Jumping in lantern bugs (Hemiptera, Fulgoridae).

Lantern bugs are amongst the largest of the jumping hemipteran bugs, with body lengths reaching 44 mm and masses reaching 0.7 g. They are up to 600 times heavier than smaller hemipterans that jump powerfully using catapult mechanisms to store energy. Does a similar mechanism also propel jumping in these much larger insects? The jumping performance of two species of lantern bugs (Hemiptera, Auchenorrhyncha, family Fulgoridae) from India and Malaysia was therefore analysed from high-speed videos. The kinematics showed that jumps were propelled by rapid and synchronous movements of both hind legs, with their trochantera moving first. The hind legs were 20-40% longer than the front legs, which was attributable to longer tibiae. It took 5-6 ms to accelerate to take-off velocities reaching 4.65 m s-1 in the best jumps by female Kalidasa lanata. During these jumps, adults experienced an acceleration of 77 g, required an energy expenditure of 4800 µJ and a power output of 900 mW, and exerted a force of 400 mN. The required power output of the thoracic jumping muscles was 21,000 W kg-1, 40 times greater than the maximum active contractile limit of muscle. Such a jumping performance therefore required a power amplification mechanism with energy storage in advance of the movement, as in their smaller relatives. These large lantern bugs are near isometrically scaled-up versions of their smaller relatives, still achieve comparable, if not higher, take-off velocities, and outperform other large jumping insects such as grasshoppers.

Wing rotation and the aerodynamic basis of insect flight.

The enhanced aerodynamic performance of insects results from an interaction of three distinct yet interactive mechanisms: delayed stall, rotational circulation, and wake capture. Delayed stall functions during the translational portions of the stroke, when the wings sweep through the air with a large angle of attack. In contrast, rotational circulation and wake capture generate aerodynamic forces during stroke reversals, when the wings rapidly rotate and change direction. In addition to contributing to the lift required to keep an insect aloft, these two rotational mechanisms provide a potent means by which the animal can modulate the direction and magnitude of flight forces during steering maneuvers. A comprehensive theory incorporating both translational and rotational mechanisms may explain the diverse patterns of wing motion displayed by different species of insects.

A Comparison of Clinical Features, Pathology and Outcomes in Various Subtypes of Breast Cancer in Indian Women.

BACKGROUND: Breast cancer is often classified into subtypes using immunohistochemical markers. These subtypes have distinct biological behaviour. This study was conducted with the aim of estimating the distribution of various subtypes of breast cancer in Indian population based on immunohistochemistry markers and to determine the clinical features, pathology and outcomes of these subtypes of breast cancer. MATERIALS AND METHODS: A retrospective study was undertaken and all patients of breast cancer over a 5 year period were included. These patients were divided into 4 subgroups depending on the presence or absence of immunohistochemical markers: i) Luminal A (ER/PR+, Her 2 neu-); ii) Luminal B (ER/PR+, Her 2 neu+); iii) Her 2 enriched (ER-/PR-, Her 2 neu+) and; iv) Triple negative (ER-, PR-, Her2 neu-). Clinical and pathological features and survival were compared between patients in the 4 subgroups. RESULTS: Luminal A subgroup had majority of patients (43.8%). Patients in Luminal B, Her 2 enriched, and Triple negative subgroups were 14.8%, 16.1% and 25.3%. Median follow-up of patients was for 34 months. Luminal A subgroup patients were more likely to be postmenopausal and have smaller and lower grade (I/II) tumours with better survival (OS-91.06%). Patients in the Triple negative subgroup were more likely to be premenopausal (p-value 0.036, odds ratio 0.611, CI 0.394-0.949), have larger and higher grade (III) tumours with worse overall survival (OS-88.46%, odds ratio 1.32, 95%CI 0.602-2.39). Her 2 enriched group patients had bad prognostic features like larger size of tumour and higher grade of tumour and worst survival among all the subgroups (OS-85.07%, odds ratio 1.78, 95% CI 0.767-4.163). However, these outcomes were not statistically significant for the subgroups. CONCLUSION: A retrospective study was undertaken of breast cancer patients in India, according to subtypes based on immunohistochemistry. Luminal A had prognostic features and survival which was better as compared to other subgroups (Luminal B, Her 2 enriched and Triple negative). Incidence of patients with Triple negative breast cancer was higher in the premenopausal period. Patients with Her 2 enriched breast cancer had the worst survival among all the subgroups.

A randomized, double-blind, parallel-group, comparative safety, and efficacy trial of oral co-artemether versus oral chloroquine in the treatment of acute uncomplicated Plasmodium falciparum malaria in adults in India.

In India, treatment of acute, uncomplicated Plasmodium falciparum malaria is becoming increasingly difficult due to resistance to chloroquine, thus there is a need for new antimalarial drugs. CGP 56697 (co-artemether), a new drug, is a combination of artemether and lumefantrine in a single oral formulation (one tablet = 20 mg of artemether plus 120 mg of lumefantrine). In a double-blind study, 179 patients with acute uncomplicated P. falciparum malaria were randomly assigned to receive either CGP (n = 89) given as a short course of 4 x 4 tablets over a 48-hr period or chloroquine (n = 90) given as four tablets (one tablet = 150 mg of chloroquine base) initially, followed by two tablets each at 6-8, 24, and 48 hr. Due to a death in the chloroquine group and a decrease in the chloroquine cure rate to < 50% (based on the blinded overall cure rate at that time), recruitment was terminated prematurely. CGP 56697 showed a superior 28-day cure rate (95.4% versus 19.7%; P < 0.001), time to parasite clearance (median = 36 versus 60 hr; P < 0.001), and resolution of fever (median = 18 versus 27 hr; P = 0.0456). This drug provides a safe, effective, and rapid therapy for the treatment of acute uncomplicated P. falciparum malaria.

A multi-centre comparative study of diclofenac sodium and a dipyrone/spasmolytic combination, and a single-centre comparative study of diclofenac sodium and pethidine in renal colic patients in India.

A single-blind, randomized clinical trial was carried out to compare the analgesic effectiveness in patients with renal colic of single intramuscular doses of diclofenac sodium (75 mg) versus a dipyrone (1 g)/spasmolytics combination, and diclofenac sodium (75 mg) versus pethidine (75 mg). The first study involved three centres, the second study one centre. In total, 107 patients were treated with diclofenac sodium, 85 with dipyrone/spasmolytics, and 25 with pethidine. Assessments were made during the first hour after drug administration of the degree of pain relief, the severity of pain using a visual analogue scale, and the duration of analgesia. A global assessment of treatment efficacy was made by the participating physicians at the end of the study period. Patients treated with diclofenac sodium showed an earlier onset of analgesia and a higher incidence of total pain relief compared to those treated with dipyrone/spasmolytics or pethidine. Although the mean duration of analgesia was only slightly greater in the diclofenac sodium group than in the dipyrone/spasmolytics group, a significantly longer effect was seen when diclofenac sodium was compared with pethidine (p less than 0.01). Pain severity assessments revealed that diclofenac sodium caused a significantly greater improvement in pain after 60 minutes compared to dipyrone/spasmolytics (p less than 0.05) and after 30 minutes compared to pethidine (p less than 0.05). Global efficacy assessments by the physician rated diclofenac sodium as significantly superior to dipyrone/spasmolytics (p less than 0.01) and pethidine (p less than 0.001). Moreover, diclofenac sodium was better tolerated than either of the comparative treatments. The results indicate that intramuscular diclofenac sodium is a useful alternative to the drugs commonly used in India in the treatment of renal colic.

Comparative effect of dimethindene maleate and chlorpheniramine maleate on histamine-induced weal and flare.

Antihistaminic activity of 3 or 6 mg dimethindene maleate was compared with that of placebo and 12 mg chlorpheniramine maleate in 60 healthy volunteers in a randomized, crossover study. Activity of each drug was assessed by measuring 2 micrograms histamine-induced weal and flare areas. Compared with placebo, both doses of dimethindene and chlorpheniramine significantly (P less than 0.001) reduced weal area. Both doses of dimethindene (P less than 0.001) and chlorpheniramine (P less than 0.05) also significantly reduced flare area. Dimethindene (6 mg) brought about the maximum reduction in weal area (28.8%) and flare area (39.1%). Dimethindene (6 mg) also reduced weal area significantly (P less than 0.01) compared with chlorpheniramine and reduced flare area significantly (P less than 0.05) compared with 3 mg dimethindene. Using a 100 mm visual analogue scale for assessment of weal and flare intensities, 6 mg dimethindene again produced the maximum response. The study confirmed that the antihistamine activity of dimethindene was better than that of chlorpheniramine.

Stevens-Johnson syndrome and toxic epidermal necrolysis-challenges of recognition and management.

Skin adverse drug reactions (ADRs) generally present as transient erythematous macular/papular rashes. However these can many a times be the initial presentation of serious muco-cutaneous ADRs such as Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN). The incidence of SJS varies from 1.2 to 6 per million patient-years and that of TEN to be 0.4 to 1.2 per million patient-years. The pathophysiological mechanism of SJS and TEN have not been fully elucidated. The aetiological factors of SJS and TEN are diverse; drugs being the cause in more than 80% cases of TEN and about 40-50% cases of SJS. Mucous membranes are affected in nearly all cases. The extent of epidermal sloughing may vary and forms a basis for the classification of an individual case as SJS or TEN. Prognosis of SJS is better than that of TEN; mortality rates being about 5% and 30%-40% respectively. Specific therapy for these conditions is yet not available. The use of systemic corticosteroids has been controversial. Early diagnoses can prevent/reduce the morbidity of such serious ADRs. This article provides a brief review of the clinical presentation and management of SJS and TEN.

Patterns of rheumatic diseases and antirheumatic drug usage in 11931 Indian patients.

Patterns of rheumatic diseases and antirheumatic drug usage in different regions of India were analysed. The data was collected from a post-marketing surveillance of diclofenac sodium (Voveran) in 11931 patients. The common conditions were-rheumatoid arthritis (RA) 28.1%, osteoarthrosis (OA) 24.8%, soft-tissue rheumatism 12.4%, cervical spondylosis 6%, ankylosing spondylitis (AS) 3.5%, gout 2%. East zone had a significantly lower proportion of osteoarthritis (20.9%). The age distribution and sex ratios of RA, OA and AS were in line with literature reports. The severity of illness was moderate in 62% and duration was more than 6 months in 50.2%. Data on NSAID usage showed a preponderance of combinations and ibuprofen. There were no significant differences in NSAID usage across diseases or regions.

Comparative bioavailability study of clonazepam after oral administration of two tablet formulations.

OBJECTIVE: To assess the bioavailability of clonazepam from two brands of 2 mg tablet formulations--Epitril and reference brand. METHODS: A two-way randomised cross-over bioavailability study was carried out in 12 healthy male volunteers. Coded plasma samples were analysed for levels of clonazepam by high performance liquid chromatography (HPLC) method. RESULTS: The mean Cmax, Tmax t1/2 beta and AUC (0-48) for Epitril were: 16.31 +/- 3.07 ng/mL, 1.63 +/- 0.48 h, 46.97 +/- 12.26 h and 207.70 +/- 57.07 ng/ml.h; for reference brand were 19.75 +/- 5.95 ng/mL, 1.42 +/- 0.29 h, 46.88 +/- 11.29 h and 215.70 +/- 50.89 ng/ml.h respectively. These were comparable and the differences were not statistically significant. CONCLUSION: Based on above pharmacokinetic parameters, Epitril was bioequivalent to reference brand.

Comparison of absorption rate and bioavailability of two brands of carbamazepine.

OBJECTIVE: To assess the bioavailability of carbamazepine from two brands of carbamazepine--Tegretol 200 and Zen-200. METHODS: A two-way randomised cross-over bioavailability of carbamazepine was carried out in twelve healthy male volunteers. Coded plasma samples were analysed for levels of carbamazepine by high performance liquid chromatography (HPLC) method. Tegretol 200 and Zen-200 were tested for in-vitro dissolution profiles. RESULTS: The mean Cmax, Tmax and t1/2a for Tegretol 200 were: 2.17 +/- 0.42 mcg/mL, 11.67 +/- 6.37 h and 2.72 +/- 1.87 h; for Zen-200 were 3.10 +/- 0.05 mcg/mL, 3.50 +/- 2.11 h and 0.76 +/- 0.76 h respectively. These values were statistically significant. However AUC (0-96 h) value of 150.16 +/- 27.13 mcg/ml.h after Zen-200 was not statistically significant as compared to 128.68 +/- 20.22 mcg/ml.h after Tegretol 200. The in-vitro dissolution profiles of the two formulations were dissimilar. The fluctuations in CBZ levels after Tegretol 200 was significantly less as compared to Zen-200. The absorption profile as judged by parameter 'A' was 50.44 +/- 10.95 for Tegretol 200 and 42.49 +/- 18.89 for Zen-200. CONCLUSION: Based on parameter 'A' and other pharmacokinetic parameters, the marketed generic carbamazepine product, Zen-200 is not bioequivalent to Tegretol 200.

Comparative bioavailability study of a conventional and two controlled release oral formulations of Tegretol (carbamazepine)--200 mg.

OBJECTIVES: To assess the bioquivalence of carbamazepine (CBZ) controlled release formulation A (Tegretol CR, local) vs formulation B (Tegretol CR, Basel) and confirm their controlled release characteristics by comparing with conventional formulation (Tegretol). METHODS: A three-way randomized cross-over bioavailability study was carried out using CBZ 200 mg tablets of conventional and two controlled release formulations in twelve healthy volunteers. Coded plasma samples were analysed for levels of CBZ by HPLC method. RESULTS: The mean Cmax, Tmax, t1/2 and AUC for formulation A were: 1.67 +/- 0.26 mcg/mL, 24 +/- 0 hr, 47.8 +/- 9.7 hr and 136.7 +/- 25.4 mcg/ml. h; for formulation B were 1.41 +/- 0.31 mcg/mL, 25 +/- 8 hr, 46.9 +/- 7.9 and 119 +/- 32.3 mcg/ml.h and for conventional formulation were 2.43 +/- 3.6 mcg/mL, 9.5 +/- 7.4 hr, 44.6 +/- 9.8 hr and 178.8 +/- 41.9 mcg/ml.h respectively. The fluctuation in plasma concentration within 24 h (peak:trough) were 11.7 +/- 8.14% with conventional formulation as compared to 0% and 1.2 +/- 3.98% with formulation A and B respectively. The mean Tmax for both the controlled release formulations was not statistically significant. On the basis of 90% confidence interval, mean AUC and Cmax values obtained after controlled release formulation A, though statistically significant (P < 0.05) lie well within the prescribed limits of 80-120% as compared to formulation B. Thus both the controlled release formulations were bioequivalent. In comparison to conventional formulation, both controlled release formulations gave lower Cmax, lower AUCs, higher Tmax values, less fluctuation in CBZ plasma concentrations, reduction in ratio of Cmax/AUC values, thus demonstrating controlled release characteristics of the formulation. CONCLUSIONS: Based on the above mentioned parameters both controlled release formulations are bioequivalent and demonstrate controlled release characteristics.

An open clinical trial of benazepril--a new ACE inhibitor in mild-moderate hypertension.

Benazepril hydrochloride, a new non-sulfhydryl ACE inhibitor (ACEI) was studied in a titrated dose of 10 mg-20 mg once a day for 6 weeks in 42 mild to moderate adult hypertensive patients with sitting diastolic blood pressure (SDBP) 95-114 mm Hg. The pre-drug SDBP(mean +/- SE) of 102.5 +/- 0.8 mm Hg showed a significant reduction to 87.5 +/- 0.93 mm Hg at the end of treatment. BP was controlled (SDBP < or = 90 mm Hg) in 34 (81%) patients and a drop of at least 10 mm Hg from the pre-treatment SDBP value was noted in 34 (81%) patients. Common adverse reaction was cough in 8(19%) patients. Clinically significant changes in laboratory evaluations were not seen in any patient. Study showed that benazepril in a dose range of 10 to 20 mg per day is an effective agent for treatment of mild to moderate hypertension.

Retrospective analysis of clinicopathological factors and outcome in breast cancer in young women in a tertiary care hospital in India.

BACKGROUND: The proportion of breast cancer is rising in India. It presents at a younger age in India as compared to the western countries. AIMS: This is a retrospective study of 86 breast cancer patients less than 40 years treated in a single center from June 2006 to June 2011. The aim was to assess the factors that may influence clinical outcome. MATERIALS AND METHODS: Data were collected from medical records. Variables such as age, stage, surgery, chemotherapy, tumor size, grade, nodal status, perinodal extension, lymphovascular emboli, estrogen receptor, progesterone receptor, and HER-2 neu were analyzed in relation to outcome. RESULTS: Out of total 613 breast cancer patients, 91 (14.8%) were younger than 40 years. Five were excluded due to incomplete data; hence, 86 patients were included in this study. Median tumor size was 3 cm and lymph node positivity was 56.9%. Lymphovascular emboli were positive in 48.8% and perinodal extension was positive in 41.8%. Estrogen receptor positivity was 34.8%, progesterone receptor positivity was 45.3%, and triple negativity was 45.3%. The median follow-up period was 27 months with disease free survival being 73.2% and overall survival being 87.2%. In univariate analysis, the factors significantly associated with survival were stage at presentation, presence of lymphovascular emboli, perinodal extension and grade of the tumor. In multivariate analysis grade of tumor was the only significant factor. CONCLUSIONS: In young women with breast cancer, the factors significantly associated with survival were clinical stage at presentation, the presence of lymphovascular emboli and perinodal extension and grade of tumor.

The control of flight force by a flapping wing: lift and drag production.

We used a dynamically scaled mechanical model of the fruit fly Drosophila melanogaster to study how changes in wing kinematics influence the production of unsteady aerodynamic forces in insect flight. We examined 191 separate sets of kinematic patterns that differed with respect to stroke amplitude, angle of attack, flip timing, flip duration and the shape and magnitude of stroke deviation. Instantaneous aerodynamic forces were measured using a two-dimensional force sensor mounted at the base of the wing. The influence of unsteady rotational effects was assessed by comparing the time course of measured forces with that of corresponding translational quasi-steady estimates. For each pattern, we also calculated mean stroke-averaged values of the force coefficients and an estimate of profile power. The results of this analysis may be divided into four main points. (i) For a short, symmetrical wing flip, mean lift was optimized by a stroke amplitude of 180 degrees and an angle of attack of 50 degrees. At all stroke amplitudes, mean drag increased monotonically with increasing angle of attack. Translational quasi-steady predictions better matched the measured values at high stroke amplitude than at low stroke amplitude. This discrepancy was due to the increasing importance of rotational mechanisms in kinematic patterns with low stroke amplitude. (ii) For a 180 degrees stroke amplitude and a 45 degrees angle of attack, lift was maximized by short-duration flips occurring just slightly in advance of stroke reversal. Symmetrical rotations produced similarly high performance. Wing rotation that occurred after stroke reversal, however, produced very low mean lift. (iii) The production of aerodynamic forces was sensitive to changes in the magnitude of the wing's deviation from the mean stroke plane (stroke deviation) as well as to the actual shape of the wing tip trajectory. However, in all examples, stroke deviation lowered aerodynamic performance relative to the no deviation case. This attenuation was due, in part, to a trade-off between lift and a radially directed component of total aerodynamic force. Thus, while we found no evidence that stroke deviation can augment lift, it nevertheless may be used to modulate forces on the two wings. Thus, insects might use such changes in wing kinematics during steering maneuvers to generate appropriate force moments. (iv) While quasi-steady estimates failed to capture the time course of measured lift for nearly all kinematic patterns, they did predict with reasonable accuracy stroke-averaged values for the mean lift coefficient. However, quasi-steady estimates grossly underestimated the magnitude of the mean drag coefficient under all conditions. This discrepancy was due to the contribution of rotational effects that steady-state estimates do not capture. This result suggests that many prior estimates of mechanical power based on wing kinematics may have been grossly underestimated.