Combined use of tyrosine kinase inhibitors with PD-(L)1 blockade increased the risk of thyroid dysfunction in PD-(L)1 blockade: a prospective study.

BACKGROUND: Anti-programmed cell death-1 (ligand-1) antibody [PD-(L)1-Ab] can cause destructive thyroiditis and/or hypothyroidism. In addition, tyrosine kinase inhibitors (TKIs) frequently induce hypothyroidism. The aim of this prospective study is to examine the incidence and clinical characteristics of thyroid dysfunction induced by combination therapy of a PD-(L)1-Ab and TKI [PD-(L)1-Ab/TKI]. METHODS: A total of 757 patients treated with PD-(L)1-Ab or PD-(L)1-Ab/TKI were evaluated for anti-thyroid antibodies (ATAs) at baseline and for thyroid function for 48 weeks after treatment initiation and then observed until the last visit. RESULTS: The cumulative incidences of destructive thyroiditis [4/23 (17.4%) vs. 45/734 (6.1%) patients, p < 0.001], isolated hypothyroidism [10/23 (43.5%) vs. 29/734 (4.0%) patients, p < 0.001], and all thyroid dysfunction [14/23 (60.9%) vs. 74/734 (10.1%) patients, p < 0.001] were significantly higher in the PD-(L)1-Ab/TKI group than PD-(L)1-Ab group, respectively. All patients positive for ATAs at baseline developed thyroid dysfunction after PD-(L)1-Ab/TKI treatment, a significantly higher incidence than that in those negative for ATAs at baseline [4/4 (100%) vs. 10/19 (52.6%) patients, p = 0.026]. CONCLUSIONS: The addition of TKIs increased the risk of thyroid dysfunction induced by PD-(L)1-Ab, with the risk being higher in patients positive for baseline ATAs.

Isolation of azole-resistant Aspergillus spp. from food products.

The prevalence of azole-resistant Aspergillus fumigatus is increasing worldwide and is speculated to be related to the use of azole pesticides. Aspergillus spp., the causative agent of aspergillosis, could be brought into domestic dwellings through food. However, studies on azole-resistant Aspergillus spp. in food products are limited. Therefore, we aimed to isolate Aspergillus spp. from processed foods and commercial agricultural products and performed drug susceptibility tests for azoles. Among 692 food samples, we isolated 99 strains of Aspergillus spp. from 50 food samples, including vegetables (22.9%), citrus fruits (26.3%), cereals (25.5%), and processed foods (1.8%). The isolates belonged to 18 species across eight sections: Aspergillus, Candidi, Clavati, Flavi, Fumigati, Nidulantes, Nigri, and Terrei. The most frequently isolated section was Fumigati with 39 strains, followed by Nigri with 28 strains. Aspergillus fumigatus and A. welwitschiae were the predominant species. Ten A. fumigatus and four cryptic strains, four A. niger cryptic strains, two A. flavus, and four A. terreus strains exceeded epidemiological cutoff values for azoles. Aspergillus tubingensis, A. pseudoviridinutans, A. lentulus, A. terreus, and N. hiratsukae showed low susceptibility to multi-azoles. Foods containing agricultural products were found to be contaminated with Aspergillus spp., with 65.3% of isolates having minimal inhibitory concentrations below epidemiological cutoff values. Additionally, some samples harbored azole-resistant strains of Aspergillus spp. Our study serves as a basis for elucidating the relationship between food, environment, and clinically important Aspergillus spp.

Evaluation of antifungal activity of cerium oxide nanoparticles and associated cellular responses.

Cerium oxide nanoparticles (CeO2), as a metal oxide nanomaterial, are increasingly used for various industrial and biomedical applications. Although their cytotoxicity to bacteria and the associated mechanisms have attracted particular attention, the mechanisms behind their antifungal effects have remained unclear. This study investigated the antifungal properties of CeO2, focusing on Aspergillus oryzae. CeO2 inhibited fungal spore germination on solid substrates, and the effect was fungistatic rather than fungicidal. CeO2 inhibited fungal growth, especially under UV irradiation, and induced reactive oxygen species (ROS) production. Tocopherol reduced the intracellular ROS levels and the growth-inhibitory effects of CeO2, suggesting that ROS are involved in these growth-inhibitory effects. Transcriptomic analysis revealed upregulated expression of genes related to phospholipases and phosphate metabolism. CeO2 affected phosphate ion concentration in the medium, potentially influencing cellular responses. This research provided valuable insights into the antifungal effects of CeO2 application, which differ from those of conventional photocatalysts like TiO2.

A machine learning approach for predicting treatment response of hyponatremia.

Hyponatremia leads to severe central nervous system disorders and requires immediate treatment in some cases. However, a rapid increase in serum sodium (s-Na) concentration could cause osmotic demyelination syndrome. To achieve a safety hyponatremia treatment, we develop a prediction model of s-Na concentration using a machine learning. Among the 341 and 47 patients admitted to two tertiary hospitals for hyponatremia treatment (s-Na <130 mEq/L), those who were admitted to the general unit with urine sodium <20 mEq/L or treated with desmopressin were excluded. Ultimately, 74 and 15 patients (342 and 146 6-hourly datasets) were included in the learning and validation data, respectively. We trained the prediction model using three regression algorithms for shallow machine learning to predict s-Na every 6 h during treatment with the data of patients with hyponatremia (median s-Na: 112.5 mEq/L; range: 110.0-116.8 mEq/L) from one hospital. The model was validated externally using the data of patients with hyponatremia (median s-Na: 117.0 mEq/L; range: 112.9-120.0 mEq/L) from another hospital. Using 5-7 predictors (water intake, sodium intake, potassium intake, urine volume, s-Na concentration, serum potassium concentration, serum chloride concentration), the support vector regression model showed the best performance overall (root mean square error = 0.05396; R2 = 0.92), followed by the linear regression and regression tree models. The predicted s-Na levels, using explainable machine learning algorithms and clinically accessible parameters, correlated well with the actual levels. Thus, our model could be applied to the treatment of hyponatremia in clinical practice.

Changes in TgAb and TPOAb titers are greater in thyrotoxicosis than isolated hypothyroidism induced by PD-1 blockade.

Anti-thyroglobulin antibodies (TgAb) and/or anti-thyroid peroxidase antibodies (TPOAb) positivity at baseline is a risk marker for thyroid immune-related adverse events (thyroid-irAEs) in anti-programmed cell death-1 antibody (PD-1-Ab) treatment; however, it is unknown if TgAb and TPOAb titers are associated with clinical characteristics of thyroid-irAEs. Among 586 patients treated with PD-1-Ab at Nagoya University Hospital between 2 November 2015 and 30 September 2021, 57 patients developed thyroid-irAEs (thyrotoxicosis [n = 38]; hypothyroidism without prior thyrotoxicosis {isolated hypothyroidism} [n = 19]) in whom thyroid function, and TgAb and TPOAb titers were determined at baseline and at the onset. The changes in TgAb (median, 54.8 vs. 0.2 IU/mL; p = 0.002) and TPOAb titers (31.6 vs. 0 IU/mL; p = 0.032) from baseline to onset of developing thyroid-irAEs were greater in patients with thyrotoxicosis than patients with isolated hypothyroidism. Higher TgAb and TPOAb titers, and the TgAb titer at baseline were associated with an earlier onset of thyrotoxicosis and higher peak free thyroxine levels, respectively. Twenty-eight patients who developed hypothyroidism after thyrotoxicosis had higher TgAb (54.5 vs. 10.7 IU/mL; p = 0.011) and TPOAb titers at baseline (46.1 vs. 9.0 IU/mL; p < 0.001) and greater changes in TgAb (61.7 vs. 7.8 IU/mL; p = 0.025) and TPOAb titers (52.8 vs. -0.8 IU/mL; p < 0.001) than patients who did not develop hypothyroidism. The TgAb titer at baseline and changes in the TgAb and TPOAb titers were greater in patients with thyrotoxicosis than patients with isolated hypothyroidism, suggesting that the magnitude of the thyroid autoimmune response reflects the clinical types of thyroid-irAEs.

Response to endoplasmic reticulum stress in arginine vasopressin neurons.

Arginine vasopressin (AVP) is an antidiuretic hormone synthesized principally in the hypothalamic supraoptic and paraventricular nuclei. The immunoglobulin heavy chain binding protein (BiP), one of the most abundant endoplasmic reticulum (ER) chaperones, is highly expressed in AVP neurons, even under basal conditions. Moreover, its expression is upregulated in proportion to the increase in AVP expression under dehydration. These data suggest that AVP neurons are constantly exposed to ER stress. BiP knockdown in AVP neurons induces ER stress and autophagy, resulting in AVP neuronal loss, indicating that BiP is pivotal in maintaining the AVP neuron system. Furthermore, inhibition of autophagy after BiP knockdown exacerbates AVP neuronal loss, suggesting that autophagy induced under ER stress is a protective cellular mechanism by which AVP neurons cope with ER stress. Familial neurohypophysial diabetes insipidus (FNDI) is an autosomal dominant disorder caused by mutations in the AVP gene. It is characterized by delayed-onset progressive polyuria and eventual AVP neuronal loss. In AVP neurons of FNDI model mice, mutant protein aggregates are confined to a specific compartment of the ER, called the ER-associated compartment (ERAC). The formation of ERACs contributes to maintaining the function of the remaining intact ER, and mutant protein aggregates in ERACs undergo autophagic-lysosomal degradation without isolation or translocation from the ER, representing a novel protein degradation system in the ER.

A retrospective study on tolvaptan prescription in clinical practice in patients with syndrome of inappropriate secretion of antidiuretic hormone (SIADH) using the Japanese claims database.

We aimed to survey the status of tolvaptan administration in routine clinical practice since the approval of a novel indication for treating syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in Japan. Data from a population of 3,152 patients aged ≥18 years and diagnosed with SIADH between July 1, 2020 and June 30, 2021 were extracted from a Japanese database. Tolvaptan was administered to 586 patients while 2,566 patients were followed up without tolvaptan. In the tolvaptan-treated group, the standard initial doses were 3.75 mg and 7.5 mg in 290 (49.5%) and 250 (42.7%) patients, respectively. The dose was increased in 112 (38.6%) and 71 (28.4%) and decreased in 8 (2.8%) and 46 (18.4%) of patients with 3.75 and 7.5 mg initial doses, respectively. Of the total 586 SIADH patients treated with tolvaptan, serum sodium concentrations were analyzed in 60 patients. In both treatment groups of 3.75 and 7.5 mg initial doses, the serum sodium concentration was elevated from the second day of treatment and reached 135 mEq/L on the fourth day, which was maintained for 2 weeks. Rapid correction of hyponatremia (>10 mEq/L increase in serum sodium concentration over 1 day or >18 mEq/L increase over 2 days) occurred in 26.7% patients with a 7.5 mg initial dose (4 of 15 patients) but not in the patients with a 3.75 mg initial dose (n = 16), suggesting that an initial dose of 3.75 mg of tolvaptan may be a better choice for the safe and proper correction of hyponatremia.

Mineralocorticoids induce polyuria by reducing apical aquaporin-2 expression of the kidney in partial vasopressin deficiency.

The symptoms of diabetes insipidus may be masked by the concurrence of adrenal insufficiency and emerge after the administration of hydrocortisone, occasionally at high doses. To elucidate the mechanism underlying polyuria induced by the administration of high-dose corticosteroids in the deficiency of arginine vasopressin (AVP), we first examined the secretion of AVP in three patients in whom polyuria was observed only after the administration of high-dose corticosteroids. Next, we examined the effects of dexamethasone or aldosterone on water balance in wild-type and familial neurohypophyseal diabetes insipidus (FNDI) model mice. A hypertonic saline test showed that AVP secretion was partially impaired in all patients. In one patient, there were no apparent changes in AVP secretion before and after the administration of high-dose corticosteroids. In FNDI mice, unlike dexamethasone, the administration of aldosterone increased urine volumes and decreased urine osmolality. Immunohistochemical analyses showed that, after the administration of aldosterone in FNDI mice, aquaporin-2 expression was decreased in the apical membrane and increased in the basolateral membrane in the collecting duct. These changes were not observed in wild-type mice. The present data suggest that treatment with mineralocorticoids induces polyuria by reducing aquaporin-2 expression in the apical membrane of the kidney in partial AVP deficiency.

A novel Zn2-Cys6 transcription factor clcA contributes to copper homeostasis in Aspergillus fumigatus.

The filamentous fungus Aspergillus fumigatus is the most important pathogenic fungus among Aspergillus species associated with aspergillosis. A. fumigatus is exposed to diverse environmental stresses in the hosts during infection such as an excess of essential metal copper. To gain further insights into copper homeostasis, we generated an A. fumigatus laboratory evolved strain with increased fitness in copper stress, and identified the mutation in a Zn2-Cys6 type transcription factor clcA. We examined the role of clcA using the evolved and ∆clcA strains. The ∆clcA strain exhibited defective growth on minimal medium, PDA and copper-repleted medium, and defective conidiogenesis and conidial pigmentation. We found that clcA was required for the expressions of genes involved in conidiogenesis, conidial pigmentation, and transporters cdr1B and mfsB related to azole resistance. clcA was dispensable for the virulence in silkworm infection model. We report here that clcA plays an important role in hyphal growth, conidiogenesis, and copper adaptation.

Dysfunction of Ras-GAP protein AfgapA contributes to hypoxia fitness in Aspergillus fumigatus.

The filamentous fungus Aspergillus fumigatus is the most important pathogenic fungus among Aspergillus species associated with aspergillosis. A. fumigatus must adapt to hypoxic microenvironments to survive and thrive in human lungs. To gain further insights into hypoxic adaptation, we generated a laboratory-evolved strain (Afs35-G20) harboring hypoxia fitness, and identified a nonsense mutation in AfgapA encoding a Ras-GAP protein, which could result in the deletion of 22 amino acids at the C-terminus. We investigated the role of AfgapA in hypoxia fitness by constructing Afs35-G20-AfgapAWT, and ∆AfgapA. Indeed, the hypoxia fitness of Afs35-G20 was reversed by introducing AfgapAWT. ∆AfgapA exhibited greater hypoxia fitness and hypervirulence in the silkworm infection model, indicating that AfgapA is responsible for hypoxia fitness, particularly in liquid cultures. Taken together, the AfgapA dysfunction may lead to the downregulation of its Ras substrate(s), reflecting several phenotypes such as increased hypoxia fitness, hypervirulence, poor conidiation, and conidial pigmentation. Here, we report the function of a Ras-GAP protein AfgapA in A. fumigatus for the first time.

Antibacterial diphenyl ether production induced by co-culture of Aspergillus nidulans and Aspergillus fumigatus.

Fungi are a rich source of secondary metabolites with potent biological activities. Co-culturing a fungus with another microorganism has drawn much attention as a practical method for stimulating fungal secondary metabolism. However, in most cases, the molecular mechanisms underlying the activation of secondary metabolite production in co-culture are poorly understood. To elucidate such a mechanism, in this study, we established a model fungal-fungal co-culture system, composed of Aspergillus nidulans and Aspergillus fumigatus. In the co-culture of A. nidulans and A. fumigatus, production of antibacterial diphenyl ethers was enhanced. Transcriptome analysis by RNA-sequencing showed that the co-culture activated expression of siderophore biosynthesis genes in A. fumigatus and two polyketide biosynthetic gene clusters (the ors and cic clusters) in A. nidulans. Gene disruption experiments revealed that the ors cluster is responsible for diphenyl ether production in the co-culture. Interestingly, the ors cluster was previously reported to be upregulated by co-culture of A. nidulans with the bacterium Streptomyces rapamycinicus; orsellinic acid was the main product of the cluster in that co-culture. In other words, the main product of the ors cluster was different in fungal-fungal and bacterial-fungal co-culture. The genes responsible for biosynthesis of the bacterial- and fungal-induced polyketides were deduced using a heterologous expression system in Aspergillus oryzae. The molecular genetic mechanisms that trigger biosynthesis of two different types of compounds in A. nidulans in response to the fungus and the bacterium were demonstrated, which provides an insight into complex secondary metabolic response of fungi to microorganisms. KEY POINTS: • Co-culture of two fungal species triggered antibiotic diphenyl ether production. • The co-culture affected expression levels of several genes for secondary metabolism. • Gene cluster essential for induction of the antibiotics production was determined.

Adult-onset autoimmune diabetes identified by glutamic acid decarboxylase autoantibodies: a retrospective cohort study.

AIMS/HYPOTHESIS: Patients with GAD antibodies (GADAb) showing clinical features of type 2 diabetes typically exhibit progression to an insulin-dependent state in several months or years. This condition is diagnosed as slowly progressive insulin-dependent (type 1) diabetes mellitus (SPIDDM) or latent autoimmune diabetes in adults, a subtype of adult-onset autoimmune diabetes. However, some patients diagnosed with adult-onset autoimmune diabetes do not progress to an insulin-dependent state. We conducted a retrospective cohort study to identify patients with non-insulin-dependent diabetes among those diagnosed with adult-onset autoimmune diabetes using measurable indicators in routine clinical practice. METHODS: We surveyed data from the electronic medical records of all patients with GADAb from eight medical centres in Japan for selecting and analysing patients who matched the diagnostic criteria of SPIDDM. RESULTS: Overall, 345 patients were analysed; of these, 162 initiated insulin therapy (insulin therapy group), whereas 183 did not (non-insulin therapy group) during the follow-up period (median 3.0 years). Patients in the non-insulin therapy group were more likely to be male and presented a later diabetes onset, shorter duration of diabetes, higher BMI, higher blood pressure levels, lower HbA1c levels, lower GADAb levels and lesser antidiabetic agent use than those in the insulin therapy group when GADAb was first identified as positive. A Cox proportional hazards model showed that BMI, HbA1c levels and GADAb levels were independent factors for progression to insulin therapy. Kaplan-Meier analyses revealed that 86.0% of the patients with diabetes having GADAb who presented all three factors (BMI ≥ 22 kg/m2, HbA1c < 75 mmol/mol [9.0%] and GADAb <10.0 U/ml) did not require insulin therapy for 4 years. CONCLUSIONS/INTERPRETATION: Higher BMI (≥22 kg/m2), lower HbA1c (<75 mmol/mol [9.0%]) and lower GADAb levels (<10.0 U/ml) can predict a non-insulin-dependent state for at least several years in Japanese patients with diabetes having GADAb.

Identification of Novel Mutations Contributing to Azole Tolerance of Aspergillus fumigatus through In Vitro Exposure to Tebuconazole.

Azole resistance of Aspergillus fumigatus is a global problem. The major resistance mechanism is through cytochrome P450 14-α sterol demethylase Cyp51A alterations such as a mutation(s) in the gene and the acquisition of a tandem repeat in the promoter. Although other azole tolerance and resistance mechanisms, such as the hmg1 (a 3-hydroxy-3-methylglutaryl coenzyme-A reductase gene) mutation, are known, few reports have described studies elucidating non-Cyp51A resistance mechanisms. This study explored genes contributing to azole tolerance in A. fumigatus by in vitro mutant selection with tebuconazole, an azole fungicide. After three rounds of selection, we obtained four isolates with low susceptibility to tebuconazole. These isolates also showed low susceptibility to itraconazole and voriconazole. Comparison of the genome sequences of the isolates obtained and the parental strain revealed a nonsynonymous mutation in MfsD, a major facilitator superfamily protein (Afu1g11820; R337L mutation [a change of R to L at position 337]), in all isolates. Furthermore, nonsynonymous mutations in AgcA, a mitochondrial inner membrane aspartate/glutamate transporter (Afu7g05220; E535Stop mutation), UbcD, a ubiquitin-conjugating enzyme E2 (Afu3g06030; T98K mutation), AbcJ, an ABC transporter (Afu3g12220; G297E mutation), and RttA, a putative protein responsible for tebuconazole tolerance (Afu7g04740; A83T mutation), were found in at least one isolate. Disruption of the agcA gene led to decreased susceptibility to azoles. Reconstruction of the A83T point mutation in RttA led to decreased susceptibility to azoles. Reversion of the T98K mutation in UbcD to the wild type led to decreased susceptibility to azoles. These results suggest that these mutations contribute to lowered susceptibility to medical azoles and agricultural azole fungicides.

Intimate genetic relationships and fungicide resistance in multiple strains of Aspergillus fumigatus isolated from a plant bulb.

Fungal infections are increasingly dangerous because of environmentally dispersed resistance to antifungal drugs. Azoles are commonly used antifungal drugs, but they are also used as fungicides in agriculture, which may enable enrichment of azole-resistant strains of the human pathogen Aspergillus fumigatus in the environment. Understanding of environmental dissemination and enrichment of genetic variation associated with azole resistance in A. fumigatus is required to suppress resistant strains. Here, we focused on eight strains of azole-resistant A. fumigatus isolated from a single tulip bulb for sale in Japan. This set includes strains with TR34 /L98H/T289A/I364V/G448S and TR46 /Y121F/T289A/S363P/I364V/G448S mutations in the cyp51A gene, which showed higher tolerance to several azoles than strains harbouring TR46 /Y121F/T289A mutation. The strains were typed by microsatellite typing, single nucleotide polymorphism profiles, and mitochondrial and nuclear genome analyses. The strains grouped differently using each typing method, suggesting historical genetic recombination among the strains. Our data also revealed that some strains isolated from the tulip bulb showed tolerance to other classes of fungicides, such as QoI and carbendazim, followed by related amino acid alterations in the target proteins. Considering spatial-temporal factors, plant bulbs are an excellent environmental niche for fungal strains to encounter partners, and to obtain and spread resistance-associated mutations.

Peripheral combination treatment of leptin and an SGLT2 inhibitor improved glucose metabolism in insulin-dependent diabetes mellitus mice.

We investigated whether peripheral combination treatment of a sodium-glucose cotransporter 2 (SGLT2) inhibitor and leptin improves glucose metabolism in insulin-dependent diabetes mellitus (IDDM) model mice. Twelve-week-old male C57BL6 mice were intraperitoneally administered a high dose of streptozotocin to produce IDDM. IDDM mice were then divided into five groups: SGLT2 inhibitor treatment alone, leptin treatment alone, leptin and SGLT2 inhibitor co-treatment, untreated IDDM mice, and healthy mice groups. The blood glucose (BG) level at the end of the dark cycle was measured, and a glucose tolerance test (GTT) was performed and compared between the five groups. Leptin was peripherally administered at 20 µg/day using an osmotic pump, and an SGLT2 inhibitor, ipragliflozin, was orally administered at 3 mg/kg/day. Monotherapy with SGLT2 inhibitor or leptin significantly improved glucose metabolism in mice as evaluated by BG and GTT compared with the untreated group, whereas the co-treatment group with SGLT2 inhibitor and leptin further improved glucose metabolism as compared with the monotherapy group. Notably, glucose metabolism in the co-treatment group improved to the same level as that in the healthy mice group. Thus, peripheral combination treatment with leptin and SGLT2 inhibitor improved glucose metabolism in IDDM mice without the use of insulin.

Deficiency of WFS1 leads to the impairment of AVP secretion under dehydration in male mice.

Wolfram syndrome (WS) is mainly caused by mutations in the WFS1 gene and characterized by diabetes mellitus, optic atrophy, hearing loss, and central diabetes insipidus (CDI). WFS1 is an endoplasmic reticulum (ER)-resident transmembrane protein, and Wfs1 knockout (Wfs1-/-) mice, which have been used as a mouse model for WS, reportedly manifested impairment of glucose tolerance due to pancreatic ß-cell loss. In the present study, we examined water balance, arginine vasopressin (AVP) secretion, and ER stress in AVP neurons of the hypothalamus in Wfs1-/- mice. There were no differences in urine volumes between Wfs1-/- and wild-type mice with free access to water. Conversely, when mice were subjected to intermittent water deprivation (WD) for 20 weeks, during which water was unavailable for 2 days a week, urine volumes were larger in Wfs1-/- mice, accompanied by lower urine AVP concentrations and urine osmolality, compared to wild-type mice. The mRNA expression of immunoglobulin heavy chain binding protein, a marker of ER stress, was significantly increased in the supraoptic nucleus and paraventricular nuclei in Wfs1-/- mice compared to wild-type mice after WD. Our results thus showed that Wfs1 knockout leads to a decrease in AVP secretion during dehydration, which could explain in part the mechanisms by which Wfs1 mutations cause CDI in humans.

Anti-thyroid antibodies and thyroid echo pattern at baseline as risk factors for thyroid dysfunction induced by anti-programmed cell death-1 antibodies: a prospective study.

BACKGROUND: Anti-programmed cell death-1 (PD-1) antibodies can cause thyroid dysfunction. However, no predictive biomarkers enabling stratification of thyroid dysfunction risk have been identified. METHODS: A total of 209 patients treated with an anti-PD-1 antibody were evaluated for anti-thyroid antibodies at baseline and prospectively for thyroid function every 6 weeks for 24 weeks after treatment initiation, and then observed until the visits stopped. Thyroid ultrasonography was performed if the patient was positive for anti-thyroid antibodies at baseline. RESULTS: Of the 209 patients, 19 (9.1%) developed thyroid dysfunction (destructive thyroiditis or hypothyroidism). The cumulative incidence of thyroid dysfunction was significantly higher in patients who were positive vs. negative for anti-thyroid antibodies (15/44 [34.1%] vs. 4/165 [2.4%], p < 0.001). Forty-two patients positive for anti-thyroid antibodies at baseline were divided into two groups according to the presence of an irregular echo pattern. The cumulative incidence of thyroid dysfunction was significantly higher in those with an irregular vs. a regular echo pattern (13/23 [56.5%] vs. 1/19 [5.3%], p = 0.001). None of the patients developed thyroid dysfunction after the initial 24-week period. CONCLUSIONS: The risk of thyroid dysfunction induced by anti-PD-1 antibodies can be predicted by evaluation of anti-thyroid antibodies and the thyroid echo pattern at baseline. TRIAL REGISTRATION: UMIN000019024.

The Cell Wall Integrity Pathway Contributes to the Early Stages of Aspergillus fumigatus Asexual Development.

Aspergillus fumigatus is a major cause of human disease. The survival of this fungus is dependent on the cell wall organization and function of its components. The cell wall integrity pathway (CWIP) is the primary signaling cascade that controls de novo synthesis of the cell wall in fungi. Abundant conidiation is a hallmark in A. fumigatus, and uptake of conidia by a susceptible host is usually the initial event in infection. The formation of conidia is mediated by the development of fungus-specific specialized structures, conidiophores, which are accompanied by cell wall remodeling. The molecular regulation of these changes in cell wall composition required for the rise of conidiophore from the solid surface and to disperse the conidia into the air is currently unknown. Here, we investigated the role of CWIP in conidiation. We show that CWIP pkcAG579R, ΔmpkA, and ΔrlmA mutants displayed reduced conidiation during synchronized asexual differentiation. The transcription factor RlmA directly regulated the expression of regulators of conidiation, including flbB, flbC, brlA, abaA, and rasB, as well as genes involved in cell wall synthesis and remodeling, and this affected the chitin content in aerial hyphae. Phosphorylation of RlmA and MpkA was increased during asexual differentiation. We also observed that MpkA physically associated with the proteins FlbB, FlbC, BrlA, and RasB during this process, suggesting another level of cross talk between the CWIP and asexual development pathways. In summary, our results support the conclusion that one function of the CWIP is the regulation of asexual development in filamentous fungi.IMPORTANCE A remarkable feature of the human pathogen Aspergillus fumigatus is its ability to produce impressive amounts of infectious propagules known as conidia. These particles reach immunocompromised patients and may initiate a life-threatening mycosis. The conidiation process in Aspergillus is governed by a sequence of proteins that coordinate the development of conidiophores. This process requires the remodeling of the cell wall so that the conidiophores can rise and withstand the chains of conidia. The events regulating cell wall remodeling during conidiation are currently unknown. Here, we show that the cell wall integrity pathway (CWIP) components RlmA and MpkA directly contribute to the activation of the conidiation cascade by enabling transcription or phosphorylation of critical proteins involved in asexual development. This study points to an essential role for the CWIP during conidiation and provides further insights into the complex regulation of asexual development in filamentous fungi.

Diagnosis of central diabetes insipidus using a vasopressin radioimmunoassay during hypertonic saline infusion.

Central diabetes insipidus (CDI) is characterized by polyuria and polydipsia caused by impairment of arginine vasopressin (AVP) secretion. In this study, we evaluated plasma AVP concentrations during a hypertonic saline infusion test using a new AVP radioimmunoassay (RIA) which is now available in Japan. Thirteen control subjects, mostly with hypothalamo-pituitary disease but without CDI, and 13 patients with CDI were enrolled in the study. Whether or not subjects had CDI was determined based on the totality of clinical data, which included urine volumes and osmolality. Regression analysis of plasma AVP and serum Na concentrations revealed that the gradient was significantly lower in the CDI group than in the control group. The area under the receiver-operating-characteristic (ROC) curve was 0.99, and the <0.1 gradient cut-off values for the simple regression line to distinguish CDI from control had a 100% sensitivity and a 77% specificity. The ROC analysis with estimated plasma AVP concentrations at a serum Na concentration of 149 mEq/L showed that the area under the ROC curve was 1.0 and the <1.0 pg/mL cut-off values of plasma AVP had a 99% sensitivity and a 95% specificity. We conclude that measurement of AVP by RIA during a hypertonic saline infusion test can differentiate patients with CDI from those without CDI with a high degree of accuracy. Further investigation is required to confirm whether the cut-off values shown in this study are also applicable to a diagnosis of partial CDI or a differential diagnosis between CDI and primary polydipsia.

A Novel Zn2-Cys6 Transcription Factor AtrR Plays a Key Role in an Azole Resistance Mechanism of Aspergillus fumigatus by Co-regulating cyp51A and cdr1B Expressions.

Successful treatment of aspergillosis caused by Aspergillus fumigatus is threatened by an increasing incidence of drug resistance. This situation is further complicated by the finding that strains resistant to azoles, the major antifungal drugs for aspergillosis, have been widely disseminated across the globe. To elucidate mechanisms underlying azole resistance, we identified a novel transcription factor that is required for normal azole resistance in Aspergillus fungi including A. fumigatus, Aspergillus oryzae, and Aspergillus nidulans. This fungal-specific Zn2-Cys6 type transcription factor AtrR was found to regulate expression of the genes related to ergosterol biosynthesis, including cyp51A that encodes a target protein of azoles. The atrR deletion mutant showed impaired growth under hypoxic conditions and attenuation of virulence in murine infection model for aspergillosis. These results were similar to the phenotypes for a mutant strain lacking SrbA that is also a direct regulator for the cyp51A gene. Notably, AtrR was responsible for the expression of cdr1B that encodes an ABC transporter related to azole resistance, whereas SrbA was not involved in the regulation. Chromatin immunoprecipitation assays indicated that AtrR directly bound both the cyp51A and cdr1B promoters. In the clinically isolated itraconazole resistant strain that harbors a mutant Cyp51A (G54E), deletion of the atrR gene resulted in a hypersensitivity to the azole drugs. Together, our results revealed that AtrR plays a pivotal role in a novel azole resistance mechanism by co-regulating the drug target (Cyp51A) and putative drug efflux pump (Cdr1B).