Identification by mass spectrometry of glucosaminylphosphatidylglycerol, a phosphatidylglycerol derivative, produced by Pseudomonas aeruginosa.

RATIONALE: Pseudomonas aeruginosa is an opportunistic pathogen bacterium widely considered to be an excellent research model in several areas of molecular studies, namely genomics and proteomics. However, its lipid metabolism is still not totally decrypted. While it is known that this bacterium has the particularity to produce phosphatidylcholine, a lipid mainly found in eukaryotes, other singularities are still to be discovered. METHODS: P. aeruginosa was grown as planktonic cultures to the stationary state. Membrane pellets were collected and lipids were extracted using the Bligh and Dyer protocol. Lipid extracts were analyzed by Electrospray Ionization Mass Spectrometry (ESI-MS) using high-resolution mass spectrometer (LTQ Orbitrap Elite, Thermo Scientific) in the negative mode. MSn spectra were recorded both in the Orbitrap and in the ion trap analyzer (collision-induced dissociation (CID) or higher energy collision-induced dissociation (HCD) mode). RESULTS: We observed by mass spectrometry and thin layer chromatography that P. aeruginosa produced an unreferenced lipid in classical growth conditions. MS2 analysis of the unknown ion indicates that it is a phosphatidylglycerol derivative. The exact mass shift corresponds to glucosamine which is largely found in the metabolism of this bacterium. MS3 analysis of secondary ions allowed us to conclude that this lipid is a glucosaminylphosphatidylglycerol, a phosphatidylglycerol derivative containing a glucosamine substituted at C4. CONCLUSIONS: We show here that P. aeruginosa is able to produce glucosaminylphosphatidylglycerols via a probable esterification of phosphatidylglycerols by glucosamine.

Pseudomonas aeruginosa produces phosphatidyltris(hydroxymethyl)aminomethane and derivatives when grown in Tris-buffered medium.

For optimal growth of a microorganism, the pH of the culture medium should be set at an optimum value. For that reason, growth media require buffering agents. We show in this study that, when grown in a medium supplemented with tris(hydroxymethyl)aminomethane (Tris), Pseudomonas aeruginosa is able to use this organic compound to produce new phospholipids. We thus pointed out that phosphatidyltris(hydroxymethyl)aminomethane as well as diphosphatidyltris(hydroxymethyl)aminomethane was detected in membrane lipid extracts of bacteria grown in Tris-buffered medium. Moreover, the amounts of lysoglycerophospholipids in the lipidome of P. aeruginosa grown in Tris-buffered medium increased leading to the presence of lysophosphatidylglycerol and lysophosphatidyltris(hydroxymethyl)aminomethane as well as other lysophospholipid derivatives. Finally, we investigated the effect of the presence of these exogenous phospholipids on the susceptibility of P. aeruginosa to some antibiotics. We observed a decrease of the minimal inhibitory concentrations of different antibiotic families, i.e., fluoroquinolones, aminoglycosides, ß-lactams and polymyxins, proving the importance of the buffer choice for growth medium and its impact on the lipidome.

Multifocal malignant perivascular epithelioid cell tumor (PEComa) of the peritoneum: A case report.

INTRODUCTION AND IMPORTANCE: Neoplasms with perivascular epithelioid-cell differentiation (PEComa) are rare. We present a case of multifocal malignant PEComas arising in the peritoneum. CASE PRESENTATION: A 61-year-old woman presented with a painful abdominal mass that had progressed over the past year and recently increased in size. Pelvic magnetic resonance imaging (MRI) showed two masses: an 11-cm partially solid and cystic tumor, with moderate contrast uptake probably originating from the left ovary, and an 18-cm sized, intraperitoneal abdominal heterogeneous enhancing mass. Two nodules in the mesentery and the bladder peritoneum were discovered intraoperatively. The patient underwent Hudson's intervention with resection of the epiploic mass and the two nodules. Microscopic examination revealed a tumor proliferation of epithelioid clear cells with delicate vascular septae. Immunohistochemistry was positive for HMB45, MelanA and SMA. The final diagnosis of a malignant PEComa was retained. The patient developed two local peritoneal recurrences and died after 26 months of follow-up. CLINICAL DISCUSSION: Our case is original by its multifocal presentation being the seventh case of a multifocal malignant PEComa reported in the literature. PEComa's clinical presentation and radiographic appearance can often mimic a soft tissue clear cell sarcoma. CONCLUSION: Clinical and pathological correlations are mandatory to make a precise diagnosis and adapt the treatment of PEComas.

Ovarian ALK+ diffuse large B-cell lymphoma: a case report and a review of the literature.

Through this case presentation and a review of the literature, we aim to describe clinical and pathologic features and to distinguish the outcome of these tumors. A 25-year-old woman presented with pelvic pain and an iliac mass. Workup revealed a 53-mm cystic partitioned mass of the left ovary infiltrating the left sacrum. She underwent a left adnexectomy. Gross examination revealed a ruptured ovarian mass. When dissected, it showed grayish cerebroid aspects. Histologic examination revealed a malignant tumor proliferation of the diffuse large cells. An immunohistochemical analysis showed negative results for PLAP, αFP, ßHCG, CD117, CK20, and CD30. It also showed lack of B markers and T marker (CD3) and an expression of CD138 and anaplastic lymphoma kinase. The patient was treated by 6 cycles of CHOP chemotherapy and a pelvic radiotherapy. She presented with a 15-cm splenomegaly 26 months later and died of febrile neutropenia. Most patients follow an aggressive disease and are unlikely to respond to the standard.

An unusual clinical presentation of ocular trauma in a child.

To report an unusual clinical presentation of ocular trauma in a child. Observational case report used in this study. A 12 year-old previously healthy boy presented with decreased vision and corneal opacity in the right eye following a punch in the face three years earlier. At presentation, his vision in the right eye was counting fingers. Ophthalmologic examination of the right eye revealed paracentral Descemet's membrane detachment and slit-lamp examination showed corneal opacity occupying almost 80 % of the corneal surface. In addition, there was a corneal white liquid collection communicating with the anterior chamber. The contralateral eye was within normal limits. The patient underwent penetrating keratoplasty. Bacteriological cultures of the corneal liquid did not reveal the presence of germs. The post-operative course was uneventful, the graft was clear and there was no evidence of graft rejection or failure. Visual acuity in the operated eye was 5/10. At present, the patient is still being followed up. The authors believe that this case is unique since Descemet's membrane detachment with liquid collection and corneal opacification has never been reported in literature to date.

Preoperative Intralesional Bevacizumab Injection in Primary Pterygium in Tunisian Patients: A Randomized Controlled Prospective Study.

Purpose: To assess the efficacy and safety of a single preoperative intralesional bevacizumab injection as an adjuvant treatment before primary pterygium surgery. Methods: We conducted a randomized controlled interventional study from January 2019 to December 2020. The study included a total of 60 patients (60 eyes) with primary pterygium. We defined two groups of 30 patients each. Group A received an intralesional injection of bevacizumab (Avastin), 1 month before surgery (lesion excision and conjunctival autograft). Group B (control) had only the surgical treatment. Patients were followed up 7 days (D7), 1 month (M1), 3 months (M3), and 6 months (M6) postoperatively. Pre-, per-, and postoperatively, photographs of the lesions were taken, as well as a histopathological examination. The main outcome measures were the change in functional discomfort following intralesional bevacizumab injection and pterygium recurrence. Recurrence was defined as fibrovascular tissue growth invading the cornea. Therapeutic success was defined as the absence of pterygium recurrence in M6. Results: The mean age of the 60 patients was 54.17 ± 10.53. After bevacizumab injection, the preoperative functional discomfort score decreased significantly (P = 0.048). There was a significant improvement in grade and color intensity (P = 0.001). We noted no local nor systemic complications after intralesional injection of bevacizumab. After pterygium excision, the success rate was statistically higher in Group A (P = 0.047). There was no significant difference in either final best-corrected spectral visual acuity or astigmatism between the two groups. We noted a statistically significant association between recurrence and color intensity (P = 0.046), vascular density (P = 0.049), and the degree of elastic tissue degeneration (P = 0.040). Conclusion: A single preoperative subconjunctival injection of bevacizumab 1 month before surgery decreases the vascularity of newly formed blood vessels and hence may reduce the recurrence rate.

Cotton and Flax Textiles Leachables Impact Differently Cutaneous Staphylococcus aureus and Staphylococcus epidermidis Biofilm Formation and Cytotoxicity.

Bacteria can bind on clothes, but the impacts of textiles leachables on cutaneous bacteria remain unknown. Here, we studied for the first time the effects of cotton and flax obtained through classical and soft ecological agriculture on the representatives S. aureus and S. epidermidis bacteria of the cutaneous microbiota. Crude flax showed an inhibitory potential on S. epidermidis bacterial lawns whereas cotton had no effect. Textile fiber leachables were produced in bacterial culture media, and these extracts were tested on S. aureus and S. epidermidis. Bacterial growth was not impacted, but investigation by the crystal violet technique and confocal microscopy showed that all extracts affected biofilm formation by the two staphylococci species. An influence of cotton and flax culture conditions was clearly observed. Flax extracts had strong inhibitory impacts and induced the formation of mushroom-like defense structures by S. aureus. Conversely, production of biosurfactant by bacteria and their surface properties were not modified. Resistance to antibiotics also remained unchanged. All textile extracts, and particularly soft organic flax, showed strong inhibitory effects on S. aureus and S. epidermidis cytotoxicity on HaCaT keratinocytes. Analysis of flax leachables showed the presence of benzyl alcohol that could partly explain the effects of flax extracts.

Ascitic fluid cytology in malignant Brenner tumor: a case report.

BACKGROUND: Peritoneal effiusion is rare in malignant Brenner tumors and has been found in only 10% of patients. CASE: A 77-year-old woman presented with malignant Brenner tumor and ascites. The cytology of the ascitic fluid revealed many activated mesothelial cells intermingled with squamous tumoral cells. These cells were either isolated or arranged in small clusters. They were often round or oval with irregular and moderately hyperchromatic nuclei. CONCLUSION: Presence of squamous cells in ascitic fluid associated with an ovarian tumor should raise the possible diagnosis of malignant Brenner tumor in addition to malignant transformed teratoma and secondary squamous carcinoma of the ovary.

[Endometrial atypical complex hyperplasia with extensive squamous metaplasia: two cases]. / L'hyperplasie complexe atypique (HCA) de l'endomètre avec métaplasie malpighienne (MM) extensive. A propos de deux observations.

We report two cases of endometrial atypical complex hyperplasia with an extensive squamous hyperplasia occurring in two women aged 48 and 31 years old. The histological study showed an increase in the gland to stroma ratio with a false crowding aspect due to an extensive area of squamous metaplasia; some metaplastic areas were centered by necrosis. There was glandular cytologic atypia. Histologic examination is necessary to confirm the diagnosis and to definitively rule out adenocarcinoma.

[Clear-cell sarcoma of the kidney. Two pediatric cases]. / Sarcome à cellules claires du rein. A propos de deux cas pédiatriques.

Clear-cell sarcoma of the kidney is a rare pediatric renal sarcoma with poor prognosis and propensity to metastasize to bone. It is a distinctive renal malignancy regarded as a morphologic feature of Wilms' tumor. We report two cases occurring in four-year and 12-month-old boys, explored for abdominal masses. They were treated by surgery and chemotherapy. The histological diagnosis was clear cell sarcoma. Patients were doing well at 10 and seven months respectively.

[Chronic granulomatous disease in childhood]. / La maladie granulomateuse chronique de l'enfant.

Chronic granulomatous disease (GCD) of childhood is a rare inherited immunodeficiency. It is characterized clinically by the occurrence of severe and recurrent uncontrollable infections, which often lead to death in early childhood. The underlying biologic anomaly is a defective microbicidal capacity of phagocytosis with abnormal oxidative response during phagocytosis. Histologically, the GCD is characterized by a spectrum of histopathological features in a wide range of tissue specimens, often demonstrating features of active chronic inflammation, with or without non-caseating granuloma formation. The presence of numerous pigmented macrophages in association with such an inflammation should raise suspicion of the diagnosis. We report a case of a GCD in an 11-year-old boy and study the anatomoclinic features of this rare entity.

[Cholestasis caused by a choledochal botryoid rhabdomyosarcoma in a 22-month-old boy]. / Une choléstase causée par un rhabdomyosarcome botryoïde du cholédoque chez un nourrisson de 22 mois.

Botrioid rhabdomyosarcoma of the extrahepatic bile ducts is a rare cause of jaundice in children. It has a very poor prognosis and is rarely diagnosed preoperatively. We report a choledochal botrioid rhabdomyosarcoma in a 22-month-old boy who developed an obstructive jaundice. Radiographic explorations suggested cystic lymphangioma. The gallbladder, the cystic duct, the common bile duct and the pancreatic head were resected. The diagnosis was made on pathological examination; adjuvant chemotherapy followed. The patient was disease free 20 months following treatment.

[Malignant proliferating trichilemmal tumor]. / La tumeur trichilemmale proliférante maligne.

Proliferating trichilemmal tumor (PTT) is a rare distinctive lesion that usually occurs in the scalp of elderly women. About 40 cases of malignant PTTs have been reported. Alternatively, some authors have proposed that all PTT are squamous cell carcinomas. We report a case of a malignant PTT on the scalp in 44-year-old man. Clinical features and histological criteria for diagnosis of malignant versus benign PTT are discussed.

[Retroperitoneal well-differentiated inflammatory liposarcoma]. / Liposarcome bien différencié inflammatoire rétropéritonéal.

Inflammatory liposarcoma represents a rare variant of well-differentiated liposarcoma in which a chronic inflammatory infiltrate predominates simulating the appearance of malignant lymphoma and other nonneoplastic lesions. A case of this lesion occurring in the retroperitoneum was described in 43-year-old man. The differential diagnosis, especially from lymphoma and non neoplastic lesions such as inflammatory myofibroblastic tumor and Castelman disease are discussed.

[Inflammatory pseudotumor of the spleen: two case reports]. / Pseudotumeur inflammatoire de la rate: à propos de deux observations.

Inflammatory pseudotumor (IPT) of the spleen is an uncommon entity with debated etiology, characterized by a mixture of inflammatory cells and a component of myofibroblastic spindle cells. This lesion needs to be distinguished from the follicular dendritic cell tumor and the inflammatory myofibroblastic tumor. We report two cases of splenic PTI in a 69-year old and a 62-year old women. The tumors measured respectively 80 and 30 mn in greatest dimension. An inflammatory pseudotumor was histopathologically diagnosed following a splenectomy.