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61.
Retrograde intubation is part of the difficult airway algorithm in the American Society of Anesthesiologists, but its usage is rare in small pediatric patients with the advent of new intubation techniques. We present our experience of retrograde intubation for a 4-month-old patient who presented for laryngeal cleft repair on cardiopulmonary bypass. This case highlights the unique place for retrograde intubation in small patients in the current era.  相似文献   
62.
Objectives: To analyze the relationship between six polymorphisms in genes related to oxidative stress, namely CAT-262 C>T, MnSOD Ala16Val, GPX1 Pro198Leu, GSTM1 and GSTT1 null genotypes, and GSTP1 Ile105Val, and the occurrence of BCR-ABL negative myeloproliferative neoplasms (polycythemia vera, essential thrombocythemia, and primary myelofibrosis).

Methods: We genotyped for these polymorphisms 328 patients with a known mutation status for JAK2 V617F, MPL and CALR, and 363 controls, using molecular genetics assays.

Results: The CAT-262 C>T and GPX1 Pro198Leu polymorphisms were seen significantly less frequently, while the GSTP1 IleVal105 polymorphism was seen significantly more frequently in patients with BCR-ABL negative myeloproliferative neoplasms, regardless of the molecular sub-type (e.g. JAK2 V617F or CALR mutated).

Discussion and conclusion: Our study provides evidence that variation in genes related to oxidative stress might modulate the risk of developing BCR-ABL negative myeloproliferative neoplasms.  相似文献   
63.
Plastic bronchitis (PB) is an uncommon, potentially fatal disease, marked by endobronchial cast formation causing variable degrees of respiratory distress. Primary and secondary pulmonary lymphatic abnormalities have been identified among the underlying mechanisms of cast formation. We present a case of PB where lymphoscintigraphy demonstrated the underlying lymphatic defect. A 6‐year‐old Hispanic male with congenital heart disease (CHD; post‐Fontan) presented with recurrent pneumonia, respiratory distress. Bronchoscopy showed inflamed hypervascular mucosa and thick mucus plugs; no casts were seen. Later, PB was diagnosed after the patient expectorated a bronchial cast. Cast analysis showed lymphocytic aggregates with mucin and fibrin. Lymphoscintigraphy revealed abnormal lymphatic collaterals and retrograde trace reflux into the superior mediastinum, a picture consistent with thoracic duct lymph leakage into the tracheobronchial tree. The pathogenesis of PB is not fully understood, especially in patients with CHD. Chyle in bronchial casts suggests abnormal lymphatic flow. Reports of lymph flow abnormalities, especially endobronchial lymph leakage in CHD are limited. Lymphoscintigraphy in our case demonstrated clear evidence of retrograde lymph reflux and leakage into the bronchial tree. The case presented suggests that in some patients following Fontan surgery, high intrathoracic lymphatic pressure and retrograde lymph flow may contribute to recurrent cast formation. Finding the underlying lymphatic abnormality helps in specific case management. Lymphoscintigraphy is a safer and easier method than lymphangiography. Surgical lymphatic–venous shunting may be possible in select cases. Pediatr Pulmonol. 2013; 48:515–518. © 2012 Wiley Periodicals, Inc.  相似文献   
64.
Positron emission tomography (PET) is becoming an important tool for the investigation of emerging infectious diseases in animal models. Usually, PET imaging is performed after intravenous (IV) radiotracer administration. However, IV injections are difficult to perform in some small animals, such as golden hamsters. This challenge is particularly evident in longitudinal imaging studies, and even more so in maximum containment settings used to study high-consequence pathogens. We propose the use of intramuscular (IM) administration of 2-deoxy-2[18F]fluoro-D-glucose ([18F]F-FDG) for PET imaging of hamsters in a biosafety level 4 (BSL-4) laboratory setting. After [18F]F-FDG administration via IM or IV (through surgically implanted vascular access ports), eight hamsters underwent static or dynamic PET scans. Time–activity curves (TACs) and standardized uptake values (SUVs) in major regions of interest (ROIs) were used to compare the two injection routes. Immediately after injection, TACs differed between the two routes. At 60 min post-injection, [18F]F-FDG activity for both routes reached a plateau in most ROIs except the brain, with higher accumulation in the liver, lungs, brain, and nasal cavities observed in the IM group. IM delivery of [18F]F-FDG is an easy, safe, and reliable alternative for longitudinal PET imaging of hamsters in a BSL-4 laboratory setting.  相似文献   
65.
On May 3, 2008, a National Cancer Institute (NCI)-sponsored open consensus conference was held in Toronto, Ontario, Canada, during the 2008 International Society for Magnetic Resonance in Medicine Meeting. Approximately 100 experts and stakeholders summarized the current understanding of diffusion-weighted magnetic resonance imaging (DW-MRI) and reached consensus on the use of DW-MRI as a cancer imaging biomarker. DW-MRI should be tested as an imaging biomarker in the context of well-defined clinical trials, by adding DW-MRI to existing NCI-sponsored trials, particularly those with tissue sampling or survival indicators. Where possible, DW-MRI measurements should be compared with histologic indices including cellularity and tissue response. There is a need for tissue equivalent diffusivity phantoms; meanwhile, simple fluid-filled phantoms should be used. Monoexponential assessments of apparent diffusion coefficient values should use two b values (> 100 and between 500 and 1000 mm2/sec depending on the application). Free breathing with multiple acquisitions is superior to complex gating techniques. Baseline patient reproducibility studies should be part of study designs. Both region of interest and histogram analysis of apparent diffusion coefficient measurements should be obtained. Standards for measurement, analysis, and display are needed. Annotated data from validation studies (along with outcome measures) should be made publicly available. Magnetic resonance imaging vendors should be engaged in this process. The NCI should establish a task force of experts (physicists, radiologists, and oncologists) to plan, organize technical aspects, and conduct pilot trials. The American College of Radiology Imaging Network infrastructure may be suitable for these purposes. There is an extraordinary opportunity for DW-MRI to evolve into a clinically valuable imaging tool, potentially important for drug development.  相似文献   
66.
Breast cancer among Palestinian women has lower incidence than in Europe or North America, yet is very frequently familial. We studied genetic causes of this familial clustering in a consecutive hospital‐based series of 875 Palestinian patients with invasive breast cancer, including 453 women with diagnosis by age 40, or with breast or ovarian cancer in a mother, sister, grandmother or aunt (“discovery series”); and 422 women diagnosed after age 40 and with negative family history (“older‐onset sporadic patient series”). Genomic DNA from women in the discovery series was sequenced for all known breast cancer genes, revealing a pathogenic mutation in 13% (61/453) of patients. These mutations were screened in all patients and in 300 Palestinian female controls, revealing 1.0% (4/422) carriers among older, nonfamilial patients and two carriers among controls. The mutational spectrum was highly heterogeneous, including pathogenic mutations in 11 different genes: BRCA1, BRCA2, TP53, ATM, CHEK2, BARD1, BRIP1, PALB2, MRE11A, PTEN and XRCC2. BRCA1 carriers were significantly more likely than other patients to have triple negative tumors (p = 0.03). The single most frequent mutation was TP53 p.R181C, which was significantly enriched in the discovery series compared to controls (p = 0.01) and was responsible for 15% of breast cancers among young onset or familial patients. TP53 p.R181C predisposed specifically to breast cancer with incomplete penetrance, and not to other Li‐Fraumeni cancers. Palestinian women with young onset or familial breast cancer and their families would benefit from genetic analysis and counseling.  相似文献   
67.
An important cause of intestinal bleeding in patients with chronic renal failure is angiodysplasia. In retrospective reports up to 19-32% of patients had bleeding from angiodysplastic lesions. These are usually multiple, have a high tendency of rebleeding (25-47%) and are often located in the stomach and duodenum, but can affect the colon and the jejunum as well. Bleeding from angiodysplastic lesions is usually low grade and stops spontaneously in more than 90% of patients, but some times may be life threatening necessitate therapeutic interventions to achieve hemostasis. We report a case of an 18-year old female with renal failure on CAPD who presented a massive lower gastrointestinal bleeding and imposed emergency surgery.  相似文献   
68.
Liver hydatid disease still represents a frequent condition in Romania, especially among population of Dobrogea County, which may lead to life-threatening complications. To assess the role of intraoperative ultrasound (IOUS) in the diagnosis and treatment algorithms of liver hydatid disease. We could not find any similar studies in the literature in order to compare the results. The paper represents a retrospective study of IOUS performed for liver hydatid disease on a group of 43 patients admitted in the 2nd Clinic of Surgery - Clinical Emergency Hospital of Constanta. IOUS was intraabdominal (36 cases), transdiaphragmatic (7 cases) and was able to diagnose infected liver HC (7 cases), locate bilio-cystic fistulas (6 cases), hydatic cysts (18 cases) or relation with important anatomic elements (12). Ultrasound-guided frenotomy was performed in 5 cases and ultrasound-guided puncture in 9 cases. In 26 out of 43 patients (60.47%), IOUS influenced decision making during surgery. These data recommends IOUS in managing hydatid disease, allowing a complete diagnosis and optimal treatment, thus reducing postoperative morbidity.  相似文献   
69.
70.
Discogenic pain has been responsible for a countless number of missed workdays and millions if not billions of dollars of lost revenue. Minimally invasive interventional therapies of the discogenic back pain gained significant acceptance among the proceduralists. The centuries old dilemma of discogenic low back pain has by no means been answered. We know today that discogenic low back pain has a multitude of causes. The leaking "chemical soup" within the nucleus pulposus is certainly responsible for causing inflammation and thus pain. However, neuropeptides released from peripheral endings of nociceptive afferents are also inflammatory mediators and pain generators. The nerves innervating the discs have been identified and in many cases denervated with good results. These nerves from posterior to anterior include the sinuvertebral nerve, the rami communicantes, and the sympathetic trunk. Diagnosing discogenic low back pain is the key to successful treatment. Classically this should be a low back pain in a "band-like" distribution without radiculopathy that is worse in the morning, worse with Valsalva, and aggravated by standing in flexion. Provocative discography with manometric monitoring is essential in aiding the diagnosis. Once the diagnosis is confirmed, a multitude of invasive therapy may be offered including: L2 root sleeve blocks, intradiscal RFTC, RFTC of the rami communicantes, or Comparative data on the effectiveness of the above-mentioned procedures is lacking and may in fact be an excellent topic for future discussion.  相似文献   
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