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Simple Summary: The migration strategies, movement patterns, and habitat associations of long-distance migratory raptors remain largely unknown. We deployed PTT-GSM satellite transmitters on five raptor species, four of which are threatened, with the objective of investigating their daily and seasonal movement patterns, migration flyways, home-range patterns, and habitat associations in their wintering areas. This study shows that raptors wintering in Western India undertake annual migration across the Western Circum–Himalayan Corridor of the Central Asian Flyway (CAF) to circumvent some of the highest mountain ranges in the world. Single individuals of the Greater Spotted Eagle (Clanga clanga), Indian Spotted Eagle (Clanga hastata), Tawny Eagle (Aquila rapax), Western Marsh Harrier (Circus aeruginosus), and two Pallid Harriers (Circus macrourus) were deployed with satellite transmitters in 2021 to study their home ranges, habitat associations, movement, and migration patterns. Data were collected for a combined number of 2291 days, providing 84,544 locations. Home ranges were calculated as kernel utilization distributions and expressed as 95% KDE and core areas as 50% KDE. Overall, eagles had larger home ranges (mean ± SD) of 942.70 ± 937.83 km2 compared to harriers, 43.84 ± 35.55 km2. Among eagles, the Greater Spotted Eagle had the largest home-range size of 2147.03 km2 calculated in Kazakhstan, while the female Pallid Harrier had the smallest home range of 5.74 km2 in Russia. Daily and monthly distances varied among eagles and harriers. The female Pallid Harrier covered the longest average monthly distance of 8585.43 ± 11,943.39 km, while the shortest monthly distance of 1338.22 ± 716.38 km was traveled by the Indian Spotted Eagle. All tagged birds migrated toward higher latitudes in the Northern hemisphere, except the Indian Spotted Eagle, which migrated to Pakistan. The male Western Marsh Harrier covered the longest migration distance in a shorter span of time, while the female Pallid Harrier took the longest to cover its migration distance. Overall, the daily distance covered during migration varied from 115.09 km traveled by the Indian Spotted Eagle to an overwhelming distance of 2035.85 km covered by the male Western Marsh Harrier. Scrubs, water bodies, croplands, and settlements were important habitat features associated with eagles, while croplands, open scrub, and built-up areas were associated with the female Pallid Harrier. The male Western Marsh Harrier was found to be primarily associated with saltpans and salt-affected areas having emergent vegetation. This study presents new insights into the movement and spatial ecology of long-distance migrant raptors that winter in Western India. We provide preliminary support for the use of the Western Circum–Himalayan Corridor as one of the important corridors of the Central Asian Flyway that warrants much appreciation among the current set of flyway corridors. [ABSTRACT FROM AUTHOR]

The cancer treatment landscape is significantly evolving, focusing on advanced radiation therapy methods to maximize effectiveness and minimize the adverse effects. Recognized as a pivotal component in cancer and disease treatment, radiation therapy (RT) has drawn attention in recent research that delves into its intricate interplay with inflammation and the immune response. This exploration unveils the underlying processes that significantly influence treatment outcomes. In this context, the potential advantages of combining bronchoscopy with RT across diverse clinical scenarios, alongside the targeted impact of brachytherapy, are explored. Concurrently, radiation treatments serve multifaceted roles such as DNA repair, cell elimination, and generating immune stress signaling molecules known as damage‐associated molecular patterns, elucidating their effectiveness in treating various diseases. External beam RT introduces versatility by utilizing particles such as photons, electrons, protons, or carbon ions, each offering distinct advantages. Advanced RT techniques contribute to the evolving landscape, with emerging technologies like FLASH, spatially fractionated RT, and others poised to revolutionize the field. The comprehension of RT, striving for improved treatment outcomes, reduced side effects, and facilitating personalized and innovative treatments for cancer and noncancer patients. After navigating these advancements, the goal is fixed to usher in a new era in which RT is a cornerstone of precision and effectiveness in medical interventions. In summarizing the myriad findings, the review underscores the significance of understanding the differential impacts of radiation approaches on inflammation and immune modulation, offering valuable insights for developing innovative therapeutic interventions that harness the immune system in conjunction with RT. Significance Statements: This extensive review offers a comprehensive analysis of conventional radiotherapy and the latest advancements, such as FLASH and spatially fractionated radiation therapy, with the goal of reducing treatment‐related complications. The main goal is to reduce any negative impacts associated with treatment, prioritizing the well‐being of the patient. The article acknowledges the constraints of current radiotherapy methods and emphasizes the need for further research to enhance the effectiveness of cancer treatment. In addition, the manuscript highlights the promising prospects of upcoming advancements in cancer treatment. It delves into the realm of molecular targeted therapies and immunotherapy, examining the potential synergies between the two. This review methodically examines important aspects of advancing cancer treatment strategies and addressing significant challenges within radiation therapy. [ABSTRACT FROM AUTHOR]

The Barda Wildlife Sanctuary (Barda WLS) is a semi-arid ecosystem that plays an important role in the conservation of mammalian carnivores. It is essential to evaluate the population of important wild prey species in Barda, which has conservation implications for mammalian predators and themselves. We assessed the density, biomass, and population structure of wild prey species by surveying road (n = 10) and trail (n = 8) transects using the distance sampling framework method. We used male-to-female sex ratios and the percent contribution of each age class to assess population structure. Mean group size (MGS), median group size (Mdgs), and mean crowding (Mc) were calculated to analyze group size. Of the species studied, Indian peafowl had the highest density (51.61 ± 7.08 individuals/km2), followed by wild pig (10.77 ± 4.59), blue bull (3.50 ± 0.51), Indian hare (3.03 ± 0.73), and spotted deer (0.62 ± 0.04). The male-to-adult female sex ratio was biased towards females, except for Indian peafowl. All species had small group sizes except wild pigs. The results of this study can aid in its development as one of the important protected areas in Gujarat for the conservation of mammalian predators, along with framing conservation strategies for Barda WLS. [ABSTRACT FROM AUTHOR]

Understanding the spatial ecology of translocated leopards (Panthera pardus fusca) is crucial for their conservation and the effective assessment of conflict management strategies. We investigated the home range and habitat preferences of five radio-collared leopards (n = 5; 2 males; 3 females) in the Gir landscape. Additionally, we examined the usefulness of the capture-release strategy for these animals. We assessed home range and habitat selection using kernel density estimation (at 95% and 50% levels) and compositional analysis. Our findings revealed that leopards exhibited distinct patterns of movement, often returning to their original capture site or nearby locations or exploring new areas within 3 to 25 days, covering distances ranging from 48 to 260 km. The average home range (95% FK) was estimated at 103.96±36.37 (SE) km2, with a core area usage (50% FK) of 21.38±5.95 km2. Seasonally, we observed the largest home ranges during summer and the smallest during winter. Males exhibited larger home ranges (95% FK, 151±64.28 km2) compared to females (56.18±14.22 km2). The habitat analysis indicated that agricultural areas were consistently preferred in the multi-use landscape at the 2nd order habitat selection level. Additionally, habitat around water bodies was highly favoured at the 3rd order, with distinct variations in habitat selection observed during day and night. This study highlights the significance of riverine and scrubland habitats, as leopards exhibited strong preferences for these habitats within their home ranges. We emphasize the importance of conserving natural habitat patches, particularly those surrounding water bodies. We also report on the characteristics of the capture-release strategy and provide our observations indicating no escalated aggression by leopards' post-release. In conclusion, this study evaluates widely employed approaches to conflict mitigation and suggests the continuous review and assessment of management strategies for mitigating human-leopard conflicts. [ABSTRACT FROM AUTHOR]

Simple Summary: We studied the home ranges, movement, migration patterns, and habitat use of Common Cranes and Demoiselle Cranes using satellite telemetry. The average home ranges calculated in India were slightly greater than in their breeding areas. Common Crane-1 covered 12,982 km in 17 days to reach Russia. On the return journey, it covered a total distance of 14,873 km in 72 days. Common Crane-2 covered a total distance of 4500 km in 30 days to reach Kazakhstan. While returning to India, it covered 4922 km in 25 days. On the other hand, Demoiselle Crane-1 covered a total distance of 4968 km in 18 days during its northbound migration to Kazakhstan and 7394 km in 105 days to reach India. Demoiselle Crane-2 traveled a distance of 4310 km in 18 days to reach Kazakhstan and then made the return journey to India, covering a distance of 7757 km over a period of 128 days. Croplands and water bodies were the most important habitat variables influencing crane presence positively. The changing crop patterns from cereal grains to cotton, coupled with the shrinkage of water bodies within the study area, may raise concerns about their presence during winter in the near future. Using satellite telemetry, it is possible to track long-distance migrant birds with high accuracy and greater spatial coverage. However, prior to 2014, less than 1% of bird species in India had been monitored using this technology. Between January and February 2022, we deployed leg-mounted solar GPS/GSM satellite transmitters to Common Cranes and Demoiselle Cranes (two each) to study home ranges, movement, migration patterns, and habitat use. We used 95% kernels to define the total home range size and 50% kernels to delimit the core areas. The winter habitat use was assessed using Generalized Linear Models (GLM). The average home range of Common Cranes and Demoiselle Cranes was estimated as 161.22 ± 172.08 km2 and 971.40 ± 1023.57 km2, respectively. During migration, Common Crane-1 and Common Crane-2 traveled an average of 471.19 ± 442.42 and 176.97 ± 24.82 km per day, and Demoiselle Crane-1 and Demoiselle Crane-2 covered an average daily distance of 168.10 ± 203.77 and 192.97 ± 250.72 km, respectively. Water bodies and croplands were the most important habitat variables influencing crane presence positively. In recent years, the share of food grain crops within the study area has declined from 43% in 1994–1995 to 36% in 2014–2015, while the share of cotton crops has doubled from 11% to 20%, indicating a probable cause of concern in the near future. [ABSTRACT FROM AUTHOR]

The present study aimed to assess the population density, structure, and population change of nine wild prey species in the semi-arid landscape of Saurashtra, Gujarat, India. A total of eight sites, representing a gradient from highly protected woodlands and grasslands to unreserved grasslands, were selected for sampling. We employed the road transect methodology under a distance sampling framework to achieve our objectives. We evaluated the realized growth rate of the Gir ungulate population through linear regression analysis. Our findings revealed that deer species exhibited higher density and biomass in woodlands compared to grasslands and coastal forests. On the other hand, antelopes showed higher density and biomass in grasslands and coastal forests compared to woodlands. The density gradient of wild prey species was influenced by various factors, including habitat structure, social organization, grouping tendencies, and topography. Over the last four decades, the population of wild prey species in Gir showed minimal changes. Our study provides a comprehensive understanding of wild prey species' density and biomass patterns at the landscape level. The inclusion of findings from ecologically significant and unique areas, such as coastal forests, further enhances the importance of this study. The implications of this study extend beyond the conservation of wild prey species alone; they also contribute to the conservation of the large carnivore guild in the Saurashtra landscape. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is one of the deadliest subtypes of breast cancer (BC) for its high aggressiveness, heterogeneity, and hypoxic nature. Based on biological and clinical observations the TNBC related mortality is very high worldwide. Emerging studies have clearly demonstrated that hypoxia regulates the critical metabolic, developmental, and survival pathways in TNBC, which include glycolysis and angiogenesis. Alterations to these pathways accelerate the cancer stem cells (CSCs) enrichment and immune escape, which further lead to tumor invasion, migration, and metastasis. Beside this, hypoxia also manipulates the epigenetic plasticity and DNA damage response (DDR) to syndicate TNBC survival and its progression. Hypoxia fundamentally creates the low oxygen condition responsible for the alteration in Hypoxia-Inducible Factor-1alpha (HIF-1a) signaling within the tumor microenvironment, allowing tumors to survive and making them resistant to various therapies. Therefore, there is an urgent need for society to establish target-based therapies that overcome the resistance and limitations of the current treatment plan for TNBC. In this review article, we have thoroughly discussed the plausible significance of HIF-1a as a target in various therapeutic regimens such as chemotherapy, radiotherapy, immunotherapy, anti-angiogenic therapy, adjuvant therapy photodynamic therapy, adoptive cell therapy, combination therapies, antibody drug conjugates and cancer vaccines. Further, we also reviewed here the intrinsic mechanism and existing issues in targeting HIF-1a while improvising the current therapeutic strategies. This review highlights and discusses the future perspectives and the major alternatives to overcome TNBC resistance by targeting hypoxia-induced signaling. [ABSTRACT FROM AUTHOR]

Comparative studies on the diet of large felids in protected areas (PAs) and surrounding multi-use landscapes are important for their conservation. The Asiatic lion is an endangered felid distributed in Gir PA and the surrounding multi-use land matrix. Based on scat analyses, we assessed the dietary composition of Asiatic lions. The frequency of occurrence (FOO), biomass consumption model, dietary niche breadth and dietary overlap index was used to quantify diet. The Asiatic lion ate more wild prey (74%) than domestic livestock (26%) in the Gir PA. In contrast, lion diets comprised 51% wild prey and 42% domestic livestock in the multi-use land matrix. Sambar contributed most (38%) to the diet in PAs, while blue bull most (29%) in the multi-use land matrix. However, diet diversity and niche breadth were similar between these two areas. The dietary overlap in the lions' diet between these two areas was 0.52. The results suggest that large-size wild ungulates are the main prey species in Gir PA, while in the surrounding multi-use land matrix, both large wild ungulates and domestic livestock are the main prey. The present study may help future lion conservation management decisions. [ABSTRACT FROM AUTHOR]

Simple Summary: Asiatic lions are found in the Gir Protected Areas and surrounding multi-use land matrices in Saurashtra, Gujarat. Scientifically monitoring their movement and activity is vital for their conservation management. We used GPS radio-collars to study the movement and activity of 19 individual lions. This pilot study's results revealed how technology-driven scientific monitoring can help in conserving endangered species. From the conservation management perspective, we discussed the use of virtual geofence functions and alert generation to reduce the chances of endangered species mortality on linear infrastructures. We also presented a pilot case study on how GPS radio-telemetry helped in securing the safety of dispersing sub-adult coalition males extensively moving in a multi-use land matrix. This study may help develop baseline ecological information for impact assessment studies and predictive models for lion ecological requirements, habitat improvement and proactive and retrofitting mitigation measures. Endangered Asiatic lions (Panthera leo persica) are found in the Asiatic Lion Landscape, Gujarat, which includes protected areas and a multi-use land matrix. Therefore, monitoring lions' space-use and spatio-temporal location is vital for managing various facets of human−lion interaction. Our study demonstrates how this was achieved by tracking lions using GPS radio-collars, triggering prompt action via an efficient communication network across political and forest administrative boundaries. We monitored the movement of 19 individual lions for 436.5 ± 32 days and also derived the mean daily activity from three-axis accelerometer-based activity-sensing feature of a radio-collar. We also monitored geofence breaches. We proposed that immobility and movement are two aspects that generate management action on the ground. While the movement is related to ranging and dispersal, immobility is a situation related to either the animal's feeding or its health status. From a management standpoint, we discussed the efficacy of the virtual geofence in preventing accidents when lions moved and also presented the advantages of being able to track dispersal through a case study of sub-adult lions. To strengthen our response to lion immobility, we developed a predictive model that specifically highlights an individual lion's health status and makes the alert response more precise. In conclusion, we critically reviewed the capabilities provided by GPS telemetry and provide protocols that help in the conservation management of lions and that will also have a wider application. [ABSTRACT FROM AUTHOR]

Increased endothelial permeability leads to excessive exudation of plasma proteins and leukocytes in the interstitium, which characterizes several vascular diseases including acute lung injury. The myosin light chain kinase long (MYLK-L) isoform is canonically known to regulate the endothelial permeability by phosphorylating myosin light chain (MLC-P). Compared to the short MYLK isoform, MYLK-L contains an additional stretch of ~919 amino acid at the N-terminus of unknown function. We show that thapsigargin and thrombin-induced SOCE was markedly reduced in Mylk-L-/- endothelial cells (EC) or MYLK-L-depleted human EC. These agonists also failed to increase endothelial permeability in MYLK-L-depleted EC and Mylk-L-/- lungs, thus demonstrating the novel role of MYLK-L-induced SOCE in increasing vascular permeability. MYLK-L augmented SOCE by increasing endoplasmic reticulum (ER)-plasma membrane (PM) junctions and STIM1 translocation to these junctions. Transduction of N-MYLK domain (amino acids 1-919 devoid of catalytic activity) into Mylk-L-/- EC rescued SOCE to the level seen in control EC in a STIM1-dependent manner. N-MYLK-induced SOCE augmented endothelial permeability without MLC-P via an actin-binding motif, DVRGLL. Liposomal-mediated delivery of N-MYLK mutant but not DVRGLL-N-MYLK mutant in Mylk-L-/- mice rescued vascular permeability increase in response to endotoxin, indicating that targeting of DVRGLL motif within MYLK-L may limit SOCE-induced vascular hyperpermeability. [ABSTRACT FROM AUTHOR]

Background The carpal tunnel is a groove that spans the palm as a 'U.' The ulnar and radial sides of the wrist are made up of the scaphoid tubercle and trapezium while the palmar aspect is made up of carpal bones. Our study aimed to see whether there were differences in carpal tunnel size between men and women. Material and methods The study was conducted on 65 healthy adults, 13 (20%) were males and 52 (80%) were females (both non-pregnant and pregnant). Inclusion criteria were healthy adults and bilaterally symmetrical limbs. Exclusion criteria were chronic disease, diabetes, hypertension, immunological disorders, any visible abnormalities, and a history of upper extremity pain on either side. A high-resolution ultrasound machine with a linear transducer was used to perform an ultrasound scan of the carpal tunnel. The anteroposterior dimension was measured at the midline, or along the axis of the middle finger, and the transverse diameter was measured at the midpoint of the flexor retinaculum. The cross-sectional area of the tunnel was measured at its largest diameter within the carpal tunnel. All the dimensions were measured in centimeters. Results The mean transverse diameter of the right side was 1.824 ± 0.223 cm (p-value 0.002) and of the left side was 1.742 ± 0.197 cm (p-value 0.004). The mean cross-sectional area of the carpal tunnel on the right side was 1.417 ± 0.379 cm 2 (p-value 0.008) and on the left side was 1.306 ± 0.303 cm 2  (p-value 0.004), respectively. Age, sex, weight, and BMI were discussed. The carpal tunnels of females were found to be comparatively squarer and smaller than those of males. Conclusion The transverse diameter and cross-sectional area of the carpal tunnel and their correlation with carpal tunnel syndrome are predicted by age, sex, weight, and BMI. Both sexes had the same wrist ratio., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Rani et al.)

The immune system, a central player in maintaining homeostasis, emerges as a pivotal factor in the pathogenesis and progression of two seemingly disparate yet interconnected categories of diseases: autoimmunity and cancer. This chapter delves into the intricate and multifaceted role of the immune system, particularly T cells, in orchestrating responses that govern the delicate balance between immune surveillance and self-tolerance. T cells, pivotal immune system components, play a central role in both diseases. In autoimmunity, aberrant T cell activation drives damaging immune responses against normal tissues, while in cancer, T cells exhibit suppressed responses, allowing the growth of malignant tumors. Immune checkpoint receptors, example, initially explored in autoimmunity, now revolutionize cancer treatment via immune checkpoint blockade (ICB). Though effective in various tumors, ICB poses risks of immune-related adverse events (irAEs) akin to autoimmunity. This chapter underscores the importance of understanding tumor-associated antigens and their role in autoimmunity, immune checkpoint regulation, and their implications for both diseases. It also explores autoimmunity resulting from cancer immunotherapy and shared molecular pathways in solid tumors and autoimmune diseases, highlighting their interconnectedness at the molecular level. Additionally, it sheds light on common pathways and epigenetic features shared by autoimmunity and cancer, and the potential of repurposing drugs for therapeutic interventions. Delving deeper into these insights could unlock therapeutic strategies for both autoimmunity and cancer., (Copyright © 2024. Published by Elsevier Inc.)

Triple-negative breast cancer (TNBC) poses a significant clinical challenge due to its aggressive nature and limited therapeutic options. The interplay between DNA damage response (DDR) mechanisms and the emergence of neoantigens represents a promising avenue for developing targeted immunotherapeutic strategies and vaccines for TNBC. The DDR is a complex network of cellular mechanisms designed to maintain genomic integrity. In TNBC, where genetic instability is a hallmark, dysregulation of DDR components plays a pivotal role in tumorigenesis and progression. This review explores the intricate relationship between DDR and neoantigens, shedding light on the potential vulnerabilities of TNBC cells. Neoantigens, arising from somatic mutations in cancer cells, represent unique antigens that can be recognized by the immune system. TNBC's propensity for genomic instability leads to an increased mutational burden, consequently yielding a rich repertoire of neoantigens. The convergence of DDR and neoantigens in TNBC offers a distinctive opportunity for immunotherapeutic targeting. Immunotherapy has revolutionized cancer treatment by harnessing the immune system to selectively target cancer cells. The unique immunogenicity conferred by DDR-related neoantigens in TNBC positions them as ideal targets for immunotherapeutic interventions. This review also explores various immunotherapeutic modalities, including immune checkpoint inhibitors (ICIs), adoptive cell therapies, and cancer vaccines, that leverage the DDR and neoantigen interplay to enhance anti-tumor immune responses. Moreover, the potential for developing vaccines targeting DDR-related neoantigens opens new frontiers in preventive and therapeutic strategies for TNBC. The rational design of vaccines tailored to the individual mutational landscape of TNBC holds promise for precision medicine approaches. In conclusion, the convergence of DDR and neoantigens in TNBC presents a compelling rationale for the development of innovative immunotherapies and vaccines. Understanding and targeting these interconnected processes may pave the way for personalized and effective interventions, offering new hope for patients grappling with the challenges posed by TNBCs., (Copyright © 2024. Published by Elsevier Inc.)

Colorectal cancer represents the third most common cancer type worldwide and is a leading cause of cancer-related mortality in the United States and Western countries. Rodent models have been invaluable to study the etiology of colorectal cancer and to test novel chemoprevention avenues. In the past, the laboratory mouse has become one of the best preclinical models for these studies due to the availability of genetic information for commonly used mouse strains with well-established and precise gene targeting and transgenic techniques. Well-established chemical mutagenesis technologies are also being used to develop mouse and rat models of colorectal cancer for prevention and treatment studies. In addition, xenotransplantation of cancer cell lines and patient-derived xenografts has been useful for preclinical prevention studies and drug development. This review focuses on the recent use of rodent models to evaluate the utility of novel strategies in the prevention of colon cancers including immune prevention approaches and the manipulation of the intestinal microbiota., (©2023 American Association for Cancer Research.)

Endangered Asiatic lions ( Panthera leo persica ) are found in the Asiatic Lion Landscape, Gujarat, which includes protected areas and a multi-use land matrix. Therefore, monitoring lions' space-use and spatio-temporal location is vital for managing various facets of human-lion interaction. Our study demonstrates how this was achieved by tracking lions using GPS radio-collars, triggering prompt action via an efficient communication network across political and forest administrative boundaries. We monitored the movement of 19 individual lions for 436.5 ± 32 days and also derived the mean daily activity from three-axis accelerometer-based activity-sensing feature of a radio-collar. We also monitored geofence breaches. We proposed that immobility and movement are two aspects that generate management action on the ground. While the movement is related to ranging and dispersal, immobility is a situation related to either the animal's feeding or its health status. From a management standpoint, we discussed the efficacy of the virtual geofence in preventing accidents when lions moved and also presented the advantages of being able to track dispersal through a case study of sub-adult lions. To strengthen our response to lion immobility, we developed a predictive model that specifically highlights an individual lion's health status and makes the alert response more precise. In conclusion, we critically reviewed the capabilities provided by GPS telemetry and provide protocols that help in the conservation management of lions and that will also have a wider application., Competing Interests: The authors have no conflicts of interest to declare relevant to this article’s content.

Introduction:  Correct localization of the sacral hiatus is essential for administering a successful caudal epidural block. The present study was undertaken to find out the anatomical variations of sacral hiatus by a metrical method so that it could help anaesthesiologists in the clinical field., Materials and Methods: The study was performed on 140 (83 male and 57 female) adult human sacra. Various parameters of the sacrum studied were as follows: the shape of the hiatus, length of the sacral hiatus, transverse width at the base and anteroposterior diameter at the level of the apex. For each parameter, the mean value (calculated in mm), standard deviation, range and percentage of bones identified correctly were calculated., Results: Various shapes of sacral hiatus were observed, including inverted "U" in 73 (52.14%), inverted "V" in 33 (23.57%), irregular in 10 (7.14%), elongated in 10 (7.14%) and dumbbell-shaped in 12 (8.57%). Absent sacral hiatus was observed in two (1.43%) specimens. The mean value for the length of sacral hiatus from the apex to the midpoint of the base was found to be 23.26 mm in males and 22.38 mm in females. However, the parameter was found to be statistically not significant. The mean value for transverse width at the base of hiatus was found to be 14.19 mm in males and 13.54 mm in females. The mean value for the anteroposterior diameter of the sacral canal at the apex was found to be 4.57 mm in males and 4.32 mm in females. Both the above parameters were found to be statistically not significant., Summary and Conclusion: The anatomical knowledge of sacral hiatus and its variations are important in caudal epidural anaesthesia, and it may improve the success rate of caudal epidural anaesthesia., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Yadav et al.)