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941.
Preoperative elevations in the levels of serum amyloid A (SAA) or C‐reactive protein (CRP) have been reported to be prognostic indicators in several malignancies. The aim of this study is to evaluate the serum levels of SAA and CRP in the prognosis of esophageal squamous cell carcinoma (ESCC). In total, 252 patients with ESCC who had undergone surgery with curative‐intent were retrospectively recruited. The specificity, sensitivity, and prognostic value of SAA or CRP levels were measured as the area under the receiver operating characteristic (ROC) curve (AUC). The clinical value of SAA and CRP levels as prognostic indicators was evaluated using Cox's proportional hazards model. The 1‐, 3‐, and 5‐year overall survival (OS) rates for the entire cohort of patients with ESCC were 71.0%, 61.0%, and 43.0%, respectively. The correlation between the levels of SAA and CRP was significant (r2 = 0. 685, P < 0.001). The ROC analysis showed that the levels of CRP were associated with a significantly lower overall accuracy than were the SAA levels (AUC, 0.615 vs. 0.880; P < 0.001). For the complete cohort, the median OS was 52.0 months longer in patients with low preoperative serum levels of SAA (72.0 months) compared with patients who had high SAA levels (20.0 months, P < 0.001). The median OS among patients with low CRP levels was also longer compared with the patients who had high CRP levels (72.0 vs. 51.0 months, respectively; P < 0.001). Subgroup analyses showed that the preoperative elevated levels of SAA could find significant differences in OS for stage I, stage II, and stage III (P < 0.001, P = 0.001, and P < 0.001, respectively), whereas the increased levels of CRP could only find a difference in OS for stage II cancers. After a multivariate analysis, preoperative elevated level of SAA was found to be an independently and significant prognostic factor (P < 0.001). Our study indicates that the preoperative levels of SAA and CRP can act as prognostic factors, and that elevated levels of these proteins are associated with negative effects on the survival of patients with ESCC. SAA showed a higher prognostic value than CRP in both cohort and subgroup analysis.  相似文献   
942.
A very rare syndrome of rapid-onset obesity with hypoventilation, hypothalamic dysfunction and autonomic dysregulation (ROHHAD) has been recently described as causing morbidity due to hypothalamic dysfunction and respiratory arrest. Its prognosis is poor and often cardiac arrest occurs due to alveolar hypoventilation. This disorder can mimic genetic obesity syndromes and several endocrine disorders. We present a 13-year-old female patient who was reported to be healthy until the age of 3 years. She was admitted to our emergency department, presenting with respiratory distress. Features matching ROHHAD syndrome such as rapid-onset obesity, alveolar hypoventilation, central hypothyroidism, hyperprolactinemia, Raynaud phenomenon and hypothalamic hypernatremia were detected in the patient. In addition to these features, the patient was found to have hypergonadotropic hypogonadism and megaloblastic anemia. Because of its high mortality and morbidity, the possibility of ROHHAD syndrome needs to be considered in all pediatric cases of early- and rapid-onset obesity associated with hypothalamic-pituitary endocrine dysfunction.  相似文献   
943.
BK virus (BKV), a ubiquitous human polyomavirus, usually does not cause disease in healthy individuals. BKV reactivation and disease can occur in immunosuppressed individuals, such as those who have undergone renal transplantation or hematopoietic cell transplantation (HCT). Clinical manifestations of BKV disease include graft dysfunction and failure in renal transplant recipients; HCT recipients frequently experience hematuria, cystitis, hemorrhagic cystitis (HC), and renal dysfunction. Studies of HCT patients have identified several risk factors for the development of BKV disease including myeloablative conditioning, acute graft‐versus‐host disease, and undergoing an umbilical cord blood (uCB) HCT. Although these risk factors indicate that alterations in the immune system are necessary for BKV pathogenesis in HCT patients, few studies have examined the interactions between host immune responses and viral reactivation in BKV disease. Specifically, having BKV immunoglobulin‐G before HCT does not protect against BKV infection and disease after HCT. A limited number of studies have demonstrated BKV‐specific cytotoxic T cells in healthy adults as well as in post‐HCT patients who had experienced HC. New areas of research are required for a better understanding of this emerging infectious disease post HCT, including prospective studies examining BK viruria, viremia, and their relationship with clinical disease, a detailed analysis of urothelial histopathology, and laboratory evaluation of systemic and local cellular and humoral immune responses to BKV in patients receiving HCT from different sources, including uCB and haploidentical donors.  相似文献   
944.
945.
946.
BACKGROUND Zinc is an essential trace element integral to many cellular and immune functions. Zinc deficiency is highly prevalent in patients with cirrhosis and related to disease severity.AIM To evaluate whether zinc supplementation improves clinical outcomes(disease severity and mortality) in patients with cirrhosis.METHODS This prospectively registered systematic review(PROSPERO reference: CRD42018118219) included all studies in Medline, Embase or Cochrane database with inclusion criteria of adult human studies, comparing zinc supplementation of at least 28 d with standard care or placebo in patients with cirrhosis. Mortality and clinical severity score data were extracted. Random effects meta-analyses compared mortality at 6 mo and 2 years. Risk of bias was assessed using the National Institutes of Health quality assessment tool.RESULTS Seven hundred and twelve articles were identified of which four were eligible. Zinc formulations and doses varied(elemental zinc 3.4-214 mg daily) for different intervention periods in patients with differing etiology and severity of cirrhosis. Two studies were considered to be at high risk of bias. There was no significant difference in 6-mo mortality between patients treated with zinc versus controls [risk ratio 0.98(0.90-1.05)]. Changes in severity scores were not reported in any study.CONCLUSION Zinc supplementation is not associated with reduced mortality in patients with cirrhosis. Findings are limited by the small number of eligible studies and significant heterogeneity in intervention and patient population.  相似文献   
947.
Alcohol consumption is one of the leading causes of the global burden of disease and results in high healthcare and economic costs. Heavy alcohol misuse leads to alcohol-related liver disease, which is responsible for a significant proportion of alcohol-attributable deaths globally. Other than reducing alcohol consumption, there are currently no effective treatments for alcohol-related liver disease. Oxidative stress refers to an imbalance in the production and elimination of reactive oxygen species and antioxidants. It plays important roles in several aspects of alcohol-related liver disease pathogenesis. Here, we review how chronic alcohol use results in oxidative stress through increased metabolism via the cytochrome P4502E1 system producing reactive oxygen species, acetaldehyde and protein and DNA adducts. These trigger inflammatory signaling pathways within the liver leading to expression of pro-inflammatory mediators causing hepatocyte apoptosis and necrosis. Reactive oxygen species exposure also results in mitochondrial stress within hepatocytes causing structural and functional dysregulation of mitochondria and upregulating apoptotic signaling. There is also evidence that oxidative stress as well as the direct effect of alcohol influences epigenetic regulation. Increased global histone methylation and acetylation and specific histone acetylation inhibits antioxidant responses and promotes expression of key pro-inflammatory genes. This review highlights aspects of the role of oxidative stress in disease pathogenesis that warrant further study including mitochondrial stress and epigenetic regulation. Improved understanding of these processes may identify novel targets for therapy.  相似文献   
948.
BackgroundTranscervical esophagectomy is a less invasive procedure performed within mediastinum. However, the mediastinum offers limited surgical space and the surgery via this route differs from conventional minimally invasive esophagectomy. Therefore, the physiological study of this surgical approach on an animal model would be necessary before the procedure gained more popularity.MethodsWe conducted transcervical minimally invasive esophagectomy on animal model (swine) under CO2 pneumomediastinum. The hemodynamic parameters were monitored using float catheter cannulated via right jugular vein. At different anatomical level (the upper, middle, and lower thoracic part of the animal esophagus), increased artificial pneumomediastinal pressures (0, 4, 8, 12, and 16 mmHg) were consecutively allocated to record the intra-operative changes of blood pressure, cardiac output (CO), central venous pressure (CVP), pulmonary artery pressure (PAP) and extravascular lung water (EVLW). Meanwhile, the surgical field under different pneumomediastinum pressure was recorded and balanced with animals’ hemodynamic changes to determine the optimal pressure for transcervical minimally invasive esophagectomy.ResultsThe animal procedures were accomplished without conversions. During the upper thoracic stage, increased CO2 pressures did not lead to significant changes in hemodynamic parameters including the blood pressure, CO, CVP, PAP or the level of EVLW. During the middle thoracic stage, pneumomediastinum under 4–12 mmHg did not lead to significant changes in hemodynamic parameters. However, pneumomediastinum at 16 mmHg resulted in lower CO (P=0.038) when compared to 0–12 mmHg. During lower thoracic stage, as the pneumomediastinum pressures increased from 0 to 16 mmHg, significant decrease in CO (P=0.022), and increase in CVP (P=0.036) was recorded. In compared to 4 mmHg pneumomediastinum, the surgical field under 8–16 mmHg artificial CO2 pneumomediastinum was suitable for mediastinal manipulation.ConclusionsDuring transcervical minimally invasive esophagectomy on animal model, the mobilization of swine thoracic esophagus with optimal pneumomediastinum pressure 8–12 mmHg is safe and effective based on hemodynamic analysis.  相似文献   
949.
Identifying signaling pathways that regulate hematopoietic stem and progenitor cell (HSPC) formation in the embryo will guide efforts to produce and expand HSPCs ex vivo. Here we show that sterile tonic inflammatory signaling regulates embryonic HSPC formation. Expression profiling of progenitors with lymphoid potential and hematopoietic stem cells (HSCs) from aorta/gonad/mesonephros (AGM) regions of midgestation mouse embryos revealed a robust innate immune/inflammatory signature. Mouse embryos lacking interferon γ (IFN-γ) or IFN-α signaling and zebrafish morphants lacking IFN-γ and IFN-ϕ activity had significantly fewer AGM HSPCs. Conversely, knockdown of IFN regulatory factor 2 (IRF2), a negative regulator of IFN signaling, increased expression of IFN target genes and HSPC production in zebrafish. Chromatin immunoprecipitation (ChIP) combined with sequencing (ChIP-seq) and expression analyses demonstrated that IRF2-occupied genes identified in human fetal liver CD34+ HSPCs are actively transcribed in human and mouse HSPCs. Furthermore, we demonstrate that the primitive myeloid population contributes to the local inflammatory response to impact the scale of HSPC production in the AGM region. Thus, sterile inflammatory signaling is an evolutionarily conserved pathway regulating the production of HSPCs during embryonic development.  相似文献   
950.

Purpose

The objective of this study was to provide the morphological details on small branches of the portal vein in transverse groove of hepatic hilum.

Methods

According to the surgery significance, the small branches of portal vein in transverse groove of hepatic hilum were named as “Short hepatic portal veins (SHPVs)”. SHPVs were minutely dissected in 30 adult cadaveric livers. The number, diameter, length, origin points, and entering liver sites of SHPVs were explored and measured.

Results

There were 181 SHPVs in 30 liver specimens, including 46 % (83/181) from the left portal vein, 31 % (56/181) from the bifurcation, and 23 % (42/181) from the right portal vein. At the entering liver sites of SHPVs, 22 % (40/181) supplied for segment IV, 9 % (17/181) for segment V, 4 % (7/181) for segment VI, 23 % (41/181) for segment VII, and 42 % (76/181) for segment I (caudate lobe). There were 6.0 ± 2.4 branches per liver specimen with range 3–12. The mean diameter of SHPVs was 2.25 ± 0.89 mm. The average length of SHPVs was 4.86 ± 2.12 mm.

Conclusions

SHPVs widely existed in each liver specimen. The detailed anatomical study of SHPVs could be useful to avoid damaging the short portal branches during hepatic operations, such as isolated or combined caudate lobectomy.  相似文献   
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