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Capnocytophaga canimorsus (CP) causes severe infections in immunocompromised individuals. Three serovars (A, B, and C) are known to be responsible for more than 90% of infections associated with dog bites, although these three constitute only 8% of the serovars carried by dogs. We experienced a post-splenectomy non-severe case of CP withserovar type E, which has never been isolated in Japan. The prognosis of type E CP infections may be better than that of types A, B, and C infections because of the disproportion of serovars between clinical human isolates and dog oral isolates.
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Complications of neurofibromatosis type 1 include fatal bleeding events due to vascular fragility. In this case of hemorrhagic shock due to a neurofibroma, the bleeding was controlled using an occlusion balloon and endovascular treatment which stabilized the patient. Systemic vascular investigation for bleeding sites is important to prevent fatal outcomes.
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BACKGROUND: Although Chlamydophila pneumoniae (CP)is known to play a role in atherosclerosis and endothelial injury, its past infection on the mortality of coronavirus disease 2019 (COVID-19), which was also reported to be a vascular disease, remains unknown. METHODS: In this retrospective cohort study, we examined 78 COVID-19 patients and 32 bacterial pneumonia patients who visited a tertiary emergency center in Japan between April 1, 2021, and April 30, 2022. CP antibody levels, including IgM, IgG, and IgA, were measured. RESULTS: Among all patients, the CP IgA-positive rate was significantly associated with age (P = 0.002). Between the COVID-19 and non-COVID-19 groups, no difference in the positive rate for both CP IgG and IgA was observed (P = 1.00 and 0.51, respectively). The mean age and proportion of males were significantly higher in the IgA-positive group than in the IgA-negative group (60.7 vs. 75.5, P = 0.001; 61.5% vs. 85.0%, P = 0.019, respectively). Smoking and dead outcomes were significantly higher both in the IgA-positive group and IgG-positive group (smoking: 26.7% vs. 62.2, P = 0.003; 34.7% vs. 73.1%, P = 0.002, dead outcome: 6.5% vs. 29.8%, P = 0.020; 13.5% vs. 34.6%, P = 0.039, respectively). Although the log-rank test revealed higher 30-day mortality in the IgG-positive group compared to the IgG-negative group (P = 0.032), Cox regression analysis demonstrated no significant difference between the IgG-positive and negative groups (hazard ratio (HR) = 4.10, 95%CI = 0.94-18.0, P = 0.061). CONCLUSION: The effect of past CP infection on 30-day mortality in COVID-19 patients was not obvious.
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Aim: Coronavirus disease 2019 pneumonia differs from ordinary pneumonia in that it is associated with lesions that reduce pulmonary perfusion. Dual-energy computed tomography is well suited to elucidate the etiology of coronavirus disease 2019 pneumonia, because it highlights changes in organ blood flow. In this study, we investigated whether dual-energy computed tomography could be used to determine the severity of coronavirus disease 2019 pneumonia. Methods: Patients who were diagnosed with coronavirus disease 2019 pneumonia, admitted to our hospital, and underwent dual-energy computed tomography were included in this study. Dual-energy computed tomography findings, plane computed tomography findings, disease severity, laboratory data, and clinical features were compared between two groups: a critical group (18 patients) and a non-critical group (30 patients). Results: The dual-energy computed tomography results indicated that the percentage of flow loss was significantly higher in the critical group compared with the non-critical group (P < 0.001). Additionally, our data demonstrated that thrombotic risk was associated with differences in clinical characteristics (P = 0.018). Receiver operating characteristic analysis revealed that the percentage of flow loss, evaluated using dual-energy computed tomography, could predict severity in the critical group with 100% sensitivity and 77% specificity. However, there were no significant differences in the receiver operating characteristic values for dual-energy computed tomography and plane computed tomography. Conclusion: Dual-energy computed tomography can be used to associate the severity of coronavirus disease 2019 pneumonia with high accuracy. Further studies are needed to draw definitive conclusions.
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ß-Carotene is an essential nutrient in cattle reproduction. The objective of this study was to evaluate the effect of ß-carotene supplementation on ovarian activities throughout the estrous cycle in nonpregnant Japanese Black cows. The estrous cycles of eight nonpregnant Japanese Black cows were synchronized using a double synch protocol, and the cows were divided into two groups. The cows in the ß-carotene (BC) group received supplementation with 1000 mg/day ß-carotene for 46 days including the synchronization period. The cows in the control (C) group did not receive ß-carotene supplementation. The results showed that ß-carotene supplementation at 1000 mg/day was sufficient to maintain a high plasma ß-carotene concentration and increase the plasma retinol concentration and that ß-carotene supplementation had no significant effects on the dominant follicle diameter, total number of estrus behaviors, or length of the estrous cycle. In contrast, the areas under the P4 concentration curves in the BC group were higher than those obtained for the C group. In conclusion, a high plasma ß-carotene concentration in Japanese Black cows promotes P4 production in the luteal phase of the estrous cycle and total P4 production throughout the estrous cycle without changing the length of the estrous cycle.
Subject(s)
Progesterone , beta Carotene , Female , Cattle , Animals , beta Carotene/pharmacology , Estrous Cycle , Ovarian Follicle , Estrus , Estrus Synchronization/methodsABSTRACT
Background: Acute pancreatitis triggered by causative agents, including alcohol consumption, gallstones, dyslipidemia, drugs, and infection, is frequently addressed. However, reports of acute pancreatitis caused by duodenal bezoars are limited. Case Presentation: A 75-year-old man experiencing abdominal pain and frequent vomiting was transferred to our hospital. His medical records presented history of diabetes, hypertension, dyslipidemia, and gastric cancer surgery. Computed tomography of the abdomen indicated duodenal dilatation, enlarged pancreas, and fluid retention, with no bile duct stones present. Minor bleeding and duodenal bezoar were endoscopically detected with esophagogastroduodenoscopy (EGD). He was diagnosed with severe acute pancreatitis caused by a bezoar and admitted to the intensive care unit. The duodenal bezoar was dissected and removed with three repetitions of EGD, and the patient was discharged without any complications. Conclusion: Herein, we report a case showing that endoscopic procedures could be effective treatment options in severe pancreatitis caused by duodenal bezoars.
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Mood disorders such as depression, anxiety, and bipolar disorder are highly associated with disrupted daily rhythms of activity, which are often observed in shift work and sleep disturbance in humans. Recent studies have proposed the REV-ERBα protein as a key circadian nuclear receptor that links behavioural rhythms to mood regulation. However, how the Rev-erbα gene participates in the regulation of mood remains poorly understood. Here, we show that the regulation of the serotonergic (5-HTergic) system, which plays a central role in stress-induced mood behaviours, is markedly disrupted in Rev-erbα-/- mice. Rev-erbα-/- mice exhibit both negative and positive behavioural phenotypes, including anxiety-like and mania-like behaviours, when subjected to a stressful environment. Importantly, Rev-erbα-/- mice show a significant decrease in the expression of a gene that encodes the rate-limiting enzyme of serotonin (5-HT) synthesis in the raphe nuclei (RN). In addition, 5-HT levels in Rev-erbα-/- mice are significantly reduced in the prefrontal cortex, which receives strong inputs from the RN and controls stress-related behaviours. Our findings indicate that Rev-erbα plays an important role in controlling the 5-HTergic system and thus regulates mood and behaviour.
Subject(s)
Circadian Clocks , Animals , Circadian Clocks/genetics , Circadian Rhythm/genetics , Humans , Mice , Mice, Knockout , Nuclear Receptor Subfamily 1, Group D, Member 1/genetics , Nuclear Receptor Subfamily 1, Group D, Member 1/metabolism , SerotoninABSTRACT
Aim: This study compared the clinical outcomes of critically ill patients with coronavirus disease (COVID-19) pneumonia treated with high-dose methylprednisolone and other steroids. Methods: This retrospective observational study included critically ill COVID-19 pneumonia adult patients with tracheal intubation treated between April 1, 2020, and September 15, 2021. Of the 46 patients who met the inclusion criteria, 36 received steroid pulse therapy (Group P) and 10 received steroids without pulse therapy (Group NP). Subgroup analyses in Group P by methylprednisolone dose of 1000 or 500 mg for 3 days during intensive care unit stay were carried out. The primary and secondary outcomes were 28-day mortality and steroid-associated complications, respectively. Results: In the Kaplan-Meier curve analysis, there was no difference in the 28-day survival between P and NP groups (log-rank P = 0.046). Univariate Cox proportional hazard model also showed that Group P had a decreased 28-day mortality (hazard ratio 0.30; [95% confidence interval, 0.20-0.44]; P < 0.01). After adjusting for covariates (age, sex, remdesivir, baricitinib, and favipiravir), using the multivariate Cox proportional hazards model, Group P had improved 28-day mortality (0.50 [0.30-0.85], P = 0.01). Conclusion: Steroid pulse therapy might improve the 28-day and in-hospital mortality in critically ill patients with COVID-19 pneumonia.
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Porphyromonas asaccharolytica rarely causes Lemierre's syndrome (LS), which is characterised by sepsis and thrombophlebitis of the internal jugular vein. An 18-year-old man presented with fever and a sore throat after sexual contact containing oral sex, and his blood sample was positive for atypical lymphocytes. Infectious mononucleosis was suspected initially. However, laboratory data showed elevated D-dimer and procalcitonin levels, and a computed tomography scan showed a thrombus in the internal jugular vein leading to the diagnosis of LS. The Mycoplasma pneumoniae (MP) IgM titre was 1:640 (normal, â¦1:40), and the Epstein-Barr nuclear antigen titre (taken 59 days after admission) was 1:10 (normal, <1:10). It was assumed that LS developed after infection with Epstein-Barr virus (EBV) and MP. LS should be suspected in young patients with fever and sore throat with a history of recent sexual contact. As pharyngitis was considered the cause of LS, evaluation of the preceding infection such as MP or EBV leading to pharyngitis should also be considered.
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Invasive pulmonary aspergillosis (IPA) has been reported to occur secondary to coronavirus disease 2019 (COVID-19), and the condition has been termed COVID-19-associated pulmonary aspergillosis (CAPA). We diagnosed two severe COVID-19 cases with multiple cavitary lung lesions and chronic pulmonary aspergillosis (CPA) on days 58 and 48 of admission, respectively, with gradual improvement in the respiratory status. Both patients were positive for Aspergillus-precipitating antibodies (APAb). We chose oral itraconazole (ITCZ) for both patients because of its convenience in terms of long-term treatment. Cavitary lesions diminished after ITCZ administration. The risk factors for pulmonary aspergillosis in both patients were determined to be steroid pulse therapy, use of baricitinib, diabetes mellitus (DM), ICU admission, long hospital stay, and the use of broad-spectrum antibiotics. Pulmonary aspergillosis must be suspected in patients with severe COVID-19, even if they are asymptomatic, because not only IPA but also CPA can occur following COVID-19. Therefore, oral ITCZ may be a treatment option for CPA following COVID-19.
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By combining video laryngoscopy and fiberoptic bronchoscopy, awake intubation can be performed more safely.
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BACKGROUND: Inferior vena cava thrombosis is a rare blunt abdominal trauma complication often associated with severe liver injury. We present two cases of inferior vena cava thrombosis due to mild liver injuries. CASE PRESENTATION: Case 1 was a 25-year-old woman taking oral contraceptives for dysmenorrhea who was injured in a motorcycle accident. Contrast-enhanced computed tomography revealed hepatic contusion of the sixth segment. At 1 week after the accident, inferior vena cava thrombosis was detected. Case 2 was a 58-year-old man injured in a motorcycle accident. Contrast-enhanced computed tomography showed traumatic subarachnoid hemorrhage, right hemothorax, and liver injury with hepatic contusion of the sixth segment. At 1 week after the accident, inferior vena cava thrombosis was observed. CONCLUSION: Inferior vena cava thrombosis can occur following liver injury, regardless of damage severity. When there are thrombogenic factors and damage near the inferior vena cava, follow-up examinations should be carried out.
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BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic rapidly increases the use of mechanical ventilation (MV). Such cases further require extracorporeal membrane oxygenation (ECMO) and have a high mortality. OBJECTIVE: We aimed to identify prognostic biomarkers pathophysiologically reflecting future deterioration of COVID-19. METHODS: Clinical, laboratory, and outcome data were collected from 102 patients with moderate to severe COVID-19. Interleukin (IL)-6 level and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA copy number in plasma were assessed with ELISA kit and quantitative PCR. RESULTS: Twelve patients died or required ECMO owing to acute respiratory distress syndrome despite the use of MV. Among various variables, a ratio of oxygen saturation to fraction of inspired oxygen (SpO2/FiO2), IL-6, and SARS-CoV-2 RNA on admission before intubation were strongly predictive of fatal outcomes after the MV use. Moreover, among these variables, combining SpO2/FiO2, IL-6, and SARS-CoV-2 RNA showed the highest accuracy (area under the curve: 0.934). In patients with low SpO2/FiO2 (< 261), fatal event-rate after the MV use at the 30-day was significantly higher in patients with high IL-6 (> 49 pg/mL) and SARS-CoV-2 RNAaemia (> 1.5 copies/µL) compared to those with high IL-6 or RNAaemia or without high IL-6 and RNAaemia (88% vs. 22% or 8%, log-rank test P = 0.0097 or P < 0.0001, respectively). CONCLUSIONS: Combining SpO2/FiO2 with high IL-6 and SARS-CoV-2 RNAaemia which reflect hyperinflammation and viral overload allows accurately and before intubation identifying COVID-19 patients at high risk for ECMO use or in-hospital death despite the use of MV.
Subject(s)
COVID-19/mortality , Interleukin-6/blood , RNA, Viral/metabolism , SARS-CoV-2/genetics , Adult , Aged , Aged, 80 and over , Area Under Curve , COVID-19/pathology , COVID-19/virology , Female , Hospital Mortality , Humans , Male , Middle Aged , Oxygen Consumption , Prognosis , Prospective Studies , ROC Curve , Respiration, Artificial , SARS-CoV-2/isolation & purification , Viral LoadABSTRACT
BACKGROUND: COVID-19 pneumonia has lesions with a decreased blood flow. Dual-energy computed tomography is suitable to elucidate the pathogenesis of COVID-19 pneumonia because it highlights the blood flow changes in organs. We report the dual-energy computed tomography findings of a successfully treated case of COVID-19 pneumonia. CASE PRESENTATION: An obese 49-year-old man with COVID-19 pneumonia was transferred from another hospital on day 11 after onset of illness. Although he was hypoxemic (PaO2/FiO2 = 100), tracheal intubation was not performed after anticipating difficulty in weaning from mechanical ventilation. Prone position therapy and nasal high flow therapy were administered, and the patient was discharged after his condition improved. Dual-energy computed tomography was performed three times during hospitalization, and it revealed improvement in the blood flow defect, unlike plain computed tomography that did not show much improvement. CONCLUSION: Dual-energy computed tomography can assess perfusion in COVID-19 pneumonia in real time and may be able to predict its severity.
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Disturbance of the daily cycles in sleep and wakefulness induced by conditions such as shift work and jet lag can increase the risk of affective disorders including anxiety and depression. The way such circadian disorganization disrupts the regulation of mood, however, is not well understood. More specifically, the impact of circadian disorganization on the daily rhythms of the neuronal function that controls mood remains unclear. We therefore investigated the effects of circadian disorganization on expression rhythms of clock genes as well as immediate early genes (IEGs) in several mood-controlling regions of the brain. To introduce circadian disorganization of behaviors, we exposed male C57BL/6J mice to chronic reversal of the light-dark cycle and we found a marked negative mood phenotype in these mice. Importantly, the most adverse effect of circadian disorganization on expression rhythms of clock and IEGs was observed in the prefrontal cortex (PFC) when compared to that in other mood-related areas of the brain. Dysregulation of molecular rhythms in the PFC is therefore suggested to be associated with the development of mood disorders in conditions including shift work and jet lag.
Subject(s)
Circadian Clocks , Circadian Rhythm , Animals , Male , Mice , Mice, Inbred C57BL , Prefrontal Cortex , Sleep , WakefulnessABSTRACT
Smad3 has circadian expression; however, whether Smad3 affects the expression of clock genes is poorly understood. Here, we investigated the regulatory mechanisms between Smad3 and the clock genes Dec1, Dec2, and Per1. In Smad3 knockout mice, the amplitude of locomotor activity was decreased, and Dec1 expression was decreased in the suprachiasmatic nucleus, liver, kidney, and tongue compared with control mice. Conversely, Dec2 and Per1 expression was increased compared with that of control mice. In Smad3 knockout mice, immunohistochemical staining revealed that Dec1 expression decreased, whereas Dec2 and Per1 expression increased in the endothelial cells of the kidney and liver. In NIH3T3 cells, Smad3 overexpression increased Dec1 expression, but decreased Dec2 and Per1 expression. In a wound-healing experiment that used Smad3 knockout mice, Dec1 expression decreased in the basal cells of squamous epithelium, promoting wound healing of the mucosa. Finally, the migration and proliferation of Smad3 knockdown squamous carcinoma cells was suppressed by Dec1 overexpression but was promoted by Dec2 overexpression. Dec1 overexpression decreased E-cadherin and proliferating cell nuclear antigen expression, whereas these expression levels were increased by Dec2 overexpression. These results suggest Smad3 is relevant to circadian rhythm and regulates cell migration and proliferation through Dec1, Dec2, and Per1 expression.
Subject(s)
Basic Helix-Loop-Helix Transcription Factors/metabolism , Cell Movement , Cell Proliferation , Epithelial Cells/cytology , Homeodomain Proteins/metabolism , Period Circadian Proteins/metabolism , Smad3 Protein/physiology , Transcription Factors/metabolism , Animals , Basic Helix-Loop-Helix Transcription Factors/genetics , Cells, Cultured , Circadian Rhythm , Epithelial Cells/metabolism , Female , Gene Expression Regulation , Homeodomain Proteins/genetics , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , NIH 3T3 Cells , Period Circadian Proteins/genetics , Transcription Factors/geneticsABSTRACT
The daily rhythm of glucose metabolism is governed by the circadian clock, which consists of cell-autonomous clock machineries residing in nearly every tissue in the body. Disruption of these clock machineries either environmentally or genetically induces the dysregulation of glucose metabolism. Although the roles of clock machineries in the regulation of glucose metabolism have been uncovered in major metabolic tissues, such as the pancreas, liver, and skeletal muscle, it remains unknown whether clock function in non-major metabolic tissues also affects systemic glucose metabolism. Here, we tested the hypothesis that disruption of the clock machinery in the heart might also affect systemic glucose metabolism, because heart function is known to be associated with glucose tolerance. We examined glucose and insulin tolerance as well as heart phenotypes in mice with heart-specific deletion of Bmal1, a core clock gene. Bmal1 deletion in the heart not only decreased heart function but also led to systemic insulin resistance. Moreover, hyperglycemia was induced with age. Furthermore, heart-specific Bmal1-deficient mice exhibited decreased insulin-induced phosphorylation of Akt in the liver, thus indicating that Bmal1 deletion in the heart causes hepatic insulin resistance. Our findings revealed an unexpected effect of the function of clock machinery in a non-major metabolic tissue, the heart, on systemic glucose metabolism in mammals.
Subject(s)
ARNTL Transcription Factors/deficiency , Blood Glucose/metabolism , Circadian Rhythm , Insulin Resistance , Myocardium/metabolism , ARNTL Transcription Factors/genetics , Animals , Behavior, Animal , Cells, Cultured , Circadian Rhythm/genetics , Genotype , Heart Failure/blood , Heart Failure/genetics , Heart Failure/physiopathology , Hyperglycemia/blood , Hyperglycemia/genetics , Insulin Resistance/genetics , Liver/metabolism , Mice, Inbred C57BL , Mice, Knockout , Phenotype , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Time FactorsABSTRACT
In the present study, the effects of both single (6 mmol L-serine/10 ml/kg orally administrated) and chronic (2% L-serine solution freely given for 28 days) treatments on depression-like behavior were evaluated in Wistar rats, representing the control, and Wistar Kyoto rats, representing an animal model of depression. Both single and chronic L-serine treatments decreased the duration of immobility, which is an index of a depressive-like state, in the forced swimming test in both strains. However, the decreases in the duration of immobility appear to be regulated differently by the different mechanisms involved in single and chronic L-serine treatments. In the prefrontal cortex and hippocampus, single L-serine treatment increased the concentrations of L-serine, but not D-serine, while chronic L-serine treatment increased those of D-serine, but not L-serine. These data suggest that the antidepressant-like effects of single and chronic L-serine treatments may have been induced by the increased L-serine and D-serine concentrations, respectively, in the brain. In addition, chronic L-serine treatment increased cystathionine concentrations in the hippocampus and prefrontal cortex in Wistar rats, but not in Wistar Kyoto rats, suggesting that Wistar Kyoto rats have an abnormality in the serine-cystathionine metabolic pathway. In conclusion, single and chronic L-serine treatments may induce antidepressant-like effects via the different mechanisms related to serine metabolism in the brain.
Subject(s)
Antidepressive Agents/pharmacology , Depression/drug therapy , Hippocampus/drug effects , Prefrontal Cortex/drug effects , Serine/pharmacology , Administration, Oral , Animals , Antidepressive Agents/metabolism , Behavior, Animal/drug effects , Cystathionine/metabolism , Depression/metabolism , Depression/physiopathology , Disease Models, Animal , Drug Administration Schedule , Hippocampus/metabolism , Hippocampus/physiopathology , Male , Motor Activity/drug effects , Prefrontal Cortex/metabolism , Prefrontal Cortex/physiopathology , Rats , Rats, Inbred WKY , Rats, Wistar , Serine/metabolism , Stereoisomerism , SwimmingABSTRACT
Bright light therapy is used as the primary treatment for seasonal affective disorder; however, the mechanisms underlying its antidepressant effect are not fully understood. Previously, we found that C57BL/6J mice exhibit increased depression-like behavior during a short-day condition (SD) and have lowered brain serotonin (5-HT) content. This study analyzed the effect of bright light on depression-like behaviors and the brain serotonergic system using the C57BL/6J mice. In the mice maintained under SD, bright light treatment (1000 lx, daily 1 h exposure) for 1 week reduced immobility time in the forced swimming test and increased intake of saccharin solution in a saccharin intake test. However, the light treatment did not modify 5-HT content and selective 5-HT uptake in the amygdala, or temporal patterns of core body temperature and wheel-running activity throughout a day. In the next experiment, we attempted to enhance the effect of bright light by using L-serine, a precursor of D-serine that acts as an N-methyl-D-aspartic acid receptor coagonist. Daily subcutaneous injection of L-serine for 2 weeks prior to the bright light strongly reduced the immobility time in the forced swimming test, suggesting a synergistic effect of light and L-serine. Furthermore, bright light increased the total number of 5-HT-immunoreactive cells and cells that had colocalized 5-HT and c-Fos immunosignals in several subregions of the raphe nuclei. These effects were potentiated by prior injection of L-serine. These data suggest that the bright light may elicit an antidepressant-like effect via enhanced 5-HT signals in the brain and L-serine can enhance these effects.
Subject(s)
Phototherapy/methods , Seasonal Affective Disorder/therapy , Serine/pharmacology , Animals , Antidepressive Agents/pharmacology , Behavior, Animal/drug effects , Brain/drug effects , Disease Models, Animal , Fluoxetine/pharmacology , Light , Male , Mice , Mice, Inbred C57BL , Random Allocation , Seasonal Affective Disorder/drug therapy , Seasonal Affective Disorder/metabolism , Serotonin/metabolism , Selective Serotonin Reuptake Inhibitors/pharmacologyABSTRACT
In mammals, short photoperiod is associated with high depression- and anxiety-like behaviours with low levels of the brain serotonin and its precursor tryptophan (Trp). Because the brain Trp levels are regulated by its ratio to large neutral amino acids (Trp:LNAA) in circulation, this study elucidated whether diets of various protein sources that contain different Trp:LNAA affect depression- and anxiety-like behaviours in C57BL/6J mice under short-day conditions (SD). In the control mice on a casein diet, time spent in the central area in the open field test (OFT) was lower in the mice under SD than in those under long-day conditions (LD), indicating that SD exposure induces anxiety-like behaviour. The SD-induced anxiety-like behaviour was countered by an α-lactalbumin diet given under SD. In the mice that were on a gluten diet before transition to SD, the time spent in the central area in the OFT under SD was higher than that in the SD control mice. Alternatively, mice that ingested soya protein before the transition to SD had lower immobility in the forced swim test, a depression-like behaviour, compared with the SD control. Analysis of Trp:LNAA revealed lower Trp:LNAA in the SD control compared with the LD control, which was counteracted by an α-lactalbumin diet under SD. Furthermore, mice on gluten or soya protein diets before transition to SD exhibited high Trp:LNAA levels in plasma under SD. In conclusion, ingestion of specific proteins at different times relative to photoperiodic transition may modulate anxiety- and/or depression-like behaviours, partially through changes in plasma Trp:LNAA.