Thirty-day outcomes for children and adolescents undergoing laparoscopic sleeve gastrectomy at a free-standing children's hospital.

The obesity epidemic continues to affect millions of children and adolescents. Non-surgical options do not result in significant or sustained weight loss; thus bariatric surgery has become increasingly utilized. Limited data exist regarding safety for paediatric bariatric surgery, especially outside of National Institutes of Health (NIH)-funded centres. We hypothesized that the perioperative outcomes of paediatric patients undergoing laparoscopic sleeve gastrectomy (LSG) at our free-standing children's hospital would provide adequate safety profiles. We retrospectively reviewed demographics, comorbidities and 30-d outcomes for all patients who underwent LSG from 2010 to 2015 at a free-standing children's hospital. A total of 105 patients underwent 107 LSG procedures (two revisions). Mean age was 17.2 ± 2.4 years. Male to female ratio was 1:4. The majority were Black (57.1%), followed by White (21.0%) and Hispanic (18.1%). The mean body mass index was 51.0 ± 9.8 kg/m2 . Comorbidities included obstructive sleep apnea (59.0%), hypertension (15.2%), polycystic ovarian disease (16.7% of females only), depression (12.4%) and diabetes (11.4%). Median length of stay was 2.0 d (1-7 d). There were no deaths. Major complications occurred in four patients (3.8%); three required reoperation. Four patients (3.8%) experienced minor complications. Laparoscopic sleeve gastrectomy can be safely performed for children and adolescents at a free-standing children's hospital without NIH-support.

Melanocortin-4 receptor signaling is not required for short-term weight loss after sleeve gastrectomy in pediatric patients.

Homozygous or compound heterozygous melanocortin-4 receptor (MC4R) mutations are rare with fewer than 10 patients described in current literature. Here we report the short- and long-term outcomes for four children ages 4.5-14 who are homozygous for loss-of-function mutations in the MC4R and underwent laparoscopic sleeve gastrectomy. All four patients experienced significant weight loss and improvement in, or resolution of, their comorbidities in the short term. One patient, however, has had significant weight regain in the long term. We conclude that MC4R signaling is not required for short-term weight loss after laparoscopic sleeve gastrectomy in children. Behavior modification may be more important for long-term weight maintenance, but patients with homozygous MC4R deficiency should not be excluded from consideration for sleeve gastrectomy. However, as at least one copy of functional MC4R is necessary and sufficient to induce long-term postoperative weight loss benefits, patients with complete loss of MC4R functionality might be less likely to exhibit the same benefits resulting from bariatric surgery.

Differentiation of human dental stem cells reveals a role for microRNA-218.

BACKGROUND: Regeneration of lost periodontium is the ultimate goal of periodontal therapy. Advances in tissue engineering have demonstrated the multilineage potential and plasticity of adult stem cells located in periodontal apparatus. However, it remains unclear how epigenetic mechanisms controlling signals determine tissue specification and cell lineage decisions. To date, no data are available on micro-RNA (miRNA) activity behind human-derived dental stem cells (DSCs). MATERIAL AND METHODS: In this study, we isolated periodontal ligament stem cells, dental pulp stem cells and gingival stem cells from extracted third molars; human bone marrow stem cells were used as a positive control. The expression of OCT4A and NANOG was confirmed in these undifferentiated cells. All cells were cultured under osteogenic inductive conditions and RUNX2 expression was analyzed as a marker of mineralized tissue differentiation. The miRNA expression profile was obtained at baseline and after osteogenic induction in all cell types. RESULTS: The expression of RUNX2 demonstrated successful osteogenic induction of all cell types, which was confirmed by alizarin red stain. The analysis of 765 miRNAs demonstrated a shift in miRNA expression that occurred in all four stem cell types, including a decrease in hsa-mir-218 across all differentiated cell populations. Hsa-mir-218 targets RUNX2 and decreases RUNX2 expression in undifferentiated human DSCs. DSC mineralized tissue type differentiation is associated with a decrease in hsa-mir-218 expression. CONCLUSION: These data reveal a miRNA-regulated pathway for the differentiation of human DSCs and a select network of human miRNAs that control DSC osteogenic differentiation.

Opposite effects of high and low frequency rTMS on mood in depressed patients: relationship to baseline cerebral activity on PET.

BACKGROUND: Optimal parameters of rTMS for antidepressant efficacy in general, or within patients, have not been adequately delineated. METHODS: Using a double-blind, sham-controlled, cross-over design, 22 adult patients with treatment refractory major depression (n=9; bipolar disorder, depressed phase) were randomized to active rTMS (20-Hz or 1-Hz) or sham rTMS conditions and given 5 rTMS treatments per week for two weeks. Repetitive TMS was administered at 100% of motor threshold for 1600 pulses over the left prefrontal cortex using a figure-eight coil. Patients initially randomized to sham rTMS were then exposed to two weeks of active rTMS with each frequency under blinded conditions. Those who received active 20-Hz and 1-Hz rTMS were crossed over to the opposite frequency for two weeks. Improvement in Hamilton Depression ratings were assessed after each two-week treatment phase. PET imaging was used to evaluate the patient's baseline absolute regional cerebral activity (blood flow and metabolism) as potential predictor of clinical response. RESULTS: Changes in depression severity on 1-Hz and 20-Hz rTMS were inversely correlated. PET scans with baseline hypoperfusion (but not hypometabolism) were associated with better improvement on 20-Hz rTMS as predicted. LIMITATIONS: The magnitude of the clinical change with either frequency at 100% motor threshold was not robust, and larger studies with higher intensities of rTMS for longer durations of time should be explored. CONCLUSIONS: High and low frequency rTMS exerts differential effects on depressed mood within individual subjects. The brain activity predictors and correlates of an optimal antidepressant response to rTMS remain to be better defined.

Elevated p21 mRNA level in skeletal muscle of DMD patients and mdx mice indicates either an exhausted satellite cell pool or a higher p21 expression in dystrophin-deficient cells per se.

Abnormalities in proliferation and differentiation of the dystrophin-deficient muscle are a controversial aspect of the pathogenesis of Duchenne muscular dystrophy (DMD). Analyses of molecules involved in cell cycle modulation do not exist in this context. Cells withdrawn from the cell cycle permanently express p21. The fact that p2 1, in contrast to other cell cycle proteins, is not diminished when myotubes are reexposed to growth media, allocates this cyclin-dependent kinase inhibitor a special function. Here we report for the first time statistically increased p21 mRNA levels in dystrophin-deficient muscle tissue. Only 42% of conventional RT-PCRs from six muscle samples of human controls yielded positive results but almost all skeletal muscle biopsy samples (87%) from DMD patients (n=5). For p21 mRNA quantification in murine muscle samples we were able to use the exact real-time TaqMan PCR method due to generally higher p21 mRNA levels than in human muscles. In addition, contamination with fibroblasts can be excluded for the murine samples because they do not demonstrate fibrosis at the age of 350 days but start to lose their regenerative capacity. In accord with the results in humans, we observed p21 mRNA levels in mdx mice that were approx. four times as high as those in control mice. Elevated p21 mRNA level may indicate a shift in cell composition towards differentiated p21 expressing cells as a result of an exhausted pool of undifferentiated, non-p21-expressing satellite cells due to previous cycles of de- and regeneration. Alternatively, dystrophin-deficient cells per se may express higher p21 levels for unknown reasons. Although we cannot distinguish between these possibilities, the eventual transfec tion of a patient's own satellite cells with p21 antisense oligonucleotides may enable the dystrophic process to be influenced.

Opposite effects of high and low frequency rTMS on regional brain activity in depressed patients.

BACKGROUND: High (10-20 Hz) and low frequency (1-5 Hz) repetitive transcranial magnetic stimulation (rTMS) have been explored for possible therapeutic effects in the treatment of neuropsychiatric disorders. As part of a double-blind, placebo-controlled, crossover study evaluating the antidepressant effect of daily rTMS over the left prefrontal cortex, we evaluated changes in absolute regional cerebral blood flow (rCBF) after treatment with 1- and 20-Hz rTMS. Based on preclinical data, we postulated that high frequency rTMS would increase and low frequency rTMS would decrease flow in frontal and related subcortical circuits. METHODS: Ten medication-free, adult patients with major depression (eight unipolar and two bipolar) were serially imaged using (15)O water and positron emission tomography to measure rCBF. Each patient was scanned at baseline and 72 hours after 10 daily treatments with 20-Hz rTMS and 10 daily treatments with 1 Hz rTMS given in a randomized order. TMS was administered over the left prefrontal cortex at 100% of motor threshold (MT). Significant changes in rCBF from pretreatment baseline were determined by paired t test. RESULTS: Twenty-hertz rTMS over the left prefrontal cortex was associated only with increases in rCBF. Significant increases in rCBF across the group of all 10 patients were located in the prefrontal cortex (L > R), the cingulate gyrus (L >> R), and the left amygdala, as well as bilateral insula, basal ganglia, uncus, hippocampus, parahippocampus, thalamus, and cerebellum. In contrast, 1-Hz rTMS was associated only with decreases in rCBF. Significant decreases in flow were noted in small areas of the right prefrontal cortex, left medial temporal cortex, left basal ganglia, and left amygdala. The changes in mood following the two rTMS frequencies were inversely related (r = -.78, p <.005, n = 10) such that individuals who improved with one frequency worsened with the other. CONCLUSIONS: These data indicate that 2 weeks of daily 20-Hz rTMS over the left prefrontal cortex at 100% MT induce persistent increases in rCBF in bilateral frontal, limbic, and paralimbic regions implicated in depression, whereas 1-Hz rTMS produces more circumscribed decreases (including in the left amygdala). These data demonstrate frequency-dependent, opposite effects of high and low frequency rTMS on local and distant regional brain activity that may have important implications for clinical therapeutics in various neuropsychiatric disorders.

A cysteine 3340 substitution in the dystroglycan-binding domain of dystrophin associated with Duchenne muscular dystrophy, mental retardation and absence of the ERG b-wave.

We report the first C-terminal missense mutation in a Duchenne muscular dystrophy patient. A G10227A transition of the dystrophin gene was found which resulted in the substitution of a highly conserved cysteine at position 3340 within the second half of the dystroglycan-binding domain. Residual amounts of 427 kDa dystrophin were detected in western blot analysis of the patient's muscle tissue, and immunohistological examination revealed weak traces of dystrophin on all fibers. Sarcolemmal staining intensity of 43 kDa beta-dystroglycan was also reduced. Mental retardation in our patient and absence of the b-wave in his electroretinogram indicate that central nervous functions of dystrophin isoforms also depend on the presence of cysteine 3340.

Evidence for quiescent S- and G2-phase cells in human colorectal carcinomas: a flow cytometric study with the Ki-67 antibody.

The expression of certain antigens specific for proliferating cells can be determined simultaneously with cell cycle distribution by means of two-dimensional flow cytometry. In this way, a tumour's growth potential is characterized more precisely than with any one parameter alone. Here we describe such simultaneous measurements of DNA content and labelling with the Ki-67 antibody that distinguishes between cycling and non-cycling cells. Having overcome a number of technical problems we were able to analyse material from 29 biopsies of human colorectal tumours. In a number of cases, Ki-67 negative cells were found with a DNA-content of G0/1 only, whereas all cells with an S- or G2-phase DNA-content were Ki-67 positive. There were other cases in which cells with an S- and G2-phase DNA-content had obviously become quiescent (Ki-67 negative), sometimes even outnumbering the proliferating (Ki- 67 positive) cells in the respective compartments of the cycle. Generally, however, when Ki-67 negative and positive subpopulations were analysed separately it was found that the former had a significantly lower (S + G2)-phase fraction than the latter. There was evidence for a correlation between Ki-67 index and (S + G2)-phase fraction at least in the subgroup of aneuploid tumours. Neither of the two parameters was correlated with stage according to Duke's classification or tumour size. However, a positive correlation was found between the fraction of unlabelled S- and G2-phase cells and tumour size as reflected in the T category.

Prenatal diagnosis of the acute form of proximal spinal muscular atrophy: experience on the acceptance of linkage analyses by the families.

The acute form of proximal spinal muscular atrophy (SMA) is a severe autosomal recessive inherited neuromuscular disorder. It has been mapped to chromosome 5q 11.2-13.3. Using restriction fragment length polymorphisms (RFLPs) or (CA)n repeats of DNA probes in this region, prenatal diagnosis is, in principle, possible. Misdiagnosis can be due to incorrect diagnosis in the index patient, and crossing-over events. Using the DNA probes D5S6, D5S112, D5S39, and D5S78, we cover a region of 10.4 mega-base pairs (Mbp) of partially NotI-digested genomic DNA without overlap of fragments. The DNA probes D5S6 and D5S112, most likely flanking the SMA gene, cover a distance of about 6.6 Mbp. This corresponds to the genetic distance of 6 cM (Morrison et al., 1992; Daniels et al., 1992). But since the precise localization of the SMA gene is still unknown (Simard et al., 1992), a 10 per cent risk of misdiagnoses due to crossing-over events cannot be excluded. The acceptance of this 10 per cent risk for prenatal diagnoses differs in SMA families. We observed a case in which a woman accepted a 25 per cent risk because RFLPs and (CA)n repeats were both uninformative. In contrast, another family did not accept the minimal 10 per cent risk and the pregnancy was terminated. In two families, we performed prenatal diagnosis by linkage analysis. One child predicted to be healthy has been born in the meantime and has shown no indication of SMA during her first 8 months.

[The development of molecular human genetics and its significance for perspectives of modern medicine]. / Die Entwicklung der molekularen Humangenetik und ihre Bedeutung für die perspektive der modernen Medizin.

The introduction of molecular human genetics has become a paradigma for the application of genetic engineering in medicine. The main principles of this technology are the isolation of molecular probes, their application in hybridization reactions, specific gene-amplification by the polymerase chain reaction, and DNA sequencing reactions. These methods are used for the analysis of monogenic diseases by linkage studies and the elucidation of the molecular defect causing these conditions, respectively. They are also the basis for genomic diagnosis of monogenic diseases, introduced into the health care system of the GDR by a national project on Duchenne/Becker muscular dystrophy, Cystic Fibrosis and Phenylketonuria. The rapid development of basic research on the molecular analysis of the human genome and genomic diagnosis indicates, that human molecular genetics is becoming a decisive basic discipline of modern medicine.

Endoscopic management of malignant biliary obstruction: stents of 10 French gauge are preferable to stents of 8 French gauge.

To assess whether the use of large stents is justified, we have retrospectively reviewed the results of 8 French gauge (FG) stents with pigtails and 10 FG straight stents in the palliation of biliary obstruction due to malignancy. The incidence of cholangitis following stent insertion was significantly lower with 10 FG stents, 3 (5%), compared with 8 FG stents, 13 (34%), p less than 0.001, chi 2. Stent survival until blockage was significantly longer for 10 FG (median 32 weeks) compared with 8 FG (median 12 weeks), p less than 0.001, log-rank. The superior performance of the 10 FG stents was due to their larger diameter which gives them a flow capacity much greater than the physiological bile flow. We recommend that stents of at least 10 FG diameter are used for the endoscopic palliation of biliary obstruction due to malignancy.

Extracorporeal shock-wave lithotripsy and the management of common bile-duct calculi.

Endoscopic sphincterotomy is the treatment of first choice for stones that remain in the bile duct after cholecystectomy. There is a small group of patients in whom this technique is not successful; many of these patients carry a high risk for surgery because of their age or associated medical conditions. A variety of non-surgical techniques is available; however, none is well established. We have used an in-vitro model to show that human gallstones are fragmented readily by shock-wave lithotripsy. Two elderly frail patients with difficult bile-duct stones have been treated successfully by extracorporeal shock-wave lithotripsy. The bile ducts were cleared of stones and the patients suffered no adverse effects. Extracorporeal shock-wave lithotripsy is a new and promising alternative to the current non-surgical techniques for the management of bile-duct stones.

Biliary stent blockage with bacterial biofilm. A light and electron microscopy study.

Clogging of endoscopic stents necessitates their replacement in many patients with malignant obstructive jaundice and limits their use in benign strictures. We studied the basic mechanism of clogging to find ways to prevent it. We did light and electron microscopy studies of blocked and functioning stents, which were prepared so that organic structures would be preserved. The material blocking the lumina was composed of a matrix of bacterial cells and their fibrillar anionic extracellular products. Crystals of calcium bilirubinate, calcium palmitate, and cholesterol were embedded within this matrix. Bacterial cells were attached to the stent surface by a fibrillar matrix, suggesting that the initial event in stent clogging is the development of an adherent bacterial biofilm. Bacterial enzyme activity (beta-glucuronidase and phospholipase) leads to the deposition of crystals. The use of antibacterial plastics in the manufacture of stents may reduce bacterial adhesion and stent clogging.