Treg Cells Promote the SREBP1-Dependent Metabolic Fitness of Tumor-Promoting Macrophages via Repression of CD8+ T Cell-Derived Interferon-γ.

Regulatory T (Treg) cells are crucial for immune homeostasis, but they also contribute to tumor immune evasion by promoting a suppressive tumor microenvironment (TME). Mice with Treg cell-restricted Neuropilin-1 deficiency show tumor resistance while maintaining peripheral immune homeostasis, thereby providing a controlled system to interrogate the impact of intratumoral Treg cells on the TME. Using this and other genetic models, we showed that Treg cells shaped the transcriptional landscape across multiple tumor-infiltrating immune cell types. Treg cells suppressed CD8+ T cell secretion of interferon-γ (IFNγ), which would otherwise block the activation of sterol regulatory element-binding protein 1 (SREBP1)-mediated fatty acid synthesis in immunosuppressive (M2-like) tumor-associated macrophages (TAMs). Thus, Treg cells indirectly but selectively sustained M2-like TAM metabolic fitness, mitochondrial integrity, and survival. SREBP1 inhibition augmented the efficacy of immune checkpoint blockade, suggesting that targeting Treg cells or their modulation of lipid metabolism in M2-like TAMs could improve cancer immunotherapy.

A fast-track surgery programme leads to timelier treatment and higher resection rates in pancreatic cancer.

BACKGROUND: The aim was to perform a propensity-matched comparison of patients with pancreatic cancer undergoing surgery, with and without biliary stenting and an intention to treat analysis of long-term survival between the two groups. METHODS: This was an observational study of a cohort of consecutive patients presenting with obstructive jaundice and undergoing pancreatoduodenectomy for pancreatic and periampullary malignancies between November 2015 and May 2019. RESULTS: In this study of 216 consecutive operable patients, 70 followed the fast-track pathway and 146 had pre-operative biliary drainage. All 70 patients in the FT group and 122 out of 146 in the PBD group proceeded to surgery (100% and 83.6% respectively, p = 0.001). Interval time from diagnostic CT scan to surgery and from MDT decision to treat to surgery was shorter in the FT group, (median 8 vs 43 days p < 0.001 and 3 vs 36 days p < 0.001 respectively) as was the overall time from diagnostic CT to adjuvant treatment (88 vs 121 days p < 0.001). Postoperative outcomes including complications, readmission and mortality rates were comparable in the two groups. There was no difference in survival. CONCLUSION: For a person with pancreatic cancer who is proceeding to surgery, the best approach is to avoid pre-operative biliary drainage.

High Flux Through the Oxidative Pentose Phosphate Pathway Lowers Efficiency in Developing Camelina Seeds.

Many seeds are green during development, and light has been shown to play a role in the efficiency with which maternally supplied substrates are converted into storage compounds. However, the effects of light on the fluxes through central metabolism that determine this efficiency are poorly understood. Here, we used metabolic flux analysis to determine the effects of light on central metabolism in developing embryos of false flax (Camelina sativa). Metabolic efficiency in C. sativa is of interest because, despite its growing importance as a model oilseed and engineering target and its potential as a biofuel crop, its yields are lower than other major oilseed species. Culture conditions under which steady-state growth and composition of developing embryos match those in planta were used to quantify substrate uptake and respiration rates. The carbon conversion efficiency (CCE) was 21% ± 3% in the dark and 42% ± 4% under high light. Under physiological illumination, the CCE (32% ± 2%) was substantially lower than in green and nongreen oilseeds studied previously. 13C and 14C isotopic labeling experiments were used together with computer-aided modeling to map fluxes through central metabolism. Fluxes through the oxidative pentose phosphate pathway (OPPP) were the principal source of CO2 production and strongly negatively correlated with CCE across light levels. OPPP fluxes were greatly in excess of demand for NAD(P)H for biosynthesis and larger than those measured in other systems. Excess reductant appears to be dissipated via cyanide-insensitive respiration. OPPP enzymes therefore represent a potential target for increasing efficiency and yield in C. sativa.

Human liver umbilical fissure variants: pons hepatis (ligamentum teres tunnel).

PURPOSE: In the classical description of normal liver anatomy, the umbilical fissure is a long, narrow groove that receives the ligamentum teres hepatis. The pons hepatis is an anatomic variant, where the umbilical fissure is converted into a tunnel by an overlying bridge of liver parenchyma. We carried out a study to evaluate the existing variations of the umbilical fissure in a Caribbean population. METHODS: We observed all consecutive autopsies performed at a facility in Jamaica and selected cadavers with a pons hepatis for detailed study. A pons hepatis was considered present when the umbilical fissure was covered by hepatic parenchyma. We recognized two variants: an open-type (incomplete) pons hepatis in which the umbilical fissure was incompletely covered by parenchyma ≤ 2 cm in length and a closed type (complete) pons hepatis in which the umbilical fissure was covered by a parenchymal bridge > 2 cm and thus converted into a tunnel. We measured the length (distance from transverse fissure to anterior margin of the parenchymatous bridge), width (extension across the umbilical fissure in a coronal plane) and thickness (distance from the visceral surface to the hepatic surface measured at the mid-point of the parenchymal bridge in a sagittal plane) of each pons hepatis. A systematic literature review was also performed to retrieve data from relevant studies. The raw data from these retrieved studies was used to calculate the global point prevalence of pons hepatis and compared the prevalence in our population. RESULTS: Of 66 autopsies observed, a pons hepatis was present in 27 (40.9%) cadavers. There were 15 complete variants, with a mean length of 34.66 mm, mean width of 16.98 mm and mean thickness of 10.98 mm. There were 12 incomplete variants, with a mean length of 17.02 mm, width of 17.03 mm and thickness of 9.56 mm. The global point prevalence of the pons hepatis (190/5515) was calculated to be or 3.45% of the global population. CONCLUSIONS: We have proposed a classification of the pons hepatis that is reproducible and clinically relevant. This allowed us to identify a high prevalence of pons hepatis (41%) in this Afro-Caribbean population that is significantly greater than the global prevalence (3.45%; P < 0.0001).

Correction: Genome, Functional Gene Annotation, and Nuclear Transformation of the Heterokont Oleaginous Alga Nannochloropsis oceanica CCMP1779.

[This corrects the article DOI: 10.1371/journal.pgen.1003064.].

Eyelid Lesion as a Presenting Sign of Pancreatic Adenocarcinoma.

Eyelid metastases are relatively rare, and they can occasionally lead the way to an unknown primary malignancy elsewhere. The authors report a case of 65-year-old diabetic gentleman with a right-sided eyelid lesion that was present for 1 month and turned out to be a presenting sign of a previously undiagnosed pancreatic adenocarcinoma. The eyelid mass had been treated elsewhere for 2 weeks for a presumed infectious lesion, using systemic antibiotics and was then referred to us in view of no response. The right-sided lesion involving the subbrow and eyelid area was tender and showed surface ulceration, as well as induration with scabbing. An incision biopsy of the mass was performed followed by computed tomography imaging. Histopathologic findings were suggestive of adenocarcinoma of a probable secondary origin. A whole-body positron emission tomography (PET) scan along with raised serum tumor markers (carcinoembryonic antigen 125 [CEA 125] and carbohydrate antigen 19-9 [CA-19-9]) was helpful in diagnosing a stage IV probable primary carcinoma of the pancreas, with metastasis to paraaortic nodes, liver, lungs, and eyelid. After a detailed systemic work-up, the patient was put on systemic chemotherapy with carboplatin and capacitabane. He responded well to the treatment. At a follow up of 12 months, upon clinical examination and PET imaging, he showed a complete resolution of eyelid, lung, and liver disease and a near-complete resolution of the pancreatic lesion. This case delineates the role of a prompt biopsy and histopathologic evaluation of an atypical eyelid mass in diagnosing asymptomatic primary malignancy.

Primary Orbital Leiomyosarcoma in an Adult Male.

A 71-year-old male presented with a history of noticing gradual painless progressive proptosis along with a pinkish mass seen on the outer aspect of his left eyeball. Orbital CT revealed a fairly defined homogenous lesion, abutting the left eyeball and involving the lateral orbit reaching almost till orbital apex. Histopathology analysis aided with immunohistochemistry after an incision biopsy was consistent with leiomyosarcoma. Positron emission tomography scan ruled out presence of any distant primary or metastatic tumor. He underwent eyelid sparing total orbital exenteration with confirmed tumor free soft-tissue margins. He is doing well at 5 months of follow-up with no sign of local recurrence or distant metastasis. Primary orbital leiomyosarcoma is a rare tumor. It is mainly found in older woman; it is even rarer in males. Complete surgical excision with tumor free margins is the recommended treatment. Histopathology and immunohistochemistry are valuable in diagnosis and management.

The response of Chlamydomonas reinhardtii to nitrogen deprivation: a systems biology analysis.

Drastic alteration in macronutrients causes large changes in gene expression in the photosynthetic unicellular alga Chlamydomonas reinhardtii. Preliminary data suggested that cells follow a biphasic response to this change hinging on the initiation of lipid accumulation, and we hypothesized that drastic repatterning of metabolism also followed this biphasic modality. To test this hypothesis, transcriptomic, proteomic, and metabolite changes that occur under nitrogen (N) deprivation were analyzed. Eight sampling times were selected covering the progressive slowing of growth and induction of oil synthesis between 4 and 6 h after N deprivation. Results of the combined, systems-level investigation indicated that C. reinhardtii cells sense and respond on a large scale within 30 min to a switch to N-deprived conditions turning on a largely gluconeogenic metabolic state, which then transitions to a glycolytic stage between 4 and 6 h after N depletion. This nitrogen-sensing system is transduced to carbon- and nitrogen-responsive pathways, leading to down-regulation of carbon assimilation and chlorophyll biosynthesis, and an increase in nitrogen metabolism and lipid biosynthesis. For example, the expression of nearly all the enzymes for assimilating nitrogen from ammonium, nitrate, nitrite, urea, formamide/acetamide, purines, pyrimidines, polyamines, amino acids and proteins increased significantly. Although arginine biosynthesis enzymes were also rapidly up-regulated, arginine pool size changes and isotopic labeling results indicated no increased flux through this pathway.

The regulation of photosynthetic structure and function during nitrogen deprivation in Chlamydomonas reinhardtii.

The accumulation of carbon storage compounds by many unicellular algae after nutrient deprivation occurs despite declines in their photosynthetic apparatus. To understand the regulation and roles of photosynthesis during this potentially bioenergetically valuable process, we analyzed photosynthetic structure and function after nitrogen deprivation in the model alga Chlamydomonas reinhardtii. Transcriptomic, proteomic, metabolite, and lipid profiling and microscopic time course data were combined with multiple measures of photosynthetic function. Levels of transcripts and proteins of photosystems I and II and most antenna genes fell with differing trajectories; thylakoid membrane lipid levels decreased, while their proportions remained similar and thylakoid membrane organization appeared to be preserved. Cellular chlorophyll (Chl) content decreased more than 2-fold within 24 h, and we conclude from transcript protein and (13)C labeling rates that Chl synthesis was down-regulated both pre- and posttranslationally and that Chl levels fell because of a rapid cessation in synthesis and dilution by cellular growth rather than because of degradation. Photosynthetically driven oxygen production and the efficiency of photosystem II as well as P700(+) reduction and electrochromic shift kinetics all decreased over the time course, without evidence of substantial energy overflow. The results also indicate that linear electron flow fell approximately 15% more than cyclic flow over the first 24 h. Comparing Calvin-Benson cycle transcript and enzyme levels with changes in photosynthetic (13)CO2 incorporation rates also pointed to a coordinated multilevel down-regulation of photosynthetic fluxes during starch synthesis before the induction of high triacylglycerol accumulation rates.

Identification of regulatory network hubs that control lipid metabolism in Chlamydomonas reinhardtii.

Microalgae-based biofuels are promising sources of alternative energy, but improvements throughout the production process are required to establish them as economically feasible. One of the most influential improvements would be a significant increase in lipid yields, which could be achieved by altering the regulation of lipid biosynthesis and accumulation. Chlamydomonas reinhardtii accumulates oil (triacylglycerols, TAG) in response to nitrogen (N) deprivation. Although a few important regulatory genes have been identified that are involved in controlling this process, a global understanding of the larger regulatory network has not been developed. In order to uncover this network in this species, a combined omics (transcriptomic, proteomic and metabolomic) analysis was applied to cells grown in a time course experiment after a shift from N-replete to N-depleted conditions. Changes in transcript and protein levels of 414 predicted transcription factors (TFs) and transcriptional regulators (TRs) were monitored relative to other genes. The TF and TR genes were thus classified by two separate measures: up-regulated versus down-regulated and early response versus late response relative to two phases of polar lipid synthesis (before and after TAG biosynthesis initiation). Lipidomic and primary metabolite profiling generated compound accumulation levels that were integrated with the transcript dataset and TF profiling to produce a transcriptional regulatory network. Evaluation of this proposed regulatory network led to the identification of several regulatory hubs that control many aspects of cellular metabolism, from N assimilation and metabolism, to central metabolism, photosynthesis and lipid metabolism.

Extrahepatic arteries of the human liver - anatomical variants and surgical relevancies.

The purpose of our study was to investigate the anatomical variations of the extrahepatic arterial structures of the liver with particular attention to rare variations and their potential impact on liver surgery. A total of 50 human abdominal organ complexes were used to prepare corrosion casts. A multicomponent resin mixture was injected into the abdominal aorta. The portal vein was injected with a different colored resin in 16 cases. Digestion of soft tissues was achieved using cc. KOH solution at 60-65 °C. Extrahepatic arterial variations were classified according to Michels. All specimens underwent 3D volumetric CT reconstruction. Normal anatomy was seen in 42% of cases, and variants were seen in the other 58%. No Michels type VI or X variations were present; however, in 18% of cases the extrahepatic arterial anatomy did not fit into Michels' classification. We report four new extrahepatic arterial variations. In contrast to the available data, normal anatomy was found much less frequently, whereas the prevalence of unclassified arterial variations was higher. We detected four previously unknown variations. Our data may contribute to the reduction of complications during surgical and radiological interventions in the upper abdomen.

Optimal line of hepatotomy for left lateral living donor liver transplantation according to the anatomical variations of left hepatic duct system.

Multiple duct anastomoses during LLS transplantation increase the incidence of biliary complications. The optimal plane of hepatotomy that results in the least number of bile ducts at the surface was investigated according to LHD variations. Ducts of 30 human livers were injected with resin and LHD branching on 3D-CT reconstructions were analyzed. Ducts on the virtual hepatotomy surface were estimated in three splitting lines. Variations with subtypes were described. Ia (66.7%): ducts from segments (S.) II-III form a common trunk and S.IV duct joins it. Ib (10%): common trunk formed by ducts from S.II-S.III while S.IV duct joins the common hepatic duct. IIa (16.67%): S.IV duct drains into S.III duct. IIc (3.33%): S.IV duct drains into both S.II and S.III ducts. III (3.33%): trifurcation of S.II, S.III and S.IV ducts. When the virtual hepatotomy line was on the FL, there was a single duct for the anastomosis in 30% of cases but two, three, or four ducts in 53.3%, 10%, and 3.3%, respectively. Division 1 cm to the right of the FL resulted in one duct (70%), but S.IV duct injury may occur. LLS hepatotomy should not necessarily be performed along the FL. Variations must be taken into consideration to minimize the number of biliary anastomoses during liver implantation.

Genome, functional gene annotation, and nuclear transformation of the heterokont oleaginous alga Nannochloropsis oceanica CCMP1779.

Unicellular marine algae have promise for providing sustainable and scalable biofuel feedstocks, although no single species has emerged as a preferred organism. Moreover, adequate molecular and genetic resources prerequisite for the rational engineering of marine algal feedstocks are lacking for most candidate species. Heterokonts of the genus Nannochloropsis naturally have high cellular oil content and are already in use for industrial production of high-value lipid products. First success in applying reverse genetics by targeted gene replacement makes Nannochloropsis oceanica an attractive model to investigate the cell and molecular biology and biochemistry of this fascinating organism group. Here we present the assembly of the 28.7 Mb genome of N. oceanica CCMP1779. RNA sequencing data from nitrogen-replete and nitrogen-depleted growth conditions support a total of 11,973 genes, of which in addition to automatic annotation some were manually inspected to predict the biochemical repertoire for this organism. Among others, more than 100 genes putatively related to lipid metabolism, 114 predicted transcription factors, and 109 transcriptional regulators were annotated. Comparison of the N. oceanica CCMP1779 gene repertoire with the recently published N. gaditana genome identified 2,649 genes likely specific to N. oceanica CCMP1779. Many of these N. oceanica-specific genes have putative orthologs in other species or are supported by transcriptional evidence. However, because similarity-based annotations are limited, functions of most of these species-specific genes remain unknown. Aside from the genome sequence and its analysis, protocols for the transformation of N. oceanica CCMP1779 are provided. The availability of genomic and transcriptomic data for Nannochloropsis oceanica CCMP1779, along with efficient transformation protocols, provides a blueprint for future detailed gene functional analysis and genetic engineering of Nannochloropsis species by a growing academic community focused on this genus.

Rescue from complications after pancreaticoduodenectomies at a low-volume Caribbean center: Value of tailored peri-pancreatectomy protocols.

BACKGROUND: Pancreaticoduodenectomy (PD) is a technically complex operation, with a relatively high risk for complications. The ability to rescue patients from post-PD complications is as a recognized quality measure. Tailored protocols were instituted at our low volume facility in the year 2013. AIM: To document the rate of rescue from post-PD complications with tailored protocols in place as a measure of quality. METHODS: A retrospective audit was performed to collect data from patients who experienced major post-PD complications at a low volume pancreatic surgery unit in Trinidad and Tobago between January 1, 2013 and June 30, 2023. Standardized definitions from the International Study Group of Pancreatic Surgery were used to define post-PD complications, and the modified Clavien-Dindo classification was used to classify post-PD complications. RESULTS: Over the study period, 113 patients at a mean age of 57.5 years (standard deviation [SD] ± 9.23; range: 30-90; median: 56) underwent PDs at this facility. Major complications were recorded in 33 (29.2%) patients at a mean age of 53.8 years (SD: ± 7.9). Twenty-nine (87.9%) patients who experienced major morbidity were salvaged after aggressive treatment of their complication. Four (3.5%) died from bleeding pseudoaneurysm (1), septic shock secondary to a bile leak (1), anastomotic leak (1), and myocardial infarction (1). There was a significantly greater salvage rate in patients with American Society of Anesthesiologists scores ≤ 2 (93.3% vs 25%; P = 0.0024). CONCLUSION: This paper adds to the growing body of evidence that volume alone should not be used as a marker of quality for patients requiring PD. Despite low volumes at our facility, we demonstrated that 87.9% of patients were rescued from major complications. We attributed this to several factors including development of rescue protocols, the competence of the pancreatic surgery teams and continuous, and adaptive learning by the entire institution, culminating in the development of tailored peri-pancreatectomy protocols.

Identifying regions of importance in wall-bounded turbulence through explainable deep learning.

Despite its great scientific and technological importance, wall-bounded turbulence is an unresolved problem in classical physics that requires new perspectives to be tackled. One of the key strategies has been to study interactions among the energy-containing coherent structures in the flow. Such interactions are explored in this study using an explainable deep-learning method. The instantaneous velocity field obtained from a turbulent channel flow simulation is used to predict the velocity field in time through a U-net architecture. Based on the predicted flow, we assess the importance of each structure for this prediction using the game-theoretic algorithm of SHapley Additive exPlanations (SHAP). This work provides results in agreement with previous observations in the literature and extends them by revealing that the most important structures in the flow are not necessarily the ones with the highest contribution to the Reynolds shear stress. We also apply the method to an experimental database, where we can identify structures based on their importance score. This framework has the potential to shed light on numerous fundamental phenomena of wall-bounded turbulence, including novel strategies for flow control.

Simultaneous Quantitation and Discovery (SQUAD) Analysis: Combining the Best of Targeted and Untargeted Mass Spectrometry-Based Metabolomics.

Untargeted and targeted approaches are the traditional metabolomics workflows acquired for a wider understanding of the metabolome under focus. Both approaches have their strengths and weaknesses. The untargeted, for example, is maximizing the detection and accurate identification of thousands of metabolites, while the targeted is maximizing the linear dynamic range and quantification sensitivity. These workflows, however, are acquired separately, so researchers compromise either a low-accuracy overview of total molecular changes (i.e., untargeted analysis) or a detailed yet blinkered snapshot of a selected group of metabolites (i.e., targeted analysis) by selecting one of the workflows over the other. In this review, we present a novel single injection simultaneous quantitation and discovery (SQUAD) metabolomics that combines targeted and untargeted workflows. It is used to identify and accurately quantify a targeted set of metabolites. It also allows data retro-mining to look for global metabolic changes that were not part of the original focus. This offers a way to strike the balance between targeted and untargeted approaches in one single experiment and address the two approaches' limitations. This simultaneous acquisition of hypothesis-led and discovery-led datasets allows scientists to gain more knowledge about biological systems in a single experiment.

Social determinants of diabetic retinopathy and impact of sight-threatening diabetic retinopathy: A study from Pune, India.

Purpose: Diabetes-related retinopathy is the leading cause of blindness in India. The study was carried out with the purpose of studying the association of sight-threatening diabetic retinopathy (STDR) with socioeconomic factors and demonstrating the impact of STDR on the affected individual. Methods: A mixed methods (quantitative and qualitative) research design was used. The study participants were divided into two groups for quantitative analysis. The control group consisted of non-sight-threatening diabetic retinopathy, whereas the study group consisted of sight-threatening diabetic retinopathy. Apart from demographics, data on comorbidities, type and duration of diabetes mellitus (DM), health insurance status, and socioeconomic data were collected from each individual. A statistical test (Chi-square) was performed to study the association between socioeconomic (SE) classes and STDR. For the qualitative part, a few people were chosen. Face-to-face interviews were conducted in depth. Results: A total of 207 individuals, were recruited, of which 69 had STDR and the remaining 138 had non-STDR. The incidence of STDR was high among patients with lower socioeconomic class (SEC) (upper lower and lower), and univariate analysis revealed a strong association between STDR and SEC, the presence of comorbidities, presence of health insurance, type and duration of DM, and P value <0.05. SEC, in contrast, emerged as an independent risk factor for STDR in multivariate analysis. STDR had a devastating effect on all patients interviewed. The financial impact was most likely the most severe. Conclusion: People with lower SEC are more likely to suffer from STDR-related vision loss. The impact of such vision loss on individuals is multifaceted, including a negative impact on social and work life, psychological well-being, and, most importantly, a significant financial impact.

A comparative study to evaluate the effect of various postoperative treatment protocols on dry eye and patient satisfaction after phacoemulsification.

Purpose: Foreign body sensation and irritation are common after cataract surgery, as is the exacerbation of dry eye disease if present. This study compared postoperative dry eye treatments and patient satisfaction. Methods: Age-related cataract patients undergoing phacoemulsification were recruited and were divided randomly into 4 postoperative treatment groups: Group A: Antibiotic + Steroids; Group B: Antibiotic + Steroids + Mydriatic; Group C: Antibiotic + Steroids + Mydriatic + Non-steroidal Ant-inflammatory drugs (NSAIDs); Group D: Antibiotic + Steroids + Mydriatic + NSAID + Tear substitute. Patients were assessed at 1, 3, and 5 weeks post-operatively for uncorrected distance and near vision, best corrected visual acuity (BCVA) for distance and near, Schirmer's-1 test, and Tear Film Break-Up Time test. At each visit, patients were assessed for dry eye-related subjective parameters using Ocular Surface Disease Index questionnaire. Results: Study participants numbered 163. (87 male and 76 female patients). No statistically significant difference was present in visual acuity for near and distance. The mean values of Schirmer's test and TFBUT were better in group D patients at each postoperative visit, with significant differences noted in comparison with other groups. The patient response to pain and dry eye symptoms was superior in groups C and D, with group D producing the best results. Compared to group A, patients in groups C and D were more satisfied with their vision and surgery. Conclusion: The addition of tear substitutes to steroids and NSAIDs has been associated with decreased dry eye-related symptoms and a better subjective feeling of vision, although no significant difference was noted in vision measured objectively.