for nitrite twofold. The optimized ME-EC method was used to compare nitrite production by native and lipopolysaccharide-stimulated RAW 264.7 macrophage cells.

Fiberoptic Endoscopic Evaluation of Swallow (FEES) in Intensive Care Unit Patients Post Extubation.

Intensive care unit patients frequently require prolonged intubation and ventilator support. Swallowing dysfunction often occurs in patients who receive prolonged mechanical ventilation. Intubation can cause transient injury to the larynx with a subsequent reduction in protective mechanism and increased incidence of oropharyngeal secretions once patient is extubated. Aim of this study was to evaluate the anatomical damage caused by intubation and the occurrence of aspiration/silent aspiration in patients following extubation, using fiberoptic endoscopic evaluation of swallow (FEES) as diagnostic and therapeutic tool. Participants in the study included all adult ICU patients who were intubated for ≥ 48 h. Head injury patients, patients with abnormal neurological status, completely disoriented patients were excluded. We performed FEES in 41 patients. Duration of intubation was in the range of 2-9 days. We studied 41 patients, among them 19(44%) patients had laryngeal injury and 6 (14%) had aspiration. we noticed that all patients who had aspiration had some laryngeal injury. All 6 patients who had aspiration initially recovered their swallowing function fully as noticed during repeat FEES done after swallow therapy. There is a significant impact of intubation on occurrence of aspiration (14%) and laryngeal abnormality (44%). We found in our study that there is a significant correlation to duration of intubation and occurrence of laryngeal injury.

Non-toxic engineered carbon nanodiamond concentrations induce oxidative/nitrosative stress, imbalance of energy metabolism, and mitochondrial dysfunction in microglial and alveolar basal epithelial cells.

Engineered nanoparticles are finding a wide spectrum of biomedical applications, including drug delivery and capacity to trigger cytotoxic phenomena, potentially useful against tumor cells. The full understanding of their biosafety and interactions with cell processes is mandatory. Using microglial (BV-2) and alveolar basal epithelial (A549) cells, in this study we determined the effects of engineered carbon nanodiamonds (ECNs) on cell viability, nitric oxide (NO) and reactive oxygen species (ROS) production, as well as on energy metabolism. Particularly, we initially measured decrease in cell viability as a function of increasing ECNs doses, finding similar cytotoxic ECN effects in the two cell lines. Subsequently, using apparently non-cytotoxic ECN concentrations (2 µg/mL causing decrease in cell number < 5%) we determined NO and ROS production, and measured the concentrations of compounds related to energy metabolism, mitochondrial functions, oxido-reductive reactions, and antioxidant defences. We found that in both cell lines non-cytotoxic ECN concentrations increased NO and ROS production with sustained oxidative/nitrosative stress, and caused energy metabolism imbalance (decrease in high energy phosphates and nicotinic coenzymes) and mitochondrial malfunctioning (decrease in ATP/ADP ratio).These results underline the importance to deeply investigate the molecular and biochemical changes occurring upon the interaction of ECNs (and nanoparticles in general) with living cells, even at apparently non-toxic concentration. Since the use of ECNs in biomedical field is attracting increasing attention the complete evaluation of their biosafety, toxicity and/or possible side effects both in vitro and in vivo is mandatory before these highly promising tools might find the correct application.

Microchip electrophoresis with laser-induced fluorescence detection for the determination of the ratio of nitric oxide to superoxide production in macrophages during inflammation.

It is well known that excessive production of reactive oxygen and nitrogen species is linked to the development of oxidative stress-driven disorders. In particular, nitric oxide (NO) and superoxide (O2•-) play critical roles in many physiological and pathological processes. This article reports the use of 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate and MitoSOX Red in conjunction with microchip electrophoresis and laser-induced fluorescence detection for the simultaneous detection of NO and O2•- in RAW 264.7 macrophage cell lysates following different stimulation procedures. Cell stimulations were performed in the presence and absence of cytosolic (diethyldithiocarbamate) and mitochondrial (2-methoxyestradiol) superoxide dismutase (SOD) inhibitors. The NO/O2•- ratios in macrophage cell lysates under physiological and proinflammatory conditions were determined. The NO/O2•- ratios were 0.60 ± 0.07 for unstimulated cells pretreated with SOD inhibitors, 1.08 ± 0.06 for unstimulated cells in the absence of SOD inhibitors, and 3.14 ± 0.13 for stimulated cells. The effect of carnosine (antioxidant) or Ca2+ (intracellular messenger) on the NO/O2•- ratio was also investigated. Graphical Abstract Simultaneous detection of nitric oxide and superoxide in macrophage cell lysates.

Carnosine modulates nitric oxide in stimulated murine RAW 264.7 macrophages.

Excess nitric oxide (NO) production occurs in several pathological states, including neurodegeneration, ischemia, and inflammation, and is generally accompanied by increased oxidative/nitrosative stress. Carnosine [ß-alanine-histidine (ß-Ala-His)] has been reported to decrease oxidative/nitrosative stress-associated cell damage by reducing the amount of NO produced. In this study, we evaluated the effect of carnosine on NO production by murine RAW 264.7 macrophages stimulated with lipopolysaccharides + interferon-γ. Intracellular NO and intracellular and extracellular nitrite were measured by microchip electrophoresis with laser-induced fluorescence and by the Griess assay, respectively. Results showed that carnosine causes an apparent suppression of total NO production by stimulated macrophages accompanied by an unexpected simultaneous drastic increase in its intracellular low toxicity endproduct, nitrite, with no inhibition of inducible nitric oxide synthase (iNOS). ESI-MS and NMR spectroscopy in a cell-free system showed the formation of multiple adducts (at different ratios) of carnosine-NO and carnosine-nitrite, involving both constituent amino acids (ß-Ala and His) of carnosine, thus providing a possible mechanism for the changes in free NO and nitrite in the presence of carnosine. In stimulated macrophages, the addition of carnosine was also characterized by changes in the expression of macrophage activation markers and a decrease in the release of IL-6, suggesting that carnosine might alter M1/M2 macrophage ratio. These results provide evidence for previously unknown properties of carnosine that modulate the NO/nitrite ratio of stimulated macrophages. This modulation is also accompanied by changes in the release of pro-inflammatory molecules, and does not involve the inhibition of iNOS activity.

5-Fluorouracil Loaded Chitosan-PVA/Na+MMT Nanocomposite Films for Drug Release and Antimicrobial Activity.

In the present study, chitosan and polyvinyl alcohol (PVA) were blended with different concentrations of sodium montmorillonite (Na+MMT) clay solution by a solvent casting method. X-ray diffraction and transition electron microscope results show that the film properties are related to the co-existence of Na+MMT intercalation/exfoliation in the blend and the interaction between chitosan-PVA and Na+MMT. 5-Fluorouracil (5-FU) was loaded with chitosan-PVA/Na+MMT nanocomposite films for in vitro drug delivery study. The antimicrobial activity of the chitosan-PVA/Na+MMT films showed significant effect against Salmonella (Gram-negative) and Staphylococcus aureus (Gram-positive), whereas 5-FU encapsulated chitosan-PVA/Na+MMT bio-nanocomposite films did not show any inhibition against bacteria. Our results indicate that combination of a flexible and soft polymeric material with high drug loading ability of a hard inorganic porous material can produce improved control over degradation and drug release. It will be an economically viable method for preparation of advanced drug delivery vehicles and biodegradable implants or scaffolds.

A comparative study of intravenous paracetamol and intravenous tramadol for postoperative analgesia in laparotomies.

BACKGROUND: Pain in the perioperative setting or thereafter plays a significant role in delaying an otherwise successful recovery. Hence, mitigation of such postoperative pain assumes importance. Among the various agents employed for such mitigation, opioids and non-steroidal anti-inflammatory drugs have for some time taken center stage. However, alas they are not without their share of adverse effects. This study was undertaken with the purpose of elucidating the efficacy of intravenous (IV) paracetamol as compared to IV tramadol in mitigating postoperative pain while observing its effect on hemodynamic stability and the presence of adverse drug reactions, if any. MATERIALS AND METHODS: A total of 60 randomized cases aged ranges from 20 to 60 years of both sexes divided into two groups (each for paracetamol and tramadol) scheduled for laparotomies were administered IV paracetamol and tramadol for postoperative pain relief and assessed with visual analog scale (VAS) score and variations in vital parameters to ascertain extent of pain relief and post-operative nausea vomiting (PONV). RESULTS: Data so collected was statistically interpreted, and observations extrapolated. Save for a perceptible decline in PONV with paracetamol group compared with tramadol group with a statistically significant P < 0.001, nothing statistically significant was observed in any other parameter, including VAS scores between either group. CONCLUSION: IV paracetamol is a safer alternative to tramadol with lesser PONV in the postoperative period translates into the lesser duration of hospitalization and hence earlier discharge.

Influence of alkali metal cations on the thermal, mechanical and morphological properties of rectorite/chitosan bio-nanocomposite films.

The main theme of this work is to study the influence of ion-exchangeable alkali metal cations, such as: Li(+), Na(+), K(+), and Cs(+) on the thermal, mechanical and morphological properties. In this regard, a set of rectorite/chitosan (REC-CS) bio-nanocomposite films (BNCFs) was prepared by facile reaction of chitosan with ion-exchanged REC clay. The microstructure and morphology of BNCFs were investigated with XRD, TEM, SEM and AFM. Thermal and tensile properties of BNCFs were also investigated. As revealed from TEM and XRD results, the BNCFs featured a mixed morphology. Some intercalated clay sheets, together with nano-sized clay tactoids were obtained in LiREC/CS, NaREC/CS and KREC/CS of the BNCFs. From fractured surface study, via SEM, it was observed that the dispersion of chitosan polymer attaches to (and covers) the clay platelets. FTIR confirmed strong hydrogen bonds between clay and chitosan polymer. In addition, the thermal stabilities significantly varied when alkali metal cations varied from Li(+) to Cs(+). The BNCFs featured high tensile strengths (up to 84 MPa) and tensile moduli (up to 45 GPa). After evaluating these properties of BNCFs, we came to conclusion that these bio-nano composites can be used for packaging applications.

Prognostic and predictive factors in gingivo buccal complex squamous cell carcinoma: role of tumor budding and pattern of invasion.

Invasive tumor front (ITF) is the deepest three to six cell layers or detached tumor cell groups at the advancing edge of the tumor. Tumor budding is defined as presence of isolated single cells or small cell clusters scattered in the stroma ahead of the ITF and is characteristic of aggressive cancer. It is recognized as an adverse prognostic factor in several human cancers like colorectal, oesophageal, laryngeal cancers and more recently tongue cancers. However, the prognostic value of tumor budding has not been reported in GBCSCC. The aim of our study was to evaluate the role of pattern of invasion (POI) at the ITF, Tumor budding and other clinicopathological parameters in predicting nodal metastases and prognosis in GBCSCC. 33 patients with primary GBCSCC were prospectively evaluated at a tertiary care referral centre. Tumor budding and type of POI was examined in detail and data documented. Statistical analyses were carried out to assess the correlation of tumor budding, POI, and other clinicopathologic parameters (stage, grade of the tumor, tumor thickness, PNI, LVI) with nodal metastases and predict prognosis. Cox regression was used for both Univariate and multivariate analysis. Significant predictors of nodal metastases on Univariate analysis were male gender (p = 0.021), smoking (p = 0.046), Tumor budding (p = 0.014) and diffuse infiltrative/worst POI (p = 0.004), where as on multivariate analysis only worst POI was significantly associated with positive lymph nodes (p = 0.004). Presence of nodal metastases (p = 0.01) and tumor thickness >5 mm (p = 0.009) were independent negative prognostic factors on multivariate analysis. Significant single risk factor predictive of positive lymph nodes is worst POI in GBCSCC. Nodal metastases and >5 mm tumor thickness are independent risk factors for disease free survival.

Labour induction with an intermediate-dose oxytocin regimen has advantages over a high-dose regimen.

A total of 200 women planned for labour induction were randomised to receive high-dose oxytocin (6 mU/min with similar increments every 45 min) or intermediate-dose oxytocin (3 mU/min with similar increments every 45 min). Oxytocin solution was prepared with 30 units in 500 ml saline with which the infusion rate in ml/h is numerically equal to oxytocin in mU/min. We observed that the caesarean rate (18% vs 6%, p = 0.009), contraction abnormalities (35% vs 14%, p = 0.0005) and neonatal bilirubin levels (7.99 ± 2.70 vs 6.80 ± 2.65, p = 0.002) were higher with high-dose than with intermediate-dose. The induction-delivery interval (IDI) was similar (10 h 13 min with high-dose and 11 h 5 min with intermediate-dose; p = 0.237, NS). Nulliparous women benefited more with intermediate-dose as the caesarean rate was higher with high-dose (24.6% vs 7.9%, p = 0.011). Although the caesarean rate was higher in multiparous women with high-dose oxytocin, it was statistically not significant (5.7% vs 2.7%; p = 0.609). Oxytocin regimens for labour induction are usually high-dose (4-6 mU/min) or low-dose (1-1.5 mU/min). The former is associated with more contraction abnormalities and the latter with prolonged IDI; both result in an increased caesarean rate. In order to offset these disadvantages, an intermediate- dose regimen was selected. The increment interval of 45 min was selected in accordance with the pharmacokinetics of oxytocin. We observed a lower caesarean rate when compared with the high-dose regimen, without any increase in the IDI. Hence, we propose that the intermediate-dose oxytocin regimen should be preferred to the high-dose regimen for labour induction.

Determination of heterogeneous electron transfer and homogeneous comproportionation rate constants of tetracyanoquinodimethane using scanning electrochemical microscopy.

We report the use of scanning electrochemical microscopy (SECM) in determining the heterogeneous electron transfer and homogeneous comproportionation kinetics of tetracyanoquinodimethane (TCNQ) in acetonitrile at Pt tip UMEs (radius 12.5­1 µm). TCNQ undergoes two consecutive one-electron reductions with comproportionation occurring between TCNQ2­, the product of the second reduction, and bulk TCNQ to produce TCNQ­. A standard rate constant, k(1)(0) = 2.9 ± 0.5 cm/s, for the first reduction was determined by tip voltammetry with total positive feedback and a large Pt substrate. A comparatively smaller rate constant, k(2)(0) = 0.44 ± 0.05 cm/s, for the second reduction was determined in the absence of comproportionation by tip voltammetry with the tip shielded from the bulk TCNQ solution by the TCNQ­ diffusion layer of the large Pt substrate. A comproportionation rate constant, k(comp) = 1 × 10(6) M(­1) s(­1), was determined by tip pulse chronoamperometry at coaxially aligned tip and substrate UMEs of the same radius. Diffusion coefficients of the TCNQ species and standard potentials for the reductions were also determined. Experimental results were compared with 2D transient axisymmetric simulations and reported analytical equations.

Reconstruction of large composite buccal defects using single soft tissue flap--analysis of functional outcome.

Resection of advanced gingivo-buccal tumors results in a posterolateral mandibular and large soft tissue defect. Because of large soft tissue requirement, these defects are difficult to reconstruct using a single osteocutaneous flap. A double free flap reconstruction of such defects is recommended. However, double flap may not be feasible in certain situations. In this study, we objectively evaluated functional and cosmetic outcomes following single soft-tissue flap reconstruction in a group of patients where double flap reconstruction was not feasible. Patient and defect characteristics were obtained from charts. The speech and swallowing functions of patients were prospectively assessed by a dedicated therapist. The cosmetic outcome of reconstruction was evaluated by an independent observer. Fifty-six patients with large soft tissue and segmental posterolateral mandible defect, reconstructed with anterolateral thigh or pectoralis major flap from May 2009 till December 2010 were included. In this series, none of the flaps were lost; two patients with pectoralis major flap developed partial skin paddle loss. Most of the patients developed mandibular drift; however, majority of these patients had no postoperative trismus. All patients resumed regular or soft solid oral diet. The mean speech intelligibility was more than 70%. Majority of patients had satisfactory cosmetic outcome. The defects were classified into regions resected to develop a reconstruction algorithm for optimal reconstruction using a free or pedicle flap. In conclusion, patients with large oro-mandibular defect undergoing single soft tissue flap reconstruction have satisfactory functional and cosmetic outcome.

Anaesthetic management of two different cases of mediastinal mass.

We report the management of two paediatric cases undergoing median sternotomy and right lateral thoracotomy for mediastinal mass. An 8-year-old boy presented with a history of intermittent fever and episodes of respiratory illness since 3 years and a 16-year-old girl presented with dyspnoea, cough, fever and dysphagia for solid foods. Radiological investigation confirmed the diagnoses. Absence of pressure symptoms pointed towards a compressible mass in the boy and indicated a non-compressible mass in the girl. We discuss the anaesthetic management of the younger patient with an uneventful course as opposed to the older patient where airway obstruction ensued soon after induction and led to near-cardiopulmonary arrest necessitating rescue measures. Swift measures at securing airway while simultaneously resuscitating the patient served to successfully revert an otherwise fateful eventuality.