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Dental cone beam computed tomography (CBCT) is a diverse 3D X-ray imaging technique that has enabled clear visualization of the teeth and surrounding structures. The most common diagnostic purpose of dental CBCT examination in children is ectopic eruption and impacted teeth, and a small field of view (FOV) is often used. Since it is difficult for children to control their body movements, reducing the rotation angle is effective. However, no studies have examined the effects of different rotation angles on radiation doses to highly radiosensitive organs in children using small FOVs. The purpose of this study was to examine the effects of small FOVs (4 × 4 cm and 6 × 6 cm) and rotation angles (360° and 180°) on doses that highly sensitize organs in children using dental CBCT. The entrance surface doses to lenses, thyroid lobes, parotid glands, and sublingual glands of a pediatric whole-body phantom were measured. By reducing the FOV from 6 × 6 cm to 4 × 4 cm, the dose to the sublingual gland could be significantly decreased. Additionally, by reducing the rotation angle from 360° to 180°, the lens dose can be decreased significantly. As the rate of dose reduction varies among organs, it is important to consider the relative positions of different organs with respect to the FOV and the trajectory of the X-ray tube.

Abstract Enhancements of edge zonal flows, radial electric fields, and turbulence are observed in electron cyclotron resonance heating-heated plasmas (Zhao et al 2013 Nucl. Fusion 53 083011). In this paper, the effects of sawtooth heat pulses on flows and turbulence are presented. These experiments are performed using multiple Langmuir probe arrays in the edge plasmas of the HL-2A tokamak. The edge zonal flows, radial electric fields, and turbulence are all enhanced by sawteeth. Propagation of the zonal flow and turbulence intensities is also observed. The delay time of the maximal intensity of the electric fields, zonal flows, and turbulence with respect to the sawtooth crashes is estimated as ∼1 ms and comparable to that of the sawtooth-triggered intermediate phases. Not only the zonal flows but also the radial electric fields lag behind the turbulence. Furthermore, the intensities of both the zonal flows and electric fields nearly linearly increase/decrease with the increase/decrease of the turbulence intensity. A double-source predator–prey model analysis suggests that a relatively strong turbulence source may contribute to the dominant zonal flow formation during sawtooth cycles.

We examined whether U46619 (a prostanoid TP receptor agonist) could enhance the contractions of guinea pig urinary bladder smooth muscle (UBSM) in response to acetylcholine (ACh) and an ATP analog (α,β-methylene ATP (αβ-MeATP)) through stimulation of the UBSM TP receptor and whether protein kinase C (PKC) is involved. U46619 (10−7 M) markedly enhanced UBSM contractions induced by electrical field stimulation and ACh/αβ-MeATP (3 × 10−6 M each), the potentiation of which was completely suppressed by SQ 29,548 (a TP receptor antagonist, 6 × 10−7 M). PKC inhibitors did not attenuate the ACh-induced contractions enhanced by U46619 although they partly suppressed the U46619-enhanced, αβ-MeATP-induced contractions. While phorbol 12-myristate 13-acetate (PMA, a PKC activator, 10−6 M) did not enhance ACh-induced contractions, it enhanced αβ-MeATP-induced contractions, an effect that was completely suppressed by PKC inhibitors. αβ-MeATP-induced contractions, both with and without U46619 enhancement, were strongly inhibited by diltiazem. U46619/PMA enhanced 50 mM KCl-induced contractions, the potentiation of which was partly/completely attenuated by PKC inhibitors. These findings suggest that U46619 potentiates parasympathetic nerve-associated UBSM contractions by stimulating UBSM TP receptors. PKC-increased Ca2+ influx through voltage-dependent Ca2+ channels may partially play a role in purinergic receptor-mediated UBSM contractions enhanced by TP receptor stimulation.

Introduction The performance of robot‐assisted laparoscopic pyeloplasty has recently been increasing in frequency. However, patients with duplicated renal pelvises and ureters can present challenges. Case presentation A 71‐year‐old woman presented with flank pain and was diagnosed with ureteropelvic junction obstruction with an incomplete duplicated collecting system. Preoperative imaging did not reveal the details of the stenosis. Therefore, three reconstructive procedures were prepared: The Anderson–Hynes procedure, end‐to‐side pyeloureterostomy, and upper pole ureter to lower pole pyeloplasty with the Anderson–Hynes procedure for the lower pole. These procedures were determined by the length of the intact ureter and the presence of crossed vessels. During the surgery, the crossing vein was severed, allowing successful reconstruction with Anderson–Hynes anastomosis. Conclusion Preoperative evaluation and preparation of multiple surgical techniques are crucial in robot‐assisted laparoscopic pyeloplasty for incomplete duplicated collecting systems.

Abstract Brain metastases develop in 0.5–0.7% of patients with gastric/gastroesophageal junction (G/GEJ) cancer. Although rare, brain metastasis is often identified when the patient is already symptomatic; hence prognosis is poor. Given the therapeutic developments for G/GEJ cancer, overall survival is prolonged, thereby the incidence of brain metastases is predicted to increase. We retrospectively surveyed the rate of brain metastasis among 1257 patients diagnosed with G/GEJ cancer who received chemotherapy between January 2011 and April 2021. We investigated the time of onset of brain metastasis, treatments administered, and impact of the metastasis on the overall treatment course and prognosis. Of the 741 patients included in the analysis, brain metastasis was confirmed in 16 (2.2%). The median survival time (MST) from G/GEJ cancer diagnosis was 14.9 months in patients with brain metastasis detected during the treatment period, and the MST from the diagnosis of brain metastasis was 2.8 months. Patients who received chemotherapy exhibited prolonged survival compared with those who did not (12.4 months vs 1.0 months, p

Abstract Background Patients with familial adenomatous polyposis (FAP) have a lifetime risk of developing duodenal adenomas approaching 100%, and the relative risk for duodenal cancer compared with the general population is high. We conducted a retrospective study to investigate the progression of non-ampullary duodenal adenomas (NADAs) and risk factors for advanced lesions in patients with FAP. Methods Of 248 patients with 139 pedigrees at 2 institutes, we assessed 151 patients with 100 pedigrees with a pathogenic germline variant in the adenomatous polyposis coli gene, excluding mosaic variants. We evaluated the prevalence of NADAs in patients with FAP, the progression of these adenomas to advanced adenoma during the observation period, and the risk factors for the lifetime development of high-grade dysplasia (HGD), large (≥ 10 mm) duodenal adenomas, and Spiegelman stage IV. Results During the median observation period of 7 years, the incidences of patients with NADAs, with more than 20 polyps, with polyps ≥ 10 mm, with HGD, and with stage IV at the last esophagogastroduodenoscopy were increased 1.6-fold, 1.7-fold, 5-fold, 22-fold, and 9-fold, respectively. Intramucosal cancer occurred in three patients (2%), but no patients developed invasive cancer during the observation period because we performed endoscopic intervention for advanced adenomas. Stage progression was observed in 71% of 113 patients. Stage IV was more common in women, patients with a history of colectomy, and those with a 3’ side mutation in their adenomatous polyposis coli gene. Conclusions NADAs in patients with FAP frequently become exacerbated. Our findings suggest that patients with FAP who develop duodenal adenomas should be surveyed to prevent the development of duodenal cancer.

Abstract Background Hypertension is the most frequently occurring adverse event of lenvatinib, recognized relatively early in its course. However, the trend in blood pressure after the initiation of lenvatinib and the outcomes with antihypertensive treatment are unclear. This study aimed to clarify the association between baseline blood pressure and the incidence of lenvatinib‐induced hypertension in patients with thyroid cancer. Methods This retrospective study included 65 patients without hypertension at the time of lenvatinib initiation. Patients were divided into two groups: those who developed hypertension grade ≥3 (HTN group) and those who did not develop hypertension grade ≥3 (non‐HTN group). Results Of the 65 patients, 46 (71%) developed hypertension grade ≥3. In both HTN and non‐HTN groups, blood pressure significantly increased the day after lenvatinib initiation. There was no significant difference in the elevated values of both the changes in systolic blood pressure (ΔSBP) and diastolic blood pressure (ΔDBP) between the two groups, with an average increase of 20 mmHg in SBP and 13 mmHg in DBP from baseline. The median (range) time to the onset of hypertension grade ≥3 was 2 days (1–12 days). In the multivariable analysis, patients with normal (SBP 120–129 mmHg and/or DBP 80–84 mmHg) or high‐normal baseline blood pressure (SBP 130–139 mmHg and/or DBP 85–89 mmHg) were at higher risk of developing hypertension grade ≥3 than those with optimal baseline blood pressure (SBP

C18H20N6·2(CH3OH), triclinic, P1‾$P\overline{1}$ (no. 2), a = 5.0063(2) Å, b = 8.5627(5) Å, c = 12.8216(6) Å, α = 77.898(4)°, β = 89.301(4)°, γ = 76.601(4)°, V = 522.40(5) Å3, Z = 1, Rgt(F) = 0.0577, wRref(F2) = 0.1642, T = 178 K.

2[C5H10N3][C8F4O4], monoclinic, P21/n (no. 14), a = 6.1490(2) Å, b = 11.0063(3) Å, c = 14.0214(3) Å, β = 94.386(5)∘, V = 946.16(5) Å3, Z = 2, Rgt(F) = 0.0371, wRref(F2) = 0.1127, T = 178 K.

C26H36N6, triclinic, P1‾$\overline{1}$ (no. 2), a = 5.7137(2) Å, b = 10.4374(3) Å, c = 11.1141(3) Å, α = 104.980(3)°, β = 94.279(3)°, γ = 93.876(3)°, V = 635.89(3) Å3, Z = 1, Rgt(F) = 0.0503, wRref(F2) = 0.1220, T = 178 K.

ABSTRACT: Yogurt is made by fermenting milk with 2 lactic acid bacteria, Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus. To comprehensively understand the protocooperation mechanism between S. thermophilus and L. bulgaricus in yogurt fermentation, we examined 24 combinations of cocultures comprising 7 fast- or slow-acidifying S. thermophilus strains with 6 fast- or slow-acidifying L. bulgaricus strains. Furthermore, 3 NADH oxidase (Nox)-deficient mutants (Δnox) and one pyruvate formate-lyase deficient mutant (ΔpflB) of S. thermophilus were used to evaluate the factor that determines the acidification rate of S. thermophilus. The results revealed that the acidification rate of S. thermophilus monoculture determined the yogurt fermentation rates, despite the coexistence of L. bulgaricus, whose acidification rate was either fast or slow. Significant correlation was found between the acidification rate of S. thermophilus monoculture and the amount of formate production. Result using ΔpflB showed that the formate was indispensable for the acidification of S. thermophilus. Moreover, results of the Δnox experiments revealed that formate production required Nox activity, which not only regulated dissolved oxygen, but also the redox potential. The Nox provided the large decrease in redox potential required by pyruvate formate-lyase to produce formate. A highly significant correlation was found between formate accumulation and Nox activity in S. thermophilus. In conclusion, the formate production ability provided by the action of Nox activity determines the acidification rate of S. thermophilus, and consequently, regulates yogurt coculture fermentation.

Abstract The common marmoset (Callithrix jacchus) has attracted attention as a valuable primate model for the analysis of human diseases. Despite the potential for primate genetic modification, however, its widespread lab usage has been limited due to the requirement for a large number of eggs. To make up for traditional oocyte retrieval methods such as hormone administration and surgical techniques, we carried out an alternative approach by utilizing ovarian tissue from deceased marmosets that had been disposed of. This ovarian tissue contains oocytes and can be used as a valuable source of follicles and oocytes. In this approach, the ovarian tissue sections were transplanted under the renal capsules of immunodeficient mice first. Subsequent steps consist of development of follicles by hormone administrations, induction of oocyte maturation and fertilization, and culture of the embryo. This method was first established with rat ovaries, then applied to marmoset ovaries, ultimately resulting in the successful acquisition of the late-stage marmoset embryos. This approach has the potential to contribute to advancements in genetic modification research and disease modeling through the use of primate models, promoting biotechnology with non-human primates and the 3Rs principle in animal experimentation.

Abstract Several studies conducted in patients with various stages of chronic kidney disease (CKD) have investigated the association of iron status markers, such as transferrin saturation (TSAT) and serum ferritin, with kidney outcomes. However, the associations were inconsistent and remain strongly debated. Therefore, we aimed to investigate whether TSAT and serum ferritin levels were associated with kidney outcome in such a population. In this study, 890 patients who were admitted for the evaluation of and education for CKD were prospectively followed. Primary kidney outcome was a composite of doubling of serum creatinine, end-stage kidney disease, or death due to kidney failure. Participants were divided into quartiles (Q1–Q4) according to TSAT or serum ferritin levels. During a median follow-up period of 2.8 years, kidney events occurred in 358 patients. In the multivariable Cox analyses, compared with Q3 of TSAT, the hazard ratios (95% confidence intervals) for Q1, Q2, and Q4 were 1.20 (0.87, 1.66), 1.38 (1.01, 1.87), and 1.14 (0.82, 1.59), respectively. Compared with Q2 of serum ferritin, lower and higher quartiles had a significantly increased risk for kidney outcome; hazard ratios (95% confidence intervals) for Q1, Q3, and Q4 were 1.64 (1.18, 2.27), 1.71 (1.24, 2.37), and 1.52 (1.10, 2.10), respectively. A Fine-Gray model with death before kidney events as a competing risk showed results similar to the above. In CKD, lower and higher ferritin levels were independent risk factors for kidney disease progression.

Abstract Background Foreign body-induced acute appendicitis is rare but could most often be caused by fish bones; those caused by endoscopic clips are highly rare. Herein, we report a case of acute appendicitis caused by endoscopic clips that developed 2 years after the endoscopic procedure. Case presentation A 68-year-old man with a 2-year history of hemodialysis (HD) for diabetic nephropathy visited our hospital with pain in the right lower quadrant. He had undergone endoscopic submucosal dissection (ESD) for gastric adenoma 2 years earlier. Abdominal computed tomography revealed acute gangrenous appendicitis and a high-density structure lodged in the appendix. This structure was determined to be an endoscopic clip that was lodged in the patient’s appendix for 2 years. The patient underwent an emergency laparoscopic appendectomy, and an endoscopic clip covered by a fecalith was found in the appendix. Conclusion Endoscopic clips usually fall off spontaneously in approximately a week and pass through stool. However, in this case, appendicitis developed 2 years after the ESD. An emergency surgical appendectomy may be recommended for appendicitis caused by foreign bodies. Prophylactic appendectomy or removal of foreign bodies should be considered for HD patients, even in the absence of symptoms owing to the potential severity of appendicitis in such patients.

Abstract Background Patients with unresectable pancreatic cancer (PC) sometimes experience gastrointestinal bleeding (GIB) due to tumor invasion of the gastrointestinal tract (tumor bleeding); no standard treatment has been established yet for this complication. Palliative radiotherapy (PRT) could be promising, however, there are few reports of PRT for tumor bleeding in patients with unresectable PC. Therefore, we evaluated the outcomes of PRT for tumor bleeding in patients with unresectable PC. Methods We reviewed the medical records of patients with unresectable PC diagnosed at our institution between May 2013 and January 2022, and identified patients with endoscopically confirmed tumor bleeding who had received PRT. PRT was administered at a total dose of 30 Grays (Gy) in 10 fractions, 20 Gy in 5 fractions, or 8 Gy in a single fraction, and the dose selection was left to the discretion of the attending radiation oncologists. Results During the study period, 2562 patients were diagnosed as having unresectable PC at our hospital, of which 225 (8.8%) developed GIB. Among the 225 patients, 63 (2.5%) were diagnosed as having tumor bleeding and 20 (0.8%) received PRT. Hemostasis was achieved in 14 of the 20 patients (70%) who received PRT, and none of these patients developed grade 3 or more adverse events related to the PRT. The median time to hemostasis was 8.5 days (range 7–14 days). The rebleeding rate was 21.4% (3/14). The median hemoglobin level increased significantly (p

ABSTRACT Aims/Introduction Glucagon is secreted from pancreatic α‐cells and plays an important role in amino acid metabolism in liver. Various animal models deficient in glucagon action show hyper‐amino acidemia and α‐cell hyperplasia, indicating that glucagon contributes to feedback regulation between the liver and the α‐cells. In addition, both insulin and various amino acids, including branched‐chain amino acids and alanine, participate in protein synthesis in skeletal muscle. However, the effect of hyperaminoacidemia on skeletal muscle has not been investigated. In the present study, we examined the effect of blockade of glucagon action on skeletal muscle using mice deficient in proglucagon‐derived peptides (GCGKO mice). Materials and Methods Muscles isolated from GCGKO and control mice were analyzed for their morphology, gene expression and metabolites. Results GCGKO mice showed muscle fiber hypertrophy, and a decreased ratio of type IIA and an increased ratio of type IIB fibers in the tibialis anterior. The expression levels of myosin heavy chain (Myh) 7, 2, 1 and myoglobin messenger ribonucleic acid were significantly lower in GCGKO mice than those in control mice in the tibialis anterior. GCGKO mice showed a significantly higher concentration of arginine, asparagine, serine and threonine in the quadriceps femoris muscles, and also alanine, aspartic acid, cysteine, glutamine, glycine and lysine, as well as four amino acids in gastrocnemius muscles. Conclusions These results show that hyperaminoacidemia induced by blockade of glucagon action in mice increases skeletal muscle weight and stimulates slow‐to‐fast transition in type II fibers of skeletal muscle, mimicking the phenotype of a high‐protein diet.

Background/Aims Mechanical properties (MPs) and axial and radial force (AF and RF) may influence the efficacy and complications of self-expandable metallic stent (SEMS) placement. We measured the MPs of various SEMSs and examined their influence on the SEMS clinical ability. Methods We evaluated the MPs of 29 types of 10-mm SEMSs. RF was measured using a conventional measurement device. AF was measured using the conventional and new methods, and the correlation between the methods was evaluated. Results A high correlation in AFs was observed, as measured by the new and conventional manual methods. AF and RF scatterplots divided the SEMSs into three subgroups according to structure: hook-and-cross-type (low AF and RF), cross-type (high AF and low RF), and laser-cut-type (intermediate AF and high RF). The hook-and-cross-type had the largest axial force zero border (>20°), followed by the laser-cut and cross types. Conclusions MPs were related to stent structure. Hook-and-cross-type SEMSs had a low AF and high axial force zero border and were considered safest because they caused minimal stress on the biliary wall. However, the increase in RF must be overcome.

Abstract Background Anti‐PD‐1‐based immunotherapy is considered a preferred first‐line treatment for advanced BRAF V600‐mutant melanoma. However, a recent international multi‐center study suggested that the efficacy of immunotherapy is poorer in Asian patients in the non‐acral cutaneous subtype. We hypothesized that the optimal first‐line treatment for Asian patients may be different. Methods We retrospectively collected data of Asian patients with advanced BRAF V600‐mutant melanoma treated with first‐line BRAF/MEK inhibitors (BRAF/MEKi), anti‐PD‐1 monotherapy (Anti‐PD‐1), and nivolumab plus ipilimumab (PD‐1/CTLA‐4) between 2016 and 2021 from 28 institutions in Japan. Results We identified 336 patients treated with BRAF/MEKi (n = 236), Anti‐PD‐1 (n = 64) and PD‐1/CTLA‐4 (n = 36). The median follow‐up duration was 19.9 months for all patients and 28.6 months for the 184 pa tients who were alive at their last follow‐up. For patients treated with BRAF/MEKi, anti‐PD‐1, PD‐1/CTLA‐4, the median ages at baseline were 62, 62, and 53 years (p = 0.03); objective response rates were 69%, 27%, and 28% (p

Abstract Background The role of endocrine therapy in the treatment of patients in a postmenopausal hormonal state and with estrogen receptor (ER)‐positive, human epidermal growth factor receptor 2 (HER2)‐positive advanced or metastatic breast cancer (AMBC) is unclear. Methods We analyzed the data from 94 patients with ER‐positive HER2‐positive AMBC enrolled in the Safari study (UMIN000015168), a retrospective cohort study of 1072 ER‐positive AMBC patients in a postmenopausal hormonal state who received fulvestrant 500 mg (F500): (1) to compare time to treatment failure (TTF) and overall survival (OS) by treatment group, and TTF by treatment line; (2) in patients who received endocrine therapy (including F500) or anti‐HER2 therapy as initial systemic therapy before chemotherapy, to investigate relations between TTF for the first‐line therapy or time to chemotherapy (TTC) and OS; (3) to investigate factors associated with OS. Results The TTF was longer in the patients treated with F500 as first‐ or second‐line therapy (n = 20) than in those who received later‐line F500 therapy (n = 74) (6.6 vs. 3.7 months; HR, 1.98; p = 0.014). In the 59 patients who received endocrine therapy or anti‐HER2 therapy as initial systemic therapy before chemotherapy, those with TTC ≥3 years had longer median OS than those with TTC

BackgroundOlfactory neuroblastoma (ONB) is a rare malignant tumor of the head and neck. Due to its rarity, standard systemic therapy for this condition has yet to be established. In particular, the use of immune checkpoint inhibitors (ICIs) for the recurrent or metastatic (R/M) ONB population remains unclear.MethodsWe retrospectively evaluated 11 patients with R/M ONB who received any systemic chemotherapy at two Japanese institutions (National Cancer Center Hospital East and Kyushu Medical Center) between January 2002 and March 2022 and analyzed outcomes by use of anti-PD-1 antibody (nivolumab or pembrolizumab) monotherapy.ResultsOf the 11 patients, 6 received ICI (ICI-containing treatment group) and the remaining 5 were treated with systemic therapy but not including ICI (ICI-non-containing treatment group). Overall survival (OS) was significantly longer in the ICI-containing group (median OS: not reached vs. 6.4 months, log-rank p-value: 0.035). The fraction of ICI systemic therapy in the entire treatment period of this group reached 85.9%. Four patients (66.7%) in the ICI-containing treatment group experienced immune-related adverse events (irAE), with grades of 1/2. No irAE of grade 3 or more was seen, and no patient required interruption or discontinuation of treatment due to toxicity.ConclusionICI monotherapy appears to be effective and to contribute to prolonged survival in R/M ONB.

Abstract Background/Aims The sensitivities of endoscopic trans‐papillary pathologic diagnosis of biliary tract cancer (BTC) are unsatisfactory. Recently, the diagnostic utility of the endoscopic scraper device, Trefle for biliary stricture has been reported. The Trefle can be guided to the target biliary stricture over the guidewire and is as easy to use as the conventional brush catheter (CBC). This study evaluated the efficacy and safety of Trefle‐assisted tissue acquisition combined cell block method and CBC cytology for biliary strictures due to BTCs. Methods We retrospectively reviewed consecutive patients with biliary strictures in whom CBC cytology or Trefle‐assisted tissue acquisition under endoscopic retrograde cholangiopancreatography was performed for suspected BTCs from January 2015 to June 2022 at our institution. Results 173 patients (CBC group; n = 55, Trefle group; n = 118) were enrolled in this study. The sensitivity, specificity, and accuracy of CBC cytology for BTC were 68.3%/100%/76.4%. On the other hand, the sensitivity, specificity, and accuracy of Trefle‐assisted tissue acquisition for BTC were 93.7%/95.7%/94.1%, showing superior sensitivity (p < 0.001) and accuracy (p = 0.002) compared to that of CBC. Conclusions Compared to CBC cytology, Trefle‐assisted tissue acquisition has superior diagnostic performance while maintaining procedural simplicity and is considered useful for diagnosing malignant biliary stricture.

ABSTRACT Purpose: To develop a new 4/6 infarct nephrectomy (INx) model rat mimicking moderate chronic kidney disease (CKD) and to evaluate its application. Methods: We modified the conventional 5/6 INx rat model to create the 4/6 INx model by ligating the renal artery branch to induce infarction of one-third of the left kidney after right kidney removal and compared biochemically and histologically both models. To demonstrate the application of the 4/6 INx model, the effects of a supplementary compound containing calcium carbonate, chitosan, palm shell activated charcoal etc., that is effective for both CKD and its complications, were compared between both models. Results: Impairment of renal function in the 4/6 INx group was significantly more moderate than in the 5/6 INx group (P < 0.05). The 4/6 INx group showed less histological damage in kidney than in the 5/6 INx group. The supplementary compound did not improve CKD in the 5/6 INx group, but ameliorated elevation of blood urea nitrogen in the 4/6 INx group. Conclusions: We developed the 4/6 INx model, which is more moderate than the conventional 5/6 INx model. This model could potentially demonstrate the effectiveness of drugs and supplements intended to prevent CKD and its progression.

Although the midbrain dopamine (DA) system plays a crucial role in higher cognitive functions, including updating and maintaining short-term memory, the encoding properties of the somatic spiking activity of ventral tegmental area (VTA) DA neurons for short-term memory computations have not yet been identified. Here, we probed and analyzed the activity of optogenetically identified DA and GABA neurons while mice engaged in short-term memory-dependent behavior in a T-maze task. Single-neuron analysis revealed that significant subpopulations of DA and GABA neurons responded differently between left and right trials in the memory delay. With a series of control behavioral tasks and regression analysis tools, we show that firing rate differences are linked to short-term memory-dependent decisions and cannot be explained by reward-related processes, motivated behavior, or motor-related activities. This evidence provides novel insights into the mnemonic encoding activities of midbrain DA and GABA neurons.