Heparanase regulates retention and proliferation of primitive Sca-1+/c-Kit+/Lin- cells via modulation of the bone marrow microenvironment

Heparanase is involved in tumor growth and metastasis. Because of its unique cleavage of heparan sulfate, which binds cytokines, chemokines and proteases, we hypothesized that heparanase is also involved in regulation of early stages of hematopoiesis. We report reduced numbers of maturing leukocytes but elevated levels of undifferentiated Sca-1⁺/c-Kit⁺/Lin^– cells in the bone marrow (BM) of mice overexpressing heparanase (hpa-Tg). This resulted from increased proliferation and retention of the primitive cells in the BM microenvironment, manifested in increased SDF-1 turnover. Furthermore, heparanase overexpression in mice was accompanied by reduced protease activity of MMP-9, elastase, and cathepsin K, which regulate stem and progenitor cell mobilization. Moreover, increased retention of the progenitor cells also resulted from up-regulated levels of stem cell factor (SCF) in the BM, in particular in the stem cell–rich endosteum and endothelial regions. Increased SCF-induced adhesion of primitive Sca-1⁺/c-Kit⁺/Lin^– cells to osteoblasts was also the result of elevation of the receptor c-Kit. Regulation of these phenomena is mediated by hyperphosphorylation of c-Myc in hematopoietic progenitors of hpa-Tg mice or after exogenous heparanase addition to wildtype BM cells in vitro. Altogether, our data suggest that heparanase modification of the BM microenvironment regulates the retention and proliferation of hematopoietic progenitor cells.      

Desorption electrospray ionization mass spectrometry: Imaging drugs and metabolites in tissues

Ambient ionization methods for MS enable direct, high-throughput measurements of samples in the open air. Here, we report on one such method, desorption electrospray ionization (DESI), which is coupled to a linear ion trap mass spectrometer and used to record the spatial intensity distribution of a drug directly from histological sections of brain, lung, kidney, and testis without prior chemical treatment. DESI imaging provided identification and distribution of clozapine after an oral dose of 50 mg/kg by: i) measuring the abundance of the intact ion at m/z 327.1, and ii) monitoring the dissociation of the protonated drug compound at m/z 327.1 to its dominant product ion at m/z 270.1. In lung tissues, DESI imaging was performed in the full-scan mode over an m/z range of 200-1100, providing an opportunity for relative quantitation by using an endogenous lipid to normalize the signal response of clozapine. The presence of clozapine was detected in all tissue types, whereas the presence of the N-desmethyl metabolite was detected only in the lung sections. Quantitation of clozapine from the brain, lung, kidney, and testis, by using LC-MS/MS, revealed concentrations ranging from 0.05 μg/g (brain) to a high of 10.6 μg/g (lung). Comparisons of the results recorded by DESI with those by LC-MS/MS show good agreement and are favorable for the use of DESI imaging in drug and metabolite detection directly from biological tissues.     

Thick Acellular Heart Extracellular Matrix with Inherent Vasculature: A Potential Platform for Myocardial Tissue Regeneration

The decellularization of porcine heart tissue offers many opportunities for the production of physiologically relevant myocardial mimetic scaffolds. Earlier, we reported the successful isolation of a thin porcine cardiac extracellular matrix (pcECM) exhibiting relevant bio-mechanical properties for myocardial tissue engineering. Nevertheless, since native cardiac tissue is much thicker, such thin scaffolds may offer limited regeneration capacity. However, generation of thicker myocardial mimetic tissue constructs is hindered by diffusion limitations (～100?μm), and the lack of a proper vascular-like network within these constructs. In our present work, we focused on optimizing the decellularization procedure for thicker tissue slabs (10-15?mm), while retaining their inherent vasculature, and on characterizing the resulting pcECM. The trypsin/Triton-based perfusion procedure that resulted in a nonimmunogenic and cell-supportive pcECM was found to be more effective in cell removal and in the preservation of fiber morphology and structural characteristics than stirring, sonication, or sodium dodecyl sulfate/Triton-based procedures. Mass spectroscopy revealed that the pcECM is mainly composed of ECM proteins with no apparent cellular protein remains. Mechanical testing indicated that the obtained pcECM is viscoelastic in nature and possesses the typical stress-strain profile of biological materials. It is stiffer than native tissue yet exhibits matched mechanical properties in terms of energy dissipation, toughness, and ultimate stress behavior. Vascular network functionality was maintained to the first three-four branches from the main coronary vessels. Taken together, these results reaffirm the efficiency of the decellularization procedure reported herein for yielding thick nonimmunogenic cell-supportive pcECM scaffolds, preserving both native tissue ultra-structural properties and an inherent vascular network. When reseeded with the appropriate progenitor cells, these scaffolds can potentially serve as ex vivo screening platforms for new therapeutics, as models for human cardiac ECM, or as biomedical constructs for patch or transmural transplantation strategies.     

Morphological and neuro-behavioral parallels in the rat model of stroke

Middle cerebral artery occlusion (MCAO) is widely used as a rat model of focal brain ischemia. Evaluation of brain damage often includes the morphological analysis of the injury area, MRI, and various scales which depend on functional tests, commonly known as neurological severity score (NSS). We determined the optimal number of NSS tests and assessed their capacity for non-invasive evaluation of brain ischemic injury in the rat MCAO model. 275 male Sprague-Dawley rats were randomly divided into five groups, given either permanent (p) MCAO or transient (t) MCAO using an uncoated 4-0 monofilament catheter or a silicone-coated monofilament. The rats’ neurological status was examined before and at 1 and 24 h following MCAO. The size of brain injury was then measured histologically and the extent of right cerebral hemisphere edema was calculated. We established a correlation between these tests and morphological data for brain injury. Adjusted R² of the prediction of total histology score was 0.7. The Hosmer-Lemeshow p-value of this model was 0.812 for total brain histology. For the brain edema the adjusted R² of the prediction model was 0.48. The Hosmer-Lemeshow p-value of this model was 0.558 for brain edema. Our methods of estimating infarct size produces reliable and well correlated results at 24 h and demonstrates to be an easy and quick way to assess infarct size soon after ischemic injury has occurred. The described method for neurological assessment could ultimately aid in assessing various treatment modalities in the early hours following stroke.     

Dumping syndrome following nissen fundoplication in an adult patient diagnosed by continuous online 13C/12C monitoring of 13C-Octanoic acid breath test "a case report"

Background

Gallbladder adenomyomatosis is a benign condition characterized by hyperplastic change in the gallbladder wall and overgrowth of the mucosa because of an unknown cause. Patients with gallbladder adenomyomatosis usually present with abdominal pain. However, we herein describe a case of a patient with gallbladder adenomyomatosis who did not present with abdominal pain, but with only fever.

Case presentation

A 34-year-old man presented to our hospital with a fever. No abdominal discomfort was declared. His physical examination showed no abnormalities. Ultrasound of the abdomen revealed thickness of the gallbladder. Acute cholecystitis was diagnosed. The fever persisted even after 1 week of antibiotic therapy. Magnetic resonance imaging of the abdomen showed gallbladder adenomyomatosis with intramural Rokitansky-Aschoff sinuses. Exploratory laparotomy with cholecystectomy was performed. The fever recovered and no residual symptoms were reported at the 3-year follow-up.

Conclusions

Gallbladder adenomyomatosis can present with fever as the only symptom. Although the association between gallbladder adenomyomatosis and malignancy has yet to be elucidated, previous reports have shown a strong association between gallbladder carcinoma and a subtype of gallbladder adenomyomatosis. Surgical intervention remains the first-choice treatment for patients with gallbladder adenomyomatosis.     

Athlete's hernia--a true, early direct inguinal hernia: diagnosis, pathophysiology, and surgical treatment

Athlete's hernia (AH) is an activity limiting condition that presents as chronic inguinal pain in elite athletes. The diagnosis involves a thorough history and physical examination and can be aided by ultrasound interrogation of the groin. Operative treatment with a direct tissue repair of the inguinal floor successfully alleviates symptoms and allows for full return to activity. A retrospective analysis of patients with the diagnosis of AH from January 1998 to May 2010 who underwent operative repair was reviewed. Patients were evaluated based on age, gender, sport, time to presentation, subjective and objective physical findings, imaging findings, operative findings, length of follow-up, and return to activity. Ninety-six patients (6 females) with a median age of 22.6 years were evaluated. In the majority of these patients, operative exploration revealed a wide external ring with separation of the fibers of the external oblique aponeurosis and an unprotected and bulging transverses abdominis aponeurosis, very akin to an early direct inguinal hernia. The mean initial follow-up time was 6 weeks at which point all but two of the patients were able to resume their full level of activity without restrictions. The diagnosis of AH, although somewhat elusive, can be easily established with a high degree of suspicion after doing a thorough history and physical exam augmented with ultrasonography. AH is equivalent to an early direct inguinal hernia found in young athletes and can be surgically corrected allowing return to full activity.     

Comparison of magnesium status using X-ray dispersion analysis following magnesium oxide and magnesium citrate treatment of healthy subjects

The magnesium content in food consumed in the Western world is steadily decreasing. Hypomagnesemia is associated with increased incidence of diabetes mellitus, metabolic syndrome, all-cause and coronary artery disease mortality. We investigated the impact of supplemental oral magnesium citrate versus magnesium oxide on intracellular magnesium levels ([Mg2+]i) and platelet function in healthy subjects with no apparent heart disease. In a randomized, prospective, double-blind, crossover study, 41 (20 women) healthy volunteers [mean age 53±8 (range 31-75) years] received either magnesium oxide monohydrate tablets (520 mg/day of elemental magnesium) or magnesium citrate tablets (295.8 mg/day of elemental magnesium) for one month (phase 1), followed by a four-week wash-out period, and then crossover treatment for one month (phase 2). [Mg2+]i was assessed from sublingual cells through x-ray dispersion (normal values 37.9±4.0 mEq/L), serum magnesium levels, platelet aggregation, and quality-of-life questionnaires were assessed before and after each phase. Oral magnesium oxide, rather than magnesium citrate, significantly increased [Mg2+]i (34.4±3 versus 36.3±2 mEq/L, p<0.001 and 34.7±2 versus 35.4±2 mEq/L, p=0.097; respectively), reduced total cholesterol (201±37 versus 186±27 mg/dL, p=0.016 and 187±28 versus 187±25 mg/dL, p=0.978; respectively) and low-density lipoprotein (LDL) cholesterol (128±22 versus 120±25 mg/dL, p=0.042 and 120±23 versus 121±22 mg/dL, p=0.622; respectively). Noteworthy is that both treatments significantly reduced epinephrine-induced platelet aggregation (78.9±16% versus 71.7±23%, p=0.013 and 81.3±15% versus 73.3±23%, p=0.036; respectively). Thus, oral magnesium oxide treatment significantly improved [Mg2+]i, total and LDL cholesterol compared with magnesium citrate, while both treatments similarly inhibited platelet aggregation in healthy subjects with no apparent heart disease.