Epidemiology, microbiology, and diagnosis of infection in diabetic ketoacidosis and hyperosmolar hyperglycemic syndrome: A multicenter retrospective observational study.

AIMS: We investigated the characteristics of infection and the utility of inflammatory markers in diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic syndrome (HHS). METHODS: A multicenter, retrospective observational study in 21 acute-care hospitals was conducted in Japan. This study included adult hospitalized patients with DKA and HHS. We analyzed the diagnostic accuracy of markers including C-reactive protein (CRP) and procalcitonin (PCT) for bacteremia. Multiple regression models were created for estimating bacteremia risk factors. RESULTS: A total of 771 patients, including 545 patients with DKA and 226 patients with HHS, were analyzed. The mean age was 58.2 (SD, 19.3) years. Of these, 70 tested positive for blood culture. The mortality rates of those with and without bacteremia were 14 % and 3.3 % (P-value < 0.001). The area under the curve (AUC) of CRP and PCT for diagnosis of bacteremia was 0.85 (95 %CI, 0.81 to 0.89) and 0.76 (95 %CI, 0.60 to 0.92), respectively. Logistic regression models identified older age, altered level of consciousness, hypotension, and higher CRP as risk factors for bacteremia. CONCLUSIONS: The mortality rate was higher in patients with bacteremia than patients without it. CRP, rather than PCT, may be valid for diagnosing bacteremia in hyperglycemic emergencies. TRIAL REGISTRATION: This study is registered in the UMIN clinical trial registration system (UMIN000025393, Registered December 23, 2016).

ACA-28, an ERK MAPK Signaling Modulator, Exerts Anticancer Activity through ROS Induction in Melanoma and Pancreatic Cancer Cells.

The extracellular signal-regulated kinase (ERK) MAPK pathway is dysregulated in various human cancers and is considered an attractive therapeutic target for cancer. Therefore, several inhibitors of this pathway are being developed, and some are already used in the clinic. We have previously identified an anticancer compound, ACA-28, with a unique property to preferentially induce ERK-dependent apoptosis in melanoma cells. To comprehensively understand the biological cellular impact induced by ACA-28, we performed a global gene expression analysis of human melanoma SK-MEL-28 cells exposed to ACA-28 using a DNA microarray. The transcriptome analysis identified nuclear factor erythroid 2-related factor 2 (Nrf2), a master transcription factor that combats oxidative stress, as the most upregulated genetic pathway after ACA-28 treatment. Consistently, ACA-28 showed properties to increase the levels of reactive oxygen species (ROS) as well as Nrf2 protein, which is normally repressed by proteasomal degradation and activated in response to oxidative stresses. Furthermore, the ROS scavenger N-acetyl cysteine significantly attenuated the anticancer activity of ACA-28. Thus, ACA-28 activates Nrf2 signaling and exerts anticancer activity partly via its ROS-stimulating property. Interestingly, human A549 cancer cells with constitutively high levels of Nrf2 protein showed resistance to ACA-28, as compared with SK-MEL-28. Transient overexpression of Nrf2 also increased the resistance of cells to ACA-28, while knockdown of Nrf2 exerted the opposite effect. Thus, upregulation of Nrf2 signaling protects cancer cells from ACA-28-mediated cell death. Notably, the Nrf2 inhibitor ML385 substantially enhanced the cell death-inducing property of ACA-28 in pancreatic cancer cells, T3M4 and PANC-1. Our data suggest that Nrf2 plays a key role in determining cancer cell susceptibility to ACA-28 and provides a novel strategy for cancer therapy to combine the Nrf2 inhibitor and ACA-28.

High versus low chloride load in adult hyperglycemic emergencies with acute kidney injury: a multicenter retrospective cohort study.

Hyperglycemic emergencies frequently lead to acute kidney injury (AKI) and require treatment with large amount of intravenous fluids. However, the effects of chloride loading on this population have not yet been investigated. We conducted a multicenter, retrospective, cohort study in 21 acute-care hospitals in Japan. The study included hospitalized adult patients with diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic syndrome (HHS) who had AKI upon arrival. The patients were classified into high and low chloride groups based on the amount of chloride administered within the first 48 h of their arrival. The primary outcome was recovery from AKI; secondary outcome was major adverse kidney events within 30 days (MAKE30), including mortality and prolonged renal failure. A total of 390 patients with AKI, including 268 (69%) with DKA and 122 (31%) with HHS, were included in the study. Using the criteria of Kidney Disease Improving Global Outcomes, the severity of AKI in the patients was Stage 1 (n = 159, 41%), Stage 2 (n = 121, 31%), and Stage 3 (n = 110, 28%). The analysis showed no significant difference between the two groups in recovery from AKI (adjusted hazard ratio, 0.96; 95% CI 0.72-1.28; P = 0.78) and in MAKE30 (adjusted odds ratio, 0.91; 95% CI 0.45-1.76; P = 0.80). Chloride loading with fluid administration had no significant impact on recovery from AKI in patients with hyperglycemic emergencies.Trial Registration This study was registered in the UMIN clinical trial registration system (UMIN000025393, registered December 23, 2016).

Deoxycytidine kinase inactivation enhances gemcitabine resistance and sensitizes mitochondrial metabolism interference in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is considered one of the most lethal forms of cancer. Although in the last decade, an increase in 5-year patient survival has been observed, the mortality rate remains high. As a first-line treatment for PDAC, gemcitabine alone or in combination (gemcitabine plus paclitaxel) has been used; however, drug resistance to this regimen is a growing issue. In our previous study, we reported MYC/glutamine dependency as a therapeutic target in gemcitabine-resistant PDAC secondary to deoxycytidine kinase (DCK) inactivation. Moreover, enrichment of oxidative phosphorylation (OXPHOS)-associated genes was a common property shared by PDAC cell lines, and patient clinical samples coupled with low DCK expression was also demonstrated, which implicates DCK in cancer metabolism. In this article, we reveal that the expression of most genes encoding mitochondrial complexes is remarkably upregulated in PDAC patients with low DCK expression. The DCK-knockout (DCK KO) CFPAC-1 PDAC cell line model reiterated this observation. Particularly, OXPHOS was functionally enhanced in DCK KO cells as shown by a higher oxygen consumption rate and mitochondrial ATP production. Electron microscopic observations revealed abnormal mitochondrial morphology in DCK KO cells. Furthermore, DCK inactivation exhibited reactive oxygen species (ROS) reduction accompanied with ROS-scavenging gene activation, such as SOD1 and SOD2. SOD2 inhibition in DCK KO cells clearly induced cell growth suppression. In combination with increased anti-apoptotic gene BCL2 expression in DCK KO cells, we finally reveal that venetoclax and a mitochondrial complex I inhibitor are therapeutically efficacious for DCK-inactivated CFPAC-1 cells in in vitro and xenograft models. Hence, our work provides insight into inhibition of mitochondrial metabolism as a novel therapeutic approach to overcome DCK inactivation-mediated gemcitabine resistance in PDAC patient treatment.

Effects of Static Hamstring Stretching on Maximal Sprint Speed and Relationship With Nordic Hamstring Strength.

This study aimed to determine the acute effects of static stretching of the hamstrings on maximal sprint speed and its spatiotemporal variables and lower-limb kinematics during the late swing phase, as well as the relationship with Nordic hamstring strength. The study had a within-participant experimental design. Sixteen healthy male college sprinters were asked to sprint 80 m without static stretching and with static stretching of the hamstrings for 4 × 30 s per leg before the sprint; both conditions were counterbalanced. The knee flexion peak torque was measured using the Nordic hamstring. The differences between no static stretching and static stretching as well as their relationship with Nordic hamstring strength were investigated. The results showed that the touchdown distance (p = .036) significantly increased following static stretching. Although not significant, maximal sprint speed decreased (p = .086), and the theoretical hamstring length (difference between knee angle and hip angle) at ipsilateral touchdown was greater (p = .069) following static stretching. In addition, a lower peak torque of the Nordic hamstring resulted in a more significant decrease in maximal sprint speed following static stretching. Therefore, static stretching of the hamstring just before sprinting may increase the theoretical hamstring length during the late swing phase at maximal sprint speed and induce kinematics that increases the hamstring strain injury risk. Moreover, it is suggested that improving the Nordic hamstring strength may help minimize the negative effects of static stretching on the hamstrings.

Association between hospital volume and in-hospital mortality in pediatric severe traumatic brain injury: a nationwide retrospective observational study in Japan.

OBJECTIVE: The objective of this study was to investigate the association between hospital volume and in-hospital mortality in pediatric patients with severe traumatic brain injury (TBI). METHODS: This retrospective cohort study used data from the Japan Trauma Data Bank between 2010 and 2018, specifically those of pediatric patients with severe TBI (Glasgow Coma Scale [GCS] score < 9 and head Abbreviated Injury Scale score > 2). Hospital volume was defined as the number of pediatric patients with severe TBI throughout the study period. Hospital volume was categorized as low (reference category: 1-9 patients), middle (10-17 patients), or high (> 18 patients) volume. Multivariate mixed-effects logistic regression analysis was performed to determine the association between hospital volume categories and in-hospital mortality. Subgroup analyses were performed using data on craniotomy and the presence of severe torso injuries. In the sensitivity analyses, patients with a GCS score of 3, interhospital transfer, and major intensive care unit complications were excluded. RESULTS: A total of 1148 pediatric patients with severe TBI, with a median age of 12 years (IQR 7-16 years), treated at 141 hospitals were included. In total, 236 patients (20.6%) died in the hospital. Multivariate analysis showed no significant association between hospital volume and in-hospital mortality (high volume: OR 1.15, 95% CI 0.80-1.64; middle volume: OR 0.89, 95% CI 0.62-1.26). Subgroup and sensitivity analyses showed similar results. CONCLUSIONS: Hospital volume may not be associated with in-hospital mortality in pediatric patients with severe TBI.

Clinical profile of patients with diabetic ketoacidosis and hyperglycemic hyperosmolar syndrome in Japan: a multicenter retrospective cohort study.

INTRODUCTION: Diabetic ketoacidosis (DKA) and hyperglycemic hyperosmolar syndrome (HHS) are life-threatening complications of diabetes mellitus. Their clinical profiles have not been fully investigated. METHODS: A multicenter retrospective cohort study was conducted in 21 acute care hospitals in Japan. Patients included were adults aged 18 or older who had been hospitalized from January 1, 2012, to December 31, 2016 due to DKA or HHS. The data were extracted from patient medical records. A four-group comparison (mild DKA, moderate DKA, severe DKA, and HHS) was performed to evaluate outcomes. RESULTS: A total of 771 patients including 545 patients with DKA and 226 patients with HHS were identified during the study period. The major precipitating factors of disease episodes were poor medication compliance, infectious diseases, and excessive drinking of sugar-sweetened beverages. The median hospital stay was 16 days [IQR 10-26 days]. The intensive care unit (ICU) admission rate was 44.4% (mean) and the rate at each hospital ranged from 0 to 100%. The in-hospital mortality rate was 2.8% in patients with DKA and 7.1% in the HHS group. No significant difference in mortality was seen among the three DKA groups. CONCLUSIONS: The mortality rate of patients with DKA in Japan is similar to other studies, while that of HHS was lower. The ICU admission rate varied among institutions. There was no significant association between the severity of DKA and mortality in the study population. TRIAL REGISTRATION: This study is registered in the UMIN clinical Trial Registration System (UMIN000025393, Registered 23th December 2016).

Laparoscopic cholecystectomy and common bile duct exploration for gallstone and common bile duct stone in a patient with a left-sided gallbladder: a case report.

Left-sided gallbladder is a rare finding that is mostly discovered incidentally during surgery and is often associated with anatomic anomalies. We herein report a case in which laparoscopic cholecystectomy and common bile duct exploration were achieved for an 89-year-old female patient with left-sided gallbladder. Surgery was carried out using our usual trocar position. Calot triangle was covered by the body of the gallbladder and could not be detected. We dissected the gallbladder from the fundus towards the neck. The cystic duct joined the common bile duct from the right side, and common bile duct exploration was performed routinely without perioperative comorbidities. Although the preoperative diagnosis rate is low and the risk of intraoperative bile duct injuries in patients with left-sided gallbladder is high, laparoscopic cholecystectomy and common bile duct exploration can be safely performed by understanding the location and bifurcation of the cystic duct.

A rare case of glial fibrillary acidic protein astrocytopathy that resolved spontaneously within a self-limited course.

Glial fibrillary acidic protein astrocytopathy is a form of autoimmune meningoencephalomyelitis. The presence of antibodies in spinal fluid against glial fibrillary acidic protein is necessary to diagnose the disease. There is no standard treatment and few cases of glial fibrillary acidic protein astrocytopathy have been reported. A 31-year-old healthy Japanese man presented to our emergency department with a 7-day history of fever and headache. He was in good general condition, without abnormalities on physical examination, and a general hematological examination revealed hyponatremia (130 mEq/L). Five days later, he was followed up and new subjective symptoms were noted: tremor in the right hand, constipation, sweating, and lightheadedness. Cerebrospinal fluid examination revealed a cell count of 57/µL (96 % mononuclear cells, 4 % multinuclear cells), elevated protein level (103 mg/dL), elevated adenosine deaminase level (15.0 U/L), negative polymerase chain reaction test results for herpes simplex virus and Mycobacterium tuberculosis, negative cerebrospinal fluid culture, and negative cerebrospinal fluid anti-acid bacteria culture, indicating aseptic meningitis. T1-weighted contrast-enhanced magnetic resonance imaging of the head showed a linear contrast effect perpendicular to the lateral ventricular wall and along the perivascular vessels spreading radially. Based on the presence of hyponatremia, history of movement disorder and autonomic symptoms, high adenosine deaminase level in cerebrospinal fluid, and findings on contrast-enhanced magnetic resonance imaging of the head, we suspected glial fibrillary acidic protein astrocytopathy and assessed anti-glial fibrillary acidic proteinαantibody in cerebrospinal fluid, which was positive, and diagnosed glial fibrillary acidic protein astrocytopathy. After careful follow-up with symptomatic treatment without immunosuppressive therapy, the fever, headache, tremor, and autonomic symptoms were improved over time. Contrast-enhanced magnetic resonance imaging of the head and findings of cerebrospinal fluid also showed improvement. glial fibrillary acidic protein astrocytopathy should be a differential diagnosis in patients with aseptic meningitis with movement disorders or autonomic symptoms and elevated cerebrospinal fluid adenosine deaminase. Careful follow-up without immunosuppressive treatment should be considered for patients with minimal neurologic symptoms as glial fibrillary acidic protein astrocytopathy may have a self-limiting course and resolve.

One-carbon metabolizing enzyme ALDH1L1 influences mitochondrial metabolism through 5-aminoimidazole-4-carboxamide ribonucleotide accumulation and serine depletion, contributing to tumor suppression.

Tumor cells generally require large amounts of nucleotides, and thus activate de novo purine synthesis (dnPS). In the dnPS reactions, 10-formyltetrahydorofolate (10-fTHF) supplied by one-carbon metabolism is utilized as a formyl group donor. We focused on aldehyde dehydrogenase 1 family member L1 (ALDH1L1), which metabolizes 10-fTHF to tetrahydrofolate and whose expression is often attenuated in hepatocellular carcinoma (HCC). We generated ALDH1L1-expressing HuH-7 cells to perform metabolome analysis and found that intracellular levels of serine were reduced and glycine was increased. In addition, 5-aminoimidazole-4-carboxamide ribonucleotide (ZMP), a dnPS intermediate, accumulated due to the consumption of 10-fTHF by ALDH1L1, which inhibited ZMP formylation. Importantly, ALDH1L1-expressing cells showed reduced ZMP sensitivity and higher mitochondrial activity. The suppression of mitochondrial serine catabolism by ALDH1L1 expression was speculated to be closely related to this phenotype. Gene set enrichment analysis utilizing The Cancer Genome Atlas data revealed that genes related to oxidative phosphorylation were enriched in HCC patients with high ALDH1L1 expression. Moreover, drug sensitivity data analysis demonstrated that HCC cell lines with low expression of ALDH1L1 were sensitive to ZMP and cordycepin, a structural analog of ZMP and AMP. Our study revealed that ZMP and AMP analogs might be effective in the pharmacotherapy of HCC patients with low expression of ALDH1L1.

MBTD1 preserves adult hematopoietic stem cell pool size and function.

Mbtd1 (mbt domain containing 1) encodes a nuclear protein containing a zinc finger domain and four malignant brain tumor (MBT) repeats. We previously generated Mbtd1-deficient mice and found that MBTD1 is highly expressed in fetal hematopoietic stem cells (HSCs) and sustains the number and function of fetal HSCs. However, since Mbtd1-deficient mice die soon after birth possibly due to skeletal abnormalities, its role in adult hematopoiesis remains unclear. To address this issue, we generated Mbtd1 conditional knockout mice and analyzed adult hematopoietic tissues deficient in Mbtd1. We observed that the numbers of HSCs and progenitors increased and Mbtd1-deficient HSCs exhibited hyperactive cell cycle, resulting in a defective response to exogenous stresses. Mechanistically, we found that MBTD1 directly binds to the promoter region of FoxO3a, encoding a forkhead protein essential for HSC quiescence, and interacts with components of TIP60 chromatin remodeling complex and other proteins involved in HSC and other stem cell functions. Restoration of FOXO3a activity in Mbtd1-deficient HSCs in vivo rescued cell cycle and pool size abnormalities. These findings indicate that MBTD1 is a critical regulator for HSC pool size and function, mainly through the maintenance of cell cycle quiescence by FOXO3a.

Endoscopic Lesions of Postoperative Anastomotic Area in Patients With Crohn's Disease in the Biologic Era: A Japanese Multi-Centre Nationwide Cohort Study.

BACKGROUND AND AIMS: Many patients have endoscopic evidence of recurrent Crohn's disease [CD] at 1 year after intestinal resection. These lesions predict future clinical recurrence. We endoscopically evaluated postoperative anastomotic lesions in CD patients from a large cohort of postoperative CD patients. METHODS: We retrospectively enrolled CD patients who underwent surgical resection between 2008 and 2013 at 19 inflammatory bowel disease [IBD]-specialist institutions. The initial analyses included patients who underwent ileocolonoscopy ~1 year after intestinal resection. Follow-up analyses assessed any changes in the endoscopic findings over time. We evaluated the postoperative endoscopic findings, which were classified into four categories [no lesion, mild, intermediate, severe] at the sites of the anastomotic line and peri-anastomosis. RESULTS: In total, 267 CD patients underwent postoperative ileocolonoscopy. Postoperative anastomotic lesions were widely detected in index ileocolonoscopy [61.0%] and were more frequently detected in follow-up ileocolonoscopy [74.9%]. Endoscopic severity also increased. Patients with intermediate or severe peri-anastomotic or anastomotic line lesions at the index ileocolonoscopy required significantly more interventions, including endoscopic dilatation or surgery, than patients with mild lesions or no lesions. CONCLUSIONS: Frequent anastomotic lesions were observed at the postoperative index ileocolonoscopy. These gradually increased for subsequent ileocolonoscopy, even in the biologic era. Regarding lesions on the anastomotic line, intermediate lesions on the anastomotic line [e.g. irregular or deep ulcers] might be considered recurrent disease, and mild lesions [e.g. linear superficial ulcers] might be considered non-recurrent disease. Prospective studies are needed to resolve this issue, including treatment enhancement.

Two case reports of two interventional radiology techniques for the treatment of stage II empyema: Hydrodissection and guidewire-dissection.

Empyema is an infection of the pleural space that is classified into 3 stages. Video-assisted thoracoscopic surgery is recommended as the first-line approach for stage II acute empyema. The purpose of video-assisted thoracoscopic surgery is also achieved with hydrodissection and guidewire-dissection by breaking the septa mechanically in the pleural cavity. Hydrodissection and guidewire-dissection are techniques in which a contrast medium is administered at high pressure and a guidewire is inserted into the pleural cavity to break the septa, respectively. Hydrodissection and guidewire-dissection might be minimally invasive alternatives for the treatment of septated empyema.

Belly dancer syndrome improved by withdrawal of droxidopa and amantadine.

A man hospitalized for cerebral infarction developed drug-induced belly dancer syndrome, which improved after withdrawal of droxidopa and amantadine. Drugs that modulate dopamine neurotransmission have been reported to be associated with this syndrome. When belly dancer syndrome is suspected, clinicians should consider drug-induced abdominal dyskinesia and medication withdrawal.

Two Cases of Perihepatitis With the Liver Capsule Irritation Sign: A New Physical Examination Technique.

Perihepatitis, including Fitz-Hugh-Curtis syndrome, is an uncommon, chronic manifestation of pelvic inflammatory disease usually affecting premenopausal women. It causes right upper quadrant pain due to inflammation of the liver capsule and adhesion of the peritoneum. Since delayed diagnosis of Fitz-Hugh-Curtis syndrome can lead to infertility and other complications, physical examination findings need to be investigated to predict perihepatitis in the early stages of the disease. Here, we hypothesized that perihepatitis is characterized by increased tenderness and spontaneous pain in the right upper abdomen when the patient is placed in the left lateral recumbent position (we termed this indication the "liver capsule irritation sign"). We examined the patients physically for the presence of this liver capsule irritation sign for an early diagnosis of perihepatitis. We report the first two cases of perihepatitis due to Fitz-Hugh-Curtis syndrome in which the liver capsule irritation sign observed during the physical examination was used for diagnosis. The liver capsule irritation sign is caused by two mechanisms: first, the liver falls gravitationally into the left lateral recumbent position, which makes the liver easier to palpate; and second, the peritoneum is stretched and thus stimulated. The second mechanism is that the transverse colon running around the right upper abdomen slumps gravitationally when the patient is in the left lateral recumbent position, allowing for direct palpation of the liver. The liver capsule irritation sign can be a useful physical finding, suggestive of perihepatitis due to Fitz-Hugh-Curtis syndrome. It may also be suitable in cases of perihepatitis caused by factors other than Fitz-Hugh-Curtis syndrome.

Ureterosciatic hernia with gluteal abscess: A case report.

A woman in her 90's developed pain in the left buttock, along with a left buttock mass. Contrast-enhanced computed tomography revealed a mass in the left gluteus muscle, ureteral dilation, and pelvic ureteral disconnection. Retrograde urography revealed bending of the left ureter at the sciatic foramen. The patient was diagnosed with a ureterosciatic hernia and gluteal abscess and treated with ureteral stent placement and antibiotics. The patient experienced no recurrence during the follow-up period. The gluteal abscess was probably caused by urinary leakage due to ureteral obstruction, because the abscess and urine culture results were consistent.

The Relationship of Patient Characteristics and Prolonged Pain after Treatment of Carpometacarpal Joint Arthritis of the Thumb.

Background: The carpometacarpal (CMC) joint of the thumb is the second most common site of osteoarthritis in the hand. Clinical severity stage of CMC joint arthritis has not been correlated with the pain level of the patient. Recently, the association of joint pain with patient psychological factor, such as depression or case-specific personality, has been investigated. This study was designed to determine the impact of psychological factors to residual pain after treatment of CMC joint arthritis, using pain catastrophizing scale (PCS) and the Yatabe-Guilford (YG) personality test. Methods: Twenty-six patients (7 males and 19 females) with 26 hands were included. Thirteen patients classified as Eaton stage 3 underwent suspension arthroplasty and 13 patients as Eaton stage 2 underwent conservative treatment using a custom fitted orthosis. Clinical evaluation was assessed using Visual Analogue Scale (VAS) and the quick Disabilities of the Arm, Shoulder and Hand Questionnaire Score (QuickDASH) at initial evaluation, at 1 month and at 3 months after treatment. We compared both groups using the PCS and YG test. Results: The PCS showed significant difference in the VAS scores only at initial evaluation in both surgical and conservative treatment. There was a significant difference in VAS at 3 months between the two groups in both surgical and conservative treatment and in QuickDASH at 3 months in conservative treatment. Conclusions: The YG test has been used mainly in psychiatry. Although this test has not yet been used worldwide, its usefulness has been recognised and applied clinically, especially in Asia. Patient characteristics are strongly associated with residual pain of the CMC joint arthritis of the thumb. The YG test is a useful tool to analyse pain-related patient characteristics and can be utilised to determine the therapeutic modalities and most effective rehabilitation programme for pain control. Level of Evidence: Level III (Therapeutic).

MYC/Glutamine Dependency Is a Therapeutic Vulnerability in Pancreatic Cancer with Deoxycytidine Kinase Inactivation-Induced Gemcitabine Resistance.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most life-threatening malignancies. Although the deoxycytidine analog gemcitabine has been used as the first-line treatment for PDAC, the primary clinical challenge arises because of an eventual acquisition of resistance. Therefore, it is crucial to elucidate the mechanisms underlying gemcitabine resistance to improve treatment efficacy. To investigate potential genes whose inactivation confers gemcitabine resistance, we performed CRISPR knockout (KO) library screening. We found that deoxycytidine kinase (DCK) deficiency is the primary mechanism of gemcitabine resistance, and the inactivation of CRYBA2, DMBX1, CROT, and CD36 slightly conferred gemcitabine resistance. In particular, gene expression analysis revealed that DCK KO cells displayed a significant enrichment of genes associated with MYC targets, folate/one-carbon metabolism and glutamine metabolism pathways. Evidently, chemically targeting each of these pathways significantly reduced the survival of DCK KO cells. Moreover, the pathways enriched in DCK KO cells represented a trend similar to those in PDAC cell lines and samples of patients with PDAC with low DCK expression. We further observed that short-term treatment of parental CFPAC-1 cells with gemcitabine induces the expression of several genes, which promote synthesis and transport of glutamine in a dose-dependent manner, which suggests glutamine availability as a potential mechanism of escaping drug toxicity in an initial response for survival. Thus, our findings provide insights into novel therapeutic approaches for gemcitabine-resistant PDAC and emphasize the involvement of glutamine metabolism in drug-tolerant persister cells. IMPLICATIONS: Our study revealed the key pathways involved in gemcitabine resistance in PDAC, thus providing potential therapeutic strategies.

[A Case of Resection of Locally Advanced Ascending Colon Cancer in an Elderly Patient with Parkinson's Disease].

The case presented here is of a man in his 80s who was attending the Department of Neurology for Parkinson's disease. He had a fever and visited the emergency department. A CT scan revealed a 10 cm mass in the hepatic flexure that was suspected of invading the duodenum, as well as numerous enlarged lymph nodes around the mass. A colonoscopy revealed a semi-peripheral type 3 tumor, and a biopsy showed adenocarcinoma(tub1-tub2). A right hemicolectomy was performed, and the tumor was located in the hepatic flexure of the ascending colon and was found to be in a mass with lymph nodes and adhesions to the duodenum. Due to the invasiveness of the surgery and the decrease in ADL, the patient's postoperative course required prolonged hospitalization. He was transferred to the hospital at POD33 and discharged at POD64. Due to his old age, adjuvant chemotherapy was not administered, and he is still alive 1 year after surgery with no recurrence. Even though his hospital stay was prolonged due to his decreased ADL, he is now able to return home. Aggressive resection may provide good results even in elderly patients.