Correlation of radiographic and endoscopic evaluation of gastrojejunal anastomosis after Roux-en-Y gastric bypass.

BACKGROUND: Anastomotic stenosis presents as one of the most common late complications in the postoperative period after bariatric surgery. It is often diagnosed by upper gastrointestinal series (UGIS) and/or upper endoscopy (UE). The aim of this study was to determine whether a correlation exists between the Gastrografin UGIS and UE findings in the determination of gastrojejunal anastomotic strictures after Roux-en-Y gastric bypass (RYGB). METHODS: Between July 2001 and October 2003, all medical records of patients who underwent RYGB at our institution were retrospectively reviewed. The medical records of patients who underwent UE because of symptoms suggestive of gastric outlet obstruction and those of patients who were initially evaluated by Gastrografin UGIS before UE were evaluated further. RESULTS: Of 535 morbidly obese patients who underwent RYGB, 52 (9.7%) had UE and were included in this study. The mean number of UEs performed per patient was 2.67. Of these 52 patients, 30 underwent Gastrografin UGIS before UE. The mean diameter of the anastomosis on the first UE was 5.97 mm and on Gastrografin UGIS was 6.83 mm. A good correlation was found between the Gastrografin UGIS and UE findings using Pearson's correlation coefficient (0.44, P = .02) and single linear regression analysis using the endoscopic diameter as the outcome and radiographic findings as the predictor (beta = 0.27, P = .025, 95% confidence interval 0.30-0.49). CONCLUSION: In our study, the Gastrografin UGIS findings correlated positively with the endoscopic gastrojejunal anastomosis findings in patients with anastomotic stricture who had undergone RYGB.     

Genetic testing for hearing loss: different motivations for the same outcome

Autism is a complex genetic disorder. Chromosome 15 is of particular interest in this disorder, because of previous reports of individuals with autism with chromosomal abnormalities in the 15q11-q13 region. Transmission disequilibrium between polymorphisms in this region and autism has been also been reported in some, but not all studies. Recently, a novel maternally expressed gene, ATP10C, was characterized and mapped to the chromosome 15q11-q13 region, 200 kb distal to UBE3A. It encodes a putative aminophospholipid translocase likely to be involved in the asymmetric distribution of proteins in the cell membrane. Preferential maternal expression has been demonstrated in fibroblasts and brain. Because of its physical location and imprinting pattern, ATP10C was considered to be a candidate gene for chromosome 15-associated autism. In an effort to find the genes responsible for autism in this chromosomal region, 1.5 kb of the 5' flanking region, as well as the coding and splicing regions of ATP10C, were screened for sequence variants. Several polymorphic markers including five nonsynonymous SNPs were identified. To investigate transmission disequilibrium between ATP10C and autism, a family-based association study was conducted for 14 markers in 115 autism trios. No significant transmission disequilibrium was found, suggesting ATP10C is unlikely to contribute strongly to susceptibility to autism in these families. However, due to limited power to detect genes of modest effect, the possible functional role of the nonsynonymous SNPs and the functional implications of the SNPs identified from 5' flanking region and intron 2 splicing region may be evaluated in further studies.     

Inhibition of host cell catalase by Mycoplasma pneumoniae: a possible mechanism for cell injury.

This study demonstrates that viable Mycoplasma pneumoniae cells inhibit catalase activity in several types of intact human cells as well as in solution. Human erythrocyte catalase was inhibited up to 72%, and the inhibition of catalase in human cultured skin fibroblasts, lung carcinoma epithelial cells, and ciliated epithelial cells from human nasal polyps ranged between 75 and 80%. UV light-killed mycoplasmas failed to inhibit catalase activity both in intact cells and in vitro. After M. pneumoniae infection of human cultured skin fibroblasts, the level of malonyldialdehyde, an indicator for membrane lipid peroxidation, was 3.5 times higher than in control fibroblasts. Virulent M. pneumoniae completely inhibited catalase activity in solution, whereas the nonvirulent strains had a lesser ability to inhibit catalase activity. These findings suggest that as a result of host cell catalase inhibition by M. pneumoniae, the toxicity of the hydrogen peroxide generated by the microorganism and the affected cell is enhanced, thereby inducing host cell damage.     

Immune-deficient SCID and NOD/SCID mice models as functional assays for studying normal and malignant human hematopoiesis

 Many events and requirements of the developmental program of human hematopoietic stem cells have not yet been discovered. A major impediment has been the lack of an appropriate experimental system. At present the conditions for maintaining human stem cells in vitro are not fully known. As a result within a short period the small stem cell pool is lost due to differentiation, making it difficult to examine the correlation between these cells and their function in vivo. Most of our knowledge of hematopoietic stem cells is from animal models in which purified stem cell canididates are assayed based on their functional ability to rescue lethally conditioned recipients. The permanent correction of many genetic disorders of the hematopoietic system requires efficient methods for introducing genes into stem cells in vitro. However, progress has been hindered by the absence of preclinical models that assay the repopulating capacity of primitive human cells. In addition, the development of therapy for malignant diseases also requires assays to identify the target leukemic stem cells based on their ability to initiate the disease. The recent development of methods to transplant or implant both normal and leukemic cells into immune-deficient mice provides the foundation for human stem cell assays. These models assay the repopulating capacity of primitive human cells and provide an important approach to identify and characterize human stem cells, both normal and leukemic. This review focuses on the development of functional assays for normal and leukemic human stem cells and on the new insights that these models are beginning to provide on the organization of the human stem cell hierarchy. Received: 27 January 1997 / Accepted: 3 April 1997     

The Effect of Presleep Focal Attention Load on Subsequent Sleep Patterns

The hypothesis that a load on focal attention prior to sleep results in subsequent changes in sleep patterns was investigated. Eight females and 2 males slept in the laboratory for 4 nights: 2 adaptation nights, 1 experimental night preceded by a focal attention load, and 1 control night preceded by relaxed activity. On the experimental night, time in bed, total sleep time, and stage REM sleep were significantly longer than on the control night. The results support the hypothesis and suggest that attention during REM sleep has a unique character.     

Checkpoint Blockade Immunotherapy Induces Dynamic Changes in PD-1−CD8+ Tumor-Infiltrating T Cells

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Neonatal hyperthyrotropinemia: population characteristics,diagnosis, management and outcome after cessation of therapy

Introduction Neonatal hyperthyrotropinaemia (HT), defined by elevated TSH and normal T₄, is either transient or persistent. The eventual outcome of neonatal HT is unpredictable and the management of HT patients is controversial. We assessed perinatal parameters and diagnostic measures that may distinguish between transient and persistent HT, compared with congenital hypothyroidism (CH). We also aimed to recommend optimal treatment in these forms of thyroid impairment. Design and patients A multi‐centre, retrospective study was conducted in six paediatric endocrinology units. Forty‐three HT patients and 83 CH patients were included in the study. Measurements We evaluated differences in birth weight (BW), gestational age (GA), modes of diagnosis, screening and confirmatory T₄ and TSH levels, thyroid imaging results and optimal thyroxine doses between HT and CH and between the two forms of HT. Results Newborns with HT had lower BW and GA than those with CH. Transient (n = 18) and persistent HT (n = 25) patients were indistinguishable by most parameters, but those with persistent HT had a higher prevalence of abnormal thyroid imaging (69%vs 8%; P = 0·005). During treatment, 79% and 55% of transient and persistent HT patients respectively experienced elevated levels of free T_4. Although most HT patients were reevaluated after 2·5 years, six transient HT patients stopped therapy and showed full recovery within the first year of life. Conclusions We recommend obtaining thyroid imaging to distinguish between the two forms of HT. Adherence to recommended doses of thyroxine and probably early cessation of therapy in transient HT can prevent iatrogenic hyperthyroidism in these patients.     

Functional magnetic resonance imaging monitoring of pathological changes in rodent livers during hyperoxia and hypercapnia

Liver diseases and regeneration are associated with hemodynamic changes denoting pathological alterations. Determining and monitoring physiological and pathological liver changes is essential for diagnostic and therapeutic objectives. Our aim was to determine the feasibility of functional magnetic resonance imaging (fMRI) during hypercapnia and hyperoxia for monitoring liver pathology. Liver fMRI images were acquired in rodents following acute bleeding, partial hepatectomy, and fibrosis. Results were quantitated and confirmed by histology. Changes induced by hyperoxia and hypercapnia following hemorrhage significantly correlated with the percentage of blood loss, reflecting lower liver perfusion and diminished vessel responsiveness to gas saturation. Hepatectomy resulted in an early decline in signal intensity changes due to hyperoxia, suggesting a decrease in liver perfusion and blood content. Following hepatectomy, signal intensity changes due to hypercapnia increased, signifying a change in liver perfusion from a mainly portal to a more arterial source. Two weeks after induction of fibrosis, signal intensity changes due to hypercapnia became much lower and those due to hyperoxia were much higher than those in normal livers, reflecting the increased perfusion due to the inflammatory process as confirmed by histologic analysis. With fibrosis progression, signal intensity changes induced by hypercapnia and hyperoxia were gradually attenuated, indicating structural and functional alterations of the liver vasculature during fibrosis. CONCLUSION: In various liver pathologies, fMRI response to hypercapnia and hyperoxia is sensitive to changes in liver hemodynamic status involved in hepatic damage or recovery; thus, this technique may offer an additional noninvasive diagnostic tool for evaluation and follow-up of liver diseases by means of examining perfusion-related alterations.     

High rates of depressive symptoms among patients with systemic sclerosis are not explained by differential reporting of somatic symptoms

OBJECTIVE: Between 36% and 65% of patients with systemic sclerosis (SSc) report symptoms of depression above cutoff thresholds on self-report questionnaires. The objective of this study was to assess whether these high rates result from differential reporting of somatic symptoms related to the high physical burden of SSc. METHODS: Symptom profiles reported on the Center for Epidemiologic Studies Depression Scale (CES-D) were compared between a multicenter sample of 403 patients with SSc and a sample of respondents to an Internet depression survey, matched on total CES-D score, age, race/ethnicity, and sex. An exact nonparametric generalized Mantel-Haenszel procedure was used to identify differential item functioning between groups. RESULTS: Patients with SSc reported significantly higher frequencies (moderate to large effect size; P < 0.01) on 4 CES-D somatic symptom items: bothered, appetite, effort, and sleep. Internet respondents had higher item scores on 2 items that assessed interpersonal difficulties (unfriendly, large effect size; P < 0.01; disliked, large effect size; P < 0.01) and on 2 items that assessed lack of positive effect (happy, moderate effect size; P = 0.01; enjoy, large effect size; P < 0.01). Adjustment of standard CES-D cutoff criteria for potential bias due to somatic symptom reporting resulted in a reduction of only 3.6% in the number of SSc patients with significant symptoms of depression. CONCLUSION: High rates of depressive symptoms in SSc are not due to bias related to the report of somatic symptoms. The pattern of differential item functioning between the SSc and Internet groups, however, suggests some qualitative differences in depressive symptom presentation.