Induction of neural-like differentiation in human mesenchymal stem cells derived from bone marrow, fat, spleen and thymus

Mesenchymal stem cells (MSCs) from bone marrow (BM) and sub-cutaneous fat are known to differentiate into neural cells under appropriate stimuli. We describe here the neural-like differentiation of human MSCs obtained from spleen and thymus, induced either with chemical factors or with co-culture with human Schwann cells (Sc). Under the effect of neural differentiation medium, most MSCs from BM, fat, spleen and thymus acquired morphological changes suggestive of cells of astrocytic/neuronal and oligodendroglial lineages with general up-regulation of neural molecules not correlated with morphological changes. The process was transient and reversible, as MSCs recovered basal morphology and phenotype, as well as their multilineage differentiation potential. Thus, we hypothesized that chemical factors may prime MSCs for neural differentiation, by inducing initial and poorly specific changes. By contrast, co-cultures of MSCs of different origin with Sc induced long-lasting and Sc differentiation, i.e., the expression of Sc myelin proteins for up to 12 days. Our results show that a MSC reservoir is present in tissues other than BM and fat, and that MSCs of different origin have similar neural differentiation potential. This evidence provides new insights into BM-like tissue plasticity and may have important implications for future therapeutic interventions in chronic neuropathies.     

Antimicrobial photodynamic therapy combined with conventional endodontic treatment to eliminate root canal biofilm infection

BACKGROUND AND OBJECTIVE: To compare the effectiveness of antimicrobial photodynamic therapy (PDT), standard endodontic treatment and the combined treatment to eliminate bacterial biofilms present in infected root canals. STUDY DESIGN/MATERIALS AND METHODS: Ten single-rooted freshly extracted human teeth were inoculated with stable bioluminescent Gram-negative bacteria, Proteus mirabilis and Pseudomonas aeruginosa to form 3-day biofilms in prepared root canals. Bioluminescence imaging was used to serially quantify bacterial burdens. PDT employed a conjugate between polyethylenimine and chlorin(e6) as the photosensitizer (PS) and 660-nm diode laser light delivered into the root canal via a 200-micro fiber, and this was compared and combined with standard endodontic treatment using mechanical debridement and antiseptic irrigation. RESULTS: Endodontic therapy alone reduced bacterial bioluminescence by 90% while PDT alone reduced bioluminescence by 95%. The combination reduced bioluminescence by >98%, and importantly the bacterial regrowth observed 24 hours after treatment was much less for the combination (P<0.0005) than for either single treatment. CONCLUSIONS: Bioluminescence imaging is an efficient way to monitor endodontic therapy. Antimicrobial PDT may have a role to play in optimized endodontic therapy.     

Fukutin gene mutations in steroid-responsive limb girdle muscular dystrophy

OBJECTIVE: Defects in glycosylation of alpha-dystroglycan are associated with several forms of muscular dystrophy, often characterized by congenital onset and severe structural brain involvement, collectively known as dystroglycanopathies. Six causative genes have been identified in these disorders including fukutin. Mutations in fukutin cause Fukuyama congenital muscular dystrophy. This is the second most common form of muscular dystrophy in Japan and is invariably associated with mental retardation and structural brain defects. The aim of this study was to determine the genetic defect in two white families with a dystroglycanopathy. METHODS: The six genes responsible for dystroglycanopathies were studied in three children with a severe reduction of alpha-dystroglycan in skeletal muscle. RESULTS: We identified pathogenic fukutin mutations in these two families. Affected children had normal intelligence and brain structure and shared a limb girdle muscular dystrophy (LGMD) phenotype, had marked elevation of serum creatine kinase, and were all ambulant with remarkable steroid responsiveness. INTERPRETATION: Our data suggest that fukutin mutations occur outside Japan and can be associated with much milder phenotypes than Fukuyama congenital muscular dystrophy. These findings significantly expand the spectrum of phenotypes associated with fukutin mutations to include this novel form of limb girdle muscular dystrophy that we propose to name LGMD2L.     

Pretherapeutic Extraperitoneal Laparoscopic Staging of Bulky or Locally Advanced Cervical Cancer

Background

To assess the safety, feasibility, and impact on survival of extraperitoneal para-aortic lymphadenectomy in the staging of patients with bulky or locally advanced cervical cancer.

Materials and Methods

Between August 2001 and October 2009, 87 consecutive patients (median age 51 years) with bulky or locally advanced cervical cancer underwent extraperitoneal laparoscopic infrarenal aortic and common iliac dissection as a pretherapeutic staging procedure. Data on pathologic findings, details of surgery, postoperative complications, and disease status at follow-up were collected.

Results

The median operating time was 150 min (range 60–255 min). The mean (± standard deviation) para-aortic nodal yield was 15.5 ± 8.1 (range 4–62). In none of the patients, conversion to the transperitoneal approach or laparotomy was necessary. Histological examination revealed metastasis in 13 patients (macroscopic disease 10, microscopic disease 3). After a median follow-up of 33.4 months (range 13.3–65.9 months), 73.6% of patients were free of disease and 1.1% were alive with disease, 19.5% died from cervical cancer, and 3.3% died from other causes. After a follow-up of 3 years, no deaths or recurrences were documented, with an overall survival rate of 74.8% (95% CI 62.8%–83.4%) and disease-free survival of 86% (95% CI 74.7%–92.5%). There were no significant differences in overall survival and disease-free survival between patients with positive and negative para-aortic lymph nodes.

Conclusion

The extraperitoneal laparoscopic para-aortic lymphadenectomy for pretherapeutic surgical staging in cervical cancer is a safe and feasible procedure that should be considered as a tool to identify lymph node positive patients who require extended-field radiation and/or chemotherapy.     

Disruption of hepatocyte growth factor/c-Met signaling enhances pancreatic beta-cell death and accelerates the onset of diabetes

OBJECTIVE

To determine the role of hepatocyte growth factor (HGF)/c-Met on β-cell survival in diabetogenic conditions in vivo and in response to cytokines in vitro.

RESEARCH DESIGN AND METHODS

We generated pancreas-specific c-Met-null (PancMet KO) mice and characterized their response to diabetes induced by multiple low-dose streptozotocin (MLDS) administration. We also analyzed the effect of HGF/c-Met signaling in vitro on cytokine-induced β-cell death in mouse and human islets, specifically examining the role of nuclear factor (NF)-κB.

RESULTS

Islets exposed in vitro to cytokines or from MLDS-treated mice displayed significantly increased HGF and c-Met levels, suggesting a potential role for HGF/c-Met in β-cell survival against diabetogenic agents. Adult PancMet KO mice displayed normal glucose and β-cell homeostasis, indicating that pancreatic c-Met loss is not detrimental for β-cell growth and function under basal conditions. However, PancMet KO mice were more susceptible to MLDS-induced diabetes. They displayed higher blood glucose levels, marked hypoinsulinemia, and reduced β-cell mass compared with wild-type littermates. PancMet KO mice showed enhanced intraislet infiltration, islet nitric oxide (NO) and chemokine production, and β-cell apoptosis. c-Met-null β-cells were more sensitive to cytokine-induced cell death in vitro, an effect mediated by NF-κB activation and NO production. Conversely, HGF treatment decreased p65/NF-κB activation and fully protected mouse and, more important, human β-cells against cytokines.

CONCLUSIONS

These results show that HGF/c-Met is critical for β-cell survival by attenuating NF-κB signaling and suggest that activation of the HGF/c-Met signaling pathway represents a novel strategy for enhancing β-cell protection.Type I diabetes is an autoimmune disease that results from cellular cytotoxicity leading to selective and progressive destruction of insulin-secreting cells (1–3). Many growth factors known to control cell growth and survival in physiologic and pathologic conditions are expressed in the pancreas and could potentially participate in an autocrine/paracrine fashion in the final fate of β-cells in an autoimmune environment. Overexpression of IGF-1, transforming growth factor-β, or granulocyte macrophage-colony stimulating factor ameliorates islet infiltration and β-cell death in mouse models of increased islet inflammation and diabetes (4–6). However, the role of endogenous pancreatic growth factors in type I diabetes has not been examined. Because growth factors can locally affect β-cell survival, neogenesis, and regeneration, and modulate chemokine production and immune responses, alterations in the level/activation of growth factor signaling pathways might contribute to the delay/acceleration of the onset of diabetes.Hepatocyte growth factor (HGF)/c-Met signaling pathway participates in the control of multiple biological functions, including development, proliferation, survival, regeneration, and branching morphogenesis (7). HGF binds with high affinity to, and induces the dimerization of, c-Met, its transmembrane tyrosine kinase receptor (8). Deletion of exon 16 of the c-Met gene, which encodes Lys¹¹⁰⁸ (ATP binding site), essential for the kinase activity of this receptor, in knockout mice results in embryonic lethality (9). These mice display a phenotype identical to HGF knockout mice (10). Both HGF and c-Met are expressed in the pancreas; HGF localizes to endothelial, islet, and mesenchymal cells, and c-Met is expressed in islet, ductal, and pancreatic progenitor cells (11–14). Conditional ablation of the c-Met gene in mouse β-cells using RIP-Cre and lox-c-Met mice leads to deficient insulin secretion without alteration of β-cell mass (12,13). On the other hand, HGF overexpression in the β-cell of transgenic mice increases β-cell replication, mass, and function (15,16). Furthermore, HGF improves islet graft survival in animal models of diabetes (17–19). HGF positively influences autoimmune responses, reducing the severity of autoimmune myocarditis and arthritis (20,21). HGF also downregulates airway and kidney inflammation, and inflammatory bowel disease (22–24). Whether HGF plays a role in autoimmune diabetes is unknown.To address the function of c-Met in the development, growth, and maintenance of β-cells under physiologic conditions, as well as its role in β-cell survival and response to injury in vivo, we generated pancreas-specific c-Met-null (PancMet KO) mice. We report that although c-Met is dispensable for normal β-cell growth and function under basal conditions, it is critically important for β-cell survival in diabetogenic conditions. β-Cell survival is dramatically worsened in the absence of HGF/c-Met signaling, resulting in accelerated diabetes onset. These observations also apply to human β-cells, underscoring a therapeutic opportunity for the HGF/c-Met signaling pathway in human diabetes.     

Anatomical study of the pre-retinacular fat pad of the wrist: application to a new surgical approach to the carpal tunnel

INTRODUCTION: Decompression of the median nerve in the carpal tunnel by section of the flexor retinaculum is the generally accepted treatment for carpal tunnel syndrome and is usually effective in relieving the symptoms. Following postoperative observations we proposed the hypothesis that incisional pain following open carpal tunnel release could be partly explained by injury to the fat pad situated between the palmar carpal ligament and the flexor retinaculum. METHOD: We performed an anatomical study on 20 fresh adult latex injected upper limbs. RESULTS: The sus-retinacularis fat pad is a real anatomical structure, clearly delineated and located inside a defined fibrous space with its own innervation from the ulnar nerve. It lies in the path of the normal carpal tunnel approach. DISCUSSION: Although most postoperative scar tenderness is attributed to neuroma formation because of injury to transverse branches of the palmar cutaneous nerves, we nevertheless consider that injury to the preretinacular fat pad also plays a part. We propose a modified approach to the carpal tunnel. This is a safe and simple method which respects the integrity of the sus-retinacularis fat pad so as to minimise the extent of scar tenderness.     

Mycophenolate mofetil vs. sirolimus in kidney transplant recipients receiving tacrolimus-based immunosuppressive regimen

Abstract:  Mycophenolate mofetil (MMF) and sirolimus (SRL) are effective immunosuppressive drugs with distinct safety profile.
Methods:  Kidney transplant recipients receiving tacrolimus (TAC)-based immunosuppressive regimen were randomized to receive fixed daily doses of MMF (2 g/d, n = 50) or SRL (one loading dose of 15 mg, 5 mg/d till day 7 and 2 mg/d thereafter, n = 50) without induction therapy.
Results:  No differences were observed in the incidence of the composite (biopsy-confirmed acute rejection, graft loss or death) end-point (18% vs. 16%, p = 1.000), biopsy confirmed acute rejection (12% vs. 14%, p = 1.000), one-yr patient (94% vs. 98%, p = 0.308), graft (92% vs. 98%, p = 0.168), and death-censored graft survival (98% vs. 100%, p = 0.317) comparing patients receiving MMF or SRL respectively. Patients receiving SRL showed worse safety outcomes, higher mean creatinine (1.6 ± 0.5 mg/dL vs. 1.4 ± 0.3 mg/dL, p = 0.007), higher proportion of patients with proteinuria (52.0% vs. 10.7%, p = 0.041), higher mean urinary protein concentrations (0.3 ± 0.5 g/L vs. 0.1 ± 0.2 g/L, p = 0.012), higher mean cholesterol concentration (217 mg/dL vs. 190 mg/dL, p = 0.030), and higher proportion of patients prematurely discontinued from randomized therapy (26% vs. 8%, p = 0.031).
Conclusion:  In patients receiving TAC, MMF produced similar efficacy but superior safety profile compared with SRL.     

Arteriovenous fistula for long-term venous access for boys with hemophilia

OBJECTIVES: Hemophilia is a sex-linked condition affecting about 1 of every 5000 males in the United States. The management of children with hemophilia can be improved with regular intravenous infusion of factor VIII or IX, thus preventing crippling and sometimes fatal hemorrhage. Maintaining this vital intravenous access is often hampered by gradual loss of superficial veins or repeated central catheter sepsis and thrombosis. This study reviewed an experience with arteriovenous fistula in selected hemophilia patients with limited venous access. METHODS: Consecutive patients operated on between October 2000 and July 2006 for venous access with the creation of an arteriovenous fistula were reviewed. They were selected because of repeated problems with other venous access. Patency, ease of use, duplex scan derived brachial artery diameter, and arm length were assessed. RESULTS: During a 69-month period, 10 arteriovenous fistulas (five brachial artery-basilic vein fistulas, 5 brachial artery-cephalic vein fistulas) were created for nine patients. The patients were a median age of 5.5 years (range, 1 to 27 years), and all were <13 except the 27-year-old patient. There were no postoperative hematomas requiring evacuation. One arteriovenous fistula failed to mature and was redone in the opposite arm, which subsequently occluded after 13 months. Of the mature fistulas, patency was 100% at 1 year, 80% (4/5) at 3 years, and 75% (3/4) at 4 years, with mean follow-up of 22 months. Brachial artery diameter increased in the involved arm by a ratio of 1.95 (range, 1.51 to 2.5) compared with the opposite arm. Arm length disparity was increased by 0.5 cm (range, 0.8 to 1.5 cm) in the involved arm. All fistulas allowed good access at home by a care provider. CONCLUSIONS: For hemophilia patients with compromised venous access, arteriovenous fistulas provide good early patency. Brachial artery diameter and arm length require continued follow-up.     

Prolonged duration of surgery is not a risk factor for postoperative complications in patients undergoing total thyroidectomy: a single center experience in 305 patients

Background

Hypocalcemia and nerve injury are the most severe complications after thyroid surgery. The duration of surgery has not been previously considered as a risk factor for postoperative complications in patients undergoing total thyroidectomy. We sort to investigate the influence of prolonged surgery on postoperative complications in patients undergoing total thyroidectomy.

Methods

We hypothesized that a threshold of?>?120 minutes of surgical time could represent a surrogate marker for postoperative complications in patients undergoing total thyroidectomy for benign thyroid disorders. The study population was divided into two groups based on the median duration of surgery (120 min): group I?≤?120 minutes (control group), group II?>?120 minutes (study group). The charts of eligible patients undergoing total thyroidectomy within a six-year period from January 1^st 2006 to December 31^st 2012 were reviewed. The primary outcomes included the rates postoperative hypocalcemia and recurrent laryngeal nerve palsy. The secondary outcomes included the rates of postoperative hemorrhage, wound dehiscence and length of hospital stay.

Results

305 cases of thyroidectomy were included for analysis; 130 (42.6%) control group and 175 (57.4%) study group. Transient (15.4% vs 19.4%) and permanent (3.8% vs. 2.9%) hypocalcemia were recorded in control and study group respectively. The incidence of nerve palsy was 1.5% in the control group and 1.4% in the study group. The mean length of postoperative hospital stay was 3d in both groups. There was no significant difference amongst both groups with regard to postoperative bleeding (p?=?0.57) and wound dehiscence (p?=?0.31). Prolonged surgery (> 120 min) was not identified as a risk factor for increased postoperative complication.

Conclusion

Prolonged duration of surgery?>?120 minutes is not a surrogate marker for postoperative complications in patients undergoing total thyroidectomy.

     

A multidisciplinary rehabilitation programme improves disability,kinesiophobia and walking ability in subjects with chronic low back pain: results of a randomised controlled pilot study

Purpose

To evaluate the effect of a multidisciplinary rehabilitation programme on disability, kinesiophobia, catastrophizing, pain, quality of life and gait disturbances in patients with chronic low back pain (CLBP).

Methods

This was a parallel-group, randomised, superiority-controlled pilot study in which 20 patients were randomly assigned to a programme consisting of motor training (spinal stabilising exercises plus usual-care) and cognitive–behavioural therapy (experimental group, 10 subjects) or usual-care alone (control group, 10 subjects). Before treatment, 8 weeks later (post-treatment), and 3 months after the end of treatment, the Oswestry Disability Index, the Tampa Scale for Kinesiophobia, the Pain Catastrophizing Scale, a pain numerical rating scale, and the Short-Form Health Survey were assessed. Spatio-temporal gait parameters were also measured by means of an electronic walking mat. A linear mixed model for repeated measures was used for each outcome measure.

Results

The programme had significant group (p = 0.027), time (p < 0.001), and time-by-group interaction (p < 0.001) effects on disability, with the experimental group showing an improvement after training of about 61 % (25 % in the control group). The analyses of kinesiophobia, catastrophizing, and the quality of life also revealed significant time, group, and time-by-group interaction effects in favour of the experimental group, and there was a significant effect of time on pain. Both groups showed a general improvement in gait parameters, with the experimental group increasing cadence significantly more.

Conclusion

The multidisciplinary rehabilitation programme including cognitive–behavioural therapy was superior to the exercise programme in reducing disability, kinesiophobia, catastrophizing, and enhancing the quality of life and gait cadence of patients with CLBP.