The risk of transmission of the novel coronavirus (SARS-CoV-2) with human heart valve transplantation: evaluation of cardio-vascular tissues from two consecutive heart donors with asymptomatic COVID-19.

We report on two living donors of explanted hearts while receiving heart transplantation that tested positive for SARS-CoV-2 on the day of donation, although clinically asymptomatic. They underwent heart transplantation for ischaemic and hypertrophic obstructive cardiomyopathy, respectively. After evaluation of donor hearts, we cryopreserved and stored two pulmonary valves for clinical application and one aortic valve for research. Light microscopy of myocardium, mitral valve and aortic and pulmonary arterial wall and RT-PCR SARS-CoV-2 test of myocardium, mitral and tricuspid valve and aortic wall for detection of SARS-CoV-2 were performed. Presence of ACE2 in tissues was assessed with immunostaining. Light microscopy revealed a mild eosinophilic myocarditis in the ischemic cardiomyopathy heart, whereas enlarged cardiomyocytes with irregular nucleus and some with cytoplasmic vacuoles in the hypertrophic obstructive cardiomyopathy heart. Aortic and pulmonary wall were histologically normal. Immunostaining revealed diffuse presence of ACE2 in the myocardium of the heart with eosinophilic myocarditis, but only discrete presence in the hypertrophic cardiomyopathy heart. The RT-PCR SARS-CoV-2 test showed no presence of the virus in tested tissues. Despite eosinophilic myocarditis in the ischemic cardiomyopathy heart, no viral traces were found in the myocardium and valve tissues. However, ACE2 was present diffusely in the ischemic cardiomyopathy heart. SARS-CoV-2 could not be detected in the cardiac tissues of these COVID-19 asymptomatic heart donors. In our opinion, clinical application of the valves from these donors presents negligible risk for coronavirus transmission. Nonetheless, considering the uncertainty regarding the risk of virus transmission with the human tissue transplantation, we would not release in any case the pulmonary valve recovered from the eosinophilic myocarditis heart. In contrast, we may consider the release of the pulmonary valve from the dilated cardiomyopathy heart only for a life-threatening situation when no other similar allograft were available.

Epidemiological study of p53 tumor suppressor gene mutations in patients from Luxembourg and the German Saar region with an advanced colorectal cancer using PCR-SSCP analysis.

Mutations in the p53 tumor suppressor gene are usually associated with an advanced development of colorectal cancer characterized by the transition from the adenoma to the carcinoma stage. We used the polymerase chain reaction (PCR) followed by single-strand conformation polymorphism (SSCP) analysis to screen for the presence of mutations in the p53 gene of patients from Luxembourg and the German Saar region with colorectal cancers at various developmental stages. While we detected no mutations in 16 colic polypi at an early to intermediate stage (adenoma), we revealed seven (13.7%) non-silent point mutations (transitions) in exons 5 to 9 of the p53 gene in 51 colorectal tumors at a late stage (carcinoma). In addition to confirming previous observations, these results show that PCR-SSCP analysis can provide both a sensitive and rapid method for the genetic determination of the histopathological stage of colorectal samples.

Splice variants of the Drosophila PS2 integrins differentially interact with RGD-containing fragments of the extracellular proteins tiggrin, ten-m, and D-laminin 2.

Two new potential ligands of the Drosophila PS2 integrins have been characterized by functional interaction in cell culture. These potential ligands are a new Drosophila laminin alpha2 chain encoded by the wing blister locus and Ten-m, an extracellular protein known to be involved in embryonic pattern formation. As with previously identified PS2 ligands, both contain RGD sequences, and RGD-containing fragments of these two proteins (DLAM-RGD and TENM-RGD) can support PS2 integrin-mediated cell spreading. In all cases, this spreading is inhibited specifically by short RGD-containing peptides. As previously found for the PS2 ligand tiggrin (and the tiggrin fragment TIG-RGD), TENM-RGD induces maximal spreading of cells expressing integrin containing the alphaPS2C splice variant. This is in contrast to DLAM-RGD, which is the first Drosophila polypeptide shown to interact preferentially with cells expressing the alphaPS2 m8 splice variant. The betaPS integrin subunit also varies in the presumed ligand binding region as a result of alternative splicing. For TIG-RGD and TENM-RGD, the beta splice variant has little effect, but for DLAM-RGD, maximal cell spreading is supported only by the betaPS4A form of the protein. Thus, the diversity in PS2 integrins due to splicing variations, in combination with diversity of matrix ligands, can greatly enhance the functional complexity of PS2-ligand interactions in the developing animal. The data also suggest that the splice variants may alter regions of the subunits that are directly involved in ligand interactions, and this is discussed with respect to models of integrin structure.

The PS2 integrin ligand tiggrin is required for proper muscle function in Drosophila.

Tiggrin is a novel extracellular matrix ligand for the Drosophila PS2 integrins. We have used flanking P elements to generate a precise deletion of tiggrin. Most flies lacking tiggrin die as larvae or pupae. A few adults do emerge and these appear to be relatively normal, displaying only misshapen abdomens and a low frequency of wing defects. Examination of larvae shows that muscle connections, function and morphology are defective in tiggrin mutants. Muscle contraction waves that extend the length of the larvae are much slower in tiggrin mutants. Direct examination of bodywall muscles shows defects in muscle attachment sites, where tiggrin is specifically localized, and muscles appear thinner. Transgenes expressing tiggrin are capable of rescuing tiggrin mutant phenotypes. Transgenes expressing a mutant tiggrin, whose Arg-Gly-Asp (RGD) integrin recognition sequence has been mutated to Leu-Gly-Ala (LGA) show much reduced, but significant, rescuing ability. Cell spreading assays detect no interactions of this mutant tiggrin with PS2 integrins. Therefore, while the RGD sequence is critical for PS2 interactions and full activity in the whole fly, the mutant tiggrin retains some function(s) that are probably mediated by interactions with other ECM molecules or cell surface receptors

[Congenital cystic dilatation of the common bile duct, anomaly of the biliopancreatic junction and cancer of the bile ducts]. / Dilatation kystique congénitale du cholédoque, anomalie de la jonction bilio-pancréatique et cancer des voies biliaires.

The choledochus and pancreatic duct ordinarily enter the duodenum either separately or via a common channel located in the duodenal wall. The usual maximal length of the common channel is approximately 0.5 cm. An anomalous junction of the pancreaticobiliary tract is defined by the presence of an unusually long common channel whose length is 1 cm or longer. During the last 8 years, we studied 9 cases of congenital dilatation of the bile duct. Besides the choledochal cyst, all patients had a common channel which measured 1.5 cm or longer. The mean age of patients (6 females, 3 males) was 36.5 years. Three patients had extrahepatic bile tract carcinoma. One patient, a 51-year old man, had gallbladder carcinoma without stones while the two other patients, a 43-year old woman and a 32-year old man, had carcinoma arising from the wall of the cystic dilatation. These two patients had undergone a simple internal drainage procedure 16 and 8 years before, respectively. Our study suggests that the anomalous junction of the pancreaticobiliary tract, an embryonic anomaly which allows the reflux of pancreatic juice into the bile duct and gallbladder, may be responsible for congenital bile duct dilatation and biliary tract carcinoma. Total excision of the cystic dilatation and the gallbladder with hepaticojejunostomy is the appropriate surgical treatment.

[An intramural hematoma of the small intestine, during anticoagulant therapy: radiological course. Concerning one case]. / Hématome intramural du grêle sous traitement anticoagulant: évolution radiologique. A propos d'un cas

The authors present a case of intramural hematoma of the small intestines during anticoagulant treatment. With reference to this case, they study the frequency, etiopathogenesis and anatomy of this hematoma and particularly look at the radiological manifestations. In this respect they distinguish three stages in the evolution. The first, when the straight X-ray of the abdomen and barium followthrough demonstrate an axial stenosis of the small intestines with dilation of the proximal loops; the second (between the 7th and 20th days) when the loop affected by the hematoma takes on a characteristic "palissade" or "spring" -like sausage appearance; finally the third (after the 3rd week), when only thickening of the haustrations persists with progressive return to normal. The radiological diagnosis is discussed, not only with intramural hematomas of the small intestines of other etiologies (traumatic, during pancreatitis, during disorders in hemostatis), but also with conditions giving rise to similar radiological pictures: malabsorption, inflammatory conditions, etc.

[A propos of 210 emergency endoscopies in upper digestive hemorrhage]. / A propos de 210 endoscopies en urgence dans les hémorragies digestives hautes

The authors report their experience of 210 fiber endoscopies carried out as an emergency for upper digestive hemorrhage. They emphasize the necessity of early examination and only consider here examinations carried out within 12 hours from the start of the hemorrhage. In 91.4 % of cases, a correct diagnosis was possible. More than 20% of the patients had at least two lesions liable to cause hemorrhage. In cirrhosis, esophageal varices were the cause of hemorrhage in only 50% of cases.

[Endoscopic resection of colonic polyps. A propos of 45 polypectomies]. / La résection endoscopique des polypes du colon A propos de 45 polypectomies

Endoscopic resection of polyps of the colon is, no doubt, a considerable therapeutic advance. It avoids surgical operation permits histological examination and makes simple biopsy unnecessary. It is indicated in the presence of pediculated polyps of a diameter or less than 3 cm, whatever the site of the polyp. Thus we were able to remove 45 polyps without complications. The method is not indicated in a large size polyp, sessile polyps or diffuse polyposis. The follow-up is still insufficient to assess : 1) the true risk of resection which can only be undertaken after long experience of colonoscopy ; 2) the frequency or recurrent adenomas. Endoscopic resection is at present the simplest method of detection and treatment of carcinoma in situ of the colon of which we observed four cases in our series. The problem of surgical reoperation is discussed.