Evaluation of the TB-LAMP assay for the rapid diagnosis of pulmonary tuberculosis in Northern India

SETTING

A tertiary care hospital in North India.

OBJECTIVE

To evaluate a commercial kit-based loop-mediated isothermal amplification (TB-LAMP) assay for the diagnosis of pulmonary tuberculosis (PTB).

DESIGN

A total of 530 patients presenting with PTB symptoms were enrolled and one sputum sample was collected from each patient. The TB-LAMP assay (Loopamp™ MTBC Detection kit) was performed on the raw sputum sample. The remaining sample was used for smear microscopy and mycobacterial culture. A cartridge-based nucleic acid amplification test (NAAT, Xpert® MTB/RIF assay) was also performed on the processed pellet.

RESULTS

The sensitivity and specificity of the TB-LAMP assay in culture-positive samples obtained from 453 patients presenting with PTB symptoms (77 specimens were excluded) were respectively 100% (95%CI 94.7-100) and 99.2% (95%CI 97.8-99.8). The sensitivity and specificity of Xpert in culture-positive samples were respectively 82.6% (95%CI 71.5-90.6) and 94.9% (95%CI 92.2-96.8). A concordance of 0.75 was obtained between the two NAATs (TB-LAMP assay and Xpert) using the κ statistic.

CONCLUSION

The TB-LAMP assay showed high sensitivity and specificity with limited requirement of testing infrastructure, and is thus a promising diagnostic tool for TB diagnosis in resource-poor settings.

MIND Diet Associated with Reduced Incidence and Delayed Progression of ParkinsonismA in Old Age

BACKGROUND

In old age, motor impairments including parkinsonian signs are common, but treatment is lacking for many older adults. In this study, we examined the association of a diet specifically developed to promote brain health, called MIND (Mediterranean-DASH Diet Intervention for Neurodegenerative Delay), to the incidence and progression of parkinsonism in older adults.

METHODS

A total of 706 Memory and Aging Project participants aged 59 -97 years and without parkinsonism at baseline were assessed annually for the presence of four parkinsonian signs using a 26-item modified version of the United Parkinson's Disease Rating Scale. Incident parkinsonism was defined as the first occurrence over 4.6 years of follow-up of two or more parkinsonian signs. The progression of parkinsonism was assessed by change in a global parkinsonian score (range: 0-100). MIND, Mediterranean, and DASH diet pattern scores were computed based on a validated food frequency questionnaire including 144 food items. We employed Cox-Proportional Hazard models and linear mixed models, to examine the associations of baseline diet scores with incident parkinsonism and the annual rate of change in global parkinsonian score, respectively.

RESULTS

In models adjusted for age, sex, smoking, total energy intake, BMI and depressive symptoms, higher MIND diet scores were associated with a decreased risk of parkinsonism [(HR=0.89, 95% CI 0.83-0.96)]; and a slower rate of parkinsonism progression [(β= -0.008; SE=0.0037; p=0.04)]. The Mediterranean diet was marginally associated with reduced parkinsonism progression (β= -0.002; SE=0.0014; p=0.06). The DASH diet, by contrast, was not associated with either outcome.

CONCLUSION

The MIND diet created for brain health may be a associated with decreased risk and slower progression of parkinsonism in older adults.

Pesticides exposure through environment and risk of pre-term birth: a study from Agra city

Pre-term birth is an increasingly prevalent complex condition with multiple risk factors including environmental pollutants. Evidences linking organochlorine pesticides with adverse pregnancy outcomes are inconsistent for link between organochlorine pesticides and adverse pregnancy outcomes. We performed a case-control study of 50 cases of full-term births and 40 cases of pre-term births in this study. Placental organochlorine pesticides like metabolites of dichlorodiphenyltrichloroethane that is, (p,p-DDE, p,p-DDT and o,p-DDD) and isomers of hexachlorocyclohexane (α, β, γ and δ HCH) were analyzed by gas chromatography. Although the mean levels of pesticide were found higher in the placenta of the women with pre-term delivery cases placentas, but only α-HCH, total-HCH, p,p-DDE and total-DDT were found statistically significant. It was observed that pesticide exposed women were approximately 1.7 times more likely to deliver pre-term baby as compare to pregnant women that were not exposed to any pesticides. We also observed that increasing maternal age reduced the risk of having pre-term birth (OR = 0.99). Among all pesticides, α-HCH was found to be strongest isomer to induce premature baby birth (p < 0.001). This study found that pregnant women's age and chronic disease, baby's weight at the time of birth and α-HCH were important risk factors for pre-term births.

Elucidating immunometabolic targets in glioblastoma

Immunometabolism has recently emerged on the forefront of cancer research as a new avenue to potentially develop more effective and targeted treatment options. Several pathologically altered metabolic targets across various cancer types have been identified, including lactate in aerobic glycolysis; tryptophan in amino acid metabolism; and arginine in the urea cycle. Numerous advancements have improved our understanding of the dual function of these targets in influencing immune functions as an auxiliary function to their well-established metabolic role. This paper provides a comprehensive overview of immunometabolism research and attempts to provide insight into potential immunometabolic targets in glioblastoma for the purpose of future development and study of targeted therapies.

GenoType MTBDRplus assay for screening and characterization of isoniazid and rifampicin resistance-associated mutations in multidrug-resistant Mycobacterium tuberculosis from India

Multidrug resistant tuberculosis (MDR-TB) is rising and the World Health Organization has recommended the line probe assay (LPA) for screening. In this study we assess LPA at a tertiary care centre from North India in 1758 samples from suspected MDR-TB cases. All smear-positive and/or Mycobacterium tuberculosis culture confirmed cases (n = 1170) were subjected to the GenoType-MTBDR assay. Amongst these the majority were retreatment cases, smear-positive at diagnosis (n = 637). An MDR prevalence of 7·8% was observed with the highest cases reported amongst MDR contacts (33·3%). The most common rifampicin resistance encoding mutation seen overall and in individual patient groups was H531L (53·3%). A higher prevalence of H526D mutation was observed in retreatment cases, smear-positive at 4 months of anti-tubercular therapy vs other patient groups (P = 0·052). The most common mutation encoding isoniazid resistance was S315T1 in the katG (79·9%) and C-15T in the inhA gene (91·1%). Thirty rifampicin and nine isoniazid resistant isolates had wild type gene deletion but no detectable mutation by LPA. Although LPA is a practical and rapid screening method for most mutations expected to result in MDR-TB, we observed that it only detects the known major mutations in specific genes. Such studies can provide the knowledge required to formulate customized strips based on prevalent mutations in our region and in specific patient groups.

SIGNIFICANCE AND IMPACT OF THE STUDY

To the best of our knowledge this is the largest study evaluating the GenoType-MTBDR line probe assay from India. We have studied the prevalence of mutations encoding rifampicin and isoniazid resistance in different patient groups based on criteria for multidrug resistance (MDR) suspicion. The translational impact of this study is in the design of customized country- or region-wise line probe assay strips. The identification of a few mutations in particular patient groups and the detection of wild type deletion mutants with no observable mutations both point toward the need for such customization enabling us to combat the rising trend of MDR tuberculosis.

Time-to-Event Analysis of Polatuzumab Vedotin-Induced Peripheral Neuropathy to Assist in the Comparison of Clinical Dosing Regimens

Polatuzumab vedotin, an antibody-drug conjugate containing monomethyl auristatin E, was associated with an incidence of grade ≥2 peripheral neuropathy (PN) of 55-72% in patients with indolent non-Hodgkin lymphoma in a phase II study, when dosed 1.8-2.4 mg/kg every 3 weeks until progression or for a maximum of 17 cycles. To quantify the correlation of conjugate exposure and treatment duration with PN risk, a time-to-event model was developed using data from phase I and II studies. The model suggested that PN risk increased with conjugate exposure and treatment cycles, and a trend for increased risk with body weight and albumin concentration. When capping the treatment duration to six to eight cycles, the risk ratio of a dose of 2.4 mg/kg vs. 1.8 mg/kg was ≥1.29; the predicted incidence of grade ≥2 PN at 1.8-2.4 mg/kg dose levels was 17.8-37.2%, which is comparable with other antimicrotubule agents for lymphoma treatment.

Correlation between in vitro and in vivo antimalarial activity of compounds using CQ-sensitive and CQ-resistant strains of Plasmodium falciparum and CQ-resistant strain of P. yoelii

Present efforts have been made to establish a correlation between in vitro and in vivo antimalarial activity using MIC, IC₅₀ and IC₉₀ values against CQ-sensitive (3D7) and CQ-resistant (K1) strains of Plasmodium falciparum and in vivo activity against Plasmodium yoelii. The method of discriminant function analysis (DFA) was applied to analyze the data. It was observed that in vitro IC₉₀ values against both 3D7 and K1 strains (p < 0.001) have strong correlation with in vivo curative activity. The respective IC₅₀ and IC₉₀ values of compounds, which cured mice (i.e., animals did not show recrudescence of parasitemia even after 60 days posttreatment), ranged between 3 and 14 nM and 14 and 186 nM against 3D7 and between 9 and 65 nM and 24 and 359 nM against the K1 strain of P. falciparum. Whereas the IC₅₀ and IC₉₀ values of compounds which exhibited in vivo suppressive activity in mice ranged between 10 and 307 nm and 61 and >965 nM, respectively, against 3D7 and 75 and >806 nm and 241 and >1232 nM against the K1 strain of P. falciparum. The findings suggest that IC₉₀ values against both 3D7 and K1 strains (p < 0.02) are the main contributors for the prediction of in vivo curative activity of a new molecule. Apart from this, a reasonable correlation between MIC and IC₅₀ values of compounds has also been established.

Abstract P2-04-27: CTLA-4 and PD-1 checkpoint inhibitors enhance individually tailored adaptive anti-tumor immune responses to overcome tumor immunosuppression and effectively treat triple-negative breast cancer

Despite a lack of unifying drivers in Triple-Negative Breast Cancer (TNBC), our lab and others have uncovered that these cancers have elevated expression of inflammatory genes and immunosuppressive molecules (i.e. PD-L1), as well as elevated numbers of infiltrating immune cells (including CD8+ T-cells and Foxp3+ T-regulatory cells) which suggests the therapeutic potential for single and combinations of checkpoint blockade antibodies. While early trials with PD-1 inhibitors have been encouraging for TNBC, only a fraction of treated patients respond to this therapy. To test and define the mechanisms that govern responses, we explored the utility and mechanistic basis of both PD-1 and CTLA-4 inhibition in generating tumor-specific immunity in an established murine model of TNBC.

Consistent with patient samples, we found TNBC tumors from our model exhibited elevated PD-1+ expressing CD8+ T-cell infiltrates, Foxp3+ T-regulatory cell infiltrates (~66% of CD4+ TILs), as well as highly elevated tumor cell expression of PD-L1. We also found that while TNBC cells were easily killed by T-cell in vitro, TNBC tumors were highly immuno-suppressive and resistant to antigen-specific T-cell attack in vivo, even after adoptive transfer of up to 5x10E6 tumor-specific T-cells.

However, we found that both CTLA-4 and PD-1 antibodies could curtail this immunosuppression to different degrees and through alternate mechanisms. Specifically, we found that CTLA-4 antibody mediated anti-tumor immunity through the elimination and blockade of Foxp3+ T-regulatory cells in the tumor microenvironment, which allow for potent T-cell expansion. Conversely, PD-1 antibodies elicited anti-tumor immunity through blockade of PDL1/PD1 signaling between tumor cells and T-cells in the TNBC tumor microenvironment that allowed for a more modest expansion of individually tailored T-cell specific clones in vivo.

Strikingly, the combination of these antibodies and their alternate mechanisms of action resulted in greatly enhanced anti-tumor responses and led to regression of ~80% of tumors. This was accompanied by an augmented infiltration of T-cells into the tumor microenvironment and significantly enhanced systemic tumor-specific T-cell responses, which appear to be emergent properties of dual CTLA-4/PD-1 antibody treatment.

However, we found that these treatments did not expand a common tumor-specific T-cell clone, despite adoptive transfer of identical tumor-specific immunodominant T-cells into mice after tumor implantation. Thus, despite our use of a highly homogeneous model utilizing genetically identical mice implanted with an identical tumor line bearing a unique tumor antigen under identical conditions, the tumor-specific T-cell responses were highly unique for each individual tumor. Collectively, our study suggest that dual blockade could be an effective therapeutic clinical strategy against TNBC and further suggest the utility of monitoring systemic immune response and TCR expansion of TILs as the most useful correlates in clinical studies utilizing CTLA-4 and PD-1 antibodies.

Citation Format: Hartman ZC, Crosby EJ, Wei J-P, Yang X-Y, Lei G-J, Wang T, Liu C-X, Agarwal P, Morse MS, Lyerly HK. CTLA-4 and PD-1 checkpoint inhibitors enhance individually tailored adaptive anti-tumor immune responses to overcome tumor immunosuppression and effectively treat triple-negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-04-27.

Design, synthesis and in vitro antiplasmodial activity of some bisquinolines against chloroquine-resistant strain

A series of novel bisquinoline compounds comprising N¹ -(7-chloroquinolin-4-yl) ethane-1,2-diamine and 7-chloro-N-(2-(piperazin-1-yl)ethyl)quinolin-4-amine connected with 7-chloro-4-aminoquinoline containing various amino acids is described. We have bio-evaluated the compounds against both chloroquine-sensitive (3D7) and chloroquine-resistant (K1) strains of Plasmodium falciparum in vitro. Among the series, compounds 4 and 7 exhibited 1.8- and 10.6-fold superior activity as compared to chloroquine (CQ; IC₅₀  = 0.255 ± 0.049 μm) against the K1 strain with IC₅₀ values 0.137 ± 0.014 and 0.026 ± 0.007 μm, respectively. Furthermore, compound 7 also displayed promising activity against the 3D7 strain (IC₅₀  = 0.024 ± 0.003 μm) of P. falciparum when compared to CQ. All the compounds in the series displayed resistance factor between 0.57 and 4.71 as against 51 for CQ. These results suggest that bisquinolines can be explored for further development as new antimalarial agents active against chloroquine-resistant P. falciparum.

Mycetoma: An Update

Mycetoma is a localized chronic, suppurative, and deforming granulomatous infection seen in tropical and subtropical areas. It is a disorder of subcutaneous tissue, skin and bones, mainly of feet, characterized by a triad of localized swelling, underlying sinus tracts, and production of grains or granules. Etiological classification divides it into eumycetoma caused by fungus, and actinomycetoma caused by bacteria. Since the treatment of these two etiologies is entirely different, a definite diagnosis after histopathological and microbiological examination is mandatory, though difficult. Serological test exists but is not so reliable; however, molecular techniques to identify relevant antigens have shown promise. The disease is notoriously difficult to treat. Eumycetoma may be unresponsive to standard antifungal therapy. Actinomycetoma responds to antibiotic therapy, but prolonged treatment is necessary. This review focuses on the etiopathogenesis, clinical features, laboratory diagnosis, and treatment of mycetoma.

Integrated Two-Analyte Population Pharmacokinetic Model for Antibody-Drug Conjugates in Patients: Implications for Reducing Pharmacokinetic Sampling

An integrated pharmacokinetics (PK) model that simultaneously describes concentrations of total antibody (Tab) and antibody‐conjugated monomethyl auristatin E (acMMAE) following administration of monomethyl auristatin E (MMAE)‐containing antibody–drug conjugates (ADCs) was developed based on phase I PK data with extensive sampling for two ADCs. Two linear two‐compartment models that shared all parameters were used to describe the PK of Tab and acMMAE, except that the deconjugation rate was an additional clearance pathway included in the acMMAE PK model compared to Tab. Further, the model demonstrated its ability to predict Tab concentrations and PK parameters based on observed acMMAE PK and various reduced or eliminated Tab PK sampling schemes of phase II data. Thus, this integrated model allows for the reduction of Tab PK sampling in late‐phase clinical development without compromising Tab PK characterization.

Sinonasal Mass-a Recent Study of Its Clinicopathological Profile

A variety of non-neoplastic and neoplastic conditions involving the nasal cavity, paranasal sinuses (PNS), and nasopharynx are commonly encountered in clinical practice. The objectives of the study were to identify various pathological conditions that present with sinus or nasal mass, to understand their varied clinical behavior, to know the distribution of various lesions among the different age and sex groups, and to study the management of sinonasal masses and its outcome on follow-up. A prospective study was carried out from September 2013 to August 2015, in the Otorhinolaryngology Department of Hi-Tech Medical College & Hospital, Bhubaneswar, Odisha. The study included patients of any age and sex presenting with nasal symptoms (suspected of a sinonasal mass). This study included all cases seen during the above duration. Complete history was taken and full clinical examination was carried out. Majority of the patients with sinonasal masses were in the age group 41-50 years. Male:female ratio was about 1.2:1. Nasal obstruction was the most common presentation. Most common non-neoplastic lesion was rhinosporidosis and most common benign lesion was hemangioma. Most common malignant lesion was maxillary carcinoma. The presenting features of all sinonasal lesions may be indistinguishable and pose diagnostic dilemma. Correlation of clinical, radiologic, and most importantly pathologic modalities is of utmost importance for accurate diagnosis.

A Comparative Effectiveness Research of Azathioprine and Cyclophosphamide on the Clinical and Serological Response in Pemphigus Vulgaris

CONTEXT

A prospective study was carried out to examine the efficacy of cyclophosphamide and azathioprine in pemphigus vulgaris.

AIMS

To compare the clinical and serological effect of azathioprine and cyclophosphamide in pemphigus patients.

MATERIALS AND METHODS

Prospective, institutional based study was conducted twenty-one patients of pemphigus vulgaris were initiated on either azathioprine (n = 9) or cyclophosphamide (n = 7) in addition to prednisolone and were evaluated clinically (mucosal and cutaneous severity) and serologically enzyme-linked immunosorbent assay (ELISA) at 0, 3 and 6 months.

RESULTS

Azathioprine had a slower onset of action with a statistically significant improvement seen by 6 months (P = 0.016). Cyclophosphamide had a faster onset of action (3 months) though there was no statistical difference in the efficacy between the two at the end of 6 months. The (RonT) was 33.3-44.4% for azathioprine and 28.8-42.9% for cyclophosphamide at 6 months. Though ELISA had a high sensitivity and specificity for diagnosis, as a tool for assessing therapeutic response a significant decrease was seen only till 3 months. This was restricted to Dsg1 for the azathioprine group and both Dsg3 and Dsg1 levels for the cyclophosphamide group. There were two deaths, both in the cyclophosphamide group.

CONCLUSIONS

Azathiorpine and cyclophosphamide are equally effective for mucosal and cutaneous disease in pemphigus after 6 months of therapy. Dsg ELISA is useful for diagnosis of pemphigus but is not a useful tool for monitoring response to therapy.