Publications by authors named "Mahesh Nanjundappa"

The global crisis of antimicrobial resistance (AMR) necessitates the development of broad-spectrum antibacterial drugs effective against multi-drug resistant (MDR) pathogens. BWC0977, a Novel Bacterial Topoisomerase Inhibitor (NBTI) selectively inhibits bacterial DNA replication via inhibition of DNA gyrase and topoisomerase IV. BWC0977 exhibited a minimum inhibitory concentration (MIC) of 0.

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Persistent pulmonary hypertension of the newborn (PPHN) can be monitored theoretically by the difference of the partial pressure of arterial (PaCO) to end-tidal CO (EtCO). We aimed to test the hypothesis that the PaCO-EtCO gradient in infants with PPHN would be higher compared to infants without PPHN. Prospective, observational study of term-born ventilated infants with echocardiographically-confirmed PPHN with right-to-left shunting and term-born control infants without respiratory disease.

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The neutropenic mouse infection model is extensively used to characterize the pharmacokinetics/pharmacodynamics (PK/PD) of anti-infective agents. However, it is difficult to evaluate agents following intravenous (i.v.

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Background: The main pathophysiologic characteristic of chronic respiratory disease following extremely premature birth is arrested alveolar growth, which translates to a smaller alveolar surface area (S). We aimed to use non-invasive measurements to estimate the S in extremely preterm infants.

Methods: Paired measurements of the fraction of inspired oxygen and transcutaneous oxygen saturation were used to calculate the ventilation/perfusion ratio, which was translated to S using Fick's law of diffusion.

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Background: Patent ductus arteriosus (PDA) and diaphragmatic dysfunction are frequently seen in newborn infants but their relationship remains unknown. We aimed to use point of care ultrasound to compare diaphragmatic kinetics in infants with a PDA compared to in those without a PDA.

Methods: M-mode ultrasonography was used to measure the mean inspiratory velocity ( ) in newborn infants with and without a haemodynamically significant PDA admitted in the Neonatal Unit at King's College Hospital during a three month period.

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Unlabelled: The use of inhaled nitric oxide (iNO) in treating pulmonary hypertension in infants with congenital diaphragmatic hernia (CDH) is controversial. Our aims were to identify factors associated with survival in CDH infants and whether this was influenced by the response to iNO. Results of CDH infants treated in a tertiary surgical and medical perinatal centre in a ten year period (2011-2021) were reviewed.

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Objectives: Pulmonary hypertension (PH) is a complication of bronchopulmonary dysplasia (BPD) and associated with increased mortality and morbidity. Our aim was to identify, in infants with BPD, the effect of PH on health-care utilisation and health related cost of care.

Methods: An electronic data recording system was used to identify infants ≤32 weeks of gestation who developed BPD.

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Background: The translation of Pharmacokinetics (PK)/Pharmacodynamics (PD) from preclinical models to the clinic has not been studied in detail for drugs used to treat complicated urinary tract infections (cUTI).

Objective: The PK/PD of Ciprofloxacin (CIP), a drug used to treat cUTI, was evaluated in a mouse model of cUTI infected with Escherichia coli, and compared with clinical PK/PD in cUTI patients.

Methods: Streptozotocin induced diabetic female BALB/c mice were infected transurethrally with Escherichia coli.

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PA-824 is a bicyclic 4-nitroimidazole, currently in phase II clinical trials for the treatment of tuberculosis. Dose fractionation pharmacokinetic-pharmacodynamic studies in mice indicated that the driver of PA-824 in vivo efficacy is the time during which the free drug concentrations in plasma are above the MIC (fT>MIC). In this study, a panel of closely related potent bicyclic 4-nitroimidazoles was profiled in both in vivo PK and efficacy studies.

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Tetrahydropyrazolo[1,5-a]pyrimidine scaffold was identified as a hit series from a Mycobacterium tuberculosis (Mtb) whole cell high through-put screening (HTS) campaign. A series of derivatives of this class were synthesized to evaluate their structure-activity relationship (SAR) and structure-property relationship (SPR). Compound 9 had a promising in vivo DMPK profile in mouse and exhibited potent in vivo activity in a mouse efficacy model, achieving a reduction of 3.

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New chemotherapeutic compounds against multidrug-resistant Mycobacterium tuberculosis (Mtb) are urgently needed to combat drug resistance in tuberculosis (TB). We have identified and characterized the indolcarboxamides as a new class of antitubercular bactericidal agent. Genetic and lipid profiling studies identified the likely molecular target of indolcarboxamides as MmpL3, a transporter of trehalose monomycolate that is essential for mycobacterial cell wall biosynthesis.

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New therapeutic strategies are needed to combat the tuberculosis pandemic and the spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) forms of the disease, which remain a serious public health challenge worldwide. The most urgent clinical need is to discover potent agents capable of reducing the duration of MDR and XDR tuberculosis therapy with a success rate comparable to that of current therapies for drug-susceptible tuberculosis. The last decade has seen the discovery of new agent classes for the management of tuberculosis, several of which are currently in clinical trials.

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Candidate antibacterials are usually identified on the basis of their in vitro activity. However, the apparent inhibitory activity of new leads can be misleading because most culture media do not reproduce an environment relevant to infection in vivo. In this study, while screening for novel anti-tuberculars, we uncovered how carbon metabolism can affect antimicrobial activity.

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Bacterial peptide deformylase (PDF) belongs to a subfamily of metalloproteases catalyzing the removal of the N-terminal formyl group from newly synthesized proteins. We report the synthesis and biological activity of highly potent inhibitors of Mycobacterium tuberculosis (Mtb) PDF enzyme as well as the first X-ray crystal structure of Mtb PDF. Structure-activity relationship and crystallographic data clarified the structural requirements for high enzyme potency and cell based potency.

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Peptide deformylase (PDF) catalyzes the hydrolytic removal of the N-terminal formyl group from nascent proteins. This is an essential step in bacterial protein synthesis, making PDF an attractive target for antibacterial drug development. Essentiality of the def gene, encoding PDF from Mycobacterium tuberculosis, was demonstrated through genetic knockout experiments with Mycobacterium bovis BCG.

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