Exosomal microRNAs as potential biomarkers and therapeutic targets in corneal diseases

Exosomes are a subtype of extracellular vesicle (EV) that are released and found in almost all body fluids. Exosomes consist of and carry a variety of bioactive molecules, including genetic information in the form of microRNAs (miRNAs). miRNA, a type of small non-coding RNA, plays a key role in regulating genes by suppressing their translation. miRNAs are often disrupted in the pathophysiology of different conditions, including eye disease. The stability and easy detectability of exosomal miRNAs in body fluids make them promising biomarkers for the diagnosis of different diseases. Additionally, due to the natural delivery capabilities of exosomes, they can be modified to transport therapeutic miRNAs to specific recipient cells. Most exosome research has primarily focused on cancer, so there is limited research highlighting the importance of exosomes in ocular biology, particularly in cornea-associated pathologies. This review provides an overview of the existing evidence regarding the primary functions of exosomal miRNAs and their potential role in diagnostic and therapeutic applications in the human cornea.

MicroRNA and Protein Cargos of Human Limbal Epithelial Cell-Derived Exosomes and Their Regulatory Roles in Limbal Stromal Cells of Diabetic and Non-Diabetic Corneas

Epithelial and stromal/mesenchymal limbal stem cells contribute to corneal homeostasis and cell renewal. Extracellular vesicles (EVs), including exosomes (Exos), can be paracrine mediators of intercellular communication. Previously, we described cargos and regulatory roles of limbal stromal cell (LSC)-derived Exos in non-diabetic (N) and diabetic (DM) limbal epithelial cells (LECs). Presently, we quantify the miRNA and proteome profiles of human LEC-derived Exos and their regulatory roles in N- and DM-LSC. We revealed some miRNA and protein differences in DM vs. N-LEC-derived Exos' cargos, including proteins involved in Exo biogenesis and packaging that may affect Exo production and ultimately cellular crosstalk and corneal function. Treatment by N-Exos, but not by DM-Exos, enhanced wound healing in cultured N-LSCs and increased proliferation rates in N and DM LSCs vs. corresponding untreated (control) cells. N-Exos-treated LSCs reduced the keratocyte markers ALDH3A1 and lumican and increased the MSC markers CD73, CD90, and CD105 vs. control LSCs. These being opposite to the changes quantified in wounded LSCs. Overall, N-LEC Exos have a more pronounced effect on LSC wound healing, proliferation, and stem cell marker expression than DM-LEC Exos. This suggests that regulatory miRNA and protein cargo differences in DM- vs. N-LEC-derived Exos could contribute to the disease state.

Nasopharyngeal carriage of Streptococcus pneumoniae serotypes among sick and healthy children in northern India: A case-control study

BACKGROUND

Streptococcus pneumoniae is leading bacterial cause of community acquired pneumonia and according to World Health Organization, responsible for 14 % death in children. There is effective vaccine available against Streptococcus pneumoniae. Hence the primary objective was to isolate Streptococcus pneumoniae from nasopharyngeal swabs in children aged 2-59 months with and without community acquired pneumonia and to assess their serotypes.

METHODS

This case-control study was conducted in tertiary teaching institutes in northern India. Hospitalized children, aged 2-59 months, with World Health Organization-defined community acquired pneumonia were included as cases. Age matched healthy controls were recruited from immunization clinic. All enrolments were done after written informed parental consent. Nasopharyngeal swabs were taken from both cases and controls, and were cultured on 5 % sheep blood agar with gentamycin plate for growth of Streptococcus pneumoniae and incubated in a jar at 370 for 18-24 hrs. Quellung reaction test was used for serotyping.

RESULTS

From March 2017 to December 2022, 2693 children (1910 cases and 783 controls), were recruited. The median age of cases was 7 months and controls 10 months. Almost all the cases had received antibiotics prior to hospitalization. Streptococcus pneumoniae positivity in nasopharyngeal swab was 8.1 % in cases, of which 56.8 % were vaccine serotypes and 23.6 % in controls, of which 37.8 % were vaccine serotypes. Adjusted odds ratio of isolating vaccine serotypes among cases as compared to controls was 1.77 (95 % CI, 1.09-2.88).

CONCLUSION

Streptococcus pneumoniae isolation from nasopharyngeal was found to be in lower proportion in cases as compared to control, though colonization with vaccine serotypes was higher in cases as compared to control. Therefore, pneumococcal vaccine coverage must be increased to prevent community acquired pneumonia.

Survival Outcomes for Oligometastatic vs. Polymetastatic Extensive-Stage Small Cell Lung Cancer Following Consolidative Thoracic Radiotherapy

PURPOSE/OBJECTIVE(S)

For patients with limited metastatic burden, metastasis-directed radiotherapy has been shown to be associated with improved OS for certain types of cancer. However, these prior trials did not include patients with ES-SCLC. It is not yet clear if patients with oligometastatic ES-SCLC have improved outcomes over polymetastatic ES-SCLC after cTRT.

MATERIALS/METHODS

We identified patients treated with cTRT for ES-SCLC in 2013-2020 at a single institution. Oligometastatic disease was defined at the time of diagnosis as three or fewer organs with distant disease, and with each organ having three or fewer metastatic lesions. All other patients were considered polymetastatic. The Kaplan-Meier estimator, log-rank test, and multivariable Cox proportional hazards regression were used to compare OS, progression-free survival (PFS), local recurrence-free survival (LRFS), and new metastasis-free survival (NMFS) between oligometastatic and polymetastatic ES-SCLC patients undergoing cTRT.

RESULTS

Among 70 included patients, 36 were defined as oligometastatic. All patients received platinum-doublet chemotherapy and cT. Immunotherapy was given in 7 (19.4%) oligometastatic patients and 5 (14.7%) polymetastatic patients (p = 0.56). Median follow-up time was 38.2 months. Multivariable Cox regression analysis showed that oligometastatic disease (vs. polymetastatic disease) at diagnosis was associated with improved OS (hazard ratio [HR] 0.44, 95% CI 0.25-0.78, p = 0.005, 1-year OS 86.1% vs. 46.9%, 2-year OS 47.1% vs. 15.1%). PFS, LRFS, and NMFS were not significantly different between the cohorts. Among oligometastatic patients, pleural involvement (HR 2.44, 95% CI 1.02-5.83, p = 0.046) and lung involvement (HR 4.93, 95% CI 1.02-23.9, p = 0.047) were associated with inferior OS. Among the 26 of 36 (72.2%) oligometastatic patients with neither pleural nor bilateral lung involvement, 1-year OS was 88.5% and 2-year OS was 58.3%.

CONCLUSION

We observed that oligometastatic ES-SCLC patients treated with cTRT (especially those without pleural or bilateral lung involvement) have superior OS than those with polymetastatic disease. We encourage enrollment on the NRG LU007/RAPTOR randomized trial to determine the impact of complete or incomplete consolidative RT to up to 5 sites in ES-SCLC, especially in those with oligometastatic disease.

Abstract 514: Novel potent azetidine-based inhibitors bind irreversibly to Stat3 DNA-binding domain (DBD) and are efficacious against tumor growth in mice

Unlike classical Signal transducer and activator of transcription (Stat) signaling, which is transient in non-transformed cells, the aberrant activation of the family member, Stat3, occurs in malignant transformation and is implicated in breast, ovarian and many other human cancers. Thus, Stat3 remains a validated and important target for the discovery of novel anticancer drugs. Despite this, the discovery and development of potent Stat3 small molecule inhibitors has proven to be a significant challenge, and no drug is available yet in the market. We have discovered novel Stat3 irreversible azetidine inhibitors with unprecedent submicromolar potency through systematic medicinal chemistry structure activity relationship (SAR). Mechanism of action of most potent azetidine inhibitors depend on whether they are salicylic acids or not, i.e., salicylic acids preferably bind irreversibly to Stat3 Cys426 site in the DNA-binding domain (DBD), and non-salicylic acids, e.g., current lead H182, bind to Stat3 Cys468 DBD site. As expected, the inhibition of Stat3 DNA-binding activity was time dependent, with IC50 in the range of 0.27-0.87 µM at one hour incubation with active Stat3. On the other hand, azetidine salicylic acids also bind to the SH2 domain, although reversibly and at much weaker affinity, as determined in fluorescent polarization (FP) assay, with IC50 of 10-16 µM at one hour incubation, while non-salicylic acids, e.g., lead H182, present no binding affinity up to 600 µM for the SH2 domain. Despite that H182 does not bind to SH2 domain, it still inhibits its phosphorylation. Though lead compound H182 presents significant mouse in vivo efficacy, mouse in vivo pharmacokinetics shows very low plasma AUC, which correlates with quite high mouse in vitro hepatocyte CLint of 138 µL/min/106 cells; however, human in vitro hepatocyte assay gives much better results and is in the middle stability range (CLint of 14.6 µL/min/106 cells). The in vivo PK in other species, e.g., rat, is being determined. H182 represents a plausible molecule for further development.

Citation Format: Yue Chen, Ning Zhai, Yinsong Zhu, Peibin Yue, Nagendra Verma, Christine Brotherton-Pleiss, Wenzhen Fu, Kayo Nakamura, Weiliang Chen, Marcus Tius, Francisco J. Lopez-Tapia, James Turkson. Novel potent azetidine-based inhibitors bind irreversibly to Stat3 DNA-binding domain (DBD) and are efficacious against tumor growth in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 514.

Nasopharyngeal Carriage of Streptococcus pneumoniae Serotypes Among Healthy Children in Northern India

Streptococcus pneumoniae (SP) infections cause morbidity and mortality among children worldwide. Hence India introduced 13-valent pneumococcal conjugate vaccine (PCV-13) in 2017 in a phased manner. The primary objective of this study was to assess the proportion of healthy children having nasopharyngeal colonization (NP) with SP. Secondary objective was to determine prevalent serotype of SP among the PCV13 vaccinated and non-vaccinated children. This cross-sectional study was conducted in 4 hospitals of Lucknow District, Northern India. Three hundred healthy children (2-59 months) were recruited between July and August 2019 from vaccination-clinics of hospitals. NP specimen was cultured using 5% sheep blood agar plate containing gentamicin. Pneumococcal isolates were identified by optochin sensitivity and bile-solubility tests. Serotyping was done using Quellung Method. Of the 300 healthy children, 56.7% (170/300) were males and 59.3% (181/300) had received at least one dose of PCV13 vaccine. The NP carriage rate of SP among healthy children was 37.7% (113/300). Vaccine serotypes were found in 33.3% (22/66) in PCV vaccinated children and 48.9% (23/47) in non-vaccinated children (p 0.09). Common vaccine serotypes that isolated were: 18C, 19A, 19F, 23F, 3, 4, 6A, 6B, 9 V. Thus more than one-third of healthy children had NP colonization with SP. Adjusting for age, there was a trend for significant reduction in vaccine serotypes in the NP with one doses versus two or more doses (ptrend = 0.04).

Extra credit for disruption: trend of disruption in radiology academic journals

AIM

To identify the most disruptive publications, which are those that are cited more frequently than their own references, in academic radiology journals and their characteristics, such as the number of authors and relative time to publication.

MATERIAL AND METHODS

A comprehensive literature search was undertaken to identify the 100 most disruptive publications in the field of radiology. Subsequently, statistical analysis was applied to establish the distribution of disruptive scores of the isolated publications using a non-parametric probability density function. The relation between disruptive scores and citation counts was then determined, with the aid of a correlation coefficient. Finally, data regarding any significant connection between disruption scores and time of publication, number of authors, and study design were examined.

RESULTS

Analysing the top 100 papers in increments of 10-year periods showed no significant difference in the distribution of disruption scores over time. No correlation between an article's citation count and disruption score was established. Additionally, no significant relation between the number of authors/study design and disruption scores was identified.

CONCLUSION

The disruption score highlights significant impact elements not entirely accounted for by citation count. Its potential benefit in assessing scientific impact should be contemplated.

Abstract 5476: Novel azetidine-based STAT3 inhibitors induce misfolded protein response, endoplasmic reticulum stress and mitophagy, and inhibit breast tumor growth in vivo

Anticancer drugs that directly target Signal Transducer and Activator of Transcription (Stat)3 have remained elusive. We present azetidine-based small molecules as a new class of potent Stat3 inhibitors. Compounds H172 and H182 have potency (IC50) of 0.38-0.98 µM, H105 and H120 have IC50 of 1.75-2.07 µM against Stat3 DNA-binding activity in vitro, compared to the IC50 of >17 µM against Stat1 or Stat5 activity. Treatment of the triple-negative breast cancer (TNBC), MDA-MB-231 and MDA-MB-468 cells with the new compounds inhibited constitutive Stat3 activation, promoted Stat3 ubiquitination, blocked anchorage-dependent and independent growth, with potency, EC50 of 1.0-1.9 μM, and induced apoptosis of these cells. By contrast, pYStat1, pYStat5, pS727Stat3, pSrc, pJanus kinase, or the induction of other signaling events are not inhibited in compound-treated cells, and normal or tumor cells that do not harbor aberrantly-active Stat3 are only weakly inhibited. In vivo delivery of H120 or H182 as a single agent inhibited growth of human TNBC xenografts, and of H278 (HCl salt of H182) combined with radiation abrogated tumor growth and improved survival in mouse TNBC syngeneic models. These studies provide novel mechanism of disruption of aberrantly-active Stat3 and its dynamics in showing that the azetidine-based Stat3 inhibitors trigger Stat3 ubiquitination, and tumor cell death. H182 and H172 are new entities for further therapeutic development against TNBC and other cancers that harbor aberrantly-active Stat3.

Citation Format: Peibin Yue, Francisco Lopez-Tapia, Yinsong Zhu, Nagendra Verma, Felix Alonso-Valenteen, Simoun Mikhael, Lali Medina-Kauwe, Marcus Tius, James Turkson. Novel azetidine-based STAT3 inhibitors induce misfolded protein response, endoplasmic reticulum stress and mitophagy, and inhibit breast tumor growth in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5476.

Novel potent azetidine-based compounds irreversibly inhibit Stat3 activation and induce antitumor response against human breast tumor growth in vivo

Signal transducer and activator of transcription (Stat)3 is a valid anticancer therapeutic target. We have discovered a highly potent chemotype that amplifies the Stat3-inhibitory activity of lead compounds to levels previously unseen. The azetidine-based compounds, including H172 (9f) and H182, irreversibly bind to Stat3 and selectively inhibit Stat3 activity (IC₅₀ 0.38-0.98 μM) over Stat1 or Stat5 (IC₅₀ > 15.8 μM) in vitro. Mass spectrometry detected the Stat3 cysteine peptides covalently bound to the azetidine compounds, and the key residues, Cys426 and Cys468, essential for the high potency inhibition, were confirmed by site-directed mutagenesis. In triple-negative breast cancer (TNBC) models, treatment with the azetidine compounds inhibited constitutive and ligand-induced Stat3 signaling, and induced loss of viable cells and tumor cell death, compared to no effect on the induction of Janus kinase (JAK)2, Src, epidermal growth factor receptor (EGFR), and other proteins, or weak effects on cells that do not harbor aberrantly-active Stat3. H120 (8e) and H182 as a single agent inhibited growth of TNBC xenografts, and H278 (hydrochloric acid salt of H182) in combination with radiation completely blocked mouse TNBC growth and improved survival in syngeneic models. We identify potent azetidine-based, selective, irreversible Stat3 inhibitors that inhibit TNBC growth in vivo.

Estradiol inhibits HIV-1BaL infection and induces CFL1 expression in peripheral blood mononuclear cells and endocervical mucosa

An inhibitory effect of estradiol (E2) on HIV-1 infection was suggested by several reports. We previously identified increased gene expression of actin-binding protein cofilin 1 (CFL1) in endocervix in the E2-dominated proliferative phase of the menstrual cycle. Actin cytoskeleton has an integral role in establishing and spreading HIV-1 infection. Herein, we studied in vitro effects of E2 on HIV-1 infection and on CFL1 expression to gain insight into the mechanism of HIV-1 inhibition by E2. E2 dose-dependently inhibited HIV-1_BaL infection in peripheral blood mononuclear cells (PBMCs) and endocervix. In PBMCs and endocervix, E2 increased protein expression of total CFL1 and phosphorylated CFL1 (pCFL1) and pCFL1/CFL1 ratios. LIMKi3, a LIM kinase 1 and 2 inhibitor, abrogated the phenotype and restored infection in both PBMCs and endocervix; inhibited E2-induced expression of total CFL1, pCFL1; and decreased pCFL1/CFL1 ratios. Knockdown of CFL1 in PBMCs also abrogated the phenotype and partially restored infection. Additional analysis of soluble mediators revealed decreased concentrations of pro-inflammatory chemokines CXCL10 and CCL5 in infected tissues incubated with E2. Our results suggest a link between E2-mediated anti-HIV-1 activity and expression of CFL1 in PBMCs and endocervical mucosa. The data support exploration of cytoskeletal signaling pathway targets for the development of prevention strategies against HIV-1.

Effects of COVID-19 on maternal, child healthcare (MCH) services in slums: lessons from India

Background

The study aims to understand the effect of COVID lockdown on MCH for slum dwellers and coping mechanisms adopted in Indore and Agra, India. Slum women's perspectives on seeking, delaying, avoiding healthcare in COVID-19, barriers and facilitators were explored.

Methods

In-person qualitative interviews were conducted in slums in Sept-Oct 2020 with mothers who had deliveries; pregnant women needing ante-natal care; mothers with children <2 yrs needing immunization during COVID lockdown. 30 mothers requiring these MCH services during April -June 2020 (lockdown phase) were interviewed. We chose qualitative study over quantitative as a shorter and useful precedent to replicate in similar situations.

Results

Govt. and most private hospitals refused non-COVID services during lockdown.; Police restricted movement on roads. Being on COVID duty, frontline health functionaries were not doing outreach health sessions. Women missed ante-natal check-up, Iron Folate, Tetanus toxoid; Demand side challenges included fear of COVID infection, lack of money due to livelihood loss; Home deliveries by self, neighbors were resorted to; Maternal, neonatal deaths ensued; Children missed immunization e.g., Measles, DPT. Few peri-urban slum families visited nearby rural health facility for delivery. Some families borrowed money from community saving's groups for delivery in private hospitals. Few families visited low-cost private doctor/nurse for immunization of pregnant mother, children.

Conclusions

Demand and supply side factors led to pregnant women and children not receiving care during lockdown. Peri-urban slum families should be encouraged to link with nearby rural health facility for MCH services during COVID-19 or similar situations. Govt. partnering with private providers near slums will help access during challenging times. Promoting community savings groups as mandated under National Urban Health Mission can enable slum families borrow with ease when in need.

Key messages

Government health system should set up emergency (e.g., mobile clinic) MCH services for future epidemic, disaster, should partner with private doctors/nurses near slums.

Rural health infrastructure serving nearby peri-urban slums formally recognized by Govt. despite separate jurisdictions is an approach adaptable in LMIC cities.

Vegetable gardening in slum homes for food security especially in COVID-19 and well-being in India

Issue

With livelihood loss, uncertain earning, slum families are often food insecure, at risk of undernutrition particularly during COVID-19 in Indian and other LMIC cities. While wheat flour was provided free during lockdown, later at subsidized costs and during non-COVID times, vegetables need to be bought at market price.

Methods

UHRC provided seeds, encouraged families to grow vegetables in slums of Indore, India for five years. In 2019-20 and 20-21, data was gathered through interviews, observations in 20 slums (where &gt;15 families grew vegetables).

Results

Uptake of seeds increased from 900 families in 2019-20 to 1200 in 20-21. With sharing of surplus harvest, 70,000 persons benefited in 2020-21. Families overcame food insecurity by arranging just wheat flour and cooked a vegetable for a meal. Used paint tubs, broken buckets and small spaces were used. Creepers were made to climb on roofs, walls, trees. Green cover increased to &gt; 8 acres in 2021. The practice saves valuable family resources particularly in COVID-19 distress through provision of vegetables for family consumption.

Lessons

Perseverant efforts are key and help build a ‘fairer, healthier world'. Yield per family increased as they grow with incremental confidence. Despite small spaces slum families creatively grew vegetables. Children and youth help overcome constraints and are key actors. Early adopters serve as motivators and champions for subsequent adopters who begin growing vegetables on observing neighbours, friends grow vegetables and share with them. Nurturing plants, seeing vegetables grow fostered positivity, hope, motivation to grow every year, enhanced self-worth, and a positive feeling about their abode. People particularly children and youth learn how eating home-grown vegetables reduces carbon footprint of purchased vegetables transported to urban markets, save cost and overcome food insecurity. They reduce ambient air temperature to cool urban spaces.

Key messages

Despite small spaces, slum families grow, share vegetables, feel accomplished, enable food security, social cooperation, all crucial to well-being of slum populations. Methods used and lessons learnt of perseveringly motivating slum families have the potential of replication/adaptation in cities of India and other LMICs.

Birth Preparedness and Complication Readiness (BPACR) among brick kiln workers in Indore, India

Background

Birth preparedness and complication readiness (BPACR), promotes utilization of skilled maternal and neonatal care. Preparing for childbirth reduces delays in seeking care. Brick-kiln workers constitute a vulnerable social group who contribute to city infrastructure by laboring at low wages. 37% of the sample were Scheduled Castes, 49% Scheduled Tribes.

Methods

139 mothers of children &lt; 2 years, residing temporarily in brick kilns of Indore were asked about preparedness for birth of youngest child. Birth preparedness was assessed by enquiring about saving money, arranging transport, identifying health facility for delivery, identified family member to accompany for labor/emergency.

Findings

10% did &gt;3 BPACR practices implying good level of preparedness; 50% did 1-2 BPACR practices; 40% did no birth preparedness. Access to maternity benefit scheme was twice as likely to result in reasonable birth preparedness as compared to no access. Those with primary to class XII were twice as likely to practice birth preparedness as compared to those with no formal education. &gt;3 ANC was associated with 8 percentage points greater practice of reasonable BPACR as compared to &lt; 2 or no ANC. Mothers with knowledge of one danger sign each of pregnancy and delivery were 3 times more likely to practice BPACR than those without this knowledge. FGDs revealed challenges in access to bank account, obtaining required documents to apply for and access state maternity benefit. Lack of family support led to low BPCAR and low institutional delivery.

Conclusions

Brick-kiln women face risk of low utilization of government healthcare services. The health systems should conduct outreach antenatal care sessions in brick-kilns on knowledge of key danger signs and BPACR during health education and ANC counselling can help promote BPACR and hospital delivery. Information on requisite steps to apply for maternity benefit schemes should be shared among brick-kiln workers.

Key messages

It is crucial to promote BPACR among urban vulnerable sections, through NUHM’s outreach sessions by ANMs/ASHAs in brick-kiln, construction workers and similar groups. Access to maternity benefit cash transfer scheme should be enhanced particularly among excluded temporary urban groups such as brick-kiln workers as it is a motivation to avail hospital care.

Functional cooperation between ASK1 and p21Waf1/Cip1 in the balance of cell-cycle arrest, cell death and tumorigenesis of stressed keratinocytes

Both CDKN1A (p21 ^Waf1/Cip1) and Apoptosis signal-regulating kinase 1 (ASK1) play important roles in tumorigenesis. The role of p21 ^Waf1/Cip1 in attenuating ASK1-induced apoptosis by various stress conditions is well established. However, how ASK1 and p21 ^Waf1/Cip1 functionally interact during tumorigenesis is still unclear. To address this aspect, we crossed ASK1 knockout (ASK1KO) mice with p21 ^Waf1/Cip1 knockout (p21KO) mice to compare single and double-mutant mice. We observed that deletion of p21 ^Waf1/Cip1 leads to increased keratinocyte proliferation but also increased cell death. This is mechanistically linked to the ASK1 axis-induced apoptosis, including p38 and PARP. Indeed, deletion of ASK1 does not alter the proliferation but decreases the apoptosis of p21KO keratinocytes. To analyze as this interaction might affect skin carcinogenesis, we investigated the response of ASK1KO and p21KO mice to DMBA/TPA-induced tumorigenesis. Here we show that while endogenous ASK1 is dispensable for skin homeostasis, ASK1KO mice are resistant to DMBA/TPA-induced tumorigenesis. However, we found that epidermis lacking both p21 and ASK1 reacquires increased sensitivity to DMBA/TPA-induced tumorigenesis. We demonstrate that apoptosis and cell-cycle progression in p21KO keratinocytes are uncoupled in the absence of ASK1. These data support the model that a critical event ensuring the balance between cell death, cell-cycle arrest, and successful divisions in keratinocytes during stress conditions is the p21-dependent ASK1 inactivation.

Increased tracheostomy rates in head and neck cancer surgery during the COVID-19 pandemic

Surgical practice during the coronavirus disease 2019 (COVID-19) pandemic has changed significantly, without supporting data. With increasing experience, a dichotomy of practice is emerging, challenging existing consensus guidelines. One such practice is elective tracheostomy. Here, we share our initial experience of head and neck cancer surgery in a COVID-19 tertiary care centre, emphasizing the evolved protocol of perioperative care when compared to pre-COVID-19 times. This was a prospective study of 21 patients with head and neck cancers undergoing surgery during the COVID-19 pandemic, compared to 193 historical controls. Changes in anaesthesia, surgery, and operating room practices were evaluated. A strict protocol was followed. One patient tested positive for COVID-19 preoperatively. There was a significant increase in pre-induction tracheostomies (28.6% vs 6.7%, P = 0.005), median hospital stay (10 vs 7 days, P = 0.001), and postponements of surgery (57.1% vs 27.5%, P = 0.01), along with a significant decrease in flap reconstructions (33.3% vs 59.6%, P = 0.03). There was no mortality and no difference in postoperative morbidity. No healthcare personnel became symptomatic for COVID-19 during this period. Tracheostomy is safe during the COVID-19 pandemic and rates have increased. Despite increased rescheduling of surgeries and longer hospital stays, definitive cancer care surgery has not been deferred and maximum patient and healthcare worker safety has been ensured.

Emergence of spatio-temporal variations in chemotherapeutic drug efficacy: in-vitro and in-Silico 3D tumour spheroid studies

Background

The mechanisms of action and efficacy of cisplatin and paclitaxel at cell population level are well studied and documented, however the localized spatio-temporal effects of the drugs are less well understood. We explore the emergence of spatially preferential drug efficacy resulting from variations in mechanisms of cell-drug interactions.

Methods

3D spheroids of HeLa-C3 cells were treated with drugs, cisplatin and paclitaxel. This was followed by sectioning and staining of the spheroids to track the spatio-temporal apoptotic effects of the drugs. A mechanistic drug-cell interaction model was developed and simulated to analyse the localized efficacy of these drugs.

Results

The outcomes of drug actions on a local cell population was dependant on the interactions between cell repair probability, intracellular drug concentration and cell’s mitosis phase. In spheroids treated with cisplatin, drug induced apoptosis is found to be scattered throughout the volume of the spheroids. In contrast, effect of paclitaxel is found to be preferentially localized along the periphery of the spheroids. Combinatorial treatments of cisplatin and paclitaxel result in varying levels of cell apoptosis based on the scheduling strategy.

Conclusions

The preferential action of paclitaxel can be attributed to the cell characteristics of the peripheral population. The model simulations and experimental data show that treatments initiated with paclitaxel are more efficacious due to the cascading of spatial effects of the drugs.

Variability of contrast enhancement of pancreas on computed tomography in patients with acute pancreatitis and isolated extrapancreatic necrosis

BACKGROUND AND STUDY AIM

To evaluate the variability in the enhancement of pancreas on computed tomography (CT) in patients with acute pancreatitis (AP) and isolated extrapancreatic necrosis (EPN) and to investigate whether it affects the extrapancreatic findings and patient outcomes.

PATIENTS AND METHODS

This retrospective study comprised of consecutive patients with isolated EPN evaluated between April 2017 and April 2019. A radiologist measured the pancreatic attenuation values (PAV) of head, body, and tail on a contrast enhanced CT. Using a cut-off PAV of 100HU, patients were divided into two groups. The extrapancreatic CT findings and outcome parameters were compared between the two groups.

RESULTS

Thirty patients (mean age, 42.13 years, 17 males) with isolated EPN were evaluated. The mean PAV in the head, body, and tail was 83.13 HU (range, 59-161), 84.17 HU (range, 60-160), and 82.23 HU (range, 53-137). The overall mean PAV was 83.12 HU (range, 58-152). There were six patients with overall mean PAV≥100 HU. The group with PAV≥100 HU had a higher number of patients with infected necrosis (66.6% vs. 14.2%, P=0.018). PAV had a significant association with length of hospitalization (P=0.045).

CONCLUSION

There is significant variability in the pancreatic enhancement on CT among patients with AP and isolated EPN. Patients with PAV≥100 HU had a significantly longer hospital stay. This, however, may be related to a greater number of patients with infected necrosis in this group.

Local solutions by slum communities to deal with summer water scarcity: Learning from Indore, India

Issue

Government of India's, NITI Aayog reports that 600 million people in India face extreme water stress. Slums and similarly vulnerable urban populations face huge challenges in accessing water for basic needs, increasing in summers. Indore is an extreme water stressed city in India.

Methods

During Urban Health Resource Centre's (UHRC) program work in slums, including women's groups UHRC forms and trains in 2018 we learnt of acute water scarcity in summers. Women in 16 slums were motivated to evolve and implement possible solutions. Most slum dwellers provide services on low wages to the city. With public bore-wells drying-up, in Feb.- May 2019 UHRC helped women's groups' submit community requests, reminders to elected ward representatives and Municipal offices for free water tankers. UHRC motivated slum families to collectively negotiate with private providers to reduce cost, systematise water supply for more families. In 4 peri-urban slums we strengthened water access relationship between farmers and slum dwellers.

Results

During Feb.-May 2019 10 of the 16 slums received free water tankers from Municipal Corporation. More population of 4 peri-urban slums accessed water from farmer's tube-well. Slum families evolved coping mechanisms of storing more general use water in underground tanks or many cans. Families with larger storage shared water with needy families demonstrating social cooperation.

Lessons

Trained and mentored slum women's groups gently negotiating with elected ward-level politicians and municipal officials helps in provision of free water tankers in summers. This strategy to get govt. water supply in slums is adaptable in fast growing Indian cities. Owing to geographical proximity, rural-urban cooperation can help slums in city's fringes obtain water from farmer tube-wells used for irrigation. Fostering community cooperation helps more needy families get water.

Key messages

Slum communities develop local mechanisms to access and store water which need to be understood by civil society organisations and Government to improve solutions for water supply in summer months. Slum women emerge as dynamic actors to improve the lives of both women and men (Sen, 2000). In this case women help negotiate for and foster community cooperation for water, store more water.

Assessing and implementing practical ways to address slum health determinants: Learning from India

Issue

There is a need for adaptable/scalable methods to understand environmental determinants of health and well-being in slums of LMIC cities. Catalysing grassroots actions to reduce health inequalities is needed with strong community leadership in slums.

Methods

Conducted in 2016-2017 in Indore (3 m population), India this practice undertakes qualitative health assessments using simple, actionable indicators with community knowledge and prioritizes solutions. Participatory neighbourhood level assessment of sewerage, toilets, garbage disposal and water supply by slum women was done using three colour scale: red for poor condition, yellow for moderate condition and green for good condition across 24 slums. Since slum women live these challenges daily, they can assess conditions. A qualitative adaptation of WHO's Urban HEART, this practice seeks to learn how slum women assess conditions, implement actions for improvement of slum environment.

Results

Context responsive actions included submitting community petitions and reminders to Municipal authorities by slum women to repair sewerage lines, construct toilets, increase regularity of garbage collection and improve public water supply in slums. Of 24 slums assessed in 2016, 6 were designated as “red”, 14 as “yellow” and 4 as “green” on condition of toilets and sewerage. On garbage disposal and water supply, 8 slums were designated as “red”, 10 as “yellow” and 6 as “green”. With coordination with Municipal authorities in 2017, slums on “red” reduced to 3 in each group, those assessed as “green” increased to 10 with improved conditions.

Lessons

This approach helps slum communities to assess problems and implement solutions. The methodology is simple, low-cost, easily understood by less educated, academics, policy makers and uses community wisdom. It is adaptable for NGOs, relevant policies/guidelines in LMIC cities. This collective community health assessment directly catalyses demand side action.

Key messages

Collective efficacy is a group’s shared belief in its ability to utilize information, pursue actions to overcome obstacles accomplishing a valued goal. This method is key to replicate this practice. People’s efforts to bring public services to the slums through collective action can reduce urban health inequality.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

PLK1 targets NOTCH1 during DNA damage and mitotic progression

Notch signaling plays a complex role in carcinogenesis, and its signaling pathway has both tumor suppressor and oncogenic components. To identify regulators that might control this dual activity of NOTCH1, we screened a chemical library targeting kinases and identified Polo-like kinase 1 (PLK1) as one of the kinases involved in arsenite-induced NOTCH1 down-modulation. As PLK1 activity drives mitotic entry but also is inhibited after DNA damage, we investigated the PLK1-NOTCH1 interplay in the G2 phase of the cell cycle and in response to DNA damage. Here, we found that PLK1 regulates NOTCH1 expression at G2/M transition. However, when cells in G2 phase are challenged with DNA damage, PLK1 is inhibited to prevent entry into mitosis. Interestingly, we found that the interaction between NOTCH1 and PLK1 is functionally important during the DNA damage response, as we found that whereas PLK1 activity is inhibited, NOTCH1 expression is maintained during DNA damage response. During genotoxic stress, cellular transformation requires that promitotic activity must override DNA damage checkpoint signaling to drive proliferation. Interestingly, we found that arsenite-induced genotoxic stress causes a PLK1-dependent signaling response that antagonizes the involvement of NOTCH1 in the DNA damage checkpoint. Taken together, our data provide evidence that Notch signaling is altered but not abolished in SCC cells. Thus, it is also important to recognize that Notch plasticity might be modulated and could represent a key determinant to switch on/off either the oncogenic or tumor suppressor function of Notch signaling in a single type of tumor.

Inferior right hepatic vein on routine contrast-enhanced CT of the abdomen: prevalence and correlation with right hepatic vein size

AIM

To determine the prevalence of the inferior right hepatic vein (IRHV) in patients undergoing routine contrast-enhanced computed tomography (CECT) of the abdomen and to compare it with the size of the right hepatic vein (RHV).

MATERIALS AND METHODS

Two hundred and twenty-four consecutive patients who underwent routine CECT abdomen, with adequate venous opacification, were included in the study. The number and diameter of IRHVs and the diameter of the RHV was noted in each case.

RESULTS

A total of 214 IRHVs were detected in 126 cases (56.2%) with a mean diameter of 4.15±1.44 mm. The number of IRHVs ranged from one to four (more than one IRHV was present in 39.7% [50/126] of cases). In approximately one-third of cases (46/126), an IRHV ≥5 mm was found. A weak negative correlation was found between size of the RHV and IRHV (Pearson's correlation coefficient -0.222; p=0.01). The RHV was smaller in size in patients with an IRHV (7.34±1.88 mm) than in patients without an IRHV (8.47±1.99 mm) on CECT abdomen. A larger IRHV was associated with a smaller RHV (6.91±2.05 mm).

CONCLUSION

The presence of IRHV on routine CECT abdomen is frequent, and it is not uncommon to encounter more than one IRHV. The diameter of the IRHV has a weak negative correlation with the diameter of the RHV, and a smaller RHV is found in patients with an IRHV.

DNA Damage Stress: Cui Prodest?

DNA is an entity shielded by mechanisms that maintain genomic stability and are essential for living cells; however, DNA is constantly subject to assaults from the environment throughout the cellular life span, making the genome susceptible to mutation and irreparable damage. Cells are prepared to mend such events through cell death as an extrema ratio to solve those threats from a multicellular perspective. However, in cells under various stress conditions, checkpoint mechanisms are activated to allow cells to have enough time to repair the damaged DNA. In yeast, entry into the cell cycle when damage is not completely repaired represents an adaptive mechanism to cope with stressful conditions. In multicellular organisms, entry into cell cycle with damaged DNA is strictly forbidden. However, in cancer development, individual cells undergo checkpoint adaptation, in which most cells die, but some survive acquiring advantageous mutations and selfishly evolve a conflictual behavior. In this review, we focus on how, in cancer development, cells rely on checkpoint adaptation to escape DNA stress and ultimately to cell death.

Correlation of Foot Bimalleolar Angle and Ultrasonography in Assessing the Severity of Club Foot in Neonates Treated by the Ponseti Method

Introduction: Correlation of Pirani score and foot bimalleolar (FBM) angle has been used in few studies but correlation of FBM angle with ultrasonography has never been evaluated so they are being correlated in assessing the severity of clubfoot in neonates treated by Ponseti method. Material and Methods: Thirty-two feet with congenital talipes equinovarus (CTEV) deformity in neonates were prospectively treated by the Ponseti method. FBM angle and ultrasound parameters were measured three times i.e. at the time of initial presentation, at four weeks of treatment and at completion of treatment. The feet were divided according to the Pirani score in groups: one (0-2.0), two (2.5-4) and three (4.5-6). Correlation between FBM angle and ultrasound parameters were evaluated using Pearson correlation/regression. Results: Correlation between FBM angle and ultrasound parameters were statistically significant (p-value < 0.05). Conclusion: Ultrasound has the potential to accurately depict the pathoanatomy in clubfoot. FBM angle and ultrasound are objective methods to assess the severity of clubfoot. FBM angle and ultrasonography correlated in severity of deformity and correction achieved along the course of treatment.

Immune deficiency and autoimmunity in patients with CTLA-4 (CD152) mutations

Immune deficiency disorders are a heterogeneous group of diseases of variable genetic aetiology. While the hallmark of immunodeficiency is susceptibility to infection, it is increasingly clear that autoimmunity is prevalent, suggestive of a more general immune dysregulation in some cases. With the increasing use of genetic technologies, the underlying causes of immune dysregulation are beginning to emerge. Here we provide a review of the heterozygous mutations found in the immune checkpoint protein CTLA-4, identified in cases of common variable immunodeficiency disorders (CVID) with accompanying autoimmunity. Study of these mutations provides insights into the biology of CTLA-4 as well as suggesting approaches for rational treatment of these patients.