Characterization and screening of bacteria from rhizosphere of maize grown in Indonesian and Pakistani soils

Thirty rhizobacteria isolated from maize grown in Pakistani and Indonesian soils were evaluated for their morphological characteristics, nitrogen fixation, P-solubilization, indole acetic acid (IAA) and siderophores production. Nitrogenase activity was detected in nineteen isolates ranging from 21.8-3624 n moles C2H4 produced/h/mg protein. Most of the isolates produced IAA, ten were capable of siderophore production while four were P-solubilizers. Ultrastructural studies of Pseudomonas sp. F14 indicated characteristic rhizospheric colonization within 48 h that was observed to change considerably with the passage of time from few bacteria to micro colonies. Random amplified polymorphic DNA (RAPD) analysis of 30 bacterial strains using 30 oligonucleotide primers resulted in considerable level of genetic diversity, with genetic distance ranging from 2-16%. Indonesian isolates were found to be more diverse as compared to Pakistani isolates. The characterization and screening of rhizobacteria of maize rhizosphere has helped in selection of isolates F7, LS-1, 3.1.1.C, F2, F3 and F13 as superior strains for use as bioinoculant. Moreover isolate F14 identified, as Pseudomonas fulgida by partial 16S rRNA sequence analysis is a novel strain regarding its tremendous potentials for inoculum production to enhance the yield of maize.     

Treatment and Survival Outcome of BRAF-Mutated Metastatic Colorectal Cancer: A Retrospective Matched Case-Control Study

Background

Somatic v-Raf murine sarcoma viral oncogene homolog B (BRAF) mutation, present in approximately 10% of metastatic colorectal cancer (mCRC) cases, is associated with poor prognosis. Patient outcome outside of clinical trials has only been reported in small series. We report real-world data on treatment and survival for BRAF-mutated (MT) patients at a single tertiary center, compared with a matched BRAF wild type (WT) control group.

Paradigm shift in migraine management impacted by COVID-19 pandemic and the role of confounding factors inflicting the change

Objectives:To assess the impact of the COVID-19 pandemic on migraineur’s quality of life and confounding factors.Methods:This is an observational cohort study conducted in Rashid hospital, Dubai Health Authority, UAE. Study was plotted to assess migraine indices in pre-COVID period, pre-pandemic and pandemic periods and to evaluate the pandemic induced paradigm shift in migraine management.Results:Out of 840 migraineurs 201 patients were selected, with an obvious female predominance (78%). Migraine without Aura was found in 70% and Migraine with Aura in 29.9%. Mean MIDAS score during period I, II and II was 22.78, 18.58 and 17.92 respectively indicating certain degree of improvement rather than deterioration during pandemic (p=0.001). Interestingly significant reduction in both migraine frequency and severity from pre-COVID to COVID period was noticed (p=0.01). Parameters like headache days/month, use of abortive therapy and Emergency visits also declined. Chronic migraine (CM) showed more improvement than episodic migraine (EM). Confounding factors like distance working and lack of social/professional stress mainly rendered this change. A modified strategy to handle headache during any pandemic/crisis can ensure quality management of migraine.Conclusion:Migraine patients had a resilient behavior during the COVID pandemic and showed significant improvement of all indices. Confounding factors like distance working played the most favorable role.

Coronavirus disease 2019 (COVID-19) mainly exerts its effect by binding to receptors in the pulmonary epithelium and blood vessels with a special affinity to ACE2 receptors; release of inflammatory cytokines like IL-6 and TNFα; dysregulation of the immune response; dysregulation of the renin–angiotensin–aldosterone system (RAAS); thrombo-inflammation; and direct viral toxicity. ¹ Awareness of its clinical manifestations has developed over couple of years and thousands of researchers have reported their experiences to illuminate the world about this novel disease.A systemic review on neurological manifestations has shown up a wide spectrum of symptoms, including smell disorders (59%), taste disorder (56%), headache (20%), ischemic stroke (5%), encephalopathy (8.8%), intracerebral hemorrhage (0.45%), encephalitis/meningitis (1.4%), myelitis (1.2%), neuropathy (acute like Guillain-Barre-syndrome) (1.2%) and rhabdomyolysis. ² Headaches are encountered mainly in neurology clinics, reportedly these make 33% of neurology clinic visits. ³ With a serious concern, headaches are a major symptom reported during the COVID-19 pandemic. Headache-related issues can be segregated into 2 main categories: (i) already existing headaches that are affected by COVID or (ii) new headaches introduced by the infection itself or protective gadgets. For instance, frontline healthcare workers in all hospitals were mandated to wear personal protective equipment (PPE) while handling COVID-19 patients. Wearing the N95 mask during severe acute respiratory distress syndrome (SARS) epidemic in Singapore (2003) resulted in the occurrence of novel onset face-mask-associated headaches with a prevalence of 37.3%. ⁴ Similarly, amongst medical professionals using the N-95-mask and protective eyewear for an average of 5.7 hours/day, 81% reported de-novo PPE induced headaches and 91% stated aggravation in their pre-existing headaches. However, certain trigger factors, such as sleep deprivation (60.9%), physical stress (29.3%), emotional stress (13.0%), irregular mealtimes (15.2%), and inadequate hydration (39.1%) contributed too. ⁵ Of the primary headaches, migraine is highly prevalent and is the second leading cause of years-lost-to-disability worldwide. ⁶ Pandemic induced changes in the healthcare model impacted considerably on headaches and other chronic disorders. ⁷ Management protocols, patient consultancy, clinic visit frequency, emergency visit criteria, and all other management protocols were modified during the pandemic. Consequentially, individuals’ suffering from migraines intensified. Certain factors, such as stress, infection, fear of catching infection, isolation, limited options of recreation, altered sleep cycle, and wearing PPE, rendered notable changes in the frequency and severity of migraine. However, there were certain factors which positively impacted on migraineurs’ lives.Our objective in this study was to assess the impact of the COVID-19 pandemic on migraineur’s quality of life and confounding factors. Such studies can play a leading role in devising new protocols for migraine management during any crisis in future.     

Dendritic cells are responsible for the capacity of CpG oligodeoxynucleotides to act as an adjuvant for protective vaccine immunity against Leishmania major in mice

Vaccination with leishmanial Ag and CpG oligodeoxynucleotides (ODN) confers sustained cellular immunity and protection to infectious challenge up to 6 mo after immunization. To define the cellular mechanism by which CpG ODN mediate their adjuvant effects in vivo, the functional capacity of distinct dendritic cell (DC) subsets was assessed in the lymph nodes (LNs) of BALB/c mice, 36 h after immunization with the leishmanial antigen (LACK) and CpG ODN. After this immunization, there was a striking decrease in the frequency of the CD11c+B220+ plasmacytoid DCs with a proportionate increase in CD11c+CD8-B220- cells. CD11c+CD8+B220- cells were the most potent producers of interleukin (IL)-12 p70 and interferon (IFN)-gamma, while plasmacytoid DCs were the only subset capable of secreting IFN-alpha. In terms of antigen presenting capacity, plasmacytoid DCs were far less efficient compared with the other DC subsets. To certify that DCs were responsible for effective vaccination, we isolated CD11c+ and CD11c- cells 36 h after immunization and used such cells to elicit protective immunity after adoptive transfer in naive, Leishmania major susceptible BALB/c mice. CD11c+ cells but not 10-fold higher numbers of CD11c- cells from such immunized mice mediated protection. Therefore, the combination of LACK antigen and CpG ODN adjuvant leads to the presence of CD11c+ DCs in the draining LN that are capable of vaccinating naive mice in the absence of further antigen or adjuvant.     

Evaluation of amphotericin B interpretive breakpoints for Candida bloodstream isolates by correlation with therapeutic outcome

One hundred seven Candida bloodstream isolates (51 C. albicans, 24 C. glabrata, 13 C. parapsilosis, 13 C. tropicalis, 2 C. dubliniensis, 2 C. krusei, and 2 C. lusitaniae strains) from patients treated with amphotericin B alone underwent in vitro susceptibility testing against amphotericin B using five different methods. Fifty-four isolates were from patients who failed treatment, defined as death 7 to 14 days after the incident candidemia episode, having persistent fever of >or=5 days' duration after the date of the incident candidemia, or the recurrence of fever after two consecutive afebrile days while on antifungal treatment. MICs were determined by using the Clinical Laboratory Standards Institute (formally National Committee for Clinical Laboratory Standards) broth microdilution procedure with two media and by using Etest. Minimum fungicidal concentrations (MFCs) were also measured in two media. Broth microdilution tests with RPMI 1640 medium generated a restricted range of MICs (0.125 to 1 microg/ml); the corresponding MFC values ranged from 0.5 to 4 microg/ml. Broth microdilution tests with antibiotic medium 3 produced a broader distribution of MIC and MFC results (0.015 to 0.25 microg/ml and 0.06 to 2 microg/ml, respectively). Etest produced the widest distribution of MICs (0.094 to 2 microg/ml). However, none of the test formats studied generated results that significantly correlated with therapeutic success or failure.     

The emerging role of T cell Ig mucin 1 in alloimmune responses in an experimental mouse transplant model

T cell Ig mucin 1 (TIM-1) plays an important role in regulating immune responses in autoimmune and asthma models, and it is expressed on both Th1 and Th2 cells. Using an antagonistic TIM-1-specific antibody, we studied the role of TIM-1 in alloimmunity. A short course of TIM-1-specific antibody monotherapy prolonged survival of fully MHC-mismatched vascularized mouse cardiac allografts. This prolongation was associated with inhibition of alloreactive Th1 responses and preservation of Th2 responses. TIM-1-specific antibody treatment was more effective in Th1-type cytokine-deficient Stat4(-/-) recipients as compared with Th2-type cytokine-deficient Stat6(-/-) recipients. Subtherapeutic doses of rapamycin plus TIM-1-specific antibody resulted in allograft acceptance and prevented the development of chronic allograft vasculopathy. Allograft survival via this treatment was accompanied by a Th1- to Th2-type cytokine switch. Depletion of natural Tregs abrogated the graft-protecting effect of the TIM-1-specific antibody. Importantly, CD4(+)CD25(+) Tregs obtained from long-term survivors had enhanced regulatory activity as compared with naive CD4(+)CD25(+) Tregs. Consistent with this, TIM-1-specific antibody treatment both preserved Tregs and prevented the expansion of alloreactive effector Th1 cells in an alloreactive TCR transgenic adoptive transfer model. These studies define previously unknown functions of TIM-1 in regulating alloimmune responses in vivo and may provide a novel approach to promoting transplantation tolerance.