[Screening and preliminary validation of biomarkers in sputum-negative pulmonary tuberculosis based on positron emission tomography/computed tomography and transcriptomics]

Objective: To screen and perform preliminary clinical validation of biomarkers of activity based on positron emission tomography/computed tomography (PET-CT) and transcriptomics in sputum-negative pulmonary tuberculosis lesion tissue. Methods: Nine patients with sputum-negative pulmonary tuberculosis treated surgically at the Shanghai Public Health Clinical Center for Thoracic Surgery from January 1, 2017 to December 31, 2019 were retrospectively collected as the discovery group, including four males and five females, aged 20-57 years (mean 36 years). All of the patients underwent PET-CT scanning before surgery, and the resected specimens were postoperatively classified according to preoperative PET-CT. The resected specimens were divided into areas with increased fluorodeoxyglucose (FDG) metabolism (SUVmax>3) and areas with normal FDG metabolism (SUVmax ≤ 3) according to the preoperative PET-CT performance. After sample processing, total RNA was extracted from the tissues of different regions, and then whole gene transcriptome sequencing was performed. Bioinformatics analysis of the two sets of data was performed to discover the expression profiles of the differences in whole gene transcriptome data between the two regions and to screen for candidate biomarkers. Eighty patients with sputum-negative pulmonary tuberculosis admitted to Shanghai Public Health Clinical Center from January 1, 2019 to January 1, 2021 were retrospectively collected as the validation group, including 37 males and 43 females, aged 20-62 years, with an average age of 39 years. The validation group was divided into a group with increased SUV (n=40) and a group without lesions on CT imaging (n=40). Enzyme-linked immunosorbent assay (ELISA) was used to determine the protein levels of candidate biomarkers in the peripheral plasma of patients. The effect of biomarkers was assessed using subject operating characteristic (ROC) curves. Student's t-test was used to determine whether the difference in protein levels between the two groups was statistically significant. Results: Bioinformatics analysis revealed that the expression levels of C1QB, CCL19, CCL5 and HLA-DMB correlated with the metabolic activity of sputum-negative tuberculosis lesion tissue. Further screening and validation by the validation group confirmed that the difference in C1QB protein levels in the peripheral plasma of patients was statistically significant between the group with increased SUV and the group without lesions on CT imaging [(3.55±0.34) mg/L vs. (2.75±0.21) mg/L, t=4.12, P<0.001]. And the ROC curve showed that the area under the curve for C1QB protein levels was 0.731, which had potential clinical value. Conclusion: The C1QB protein level can be used to assess the activity of lesions in patients with sputum-negative tuberculosis and is a potential biomarker.

Efficacy and safety of lubiprostone for the treatment of functional constipation in Chinese adult patients: A multicenter, randomized, double-blind, placebo-controlled trial

OBJECTIVES

Functional constipation is a gastrointestinal disorder prevalent around the world. Lubiprostone is the first locally acting type-2 chloride channel activator to be used for treating constipation. This study aimed to evaluate the efficacy and safety of lubiprostone in Chinese adults with functional constipation.

METHODS

This was a multicenter, randomized, double-blind, placebo-controlled study. Patients with functional constipation were randomized to receive either lubiprostone (24 mcg twice daily) or placebo for 4 weeks. The primary end-point was the frequency of spontaneous bowel movements (SBMs) during the first week of treatment. The secondary end-points included the median time of the first SBM, SBM frequency at weeks 2, 3 and 4, weekly response rate of SBMs, the stool consistency score and average number of complete spontaneous bowel movements (CSBMs) per week.

RESULTS

In total, 259 patients were randomized, with 130 in the lubiprostone group and 129 in the placebo group. SBM frequency was higher in the lubiprostone group (4.88 ± 4.09/wk) than that in the placebo group (3.22 ± 2.01/wk) at week 1 (P < 0.0001). SBM frequency was also higher in the lubiprostone group at weeks 2, 3 and 4. The average number of CSBMs and the stool consistency score in the lubiprostone group were significantly higher than that in the placebo group at each week. No drug-related serious adverse events (AEs) occurred. The most commonly reported AE was nausea.

CONCLUSION

Lubiprostone was superior to placebo in treating Chinese patients with functional constipation, together with good safety profile.

[IgG4-related lung disease: analysis of 8 cases and literature review]

Objective: To improve the understanding and treatment of IgG4-related lung disease (IgG4-RLD). Methods: The clinical characteristics, serum IgG4 levels, pathological features, chest CT, therapy and prognosis of 8 patients with IgG4-RLD were retrospectively analyzed. These patients were admitted to the People's Liberation Army General Hospital and the pathological diagnosis was made between December 2005 and March 2016. Relevant literatures were reviewed. Results: The 8 patients with IgG4-RLD included 4 men and 4 women, with an average age of (59±4) years (range, 37-74). The respiratory symptoms included shortness of breath, cough, and expectoration. Extra-pulmonary symptoms included abdominal pain, facial edema, and fever. Extrapulmonary organs were involved in 7 cases. Serum IgG4 levels were elevated in 8 cases, with an average concentration of(17±6)g/L. Chest CT showed solid lung nodules in 6, alveolar-interstitial infiltration in 5, bronchovascular lesions in 3 and ground glass shadows in 2 cases. PET/CT was performed in 2 cases and it showed multiple organ involvement with higher radioactivity uptake(SUVmax2.9-4.2). The pathological examination found lymphocyte and plasma cell infiltration in 7, fibrous tissue hyperplasia in 5, and occlusive vasculitis in 2 cases. On immunohistochemical staining, the ratio of IgG4-positive plasma cells to IgG-positive plasma cells was higher than 40%in 3 cases. The number of IgG4-positive plasma cells was 10-50/HP in 8 cases. The misdiagnosis rate was 100% before the final diagnosis was made. Three cases received glucocorticoids with immunosuppressant therapy, 2 received surgery combined with glucocorticoid therapy, 2 received glucocorticoid therapy alone, and 1 only received surgery. The follow-up time was 4-132 months, with remission in 7 cases, and disease progression in 1 case, but no death. A total of 195 cases of IgG4-RLD were reviewed from the literature, among whom 111 cases were admitted with respiratory symptoms, 144 with extra-pulmonary involvement. Serum IgG4 levels were detected in 179 cases, with an average concentration of 5.408 g/L. The nodular type was predominant, accounting for 36.9%. Of these cases, 178 received glucocorticoid treatment with disease remission. Conclusions: The major clinical manifestations of IgG4-RLD were shortness of breath, cough and expectoration. Multiple organ lesions were common. The misdiagnosis rate was extremely high. The diagnosis could be made based on pathological features and IgG4 serum levels . Glucocorticoid treatment was effective.

Emergence of a coronavirus infectious bronchitis virus mutant with a truncated 3b gene: functional characterization of the 3b protein in pathogenesis and replication

The subgenomic RNA 3 of IBV has been shown to be a tricistronic mRNA, encoding three products in IBV-infected cells. To explore if the least expressed ORF, ORF 3b, which encodes a nonstructural protein, is evolutionarily conserved and functionally indispensable for viral propagation in cultured cells, the Beaudette strain of IBV was propagated in chicken embryonated eggs for three passages and then adapted to a monkey kidney cell line, Vero. The 3b gene of passage 3 in embryonated eggs and passages 7, 15, 20, 25, 30, 35 50, and 65 in Vero cells were amplified by reverse transcription-polymerase chain reaction and sequenced. The results showed that viral RNA extracted from passages 35, 50, and 65 contained a single A insertion in a 6A stretch of the 3b gene between nucleotides 24075 and 24080, whereas the early passages carried the normal 3b gene. This insertion resulted in a frameshift event and therefore, if expressed, a C-terminally truncated protein. We showed that the frameshifting product, cloned in a plasmid, was expressed in vitro and in cells transfected with the mutant construct. The normal product of the 3b gene is 64 amino acids long, whereas the frameshifting product is 34 amino acids long with only 17 homogeneous amino acid residues at the N-terminal half. Immunofluorescent studies revealed that the normal 3b protein was localized to the nucleus and the truncated product showed a "free" distribution pattern, indicating that the C-terminal portion of 3b was responsible for its nuclear localization. Comparison of the complete genome sequences (27.6 kb) of isolates p20c22 and p36c12 (from passages 20 and 36, respectively) revealed that p36c12 contains three amino acid substitutions, two in the 195-kDa protein (encoded by gene 1) and one in the S protein, in addition to the frameshifting 3b product. Further characterization of the two isolates demonstrated that p36c12 showed growth advantage over p20c22 in both Vero cells and chicken embryos and was more virulent in chicken embryos than p20c22. These results suggest that the 3b gene product is not essential for the replication of IBV.

Diphtheria toxin-related alpha-melanocyte-stimulating hormone fusion toxin. Internal in-frame deletion from Thr387 to His485 results in the formation of a highly potent fusion toxin which is resistant to proteolytic degradation

We have previously reported the genetic construction and properties of a fusion protein which was composed of the enzymatically active and membrane translocation domains of the diphtheria toxin and the receptor-specific ligand alpha-melanocyte-stimulating hormone (alpha-MSH) (Murphy, J.R., Bishai, W., Borowski, M., Miyanohara, A., Boyd, J., and Nagle, S. (1986) Proc. Natl. Acad. Sci. U.S.A. 83, 8258-8262). While this fusion toxin was found to be selectively toxic for MSH receptor-bearing cells in vitro, it was subject to profound proteolytic degradation in recombinant Escherichia coli making purification difficult. We now report that the deletion of diphtheria toxin fragment B sequences between Thr387 and His485 results in a protease-resistant form of the fusion toxin, DAB389-alpha-MSH. We show that DAB389-alpha-MSH is expressed in high yield in recombinant Escherichia coli, that it is readily purified from crude bacterial lysates by immunoaffinity and high performance liquid chromatography, and its cytotoxic activity toward both human and murine malignant melanoma cell lines is mediated through the MSH receptor.

[Carcinoid of ectopic pancreas tissue--islet cell tumor]

A case of islet cell tumor--carcinoid of the ectopic pancreas is reported. The patient had been operated six times because of recurrent abdominal tumor mass and intermittent hypoglycemic coma. The first five operations were done with the diagnosis of mesotheliosarcoma by pathology. The last operation was done in our hospital with the final diagnosis of carcinoid--islet cell tumor. In addition to the light microscopic view, several diagnostic features were observed as follows: Under electron microscopy, membrane bound secretive granules were present in the tumor cytoplasm. Neither brush-like microvilli nor lumen formation of the mesothelioma were found. By immunohistochemistry, positive granules to immunoperoxidase stain of insulin were observed in some tumor cytoplasm. By laboratory test, levels of blood 5-hydroxytryptamine and urinary 5-hydroxyindolacetic acid were elevated. Sometimes it is difficult to differentiate carcinoid from islet cell tumor only by morphology, because both are derived from the same origin during the embryonic development which is probably related to the endocrine system from the embryonic foregut. The latter arises from the neuro-ectoderm and belongs to APUD system.