COVID-19 restrictions and their influences on ambient air, surface water and plastic waste in a coastal megacity, Chennai, India

Anthropogenic activities experienced a pause due to the nationwide lockdown, imposed to contain the rapid spread of COVID-19 in the third week of March 2020. The impacts of suspension of industrial activities, vehicular transport and other businesses for three months (25 March-30 June) on the environmental settings of Chennai, a coastal megacity was assessed. A significant reduction in the key urban air pollutants [PM_2.5 (66.5%), PM₁₀ (39.5%), NO₂ (94.1%), CO (29%), O₃ (45.3%)] was recorded as an immediate consequence of the reduced anthropogenic activities. Comparison of water quality of an urban river Adyar, between pre-lockdown and lockdown, showed a substantial drop in the dissolved inorganic N (47%) and suspended particulate matter (41%) during the latter period. During the pandemic, biomedical wastes in India showed an overall surge of 17%, which were predominantly plastic. FTIR-ATR analysis confirmed the polymers such as polypropylene (25.4%) and polyester (15.4%) in the personal protective equipment.

Seagrass litter decomposition: an additional nutrient source to shallow coastal waters

Seagrass ecosystems are vital for its regulatory services yet, highly threatened by degradation due to human pressures. Decomposition of two tropical seagrass species (Cymodocea serrulata and Cymodocea rotundata) was studied and compared, to understand their potential in generating additional nutrients to coastal waters. Release of carbon, nitrogen and phosphorus during the decomposition process of seagrass wracks was estimated in bacteria-active (non-poisoned) and bacteria-inhibited (poisoned) conditions from shore-washed fresh seagrass, sampled from Palk Bay, India. Incubation experiments for 25 days indicated a near three times higher concentration of dissolved organic carbon (DOC) in bacteria-inhibited flasks compared to bacteria-active conditions for both species. The maximum leaching rates of DOC, TDN and TDP were found to be 294, 65.1 and 11.2 μM/g dry wt/day, respectively. Further, higher release of dissolved inorganic nitrogen (DIN) (> 1.3 times) was documented from the bacteria-active flask, highlighting the significance of microbial process in generating bio-available nutrients from decaying seagrass. Faster decomposition (0.014 ± 0.004 day^-1) in the initial stages (up to 8 days) compared to the later stages (0.005 ± 0.001 day^-1) indicated a rapid loss of biomass carbon during the initial leaching process and its relative importance in the decomposition pathway. The decomposition rate is best described by a single-stage exponential decay model with a half-life of 41 days. It is estimated that the total seagrass litter available along the Palk Bay coast is about ~ 0.3 Gg with high potential of additional nitrogen (0.9 ± 0.5 Mg) and phosphorus (0.3 ± 0.1 Mg) supply to the adjacent coastal waters.

Seagrass and macrophyte mediated CO2 and CH4 dynamics in shallow coastal waters

Seagrass meadows are among the most important coastal/ marine ecosystems for long-term carbon storage and conditioning of coastal waters. A combined air-water flux of CO2 and CH4 from the seagrass meadows was studied for the first time from Asia's largest brackish-water lagoon, Chilika, India. Ecosystem-based comparisons were carried out during two hydrologically different conditions of dry and wet seasons in the seagrass dominated southern sector (SS); macrophyte-dominated northern sector (NS); the largely un-vegetated central sector (CS) and the tidally active outer channel (OC) of the lagoon. The mean fluxes of CO2 from SS, NS, CS and OC were 9.8, 146.6, 48.4 and 33.0mM m-2d-1, and that of CH4 were 0.12, 0.11, 0.05 and 0.07mM m-2d-1, respectively. The net emissions (in terms of CO2 equivalents), considering the global warming potential of CO2 (GWP: 1) and CH4 (GWP: 28) from seagrass meadows were over 14 times lower compared to the macrophyte-dominated sector of the lagoon. Contrasting emissivity characteristics of CO2 and CH4 were observed between macrophytes and seagrass, with the former being a persistent source of CO2. It is inferred that although seagrass meadows act as a weak source of CH4, they could be effective sinks of CO2 if land-based pollution sources are minimized.

A Multicenter, Prospective, Randomized, Double-blind Study to Evaluate the Safety and Efficacy of Saroglitazar 2 and 4 mg Compared to Pioglitazone 45 mg in Diabetic Dyslipidemia (PRESS V)

Dual PPARα/γ can improve both metabolic effects and minimized the side effects caused by either PPARα or PPARγ agonist. The PRESS V study was aimed to evaluate the safety, tolerability, and efficacy of saroglitazar 2 mg and 4 mg capsules (Lipaglyn™; Zydus Code: ZYH1) as compared to high dose pioglitazone in patients with diabetic dyslipidemia. In this 26-week double-blind, parallel arm, phase 3 study patients with hypertriglyceridemia with type 2 diabetes mellitus (BMI > 23 kg/m²; hypertriglyceridemia: TG > 200 to 400 mg/dL; glycosylated hemoglobin [HbA_1c] >7 to 9%) were enrolled from 14 sites in India. After 2 weeks of lifestyle modification, 122 patients were randomized double-blind to 24-week treatment with the study drugs (saroglitazar 2 mg or 4 mg or pioglitazone 45 mg once daily) in a 1:1:1 ratio. The primary end point was change in plasma triglyceride level at week 24. The secondary end points were change in lipid profile and fasting plasma glucose at week 24. Patients who received study medication and had undergone at least 1 postbaseline efficacy evaluation were included in the efficacy analysis. All randomized patients who received at least a single dose were included for safety evaluation. The efficacy analysis included 109 patients (n = 37 in saroglitazar 2 mg; n = 39 in saroglitazar 4 mg; n = 33 in pioglitazone). Saroglitazar 2 mg and 4 mg significantly reduced (P < .001) plasma triglyceride from baseline by 26.4% (absolute change ± SD: -78.2 ± 81.98 mg/dL) and 45% (absolute change ± SD -115.4 ± 68.11 mg/dL), respectively, as compared to pioglitazone -15.5% (absolute change ± SD: -33.3 ± 162.41 mg/dL) at week 24. Saroglitazar 4 mg treatment also demonstrated marked decrease in low-density lipoprotein (5%), very-low-density lipoprotein (45.5%), total cholesterol (7.7%), and apolipoprotein-B (10.9%). Saroglitazar treatment was generally safe and well tolerated. No serious adverse events were reported in saroglitazar treatment arm and no persistent change in laboratory parameters. Saroglitazar appeared to be an effective and safe therapeutic option for improving hypertriglyceridemia in patients with type 2 diabetes mellitus.

Clinical experience with insulin detemir, biphasic insulin aspart and insulin aspart in people with type 2 diabetes: Results from the Chennai cohort of the A1chieve study

BACKGROUND

The A1chieve, a multicentric (28 countries), 24-week, non-interventional study evaluated the safety and effectiveness of insulin detemir, biphasic insulin aspart and insulin aspart in people with T2DM (n = 66,726) in routine clinical care across four continents.

MATERIALS AND METHODS

Data was collected at baseline, at 12 weeks and at 24 weeks. This short communication presents the results for patients enrolled from Chennai, India.

RESULTS

A total of 1334 patients were enrolled in the study. Four different insulin analogue regimens were used in the study. Patients had started on or were switched to biphasic insulin aspart (n = 983), insulin detemir (n = 205), insulin aspart (n = 42), basal insulin plus insulin aspart (n = 41) and other insulin combinations (n = 63). At baseline glycaemic control was poor for both insulin naïve (mean HbA1c: 9.4%) and insulin users (mean HbA1c: 9.3%) groups. After 24 weeks of treatment, both groups showed improvement in HbA1c (insulin naïve: -2.1%, insulin users: -1.9%). SADRs including major hypoglycaemic events or episodes did not occur in any of the study patients.

CONCLUSION

Starting or switching to insulin analogues was associated with improvement in glycaemic control with a low rate of hypoglycaemia.

Prevalence of gestational diabetes mellitus in South India (Tamil Nadu)--a community based study

AIM

Women diagnosed to have Gestational Diabetes Mellitus (GDM) are at increased risk of developing diabetes in future. Thus, diagnosis of GDM is an important public health issue. In a random survey 16.2% of pregnant women were found to have GDM in the Chennai urban population. Hence we undertook a planned community based study to ascertain the prevalence of GDM.

MATERIALS AND METHODS

We conducted a prospective screening for GDM in the urban, semi urban and rural areas. All pregnant women irrespective of gestational weeks underwent a 75 g glucose challenge test in the fasting state. Diagnosis of GDM was made if the 2 hr plasma glucose was > or = 140 mg/dl (WHO criteria).

RESULTS

A total of 4151, 3960 and 3945 pregnant women were screened in urban, semi urban and rural areas, respectively. GDM was detected in 739 (17.8%) women in urban, 548 (13.8%) in semi urban and 392 (9.9%) in rural areas. Out of 1679 GDM women, 1204 (72%) were detected in first visit and the remaining 28% in subsequent visits. A significant increase (P < 0.0001) in the prevalence of GDM was observed with family history of diabetes, increased maternal age and BMI. A trend for increased prevalence of GDM was observed in women with less physical activity, however, not statistically significant.

CONCLUSION

In this community based study, the prevalence of GDM varied in the urban, semi urban and rural areas. Age > or = 25 years, BMI > or = 25 and family history of diabetes were found to be risk factors for GDM.

Gestational diabetes mellitus manifests in all trimesters of pregnancy

Screening for GDM is usually performed around 24-28 weeks of gestational age. We undertook a study to estimate the prevalence of glucose intolerance during different trimesters, as data in this aspect is sparse. A total of 4151 consecutive pregnant women irrespective of gestational weeks attending antenatal health posts across Chennai city underwent a 75 g OGTT recommended by WHO and diagnosed GDM if 2 hr PG value > or =140 mg/dl. Women who had normal OGTT at the first visit were screened with a repeat OGTT at the subsequent visits. Among the screened, 741 women (17.9%) had 2 hr PG> or =140 mg/dl and were identified to have gestational diabetes. Analysis based on gestational weeks revealed that out of the 741 GDM women, 121 (16.3%) were within 16 weeks, 166 (22.4%) were between 17 and 23 weeks and 454 (61.3%) were more than 24 weeks of gestation. Observation in this study was that 38.7% developed gestational diabetes even prior to 24th week of gestation. Out of the total 741 GDM women, 214 (28.9%) were diagnosed on repeat testing at subsequent visits. Glucose intolerance occurs in the early weeks of gestation. Women who had normal glucose tolerance in the first visit require repeat OGTT in the subsequent visits.