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81.
82.
In this study, we used real-time PCR to simultaneously monitor the responses of 12 key genes of the shrimp innate immune system in Litopenaeus vannamei after challenge with Vibrio harveyi. In the proPO activating system, we found that proPO was up-regulated (3.3× control at 36 hpi). The hemolymph clotting genes transglutaminase (TGase) and clotting protein were also up-regulated, as were 5 genes in the antimicrobial peptide system (ALF, Crustin, Lyz, PEN2 and PEN4), with only PEN3 showing no significant changes. In the antioxidant defense system, SOD was slightly elevated while GPx was substantially down-regulated. In the pattern recognition receptor system, at 24 hpi, the Toll gene (LvToll) showed the highest relative increase in expression level of all the investigated genes (15× greater than the sterile seawater control). In the second part of this study, when LvToll was knocked down by RNAi silencing, there was no effect on either survival rates or bacterial number in unchallenged shrimp. There was also no difference in mortality rates between control shrimp and LvToll-silenced shrimp when these two groups were challenged with a viral pathogen (white spot syndrome virus; WSSV). However, when LvToll-silenced shrimp were challenged by V. harveyi, there was a significant increase in mortality and bacterial CFU counts. We note that the increase in bacterial CFU count occurred even though treatment with EGFP dsRNA had the opposite effect of reducing the CFU counts. We conclude that LvToll is an important factor in the shrimp innate immune response to acute V. harveyi infection, but not to WSSV.  相似文献   
83.
Tissue microarrays (TMAs) have become an invaluable tool in cancer research to evaluate expression and subcellular localization of proteins in cells and tissues. As the catalogs of candidate biomarkers and therapeutic targets become more extensive, there is a need to characterize and validate these targets and biomarkers in cell lines as a primary biological system in research laboratories. Thus, cell microarrays (CMAs) are useful as a high-throughput screening tool. Here, we constructed a CMA containing 32 publicly available immortalized breast cell lines with the goal of creating a method to rapidly screen for antigens of interest in breast cancer research in a relatively easy, rapid and cost-effective manner. As proof of concept, we performed immunocytochemical staining of the HER2 receptor, as the status of this protein is relevant to breast cancer and has previously been reported for these cell lines. We observed a complete concordance of our staining with the published status of HER2 in these cell lines. In addition, we examined the expression of CD44, epithelial markers EpCAM and E-cadherin and tyrosine phosphoproteins. The labeling of these proteins correlates with the known biology of the cell lines. Our results demonstrate the utility of our method to screen for potential biomarkers and therapeutic targets in breast cancer and we suggest that CMAs be used as a general approach in breast cancer research.  相似文献   
84.
As your hospital's ICU director, you are approached by the hospital's administration to help solve ongoing problems with ICU bed availability. The ICU seems to be constantly full, and trauma patients in the emergency department sometimes wait up to 24 hours before receiving a bed. Additionally, the cardiac surgeons were forced to cancel several elective coronary-artery bypass graft cases because there was not a bed available for postoperative recovery. The hospital administrators ask whether you can decrease your ICU length of stay, and wonder whether they should expand the ICU to include more beds For help in understanding and optimizing your ICU's throughput, you seek out the operations management researchers at your university.  相似文献   
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86.
Background

Almost all preventable neonatal deaths take place in low- and middle-income countries and affect the poorest who have the least access to high quality health services. Cost of health care is one of the factors preventing access to quality health services and universal health coverage. In Nepal, the majority of expenses related to newborn care are borne by the caregiver, regardless of socioeconomic status. We conducted a study to assess the out of pocket expenditure (OOPE) for sick newborn care in hospitals in Nepal.

Methods

This cross-sectional study of hospital care for newborns was conducted in 11 hospitals in Nepal and explored OOPE incurred by caregivers for sick newborn care. Data were collected from the caregivers of the sick newborn on the topics of cost of travel, accommodation, treatment (drugs, diagnosis) and documented on a sick newborn case record form.

Results

Data were collected from 814 caregivers. Cost of caregivers’ stay accounted for more than 40% of the OOPE for sick newborn care, followed by cost of travel, and the baby’s stay and treatment. The overall OOPE ranged from 13.6 to 226.1 US dollars (USD). The median OOPE was highest for preterm complications ($33.2 USD; CI 14.0–226.1), followed by hyperbilirubinemia ($31.9 USD; CI 14.0–60.7), respiratory distress syndrome ($26.9 USD; 15.3–121.5), neonatal sepsis ($ 25.8 USD; CI 13.6–139.8) and hypoxic ischemic encephalopathy ($23.4 USD; CI 13.6–97.7).

Discussion for practice

In Nepal, OOPE for sick newborn care in hospitals varied by neonatal morbidity and duration of stay. The largest proportion of OOPE were for accommodation and travel. Affordable and accessible health care will substantially reduce the OOPE for sick newborn care in hospitals.

  相似文献   
87.
Thromboembolism is a major complication in patients with ventricular assist devices (VAD). Anticoagulation with heparin, coumarin, and anti-platelet agents, particularly the development of biocompatible surfaces such as inner pseudo-endothelial layers or a coating with heparin, are intended to reduce these complications. However, the administration of heparin can lead to heparin induced thrombocytopenia type II (HIT II). Predominantly heparin/platelet factor 4 (HPF4) antibodies are responsible for the development of HIT II. The goal of the present investigation was to assess the prevalence of these antibodies in patients with heparin coated and noncoated VADs. Fifty-five patients were enrolled in the investigation. A heparin coated system was implanted in 30 patients, and a noncoated system was implanted in 25 patients. Antibodies were evaluated before, on days 7 and 14, and 3 months after implantation. Testing was performed with the Heparin/Platelet factor 4 enzyme-linked immunosorbent assay (ELISA) (Stago, France). In 40 of the 55 patients, the formation of HPF4 antibodies was observed (73%). In 35 of these patients (88%), HPF4 antibodies were present before surgery. There were no differences between the groups. In 11 patients (equal from both groups), the antibodies disappeared after termination of systemic heparinization. We conclude that in a rather high percentage of patients with VADs HPF4 antibodies are found. This finding may be explained by the repetitive and prolonged exposure of these patients to heparin. Immobilized heparin, as presently used in the carmeda coating, seems not to influence the formation and persistence of HPF4 antibodies. Further studies will have to prove whether HPF4 antibodies contribute to thromboembolic complications in these patients.  相似文献   
88.
89.
Bleeding and thrombosis are long recognized complications of myelofibrosis (MF) and contribute significantly to its morbidity and mortality. However, so far, few studies have evaluated the frequency of these events, their characteristics, and their prognostic impact. Based on these studies, thrombotic events in MF are about as common as in essential thrombocytemia (ET) but less common than in polycythemia vera (PV), while bleeding events are relatively more common in MF than in ET or PV. The emergence of the concept of prefibrotic primary MF (PMF), which is associated with a higher frequency of thrombohemorrhagic complications than ET, and the growing evidence that prefibrotic PMF may also have a different thrombotic and bleeding risk profiles than fibrotic (overt) PMF have emphasized the need for a reappraisal of the risk of thrombosis and hemorrhage in patients with MF. In this review, we discuss the frequency of thrombosis and bleeding in patients with MF, including prefibrotic PMF and their established and potential risk factors.  相似文献   
90.
Mesenchymal hamartomas of the liver(MHLs) in adults are rare and potentially premalignant lesions, which present as solid/cystic neoplasms. We report a rare case of orthotopic liver transplantation in a patient with a giant MHL. In 2013, a 34-year-old female sought medical advice after a 2-year history of progressive abdominal distention and respiratory distress. Physical examination revealed an extensive mass in the abdomen. Computed tomography(CT) of her abdomen revealed multiple liver cysts, with the diameter of largest cyst being 16 cm × 14 cm. The liver hilar structures were not clearly displayed. The adjacent organs were compressed and displaced. Initial laboratory tests, including biochemical investigations and coagulation profile, were unremarkable. Tumor markers, including levels of AFP, CEA and CA19-9, were within the normal ranges. The patient underwent orthotopic liver transplantation in November 2013, the liver being procured from a 40-year-old man after cardiac death following traumatic brain injury. Warm ischemic time was 7.5 min and cold ischemic time was 3 h. The recipient underwent classical orthotopic liver transplantation. The recipient operative procedure took 8.5 h, the anhepatic phase lasting for 1 h without the use of venovenous bypass. The immunosuppressive regimen includedintraoperative induction with basiliximab and high-dose methylprednisolone, and postoperative maintenance with tacrolimus, mycophenolate mofetil, and prednisone. The recipient's diseased liver weighed 21 kg(dry weight) and measured 41 cm × 32 cm × 31 cm. Histopathological examination confirmed the diagnosis of an MHL. The patient did not experience any acute rejection episode or other complication. All the laboratory tests returned to normal within one month after surgery. Three months after transplantation, the immunosuppressive therapy was reduced to tacrolimus monotherapy, and the T-tube was removed after cholangiography showed no abnormalities. Twelve months after transplantation, the patient remains well and is fulfilling all normal activities. Adult giant MHL is extremely rare. Symptoms, physical signs, laboratory results, and radiographic imaging are nonspecific and inconclusive. Surgical excision of the lesion is imperative to make a definite diagnosis and as a cure. Liver transplantation should be considered as an option in the treatment of a non-resectable MHL.  相似文献   
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