Platelet‐rich plasma counteracts detrimental effect of high‐glucose concentrations on mesenchymal stem cells from Bichat fat pad

Diabetic patients display increased risk of periodontitis and failure in bone augmentation procedures. Mesenchymal stem cells (MSCs) and platelet‐rich plasma (PRP) represent a relevant advantage in tissue repair process and regenerative medicine. We isolated MSCs from Bichat's buccal fat pad (BFP) and measured the effects of glucose and PRP on cell number and osteogenic differentiation potential. Cells were cultured in the presence of 5.5‐mM glucose (low glucose [LG]) or 25‐mM glucose (high glucose [HG]). BFP–MSC number was significantly lower when cells were cultured in HG compared with those in LG. Following osteogenic differentiation procedures, calcium accumulation, alkaline phosphatase activity, and expression of osteogenic markers were significantly lower in HG compared with LG. Exposure of BFP–MSC to PRP significantly increased cell number and osteogenic differentiation potential, reaching comparable levels in LG and in HG. Thus, high‐glucose concentrations impair BFP–MSC growth and osteogenic differentiation. However, these detrimental effects are largely counteracted by PRP.     

Human erythrocyte protein 4.2 deficiency associated with hemolytic anemia and a homozygous 40glutamic acid-->lysine substitution in the cytoplasmic domain of band 3 (band 3Montefiore)

Red blood cell (RBC) protein 4.2 deficiency is often associated with a moderate nonimmune hemolytic anemia, splenomegaly, and osmotically fragile RBCs resembling, but not identical to, hereditary spherocytosis (HS). In the Japanese type of protein 4.2 deficiency (protein 4.2Nippon), the anemia is associated with a point mutation in the protein 4.2 cDNA. In this report, we describe a patient with moderate and apparently episodic nonimmune hemolytic anemia with splenomegaly, spherocytosis, osmotically fragile RBCs, reduced whole cell deformability, and abnormally dense cells. Sodium dodecyl sulfate- polyacrylamide gel electrophoresis analysis of the proposita's RBC membrane proteins showed an 88% deficiency of protein 4.2 and a 30% deficiency of glyceraldehyde-3-phosphate dehydrogenase (band 6). Structural and molecular analyses of the proposita's protein 4.2 were normal. In contrast, limited tryptic digestion of the proposita's band 3 showed a homozygous abnormality in the cytoplasmic domain. Analysis of the pedigree disclosed six members who were heterozygotes for the band 3 structural abnormality and one member who was a normal homozygote. Direct sequence analysis of the abnormal band 3 tryptic peptide suggested that the structural abnormality resided at or near residue 40. Sequence analysis of the proposita's band 3 cDNA showed a 232G-->A mutation resulting in a 40glutamic acid-->lysine substitution (band 3Montefiore). Allele-specific oligonucleotide hybridization was used to probe for the mutation in the pedigree, showing that the proposita was homozygous, and the pedigree members who were heterozygous for the band 3 structural abnormality were also heterozygous for the band 3Montefiore mutation. The band 3Montefiore mutation was absent in 26 chromosomes from race-matched controls and in one pedigree member who did not express the band 3 structural abnormality. In coincidence with splenectomy, the proposita's anemia was largely corrected along with the disappearance of most spherocytes and considerable improvements of RBC osmotic fragility, whole cell deformability, and cell density. We conclude that this hereditary hemolytic anemia is associated with the homozygous state for band 3Montefiore (40glutamic acid-->lysine) and a decreased RBC membrane content of protein 4.2. We speculate that band 3 structural abnormalities can result in defective interactions with protein 4.2 and band 6, and in particular, that the region of band 3 containing 40glutamic acid is involved directly or indirectly in interactions with these proteins.     

Oral pilocarpine HCl stimulates labial (minor) salivary gland flow in patients with Sjögren's syndrome

Pilocarpine HCl has been shown to stimulate parotid and submandibular gland salivary flow. The purpose of this study was to determine whether this cholinergic-muscarinic drug also stimulates labial (minor) salivary gland (LSG) flow and to relate that with whole unstimulated salivary (WUS) flow rateS. Subjects diagnosed with primary Sjögren's syndrome (SS-1; n = 9) or secondary Sjögren's syndrome (SS-2; n = 9) were enrolled in this study after meeting stringent enrollment criteria. An age-gender matched control group was also enrolled. The labial saliva was collected in a standardized manner on Per-iopaper® for 5 min and the volume was analysed by the Periotron®.Whole unstimulated salivary samples were collected for 5 min by the method of Mandel and Wot-man (1976).Each subject was dosed with pilocarpine HCl (5 mg; tablets; p.o.).After 60 min the LSG flow as well as the WUS flow was determined again as previously. The results indicated a significant (>180%) increase in both labial salivary gland flow as well as whole salivary flow in the SS-1 and SS-2 subjects (mean ± S. e.m.): [SS-1: WUS = 0.1080 ± 0.03 vs 0.2242 ± 0.03 ml per 5 min; LSG = 93.1 ± 22.2 vs 167.8 ± 15.9 μl/5 min; P < 0.001; SS-2: WUS = 0.1384 ± 0.02 vs 0.2775 ± 0.09 ml per 5 min; LSG = 97.7 ± 20.2 vs 182.8 ± 17.9 μl per 5 min; P < 0.001]. These results indicate a significant increase in labial salivary gland flow as well as whole salivary flow as stimulated by pilocarpine HCI in Sjögren's syndrome patients.     

Detection of meticillin‐resistant staphylococcus aureus (MRSA) colonization in newborn infants using real‐time polymerase chain reaction (PCR)

Objective: Meticillin‐resistant staphylococcus aureus (MRSA) colonization on neonatal units is a common and important clinical problem. Effectiveness of polymerase chain reaction (PCR) for detecting MRSA nasal colonization of infants was evaluated and compared to culture‐based methods. The effect of skin decolonization in affected infants was studied. Methods: Paired nasal swabs were collected from infants in our neonatal unit over a 12‐month period (September 2007–2008). Colonization with MRSA was determined with a commercially available PCR method and compared to culture. Results: A total of 696 paired nasal swabs were taken. Three infants were colonized at the beginning and were included. There were positive PCRs in 12 infants. Five infants cultured MRSA from a nasal swab at the same time. No infants were culture‐positive when PCR was negative (sensitivity 100%, specificity 99% compared to culture). PCR results were available within 24 h. Five infants were PCR+ and isolated meticillin‐sensitive Staphylococcus aureus. This organism gave a false‐positive PCR result. Two infants transferred in on broad‐spectrum antibiotics were PCR+ and negative by culture. Decolonization led to negative nasal PCR and culture in 4/5 infants to discharge. Conclusions: PCR methods are sensitive and specific for detection of MRSA colonization in newborn infants of all gestations with results 1–2 days before culture.     

Fibrosing alveolitis: CT-pathologic correlation

Computed tomography (CT) was performed within 10 days of open lung biopsy in nine patients with fibrosing alveolitis. One-centimeter collimation contiguous scans through the chest were obtained in all patients. Additional 1.5-mm collimation scans were obtained in the area in which lung biopsy was later performed in six patients. In seven patients, CT demonstrated patchy involvement of the lung parenchyma, areas with a reticular pattern being intermingled with areas of normal lung. The reticular pattern was associated with cystic spaces 2-4 mm in diameter and was more severe in the lung periphery. Histologically, the reticular pattern corresponded to areas of irregular fibrosis. One patient had diffuse honeycombing (2-20-mm cysts), and one had honeycombing only in the lung periphery. In all patients, CT clearly defined the architectural changes seen on open lung biopsy. These changes were much better seen on the 1.5-mm than on the 10-mm collimation scans. CT may be helpful in determining the pattern and distribution of lung involvement in patients with fibrosing alveolitis and in guiding the surgeon to the most appropriate area(s) for biopsy.     

Pulmonary lymphangiomyomatosis: correlation of CT with radiographic and functional findings

In 14 patients with biopsy-proved lymphangiomyomatosis, disease extent at computed tomography (CT) was correlated with findings at chest radiography and pulmonary-function testing. The CT scans and chest radiographs were read independently by two chest radiologists. Disease extent was assessed on CT scans by using a visual score (0%-100% involvement of the lung parenchyma) and on radiographs by using an adaptation of the International Labour Office classification of the pneumoconioses. There was good concordance between the two observers for CT and radiographic scores (Kendall tau greater than or equal to .86, P less than .01). A significant but relatively low correlation was present between CT findings and radiographic severity of disease (r = .59, P less than .05). Impairment in gas exchange as assessed with the diffusing capacity correlated better with disease extent seen on CT scans (r = .69) than with chest radiographic findings (r = .59). Three patients had evidence of parenchymal disease on the CT scans but not on the radiographs. In one patient CT findings were negative despite a positive finding on chest radiographs. The authors conclude that CT is superior to chest radiography in the assessment of patients with lymphangiomyomatosis.