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An isolated multilevel bidirectional dc–dc converter is presented in this article to interface the low-voltage (LV) battery and the high-voltage (HV) propulsion inverter in electric vehicles. The proposed topology achieves a HV step-up ratio in the motoring mode by reconfiguring two split capacitor half-bridge circuits in series/parallel through the symmetrical modulation of a voltage bidirectional, two quadrant switch. This reconfiguration generates a high-frequency multilevel voltage output at the dc-bus side of the inverter, which reduces the output filter volume. The dc-bus voltage is regulated by the duty cycle modulation of the intermediary switch in the motoring mode, simplifying the sensing and control. During regenerative braking, the converter is operated with phase shift modulation between the HV half bridges and the LV full bridge to regulate the battery voltage. The presented modulation strategies achieve zero voltage switching for the full-bridge devices over a wide load range. A comprehensive analysis of the proposed multilevel converter in motoring and braking modes along with the design constraints and soft switching boundary conditions is presented in this article. Detailed experimental results on a 1.5-kW laboratory prototype are presented to verify the design approach and illustrate the converter performance. [ABSTRACT FROM AUTHOR]

Background: Chronic kidney disease (CKD) not associated with known risk factors, called CKD of unknown etiology (CKDu), has been reported from several geographically distinct regions across the world. This study reports the clinical and epidemiological profile of patients with CKDu from a new hotspot in central India. Materials and Methods: This cross-sectional study describes the sociodemographic, clinical, and laboratory profile of the patients diagnosed with CKDu visiting a tertiary care public hospital in the state of Chhattisgarh in central India between June 2019 and June 2021. CKDu was diagnosed as progressive CKD, minimal proteinuria, absence of hematuria, diabetes, severe hypertension, systemic illness, glomerulonephritis or other urinary tract diseases, and presence of symmetrically contracted kidneyon ultrasound. Results: A total of 166 (3.1%) out of 5365 patients with CKD were diagnosed with CKDu. The mean age was 53.6 ± 11.8 years. The patients were predominantly male (n = 113, 68.1%), belonged to rural areas (n = 147, 88.6%), and were engaged in farming (n = 105, 63.3%). The estimated glomerular filtration rate (eGFR) at presentation was 21.5 ± 15.1 ml/min/1.73m². Forty-four (26.5%) had stage 3 CKD, 57 (34.3%) had stage 4 CKD, and 65 (39.2%) had stage5 CKD. There was an over-representation of CKDu cases in patients with CKD from Gariyaband (36.0%) and Mahasamund (25%) districts of Chhattisgarh and Nuapada (35.0%) and Balangir (30.0%) districts of Odisha. Conclusion: The study suggests clustering of cases of CKDu in certain districts of Orissa and Chhattisgarh. [ABSTRACT FROM AUTHOR]

Parasitic infections do not usually present with rapidly progressive renal failure but can provoke glomerular lesions which are mostly proliferative. In filarial infection, glomerular involvement is usually mild and transient, and presentation with renal failure is rare. We report occult filariasis presenting as rapidly progressive renal failure due to immune-complex mediated membranoproliferative glomerulonephritis. Our patient responded to treatment with diethylcarbamazine and a short course of steroid. This case highlights the importance of thorough workup to identify the cause and consideration of filariasis in an endemic area. [ABSTRACT FROM AUTHOR]

This article proposes a multilevel dc–dc converter topology for fast charging of electric and plug-in hybrid electric vehicles (EVs and PHEVs). The proposed dc–dc converter topology converts the front end ac–dc converter output and provides regulated supply to the EV propulsion battery. The proposed topology consists of full-bridge converter at the primary, while the secondary side consists of voltage doubler rectifier units and combination of diodes and mosfet for reconfiguration of the voltage doubler rectifiers to generate the multilevel voltage. The multilevel voltage at the output helps in reducing the output filter size and increases the power density of the converter. The topology utilizes the resonance between leakage inductor of high frequency transformer, parasitic output capacitors of full-bridge mosfets and voltage doubler capacitors to achieve soft switching (ZVS turn-on) for all the full-bridge devices and soft turn-offfor the rectifier diodes. The load limited ZVS turn on capability of conventional full-bridge topologies is mitigated through the use of resonance between magnetizing inductance of transformer and mosfet output capacitors. The converter is designed for 650 V dc bus input and 200–400 V EV battery output at 100 kW rated charging power. The analysis of the proposed converter in continuous and discontinuous modes of operation, soft switching operation, and the component design guidelines are presented in this article. The proposed converter is validated through detailed PLECS simulation results for 100 kW charging power. Experimental results from laboratory prototype of 500 W power are also presented to validate the design methodology and converter performance. [ABSTRACT FROM AUTHOR]

Background: A phase 3 study to assess the efficacy and safety of the desidustat, an oral hypoxia-inducible factor prolyl hydroxylase inhibitor, against the epoetin alfa for the treatment of anemia in patients with chronic kidney disease (CKD) with dialysis dependency. Methods: DREAM-D was a phase 3, multicenter, open-label, randomized, active-controlled clinical study conducted across 38 centers in India. A total of 392 patients with clinical diagnosis of anemia due to CKD with dialysis need (Erythrocyte Stimulating Agent [ESA] naïve or prior ESA users) and with baseline hemoglobin levels of 8.0–11.0 g/dL (inclusive) were randomized in a 1:1 ratio to receive either desidustat oral tablets (thrice a week) or epoetin alfa subcutaneous injection for 24 weeks to maintain a hemoglobin level of 10–12 g/dL. The primary endpoint was to assess the change in the hemoglobin level between the desidustat and the epoetin alfa groups from the baseline to evaluation period week 16–24. The key secondary efficacy endpoint was the number of patients with hemoglobin response. Results: The least square mean (standard error) change in hemoglobin from the baseline to week 16–24 was 0.95 (0.09) g/dL in the desidustat group and 0.80 (0.09) g/dL in the epoetin alfa group (difference: 0.14 [0.14] g/dL; 95% confidence interval: −0.1304, 0.4202), which met the prespecified noninferiority margin. The number of hemoglobin responders was significantly higher in the desidustat group (106 [59.22%]) when compared to the epoetin alfa group (89 [48.37%]) (p = 0.0382). The safety profile of the desidustat oral tablet was comparable with the epoetin alfa injection. There were no new risks or no increased risks seen with the use of desidustat compared to epoetin alfa. Conclusion: In this study, desidustat was found to be noninferior to epoetin in the treatment of anemia in CKD patients on dialysis and it was well-tolerated. Clinical Trial Registry Identifier: CTRI/2019/12/022312 (India). [ABSTRACT FROM AUTHOR]

The CLARITY trial (Controlled evaLuation of Angiotensin Receptor Blockers for COVID-19 respIraTorY disease) is a two-arm, multi-centre, randomised controlled trial being run in India and Australia that investigates the effectiveness of angiotensin receptor blockers in addition to standard care compared to placebo (in Indian sites) with standard care in reducing the duration and severity of lung failure in patients with COVID-19. The trial was designed as a Bayesian adaptive sample size trial with regular planned analyses where pre-specified decision rules will be assessed to determine whether the trial should be stopped due to sufficient evidence of treatment effectiveness or futility. Here, we describe the statistical analysis plan for the trial and define the pre-specified decision rules, including those that could lead to the trial being halted. The primary outcome is clinical status on a 7-point ordinal scale adapted from the WHO Clinical Progression scale assessed at day 14. The primary analysis will follow the intention-to-treat principle. A Bayesian adaptive trial design was selected because there is considerable uncertainty about the extent of potential benefit of this treatment.Trial registrationClinicalTrials.gov NCT04394117 . Registered on 19 May 2020Clinical Trial Registry of India CTRI/2020/07/026831Version and revisionsVersion 1.0. No revisions. [ABSTRACT FROM AUTHOR]

Horseshoe kidney is a common congenital renal fusion anomaly. Acute kidney injury occurs secondary to urinary infection or obstructive uropathy, but glomerular involvement is rarely reported. A 47-year-old female presented with symptoms of urinary infection and was hospitalized in the urology clinic. Investigations revealed renal dysfunction and active urine sediments. The patient did not respond to antibiotics and eventually became anuric after 3 weeks of initiation of symptoms. Abdominal ultrasound was suggestive of horseshoe kidney. Workup for rapidly progressive glomerulonephritis and kidney biopsy confirmed the diagnosis of anti-glomerular basement membrane disease. The patient responded to immunosuppression and plasmapheresis. The above case highlights the importance of timely renal biopsy in diagnosis and management of glomerular disease even in patients with horseshoe kidney. [ABSTRACT FROM AUTHOR]

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are novel antidiabetic agents with overwhelming cardiorenal protection. Recent trials focusing on the nephroprotective role of SGLT2i have underscored its success as a phenomenal agent in halting the progression of kidney disease in patients with and without Type 2 diabetes mellitus. Multitudes of pleiotropic effects on tubules have raised hopes for reasonable nephroprotection beyond the purview of the hyperglycemic milieu. This review summarizes various animal and human data as evidence for the utility of SGLT2i in non-diabetic chronic kidney disease (CKD). Web-based medical database entries were searched. On the premise of existing evidence, we have discussed mechanisms likely contributing to nephroprotection by SGLT2i in patients with non-diabetic CKD. Further elucidation of mechanisms of nephroprotection offered by SGLT2i is required to extend its use as a nephroprotective agent. The use of non-traditional markers of kidney damage in future studies would improve the evaluation of their role in attenuating CKD progression. Emerging animal data support the early use of SGLT2i in states of modest proteinuria for superior outcomes. Future long-term trials in patients should aim to address the time of intervention with SGLT2i during the natural disease course of CKD for best outcomes. [ABSTRACT FROM AUTHOR]

Various factors interplay when it comes to successful containment of pandemic. In last one year, we have witnessed various countries formulating and practicing their own unique ways to tackle coronavirus. We have seen the most developed countries failing terribly and unable to slow the COVID-19 spread, but at the same time also endorsed the comparatively less resourceful countries outperforming in terms of reduced disease morbidity and mortality. Current review is about two regions from India (Dharavi and Kerala) who were different in their approach as compared to rest of the country and were able to keep the COVID-19 cases to the minimum. [ABSTRACT FROM AUTHOR]

The severe respiratory disease COVID-19 (coronavirus disease 2019) was first reported in late December 2019 in Wuhan City, China. Soon thereafter, the World Health Organization (WHO) officially declared it a pandemic. The adult population is highly affected by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2); however, infants and children are also not spared. Transmission in the pediatric population appears to be primarily from COVID-19-positive adults, largely from family contacts through droplets, direct contacts, and aerosols. There is also evidence of fecal-oral route of transmission. The incubation period of COVID-19 in children ranges from 2 to 10 days. Most children are asymptomatic. The most common symptoms amongst symptomatic children are fever and cough. Shortness of breath, sore throat, rhinorrhea, conjunctivitis, fatigue, and headache are other common symptoms. Diarrhea, vomiting, and abdominal pain are the common gastrointestinal symptoms that may be present with or without respiratory symptoms. Very few children are likely to develop severe disease. Supportive care is the mainstay of treatment. Though data are limited, antiviral therapies such as remdesivir, favipiravir, lopinavir/ritonavir, and other drugs like hydroxychloroquine/chloroquine have been used for severe COVID-19 cases, with remdesivir showing the greatest promise. A few children may develop an exaggerated immune response, characterized by exaggerated cytokine release and manifests with features similar to Kawasaki disease. The syndrome has been referred to by many names including pediatric inflammatory multisystem syndrome (PIMS) and more recently, as multisystem inflammatory syndrome in children (MIS-C); this life-threatening condition often requires a multidisciplinary team effort and use of immunomodulators. [ABSTRACT FROM AUTHOR]

Chronic Kidney Disease (CKD) is emerging as a major public health priority worldwide. It is a chronic condition influenced by lifestyle and behavior. The risk factors for CKD are highly prevalent among the Indian population, and the number of Indians at risk is increasing. Preventive measures focusing on reducing the prevalence of CKD by limiting exposure to risk factors could be cost effective in a country like India. Kidney diseases disproportionally affect disadvantaged populations and reduce the number of productive years of life. Furthermore, the prospect of financial burden discourages many patients from undergoing treatment, thereby leading to preventable morbidity and death. The management of patients with CKD is focused on early detection or prevention, treatment of the underlying cause (if possible) to curb progression and attention to secondary processes that contribute to ongoing nephron loss. Blood pressure control, inhibition of the renin-angiotensin system and disease-specific interventions are the cornerstones of therapy. Health literacy and self-management are critical to improving the outcomes of chronic conditions such as chronic kidney disease. Primary Care and Family physicians act as a bridge between the nephrologist specialist and the CKD patients; which will help in improving the quality of life, reduce physical and psychologic limitations and complications associated with CRF, and help patients return to their families, jobs, and social lives [ABSTRACT FROM AUTHOR]

Chylothorax is an uncommon presentation of venous thrombosis in nephrotic syndrome. We present a case of an 8-year-old boy with nephrotic syndrome who presented with prolonged respiratory difficulty and dry cough. A detailed evaluation revealed left chylothorax secondary to thrombosis of the left brachiocephalic vein. He improved with conservative management including anticoagulation therapy, intercostal chest tube drainage, and dietary modification. This case highlights the need to consider venous thrombosis as a cause of chylothorax in patients with nephrotic syndrome to institute appropriate treatment. [ABSTRACT FROM AUTHOR]

Abstracts of oral and poster presentations from the annual conference of Indian Society of Nephrology held in Mumbai, India on December 15-18, 2016 are presented, including follow-up study on metformin safety in diabetics with chronic kidney disease (CKD), incidence of acute kidney injury in patients admitted to the intensive care unit in tertiary care hospital, and the clinical profile of patients with autosomal dominant polycystic kidney disease (ADPKD).

Background:: Data on outcome of children undergoing in-hospital cardiopulmonary resuscitation (CPR) in low- and middle-income countries are scarce. Aims:: To describe the clinical profile and outcome of children undergoing in-hospital CPR. Methods:: This prospective observational study was undertaken in the Advanced Pediatric Center, PGIMER, Chandigarh. All patients aged 1 month to 12 years who underwent in-hospital CPR between July 2010 and March 2011 were included. Data were recorded using the ‘Utstein style’. Outcome variables included ‘sustained return of spontaneous circulation’ (ROSC), survival at discharge and neurological outcome at 1 year. Results:: The incidence of in-hospital CPR in all hospital admissions (n = 4654) was 6.7% (n = 314). 64.6% (n = 203) achieved ROSC, 14% (n = 44) survived to hospital discharge and 11.1% (n = 35) survived at 1 year. Three-quarters of survivors had a good neurological outcome at 1-year follow-up. Sixty per cent of patients were malnourished. The Median Pediatric Risk of Mortality-III (PRISM-III) score was 16 (IQR 9–25). Sepsis (71%), respiratory (39.5%) and neurological (31.5%) illness were the most common diagnoses. The most common initial arrhythmia was bradycardia (52.2%). On multivariate logistic regression, duration of CPR, diagnosis of sepsis and requirement for vasoactive support prior to arrest were independent predictors of decreased hospital survival. Conclusions:: The requirement for in-hospital CPR is common in PGIMER. ROSC was achieved in two-thirds of children, but mortality was higher than in high-income countries because of delayed presentation, malnutrition and severity of illness. CPR >15 min was associated with death. Survivors had good long-term neurological outcome, demonstrating the value of timely CPR. [ABSTRACT FROM AUTHOR]

In the second of two features on the history and future of the fibre market, the author asks whether we are or the brink of a new fibre-optic network revolution. [ABSTRACT FROM AUTHOR]

From the explosion in YouTube traffic to the 'iPhone effect' on mobile broadband, or the rapid expansion of software as a service in the enterprise, service providers are faced with a new era of bandwidth demand driven by a new set of users. According to a 2006 report from Enterprise Strategy Group, anticipated bandwidth demands globally for services such as internet protocol (IP) video, multimedia messaging, internet access and corporate data connectivity are expected to exceed 23,000 petabytes per month by 2010, with a roughly 35 per cent compound annual growth rate from 2006 to 2010. In addition to growing bandwidth demand, carriers are faced with declining revenues per bit, increasing network churn and more traffic mix uncertainty than ever before. Consequently, these trends are forcing operators to change their approach to building networks and delivering services. To maintain growth, service providers need networks that enable rapid revenue expansion and service creation velocity while simultaneously lowering expenditures. To address these business challenges, transport networks must transition from circuit- to packet-optimised architectures and become more service-driven by introducing capabilities such as on-demand network programmability, intelligence and automation, and take advantage of technologies such as packet-optical, carrier Ethernet and even 100G in the long term. Service providers must radically transform their networks from a commodity to a differentiated asset while optical and carrier Ethernet networking equipment vendors must stay at the cutting edge of technology innovation to give their customers a competitive advantage. [ABSTRACT FROM AUTHOR]

Chylous ascites is a rare complication of peritoneal dialysis (PD) and is often mistaken for peritonitis. It usually resolves following conservative management and does not pose any risk to the dialysis procedure. We report the case of a 2-year-old boy, who developed chylous ascites at 36 hours of PD and spontaneously resolved within the next 48 hours. [ABSTRACT FROM AUTHOR]

The article discusses various reports published within the issue, including one on the regulatory change for telecommunication system, one on the importance of fxed-mobile convergence approaches and on telecommunication companies business strategy to attract more customers.