Comprehensive assessment of multiple tryptophan metabolites as potential biomarkers for immune checkpoint inhibitors in patients with non-small cell lung cancer

Purpose

Tryptophan metabolites have immunomodulatory functions, suggesting possible roles in cancer immunity.

Methods

Plasma tryptophan metabolites were measured using liquid chromatography/mass spectrometry before immune checkpoint inhibitors (ICIs) in patients with non-small cell lung cancer (NSCLC).

Results

The 19 patients with NSCLC had significantly lower levels of tryptophan (p = 0.002) and xanthurenic acid (p = 0.032), and a significantly higher level of 3-hydroxyanthranilic acid (3-HAA) (p = 0.028) compared with the 10 healthy volunteers. The patients achieving objective responses had significantly lower levels of 3-HAA than those who did not (p = 0.045). Receiver operating characteristic analyses determined that the cutoff value of 3-HAA for objective response was 35.4 pmol/mL (sensitivity: 87.5% and specificity: 83.3%). The patients with 3-HAA < 35.4 pmol/mL had significantly longer median progression-free survival (7.0 months) than those without (1.6 months, p = 0.022).

Conclusions

Tryptophan metabolites may have a potential for predicting the efficacy of ICIs.

Registration number

University Hospital Medical Information Network Clinical Trial Registry 000026140.

Electronic supplementary material

The online version of this article (10.1007/s12094-020-02421-8) contains supplementary material, which is available to authorized users.

Use of Chromogenic Substrate S-2251 for Determination of Plasminogen Activator in Rat Ovaries

A simple, specific and reproducible method for determination of plasminogen activator activity in rat ovaries has been developed by using the chromogenic substrate S-2251. The two steps of enzymatic reactions, i. e. activation of plasminogen and subsequent hydrolysis of the substrate was performed in one step incubation. A linear relationship was observed between the amount of chromogen produced and activator activity in the range of the optical density from 0.05 to 1.20 for 30 min’s incubation. Endogenous activity of non-specific proteases, plasmin or plasmin inhibitors which might be contained in rat ovaries turned out not to interfere with the specificity of a standardized assay procedure. Reproducibility was firmly established with coefficient of variation not exceeding 10%. Using this method, a marked increase followed by a drastic decrease in the activator activity was shown with rat ovaries around the time of ovulation after the injection of human chorionic gonadotropin.

Comparative Study of Proactivators of the Fibrinolysin System in Three Mammalian Species

Sephadex gel filtration of human plasma gave results suggesting the presence of two proactivators of plasminogen, termed proactivators A and B.

Activity resembling that of proactivator A was found in rabbit plasma, but not in guinea pig plasma.

Plasminogen activators produced by the interaction of proactivator A of human plasma with streptokinase had no caseinolytic or TAMe esterolytic effect.

Proactivator A can be separated in a form apparently free from plasminogen, as shown by the heated fibrin plate test and by immunological analysis. On the other hand, proactivator B concentrates prepared so far are contamined with plasminogen.

Human proactivators appear to be far more susceptible to streptokinase than are rabbit proactivators.

Inhibitors of the fibrinolysin system were observed in the plasmas of all 3 species. These inhibitors are not present in the euglobulin fraction of plasma. Sephadex fractionation of euglobulin fractions results in proactivator preparations that do not contain inhibitors.

Development of the micro pixel chamber based on MEMS technology

Micro pixel chambers (μ-PIC) are gaseous two-dimensional imaging detectors originally manufactured using printed circuit board (PCB) technology. They are used in MeV gamma-ray astronomy, medicalimaging, neutron imaging, the search for dark matter, and dose monitoring. The position resolution of the present μ-PIC is approximately 120 μm (RMS), however some applications require a fine position resolution of less than 100 μm. To this end, we have started to develop a μ-PIC based on micro electro mechanical system (MEMS) technology, which provides better manufacturing accuracy than PCB technology. Our simulation predicted the gains of MEMS μ-PICs to be twice those of PCB μ-PICs at the same anode voltage. We manufactured two MEMS μ-PICs and tested them to study their behavior. In these experiments, we successfully operated the fabricatedMEMS μ-PICs and we achieved a maximum gain of approximately 7×103 and collected their energy spectra under irradiation of X-rays from 55Fe. However, the measured gains of the MEMS μ-PICs were less than half of the values predicted in the simulations. We postulated that the gains of the MEMS μ-PICs are diminished by the effect of the silicon used as a semiconducting substrate.

Effect of sodium-glucose co-transporter-2 inhibitors on impaired ventricular repolarization in people with Type 2 diabetes

AIMS

To test the hypothesis that treatment with a sodium-glucose co-transporter-2 inhibitor would reverse ventricular repolarization heterogeneity, a predictor of cardiovascular mortality, in people with Type 2 diabetes.

METHODS

We retrospectively analysed changes in indices of ventricular repolarization before and after treatment with a sodium-glucose co-transporter-2 inhibitor in 46 people with Type 2 diabetes.

RESULTS

Sodium-glucose co-transporter-2 inhibitor treatment reduced HbA_1c concentration [62±13 mmol/mol (7.7±1.2%) vs 59±16 mmol/mol (7.5±1.4%)], body weight (77.8±13.9 vs 74.7±12.5 kg) and systolic blood pressure (133±18 vs 126±12 mmHg) in the study participants. Heart rate and QTc interval were not changed by sodium-glucose co-transporter-2 inhibitor treatment, but QTc dispersion was significantly reduced (median, 48.8 vs 44.2 ms). Sodium-glucose co-transporter-2 inhibitor treatment reversed QTc dispersion more in participants who had larger QTc dispersion before the treatment. Changes in systolic blood pressure (Spearman's ρ= 0.319; P=0.031), but not in HbA_1c concentration, were correlated with changes in QTc dispersion after sodium-glucose co-transporter-2 inhibitor treatment.

CONCLUSIONS

The findings suggest that sodium-glucose co-transporter-2 inhibitor treatment reverses ventricular repolarization heterogeneity in people with Type 2 diabetes, independently of its effect on glycaemic control. The favourable effect on ventricular repolarization heterogeneity could be the mechanism by which empaglifozin reduced cardiovascular events in a recent study.

Co-circulation of multiple genotypes of African swine fever viruses among domestic pigs in Zambia (2013-2015)

During 2013-2015, several and severe outbreaks of African swine fever (ASF) affected domestic pigs in six provinces of Zambia. Genetic characterization of ASF viruses (ASFVs) using standardized genotyping procedures revealed that genotypes I, II and XIV were associated with these outbreaks. Molecular and epidemiological data suggest that genotype II ASFV (Georgia 2007/1-like) detected in Northern Province of Zambia may have been introduced from neighbouring Tanzania. Also, a genotype II virus detected in Eastern Province of Zambia showed a p54 phylogenetic relationship that was inconsistent with that of p72, underscoring the genetic variability of ASFVs. While it appears genotype II viruses detected in Zambia arose from a domestic pig cycle, genotypes I and XIV possibly emerged from a sylvatic cycle. Overall, this study demonstrates the co-circulation of multiple genotypes of ASFVs, involvement of both the sylvatic and domestic pig cycle in ASF outbreaks in Zambia and possible trans-boundary spread of the disease in south-eastern Africa. Indeed, while there is need for regional or international concerted efforts in the control of ASF, understanding pig marketing practices, pig population dynamics, pig housing and rearing systems and community engagement will be important considerations when designing future prevention and control strategies of this disease in Zambia.

Juxtacortical Chondroma of the Hand: Treatment by Resection of the Tumour and the Adjacent Bone Cortex

A recurrence of a juxtacortical chondroma of the finger after marginal excision prompted us to review the treatment of this condition. Although the recommended treatment is simple curettage or marginal excision, the reported recurrence rate is significantly higher for lesions in the hand than those in other locations and recurrences only occurred in patients who had local treatments which did not include excision of the adjacent bone cortex.

We report five patients with juxtacortical chondroma of the fingers. The first patient underwent marginal excision without resection of the underlying bone cortex. The other four patients underwent intralesional, marginal or wide excisions of tumour with resection of the bone cortex underlying the lesion. Recurrence was only seen in the patient who did not undergo resection of the bone cortex. Resection of the underlying bone cortex after excision of this tumour may be advisable for the treatment of this tumour in the hand to reduce the rate of recurrence.

Relationship between Cnm-positive Streptococcus mutans and cerebral microbleeds in humans

OBJECTIVE

Cerebral hemorrhage has been shown to occur in animals experimentally infected with Streptococcus mutans carrying the collagen-binding Cnm gene. However, the relationship between cerebral microbleeds and oral hygiene, with a focus on Cnm gene-positive S. mutans infection, remains unclear.

MATERIAL AND METHODS

One hundred and thirty-nine subjects participated. The presence or absence of Cnm-positive S. mutans and its collagen-binding activity were investigated using saliva samples, and relationship with cerebral microbleeds detected on MRI investigated, including clinical information and oral parameters.

RESULTS

Fifty-one subjects were identified as Cnm-positive S. mutans carriers (36.7%), with cerebral microbleeds being detected in 43 (30.9%). A significantly larger number of subjects carried Cnm-positive S. mutans in the cerebral microbleeds (+) group. S. mutans with Cnm collagen-binding ability was detected in 39 (28.1%) of all subjects, and the adjusted odds ratio for cerebral microbleeds in the Cnm-positive group was 14.4. Regarding the presence of cerebral microbleeds, no significant differences were noted in the number of remaining teeth, dental caries, or in classic arteriosclerosis risk factors.

CONCLUSIONS

The occurrence of cerebral microbleeds was higher in subjects carrying Cnm-positive S. mutans, indicating that the presence of Cnm-positive S. mutans increases cerebral microbleeds, and is an independent risk for the development of cerebrovascular disorders.

Anisotropic multi-step etching for large-area fabrication of surface microstructures on stainless steel to control thermal radiation

Controlling the thermal radiation spectra of materials is one of the promising ways to advance energy system efficiency. It is well known that the thermal radiation spectrum can be controlled through the introduction of periodic surface microstructures. Herein, a method for the large-area fabrication of periodic microstructures based on multi-step wet etching is described. The method consists of three main steps, i.e., resist mask fabrication via photolithography, electrochemical wet etching, and side wall protection. Using this method, high-aspect micro-holes (0.82 aspect ratio) arrayed with hexagonal symmetry were fabricated on a stainless steel substrate. The conventional wet etching process method typically provides an aspect ratio of 0.3. The optical absorption peak attributed to the fabricated micro-hole array appeared at 0.8 μm, and the peak absorbance exceeded 0.8 for the micro-holes with a 0.82 aspect ratio. While argon plasma etching in a vacuum chamber was used in the present study for the formation of the protective layer, atmospheric plasma etching should be possible and will expand the applicability of this new method for the large-area fabrication of high-aspect materials.

Effect of Heat Treatment on Dilute Solution Properties of Sugar Beet Pectin

Beet Pectin (SBP) polysaccharide. Aqueous solution properties of these samples have been studied using Ubbelohde capillary viscometer in the dilute regime. Intrinsic viscosity [?] was estimated for different SBP solution samples prepared from heat-treated SBP powdered samples with different heating time. Results suggest that heat treatment has a significant effect on solution behavior of SBP samples. Intrinsic viscosities decreased with increasing heating time indicating that heat-treated SBP molecules are compact than the untreated one and the compactness increases with increasing heating time at 80°C. The intrinsic viscosities of these samples were plotted as a function of the corresponding molecular weight of the samples and can be expressed by a power law. The power law exponent was estimated as 1.4 indicating that pectin molecules takes the conformation of stiff polymer chains in dilute solution. Dhaka Univ. J. Sci. 61(1): 117-123, 2013 (January) DOI: http://dx.doi.org/10.3329/dujs.v61i1.15107

Bovine and water buffalo Mx2 genes: polymorphism and antiviral activity

Millennia-long selective pressure of single-strand RNA viruses on the bovine Mx locus has increased the advantages of using the bovine Mx protein to evaluate the ultimate significance of the antiviral role of Mx proteins. The conclusions of research based only on the bovine Mx1 protein showed the need for comprehensive studies that demonstrate the role of all isoforms, individually or together, especially in the presence of a second isoform, the bovine Mx2 gene. This study provides information about bovine and water buffalo Mx2 genes, as well as their allelic polymorphism and basic antiviral potential. Observation of an Mx2 cDNA sequence (2,381 bp) obtained from 15 animals from 11 breeds using primers based on a previous sequence (NCBI accession no. AF335147) revealed several nucleotide substitutions, with eight different alleles and two amino acid exchanges: Gly to Ser at position 302 and Ile to Val at position 354, though the latter was found only in the NCBI database. A water buffalo Mx2 cDNA sequence was identified for the first time, revealing 46 nucleotide substitutions with 12 amino acid variations, in addition to a 9-bp insertion in the 5' untranslated region UTR, compared with the bovine Mx2 cDNA. Transfected 3T3 cells expressing bovine Mx2 mRNAs coding Gly or Ser at position 302, water buffalo Mx2 mRNA, positive control bovine Mx1 mRNA-expressing cells, and negative control parental 3T3 were subjected to infection with recombinant vesicular stomatitis virus (VSVDeltaG*-G), as were empty pCI-neo vector-transfected cells. The positive control and all cells expressing Mx2 mRNAs displayed significantly higher levels of antiviral activity against VSVDeltaG*-G (P < 0.01) than did the negative controls.

A case of plasmacytic hyperplasia arising in a kidney allograft salvaged with immunosuppression reduction alone

Post-transplant lymphoproliferative disorder (PTLD) is a well-known complication of organ transplantation. Plasmacytic hyperplasia (PH) is thought of as the mildest form of PTLD; however, a graftectomy is necessary in most situations. We experienced an interesting case of PH arising in a kidney allograft, which could be relieved with a reduction in immunosuppression. A 27-year-old female underwent a living-related kidney transplantation. A 3-month non-episode protocol biopsy unexpectedly showed the devastating appearance of polymorphic plasma cell infiltration into the graft intersitium, compatible with PH. The PH was located in the graft by radiographic examinations. The infiltration of plasma cell disappeared completely on the 6-month graft biopsy specimen following immunosuppression reduction and the graft is functioning, although it was damaged by a subsequent acute rejection. Our present case indicates that some PTLD can be completely cured with a reduction in immunosuppression alone. The diagnostic modality for the evaluation of PTLD cell extinction is necessary to maintain graft function with adequate immunosuppression thereafter.

Genetic polymorphisms and antiviral activity in the bovine MX1 gene

Bovine MX1 cDNAs consisting of 2280 bp from 11 animals of five breeds and from a cultured cell line were sequenced and compared with previously reported data. Ten nucleotide substitutions were synonymous mutations, and a single nucleotide substitution at 458 resulted in an amino acid exchange of Ile (ATT) and Met (ATG). A 13-bp deletion-insertion mutation was also found in the 3'-UTR. Based on the nucleotide substitutions found in this study, bovine MX1 cDNA was classified into 11 genotypes. A phylogenetic tree of the 11 genotypes suggested that the genotypes observed in Brahman were a great genetic distance from other genotypes. An 18-bp deletion-insertion variation at position 171 was found to be the result of alternative splicing. The 18-bp deletion-insertion is located at the boundary between exon 3 and intron 3. Permanently transfected 3T3 cell lines expressing bovine MX1 mRNA were established to analyse the antiviral potential against VSVDeltaG*-G infection. Transfected cell clones expressing bovine MX1 mRNA showed a significantly smaller number of cells infected with VSVDeltaG*-G compared with the control cells. These results indicate that the bovine MX1 protein has potent antiviral activity.

Native antiviral specificity of chicken Mx protein depends on amino acid variation at position 631

An attempt was made to determine whether amino acid variation at position 631 in the chicken Mx protein definitely influences antiviral specificity, using an artificial mutation technique by which a single amino acid was reciprocally substituted between Ser (AGT) and Asn (AAT) at position 631 of the negative and positive chicken Mx, respectively. Using permanently transfected 3T3 cell lines, the antiviral potential of chicken Mx against vesicular stomatitis virus infection was analysed. The results indicated that the phenotype of antiviral activity depends on the amino acid difference at position 631; that is, the genotype coding Asn at position 631 corresponds to the positive antiviral phenotype, and the genotype coding Ser corresponds to the negative phenotype. The present study has confirmed that the antiviral specificity of chicken Mx protein is determined by an amino acid substitution at the carboxy terminus.

Persistence of viral RNA segments in the central nervous system of mice after recovery from acute influenza A virus infection

One-hundred thirty-seven BALB/c mice were intranasally inoculated with neurotropic avian influenza A virus (H5N3). Thirty-nine of these mice died within 16 days post-inoculation (PID) and 98 of the mice recovered from the infection. To investigate whether viral antigens and genomes persist in the central nervous system (CNS) of recovered mice, immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) methods were performed. Histopathologically, mild interstitial pneumonia and non-suppurative encephalomyelitis restricted to the basal part of the frontal lobe of the cerebrum, brain stem and thoracic spinal cord were observed in BALB/c mice until 40 PID. Small amounts of viral antigens were detected in the brain and spinal cord and some viral RNA segments (NA, NP, M, PA, HA, NS, PB1) were intermittently detected in the CNS until 48 PID. Immunosuppression of these mice by dexamethazone (DEX) treatment did not increase the frequency of detection of the lesions, viral antigens or genomes. These findings suggest that viral genomes of neurovirulent influenza virus persist with restricted transcriptive activity in the CNS of the mice even after clinical recovery from the infection.

Induction of interferon-inducible protein-10 and monokine induced by interferon-gamma from human endothelial cells infected with Influenza A virus

Primary human umbilical vein endothelial cells (HUVECs) were infected with Influenza virus A/Aichi/2/68 (H3N2) in order to determine the role of endothelial cells in mediating inflammation induced upon virus infection. Structural proteins of the virus and mRNA of the M2 protein were detected in the infected cells, indicating that virus infection had occurred in HUVECs. The Influenza A virus-infected HUVECs showed elevated levels of gene expression of interferon (IFN)-inducible protein (IP)-10 and monokine induced by IFN-gamma (Mig), while heat-, formalin- and diethyl ether-inactivated viruses did not enhance the IP-10 and Mig gene expression. The results thus indicate that infection of live Influenza A virus is responsible for elevation of IP-10 and Mig gene expression. The elevation of IP-10 and Mig gene expression in infected HUVECs was not accompanied by the elevation of IFN-gamma gene expression, indicating that the elevation of IP-10 and Mig gene expression was independent of the IFN-gamma pathway.

Rapid, specific and active site-catalyzed effect of tissue-plasminogen activator on hippocampus-dependent learning in mice

In the present study we trained tissue-plasminogen activator (tPA)-knockout (tPA -/-) and wild-type (tPA +/+) male mice in step-down inhibitory avoidance learning, a hippocampus-dependent task. tPA -/- displayed significantly shorter latencies to step down at 90 min, one, two and seven days after training indicating the learning deficit in these animals (P < 0.05 vs tPA +/+). The locomotor activity, the level of anxiety in an elevated-plus maze, as well as the pain threshold did not differ between the two strains of mice. The learning disability of tPA -/- was overcome by more intense training. The learning deficit was also partially restored by limited intrahippocampal delivery of tPA (infused for 2 h before training; P < 0.05 vs control), but not by the delivery of urokinase plasminogen activator, indicating the acute need for tPA in learning. The beneficial effect of tPA was abolished by co-infusion of its inhibitor tPA-STOP, indicating that the facilitatory effect of tPA on learning requires a proteolytic step. However, tPA activity in the hippocampus was not indispensable for effective memory retrieval in tPA-infused tPA -/- mice. Thus, rapid, specific and proteolytic action of tPA facilitates hippocampus-dependent learning, but not retrieval of previously acquired information.

The invasion routes of neurovirulent A/Hong Kong/483/97 (H5N1) influenza virus into the central nervous system after respiratory infection in mice

A/Hong Kong/483/97 (H5N1) influenza virus (HK483) isolated from the third patient during the outbreak of chicken and human influenza in Hong Kong in 1997 was shown to be neurovirulent in mice. HK483 was inoculated intranasally to mice, and the invasion routes of the virus in the central nervous system (CNS) were investigated by immunohistochemical and in situ hybridization. The pathological changes consisted of bronchopneumonia, ganglionitis, and nonpurulent encephalomyelitis of the brain stem and the anterior part of the thoracic cord. Viral antigens and viral nucleic acids (RNA and mRNA) were demonstrated in the pterygopalatine, trigeminal and superior ganglions prior to or simultaneously with their detection in the CNS. The antigens and nucleic acids were also observed in the olfactory bulb from an early stage of the infection. In the spinal cord, virus-infected cells were first demonstrated in the grey matter of the thoracic cord. The virus, which primarily replicated in the lungs, was considered to invade the thoracic cord via cardiopulmonary splanchnic nerves and sympathetic nerves. These findings indicate that the virus reached the CNS through afferent fibers of the olfactory, vagal, trigeminal, and sympathetic nerves following replication in the respiratory mucosa.