Whole body proton irradiation causes acute damage to bone marrow hematopoietic progenitor and stem cells in mice

Purpose: Exposure to proton irradiation during missions in deep space can lead to bone marrow injury. The acute effects of proton irradiation on hematopoietic stem and progenitor cells remain undefined and thus were investigated.

Materials and methods: We exposed male C57BL/6 mice to 0.5 and 1.0?Gy proton total body irradiation (proton-TBI, 150?MeV) and examined changes in peripheral blood cells and bone marrow (BM) progenitors and LSK cells 2 weeks after exposure.

Results: 1.0?Gy proton-TBI significantly reduced the numbers of peripheral blood cells compared to 0.5?Gy proton-TBI and unirradiated animals, while the numbers of peripheral blood cell counts were comparable between 0.5?Gy proton-TBI and unirradiated mice. The frequencies and numbers of LSK cells and CMPs in BM of 0.5 and 1.0?Gy irradiated mice were decreased in comparison to those of normal controls. LSK cells and CMPs and their progeny exhibited a radiation-induced impairment in clonogenic function. Exposure to 1.0?Gy increased cellular apoptosis but not the production of reactive oxygen species (ROS) in CMPs two weeks after irradiation. LSK cells from irradiated mice exhibited an increase in ROS production and apoptosis.

Conclusion: Exposure to proton-TBI can induce acute damage to BM progenitors and LSK cells.     

Unilaterally and rapidly progressing white matter lesion and elevated cytokines in a patient with Tay–Sachs disease

We report the case of a girl with Tay–Sachs disease who had convulsions and deteriorated rapidly after an upper respiratory infection at the age of 11 months. At the age of 16 months, her seizures became intractable and magnetic resonance imaging of the brain showed high signal intensity on T2-weighted images and marked swelling in the white matter and basal nucelei of the right hemisphere. Her seizures and right hemisphere lesion improved with glycerol and dexamethasone treatment. When dexamethasone was discontinued, her symptoms worsened and lesions later appeared in the left hemisphere. Her cerebrospinal fluid showed elevated levels of the cytokines TNF-α and IL-5. It is considered that inflammation contributes to disease progression in Tay–Sachs disease.     

The benefits of laparoscopic appendectomies in obese patients

BackgroundSystematic reviews and randomized controlled trials comparing laparoscopic appendectomy (LA) with open appendectomy (OA) show a reduction in wound infections associated with LA but a 3-fold increase in intra-abdominal abscess with LA. Surgical time and operation costs are higher with LA. The advantage of LA over OA is small. Although these patients have not been specifically analyzed in the report, the systematic review recommends the routine use of LA in young women and obese people. The purpose of this study is to determine if obese patients benefit in a shorter length of stay (LOS) by having LA versus OA surgery compared with their nonobese counterparts.MethodsA retrospective chart review of 315 adult patients who have undergone appendectomies at Royal Columbian and Burnaby Hospitals between April 1, 2010 and March 31, 2011. Appendectomies performed in pregnant women combined with other surgeries and those converted to OA were excluded. Outcomes and the postoperative stay for obese and nonobese patients were assessed.ResultsThe LOS is shorter with LAs than with OAs (2.06 vs 4.13 days, P < .05). The LOS, in obese patients, is much shorter with LAs than with OAs (1.69 vs 6.82 days, P < .05). The variability in LOS is much higher in obese patients as compared with nonobese patients (standard deviation = 8.57 vs 2.67). The body mass index and the type of surgery contribute to a significant difference in LOS.ConclusionsObese patients who undergo LA have a decreased LOS as compared with obese patients who undergo OA for appendicitis. This is the first study showing specifically that LA benefits obese patients and the health care system.     

Renal arterial resistive index response to intraabdominal hypertension in a porcine model

OBJECTIVE: The abdominal compartment syndrome is a potentially life-threatening condition with frequent renal involvement. There are few if any means of inferring subclinical effects before organ dysfunction. Because intrarenal pressure correlates with renal sonographic indices in other renal diseases, the purpose of this study was to determine the relationship between increasing intraabdominal hypertension and renal vascular flow velocities in a porcine model using renal Doppler ultrasound. DESIGN: Animal study. SETTING: University research laboratory. SUBJECTS: Eight anesthetized, mechanically ventilated, well-hydrated, 30-kg female Yorkshire pigs. INTERVENTIONS: Intraabdominal hypertension was induced by instillation of warmed intraperitoneal saline through a midline laparoscopic port. Intraabdominal pressure (IAP) was continuously monitored directly from the peritoneum and indirectly from the bladder. IAP was varied from 0 to 50 mm Hg in increments of 5 mm Hg. At each IAP level, gray-scale, color, and spectral Doppler renal arcuate artery ultrasound was obtained and resistive index (RI) and peak airway pressure calculated. MEASUREMENTS AND MAIN RESULTS: Excellent agreement between direct and indirect IAP was found (bias, 0.032 mm Hg; 95% limits, -5.5 to 5.6 mm Hg). A linear relationship between RI and indirect IAP was observed and was defined by the regression equation: RI = 0.553 + 0.0104 x bladder pressure. There was a trend toward different RIs between left and right kidneys (p = .052) at the same IAP. RI varied in a linear fashion at low peak airway pressure and demonstrated an inflection point with steeper subsequent slope after peak airway pressure of 30 cm H2O. RI values rapidly returned to near baseline after abdominal decompression. CONCLUSIONS: In this model, the renal artery RI correlated strongly and linearly with the severity of intraabdominal hypertension, making renal Doppler ultrasound a potential noninvasive screening tool for the renal effects of intraabdominal hypertension. Further studies are warranted.     

Endoscopic Findings and Clinical Manifestation of Gastric Anisakiasis

Objectives : To identify the endoscopic findings and clinical manifestations of anisakiasis, we studied 87 cases of gastric anisakiasis. Methods : Patient information was analyzed by means of patient records. The interval between the day of intake of Anisakis and endoscopic examination was determined in 86 cases. Then the endoscopic findings of each interval were elucidated. Results : Moderate to severe gastric mucosal edema tends to occur within 1 or 2 days after Anisakis infection, accompanied by leukocytosis. As to the sites of penetration of Anisakis, 55 % of cases were found in the greater curvature with severe mucosal edema. Among 87 cases, four patients experienced anisakiasis twice during the interval examined, and six patients had past histories of anisakiasis before the investigated interval. Conclusions : Gastric anisakiasis may be caused by an allergic reaction to the Anisakis antigen. There is a classic relationship between clinical and endoscopic findings and the interval after Anisakis administration. Anisakis usually is found in the greater curvature.