Rapid visual detection of Mycobacterium tuberculosis DNA using gold nanoparticles

Tuberculosis (TB) is one of the world's deadliest infections caused by Mycobacterium tuberculosis (MTB). Though curable, the disease goes undetected in early stages owing to the lack of rapid, simple, cost-effective, and sensitive detection methods. In this investigation, we describe a procedure which is superior, more sensitive, and easier to handle, as compared to the previously reported, nanoparticle-based visual colorimetric assays for rapid detection of TB DNA, after its PCR amplification. This assay employs plasmonic gold nanoparticles (GNP) as a colorimetric agent and ethanol to promote aggregation of GNPs, thereby specifically detecting the amplified MTB DNA. An unambiguous response was achieved within 3 min after adding the DNA amplicon to the reaction tube. This conclusion was supported by spectroscopic data. The assay is sensitive up to ∼340 femtomole levels of MTB DNA, which was amplified using 0.125 ng μL^-1 of the MTB DNA template. Thus, the technique developed here may be employed as a sensitive screening tool for early diagnosis of TB infection and is valuable for low-resource settings in remote areas, because of its simplicity. This ethanol-based visual TB DNA detection method is more sensitive, and fool-proof as compared to the commonly used salt-based colorimetric TB DNA assays, to the best of our knowledge.

Knowledge and Awareness about Systemic Effects of Periodontal Disease among Medical, Dental and Alternate Medical Practitioners and Their Referral Practice to Periodontists

In the past few decades, many medical professionals and dentists have paid close notice to their own fields, specializing in medicine pertaining to body and oral cavity respectively. Currently, this void is rapidly closing between all medical specialties, in presence of significant findings that supports association between periodontal disease and systemic conditions. Till now, some practitioners are not aware about the specialties of dentistry that results in improper referral practices. There are few studies on referral practice pertaining to periodontist, not with standing the fact that clear and effective communication between all health practitioners is essential for good practice. A cross-sectional study was carried out to assess the knowledge and awareness about systemic effects of periodontal disease among medical, dental and alternate medical practitioners and their referral practice to periodontist in Kanpur city. This cross-sectional study was carried out using self-reported questionnaire, distributed to 560 practitioners of various medical fields from January 2020 to August 2021. A total of 206(36.8%) Medical, 194(34.6%) Dentists and 160(28.6%) alternative practitioners participated in study. More than half participants agreed about relationship between periodontal diseases and Diabetes Mellitus, Cardio-VascularDisease and Adverse Pregnancy Outcomes. Among all 31.3% showed good knowledge level while 2.7% showed perfect level of practitioner's referral practice to periodontist. Dentists had statistically higher level of awareness compared to physicians. Referral practice to periodontist was deficit by medical and alternate medical practitioners despite of fact; they have good knowledge of relationship between periodontal disease and systemic health. Hence, interdisciplinary dental and medical training of practitioners is recommended.

ANN-GA based biosorption of As(III) from water through chemo-tailored and iron impregnated fungal biofilter system

The iron impregnated fungal bio-filter (IIFB) discs of luffa sponge containing Phanerochaete chrysosporium mycelia have been used for the removal of As(III) from water. Two different forms of same biomass viz. free fungal biomass (FFB) and modified free fungal biomass (chemically modified and iron impregnated; CFB and IIFB) have been simultaneously investigated to compare the performance of immobilization, chemo-tailoring and iron impregnation for remediation of As(III). IIFB showed highest uptake capacity and percentage removal of As(III), 1.32 mg/g and 92.4% respectively among FFB, CFB and IIFB. Further, the application of RSM and ANN-GA based mathematical model showed a substantial increase in removal i.e. 99.2% of As(III) was filtered out from water at optimised conditions i.e. biomass dose 0.72 g/L, pH 7.31, temperature 42 °C, and initial As(III) concentration 1.1 mg/L. Isotherm, kinetic and thermodynamic studies proved that the process followed monolayer sorption pattern in spontaneous and endothermic way through pseudo-second order kinetic pathway. Continuous mode of As(III) removal in IIFB packed bed bioreactor, revealed increased removal of As(III) from 76.40 to 88.23% with increased column height from 5 to 25 cm whereas the removal decreased from 88.23 to 69.45% while increasing flow rate from 1.66 to 8.30 mL/min. Moreover, the IIFB discs was regenerated by using 10% NaOH as eluting agent and evaluated for As(III) removal for four sorption–desorption cycles, showing slight decrease of their efficiency by 1–2%. SEM–EDX, pHzpc, and FTIR analysis, revealed the involvement of hydroxyl and amino surface groups following a non-electrostatic legend exchange sorption mechanism during removal of As(III).

High iron-mediated increased oral fungal burden, oral-to-gut transmission, and changes to pathogenicity of Candida albicans in oropharyngeal candidiasis

Background

Aim

Methods

Results

Conclusion

Meniscal Tear at Knee: Repair or Resect? An Early Experience from a University Hospital in Nepal

Background The meniscus plays an important role in maintaining healthy articular cartilage. Meniscus tear, one of the common intra-articular knee lesions, is treated by either debridement or repair. Objective This study aims at identifying the early outcome of meniscus tears treated by debridement or repair. This study also elaborates on the spectrum of meniscal injuries presented in a tertiary care hospital in Nepal. Method A retrospective descriptive cross-sectional study was conducted at Orthopedic Department of Dhulikhel Hospital from February 2018 until January 2020 among patients who underwent knee arthroscopies for meniscal tears treated either by debridement or repair. Patients having intra articular fractures, osteochondral injuries and multi-ligament injuries were excluded. The meniscal tears were classified according to location and type of tear. Those patients who had at least one-year of follow up were evaluated with Lysholm score for functional outcome. Data were compiled and analyzed with Microsoft Excel 2011. Result One hundred and ten cases of meniscal tears were managed over the study period. Ninty-three cases could be traced for outcome evaluation, which included 50 cases of meniscal debridement and 43 cases of meniscal repair. The mean Lysholm score of the patients who received debridement was 81.5 (SD 10.4) and those who received meniscal repair was 84.9 (SD 9.1) (p=0.105). The population distribution was found to be similar in both the groups according to age and sex distribution and associated ligamentous injuries. Conclusion Good functional outcome was seen for meniscal tears managed with debridement or repair in at least one year follow up and could not establish one modality of management better than the other.

Diaspora as a soft power in India’s foreign policy towards Singapore

India’s connections with Southeast Asia are rooted in history in terms of geography, civilization, culture, economy and strategy. These connections became deeper since the 1990s as India initiated the policy of ‘Look East’ that resulted in manifold growth with ASEAN and Singapore. The initiation of ‘Look East Policy’ opened the door for Singaporean Indians for investments and interaction with their motherland. Through the ‘Look East Policy’ the distance between India and ASEAN ended and India was connected with this region and especially Singapore through trade relations. With this policy, India was able to enter this region and this was the chance for the Indian people to revitalize and energize their social and cultural bonds with their motherland (Pande 2017). These relations were further intensified after 2014 as Prime Minister Narendra Modi officially launched ‘Act East Policy’. While ‘Look East Policy’ was launched by India in the backdrop of the critical economic situation, the ‘Act East Policy’ is aimed at strengthening our relations in terms of cultural, political and strategic dimensions. Therefore, this paper aims to study and analyse the role of the Indian diaspora as a soft power for making strong bilateral bonds between India and Singapore with special reference to the political and economic scenario.

Antifungal Effect of Piezoelectric Charges on PMMA Dentures

Candida-associated denture stomatitis is a recurring disease affecting up to 67% of denture wearers. Poly(methyl methacrylate) (PMMA) remains the main material employed in the fabrication of dentures due to its desirable physical, mechanical, and aesthetic properties. However, the improvement of its antimicrobial properties remains a challenge. To address this need, we developed PMMA composite filled with piezoelectric nanoparticles of barium titanate (BaTiO₃) for therapeutic effects. Candida albicans biofilms were cultivated on the surface of the composites under continuous cyclic mechanical loading to activate the piezoelectric charges and to resemble mastication patterns. The interactions between biofilms and biomaterials were evaluated by measuring the biofilm biomass, metabolic activity, and the number of viable cells. To explore the antifungal mechanisms, changes in the expression of genes encoding adhesins and superoxide dismutase were assessed using reverse transcription-polymerase chain reaction. With the addition of piezoelectric nanoparticles, we observed a significant reduction in the biofilm formation and interference in the yeast-to-hyphae transition compared to the standard PMMA. Moreover, we observed that the cyclic deformation of biomaterial surfaces without antifungal agents produced increased biomass, metabolic activity, and a number of viable cells compared to the static/no-deformed surfaces. Cyclic deformation appears to be a novel mechanobiological signal that enables pathogenicity and virulence of C. albicans cells with increased expression of the yeast-to-hyphae transition genes. The outcome of this study opens new opportunities for the design of antifungal dentures for improved clinical service and reduced need for cleaning methods.

Complications of tuberculous meningitis and their effect on outcome in a tertiary care cohort

BACKGROUND: To report the frequency and severity of complications, and their effect on the outcome of tuberculous meningitis (TBM).METHODS: In this retrospective cohort study, the following TBM complications were observed: status epilepticus (SE), hydrocephalus, paradoxical clinical worsening (PCW), hyponatremia, drug-induced hepatitis (DIH), infarction and mechanical ventilation (MV). These were recorded and correlated with stage of meningitis and outcome.RESULTS: A total of 144 patients with TBM (median age 26 years, range 12-75) were included. There were 76 (52.8%) females. The patients were in Stage I (n = 33), Stage II (n = 82) and Stage III (n = 29); 58 had definite TBM. Complications occurred in 128 (88.9%); complications included hydrocephalus (n = 58, 40.3%), hyponatremia (n = 70, 48.6%), infarction (n = 48, 33.3%), DIH (n = 42, 29.2%), SE (n = 16, 18.0%), MV (n = 43, 29.9%) and PCW (n = 24, 16.7%), with variable overlap. By 6 months, 33 patients had died. Death was related to PCW (P = 0.016), hyponatremia (P = 0.03), MV (P = 0.02), infarction (P = 0.03) and the number of complications. Except PCW, most complications occurred during the first month.CONCLUSIONS: In TBM, complications occurred in 128 (88.9%) patients, mainly in the early stages, with variable overlap. Infarction, PCW, hyponatremia and MV were predictive of poor outcome.

The use of eugenol in combination with cefotaxime and ciprofloxacin to combat ESBL-producing quinolone-resistant pathogenic Enterobacteriaceae

AIM

Emergence of extended-spectrum beta-lactamase (ESBL) producing with quinolone-resistant (QR) pathogenic Enterobacteriaceae augmented the need to establish therapeutic options against them. Present study aimed towards determination of synergistic combination of eugenol (EG) with cefotaxime (CTX) and ciprofloxacin (CIP) to combat against this resistance and potentiation of antibacterial drugs by EG against these bacteria.

METHODS AND RESULTS

Synergistic interaction between EG and CTX/CIP (FICI: 0·08-0·5) were observed among ESBL-QR bacteria using checkerboard assay. Approximately, 2- to 1024-fold minimum inhibitory concentration value reduction and 17- to 165 030-fold dose reduction index strongly suggested synergistic interaction between EG and antibiotics. Cell viability assay showed reduction in log₁₀ CFU per ml from 16·6 to 3·1 at synergistic concentration. Scanning electron microscopy further proved disruptive effect of EG on cell architecture. Eugenol and/or its combination also altered genes' expressions that imparted antibiotic resistance by ~1·6 to ~1226 folds.

CONCLUSIONS

Reduced doses of antibiotics, bacterial morphological alterations, efflux pump down regulation, porin over expression and beta-lactamase gene inhibition of ESBL-QR bacteria by EG alone or in combination with CTX/CIP might have reversed antibiotic resistance profile of ESBL-QR bacteria.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provided a molecular insight into action of EG and/with CTX and CIP, which might have potentiated antibiotic's activity against ESBL-QR bacteria.

Iron alters the cell wall composition and intracellular lactate to affect Candida albicans susceptibility to antifungals and host immune response

Fungal pathogen Candida albicans has a complex cell wall consisting of an outer layer of mannans and an inner layer of β-glucans and chitin. The fungal cell wall is the primary target for antifungals and is recognized by host immune cells. Environmental conditions such as carbon sources, pH, temperature, and oxygen tension can modulate the fungal cell wall architecture. Cellular signaling pathways, including the mitogen-activated protein kinase (MAPK) pathways, are responsible for sensing environmental cues and mediating cell wall alterations. Although iron has recently been shown to affect β-1,3-glucan exposure on the cell wall, we report here that iron changes the composition of all major C. albicans cell wall components. Specifically, high iron decreased the levels of mannans (including phosphomannans) and chitin; and increased β-1,3-glucan levels. These changes increased the resistance of C. albicans to cell wall-perturbing antifungals. Moreover, high iron cells exhibited adequate mitochondrial functioning; leading to a reduction in accumulation of lactate that signals through the transcription factor Crz1 to induce β-1,3-glucan masking in C. albicans We show here that iron-induced changes in β-1,3-glucan exposure are lactate-dependent; and high iron causes β-1,3-glucan exposure by preventing lactate-induced, Crz1-mediated inhibition of activation of the fungal MAPK Cek1. Furthermore, despite exhibiting enhanced antifungal resistance, high iron C. albicans cells had reduced survival upon phagocytosis by macrophages. Our results underscore the role of iron as an environmental signal in multiple signaling pathways that alter cell wall architecture in C. albicans, thereby affecting its survival upon exposure to antifungals and host immune response.

Effect of multi-strain probiotic (UB0316) in weight management in overweight/obese adults: a 12-week double blind, randomised, placebo-controlled study

This clinical trial was carried out to assess the effects of multi-strain probiotic capsule (UB0316: Lactobacillus salivarius UBLS-22, Lactobacillus casei UBLC-42, Lactobacillus plantarum, UBLP-40, Lactobacillus acidophilus UBLA-34, Bifidobacterium breve UBBr-01, Bacillus coagulans Unique IS2 5×109 cfu each and fructo-oligosaccharide, 100 mg) on overweight/obesity-related parameters. Ninety subjects (age, 30-65 years; body mass index (BMI), 25-32 kg/m2) were randomised into two groups, i.e. UB0316 (probiotic) and placebo (excipient maltodextrin). They were instructed to take 2 capsules (UB0316 or placebo) per day after meals for 12 weeks. Primary (BMI), and secondary (waist-to-hip ratio: WHR; body weight, body fat; sugar and lipid profile) endpoint measures were evaluated at scheduled visits. Vital signs, physical investigations, quality of life, physician/subjects global assessment and adverse events were also recorded. A total of 71 subjects completed the scheduled study visits and analysis thereof showed that a 12-week UB0316 supplementation significantly reduced BMI (95% CI: -0.64, -0.27; P=0.0001), body weight (95% CI: -1.16, -0.50; P<0.0001), and WHR (95% CI: -0.06, -0.01; P=0.007) from the baseline, compared to placebo. Fat, blood lipid and sugar profile changes were non-significant. UB0316 significantly improved quality of life of overweight/obese individuals. Furthermore, no severe adverse events or abnormal findings were noted during vital, blood and physical examinations. In conclusion, this 12-week trial demonstrates that UB0316 is effective in reducing BMI, body weight and WHR in overweight/obese adults.

MIRO-1 Determines Mitochondrial Shape Transition upon GPCR Activation and Ca2+ Stress

Mitochondria shape cytosolic calcium ([Ca²⁺]_c) transients and utilize the mitochondrial Ca²⁺ ([Ca²⁺]_m) in exchange for bioenergetics output. Conversely, dysregulated [Ca²⁺]_c causes [Ca²⁺]_m overload and induces permeability transition pore and cell death. Ablation of MCU-mediated Ca²⁺ uptake exhibited elevated [Ca²⁺]_c and failed to prevent stress-induced cell death. The mechanisms for these effects remain elusive. Here, we report that mitochondria undergo a cytosolic Ca²⁺-induced shape change that is distinct from mitochondrial fission and swelling. [Ca²⁺]_c elevation, but not MCU-mediated Ca²⁺ uptake, appears to be essential for the process we term mitochondrial shape transition (MiST). MiST is mediated by the mitochondrial protein Miro1 through its EF-hand domain 1 in multiple cell types. Moreover, Ca²⁺-dependent disruption of Miro1/KIF5B/tubulin complex is determined by Miro1 EF1 domain. Functionally, Miro1-dependent MiST is essential for autophagy/mitophagy that is attenuated in Miro1 EF1 mutants. Thus, Miro1 is a cytosolic Ca²⁺ sensor that decodes metazoan Ca²⁺ signals as MiST.

A study of atrial and brain natriuretic peptides in tuberculous meningitis and acute encephalitis

OBJECTIVE

To report atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels in patients with tuberculous meningitis (TBM) and acute encephalitis syndrome (AES), and evaluate their relationship with hyponatraemia.

METHODS

Consecutive patients with TBM and AES were included in the study. Hyponatraemia was categorised as cerebral salt wasting (CSW), syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and a miscellaneous group based on clinical and laboratory criteria. Serum ANP and BNP levels were measured upon hospital admission, at the time of diagnosis of hyponatraemia and upon correction of hyponatraemia. Outcome at 3 months was assessed using the modified Rankin scale (mRS) as good (mRS 2) and poor (mRS >2).

RESULTS

There were 67 patients with TBM and 77 with AES. Hyponatraemia was more common in TBM than in AES (65.7% vs. 27%, P < 0.01). Forty-one (63.1%) patients had CSW, 6 (9.2%) SIADH and 18 (27.7%) had miscellaneous causes of hyponatraemia. During hyponatraemia, ANP (180 ± 45 vs. 106 ± 32 pg/ml, P < 0.01) and BNP (263 ± 118 vs. 163 ± 91 pg/ml, P  0.01) levels were significantly increased compared with baseline, and remained high even after Na+ correction.

CONCLUSION

ANP and BNP levels were increased during hyponatraemia and remained high even after correction of hyponatraemia in TBM and AES, especially in patients with CSW. However, ANP and BNP levels could not be used to differentiate CSW from SIADH.

Prevalence and Intensity of Cornudiscoides Agarwali (Monogenoidea) on the Gills of Day's Mystus (Mystus Bleekeri) in Relation to Some Ecological and Biological Factors from Arunachal Pradesh, India

This work investigated the relationship of host size, seasons, and water quality parameters with the prevalence and intensity of Cornudiscoides agarwali on Mystus bleekeri collected from the Dikrong River in Arunachal Pradesh, India from February 2016 to January 2017. A total of 2760 specimens of C. agarwali were recovered from 114 individuals of M. bleekeri. The levels of mean intensity, but not the prevalence, of infection of C. agarwali were positively correlated with fish host size, peaking in the largest size class (45.20 ± 5.69 parasites/fi sh). The prevalence values had a statistically significant seasonal trend, reaching highest (100 %) during the pre-monsoon season, followed by 91.8% during the post-monsoon period and 87.5 % during the monsoon season. The levels of mean intensity of infection were also dependent on the seasons, reaching significantly higher levels during the pre-monsoon season (42.75 ± 4.18 parasites/fi sh). All water quality parameters measured were within the safety value recommended for freshwater aquaculture. Cornudiscoides agarwali maintained its prevalence above 87.5 % throughout the annual cycle, which means it was able to reproduce year-round in a non-polluted river. This could be an indication of monogenoidean community and population dynamics thriving best under optimum water quality parameters. Also, this article draws the attention of parasitologists and ichthyologists to a taxonomic problem of the misidentification of Mystus spp., and therefore, possibly of their parasitic monogenoids.

Compressive three-dimensional super-resolution microscopy with speckle-saturated fluorescence excitation

Nonlinear structured illumination microscopy (nSIM) is an effective approach for super-resolution wide-field fluorescence microscopy with a theoretically unlimited resolution. In nSIM, carefully designed, highly-contrasted illumination patterns are combined with the saturation of an optical transition to enable sub-diffraction imaging. While the technique proved useful for two-dimensional imaging, extending it to three-dimensions is challenging due to the fading of organic fluorophores under intense cycling conditions. Here, we present a compressed sensing approach that allows 3D sub-diffraction nSIM of cultured cells by saturating fluorescence excitation. Exploiting the natural orthogonality of speckles at different axial planes, 3D probing of the sample is achieved by a single two-dimensional scan. Fluorescence contrast under saturated excitation is ensured by the inherent high density of intensity minima associated with optical vortices in polarized speckle patterns. Compressed speckle microscopy is thus a simple approach that enables 3D super-resolved nSIM imaging with potentially considerably reduced acquisition time and photobleaching.

Mitochondrial Ca2+ Uniporter Is a Mitochondrial Luminal Redox Sensor that Augments MCU Channel Activity

Ca²⁺ dynamics and oxidative signaling are fundamental mechanisms for mitochondrial bioenergetics and cell function. The MCU complex is the major pathway by which these signals are integrated in mitochondria. Whether and how these coactive elements interact with MCU have not been established. As an approach toward understanding the regulation of MCU channel by oxidative milieu, we adapted inflammatory and hypoxia models. We identified the conserved cysteine 97 (Cys-97) to be the only reactive thiol in human MCU that undergoes S-glutathionylation. Furthermore, biochemical, structural, and superresolution imaging analysis revealed that MCU oxidation promotes MCU higher order oligomer formation. Both oxidation and mutation of MCU Cys-97 exhibited persistent MCU channel activity with higher [Ca²⁺]_m uptake rate, elevated mROS, and enhanced [Ca²⁺]_m overload-induced cell death. In contrast, these effects were largely independent of MCU interaction with its regulators. These findings reveal a distinct functional role for Cys-97 in ROS sensing and regulation of MCU activity.

Big Data, Predictive Analytics, and Quality Improvement in Kidney Transplantation: A Proof of Concept

We sought proof of concept of a Big Data Solution incorporating longitudinal structured and unstructured patient-level data from electronic health records (EHR) to predict graft loss (GL) and mortality. For a quality improvement initiative, GL and mortality prediction models were constructed using baseline and follow-up data (0-90 days posttransplant; structured and unstructured for 1-year models; data up to 1 year for 3-year models) on adult solitary kidney transplant recipients transplanted during 2007-2015 as follows: Model 1: United Network for Organ Sharing (UNOS) data; Model 2: UNOS & Transplant Database (Tx Database) data; Model 3: UNOS, Tx Database & EHR comorbidity data; and Model 4: UNOS, Tx Database, EHR data, Posttransplant trajectory data, and unstructured data. A 10% 3-year GL rate was observed among 891 patients (2007-2015). Layering of data sources improved model performance; Model 1: area under the curve (AUC), 0.66; (95% confidence interval [CI]: 0.60, 0.72); Model 2: AUC, 0.68; (95% CI: 0.61-0.74); Model 3: AUC, 0.72; (95% CI: 0.66-077); Model 4: AUC, 0.84, (95 % CI: 0.79-0.89). One-year GL (AUC, 0.87; Model 4) and 3-year mortality (AUC, 0.84; Model 4) models performed similarly. A Big Data approach significantly adds efficacy to GL and mortality prediction models and is EHR deployable to optimize outcomes.

Psychiatric comorbidity in new daily persistent headache: A cross-sectional study

BACKGROUND

New daily persistent headache (NDPH) is a type of chronic daily headache. NDPH can have migrainous (NDPH-CM) or tension-type character (NDPH-CTTH). Recently, NDPH patients have shown to have associated anxiety and depression. We compared anxiety, depressive symptoms, somatization and pain catastrophization among NDPH, healthy controls and patients with chronic low-back pain and between NDPH-CM and NDPH-CTTH.

METHODS

We assessed the study population for depressive symptoms by Patient Health Questionnaire-9, anxiety by Generalized Anxiety Disorder Scale - 7, somatoform disorder using DSM IV (TR) criteria and pain catastrophizing by using Pain Catastrophizing Scale.

RESULTS

Fifty-five patients each with NDPH (mean age 28.24 ± 12.05 years, 45.5% females) and age/sex matched healthy individuals and patients with chronic low-back pain were enrolled. Among NDPH patients, somatoform disorder was seen in 32.7%, severe anxiety in 65.5%, severe depressive symptoms in 40%, significant pain catastrophization in 85.5%. NDPH patients had significantly higher frequency of all psychiatric co-morbidities as compared to healthy controls and patients with chronic low-back pain. NDPH-CM patients had significantly higher frequency of depression and pain catastrophizing behaviour as compared to NDPH-CTTH.

CONCLUSION

Anxiety, depressive symptoms, somatization and pain catastrophizing were significantly more prevalent in NDPH when compared to healthy individuals and patients with chronic low back pain. Such effects should be sought for, as they might contribute to refractoriness to treatment.

SIGNIFICANCE

Anxiety, depressive symptoms, somatization and pain catastrophizing were significantly more prevalent in new daily persistent headache when compared to healthy individuals and patients with chronic low back pain. Such effects should be sought for, as they might contribute to refractoriness to treatment.

Reassessing SERS enhancement factors: using thermodynamics to drive substrate design

Over the past 40 years fundamental and application research into Surface-Enhanced Raman Scattering (SERS) has been explored by academia, industry, and government laboratories. To date however, SERS has achieved little commercial success as an analytical technique. Researchers are tackling a variety of paths to help break through the commercial barrier by addressing the reproducibility in both the SERS substrates and SERS signals as well as continuing to explore the underlying mechanisms. To this end, investigators use a variety of methodologies, typically studying strongly binding analytes such as aromatic thiols and azarenes, and report SERS enhancement factor calculations. However a drawback of the traditional SERS enhancement factor calculation is that it does not yield enough information to understand substrate reproducibility, application potential with another analyte, or the driving factors behind the molecule–metal interaction. Our work at the US Army Edgewood Chemical Biological Center has focused on these questions and we have shown that thermodynamic principles play a key role in the SERS response and are an essential factor in future designs of substrates and applications. This work will discuss the advantages and disadvantages of various experimental techniques used to report SERS enhancement with planar SERS substrates and present our alternative SERS enhancement value. We will report on three types of analysis scenarios that all yield different information concerning the effectiveness of the SERS substrate, practical application of the substrate, and finally the thermodynamic properties of the substrate. We believe that through this work a greater understanding for designing substrates will be achieved, one that is based on both thermodynamic and plasmonic properties as opposed to just plasmonic properties. This new understanding and potential change in substrate design will enable more applications for SERS based methodologies including targeting molecules that are traditionally not easily detected with SERS due to the perceived weak molecule–metal interaction of substrates.

Home visits by community health workers to improve identification of serious illness and care seeking in newborns and young infants from low- and middle-income countries

The objectives of this review were to evaluate the effect of home visits by trained community health workers (CHWs) to successfully identify newborns and young infants (up to 59 days of age) with serious illness and improve care seeking from a health facility. The authors searched the Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE. Abstracts of all articles were read by two authors independently and relevant articles selected. Data were extracted in a pretested questionnaire by two authors independently. Statistical analysis was performed using Review Manager software. A meta-analysis of included randomized controlled trials (RCTs) was carried out. Pooled estimates (risk ratios (RRs) with 95% confidence intervals (CIs)) of the evaluated outcome measures were calculated by the generic inverse variance method. Seven articles were identified for inclusion in the review. None of them compared the diagnosis of serious illness in young infants by health workers to a 'gold standard' diagnosis. Three studies were available for evaluating the ability of CHWs to identify seriously ill young infants/signs of serious illness. These studies suggest that sensitivity to identify serious illness ranged from 33.3 to 90.5% and specificity from 75.61 to 98.4%. For the outcome of improved care seeking from a health facility, after pooling the data from six RCTs with 4760 subjects in the intervention and 4398 subjects in the control arm, there was a significant improvement in care seeking in the home visit arm (RR=1.35; 95% CI=1.15 to 1.58). Moderate quality evidence indicated that home visits by trained CHWs were associated with improved care-seeking for sick young infants from health facilities by appropriate health care providers in resource-limited settings. However, there is a lack of data regarding successful identification of serious illness. Evidence from validation studies supports the implementation of home visits by trained CHWs for improving outcomes in sick newborns and young infants in resource-limited areas. Further well-designed studies evaluating the effect of home visits by CHWs on successful identification of seriously ill newborns and young infants should include verification by a 'gold standard'.

Enhanced resolution of experimental ARDS through IL-4-mediated lung macrophage reprogramming

Despite intense investigation, acute respiratory distress syndrome (ARDS) remains an enormous clinical problem for which no specific therapies currently exist. In this study, we used intratracheal lipopolysaccharide or Pseudomonas bacteria administration to model experimental acute lung injury (ALI) and to further understand mediators of the resolution phase of ARDS. Recent work demonstrates macrophages transition from a predominant proinflammatory M1 phenotype during acute inflammation to an anti-inflammatory M2 phenotype with ALI resolution. We tested the hypothesis that IL-4, a potent inducer of M2-specific protein expression, would accelerate ALI resolution and lung repair through reprogramming of endogenous inflammatory macrophages. In fact, IL-4 treatment was found to offer dramatic benefits following delayed administration to mice subjected to experimental ALI, including increased survival, accelerated resolution of lung injury, and improved lung function. Expression of the M2 proteins Arg1, FIZZ1, and Ym1 was increased in lung tissues following IL-4 treatment, and among macrophages, FIZZ1 was most prominently upregulated in the interstitial subpopulation. A similar trend was observed for the expression of macrophage mannose receptor (MMR) and Dectin-1 on the surface of alveolar macrophages following IL-4 administration. Macrophage depletion or STAT6 deficiency abrogated the therapeutic effect of IL-4. Collectively, these data demonstrate that IL-4-mediated therapeutic macrophage reprogramming can accelerate resolution and lung repair despite delayed use following experimental ALI. IL-4 or other therapies that target late-phase, proresolution pathways may hold promise for the treatment of human ARDS.

Prescribing Pattern of Antidepressants in Children and Adolescents: Findings from the Research on Asia Psychotropic Prescription Pattern

OBJECTIVE

Pharmacotherapy of depression in children and adolescents is complex. In the absence of research into the efficacy and safety of antidepressants in this group of patients, their off-label prescription is common. This paper aimed to illustrate the prescription pattern of antidepressants in children and adolescents from major psychiatric centres in Asia.

METHODS

The Research on Asia Psychotropic Prescription Pattern on Antidepressants worked collaboratively in 2013 to study the prescription pattern of antidepressants in Asia using a unified research protocol and questionnaire. Forty psychiatric centres from 10 Asian countries / regions participated and 2321 antidepressant prescriptions were analysed.

RESULTS

A total of 4.7% antidepressant prescriptions were for children and adolescents. Fluoxetine, sertraline, and escitalopram were the most common antidepressants prescribed for children and adolescents. Almost one-third (30.3%) of prescriptions were for diagnoses other than depressive and anxiety disorders. There was less antidepressant polypharmacy and concomitant use of benzodiazepine, but more concomitant use of antipsychotics in children and adolescents compared with adults.

CONCLUSION

Off-label use of antidepressants in children and adolescents was reported by 40 Asian psychiatric institutions that participated in the study. In-service education and regulatory mechanisms should be reinforced to ensure efficacy and safety of antidepressants in children and adolescents.

Arborization patterns of amygdalopetal axons from the rat ventral pallidum

We previously analyzed the arborization patterns of rat ventral pallidal (VP) axons that coursed caudally to innervate the thalamus and brainstem (Tripathi et al. in Brain Struct Funct 218:1133-1157, 2013). Here, we have reconstructed 16 previously undetected axons from the same tracer deposits that follow a more lateral trajectory. Virtually all 16 axons emanating from the different VP compartments collateralized in the extended amygdala system (EAS) and amygdaloid complex. The most frequent targets of axons from the lateral and medial (VPm) VP compartments were the rostral sublenticular extended amygdala, the extended amygdala (EA), the central nucleus of the amygdala and the posterior part of the basolateral amygdaloid nucleus. In contrast, axons from the rostral extension of the VP preferentially innervated the anterior amygdaloid area, the magnocellular preoptic nucleus, and the anterior part of the basomedial amygdaloid nucleus. We additionally found and reconstructed a single corticopetal axon arising from the VPm. The new results show that both direct and indirect projections from the basolateral complex and EAS to the ventral striatopallidal system are reciprocated by VP projections, and suggest that the systems can be activated simultaneously. The results additionally suggest that the amygdaloid complex and cortex are innervated separately from the VP. Finally, the combination of new and previous data indicate that approximately 84 % of VP axons (88/105) participate in basal ganglia circuits, 15 % (16/105) target the amygdaloid complex, and less than 1 % innervate the cortex.

Rapid amplification of Mycobacterium tuberculosis DNA on a paper substrate

We have amplified DNA from Mycobacterium tuberculosis on a paper substrate in 10 minutes using helicase dependent amplification technique.

Antidepressant Prescription Pattern in the Presence of Medical Co-morbidity: REAP-AD 2013 Study

OBJECTIVE

To evaluate the prescription pattern of antidepressants in patients with medical co-morbidity from major psychiatric centres in Asia.

METHODS

The Research on Asian Psychotropic Prescription Pattern for Antidepressants (REAP-AD 2013) collected data from 42 psychiatric centres in 10 Asian countries and regions. Antidepressant prescriptions of 2320 patients with various psychiatric disorders were evaluated. Of these, 370 patients who had specified medical co-morbidities formed the study cohort.

RESULTS

Escitalopram (20%) and mirtazapine (20%) were the most commonly prescribed antidepressants in patients with medical co-morbidity followed by sertraline (16%), trazodone (15%), and paroxetine (12%). Overall, more than half (52%; 247/476) of prescriptions comprised selective serotonin reuptake inhibitors. Slightly less than two-thirds (63%; n = 233) of patients received at least 1 selective serotonin reuptake inhibitor. In addition, 79% of patients were prescribed only 1 antidepressant. The mean number of antidepressants used per patient was 1.25 (standard deviation, 0.56). There were subtle differences in the most preferred antidepressant across medical illnesses such as diabetes mellitus, liver dysfunction, acid peptic disease, and cerebrovascular disease. Differences were also seen in prescription patterns across different countries.

CONCLUSION

Although selective serotonin reuptake inhibitors formed the bulk of antidepressant prescriptions in the presence of medical co-morbidity, mirtazapine was also commonly used in the presence of medical co-morbidities. Specified medical morbidities do influence the selection of antidepressants.

Increasing Trend of Heterogeneous Vancomycin Intermediate Staphylococcus aureus in a Tertiary Care Center of Northern India

Heterogeneous vancomycin intermediate Staphylococcus aureus (hVISA) strains are increasingly reported, and their association with vancomycin treatment failure is a well-known problem worldwide. A total of 500 clinical isolates of methicillin-resistant S. aureus were screened for hVISA by four different methods from May 2011 to May 2014. The number of strains screened for hVISA from May to April in 2011-2012, 2012-2013, and 2013-2014 were 198, 123, and 179, respectively. hVISA strains were studied by transmission electron microscopy (TEM) for cell wall thickness and also for their ability to form biofilm on a polystyrene microtiter plate. hVISA strains detected by four different methods-brain heart infusion agar with vancomycin with 4 mg/L/gradient plate/macro E-test/and glycopeptide resistance detection (GRD) E test-were as follows: 11.6%/10%/9%, and 9.5% in 2011-2012, 12.1%/9.7%/8.9%, and 10.5% in 2012-2013, and 13.9%/11.7%/11.1%, and 12.8% in 2013-2014, respectively. Population analysis profile-area under curve analysis confirmed hVISA in 4.5% (9/198), 6.5% (8/123), and 6.7% (12/179) in respective years; 24% (7/29) of hVISA isolates were nonsusceptible to daptomycin. TEM showed a significant increase in cell wall thickness of hVISA isolates (p<0.001) with a distinct reduction in their biofilm formation ability.

Glycopeptide and daptomycin susceptibility trends among clinical isolates of methicillin-resistant Staphylococcus aureus in a tertiary care center in North India

Increased vancomycin minimum inhibitory concentration (MIC) levels in Staphylococcus aureus and their association with vancomycin treatment failure are well-known problems. Few studies have recognized progressive increases in glycopeptide MIC levels for S. aureus strains in recent years. This study determined glycopeptide and daptomycin susceptibility among methicillin resistant S. aureus (MRSA) strains. A total of 776 clinical isolates of MRSA recovered from 2009 to 2012 were studied for glycopeptide and daptomycin susceptibility using the E-test method. The vancomycin MIC geometric mean (GM) of the MRSA isolates was 0.923, 0.944, 1.134 and 1.294 mg/L in the years 2009, 2010, 2011 and 2012, respectively, and the trend significantly increased over the years (P < 0.0001). Similarly, the teicoplanin MIC GM was 1.47, 1.49, 1.8 and 2.04 mg/L in the years from 2009 to 2012, respectively (P < 0.0001). MIC shifts were not found for daptomycin (P > 0.232). A significant increase in the MIC for glycopeptides was observed among the clinical MRSA isolates at our center over a 4-year period. However, the daptomycin MIC did not increase in the observed MRSA isolates.

Incidence of diabetes mellitus in a population-based cohort of HIV-infected and non-HIV-infected persons: the impact of clinical and therapeutic factors over time

AIMS

To examine incidence density rate and correlates of incident diabetes mellitus in a cohort of HIV-infected individuals compared with matched non-HIV-infected persons.

METHODS

Data were obtained from the South Carolina Medicaid system and the enhanced HIV/AIDS Reporting System surveillance database for persons ≥ 18 years of age who had been attended to during the period 1994 to 2011. Time-dependent proportional hazards analysis and marginal structural models were used to analyse the data.

RESULTS

A total of 13 632 individuals (6816, 1:1 matched HIV-infected and non-HIV-infected persons; median age 39 years; 57% male) contributed 88 359 person-years of follow-up. Incidence rate of diabetes was higher in the non-HIV-infected group compared with the HIV-infected group (13.60 vs. 11.35 per 1000 person-years). Multivariable hazards analysis suggested a significantly lower risk of incident diabetes among HIV-infected persons treated with combination antiretroviral therapy compared with the matched non-HIV-infected persons (adjusted hazards ratio 0.55; 95% CI 0.46-0.65). Among HIV-infected persons, marginal structural modelling suggested a significantly higher risk of diabetes with cumulative exposure to protease inhibitors over the observation period (adjusted relative risk 1.35; 95% CI 1.03-1.78), but this association was not significant for exposure to non-nucleoside reverse transcriptase inhibitors. Overall, female gender, older age, non-white race/ethnicity, and pre-existing hypertension, dyslipidaemia, obesity and hepatitis C infection were associated with higher risk of diabetes incidence.

CONCLUSIONS

HIV infection may not be independently associated with increased risk of diabetes. Among HIV-infected persons, exposure to protease inhibitor-based regimens may increase the risk of diabetes. Healthcare providers should make every effort to use combination antiretroviral therapy regimens with a better cardiometabolic profile.

Prevalence and molecular characterisation of New Delhi metallo-β-lactamases NDM-1, NDM-5, NDM-6 and NDM-7 in multidrug-resistant Enterobacteriaceae from India

The growing prevalence of carbapenem resistance in Enterobacteriaceae worldwide is a major concern. New Delhi metallo-β-lactamase (NDM)-mediated carbapenem resistance has been identified in Enterobacteriaceae from numerous countries including those of the Indian subcontinent. Currently, seven NDM β-lactamase variants (NDM-1 to -7) have been identified. This study evaluated the detection and molecular characterisation of NDM variants in Enterobacteriaceae at a tertiary care hospital in India. A total of 464 isolates were tested; 57 (12.3%) were resistant or showed reduced susceptibility to imipenem and meropenem. All carbapenem-resistant isolates were blaNDM-positive by PCR, but 13 isolates bore variants that differed in sequence from blaNDM-1. NDM-5, NDM-6 and NDM-7 were identified in two, eight and three isolates, respectively. blaNDM variants were located on plasmids of >100kb with IncF, IncA/C and untypeable replicon types. Genes encoding the 16S rRNA methyltransferases RmtB, RmtC and ArmA as well as those for AmpC β-lactamases were also located on the same plasmids as blaNDM in different combinations. The prevalence of NDM-5 to -7 variants was significantly higher in Escherichia coli (P=0.015) and they were more frequently isolated from the urology ward (P=0.037) than NDM-1. The mortality rate was comparable between patients infected with isolates positive for blaNDM-1 and blaNDM variants [25% (11/44) vs. 23% (3/13)]. Expression of blaNDM variants in E. coli using the same promoter showed that NDM-7 conferred higher resistance to imipenem. The diverse genotypic features of blaNDM indicate rapid evolution of NDM resulting from their wide spread in the Indian subcontinent.

Sociodemographic and clinical profile of homeless mentally ill inpatients in a north Indian medical university

Homeless mentally ill (HMI) persons are a highly vulnerable and socially disadvantaged population, deprived of even the basic minimal human rights. Data on HMI in India is scarce. This retrospective chart review aimed to evaluate socio-demographic, socio-cultural and clinical profile of HMI patients, and to study reasons of homelessness and outcome related variables in these patients. One hundred and forty homeless persons were admitted to the department of psychiatry of a north Indian medical university from February 2005 to July 2011. Of these, one hundred and twenty-seven (90.7%) had psychiatric illness and six had only intellectual disabilities. The majority of HMI persons were illiterate/minimally literate, adult, male, and from low socioeconomic and rural backgrounds. Most of the patients (55.7%) had more than one psychiatric diagnosis. HMI had considerably high rates of co-morbid substance abuse (44.3%), intellectual disabilities (38.6%) and physical problems (75.4%). Most (84.3%) were mentally ill before leaving home and 54.3% left home themselves due to the illness. Most HMI responded to the treatment. After treatment of mental illness, it was possible to reintegrate about 70% of the patients into their families. Families were willing to accept and support them. Untreated/inadequately treated mental illness was the most common reason for homelessness. Easily accessible treatment and rehabilitation facilities at low cost can improve the plight of such patients. Further research in this area is required.

A new approach of real time polymerase chain reaction in detection of vancomycin-resistant enterococci and its comparison with other methods

BACKGROUND

Vancomycin-resistant enterococci (VRE) are third leading cause of nosocomial infection. Therefore, an effective, accurate and early detection of VRE along with their minimum inhibitory concentrations (MICs) is required to initiate appropriate therapy and thus better patient outcome.

OBJECTIVE

To detect VRE by real time quantitative polymerase chain reaction (Q-PCR) and to compare the results with chrom ID (C-ID) VRE and PCR. Further the study also determined the fold change of vanA gene by Q-PCR in different groups of VRE isolates classified on the basis of glycopeptides MIC range.

SUBJECTS AND METHODS

A total of 145 (80 VRE and 65 vancomycin-susceptible enterococci) clinical isolates were included in the study. After the screening of VRE isolates MICs were determined by E-test and agar dilution method. Further VRE was confirmed by vanA and vanB specific PCR and Q-PCR.

RESULTS

The sensitivity and specificity of C-ID VRE was 100% and 95.38%. However, sensitivity and specificity of conventional and Q-PCR were found to be 100%. Conventional and Q-PCR confirmed that our all isolates were vanA type. Mean R value was significantly higher ( P < 0.001) in group I (MIC > 1024 μg/ml) when compared to group II (MIC 512-1024 μg/ml) and group III (MIC < 512 μg/ml) isolates. The mean R was also significantly higher in group II when compared to group III isolates ( P = 0.038).

CONCLUSION

Q-PCR is a rapid technique to detect vanA in enterococci along with their MIC range, thus it might be helpful to decide the treatment modalities of infections caused by VRE.

Helicobacter pylori cagL amino acid polymorphisms and its association with gastroduodenal diseases

CagL is a pilus protein of Helicobacter pylori that interacts with host cellular α5β1 integrins through its arginine-glycine-aspartate (RGD) motif, guiding proper positioning of the T4SS and translocation of CagA. Deletion or sequence variations of cagL significantly diminished the ability of H. pylori to induce secretion of IL-8 by the host cell. Therefore, this study was undertaken to investigate the association of cagL and its amino acid sequence polymorphisms with gastric cancer (GC), peptic ulcer disease (PUD), and non-ulcer dyspepsia (NUD) as there are no such studies from India. In total, 200 adult patients (NUD 120, PUD 30, GC 50) who underwent an upper gastrointestinal endoscopy were enrolled. H. pylori infection was diagnosed by rapid urease test, culture, histopathology, and PCR. The collected isolates were screened for cagL genotype by PCR and assessed for amino acid sequence polymorphisms using sequence translation. The prevalence of H. pylori infection in study population was 52.5%. Most of the isolates were cagL genopositive (86.6%), and all had RGD motif in their amino acid sequences. D58 and K59 polymorphisms in cagL-genopositive strains were significantly higher in GC patients (P < 0.05). Combined D58K59 polymorphism was associated with higher risk of GC (3.8-fold) when compared to NUD. In conclusion, H. pylori cagL amino acid polymorphisms such as D58K59 are correlated with a higher risk of GC in the Indian population. Further studies are required to know the exact role of particular cagL amino acid polymorphisms in the pathogenicity of H. pylori infection.

Imaging local polarization in ferroelectric thin films by coherent x-ray Bragg projection ptychography

We used x-ray Bragg projection ptychography (BPP) to map spatial variations of ferroelectric polarization in thin film PbTiO3, which exhibited a striped nanoscale domain pattern on a high-miscut (001) SrTiO3 substrate. By converting the reconstructed BPP phase image to picometer-scale ionic displacements in the polar unit cell, a quantitative polarization map was made that was consistent with other characterization. The spatial resolution of 5.7 nm demonstrated here establishes BPP as an important tool for nanoscale ferroelectric domain imaging, especially in complex environments accessible with hard x rays.

Expression profile of latent and lytic transcripts of epstein-barr virus in patients with gastroduodenal diseases: a study from northern India

Epstein-Barr virus (EBV) has been shown to be associated with gastric cancer. However, inconsistent findings have been reported regarding the EBV reactivation in gastric cancer and non-carcinomatous gastric epithelium. Therefore, the aim of the study was to investigate the effect of clinicopathological findings on the expression of different transcripts of EBV in patients with gastric cancer, peptic ulcer, and dyspepsia. A total of 200 adult patients (dyspepsia [120], peptic ulcer [30], gastric cancer [50]) undergoing upper gastrointestinal endoscopy were enrolled. EBV infection was diagnosed with non-polymorphic Epstein-Barr nuclear antigen1 (EBNA1) gene based PCR and confirmed by real-time PCR. The transcripts of EBV were detected by real-time RT-PCR. In patients with gastric cancer and peptic ulcer, EBV DNA was detected more often than in those with dyspepsia (P < 0.05). EBNA1 transcript was detected in all EBV positive cases and its expression was neither associated with disease nor with histopathological findings. The expression of BZLF1 was significantly associated with gastric cancer and peptic ulcer compared to dyspepsia (P < 0.01). BZLF1 expression was also found to be higher in Helicobacter pylori infected patients (P = 0.058). Expression of BARF1 and BcLF1 were significantly higher in gastric epithelium of patients having severe grade chronic inflammation (P = 0.05) and gastric atrophy (P = 0.02), respectively. In conclusion, increased expression of lytic transcripts in patients with gastric cancer, peptic ulcer, gastric atrophy, chronic inflammation and H. pylori infection suggests the association of these factors with EBV reactivation.

Quantitative nanoscale imaging of lattice distortions in epitaxial semiconductor heterostructures using nanofocused X-ray Bragg projection ptychography

We imaged nanoscale lattice strain in a multilayer semiconductor device prototype with a new X-ray technique, nanofocused Bragg projection ptychography. Applying this technique to the epitaxial stressor layer of a SiGe-on-SOI structure, we measured the internal lattice behavior in a targeted region of a single device and demonstrated that its internal strain profile consisted of two competing lattice distortions. These results provide the strongest nondestructive test to date of continuum modeling predictions of nanoscale strain distributions.

Epstein-Barr virus DNA load and its association with Helicobacter pylori infection in gastroduodenal diseases

Helicobacter pylori and Epstein-Barr virus (EBV) infections are common worldwide. Although H. pylori infection is a major factor in gastroduodenal diseases, its role in association with EBV infection is unknown.

OBJECTIVE

To study the association of H. pylori infection and EBV DNA load in patients with gastroduodenal diseases.

METHODS

Biopsy samples were collected from 200 adult patients [non-ulcer dyspepsia (NUD) 100, peptic ulcer disease (PUD) 50, gastric carcinoma (GC) 50] undergoing upper gastrointestinal endoscopy. H. pylori infection was diagnosed by rapid urease test, culture, histopathology, PCR and Q-PCR. EBV DNA was detected by non-polymorphic Epstein-Barr nuclear antigen-1 (EBNA-1) gene based Q-PCR.

RESULTS

In patients with GC and PUD, EBV DNA was detected more often than NUD (GC versus NUD = 90% versus 37%, p < 0.001; PUD versus NUD = 70% versus 37%, p < 0.001). The dual prevalence of H. pylori infection and EBV DNA was significantly higher in patients with GC and PUD than in those with NUD. Median copy number of EBV DNA was considerably higher in GC and PUD than NUD (p < 0.01). The copy number of EBV DNA was significantly higher in H. pylori infected patients (p = 0.015). The number of ureA gene copies was also found to be significantly higher in PUD and NUD with presence of EBV DNA. However, in GC no significant difference was seen between EBV positive and negative status.

CONCLUSION

There was a trend for higher EBV DNA load in H. pylori positive individuals suggesting a probable role of H. pylori in modulating the conversion of EBV to its lytic phase.