Mesenchymal Stem Cell Extracellular Vesicles from TissueMimetic System Enhance Epidermal Regeneration via Formation of Migratory Cell Sheets

BACKGROUND@#The secretome of adipose-derived mesenchymal stem cells (ASCs) offers a unique approach to understanding and treating wounds, including the critical process of epidermal regeneration orchestrated by keratinocytes.However, 2D culture techniques drastically alter the secretory dynamics of ASCs, which has led to ambiguity in understanding which secreted compounds (e.g., growth factors, exosomes, reactive oxygen species) may be driving epithelialization. @*METHODS@#A novel tissue-mimetic 3D hydrogel system was utilized to enhance the retainment of a more regenerative ASC phenotype and highlight the functional secretome differences between 2D and 3D. Subsequently, the ASC-secretome was stratified by molecular weight and the presence/absence of extracellular vesicles (EVs). The ASC-secretome fractions were then evaluated to assess for the capacity to augment specific keratinocyte activities. @*RESULTS@#Culture of ASCs within the tissue-mimetic system enhanced protein secretion * 50%, exclusively coming from the [ 100 kDa fraction. The ASC-secretome ability to modulate epithelialization functions, including migration, proliferation, differentiation, and morphology, resided within the ‘‘[ 100 kDa’’ fraction, with the 3D ASC-secretome providing the greatest improvement. 3D ASC EV secretion was enhanced two-fold and exhibited dose-dependent effects on epidermal regeneration. Notably, ASC-EVs induced morphological changes in keratinocytes reminiscent of native regeneration, including formation of stratified cell sheets. However, only 3D-EVs promoted collective cell sheet migration and an epithelial-to-mesenchymal-like transition in keratinocytes, whereas 2D-EVs contained an anti-migratory stimulus. @*CONCLUSION@#This study demonstrates how critical the culture environment is on influencing ASC-secretome regenerative capabilities. Additionally, the critical role of EVs in modulating epidermal regeneration is revealed and their translatability for future clinical therapies is discussed.

A Pilot Study of Fluorodeoxyglucose Positron Emission Tomography Findings in Patients with Phenylketonuria before and during Sapropterin Supplementation

BACKGROUND AND PURPOSE: PET scanning with fluorodeoxyglucose (FDG-PET) is a non-invasive method that measures regional glucose metabolic rate. Phenylalanine (Phe) and its metabolites appear to impair several aspects of brain energy metabolism. 1) To evaluate brain glucose metabolism with FDG-PET imaging in phenylketonuria (PKU) patients before and 4 months after sapropterin therapy; 2) to evaluate neurodevelopmental changes, blood Phe levels and dietary Phe tolerance before and after sapropterin therapy; 3) to generate pilot data to assess the feasibility of evaluating brain glucose metabolism with FDG-PET imaging and to explore potential trends resulting from the administration of sapropterin therapy. METHODS: We enrolled 5 subjects, ranged in age from 22 years to 51 years, with PKU. Subjects underwent FDG-PET brain imaging, blood tests for Phe and tyrosine levels, and neurocognitive evaluations before and 4 months after sapropterin therapy (20 mg/kg/day). All subjects' Phe and tyrosine levels were monitored once a week during the study. Subjects kept 3 day diet records that allow calculation of Phe intake. RESULTS: None of the subjects responded to sapropterin therapy based on 30% decrease in blood Phe level. The data show that glucose metabolism appeared depressed in the cerebellum and left parietal cortex while it was increased in the frontal and anterior cingulate cortices in all five subjects. In response to sapropterin therapy, relative glucose metabolism showed significant increases in left Broca's and right superior lateral temporal cortices. Interestingly, there was corresponding enhanced performance in a phonemic fluency test performed during pre- and postneurocognitive evaluation. CONCLUSIONS: Further studies with a larger sample size are needed to confirm the above changes in both sapropterin non-responsive and responsive PKU patients.

CA 19-9 to differentiate benign and malignant masses in chronic pancreatitis: is there any benefit.

Background The role of the tumor marker CA 19-9 in differentiating benign from malignant masses in chronic pancreatitis has not been extensively studied. Aim This study aims at assessing the accuracy of CA 19-9 in differentiating infl ammatory head masses in chronic pancreatitis from superimposed carcinomas on chronic pancreatitis. Methods The data of 84 consecutive patients who had mass lesions in chronic pancreatitis were analyzed to determine the sensitivity, specifi city and predictive values at cut-off values of 37, 100, 200 and 300 U/mL. Receiver operating characteristic (ROC) curves were used to assess the sensitivity and specifi city. Results There were 50 benign masses and 34 malignancies. The overall sensitivity and specifi city of CA 19-9 for cancer was 68% and 70%, respectively. There was a higher positivity of CA 19-9 in cancers than in benign masses (23/34; 68% versus 15/50; 30%, P<0.01) with cut-off values of 37 U/mL. Higher positivity rates were obtained in cancers using other cut-off values such as 100, 200 and 300 U/mL. Values over 300 U/mL were 100% specifi c for malignancy, but occurred in only 5 (of whom had distant metastases) of 34 patients. Conclusion CA 19-9 level in excess of 300 U/mL in mass lesions in chronic pancreatitis was always indicative of malignancy.

Intussusception due to ileal metastases from renal cell carcinoma.

Small bowel secondaries from renal cell carcinoma are rare. Patients usually present with features of intestinal obstruction or GI bleeding. Management should be aggressive since metastasectomy can improve the quality of life and survival.

Multidisciplinary approach in the long-term management of intrahepatic stones: Indian experience.

BACKGROUND: Intrahepatic stones, though common in East Asia, are uncommon in India. There is paucity of data from India regarding the treatment and long-term outcome of patients with intrahepatic stones. METHODS: We retrospectively analyzed medical records of 35 patients with intrahepatic stones who had been treated surgically. Endoscopic biliary drainage had been used in patients who presented with acute cholangitis. Intraoperative stone clearance was confirmed by choledochoscopy and intraoperative cholangiography. Outcome of surgery, frequency and subsequent management of recurrent intrahepatic stones, and factors associated with stone recurrence and cholangitis were analyzed. RESULTS: Twenty-one (60%) patients had bilobar disease. Eight patients underwent hepatectomy and 16 hepatico-jejunostomy with access loop; 12 of these were jejuno-duodenal anastomoses. Postoperative morbidity was observed in 10 patients (29%). Recurrence of stones occurred in 12 patients (34%) and cholangitis in 9 patients (26%). Presence of bilobar disease and associated biliary strictures were associated with recurrent cholangitis (p< 0.05). Two patients (6%) required re-operation for recurrent cholangitis. Complete removal of recurrent stones using conventional endoscope was possible through jejuno-duodenostomy in all 5 cases who had this type of access loop construction. CONCLUSION: Surgical treatment for intrahepatic stones depends on the site of involvement. Construction of a jejuno-duodenal access loop in patients with bilobar disease and intrahepatic strictures is helpful in facilitating postoperative stone clearance. A multidisciplinary approach is beneficial especially when the disease is bilobar and recurrent in type.

Primary tuberculous stricture of the oesophagus mimicking carcinoma.

A middle-aged woman presented with progressive dysphagia and weight loss was investigated. A stricture involving the lower third of oesophagus was identified but precise histology of the lesion could not be obtained even after multiple biopsies. The resected specimen showed histology consistent with oesophageal tuberculosis.