Phyco-Nanotechnology: New Horizons of Gold Nano-Factories

Nanoparticles are gaining importance as versatile materials showing novel or advanced characteristics as compared to larger particles. Synthesis of nanoparticles is being done via chemical and physical methods, and it restricts the potential applications in fields like biomedical and agriculture. Among the biological resources, algae have a tremendous role in bioconversion to different particles. Several applications of metal nanoparticles and nanomaterials have emerged in recent past. Among these, gold nanoparticles have their significant role owing to their potential use in nanoelectronics, deoxyribonucleic acid labeling and biosensor development. This review paper focuses on the use of algae for gold nanoparticle synthesis and on its potential and future prospects as well. It can be concluded that various factors like different algae, pH, protocol, time and pigments affect the shape, structure, size and yield of gold nanoparticles synthesized by the algae. Further, potential applications of nanoparticles synthesized by different algae have been reported.

     

Effect of breastfeeding on immunogenicity of oral live-attenuated human rotavirus vaccine: a randomized trial in HIV-uninfected infants in Soweto,South Africa

Objective

To investigate the effect of abstention from breastfeeding, for an hour before and after each vaccination, on the immune responses of infants to two doses of rotavirus vaccine.

Methods

In Soweto, South Africa, mother–infant pairs who were uninfected with human immunodeficiency virus (HIV) were enrolled as they presented for the “6-week” immunizations of the infants. Each infant was randomly assigned to Group 1 – in which breastfeeding was deferred for at least 1 h before and after each dose of rotavirus vaccine – or Group 2 – in which unrestricted breastfeeding was encouraged. Enzyme-linked immunosorbent assays were used to evaluate the titres of rotavirus-specific IgA in samples of serum collected from each infant immediately before each vaccine dose and 1 month after the second dose. Among the infants, a fourfold or greater increase in titres of rotavirus-specific IgA following vaccination was considered indicative of seroconversion.

Findings

The evaluable infants in Group 1 (n = 98) were similar to those in Group 2 (n = 106) in their baseline demographic characteristics and their pre-vaccination titres of anti-rotavirus IgA. After the second vaccine doses, geometric mean titres of anti-rotavirus IgA in the sera of Group-1 infants were similar to those in the sera of Group-2 infants (P = 0.685) and the frequency of seroconversion in the Group-1 infants was similar to that in the Group-2 infants (P = 0.485).

Conclusion

Among HIV-uninfected South African infants, abstention from breastfeeding for at least 1 h before and after each vaccination dose had no significant effect on the infants’ immune response to a rotavirus vaccine.     

Diarrhoea-related hospitalizations in children before and after implementation of monovalent rotavirus vaccination in Mexico

Objective

To assess, by socioeconomic setting, the effect of nationwide vaccination against species A rotavirus (RVA) on childhood diarrhoea-related hospitalizations in Mexico.

Methods

Data on children younger than 5 years who were hospitalized for diarrhoea in health ministry hospitals between 1 January 2003 and 31 December 2011 were collected from monthly discharge reports. Human development indexes were used to categorize the states where hospitals were located as having generally high, intermediate or low socioeconomic status. Annual rates of hospitalization for diarrhoea – per 10 000 hospitalizations for any cause – were calculated. Administrative data were used to estimate vaccine coverage.

Findings

In the states with high, intermediate and low socioeconomic status, coverage with a two-dose monovalent RVA vaccine – among children younger than 5 years – had reached 93%, 86% and 71%, respectively, by 2010. The corresponding median annual rates of hospitalization for diarrhoea – per 10 000 admissions – fell from 1001, 834 and 1033 in the “prevaccine” period of 2003–2006, to 597, 497 and 705 in the “postvaccine” period from 2008 to 2011, respectively. These decreases correspond to rate reductions of 40% (95% confidence interval, CI: 38–43), 41% (95% CI: 38–43) and 32% (95% CI: 29–34), respectively. Nationwide, RVA vaccination appeared to have averted approximately 16 500 hospitalizations for childhood diarrhoea in each year of the postvaccine period.

Conclusion

Monovalent RVA vaccination has substantially reduced childhood diarrhoea-related hospitalizations for four continuous years in discretely different socioeconomic populations across Mexico.     

Recent status of the treatment of stress urinary incontinence

The therapeutic options for management of stress urinary incontinence can be conservative, pharmacological or surgical. The treatment of patients with stress urinary incontinence should be tailored to the individual to optimize care. A multitude of surgical techniques have emerged to treat this condition in recent years. The objective of the present review was to present an overview of current practice in the management of stress urinary incontinence while considering the evidence supporting the clinical effectiveness of these procedures.     

2-Phenylindole and Arylsulphonamide: Novel Scaffolds Bactericidal against Mycobacterium tuberculosis

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Malignant melanoma in a child with giant congenital melanocytic nevus and satellite flekers: A rare entity

Malignant melanomas in the pediatric age are remarkably rare representing 0.9% of various pediatric malignancies. Congenital nevi occur in 1 in 100 newborns, whereas giant congenital melanocytic nevus (GCMN) measuring more than 20 cm is seen in 1 in 20 000 cases. Very few cases of malignant melanoma arising from GCMN have been described in English literature. The risk of developing malignant melanoma from GCMN is believed to be directly proportional to the size of the nevus and varies from 2.6% to 20% depending on the size of nevus. We present a case of malignant melanoma in a 12‐year‐old female child who had a congenital giant nevus and multiple satellite flekers all over the body.     

Retrospective Study of Carfilzomib-Pomalidomide-Dexamethasone in Relapsed/Refractory Multiple Myeloma Patients in a Tertiary Care Hospital in India

Carfilzomib is a second-in class Proteosome Inhibitor and has been approved for Relapsed/Refractory Multiple Myeloma (RRMM). We retrospectively retrieved and analyzed data of KPd combination both biweekly and weekly regimens at our centre from 1 st August 2017 and 31 st May 2020. Sixty-nine patients were treated with KPd with median age of 58 years. Median prior lines of chemotherapy were 2(1-15). Twenty-eight (40.5%) patients underwent autoSCT. Median no. of cycles was 4(1-12) and 3(1-13) with median time to response of 4(2-12) and 2(2-6) months in biweekly and once weekly regimen cohorts respectively. At last follow-up, overall response rate (ORR) was 65.2%{CR-n = 10 (14.5%), VGPR-n = 19 (27.5%), PR-n = 16 (23.2%)} with n = 13(18.8%) patients had PD and relapse was observed in n = 24(34.8%). Thirty (43.4%) patients received maintenance therapy {n = 21(70%)} or autoSCT {n = 9(30%)}. Common toxicities were anemia {n = 11(15.9 %)}, thrombocytopenia (n = 15(21.7%) and neutropenia (n = 16 (23.2%)}, hypertension {n = 28(40.5%)}, peripheral neuropathy (grade1/2) {n = 15(21.7%)}, infections [n = 18(26%) {bacterial [n = 9(13%),viral n = 7(10.1%), fungal n = 8(11.6%)}]. At a median follow-up of 18 months, the estimated median PFS was 11.3 months (95%C.I. 8.3– 14.2) whereas the estimated median OS was 28 months (95%C.I. 20.4-35.5) for the entire cohort. Mortality rate of 2.5% and 10% in two cohorts respectively. Commonest cause of death was PD and sepsis. KPD is a well-tolerated regimen for RRMM, which can be a bridge to ASCT, however with significant side effects.     

The polyphenolic phytoalexin polydatin inhibits amyloid aggregation of recombinant human prion protein

Prion diseases involve misfolded and highly infectious aggregates of prion protein (PrP^Sc) which forms amyloid plaques leading to fatal neurodegeneration. The absence of clinically proven therapeutics makes the discovery of effective remedial interventions a prime concern. Herein, we report novel prion intervention by the polyphenolic phytoalexin, polydatin which binds with moderate affinity to the recombinant protease resistant core of human prion protein, encompassing the sequence 90–231 (rPrP^res) and inhibits its conversion into the highly neurotoxic forms. An extensive evaluation using biophysical techniques revealed that polydatin incubated rPrP^res samples generate off-pathway oligomers having reduced cross-β sheet signature, and relatively smaller in size than the native rPrP^res oligomers. The detailed structural analysis using molecular dynamics simulations elucidated the induction of antagonistic mobilities in the β2–α2 loop, α3 helix and the N-terminal amyloidogenic region of prions. This study puts forward novel prion fibrillogenesis inhibitory potential of polydatin, specifically by stabilizing the N-terminal amyloidogenic region. Collectively our results affirm the importance of polydatin in crippling the prion pathogenesis and may serve as a structural scaffold for designing novel therapeutic agents targeting amyloidogenic transition in prions.

Polydatin is found to be a pharmacologically-significant scaffold that can bind to the rPrP^res repertoire and inhibit its conversion to the highly infectious and neurotoxic PrP^Sc-like form, thus acting like a promising anti-prion drug lead.