ZEB1 loss increases glioma stem cell tumorigenicity and resistance to chemoradiation

OBJECTIVE

Glioblastoma has been known to be resistant to chemotherapy and radiation, whereas the underlying mechanisms of resistance have not been fully elucidated. The authors studied the role of the transcription factor ZEB1 (zinc finger E-box-binding homeobox 1 protein), which is associated with epithelial-mesenchymal transition (EMT) and is central to the stemness of glioblastoma, to determine its role in therapeutic resistance to radiation and chemotherapy. The authors previously demonstrated that ZEB1 is deleted in a majority of glioblastomas.

METHODS

The authors explored resistance to therapy in the context of ZEB1 loss and overexpression in glioma stem cells (GSCs) and in patient data.

RESULTS

Patients with ZEB1 loss had a shorter survival time than patients with wild-type ZEB1 in both the high- and low-MGMT groups. Consistent with the clinical data, mice implanted with ZEB1 knockdown GSCs showed shortened survival compared with mice inoculated with nonsilencing control (NS) short-hairpin RNA (shRNA) GSC glioblastoma. ZEB1-deleted GSCs demonstrated increased tumorigenicity with regard to proliferation and invasion. Importantly, GSCs that lose ZEB1 expression develop enhanced resistance to chemotherapy, radiotherapy, and combined chemoradiation. ZEB1 loss may lead to increased HER3 expression through the HER3/Akt pathway associated with this chemoresistance. Conversely, overexpression of ZEB1 in GSCs that are ZEB1 null leads to increased sensitivity to chemoradiation.

CONCLUSIONS

The study results indicate that ZEB1 loss in cancer stem cells confers resistance to chemoradiation and uncovers a potentially targetable cell surface receptor in these resistant cells.

Xpert Ultra in diagnosing extrapulmonary TB: accuracy and trace calls

INTRODUCTION: Xpert Ultra (Ultra) was developed to improve the detection of TB; however, data on Ultra´s diagnostic accuracy in extrapulmonary TB (EPTB) are limited.METHODS: In this prospective diagnostic accuracy study, 242 EPTB samples were subjected to Ultra and Xpert MTB/Rif (Xpert) testing, and these were compared with both culture and a composite gold standard.RESULTS: Compared to culture, Ultra sensitivity and specificity using bone, cerebrospinal fluid (CSF), lymph node and tissue samples, and overall were respectively 100% and 77.3%, 75% and 100%, 87.5% and 87.5%, 100% and 87%, and 89.7% and 87.4%; in comparison to the composite gold standard, Ultra´s sensitivity and specificity were respectively 66.7% and 100%, 17.6% and 100%, 46.9% and 95.7%, 38.5% and 94.1%, and 46.2% and 96.9%. Using latent class analysis, sensitivity and specificity were respectively 94.5% and 96.3% for Ultra, 65.5% and 99.8% for Xpert, and 58.6% and 99.2% for culture. There were 22/242 (9%) trace calls on Ultra.CONCLUSION: We found improved sensitivity for Ultra compared to Xpert, although Ultra specificity was lower, with a large number of trace results (9%).

Elevated Asparagine Biosynthesis Drives Brain Tumor Stem Cell Metabolic Plasticity and Resistance to Oxidative Stress

Asparagine synthetase (ASNS) is a gene on the long arm of chromosome 7 that is copy-number amplified in the majority of glioblastomas. ASNS copy-number amplification is associated with a significantly decreased survival. Using patient-derived glioma stem cells (GSC), we showed that significant metabolic alterations occur in gliomas when perturbing the expression of ASNS, which is not merely restricted to amino acid homeostasis. ASNS-high GSCs maintained a slower basal metabolic profile yet readily shifted to a greatly increased capacity for glycolysis and oxidative phosphorylation when needed. This led ASNS-high cells to a greater ability to proliferate and spread into brain tissue. Finally, we demonstrate that these changes confer resistance to cellular stress, notably oxidative stress, through adaptive redox homeostasis that led to radiotherapy resistance. Furthermore, ASNS overexpression led to modifications of the one-carbon metabolism to promote a more antioxidant tumor environment revealing a metabolic vulnerability that may be therapeutically exploited. IMPLICATIONS: This study reveals a new role for ASNS in metabolic control and redox homeostasis in glioma stem cells and proposes a new treatment strategy that attempts to exploit one vulnerable metabolic node within the larger multilayered tumor network.

Nano-formulation of herbo-mineral alternative medicine from linga chenduram and evaluation of antiviral efficacy

Traditional medicine is becoming a primary source of health care in many countries in recent years. The current study proposes a new dimension of understanding a traditional origin treatment, using herbo-mineral preparations in nanoform. The herbo-mineral preparation, Linga chenduram [HMLC], was prepared according to the ancient palm script protocol dates back to 1000 years. In search of alternative therapy for the coronavirus, an attempt was made to determine this ethnic medicine formulation's therapeutic potential for viral hepatitis infection. The Hepatitis C virus [HCV] has several genomic similarities with SARS-CoV-2 viruses. The herbo-mineral formulation (HMLC) were analyzed using UV–vis, EDAX, FTIR, XRD, SEM, and TEM studies. SEM images confirmed the ' presence of nanoparticles with agglomerated conditions having an average grain size of 18 to 25 nm. EDAX studies showed the presence of metallic components in oxide or sulfide form in HMLC. The HCV inhibitory effects of HMLC indicated a good response. The cytotoxicity of this preparation against the Huh-7 human hepatoma cell line was significant. The HMLC showed a strong inhibitory effect on HCV replication in a dose-dependent manner. The genomic component of HCV is similar to COVID −19 virus. The Hepatitis C virus (HCV) NS3/4A protease has a striking three-dimensional structural similarity to the SARS-CoV2 M^pro protease, particularly in the arrangement of key active site residues. So HMLC can be tried to treat coronavirus infection. At higher concentrations, HMLC exhibited over 100-fold inhibition. In the MTT assay, HMLC did not show any apparent cytotoxic effect on cell viability at the concentrations 1–100 µg. Histological studies indicated that the liver and kidney did not experience any toxicity by 7 and 15 consecutive days of administration of HMLC on experimental Wistar rats. Hence, the HMLC can be tried as a therapy for COVID −19 infections using the preparations strictly according to ethnopharmacological protocol and optimum doses.

A multicentre observational study on the epidemiology, risk factors, management and outcomes of mucormycosis in India

OBJECTIVES

To describe the epidemiology, management and outcome of individuals with mucormycosis; and to evaluate the risk factors associated with mortality.

METHODS

We conducted a prospective observational study involving consecutive individuals with proven mucormycosis across 12 centres from India. The demographic profile, microbiology, predisposing factors, management and 90-day mortality were recorded; risk factors for mortality were analysed.

RESULTS

We included 465 patients. Rhino-orbital mucormycosis was the most common (315/465, 67.7%) presentation followed by pulmonary (62/465, 13.3%), cutaneous (49/465, 10.5%), and others. The predisposing factors included diabetes mellitus (342/465, 73.5%), malignancy (42/465, 9.0%), transplant (36/465, 7.7%), and others. Rhizopus species (231/290, 79.7%) were the most common followed by Apophysomyces variabilis (23/290, 7.9%), and several rare Mucorales. Surgical treatment was performed in 62.2% (289/465) of the participants. Amphotericin B was the primary therapy in 81.9% (381/465), and posaconazole was used as combination therapy in 53 (11.4%) individuals. Antifungal therapy was inappropriate in 7.6% (30/394) of the individuals. The 90-day mortality rate was 52% (242/465). On multivariate analysis, disseminated and rhino-orbital (with cerebral extension) mucormycosis, shorter duration of symptoms, shorter duration of antifungal therapy, and treatment with amphotericin B deoxycholate (versus liposomal) were independent risk factors of mortality. A combined medical and surgical management was associated with a better survival.

CONCLUSIONS

Diabetes mellitus was the dominant predisposing factor in all forms of mucormycosis. Combined surgical and medical management was associated with better outcomes. Several gaps surfaced in the management of mucormycosis. The rarer Mucorales identified in the study warrant further evaluation.

Biomedical waste management: study on the awareness and practice among healthcare workers in a tertiary teaching hospital

Bio-medical waste has a higher potential of infection and injury to the healthcare worker, patient and the surrounding community. Awareness programmes on their proper handling and management to healthcare workers can prevent the spread of infectious diseases and epidemics. This study was conducted in a tertiary care hospital to assess the impact of training, audits and education/implementations from 2009 to 2012 on awareness and practice of biomedical waste segregation. Our study reveals focused training, strict supervision, daily surveillance, audits inspections, involvement of hospital administrators and regular appraisals are essential to optimise the segregation of biomedical waste.

Use of CHROMagar medium in the differentiation ofCandidaspecies: is it cost-effective in developing countries?

The opportunistic infection of humans with Candida is becoming more common. As several species of Candida are relatively insusceptible to the commonly used antifungal drugs, rapid identification of the species involved can facilitate effective treatment. CHROMagar Candida medium (CCM) is a commercial product designed to allow the rapid identification of Candida to species level. To explore the potential usefulness of CCM in a developing country, attempts were made to identify the Candida species in 107 Indian isolates (obtained, consecutively, from 90 clinical specimens, over a year-long period, in a tertiary-level teaching hospital), using CCM and more conventional methods in parallel. The most common species appeared to be C. tropicalis (representing 40% of the isolates), followed by C. albicans (28%) and C. glabrata (23%). Although use of CCM allowed the isolates from 84 (93.3%) of the clinical specimens to identified to species level within 48 h, it took at least 7 days to identify the yeasts in 90% of the specimens using the more conventional procedures. With the results of the conventional methods set as the 'gold standard', the use of CCM appeared to allow all of the C. albicans, C. tropicalis and C. krusei isolates and most (92%) of the C. glabrata to be correctly identified. The costs/isolate identified with the CCM were no more than those of the conventional methods. As many (67%) of the isolates examined were of potentially drug-resistant yeasts (C. tropicalis, C. glabrata or C. krusei), there is clearly a need to identify local isolates quickly, to prevent treatment with ineffective drugs. In terms of both performance and cost, CCM appears to be a good method to use.

Tuberculosis in a renal allograft recipient presenting with intussusception

Extra-pulmonary tuberculosis (TB) is more common in renal allograft recipients and may present with dissemination or an atypical features. We report a renal allograft recipient with intestinal TB presenting 3 years after transplantation with persistent fever, weight loss, diarrhea, abdominal pain and mass in the abdomen with intestinal obstruction. He was diagnosed to be having an ileocolic intussusception which on resection showed a granulomatous inflammation with presence of acid-fast bacilli (AFB) typical of Mycobacterium tuberculosis. In addition, AFB was detected in the tracheal aspirate, indicating dissemination. He received anti-TB therapy (ATT) from the fourth postoperative day. However, he developed a probable immune reconstitution inflammatory syndrome (IRIS) with multiorgan failure and died on 11(th) postoperative day. This is the first report of intestinal TB presenting as intussusception in a renal allograft recipient. The development of IRIS after starting ATT is rare in renal allograft recipients. This report highlights the need for a high index of suspicion for diagnosing TB early among renal transplant recipients and the therapeutic dilemma with overwhelming infection and development of IRIS upon reduction of immunosuppression and starting ATT.

Agreement between skin testing and QuantiFERON-TB Gold In-Tube assay (QFT-TB) in detecting latent tuberculosis infection among household contacts in India

AIMS

The present study was designed to find the agreement between Tuberculin Skin Test and interferon gamma assay test in detecting latent tuberculosis infection in household contacts of sputum culture positive tuberculosis cases.

SETTING

Department of Community Medicine, Christian Medical College, Vellore.

METHODS

One hundred and fifty household contacts of sputum culture positive tuberculosis cases were tested with both the methods simultaneously and actual as well as kappa agreement was determined.

RESULTS

The overall actual agreement between both the tests was found to be 82% with a kappa agreement of 0.57.

CONCLUSION

The agreement was very high (both percentage agreement and Kappa) in pediatric contacts but it was poor in adult contacts.

Evaluation of the microscopic observational drug susceptibility assay for rapid and efficient diagnosis of multi-drug resistant tuberculosis

PURPOSE

Tuberculosis (TB) is endemic in India and the burden of multi-drug-resistant tuberculosis (MDR-TB) is high. Early detection of MDR-TB is of primary importance in controlling the spread of TB. The microscopic observational drug susceptibility (MODS) assay has been described as a cost-effective and rapid method by which mycobacterial culture and the drug susceptibility test (DST) can be done at the same time.

MATERIALS AND METHODS

A total of 302 consecutive sputum samples that were received in an accredited mycobacteriology laboratory for conventional culture and DST were evaluated by the MODS assay.

RESULTS

In comparison with conventional culture on Lowenstein Jensen (LJ) media, the MODS assay showed a sensitivity of 94.12% and a specificity of 89.39% and its concordance with the DST by the proportion method on LJ media to isoniazid and rifampicin was 90.8% and 91.5%, respectively. The turnaround time for results by MODS was 9 days compared to 21 days by culture on LJ media and an additional 42 days for DST by the 1% proportion method. The cost of performing a single MODS assay was Rs. 250/-, compared to Rs. 950/- for culture and 1st line DST on LJ.

CONCLUSION

MODS was found to be a sensitive and rapid alternative method for performing culture and DST to identify MDR-TB in resource poor settings.

Does solid culture for tuberculosis influence clinical decision making in India?

SETTING

Medical units at an academic tertiary referral hospital in Southern India.

OBJECTIVE

To investigate the impact of solid culture on Löwenstein-Jensen medium on clinical decision making.

DESIGN

In a retrospective review of 150 culture-positive and 150 culture-negative consecutively sampled tuberculosis (TB) suspects, treatment decisions were analysed at presentation, after the availability of culture detection results and after the availability of drug susceptibility testing (DST) culture results.

RESULTS

A total of 124 (82.7%) culture-positive patients and 35 (23.3%) culture-negative patients started anti-tuberculosis treatment prior to receiving their culture results; 101 patients (33.7%) returned for their results; two (1.3%) initiated treatment based on positive culture and no culture-negative patients discontinued treatment. DST was performed on 119 (79.3%) positive cultures: 30 (25.2%) showed any resistance, eight (6.7%) showed multidrug resistance and one (0.84%) showed extensively drug-resistant TB. Twenty-eight patients (23.5%) returned for their DST results. Based on DST, treatment was modified in four patients (3.4%).

CONCLUSION

Using solid culture, 150 cultures need to be tested for one treatment modification and 30 for DST. The cost of the widespread application of culture will need to be balanced against its impact on treatment decisions in India.

Diagnostic accuracy of the microscopic observation drug susceptibility assay: a pilot study from India

SETTING

The microscopic observation drug susceptibility (MODS) assay is a rapid, sensitive, low-cost liquid culture technique.

OBJECTIVE

To establish the accuracy of MODS for the detection of active pulmonary tuberculosis (TB), and to document the costs and challenges of setting up this assay in a low-income setting.

DESIGN

Prospective blinded pilot study of 200 adult TB suspects at a tertiary referral hospital in India. Reference standard included culture (Löwenstein-Jensen and automated liquid culture) and clinical diagnosis.

RESULTS

Patients were mostly male (n = 122, 61.1%) and out-patients (n = 184, 92.0%), with a mean age of 40.4 years (standard deviation 16.2). Seventeen (8.5%) were human immunodeficiency virus infected and 47 (23.5%) were reference culture-positive. Compared to reference culture, MODS was 78.9% sensitive (95%CI 62.2-90.0) and 96.7% specific (95%CI 92.0-98.8). Clinical assessment suggested that MODS was false-negative in 3/8 reference culture-positive MODS-negatives and true-positive in 4/6 reference culture-negative MODS-positives. MODS was faster than solid (P < 0.001) and liquid culture (P = 0.088), and cheaper than both.

CONCLUSION

MODS may be a good alternative to automated liquid culture, but there were several challenges in setting up the assay. Prior training and validation, setup costs and inability to rule out cross-contamination need to be taken into account before the test can be established.

Blinded evaluation of commercial urinary lipoarabinomannan for active tuberculosis: a pilot study

SETTING

Urine antigen testing is an attractive strategy for the diagnosis of active tuberculosis (TB), but accuracy data are scarce.

OBJECTIVE

To prospectively evaluate the diagnostic performance of commercial urinary lipoarabinomannan (LAM) antigen testing for active TB among pulmonary and extra-pulmonary TB suspects.

DESIGN

Prospective blinded evaluation of 200 adult TB suspects at a tertiary referral hospital in India. Reference standards included culture and clinical diagnosis.

RESULTS

Patients were 61% male (mean age 40.4 years): 8.5% were human immunodeficiency virus (HIV) infected and 47 of 200 (23.5%) were culture-positive for TB. Compared to positivity on either Löwenstein-Jensen (LJ) or BACTEC cultures, LAM sensitivity was 17.8% (95%CI 8.5-32.6), while specificity was 87.7% (95%CI 81.3-92.3). Compared to positivity on both LJ and BACTEC, LAM sensitivity was 5.8% (95%CI 12.5-44.9), with a specificity of 88.8% (95%CI 82.7-92.9). Compared to the clinical diagnosis, LAM sensitivity was 20.0% (95%CI 1.1-70.1), with a specificity of 83.3% (95%CI 50.9-97.0). HIV and smear status did not influence test accuracy.

CONCLUSION

In its current form, LAM is insensitive for the diagnosis of active TB, although its specificity is adequate.

Unusual presentation of entomophthoromycosis

Rhinoentomophthoromycosis caused by Conidiobolus sp commonly presents as a chronic granulomatous lesion that affects the rhinofacial subcutaneous tissue. We present an 18-year-old girl who presented with progressive bilateral proptosis and loss of vision since 2 weeks. Biopsy and fungal cultures confirmed diagnosis of Conidiobolus sp infection of the paranasal sinuses bilaterally with orbital extension and blindness. The clinical picture was complicated by the presence of sputum-positive cavitatory pulmonary tuberculosis, which was diagnosed at the same time. To our knowledge, this is the first such case to be reported from India. We also discuss the management of entomophthoromycosis. Despite many reports of success, there remains no consensus on the treatment of Conidiobolus infections of the nose and the paranasal sinuses with antifungal agents.

Varied clinical manifestations of Penicillium marneffei in patients with human immunodeficiency virus: a report from south India

Penicillium marneffei is a dimorphic fungus endemic to northeast India. This is the first report of penicilliosis from a hospital in south India. Three patients with diverse clinical manifestations who presented to a tertiary care hospital are described. High index of clinical suspicion and knowledge of 'local' microbiology is paramount in early diagnosis and timely treatment.

A pilot study of seroprevalence of influenza virus type A in Vellore, south India

BACKGROUND & OBJECTIVES

Influenza virus type A is active in many regions of the world. However, information from many parts of India is sparse. Hence we carried out a serological study on the prevalence of antibodies to influenza virus type A in Vellore, south India.

METHODS

Antibodies to influenza virus type A (H1N1 and H3N2) were detected using a haemagglutination inhibition (HI) test. A total of 186 individuals comprising healthy blood donors and laboratory workers were tested.

RESULTS

The titres ranged from < 20-2580, with a high geometric mean titre (GMT) of 200 for H3N2 and < 20-1280 with a GMT of 74 for H1N1 serotype of influenza virus type A. Among the 186 serum samples tested, 175 (94.04%) were positive for H1N1 and 185 (99.5%) for H3N2 with a titre > 20.

INTERPRETATION & CONCLUSION

The prevalence of elevated level of antibodies in the individuals indicates a high exposure to the influenza A virus in our population with a seropositive status in 99.5 per cent of the individuals tested. Virus surveillance needs to be instituted in different parts of the country to monitor the activity of these viruses.

"Permanent" records: experience with data migration in radiology information system and picture archiving and communication system replacement

In the replacement of both a radiology information system (RIS) and a picture archiving and communication system (PACS) archive, data were migrated from the prior system to the new system. We report on the process, the time and resources required, and the fidelity of data transfer. We find that for two PACS archives, both organized according to the Digital Imaging and Communications in Medicine (DICOM) information model, data may be transferred with full fidelity, but the time required for transfer is significant. Transfer from off-line backup media was found to be faster than transfer from our robotic tape library. In contrast, the RIS replacement required extensive labor to translate prior data between dissimilar information models, and some data were inevitably lost in the translation. Standards for RIS information models are needed to promote the migration of data without loss of content.