Mesenchymal stem cell exosomes in bone regenerative strategies-a systematic review of preclinical studies.

The ability of bone for regeneration has long been recognized. However, once beyond a critical size, spontaneous regeneration of bone is limited. Several studies have focused on enhancing bone regeneration by applying mesenchymal stromal/stem cells (MSCs) in the treatment strategies. Despite the therapeutic efficacy of MSCs in bone regeneration, cell-based therapies are impeded by several challenges in maintaining the optimal cell potency and viability during expansion, storage, and final delivery to patients. Recently, there has been a paradigm shift in therapeutic mechanism of MSCs in tissue repair from one based on cellular differentiation and replacement to one based on secretion and paracrine signaling. Among the broad spectrum of trophic factors, extracellular vesicles â€‹particularly the exosomes have been reported to be therapeutically efficacious in several injury/disease indications, including bone defects and diseases. The current systematic review aims to summarize the results of the existing animal studies which were conducted to evaluate the therapeutic efficacy of MSC exosomes for bone regeneration. Following the Preferred Reporting Items for Systematic Reviews and Meta-analysis â€‹guidelines, the PubMed and The Cochrane Library database were searched for relevant controlled preclinical animal studies. A total of 23 studies were identified, with the total sample size being 690 rats or mice and 38 rabbits. Generally, MSC exosomes were found to be efficacious for bone regeneration in animal models of bone defects and diseases such as osteonecrosis and osteoporosis. In these studies, MSC exosomes promoted new bone formation with supporting vasculature â€‹and displayed improved morphological, biomechanical, and histological outcomes, coupled with positive effects on cell survival, proliferation, and migration, osteogenesis, and angiogenesis. Unclear-to-low risk in bias and incomplete reporting in the primary studies highlighted the need for standardization in outcome measurements and reporting. Further studies in large animal models to establish the safety and efficacy would provide useful information on guiding the design of clinical trials.

Identification of small droplets of photosynthetic squalene in engineered Synechococcus elongatus PCC 7942 using TEM and selective fluorescent Nile red analysis.

To identify microbial squalene that has been widely used in various industrial applications, intracellular formation of photosynthetic squalene was investigated using the previously engineered Synechococcus elongatusPCC 7942 strain. Unlike the proposed localization of squalene in the membrane bilayer, small droplets were identified in the cytoplasm of S. elongatusPCC 7942 as squalene using transmission electron microscopy analysis. Determination of the diameters of the squalene droplets with manual examination of 1016 droplets in different squalene-producing strains indicated larger squalene droplets in larger cells. Based on the observation of a sole droplet of squalene in a cyanobacterium, fluorescent Nile red was used for the selective staining of squalene. The fluorescent intensities were correlated with squalene contents determined using gas chromatography-mass spectrometry. Photosynthetic squalene was identified as a small droplet in S. elongatusPCC 7942, and this noninvasive quantitative method could be useful to promote high-throughput strain development for squalene production. SIGNIFICANCE AND IMPACT OF THE STUDY: Engineering of Cyanobacteria has focused on sustainable production of squalene by converting CO2 . Before improving the photosynthetic squalene production, we characterized formation of squalene, showing small droplets in the cytoplasm instead of single granule. Based on the finding and the analysis, this study has provided valuable evidences how further metabolic engineering strategies should apply to enhance the production yield.

Performance of point-of-care diagnosis of AIDS: label-free one-step-immunoassay vs. lateral flow assay.

The objective of this study is to develop an accurate, rapid, simple, and label-free assay technology that enables point-of-care diagnosis of AIDS. For this, 3-dimensional (3D) probes to sensitively detect anti-HIV antibodies were designed and synthesized by genetically presenting a HIV antigen (gp41) on the surface of engineered human ferritin nanoparticles. The 3D probes also present multi-copies of the hexa-histidine peptide (H6) on their surface to chemisorb gold ions (Au3+), which is essential for the generation and self-enhancement of assay signals. The developed new assay technology (named "one-step-immunoassay") quickly produced clear optical signals through a simple and convenient one-step procedure. The diagnostic performance of the one-step-immunoassay was compared with that of the conventional lateral flow assay (LFA) using 30 AIDS patient and 20 healthy sera. The sensitivity of LFA was only 63% when a single antigen (gp41) was used but enhanced to 90% when three different antigens (gp41, p24, and gp120) were used together as the assay probes. In contrast, the one-step-immunoassay using only gp41 produced strong optical signals within 15 min without causing any false negative/positive signals, showing 100% sensitivity and 100% specificity and holding promising potential for clinical point-of-care diagnosis of AIDS.

Association between childhood socioeconomic position and periodontitis in Korean adults.

OBJECTIVE: To examine the relationship of early life socioeconomic position (SEP) and adulthood periodontitis in the middle aged Korean representative sample. METHODS: The 4th Korea National Health and Nutrition Examination Survey data were used. Multivariate logistic regression analyses were conducted on adults aged 30-59 years to estimate the association between parental SEP (education, occupation) and periodontitis and assess the relative impacts of own SEP (education, income and occupation) on periodontitis. Periodontitis (Community Periodontal Index) was dependent variable and parental SEPs were independent variables. RESULTS: Own SEP was associated with periodontitis (OR of own education=1.94, OR of own occupation=1.67; OR of the lowest income=1.52). Income was associated with periodontitis after adjustment for own SEPs and parental SEPs simultaneously (adjusted OR of the lowest income=1.68). Parental SEP was associated with periodontitis (OR of father's education=1.66, OR of mother's education=l.64; OR of father's occupation=1.38, OR of mother's occupation=1.44). CONCLUSIONS: Early-life socioeconomic disadvantages were significantly associated with adulthood periodontitis in the representative Korean sample (p<0.05). The results also indicated that systematic oral health program and oral education would be needed from early childhood throughout the whole life time to improve periodontal health in adulthood.

Complementary limiting factors of astaxanthin synthesis during photoautotrophic induction of Haematococcus pluvialis: C/N ratio and light intensity.

We investigated the effect of carbon/nitrogen (C/N) ratio on astaxanthin synthesis in Haematococcus pluvialis during photoautotrophic induction by continuous input of both CO(2)-air mixture and intense light. When H. pluvialis was induced by constant irradiance induction at 200 micromol photon m(-2) s(-1), there was a positive correlation with astaxanthin content and C/N ratio, which was similar to the case for heterotrophic induction. Lower C/N ratios did not retard Haematococcus encystment, but did increase culture biomass, resulting in a decrease in astaxanthin production because of light limitation. However, induction using variable irradiance showed that reduction of astaxanthin production at low C/N ratios was successfully overcome by simply increasing the light intensity from 200 to 300 micromol photon m(-2) s(-1) to overcome the light limitation. This resulted in a greatly enhanced astaxanthin synthesis in proportion to cell density in cultures with low C/N ratios. Our results indicate that light intensity is more critical than C/N ratio in astaxanthin production by H. pluvialis during photoautotrophic induction.

Comparison of heterotrophic and photoautotrophic induction on astaxanthin production by Haematococcus pluvialis.

During light induction for astaxanthin formation in Haematococcus pluvialis, we substituted photoautotrophic induction for heterotrophic induction using acetate, both to prevent contamination by heterotrophs due to addition of organic carbon and to enhance carbon assimilation in the induced cells. Strong photoautotrophic induction was performed by N-deprivation of photoautotrophically grown Haematococcus cells followed by supplementation with bicarbonate (HCO(3)(-)) or CO(2). Bicarbonate-induced cells contained more astaxanthin than acetate-induced cells, and even further enhancement of astaxanthin accumulation was achieved by continuous CO(2) supply. The maximum astaxanthin content (77.2 mg g(-1) biomass, 3.4-fold higher than with heterotrophic induction) was obtained under conditions of 5% CO(2), yielding astaxanthin concentration and productivity of 175.7 mg l(-1) and 6.25 mg l(-1) day(-1), respectively. The results indicate that photoautotrophic induction is more effective than heterotrophic induction for astaxanthin synthesis in H. pluvialis.

Treatment of highly polluted groundwater by novel iron removal process.

The removal of ferrous iron (Fe(II)) in groundwater has been generally achieved by simple aeration, or the addition of an oxidizing agent. Aeration has been shown to be very efficient in insolubilization ferrous iron at a pH level greater than 6.5. In this study, pH was maintained over 6.5 using limestone granules under constant aeration to oxidize ferrous iron in groundwater in a limestone packed column. A sedimentation unit coupled with a membrane filtration was also developed to precipitate and filtrate the oxidized ferric compound simultaneously. Several bench-scale studies, including the effects of the limestone granule sizes, amounts and hydraulic retention time on iron removal in the limestone packed column were investigated. It was found that 550 g/L of the 7-8 mesh size limestone granules, and 20 min of hydraulic retention time in the limestone packed column, were necessary for the sufficient oxidation of 40 mg/L of iron(II) in groundwater. Long-term operation was successfully achieved in contaminated waters by removing the iron deposits on the surface of the limestone granule by continuous aeration from the bottom of the column. Periodic reverse flow helped to remove caking and fouling of membrane surface caused by the continuous filtration. Recycling of the treated water from the membrane right after reverse flow operation made possible an admissible limit of iron concentration of the treated water for drinking. The pilot-scale process was constructed and has been tested in the rural area of Korea.

Metastatic renal cell carcinoma to the bladder: a clinicopathologic and immunohistochemical study.

Although rare, renal cell carcinoma (RCC) can metastasize to the bladder. When this occurs, it might complicate diagnosis. Morphologically, RCC can be confused with transitional cell carcinomas (TCCs), especially those exhibiting clear cell features, and also with other bladder tumors, such as paragangliomas and metastatic melanomas. We report seven cases of RCC metastatic to the bladder that occurred in 6 men and 1 woman who were 35 to 69 years old. The most common presenting symptom was the reappearance of hematuria, which developed from 2 to 131 months (mean, 41.3 mo) after the removal of the primary RCC. In all of the patients, the metastatic RCC involved multiple organs; no case had an isolated metastasis to the bladder. The prognosis was poor, and five patients died of disease between 4 and 24 months (mean, 12.8 mo) after diagnosis of the metastasis to the bladder. The remaining two patients were lost to follow-up. All of the tumors were conventional clear or "granular" cell RCCs, with nuclear grades of 2 or 3. In five patients, metastases were confined to the lamina propria, but in two patients, tumors involved the muscularis propria as well. A comparative immunohistochemical study showed that metastatic RCCs were positive for CAM5.2, vimentin, and Leu-M1, and negative for cytokeratin 20, cytokeratin 7, 34betaE12, carcinoembryonic antigen, S-100 protein, HMB45, and chromogranin. Classic and clear cell TCCs were positive for all of the cytokeratins and carcinoembryonic antigen and negative for vimentin. Paragangliomas were positive for chromogranin and showed scattered positivity for the S-100 protein in the sustentacular cells. Metastatic melanomas were positive for S-100 protein and HMB45. The histologic appearance of RCC, particularly the delicate fibrovascular stroma with abundant sinusoidal vessels, is a feature that can be used to recognize the tumor. When there is difficulty diagnosing metastatic RCC, TCC, or other tumors in the bladder, the immunohistochemical findings can assist in the differential diagnosis.

Sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid: report of two patients, one with distant metastasis, and review of the literature.

Sclerosing mucoepidermoid carcinoma with eosinophilia (SMECE) is a recently recognized malignant neoplasm of the thyroid gland. Two additional cases of this condition which occurred in a 70-year-old woman and a 69-year-old woman are presented. The case of the 70-year-old woman (patient 1) is the first report of distant metastasis, besides lymph node metastasis, for this type of tumor. The patient initially presented with a thyroid mass, and the thyroid gland with surrounding cervical lymph nodes was removed. Because of focal keratin "pearl" formation, the tumor was misinterpreted as a metastatic squamous cell carcinoma to the thyroid. Approximately 4 years later, the patient developed a left supraclavicular mass and lung densities. A pathological fracture of the right humeral head followed, and the left supraclavicular mass recurred along with newly developed subcutaneous nodules on the chest wall and arm. Open lung and bone biopsies revealed metastatic SMECE, which was morphologically identical to that of the thyroid mass. The 69-year-old woman (patient 2) had, in 1983, undergone thyroidectomy with left radical neck dissection; this had been diagnosed as follicular carcinoma of the thyroid with lymph node involvement. After multiple isolated lymph nodes metastases, the patient developed locally extensive, recurrent tumor that showed microscopic features of SMECE. Review of the previous thyroid tumor and lymph nodes revealed the same type of histology. To our knowledge, only a single report containing eight cases of this distinctive carcinoma of the thyroid has been published. Herein we describe characteristic morphological features of two additional cases of this rare malignancy, one with distant metastasis, and we review the related literature.

PHA synthase activity controls the molecular weight and polydispersity of polyhydroxybutyrate in vivo.

A synthetic operon for polyhydroxyalkanoate (PHA) biosynthesis designed to yield high levels of PHA synthase activity in vivo was constructed by positioning a genetic fragment encoding beta-ketothiolase and acetoacetyl-CoA reductase behind a modified synthase gene containing an Escherichia coli promoter and ribosome binding site. Plasmids containing the synthetic operon and the native Alcaligenes eutrophus PHA operon were transformed into E. coli DH5 alpha and analyzed for polyhydroxybutyrate production. The molecular weight of polymer isolated from recombinant E. coli containing the modified synthase construct, determined by multiangle light scattering, was lower than that of the polymer from E. coli containing the native A. eutrophus operon. A further decrease in polyester molecular weight was observed with increased induction of the PHA biosynthetic genes in the synthetic operon. Comparison of the enzyme activity levels of PHA biosynthetic enzymes in a strain encoding the native operon with a strain possessing the synthetic operon indicates that the amount of polyhydroxyalkanoate synthase in a host organism plays a key role in controlling the molecular weight and the polydispersity of polymer.

Serum calcitonin in small cell carcinoma of the prostate.

Small cell carcinoma (SCC) of the prostate is a rare and recently recognized subtype of prostate cancer. The neuroendocrine component of the prostate carcinoma is becoming more frequently detected in classic adenocarcinoma of the prostate. Clinically, these tumors represent a considerable portion of so called androgen independent prostatic carcinomas. It has been hypothesized that the neuroendocrine cells being admixed with adenocarcinoma is selected and emerges as a hormone refractory carcinoma after the androgen blockade. The SCC shows a spectrum from a mixed adenocarcinoma with SCC component to the extreme case of pure SCC. Characteristically, prostatic SCC shows low measurable serum level of traditional prostate tumor marker, prostatic specific antigen (PSA). Instead, SCC secretes several neural peptides and calcitonin (CT) is one of them. The usefulness of serum CT as a neuroendocrine marker was evaluated retrospectively in 16 patients with SCC of the prostate (5 pure SCCs and II combined adenocarcinoma and SCCs). The serum CT was measured by radioimmunoassay. In all the patients, serum CT level was measured after SCC was diagnosed histologically. All 16 patients presented with advanced tumor with extensive metastasis. Nine (56 percent) out of 16 cases showed elevated serum CT (range 42 approximately 2,654 pg/ml) and chemically supported the diagnosis of SCC. Owing to the retrospective nature of the study, the serum CT was measured only once in most of the cases, and the value of monitoring the disease progress or the responsiveness to the chemotherapy could not be evaluated. Survival analysis by logrank test did not show statistically significant prognostic value of serum CT in SCCs of the prostate. However, patients with extremely high serum CT level tend to have poor survival. Future studies are needed for further evaluation of serum CT as a disease monitor and prognostic marker in SCC of the prostate. Serum CT may have a role as a tumor marker in the early diagnosis of SCC of the prostate, which often is not diagnosed until the advanced stage.

Allergic fungal sinusitis: a clinicopathologic study of 16 cases.

Allergic fungal sinusitis (AFS) has been clinicopathologically defined as a noninvasive form of fungal infection. Etiologically, most reported cases have been attributed to pigmented dematiaceous fungi. The authors report 16 cases of AFS from our institution, along with a review of cases from the literature. The patients' age ranged from 8 to 71 years, with a mean age of 25 years. All patients were immunocompetent, although six had a strong history of atopy. Multiple sinuses were affected in all cases; nine patients had bilateral involvement, and seven patients manifested unilateral involvement. Histopathologically, all cases were characterized by the presence of "allergic mucin," with scattered fungal organisms without invasion of mucosa or bone. Fontana-Masson stain identified fungi in all but one case and assisted in distinguishing the pigmented dematiaceous organisms from other septated fungal forms. Accordingly, Fontana-Masson stain can be useful in confirming the diagnosis of AFS in the lack of tissue culture results. Fungal cultures performed on six cases grew Exserohilum (three cases), Bipolaris (one case), Drechslera (Bipolaris) (one case), and Curvularia (one case). All patients were treated with surgical debridement and sinus aeration. Follow-up of at least 6 months was obtained in six cases, of which four showed recurrent disease between 8 months and 4 years after the initial surgical procedure. A literature review showed that the most common etiologic agents were members of the dematiaceous family (81%), with the most common genus being Bipolaris (42%), followed by Curvularia (21.3%). It is believed that type I and III hypersensitivity reactions underlie the pathogenesis of this disease.

Shikonin production by extractive cultivation in transformed-suspension and hairy root cultures of Lithospermum erythrorhizon.

Effects of in situ extraction, fungal elicitation, a permeabilizing agent, and the oxygen transfer rate on shikonin production in transformed suspension and hairy root cultures of Lithospermum erythrorhizon were studied. Shikonin production with in situ extraction in transformed cell and hairy root cultures by n-hexadecane was 7.6 and 3 times higher than those of the control culture. Shikonin production of transformed L. erythrohizon increased with the enhanced gas exchange, and in situ extraction also increased sucrose consumption and shikonin production. The optimal volume of n-hexadecane in the hairy root culture was similar to that in the transformed cell cultures. In situ extraction at an earlier stage significantly enhanced shikonin production both in transformed cell and hairy root cultures. Dimethylsulfoxide used as a permeabilizing agent was harmful to cell growth and shikonin production, and permeabilizing was unnecessary when in situ extraction was applied. This occurred because with the solvent addition, most shikonin was spontaneously released from the cells and was dissolved in the solvent layer. The combined addition of n-hexadecane of the extract of the fungus Penicillium as an elicitor seemed to result in a higher production of shikonin both in cell suspensions and transformed root cultures. However, an increase of shikonin induction by fungal elicitation in a hairy root culture was not significant in comparison with that of normal cell cultures.

Immunohistochemical differentiation of atypical hyperplasia vs. carcinoma in situ of the breast.

The distinction between atypical hyperplasia and carcinoma in situ in breast lesions can be difficult. The identification of myoepithelial cell layers may be helpful in establishing a diagnosis of proliferative breast disease vs. intraepithelial neoplasia. We reviewed pathologic material on 20 cases of atypical hyperplasia and 29 cases of carcinoma in situ. Immunohistochemical stains were employed against muscle-specific actin, S-100 protein, and cytokeratin to identify myoepithelial cells and to recognize different staining patterns. In atypical hyperplasia, muscle-specific actin staining identified myoepithelial cells in fine branching fibrovascular layers or as scattered cells between other proliferating cells. This pattern was absent in carcinoma in situ. S-100 protein showed more positive staining in atypical hyperplasia than in carcinoma in situ with patterns distinct from muscle-specific actin. Immunostaining for cytokeratin demonstrated distinctly different patterns between the two lesions. This study suggests that muscle-specific actin, S-100 protein, and cytokeratin in combination may assist in distinguishing proliferative breast disease with atypia from carcinoma in situ.