Amylase intrapancreatic infusion delays insulin release during an intravenous glucose tolerance test,proof of acini–islet–acinar interactions

BACKGROUND The possible existence of an acini–islet–acinar(AIA)reflex,involving mutual amylase and insulin interactions,was investigated in the current acute experiment on pigs.AIM To confirm the existence of an AIA reflex and justify the placement of the exocrine and endocrine pancreatic components within the same organ.METHODS The study was performed on six pigs under general anesthesia.An intravenous glucose tolerance test was performed,with a bolus infusion of 50%glucose to the jugular vein,while amylase(5000 U/kg)or vehicle intrapancreatic infusions were administered via the pancreaticoduodenalis cranialis artery during 30 min with a 1 mL/min flow rate.RESULTS The amylase infusion to pancreatic arterial circulation inhibited and delayed the insulin release peak which is usually associated with the highest value of blood glucose and is typically observed at 15 min after glucose infusion,for>1 h.The intrapancreatic infusion of the vehicle(saline)did not have any effect on the time frame of insulin release.Infusion of 1%bovine serum albumin changed the insulin release curve dramatically and prolonged the high range of insulin secretion,far beyond the glucose peak.CONCLUSION Intrapancreatic arterial infusion of amylase interrupted the integrated glucose–insulin interactions.This confirms an AIA reflex and justifies placement of the exocrine and endocrine pancreatic components within the same organ.

Special features of SARS-CoV-2 in daily practice

The severe acute respiratory syndrome-coronavirus-2(commonly known as SARS-CoV-2)is a novel coronavirus(designated as 2019-nCoV),which was isolated for the first time after the Chinese health authorities reported a cluster of pneumonia cases in Wuhan,China in December 2019.Optimal management of the Coronavirus Disease-2019 disease is evolving quickly and treatment guidelines,based on scientific evidence and experts’opinions with clinical experience,are constantly being updated.On January 30,2020,the World Health Organization declared the SARS-CoV-2 outbreak as a"Public Health Emergency of International Concern".The total lack of immune protection brought about a severe spread of the contagion all over the world.For this reason,diagnostic tools,patient management and therapeutic approaches have been tested along the way,in the desperate race to break free from the widespread infection and its fatal respiratory complications.Current medical knowledge and research on severe and critical patients’management and experimental treatments are still evolving,but several protocols on minimizing risk of infection among the general population,patients and healthcare workers have been approved and diffused by International Health Authorities.

Ectomesenchymal chondromyxoid tumor: a comprehensive updated review of the literature and case report

Prompted by a unique case of an ectomesenchymal chondromyxoid tumor(ECT) of the palate in a 54-year-old female, we reviewed the English and German literature on this entity until the end of 2016 using Pub Med. The search produced 74 lingual cases with a nearly equal sex distribution and a mean age of 39.3 years, and two extra-lingual cases sharing histological and immunohistological features including nodular growth, round, fusiform or spindle-shaped cellular architecture, and chondromyxoid stroma.Immunophenotyping showed the majority of cases to be positive for glial fibrillary acidic protein(GFAP), S-100 protein,glycoprotein CD57, pancytokeratin (AE1/AE3), and smooth muscle actin(SMA); in isolated cases there was molecular-genetic rearrangement or gain of Ewing sarcoma breakpoint region 1 (EWSR1) but no rearrangement of pleomorphic adenoma gene 1 (PLAG1). At present, ectomesenchymal cells that migrate from the neural crest are considered to play a pivotal role in tumor origin.All cases had a benign course, although there were three recurrences. Because of the rarity of this tumor and the need for differential diagnostic differentiation from myoepithelioma and pleomorphic adenoma, both oral surgeons and pathologists should be aware of this entity.

Second premolar agenesis is associated with mandibular form： a geometric morphometric analysis of mandibular cross-sections

The aim of this study was to compare mandibular form （i.e., size and shape） between patients with agenesis of the lower second premolar （P2） and a control group with no agenesis. Three hypotheses were tested： （H1） agenesis causes a change in mandibular morphology because of inadequate alveolar ridge development in the area of the missing tooth （mandibular plasticity）; （H2） agenesis is caused by spatial limitations within the mandible （dental plasticity）; and （H3） common genetic/ epigenetic factors cause agenesis and affect mandibular form （pleiotropy）. A geometric morphometric analysis was applied to cross-sectional images of computed tomography （CT） scans of three matched groups （n= 50 each）： （1） regularly erupted P2; （2） agenesis of P2 and the primary second molar in situ; and （3） agenesis of P2 and the primary second molar missing for 〉3 months. Cross-sections of the three areas of interest （first premolar, P2, first molar） were digitized with 23 landmarks and superimposed by a generalized Procrustes analysis. On average, the mandibular cross-sections were narrower and shorter in patients with P2 agenesis compared with that in the control group. Both agenesis groups featured a pronounced submandibular fossa. These differences extended at least one tooth beyond the agenesis-affected region. Taken together with the large interindividual variation that resulted in massively overlapping group distributions, these findings support genetic and/or epigenetic pleiotropy （H3） as the most likely origin of the observed covariation between mandibular form and odontogenesis. Clinically, reduced dimensions and greater variability of mandibular form, as well as a pronounced submandibular fossa, should be expected during the treatment planning of patients with P2 agenesis.

Implant Placement in a Cemento-Osseous Dysplasia:A case report

We present a 45-year-old black woman diagnosed with a florid cemento-osseous dysplasia(FCOD)affecting the right lower quadrant and the anterior mandibular region.The patient requested dental implants to rehabilitate the edentulous central lower incisors area(teeth#31 and#41)corresponding to a periapical cemento-osseous dysplasia(PCOD).Successful osseointegration of the two implants was obtained using a two-step procedure in order to limit the risk of complications associated with implant placement.Follow-up at one year showed no recurrence and good implant stability.Due to the abnormal quality of the bone in cemento-osseous dysplasia(COD),implant placement is generally avoided,and no other case reports have been reported in the literature in patients affected by PCOD.The present case suggests that in an appropriate clinical setting,implant placement may be a successful procedure.