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The article presents a hospital-based study which examined whether social backwardness is a determinant of preterm birth and adverse neonatal outcomes. The research was conducted in a tertiary care hospital in eastern India and focused on the occurrence of prematurity among social categories like other background classes (OBC), scheduled castes (SC) and scheduled tribes (ST).

In this paper, ultra-low level selective detection of bovine serum albumin (BSA) has been demonstrated, based on chemically derived graphene i.e., reduced graphene oxide (RGO) nanosheets. The working principle of the sensor is based upon change in conductance of the RGO nanosheets with different concentration of BSA. The change in conductance is based on the charge transfer between BSA and functional groups of RGO. The morphological and structural characterizations of RGO nanosheets were carried out by scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Raman spectroscopy is performed to further validate the interaction between RGO sensing layer and BSA molecules. Electrical impedance spectroscopy is performed to observe the impedance variation when BSA interacts with RGO. The sensor device exhibits sensitivity of 10 nA/pM. The lower limit of detection (LOD) of the sensor is found to be 1 pM and response time around 35 s, confirming very high sensitivity for BSA. All electrical (current-voltage) measurements were carried out at 2 V bias for low power operation. The sensor exhibits highest sensitivity at 30 °C and for RGO thickness ~4 nm. The RGO based sensor device is selective towards BSA when compared to proteins like L-Histidine, HSA, BHB and Biotin. Our results suggest that RGO based devices are promising for low-cost, portable and real time detection of BSA at room temperature. [ABSTRACT FROM AUTHOR]

Background: Thrombocytopenia as a side effect of phototherapy has not been mentioned in standard literature and textbooks. Though there are few studies in this regard, but results are conflicting. Aims and Objective: Hence, the present study is undertaken to find out whether any significant change in platelet count occurs following phototherapy, and if there be any, to see whether the changes are transient or not. Materials and Methods: This prospective and observational study was carried out over a period of one and half years (1st March 2019 to 31st August 2020) on 190 new-borns admitted with idiopathic unconjugated hyperbilirubinemia needing phototherapy through consecutive enrolment. Serum bilirubin (total, conjugated and unconjugated) and platelet count were done before initiation and just after completion of phototherapy, and seven days after completion of phototherapy. Appropriate statistical tests were used to make statistical comparisons with a p-value of < 0.05 taken as significant. Results: Among 190 neonates, 108(56.8%) were male and 82(43.2%) were female; 90(47.4%) were preterm and 100(52.6%) were term. Mean birth weight was (2.4725 ± 0.4782) kg. Mean gestational age was (36.4316 ± 2.4802) weeks. Mean haemoglobin level was (17.3816± 1.0784) gm/dl. Mean age at presentation was (4.5737± 1.5811) days. Mean total serum bilirubin (TSB) before initiation, after completion, and 7 days after completion of phototherapy were (17.8595 ± 3.7034) mg/dl, (8.1726 ± 2.2586) mg/dl and (5.7279± 1.5918) mg/dl respectively. The mean duration of phototherapy required was (48.1895 ± 13.6054) hours. Mean platelet count before initiation and just after completion of phototherapy were (2,49,321.0526± 89,460.2101)/µL and (2,22,436.8421 ± 88,538.7173)/µL respectively. Mean platelet count 7days after completion of phototherapy was (2,46,210.5263 ± 87,442.3038)/µL. Decrease in platelet count just after completion of phototherapy was statistically significant. Fifty-nine (31.1%) out of 190 neonates developed mild thrombocytopenia (100000- <150000/µL) just after completion of phototherapy, but none developed moderate or severe thrombocytopenia. None having thrombocytopenia manifested with clinical bleed. Platelet count raised near to pre-phototherapy level 7 days after completion of phototherapy. Fall in platelet count was found to have a positive association with increased duration of phototherapy and lower gestational age (p<0.0001). However, there was no statistically significant association (p>0.05) between reduction in platelet count with gender. Conclusions: Though the incidence of thrombocytopenia following phototherapy was significant, but it was mostly mild and transient, and clinically insignificant. There was significant association between decrease of platelet count with duration of phototherapy and lower gestational age. [ABSTRACT FROM AUTHOR]

Background: Pulled elbow is a common injury of early childhood that results in subluxation of the annular ligament due to a sudden longitudinal traction applied to the hand. Treatment is usually closed reduction with either a supination-flexion or a hyperpronation technique. Aims and Objectives: Present study is aimed to make pediatricians aware of the fact that most of such cases can be easily diagnosed and successfully reduced in office settings without much fear and complications. Materials and Methods: All cases with typical history and clinical presentation were included in the study and were subjected to supination-flexion maneuver. When the first attempt failed, a second attempt using the same technique was performed. After failure of the second attempt, hyperpronation was tried. Results: Among 49 patients included in the study, 27 (55.10 %) were girls and 22 (44.89 %) were boys. Mean age at presentation was 20.12 months. All of them were below 4 years of age. Forty-five patients were successfully reduced on the first attempt using supination-flexion maneuver, 2 patients required a second attempt using same technique. One patient was reduced with hyperpronation technique 15 minutes after first 2 attempts failed. Only 1 patient required referral to an orthopedic expert as all 3 attempts were in vain, but the child eventually recovered. Conclusion: All pediatricians should learn to diagnose and treat the condition to reduce delay in treatment and avoid complications. [ABSTRACT FROM AUTHOR]

This study investigated the role of an allochthonous Gram-positive wastewater bacterium (Bacillus sp. KUJM2) selected through rigorous screening, for the removal of potentially toxic elements (PTEs; As, Cd, Cu, Ni) and promotion of plant growth under PTE-stress conditions. The dried biomass of the bacterial strain removed PTEs (5 mg L−1) from water by 90.17–94.75 and 60.4–81.41%, whereas live cells removed 87.15–91.69 and 57.5–78.8%, respectively, under single-PTE and co-contaminated conditions. When subjected to a single PTE, the bacterial production of indole-3-acetic acid (IAA) reached the maxima with Cu (67.66%) and Ni (64.33%), but Cd showed an inhibitory effect beyond 5 mg L−1 level. The multiple-PTE treatment induced IAA production only up to 5 mg L−1 beyond which inhibition ensued. Enhanced germination rate, germination index and seed production of lentil plant (Lens culinaris) under the bacterial inoculation indicated the plant growth promotion potential of the microbial strain. Lentil plants, as a result of bacterial inoculation, responded with higher shoot length (7.1–27.61%), shoot dry weight (18.22–36.3%) and seed production (19.23–29.17%) under PTE-stress conditions. The PTE uptake in lentil shoots decreased by 67.02–79.85% and 65.94–78.08%, respectively, under single- and multiple-PTE contaminated conditions. Similarly, PTE uptake was reduced in seeds up to 72.82–86.62% and 68.68–85.94%, respectively. The bacteria-mediated inhibition of PTE translocation in lentil plant was confirmed from the translocation factor of the respective PTEs. Thus, the selected bacterium (Bacillus sp. KUJM2) offered considerable potential as a PTE remediating agent, plant growth promoter and regulator of PTE translocation curtailing environmental and human health risks. Image 1 • Dried/live metal(loid)-resistant Bacillus sp. acts as agent of toxicants' removal. • Synthesizes IAA in contaminated state (single and multiple) and induces plant growth. • Modulation of translocation/retention lowered toxicant levels in plant parts. • Toxicant level in edible part (seed) lied within permissible limits averting risk. • Biomass cuts soil toxic load to harness remedial and agronomic double dividends. [ABSTRACT FROM AUTHOR]

Hierarchical ZnO nanorods were synthesized via mild solvothermal approach followed by calcination at elevated temperatures (i.e. 250 °C and 450 °C) to induce surface defects. The defect induced nanostructures were utilized as resistive devices for low level acetone detection (~10–50 ppm). The porosity and the surface area of ZnO nanorods were seen to increase with increase in calcination temperature as evident from BET results (surface area of 450 °C calcined sample ~55.45 m2/g whereas for un-calcined sample ~38.63 m2/g). The 450 °C sample exhibited excellent acetone sensing (response ~705% at 20 ppm of acetone) with fast response and recovery time (25 s and 31 s respectively) in comparison to the other samples (i.e. 250 °C and un-calcined). The sensing performance was found to improve with increasing calcination temperature which was due to the formation of oxygen vacancies as evident from photoluminescence spectroscopy (enhancement of peak at ~538 nm). A higher surface area coupled with increased oxygen vacancies was responsible for enhanced sensing performance of the calcined nanostructures. The sensor was found to be repeatable and highly selective toward acetone compared to five other volatile organic compounds. Thus, the defect induced ZnO-based sensor shows potential to develop future commercial acetone sensor. [ABSTRACT FROM AUTHOR]

Background: Despite the available clinico-epidemiological evidence of heavy metal-associated respiratory health hazards among metal arc-welders, experimental confirmation of such an association is lacking. Methods: In this study, we recruited 15 metal arc-welders and 10 referent workers without direct exposure. We assessed respiratory health through a questionnaire and spirometry; estimated manganese, nickel and cadmium levels in blood, urine and induced sputum; performed differential counts of sputum leucocytes and measured plasma malondialdehyde (MDA). We used atomic force and scanning electron microscopy to assess the physical property of the alveolar macrophages (AMs) obtained from induced sputum and analysed cell surface deposition of heavy metals using energy dispersion X-ray analysis (EDX). Sputum cellular DNA damage was assessed by DNA-laddering assay. Results: There was a higher body burden of manganese and nickel in the metal arc-welders than the referents. Among major spirometric indices, only the forced mid-expiratory flow rates (FEF25–75) were reduced in the welders compared with the referents (63.4 ± 14.7 vs. 89.2 ± 26.7, p < 0.01); this reduction was associated with both heavy metal levels (β: −41.8, 95% CI: −78.5% to −5.1%) and plasma MDA (−0.37; −0.68 to −0.06). In metal arc-welders, significant physical and morphological changes were observed in AMs through microscopic evaluation while EDX analyses demonstrated higher deposition of heavy metals on the AM cell surface than the referents. We also observed a higher degree of DNA damage in the sputum cells of the exposed workers than the referents. Conclusion: Heavy metal exposure-induced adverse respiratory effects among metal arc-welders are mediated through haematological and cytological interactions. [ABSTRACT FROM AUTHOR]

The aim was to isolate, characterize, and explore potentials of gut bacteria from the earthworm (Metaphire posthuma) and imply these bacteria for remediation of Cu(II) and Zn(II). An extracellular polymeric substance (EPS) producing gut bacteria (Bacillus licheniformis strain KX657843) was isolated and identified based on 16S rRNA sequencing and phylogenetic analysis. The strain showed maximum tolerance of 8 and 6 mM for Cu(II) and Zn(II) respectively. It removed 34.5% of Cu(II) and 54.4% of Zn(II) at 25 mg L−1 after 72 and 96 h incubation respectively. The bacteria possessed a great potential to produce indole acetic acid (38.49 μg mL−1) at 5 mg mL−1L-tryptophan following 12 days incubation. The sterilized seeds of mung beans (Vigna radiata) displayed greater germination and growth under bacterium enriched condition. We observed that the bacterial strain phosphate solubilization ability with a maximum of 204.2 mg L−1 in absence of Cu(II) and Zn(II). Endowed with biosurfactant property the bacterium exhibited 24% emulsification index. The bacterium offered significant potential of plant growth promotion, Cu(II) and Zn(II) removal, and as such this study is the first report on EPS producing B. licheniformis KX657843 from earthworm which can be applied as powerful tool in remediation programs of Cu(II) and Zn(II) contaminated sites. [ABSTRACT FROM AUTHOR]

In this study the multiple metal(loid) (As, Cd, Cu and Ni) resistant bacterium Serratia sp. KUJM3 was able to grow in both single and multiple metal(loid) contaminated wastewater and removed them by 34.93–48.80% and 22.93–32%, respectively. It reduced As(v) to As(III) by 68.44–85.06% in a concentration dependent manner. The strain's IAA production potential increased significantly under both metal(loid)s regime. The lentil (Lens culinaris) seed germination and seed production were enhanced with the exogenous bacterial inoculation by 20.39 and 16.43%, respectively. Under both multi-metal(loid) regimes the bacterial inoculation promoted shoot length (22.65–51.34%), shoot dry weight (33.89–66.11%) and seed production (13.46–35%). Under bacterial manipulation the metal(loid)s immobilization increased with concomitant curtailment of translocation in lentil plant by 61.89–75.14% and 59.19–71.14% in shoot and seed, respectively. The strain biomineralized struvite (MgNH 4 PO 4 ·6H 2 O) from human urine @ 403 ± 6.24 mg L−1. The fertilizer potential of struvite was confirmed with the promotion of cowpea (Vigna unguiculata) growth traits e.g. leaf number (37.04%), pod number (234%), plant wet weight (65.47%) and seed number (134.52%). Thus Serratia sp. KUJM3 offers multiple benefits of metal(loid)s bioremediation, As(V) reduction, plant growth promotion, and struvite biomineralization garnering a suite of appealing environmental applications. [ABSTRACT FROM AUTHOR]

Backgrounds: Hyperuricemia has not yet been established as cardiovascular risk factor. We aimed to study the angiographic severity in patients with coronary artery disease (CAD) and hyperuricemia. Materials and Methods: In this observational cross-sectional study we measured serum uric acid level in 82 patients of CAD who underwent coronary angiography in catheterisation laboratory of our Institution. Severity of CAD was determined on the basis of Gensini score, number of diseased vessels, critical lesions and total occlusions. Results: The prevalence of hyperuricemia in patients with CAD was 42.68% in our study. Hyperuricemia was associated with higher Gensini score (33.33±10.64 vs. 22.90±6.75, p value <0.001), number of critical lesions (1.03±0.84 vs. 0.63±0.72, p value 0.031), total occlusions (0.67±0.47 vs. 0.37±0.48, p value 0.007) and dyslipidemia (63.6% vs. 30.6%, p value 0.003) more frequently compared to normouricemic patients. And also the higher serum uric acid level was correlated with higher Gensini score (beta 0.418, t 4.430, p value <0.001, 95% CI 0.036 and 0.094) and frequent number of total occlusion (beta 0.338, t 3.589, p value 0.001, 95% CI 0.462 and 1.613). Conclusion: Hyperuricemia was associated with higher Gensini score, frequent total occlusions and critical lesions in patients with Coronary Artery Disease compared to patients with normal uric acid level and also it was significantly correlated with higher Gensini score and frequent total occlusions. [ABSTRACT FROM AUTHOR]

Background: Neurocysticercosis (NCC) is a common, widely prevalent parasitic infestation of the central nervous system in children of developing countries leading to neurological morbidities. Objectives: To study the variability of initial clinical presentations and brain imaging findings in children with NCC in the rural population of West Bengal. Methods: A retrospective analysis was done in the Department of Pediatric Medicine, Burdwan Medical College, Burdwan, India from August 2011 to August 2013. Results: Out of 952 admitted children with seizure, 113 children were diagnosed as having NCC (11.9%). Out of them, 62 (54.9%) were boys and 51 (45.1%) were girls. The age of presentation varied from 3 years to 12 years, with mean age 9.4 years. The commonest age of presentation was between 10 to 12 years (n=62; 54.9%). The maximum number of patients were from Burdwan district (n=72; 63.7%) followed by Birbhum (n=25; 22.1%). The commonest initial presentation with seizure (n=93; 82.3 %); partial seizure were present in 76 patients (81.7%). On brain imaging study, the commonest location of lesions was found in the parietal region (n=69; 61.1 %), the right parietal region being more common. Single lesions were found in 102 patients(90.3%). Conclusion: NCC is a major cause of neurological morbidity in children of developing nations and it should be suspected in any children presenting with a first episode of afebrile partial seizure. A screening brain imaging should be performed earlier to prevent undue mortality and morbidity. [ABSTRACT FROM AUTHOR]

This case report describes the findings of a 10-year-old female child admitted with fever and headache for 3 days along with several episodes of vomiting and generalized seizures for 1 day. She regained consciousness 50 minutes after admission with initial treatment, but developed muscle weakness, followed by tetraplegia with areflexia, bilateral facial palsy and respiratory insufficiency. The nerve conduction study(NCV) had evidence of demyelinating neuropathy and the cerebrospinal fluid (CSF) showed albumino-cytological dissociation. These neurologic findings were consistent with the diagnosis of Guillain-Barré syndrome. The patient was treated with immunoglobulin and other supportive cares. Mechanical ventilation was started on day 3 of hospital admission in face of respiratory insuficiency. Recovery, however, was relatively quick and extubation was possible on 6th day. Work up for CNS infection was non-contributory. MRI of brain done during the course, revealed anarchnoid cyst in right temporal region which might have contributed to the episode of unconsciousness, vomiting and convulsion. After two weeks of hospitalization, the patient was discharged from the hospital on wheel chair with satisfectory improvement of powers of facial and limb muscles. When the patient was seen at the outpatient department four weeks after hospital discharge, she was able to walk with help, with normal facial nerve function on both sides. GB syndrome presenting like meningitis; bilateral facial palsy; and co-presence of an archnoid cyst makes this case worth sharing. [ABSTRACT FROM AUTHOR]

Craniofrontonasal dysplasia syndrome (CFND) (Online Mendelian Inheritance in Man database Number 304110), first described as a distinct entity by Professor Michael Cohen from Canada in 1979, is a very rare X-linked inherited disorder characterized by abnormalities of the head and face (cranio-facial area), hands and feet, and certain skeletal bones. Phenotypic expression varies greatly amongst affected individuals, where females are more commonly and generally more severely affected than males. We are presenting a newborn with this rare and peculiar syndrome, probably the first case from India to make physicians aware of this condition, so that more number of cases are being reported to help establishing an uniform clinical diagnostic criteria for CFND in the near future. [ABSTRACT FROM AUTHOR]

Hepatitis A virus (HAV) infection is a benign, self-limited gastrointestinal infection of the children belonging to the developing countries. Extra-intestinal, especially autoimmune hematological manifestations rarely develop during the course of infection in children. We describe two children, aged 8 months and 5 years who developed immune thrombocytopenic purpura (ITP) during the course of otherwise uncomplicated HAV infection. In both children, bleeding secondary to thrombocytopenia was the initial presentation. An 8-month-old infant was anicteric at presentation and HAV infection was discovered during the course of investigations. Both were treated with platelet concentrates and intravenous immunoglobulin therapy successfully. HAV should be included in the differentials in any child (including infants) who presents with ITP, even in the absence of wellrecognized features of the disease. [ABSTRACT FROM AUTHOR]

Tooth eruption normally starts from 6 months of age. Teeth that appear at birth are called natal teeth, whereas, teeth that erupt during the first month of life are called neonatal teeth. Both are uncommon, with the ratio of natal to neonatal is 3:1. Presence of neonatal teeth may lead to complication in mother like painful bitten or bleeding nipples or it may cause complications in babies like difficulty in feeding, pain/distress due to erupting tooth, swallowing of the tooth, repeated trauma to the tip or undersurface of the tongue resulting in Riga-Fede ulceration and rarely aspiration. We are presenting a 15-day-old male baby who admitted in our hospital primarily with excessive crying and poor feeding and on a thorough physical examination revealed an erupting neonatal tooth. Other causes of excessive crying have been excluded. [ABSTRACT FROM AUTHOR]

Klebsiella pneumoniae (K. pneumoniae) causing brain abscess in newborn infants is rare. Presented herein, is a 27-day-old male neonate who developed two frontal lobe abscesses in association with K. pneumoniae sepsis and meningitis. Antibiotic susceptibility testing utilizing the double-disk synergy method (Cefotaxime and Amoxycillin-Clavulanate) confirmed the extended spectrum betalactamase (ESBL) production by the isolate. He was treated simultaneously with antibiotics (Meropenem and Amikacin) and abscess aspiration through the anterior fontanelle, with less than satisfactory outcome. ESBL producing K. pneumoniae brain abscess in neonates is extremely rare in the English literature. Emperical carbapenems and aminoglycoside coverage in neonates with K. pneumoniae sepsis and brain abscess, especially in areas with high rate of ESBL producing bacteria may be warranted. [ABSTRACT FROM AUTHOR]

Myiasis is the invasion of host's tissues by the larval stage (maggot) of non-biting flies. It usually infects domestic and wild animals, but sometimes also affects human and is commonly found in the tropical and subtropical areas. Umbilical myiasis in the neonatal period associated with sepsis is a rare occurrence with few reported cases in the literature. We report a case of a 20-days-old neonate from a rural area of West Bengal, India, presented with neonatal sepsis due to umbilical myiasis caused by larval form of blow fly (Chrysomya megacephala). [ABSTRACT FROM AUTHOR]

Graphical abstract A new pyrazole containing Thiosemicarbazone ligand and its octahedral Co(III) and Ni(II) complexes have been synthesized & characterized. The reported NNS tridentate ligand (HMP z NHex 2) binds with the metal ion via the pyrazolyl tertiary nitrogen, the azomethine nitrogen and the sulphur in its thione/thiol form. The structural conformations of Co(III) and Ni(II) complexes have been established by X-ray studies and DFT calculations of [Co(MP z NHex 2) 2 ]ClO 4 ·1.5H 2 O (I) and [Ni(HMP z NHex 2) 2 ]Cl 2 ·2H 2 O (II). The detailed antimicrobial activities of the title ligand and all the complexes have been reported. Highlights • Syntheses and characterizations of new Thiosemicarbazone ligand and its Co(III) and Ni(II) complexes have been reported. • X-ray crystallography of Complex I and II confirmed the structures of the complexes as envisaged from spectroscopy. • Antimicrobial activities of the complexes have been confirmed them to be the potential antimicrobial agents. Abstract A new pyrazole containing ligand, 5-methyl-3-formylpyrazole-N(4)-dihexylthiosemicarbazone (HMP z NHex 2), and a host of its cobalt(III) and nickel(II) complexes, [Co(MP z NHex 2) 2 ]X·mH 2 O and [Ni(HMP z NHex 2) 2 ]X 2 ·nH 2 O (X = Cl, Br, ClO 4 , BF 4 and NO 3 ; m = 0 for Cl, Br, BF 4 & NO 3 and 1.5 for ClO 4 ; n = 0 for Br, ClO 4 , BF 4 & NO 3 and 2 for Cl), respectively, have been synthesized and characterized by elemental analyses, magnetic measurements (polycrystalline state), 1H NMR (for the ligand and its Co(III) complexes), electronic and IR spectral parameters. All the reported Co(III) and Ni(II) complexes are cationic in nature and behaving as 1:1 and 1:2 electrolytes, respectively, in MeOH. Electronic spectral data of the complexes categorize them as having distorted octahedral coordination geometry. IR spectral features (4000–450 cm−1) specify a monodeprotonated/neutral tridentate (NNS) function of the ligand, HMP z NHex 2 coordinating to the Co(III)/Ni(II) via the pyrazolyl (tertiary) ring nitrogen, azomethine nitrogen and thiolato/thioketo sulfur atom. 1H NMR spectral data (in CDCl 3 at 400 MHz) for the primary ligand and those of its Co(III) complexes are in agreement with the proposition of bonding sites evidenced from IR data. The single crystal X-ray data of I (C2/c (#15); monoclinic) and II (P-1 (#2); triclinic) have confirmed a CoN 4 S 2 and a NiN 4 S 2 octahedral coordination, respectively. The pair of monoprotic/neutral coordinating ligands is more or less orthogonal to each other in the complex species. The data obtained from DFT calculations are reasonably in agreement with the UV–Vis spectral assignment and the structures of the complex species. Although the ligand and the tested metal ion complexes are capable of inhibiting microbial growth, the cobalt complexes can be promoted as better antimicrobial agents. [ABSTRACT FROM AUTHOR]

The microbial infections due to biofilm forming bacterial pathogens are very common in human subjects. The intensive application of antibiotics in integrated disease management strategy has led to increased multidrug resistance incommon pathogens. Thus, indicating need of developing an alternative method for the control of these multidrug resistant pathogens. Present study involves the Moringa oleifera aqueous extract mediated biological synthesis of silver (Ag nanoparticles (NPs)- Avg. size 82.5 nm; zeta potential = −27.9 mV), copper oxide (CuONPs- Avg. size 61 nm; zeta potential = −19.3 mV), iron oxide (FeONPs- Avg. size 83.3 nm; zeta potential = −9.37 mV) and alumina (AlONPs- Avg. size 87.3 nm; zeta potential = −10.9 mV) nanoparticles. Biological nanoparticles were detected by visual observation, spectrophotometric detection followed by zeta potential analysis, nanoparticle tracking analysis, Fourier transform infrared spectrometry and X-ray diffraction analysis. Nanoparticles were further evaluated for their in vitro antimicrobial potential, membrane damage effectiveness, biofilm inhibition activity by MTT assay. Nanoparticles were assessed against human pathogens viz. two Gram-positive (Bacillus subtilis MTCC 441 and Staphylococcus haemolyticus MTCC 3383) and two Gram-negative bacteria (Enterobacter aerogenes MTCC 111 and Salmonella enterica ser. Typhi MTCC 8767). The nanoparticles exhibited akin activity pattern against all pathogens studied i.e. AgNPs > CuONPs > AlONPs > FeONPs. Tested nanoparticles registered lower MIC values and more intensified growth inhibition against Gram-negative bacteria compared to their Gram-positive counterparts. These results pointed out that the M. oleifera mediated nanoparticles can be prospectivelyutilized in the development of alternative antimicrobials against diverse bacterial infections. [Display omitted] • Ecofriendly M. oleifera mediated metal nanoparticle (NP) synthesis method reported. • Antimicrobial potential of nanoparticles were assessed by inhibition assays. • Bactericidal activity was monitored by Time kill assay and biofilm inhibition assay. • Antibacterial activity pattern of NPs was as: AgNPs > CuONPs > AlONPs > FeONPs. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Two new tetranuclear Zn(II) dicyanamide complexes were synthesized. • Complexes are characterized by different spectroscopic techniques. • Crystal structure discloses Zn 4 molecular ensembles reflecting µ 1,5 & µ 1 -dicyanamide bridging propensity. • FMO, ESP and TD-DFT methods were employed to substantiate the experimental results. • In vitro antibacterial and anti-biofilm properties were evaluated. Abstract Two new dicyanamide-interlaced tetranuclear Zn(II)-Schiff-base complexes [Zn 2 (LOMe)(µ - dca- κN 1 κN5)(µ-dca- κN1)] 2 (1) and [Zn 2 (LOEt)(µ - dca- κN 1 κN5)(µ-dca- κN1)] 2 (2) were synthesized by using salicylaldimino type Schiff bases (H 2 LOMe) and (H 2 LOEt) respectively. Schiff base ligands and the complexes were characterized by elemental analyses, powder X-ray diffraction, FT-IR, FT-Raman, 1H NMR, 13C NMR, UV–Vis, TGA and fluorescence spectroscopy. Dicyanamide modulated complexes were structurally characterized by single crystal X-ray diffraction studies. X-ray crystal structure divulges that the two complexes are isostructural. In both the complexes, the Zn1 metal centers fulfill 5-coordinated distorted square pyramidal geometry having ZnN 3 O 2 chromospheres where Schiff bases are mainly trapped in their complete deprotonated dianionic forms[ L ]2−, whereas Zn2 metal center attained distorted octahedral geometry. In both complexes two asymmetric units are connected by double μ 1,5 -dicyanamide ion thus forming Zn 4 -nuclear metal complex. B3LYP/def2-TZVP level of theory (DFT) successfully applied in both complexes. The complexes (1 – 2) exhibit intraligand (π → π*) fluorescence in DMSO solvent with lifetimes in the range 0.66–0.82 ns. In vitro antibacterial, membrane damage assay and anti-biofilm properties of both complexes are evaluated against some important Gram-positive and Gram-negative bacterial strains. Finally, the UV–Vis experimental spectral findings are well rationalized with the electronic distribution of HOMO-LUMO through TD-DFT level of calculations. [ABSTRACT FROM AUTHOR]