Proton Distribution Radii of ^{16-24}O: Signatures of New Shell Closures and Neutron Skin

The root mean square radii of the proton density distribution in ^{16-24}O derived from measurements of charge changing cross sections with a carbon target at ∼900A  MeV together with the matter radii portray thick neutron skin for ^{22-24}O despite ^{22,24}O being doubly magic. Imprints of the shell closures at N=14 and 16 are reflected in local minima of their proton radii that provide evidence for the tensor interaction causing them. The radii agree with ab initio calculations employing the chiral NNLO_{sat} interaction, though skin thickness predictions are challenged. Shell model predictions agree well with the data.

Coexistence of blaNDM-1, blaOXA-51, blaOXA-23 and armA in conjunction with novel mutations detected in RND efflux pump regulators in tigecycline resistant clinical isolates of Acinetobacter baumannii

This study has investigated a total of 51 A. baumannii isolates for the prevalence of resistant determinants in tigecycline susceptible and non-susceptible clinical isolates of A. baumannii. Antimicrobial susceptibility testing revealed 74% of isolates were tigecycline resistant. Mutations in RND-efflux pump regulatory genes and the expression of efflux pump genes were measured in tigecycline resistant isolates. There was a strong co-relation between the blaNDM-1 and armA wherein majority of the isolates that are positive for blaNDM-1 have also harbored armA. Compared with TSAB (tigecycline susceptible A. baumannii), TNAB (tigecycline non-susceptible A. baumannii) isolates show increased distribution of blaNDM-1 (p = 0.048), blaIMP-1 (p<0.0001) and blaOXA-51 (p = 0.0029) carbapenemase genes. The variants of RND-efflux pump regulatory genes due to amino-acid mutations in adeS (F12S, K84E, W61R, N268H and Q299R) and adeL (G21R and Q262R) were identified in tigecycline resistant isolates as well as ISAba1 mediated disruption of adeN were observed causing overexpression of adeIJK efflux pump. Additionally, mutations in adeRS were also associated with increased expression of adeABC efflux pump. Besides, TNAB isolates showed significantly (p<0.0001) higher ability of biofilm formation as compared to TSAB isolates. The tigecycline resistance due to mutations in contemporary A. baumannii isolates having a higher ability to form biofilm may pose therapeutic difficulties.

Safety and immunogenicity of a single dose, live-attenuated 'tetravalent dengue vaccine' in healthy Indian adults; a randomized, double-blind, placebo controlled phase I/II trial

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Dengue Tetravalent Vaccine, Live-attenuated Recombinant of Panacea Biotec is a lyophilized vaccine based on novel formulation.

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Dengue Tetravalent Vaccine targets protection against dengue disease caused by all four dengue virus serotypes.

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Dengue Tetravalent Vaccine Phase I/II clinical trial is the first study conducted in an Indian population and proved to be safe and immunogenic.

Background

Dengue fever is the most prevalent mosquito-borne viral disease in the world, with 390 million dengue infections occurring every year. There is an unmet medical need to develop a safe, effective and affordable dengue vaccine against all four Dengue serotype viruses-DENV1, DENV-2, DENV-3 and DENV-4. Panacea Biotec Ltd (PBL) has developed a cell culture-derived, live-attenuated, lyophilized Tetravalent Dengue Vaccine (TDV). Here, in phase I/II study we assessed the safety and immunogenicity of single dose ‘Dengue Tetravalent Vaccine’ in healthy Indian adults.

Methods

In the study, 100 healthy adult volunteers aged 18–60 years were enrolled. The participants were allocated to TDV and placebo groups in 3:1 ratio, i.e. 75 participants to TDV group and 25 participants to the placebo group. Enrolled participants were administered a single dose of 0.5 ml of the test vaccine / placebo by subcutaneous route. Primary outcome for safety included all solicited AEs up to 21 days, unsolicited AEs up to 28 days and all AEs/serious adverse events (SAEs) till day 90 post-vaccination. For immunogenicity assessment the primary outcome was seroconversion & seropositivity rate by PRNT₅₀ to all four serotype till 90 days.

Results

Overall, 100 subjects were vaccinated out of which 8 subjects (5 subjects in vaccine group and 3 subjects in placebo group) dropped out from the study. The most commonly reported solicited local AE was pain and most common solicited systemic AE was headache and fever. No SAE was reported during the study. There was no statistically significant difference between TDV and placebo groups in terms of AEs. Of the 92 subjects who completed all scheduled visits in the study, 59 (81.9%) achieved seroconversion for DENV-1, 56 (77.8%) for DENV-2; 59 (81.9%) for DENV-3 and 57 (79.2%) for DENV-4 in TDV group. The seroconversion rate in the TDV group was statistically significant (p < 0.001) compared to placebo.

Clinical trial registration: CTRI/2017/02/007923.

Immunoglobulin G Antibodies to SARS-CoV-2 Among Healthcare Workers at a Tertiary Care Center in South India

Introduction

Healthcare workers (HCWs) are at risk of exposure to SARS-CoV-2. Seroprevalence in this group may offer insights into trends to monitor and revise strategies to prevent transmission.

Methods

A cross-sectional study was conducted in two phases among healthcare workers at a tertiary care center to detect IgG antibodies to SARS-CoV-2. Seropositivity was calculated during both phases, and possible associations were determined using regression analysis.

Results

A total of 382 and 168 HCWs took part in the two phases, respectively. IgG antibodies were detected in 13 of 382 (3.4%; 95% confidence interval (CI): 2%-5.7%) and 71 of 168 (42.3%) participants in the first and second phases, respectively. Receiving at least one dose of vaccine (p < 0.001) and age (p = 0.028) were factors associated with the presence of antibodies, while gender, job type, exposure to COVID-19 cases, and comorbidities were not associated with seropositivity.

Conclusion

Serosurveys among HCWs may help identify transmission patterns and redesign infection control practices in the healthcare setting.

Rising Minimum Inhibitory Concentration of Azithromycin: A Therapeutic Challenge in Treating Enteric Fever

Introduction: Enteric fever continues to be endemic in the Indian subcontinent carrying with it significant morbidity, despite available antibiotics. With changing trends in antibiotic use, concern for emerging resistance to many common pathogens is very common. Taking enteric fever, as a case in point, there is evidence of increased use of azithromycin and thirdgeneration cephalosporins. Documenting evidence of increasing concentrations of antibiotics, required to inhibit the organism, is necessary to alter the prescribing practice and to adopt course correction. This is required to modify antibiotic policies in health care setups both for the management of antibiotic susceptible and resistant cases of enteric fever. Aim: To document the rising Minimum Inhibitory Concentration (MIC) of azithromycin among Salmonella isolates. Materials and Methods: A cross-sectional study was conducted in Pondicherry Institute of Medical Sciences for a period of seven years (January 2014 to December 2020). A total of 168 clinical isolates from enteric fever cases were tested for drug resistance to azithromycin by disk diffusion as per Clinical and Laboratory Standards Institute (CLSI) guidelines. MIC was estimated using the Epsilometer test. Results were interpreted as per CLSI 2020 guidelines. Spearman’s rank correlation coefficient (r) and twotailed p-values were estimated to note the trend. Results: Out of 168 Salmonella isolates, 65 were Salmonella Typhi and 103 were Salmonella Paratyphi A. MIC of these isolates ranged from 1.5-64 µg/mL and three isolates were resistant to azithromycin with MIC ≥32 µg/mL and nine isolates had a high level of MIC of 24 µg/mL. Disc diffusion test results were consistent with MIC of azithromycin against Salmonella isolates from enteric fever. Regression coefficient for MIC for the given value of zone diameter for 65 Salmonella Typhi isolates was -0.579 (p<0.001, considered highly significant) and -0.475 (p<0.01, considered as significant) for Salmonella Paratyphi A isolates. Rising MIC to azithromycin was observed among Salmonella isolates over a period of seven years. Conclusion: There is a need to monitor the rising trend of MIC, which may pose a therapeutic challenge for treating enteric fever cases in near future. Regular MIC estimation can pre-empt overt resistance. Hence, MIC testing should be routinely done where facilities are available than doing only disk diffusion testing for enteric fever isolates.

Empiric antibiotic and in-vitro susceptibility of urosepsis pathogens: do they match? The outcome of a study from south India

INTRODUCTION

Urosepsis is life threatening, unless treated immediately. Empirical treatment with appropriate antibiotics lowers the risk of a poor outcome. However, with increasing resistance among common uropathogens, there is a need for continuous review of the existing protocol to determine whether there is a correlation between empirical antibiotic therapy and in-vitro susceptibility pattern of the pathogens causing urosepsis.

METHODOLOGY

A prospective study was carried out on 66 confirmed cases of urosepsis from January 2017 to December 2018 after obtaining ethical clearance. Demographic details, risk factors, length of hospital stay, bacteriological profile, empirical antibiotic given, and change in antibiotic following susceptibility report and outcome was recorded.

RESULTS

Among the 66 urosepsis cases 63 of them were started on empiric antibiotic. The correlation between the empirical antibiotic given and the in-vitro antimicrobial susceptibility was found to be significant with a p value < 0.0001. Among the 63 for whom empiric antibiotics was started further escalation of antibiotic was done in 46 patients. The remaining 20% of cases were changed over to a different antibiotic, in line with susceptibility report. The mortality rate was (15.1%) with a confidence interval of (CI = 15 ± 3.5). The association between the risk factors for urosepsis and their effect on mortality rate was analyzed. Diabetes mellitus and chronic kidney disease were identified as important independent risk factors and had direct influence on the mortality rate with significant p value of 0.0281 and 0.0015 respectively.

CONCLUSIONS

A significant correlation was identified between the empirical antibiotic given and in-vitro antibiotic susceptibility pattern.

Risk factors, bacteriological profile and outcome of surgical site infections following orthopaedic surgery

Background and Objectives:

Surgical site infection (SSI) is a challenge for the surgeon. Incidence of SSI reported in literature varies from 0.5% to 15%. Severity of SSI ranges from superficial skin infection to life-threatening condition like septicaemia. It is responsible for increased morbidity, mortality, and economic burden to the hospital in general, and the patient in particular. The aim of this study was to assess the risk factors, bacteriological profile, length of hospitalization, and cost due to orthopaedic SSI in patients admitted to a tertiary care hospital.

Materials and Methods:

This was a prospective case control study. Cases were diagnosed based on CDC definition of nosocomial SSI. All cases were assessed preoperatively, intraoperatively and postoperatively, according to type of surgery, wound class, duration of operation, antimicrobial prophylaxis, use of drain, preoperative hospital stay, causative micro organism, total hospital stay, readmission rates and cost incurred. Age, sex and surgical procedure matched controls without SSI, were also assessed. Chi-square test and Fisher’s exact test were used for analysis. P= <0.05 was considered significant.

Results:

Out of 1023 patients, 47 cases had SSI, with a rate of 4.6%. Cigarette smoking was a risk factor for SSI (P = 0.0035). The most common etiologic agents were Acinetobacter baumannii and Staphylococcus aureus. Incidence of readmission among SSI cases was more compared to controls (P= 0.0001). Costs attributable to SSI (Indian Rupees) was Rs 32,542 (17,054 to 87,514) which was significantly more than those without SSI (P= <0.001).

Conclusion:

Despite latest surgical amenities, meticulous sterilization protocols and pre-operative antibiotic prophylaxis, SSI continues to be present in healthcare settings. The increase in duration of hospital stay due to SSI adds to additional burden to an already resource-constrained healthcare system.

Melioidosis: distinctive clinico-epidemiological characteristics in southern India

As it is increasingly being reported from India, we carried out a prospective study of patients with culture-proven melioidosis from south India, examining clinical, laboratory features, epidemiological data, risk factors, treatments, outcomes at three and six months, and factors associated with mortality.Between 2014 and 2018, 31 cases were identified. Diabetes (83.9%) and alcohol abuse (58.1%) were common risk factors. Musculoskeletal, skin and soft tissue manifestations together constituted 48.4% of presentations, while 29% had pneumonia. During the intensive phase, 74.2% received one of three recommended antibiotic regimes, but 51.6% did not receive continuation treatment. Pneumonia and lack of continuation treatment were independently associated with a high mortality of 25.8%. Hot spots for melioidosis exist in India, and there is considerable diversity of presentation, including skin, soft tissue, musculoskeletal and neurological involvement. High rates of bacteraemia are shown.

Two-Neutron Halo is Unveiled in ^{29}F

We report the measurement of reaction cross sections (σ_{R}^{ex}) of ^{27,29}F with a carbon target at RIKEN. The unexpectedly large σ_{R}^{ex} and derived matter radius identify ^{29}F as the heaviest two-neutron Borromean halo to date. The halo is attributed to neutrons occupying the 2p_{3/2} orbital, thereby vanishing the shell closure associated with the neutron number N=20. The results are explained by state-of-the-art shell model calculations. Coupled-cluster computations based on effective field theories of the strong nuclear force describe the matter radius of ^{27}F but are challenged for ^{29}F.

Association of ABO blood groups with dengue fever and its complications in a tertiary care hospital

CONTEXT:

Dengue fever (DF) has been steadily increasing in India with outbreaks in certain areas taking the proportion of epidemics. Along with secondary dengue, several risk factors predispose to dengue hemorrhagic fever and dengue shock syndrome. Very few studies associating the relationship between dengue and its severity with ABO blood group have been documented.

AIMS:

The aim of this study was to determine the association between distribution of ABO Rh blood groups and DF and DF with thrombocytopenia.

SETTINGS AND DESIGN:

This was a retrospective descriptive study conducted at the clinical laboratory of the department of microbiology.

MATERIALS AND METHODS:

Dengue patients whose case record contained information on blood group were screened for details of blood group and confirmed dengue diagnosis. Randomly 384 case records were selected. These were divided into two groups; Group 1 included DF cases (platelet count >20,000) and Group 2 included DF cases with thrombocytopenia (platelet count <20,000). Control group consisted of patients other than dengue, whose blood grouping had been done; randomly 390 were selected and analyzed.

STATISTICAL ANALYSIS USED:

P value was calculated using the Chi-square test. Odds ratio were calculated using the Fisher's exact test.

RESULTS:

DF was higher in 23% of individuals with AB blood group as compared to 8.5% of controls (P = 0.0004), whereas patients with blood group O were significantly less affected with DF (P = 0.0048). Disease severity was not associated with any of the blood groups.

CONCLUSIONS:

Individuals with AB blood group are more prone to DF, whereas individuals with blood group O are less prone.

Evaluation of loop-mediated isothermal amplification assay for detection of scrub typhus in patients with acute febrile illness presenting to a Tertiary Care Center in Puducherry, India

PURPOSE

Scrub typhus an acute febrile illness has diverse clinical manifestations, which overlap with other febrile illnesses. Due to this reason, it is misdiagnosed, leading to inappropriate treatment, sometimes resulting in fatality. Thus, accurate diagnosis of scrub typhus is important for appropriate treatment. This study evaluated the loop-mediated isothermal amplification (LAMP) assay as a diagnostic test for scrub typhus among patients with fever.

MATERIALS AND METHODS

A total of 50 cases of acute febrile illness clinically resembling scrub typhus, with or without an eschar, or cases of pyrexia of unknown origin were included in the study. Blood samples collected from these cases were subjected to detection of IgM antibodies to Orientia tsutsugamushi by ELISA, conventional groEL polymerase chain reaction (PCR), and the LAMP assay.

RESULTS

Twelve cases had fever for less than a week, and two had fever for more than 3 weeks. IgM antibodies to O. tsutsugamushi were detected in 37 out of 50 samples (74%). LAMP assay was positive in 33 samples (66%). groEL gene-based PCR detected 35 (70%) samples as positive. Two samples negative by LAMP assay were positive by this PCR. Twenty samples collected from patients with dengue, typhoid, and malaria tested by the LAMP assay were negative, indicating its good specificity. LAMP assay and the conventional groEL-based PCR could detect 72.7% and 74.3% of the samples, respectively before the 10^th day after onset of fever, whereas IgM ELISA could detect only 40.5% of the 37 samples.

CONCLUSION

This study suggests that LAMP assay could be a useful diagnostic test for detecting scrub typhus in the acute phase of the illness and a cheaper alternative to other molecular methods in resource poor settings.

Multidrug-resistant Enterobacteriaceae colonising the gut of adult rural population in South India

Background

Multidrug-resistant (MDR) colonisers act as a reservoir for transmission of antibiotic resistance and are a source of infection. Exposure to antibiotics by the commensal flora renders them resistant. Antibiotic consumption and hospitalisation are two major factors influencing this. We studied, antibiotic-resistant bacteria colonising rural adult population who had restricted access to health care and presumably had low consumption of antibiotics.

Aim

Detection of multidrug resistance genes of extended spectrum β-lactamase (ESBL-CTX-M), AmpC β-Lactamase (CIT), Klebsiella pneumoniae carbapenemase (KPC) and New Delhi Metallo β-lactamase (NDM) in Enterobacteriaceae colonising the gut of adult population in a South Indian rural community.

Methodology

Faecal samples of 154 healthy volunteers were screened for Enterobacteriaceae resistant to commonly used antibiotics by standard methods, followed by phenotypic detection of ESBL by double disk synergy method, AmpC by spot inoculation and carbapenemases by imipenem and ethylenediaminetetraacetic acid + imipenem combined E-test strips and modified Hodge test. Polymerase chain reaction was done to detect bla_CTX-M,bla_CIT,bla_KPC-1 and bla_NDM-1 genes coding for ESBL, AmpC, KPC and NDM, respectively.

Results

Colonisation rate of enteric bacteria with MDR genes in the community was 30.1%. However, phenotypically, only ESBL (3.2%) and NDM (0.65%) were detected. While the genes coding for ESBL, AmpC and NDM were detected in 35.6%, 17.8% and 4.4% of the MDR isolates, respectively.

Conclusions

Carriage of MDR strains with a potential to express multidrug resistance poses a threat of dissemination in the community. Awareness for restricted use of antibiotics and proper sanitation can contain the spread of resistant bacteria.

First Spectroscopy of the Near Drip-line Nucleus ^{40}Mg

One of the most exotic light neutron-rich nuclei currently accessible for experimental study is ^{40}Mg, which lies at the intersection of the nucleon magic number N=28 and the neutron drip line. Low-lying excited states of ^{40}Mg have been studied for the first time following a one-proton removal reaction from ^{41}Al, performed at the Radioactive Isotope Beam Factory of RIKEN Nishina Center with the DALI2 γ-ray array and the ZeroDegree spectrometer. Two γ-ray transitions were observed, suggesting an excitation spectrum that shows unexpected properties as compared to both the systematics along the Z=12, N≥20  Mg isotopes and available state-of-the-art theoretical model predictions. A possible explanation for the observed structure involves weak-binding effects in the low-lying excitation spectrum.

Diagnostic utility of bone marrow examination in evaluation of fever: a descriptive study on 98 immunocompetent adults from a tertiary care institute in south India

Five-year clinico-laboratory data from 99 (one HIV seropositive) adults (mean age = 41.3 ± 20.4 years) who underwent bone marrow examination for fever persisting for ≥ 1 week were analysed and correlated with microbiological characteristics. Infections, reactive marrow changes and haematolymphoid malignancies were most commonly associated with fever. A high concordance rate of 71% was noted between aspiration and trephine biopsies. Bone marrow granulomas (BMG) were seen exclusively on sections and were most commonly of tubercular and typhoidal in origin (two Salmonella Typhi, one Salmonella Paratyphi A). The common aetiologies associated with fever and cytopenia(s) were BMG, acute leukaemia and haemophagocytic lymphohistiocytosis (HLH; n = 3). The yield from bone marrow culture was inferior compared to other body fluids. In conclusion, bone marrow histology is superior to smears in the evaluation of prolonged fever. Marrow culture may not be useful in immunocompetent individuals other than if Salmonellosis is suspected.

Evidence for prevalent Z = 6 magic number in neutron-rich carbon isotopes

The nuclear shell structure, which originates in the nearly independent motion of nucleons in an average potential, provides an important guide for our understanding of nuclear structure and the underlying nuclear forces. Its most remarkable fingerprint is the existence of the so-called magic numbers of protons and neutrons associated with extra stability. Although the introduction of a phenomenological spin-orbit (SO) coupling force in 1949 helped in explaining the magic numbers, its origins are still open questions. Here, we present experimental evidence for the smallest SO-originated magic number (subshell closure) at the proton number six in 13-20C obtained from systematic analysis of point-proton distribution radii, electromagnetic transition rates and atomic masses of light nuclei. Performing ab initio calculations on 14,15C, we show that the observed proton distribution radii and subshell closure can be explained by the state-of-the-art nuclear theory with chiral nucleon-nucleon and three-nucleon forces, which are rooted in the quantum chromodynamics.

Strong Neutron Pairing in core+4n Nuclei

The emission of neutron pairs from the neutron-rich N=12 isotones ^{18}C and ^{20}O has been studied by high-energy nucleon knockout from ^{19}N and ^{21}O secondary beams, populating unbound states of the two isotones up to 15 MeV above their two-neutron emission thresholds. The analysis of triple fragment-n-n correlations shows that the decay ^{19}N(-1p)^{18}C^{*}→^{16}C+n+n is clearly dominated by direct pair emission. The two-neutron correlation strength, the largest ever observed, suggests the predominance of a ^{14}C core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay ^{21}O(-1n)^{20}O^{*}→^{18}O+n+n, attributed to its formation through the knockout of a deeply bound neutron that breaks the ^{16}O core and reduces the number of pairs.

Distribution of different genes responsible for invasive characteristics, detection of point mutations in capsular gene wchA and biofilm production among the invasive and non-invasive isolates of Streptococcus pneumoniae

BACKGROUND

Streptococcus pneumoniae continues to cause morbidity and mortality across the globe, with developing countries bearing the brunt of the disease. It is mainly responsible for meningitis, pneumonia and septicaemia primarily in children, elderly and immunocompromised persons. Colonisation and persistence in the human nasopharynx occur during early childhood, and it appears to be prerequisite for invasive pneumococcal disease (IPD). Factors that help in persistent colonisation and subsequent invasion are ill understood. Several virulence factors have been incriminated for nasopharyngeal carriage (NC) as well as for the manifestation of the pathogenesis of IPD.

MATERIALS AND METHODS

This study attempts to characterise the S. pneumoniae isolates through analysing the distribution of different virulence markers such as lytA, ply, pbpA, eno, psaA, amiA, ciaR and wchA among the isolates obtained from disease and NC. A total of 37 isolates which include 14 invasive and 23 non-invasive isolates were investigated by polymerase chain reaction to detect the genes. Eight representative isolates were investigated for mutations in wchA by DNA sequencing that may responsible for capsular variation.

RESULTS

Ply, pbpA, amiA and eno were observed in a greater percentage of invasive isolates than non-invasive isolates though these differences are not statistically significant. Other two genes ciaH and psaA did not show any significant difference between two groups of isolates. Biofilm production was significantly higher in than non-invasive isolates when compared to invasive isolates. Sequence analysis of wchA revealed three significant point mutations or single-nucleotide polymorphisms (SNPs) among the isolates of one particular cluster (cluster III). These SNPs are responsible for a non-synonymous mutation in wchA bringing in an amino acid change in WchA protein, which is a part of the capsule of S. pneumoniae. Notably, all the three isolates present in cluster III had these SNPs and all of them were isolated from ocular infections.

CONCLUSION

The results of our study implies a possible capsular variations among the isolates and this may have an impact on capsular typing.

Quasifree (p, 2p) Reactions on Oxygen Isotopes: Observation of Isospin Independence of the Reduced Single-Particle Strength

Quasifree one-proton knockout reactions have been employed in inverse kinematics for a systematic study of the structure of stable and exotic oxygen isotopes at the R^{3}B/LAND setup with incident beam energies in the range of 300-450  MeV/u. The oxygen isotopic chain offers a large variation of separation energies that allows for a quantitative understanding of single-particle strength with changing isospin asymmetry. Quasifree knockout reactions provide a complementary approach to intermediate-energy one-nucleon removal reactions. Inclusive cross sections for quasifree knockout reactions of the type ^{A}O(p,2p)^{A-1}N have been determined and compared to calculations based on the eikonal reaction theory. The reduction factors for the single-particle strength with respect to the independent-particle model were obtained and compared to state-of-the-art ab initio predictions. The results do not show any significant dependence on proton-neutron asymmetry.

Improving the Diagnosis of Scrub Typhus by Combining groEL Based Polymerase Chain Reaction and IgM ELISA

INTRODUCTION

Scrub typhus, an acute febrile illness, caused by Orientia tsutsugamushi, is an important cause of pyrexia of unknown origin in regions of endemicity. This disease is mostly underdiagnosed or misdiagnosed, the reasons for this being a combination of factors which include clinical manifestations that can mimic other infections, lack of easy and reliable diagnostic methods and variation among strains in endemic areas. Hence, easy and reliable methods of diagnosis will contribute to rapid identification and treatment of the infection.

AIM

The aim of the study was to compare four different methods of detection of scrub typhus and to identify one single test or a combination of tests detecting maximum number of cases.

MATERIALS AND METHODS

One hundred and forty-five suspected scrub typhus cases were included in this study. Duration of fever and presence of eschar in each patient was noted down. Enzyme-Linked Immunosorbent Assay (ELISA) to detect Immunoglobulin M (IgM) antibodies and Polymerase Chain Reaction (PCR) to detect three genes of Orientia, namely, 56 kDa, 16S rRNA, and groEL were done on these samples. The results of each test were analyzed to identify the test picking up maximum number of positive samples. Statistical analysis was performed using Chi-square test. The level of significance was set at p<0.05.

RESULTS

These tests showed that IgM ELISA (93%) and PCR (68%) picked up maximum number of positives. Statistical analysis performed using Chi-square test between the diagnostic assays showed that the p - value <0.001 was significant for IgM ELISA. Among the molecular markers, p-value was significant (<0.001) for groEL PCR. Further analysis of eschar positivity and duration of fever also showed that groEL PCR could detect DNA of the bacterium even in cases with 10 days of fever and this PCR was the best among the molecular markers used to detect the infection.

CONCLUSION

This study suggests that IgM detection by ELISA and conventional groEL PCR, either in combination or alone, depending on the duration of fever, would enhance the diagnosis of scrub typhus.

Nuclear Force Imprints Revealed on the Elastic Scattering of Protons with ^{10}C

How does nature hold together protons and neutrons to form the wide variety of complex nuclei in the Universe? Describing many-nucleon systems from the fundamental theory of quantum chromodynamics has been the greatest challenge in answering this question. The chiral effective field theory description of the nuclear force now makes this possible but requires certain parameters that are not uniquely determined. Defining the nuclear force needs identification of observables sensitive to the different parametrizations. From a measurement of proton elastic scattering on ^{10}C at TRIUMF and ab initio nuclear reaction calculations, we show that the shape and magnitude of the measured differential cross section is strongly sensitive to the nuclear force prescription.

Investigation of the ^{10}Li shell inversion by neutron continuum transfer reaction

This Letter reports a study of the highly debated ^{10}Li structure through the d(^{9}Li,p)^{10}Li one-neutron transfer reaction at 100 MeV. The ^{10}Li energy spectrum is measured up to 4.6 MeV and angular distributions corresponding to different excitation energy regions are reported for the first time. The comparison between data and theoretical predictions, including pairing correlation effects, shows the existence of a p_{1/2} resonance at 0.45±0.03  MeV excitation energy, while no evidence for a significant s-wave contribution close to the threshold energy is observed. Moreover, two high-lying structures are populated at 1.5 and 2.9 MeV. The corresponding angular distributions suggest a significant s_{1/2} partial-wave contribution for the 1.5 MeV structure and a mixing of configurations at higher energy, with the d_{5/2} partial-wave contributing the most to the cross section.

Measurement of Excitation Spectra in the ^{12}C(p,d) Reaction near the η^{'} Emission Threshold

Excitation spectra of ^{11}C are measured in the ^{12}C(p,d) reaction near the η^{'} emission threshold. A proton beam extracted from the synchrotron SIS-18 at GSI with an incident energy of 2.5 GeV impinges on a carbon target. The momenta of deuterons emitted at 0° are precisely measured with the fragment separator (FRS) operated as a spectrometer. In contrast to theoretical predictions on the possible existence of deeply bound η^{'}-mesic states in carbon nuclei, no distinct structures are observed associated with the formation of bound states. The spectra are analyzed to set stringent constraints on the formation cross section and on the hitherto barely known η^{'}-nucleus interaction.

Proton Distribution Radii of ^{12-19}C Illuminate Features of Neutron Halos

Proton radii of ^{12-19}C densities derived from first accurate charge changing cross section measurements at 900A  MeV with a carbon target are reported. A thick neutron surface evolves from ∼0.5  fm in ^{15}C to ∼1  fm in ^{19}C. The halo radius in ^{19}C is found to be 6.4±0.7  fm as large as ^{11}Li. Ab initio calculations based on chiral nucleon-nucleon and three-nucleon forces reproduce the radii well.

Dengue virus infection: Need for appropriate laboratory tests for diagnosis and management of the condition in children during an outbreak

BACKGROUND

Outbreaks of dengue infection occur in several parts of India with clockwork precision closely related to changing seasons. Most recent outbreak in Puducherry occurred between October 2012 and January 2013, affected a sizable pediatric population. A prospective study was done to characterize the demographic, diagnostic and clinical profile of pediatric patients in a tertiary care center in Puducherry.

MATERIALS AND METHODS

Data of patients serologically positive for either dengue NS1 antigen or anti-dengue IgM antibodies were analyzed. Duration of fever, platelet count, complications, risk factors, morbidity and mortality were analyzed.

RESULTS

Among pediatric cases with fever who were screened for NS1/IgM antibody during the recent outbreak, 161 (37.5%) tested positive. NS1 was detected in 85% while 5.5% tested positive for IgM and 3% for IgG. Few (4.9%) tested positive for both NS1 and IgM and 1.2% were positive for both NS1 and IgG. The mean age was 6 years of which 9% were <1-year, the youngest being 1-month old infant. Mean duration of fever was 4 days. Vomiting was associated in 42% of cases. Thrombocytopenia (51%) and hepatomegaly (41%) were two major observations. Among the NS1 positive cases, 49% had thrombocytopenia. IgM alone and NS1 with IgM were associated with thrombocytopenia in 67% and 78% respectively. 14 children had complications of dengue shock syndrome, and four had dengue hemorrhagic fever. Totally, 22 of the children had platelet transfusion. There was no mortality reported among any of these children.

CONCLUSION

Combination of clinical findings and rapid NS1, IgM detection helped in confirming the diagnosis for appropriate management of dengue in children.

Predebridement wound culture in open fractures does not predict postoperative wound infection: A pilot study

BACKGROUND

There is confusion in the current literature regarding the value of obtaining predebridement wound cultures in the management of open fractures with several studies reporting contrasting results. We undertook a pilot study to determine the initial bacterial flora of open fractures in our environment and determine the correlation between subsequent wound infection if any, and the initial bacterial flora.

MATERIALS AND METHODS

Initial/predebridement wound swabs were obtained for 32 patients with open fractures. Patients underwent a debridement of the open wound and preliminary stabilization of fracture in the operating room within 24 h. Postdebridement wound cultures were obtained at 48 h and repeated subsequently, if indicated, during the follow-up period. The antibiotic therapy was modified based on the culture reports.

RESULTS

Initial wound swab culture showed bacterial contamination in 18 patients (56%); 14 patients (44%) developed an infection in the immediate postoperative period or during follow-up. Age, gender, co-morbid medical condition, delay in presentation, and grade of open fracture were not found to be predictors of postoperative infection. No patient had an infection with the same organism, which was present in the initial culture.

CONCLUSION

The findings of this study suggest that the initial flora are not the infecting organisms in the open fracture wounds, and predebridement wound cultures have no value in predicting postdebridement wound infection.

Simultaneous gut colonisation and infection by ESBL-producing Escherichia coli in hospitalised patients

BACKGROUND

Extended spectrum betalactamase (ESBL)-producing organisms are a major cause of hospital-acquired infections. ESBL-producing Escherichia coli (E. coli) have been recovered from the hospital environment. These drug-resistant organisms have also been found to be present in humans as commensals. The present investigation intended to isolate ESBL-producing E. coli from the gut of already infected patients; to date, only a few studies have shown evidence of the gut microflora as a major source of infection.

AIMS

This study aimed to detect the presence of ESBL genes in E.coli that are isolated from the gut of patients who have already been infected with the same organism.

METHODS

A total of 70 non-repetitive faecal samples were collected from in-patients of our hospital. These in-patients were clinically diagnosed and were culture-positive for ESBL-producing E. coli either from blood, urine, or pus. Standard microbiological methods were used to detect ESBL from clinical and gut isolates. Genes coding for major betalactamase enzymes such as bla CTX-M , bla TEM, and bla SHV were investigated by polymerase chain reaction (PCR).

RESULTS

ESBL-producing E. coli was isolated from 15 (21 per cent) faecal samples of the 70 samples that were cultured. PCR revealed that out of these 15 isolates, the bla CTX-M gene was found in 13 (86.6 per cent) isolates, the bla TEM was present in 11 (73.3 per cent) isolates, and bla SHV only in eight (53.3 per cent) isolates. All 15 clinical and gut isolates had similar phenotypic characters and eight of the 15 patients had similar pattern of genes (bla TEM, bla CTX-M, and bla SHV) in their clinical and gut isolates.

CONCLUSION

Strains with multiple betalactamase genes that colonise the gut of hospitalised patients are a potential threat and it may be a potential source of infection.

Evidence of soft dipole resonance in ^{11}li with isoscalar character

The first conclusive evidence of a dipole resonance in ^{11}Li having isoscalar character observed from inelastic scattering with a novel solid deuteron target is reported. The experiment was performed at the newly commissioned IRIS facility at TRIUMF. The results show a resonance peak at an excitation energy of 1.03±0.03 MeV with a width of 0.51±0.11 MeV (FWHM). The angular distribution is consistent with a dipole excitation in the distorted-wave Born approximation framework. The observed resonance energy together with shell model calculations show the first signature that the monopole tensor interaction is important in ^{11}Li. The first ab initio calculations in the coupled cluster framework are also presented.

Polyarthritis and massive small bowel bleed: An unusual combination in scrub typhus

Scrub typhus is an acute febrile illness caused by the intracellular parasite Orientia tsutsugamushi. Although most cases present with mild symptoms and signs and recover spontaneously, some cases can be severe with multi-organ dysfunction and a protracted course, which may be fatal if left untreated. Apart from fever and constitutional symptoms, atypical presentations allow this disease to mimic several common conditions. We report a case of scrub typhus in an 18-year-old male who presented with severe polyarthritis involving all large joints and a massive lower gastrointestinal bleed from ulcers in the terminal ileum, secondary to vasculitis in the small bowel. This combination of pathologies has not previously been reported in cases of scrub typhus. The patient improved following surgical intervention and specific anti-rickettsial therapy with azithromycin.