Selection, identification and crystal structure of shark-derived single-domain antibodies against a green fluorescent protein.

Shark variable domain of new antigen receptors (VNARs) are the smallest naturally occurring binding domains with properties of low complexity, small size, cytoplasmic expression, and ease of engineering. Green fluorescent protein (GFP) molecules have been analyzed in conventional microscopy, but their spectral characteristics preclude their use in techniques offering substantially higher resolution. Besides, the GFP molecules can be quenched in acidic environment, which makes it necessary to develop anti-GFP antibody to solve these problems. In view of the diverse applications of GFP and unique physicochemical features of VNAR, the present study aims to generate VNARs against GFP. Here, we identified 36 VNARs targeting eCGP123, an extremely stable GFP, by phage display from three immunized sharks. These VNARs bound to eCGP123 with affinity constant KD values ranging from 6.76 to 605 nM. Among them, two lead VNARs named aGFP-14 and aGFP-15 with nanomolar eCGP123-binding affinity were selected for in-depth characterization. aGFP-14 and aGFP-15 recognized similar epitopes on eCGP123. X-ray crystallography studies clarified the mechanism by which aGFP14 interacts with eCGP123. aGFP-14 also showed cross-reaction with EGFP, with KD values of 47.2 nM. Finally, immunostaining analyses demonstrated that aGFP-14 was able to bind effectively to the EGFP expressed in both cultured cells and mouse brain tissues, and can be used as a fluorescence amplifier for EGFP. Our research demonstrates a feasible idea for the screening and production of shark-derived VNARs. The two high-affinity VNARs developed in the study contribute to the diversity of GFP sdAbs and may enhance the applications of GFP.

Diagnostic possibility of the combination of exhaled nitric oxide and blood eosinophil count for eosinophilic asthma.

BACKGROUND: Tests to identify reversible airflow limitation are important in asthma diagnosis, but they are time-consuming and it may be difficult for patients to cooperate. We aimed to evaluate whether the combination of fractional exhaled nitric oxide (FeNO) and blood eosinophil (B-Eos) can be used to distinguish some asthma patients who could avoid objective tests. METHODS: We conducted a retrospective cohort study on 7463 suspected asthma cases between January 2014 and December 2019 in Chongqing, China, and identified 2349 patients with complete FeNO, B-Eos count, and spirometry data. Asthma was diagnosed by clinicians by the criteria of recurrent respiratory symptoms and a positive bronchial-provocation or bronchodilation test (BPT, BPD). We evaluated the diagnostic accuracy of FeNO or B-Eos alone or both in combination for asthma using receiver operating characteristic (ROC) curve analysis. RESULTS: In this study, 824 patients were diagnosed with asthma. When FeNO and B-Eos counts were used in combination, the area under the ROC curve (AUC) for diagnosing asthma increased slightly (0.768 vs. 0.745 [FeNO] or 0.728 [B-Eos]; both P < 0.001). The odds ratio for having asthma increased progressively with a gradual increase in FeNO or B-Eos count (both P < 0.001; assessed using the Cochran-Armitage trend test). Further analysis of in-series combinations of different threshold values for these biomarkers indicated that moderately elevated biomarker levels (FeNO > 40 ppb and B-Eos > 300 cells/µl) support a diagnosis of asthma because diagnostic specificity was > 95% and the positive likelihood ratio (PLR) was > 10. This conclusion was verified when selecting the 2017-2019 data as the internal validation dataset. CONCLUSION: FeNO or B-Eos count alone is insufficient to accurately diagnose asthma. Patients with moderately elevated biomarkers (FeNO > 40 ppb and B-Eos > 300 cells/µl) could be diagnosed with asthma and avoid objective tests when such tests are not feasible.

Successful transurethral resection of the prostate in ectopic prostate pheochromocytoma: A case report.

INTRODUCTION: Most pheochromocytomas of the urinary tract are located in the bladder. However, ectopic prostate pheochromocytomas have rarely been reported. We herein report an unusual case of ectopic prostate pheochromocytoma successfully treated by transurethral resection of the prostate (TURP). PATIENT CONCERNS: A 44-year-old Asian man with no significant previous medical history such as hypertension, presented to the urologist complaining of palpitations and anxiety on urination for more than 1 month. DIAGNOSES: Pathological examination confirmed ectopic prostate pheochromocytoma. INTERVENTIONS: An ectopic prostate pheochromocytoma without definite metastasis was confirmed. The lesion was successfully treated via TURP. OUTCOMES: All of his symptoms completely and immediately disappeared after surgery. Over a 21-month follow-up period, a repeat abdominal computed tomography (CT) scan did not show any evidence of recurrence. CONCLUSION: When patients present with symptoms of catecholamine excess on urination, extra-adrenal pheochromocytoma in the prostate should also be considered. TURP may be a viable option for therapy.

Bladder leiomyoma presenting as dyspareunia: Case report and literature review.

INTRODUCTION: Leiomyoma of the bladder is a rare tumor arising from the submucosa. Most patients with bladder leiomyoma may present with urinary frequency or obstructive urinary symptoms. However, there are a few cases of bladder leiomyoma coexisting with uterine leiomyoma presenting as dyspareunia. We herein report an unusual case of coexisting bladder leiomyoma and uterine leiomyoma presenting as dyspareunia. CASE PRESENTATION: A 44-year-old Asian female presented to urologist and complained that she had experienced dyspareunia over the preceding several months. A pelvic ultrasonography revealed a mass lesion located in the trigone of urinary bladder. The mass lesion was confirmed on contrast-enhanced computed tomography (CT). The CT scan also revealed a lobulated and enlarged uterus consistent with uterine leiomyoma. Then, the biopsies were then taken with a transurethral resection (TUR) loop and these biopsies showed a benign proliferation of smooth muscle in a connective tissue stroma suggestive of bladder leiomyoma. An open local excision of bladder leiomyoma and hysteromyomectomy were performed successfully. Histological examination confirmed bladder leiomyoma coexisting with uterine leiomyoma. CONCLUSION: This case highlights a rare presentation of bladder leiomyoma, dyspareunia, as the chief symptom in a patient who had coexisting uterine leiomyoma. Bladder leiomyomas coexisting with uterine leiomyomas are rare and can present with a wide spectrum of complaints including without symptoms, irritative symptoms, obstructive symptoms, or even dyspareunia.

Multinodular Goiter Spontaneous Hemorrhage in ESRD Patients Result in Acute Respiratory Failure: A Case Report.

Euthyroid multinodular goiters may lead to acute respiratory failure caused by airway obstruction or laryngotracheal compression. Here, we present a case admitted to the nephrologist with multinodular goiter spontaneous hemorrhage along with respiratory failure and end-stage renal disease (ESRD), which required urgent surgical intervention.We report the case of a 63-year-old woman with ESRD who presented with a rapidly enlarging nodular goiter resulting in acute respiratory failure. Endotracheal intubation and emergency partial thyroidectomy were performed, revealing multinodular goiter spontaneous hemorrhage by postoperative histopathology. Several cases of benign goiters necessitating endotracheal intubation have been reported. Goiters are among the rare diagnoses in patients consulting at our institution's Nephrology.This case illustrates that ESRD patients with benign goiter may lead to acute respiratory failure due to airway obstruction or laryngotracheal compression. It was found in agreement with previous reports. This case highlights that ESRD patient at risk of this life threatening complication such as multinodular goiter hemorrhage should be managed with elective thyroidectomy to reduce morbidity and mortality.

IgG4-related Kidney Disease Mimicking Malignant Ureter Tumor: Case Report and Literature Review.

Immunoglobulin G4-related disease is a recently recognized systemic disease that can affect any organ or tissue in the body, including the kidneys. IgG4-related kidney disease (IgG4-RKD) is an important part of immunoglobulin G4-related disease. The most common renal manifestation of IgG4-RKD is tubulointerstitial nephritis and glomerular lesions. There, however, is few case of IgG4-RKD mimicking malignant ureter tumor leading to severe hydronephrosis. We herein report an unusual case of IgG4-RKD mimicking malignancy.A 66-year-old Asian man presented to the nephrologist with soreness of loins, anorexia, and acute kidney injury in 2010. His renal function spontaneously improved after 2 weeks' hemodialysis without systemic steroid therapy. Four years later, he presented to the urologist with severe left hydronephrosis because of marked thickness of the left ureter wall. As a ureteral malignancy could not be ruled out, laparoscopic nephroureterectomy was performed.IgG4-related kidney disease was confirmed by the histologic examination. Then, repeat laboratory test showed almost complete recovery of renal function after initiation of steroidal therapy.This case highlights the rare possibility of IgG4-RKD mimicking malignant ureter tumor. Nephrologist and pathologists should be aware of the possibility that hydronephrosis with ureter obstruction may be involved in IgG4-RKD.

Tubulointerstitial Nephritis and Uveitis Syndrome in an Elderly Man: Case Report and Literature Review.

Tubulointerstitial nephritis and uveitis (TINU) syndrome is a rare disease of unknown etiology defined by the combination of tubulointerstitial nephritis, uveitis, and biochemical abnormalities. It has been reported that TINU mainly affects adolescents and young women. Here we reported a special case regarding a 60-year-old man with acute renal failure due to TINU syndrome documented by renal biopsy.We present a rare case of an elderly patient, who had been suffering from a fever for 2 weeks, characterized by sudden onset and resolving spontaneously, and accompanied by extreme fatigue, loss of appetite, and shivering. Renal biopsy showed a tubulointerstitial nephritis, with polymorphonuclear infiltration and acute tubulitis. In the outpatient clinic, he was diagnosed with idiopathic bilateral anterior uveitis 1 month ago. Ophthalmological examination revealed anterior asymptomatic bilateral uveitis. Human leukocyte antigen (HLA) typing (HLA-DQA1*0101/0201 and HLA-DQB1*0303/0503) was found which supported the suspect of TINU syndrome. The patient was treated with oral prednisone (1 mg/kg) and continued for 8 weeks on tapering doses. Serum creatinine normalized within 3 and 6 months later renal function also recovered completely.This case highlights that TINU syndrome is probably an underdiagnosed disease responsible for some cases of idiopathic anterior uveitis in elderly male patients. It is of critical importance to be aware of this syndrome by nephrologist and ophthalmologists in this special population. Further studies are needed to elucidate clinical characteristic and pathogenesis of TINU syndrome in elderly population.