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991.
An aneuploid-immune paradox encompasses somatic copy-number alterations (SCNAs), unleashing a cytotoxic response in experimental precancer systems, while conversely being associated with immune suppression and cytotoxic-cell depletion in human tumors, especially head and neck cancer (HNSC). We present evidence from patient samples and cell lines that alterations in chromosome dosage contribute to an immune hot-to-cold switch during human papillomavirus-negative (HPV) head and neck tumorigenesis. Overall SCNA (aneuploidy) level was associated with increased CD3+ and CD8+ T cell microenvironments in precancer (mostly CD3+, linked to trisomy and aneuploidy), but with T cell-deficient tumors. Early lesions with 9p21.3 loss were associated with depletion of cytotoxic T cell infiltration in TP53 mutant tumors; and with aneuploidy were associated with increased NK-cell infiltration. The strongest driver of cytotoxic T cell and Immune Score depletion in oral cancer was 9p-arm level loss, promoting profound decreases of pivotal IFN-γ-related chemokines (e.g., CXCL9) and pathway genes. Chromosome 9p21.3 deletion contributed mainly to cell-intrinsic senescence suppression, but deletion of the entire arm was necessary to diminish levels of cytokine, JAK-STAT, and Hallmark NF-κB pathways. Finally, 9p arm-level loss and JAK2-PD-L1 codeletion (at 9p24) were predictive markers of poor survival in recurrent HPV HNSC after anti–PD-1 therapy; likely amplified by independent aneuploidy-induced immune-cold microenvironments observed here. We hypothesize that 9p21.3 arm-loss expansion and epistatic interactions allow oral precancer cells to acquire properties to overcome a proimmunogenic aneuploid checkpoint, transform and invade. These findings enable distinct HNSC interception and precision-therapeutic approaches, concepts that may apply to other CN-driven neoplastic, immune or aneuploid diseases, and immunotherapies.

The genetic bases for predisposition, and neoplastic transformation, to cancer have been increasingly well described. However, it remains less clear how early, precancer cells employ these genetic alterations to acquire the characteristic features and properties (1) of malignant disease. For example, studies of the immune landscape led to breakthrough trials of programmed death-1 (PD-1) inhibitors for recurrent, metastatic head and neck squamous cell carcinoma (HNSC) therapy (24). This underscores the importance of immune modulation in these tumors, despite a still suboptimal overall response rate of less than 20% in advanced cancers. Immune response within tumors has been observed to be strongest at the earliest neoplastic stages, as reported recently in lung adenocarcinoma precursors (5). As such, new, immune-based strategies could be developed to reduce the high global burden of HNSC, by intercepting the most common precursor of the most common HNSC presentation: HPV oral squamous cell carcinomas (68).Studies of chromosome somatic copy-number (CN) alteration (SCNA) profiles have reported the impact of 3p14, 9p21, or 17p13 loss in molecular models of HNSC progression (9) and risk (1015). Early studies reported that patients with oral precancers harboring 9p21 and/or 3p14 loss were at significantly greater cancer risk than those with retention at these loci (10, 16). A comprehensive, prospective validation study examined the relative contribution of six candidate chromosome-arm regions. 9p21 loss had the greatest influence on cancer risk (13). The mechanism underlying the association between CN and malignant transformation of precancers, however, is unclear (1720). Studies of CN-altered neoplastic cells have shown that SCNAs can trigger a cytotoxic response in experimental precancer systems (21, 22) but, paradoxically, were associated with immune evasion (23) and suppression (24) in computational studies of naturally occurring human cancers. The latter, in melanoma, found that nonresponders to PD-1 and CTLA-4 blockade had higher CN alteration and loss burdens, which correlated with immunologically cold tumors, characterized by cytotoxic-cell, marker, and metric reductions, and suppressive microenvironment cell, network, and signal increases (2326). This SCNA-cold association was particularly strong in our previous, pan-The Cancer Genome Atlas (TCGA) computational study in HNSC (23). These data point to a putative in vivo switch from immune hot-to-cold in the precancer–cancer transition, and raise the hypothesis that SCNAs in precursor lesions contribute to malignant transformation through genomic events and mechanisms that enable the acquisition of immune-suppressive, evasive properties. To test this hypothesis, we evaluated CN influence on immune profiles and outcomes in a large prospective oral precancer patient cohort, and HPV HNSC (tissue specimens and cell lines) and anti–PD-1–treated recurrent-disease cohorts.  相似文献   
992.
We report the case of a 53‐year‐old woman with a gastrointestinal stromal tumor (GIST) of the duodenum that showed only extramural growth, mimicking a pancreatic tumor. Preoperatively, computed tomography (CT) and angiography revealed a hypervascular mass, 3.0 cm in diameter, in the pancreatic head. Hypotonic duodenography showed compression of the second and third portions of the duodenum by the pancreatic lesion. Endoscopic examination showed no specific mucosal abnormalities in the duodenal lumen. The pancreatic head tumor was diagnosed preoperatively as a nonfunctioning islet cell tumor of the pancreas, and the patient underwent pylorus‐preserving pancreaticoduodenectomy. A hard mass was palpated intraoperatively in the pancreatic head region, and neither peritoneal dissemination nor metastasis was detected. Histologically, the tumor was composed of spindle‐shaped cells with a fascicular growth pattern, and only a few mitotic features were seen. Immunohistochemically, most of the tumor cells were positive for c‐kit oncoprotein and CD34, but negative for alpha‐smooth muscle actin and S‐100 protein. Therefore, this neoplasm was finally diagnosed as a duodenal GIST of the uncommitted type. This is a rare case of a duodenal GIST with exclusively extramural growth mimicking a pancreatic head tumor.  相似文献   
993.
994.
Aim: In Caucasians in northern Europe and North America, type 1 autoimmune hepatitis is characterized by susceptibility to human leukocyte antigens DR3 and DR4, and patients with zone III necrosis more frequently have an acute onset of the disease and a lower frequency of cirrhosis than those without. In Japanese patients, however, type 1 autoimmune hepatitis is primarily associated with DR4, and there are almost no DR3-positive patients. Thus, the clinical features of Japanese patients with type 1 autoimmune hepatitis and zone III necrosis may be different from those reported previously for Caucasians. Methods: We investigated 160 consecutive patients with type 1 autoimmune hepatitis (20 males and 140 females; median age, 55 years; range, 16-79 years). Results: Forty-seven patients (29%) had zone III necrosis, and these patients had lower serum levels of albumin and higher serum levels of total bilirubin, aspartate aminotransferaseand alanine aminotransferase. Histologically, zone III necrosis was found more frequently in patients with acute hepatitis than in those with chronic hepatitis. However, there was no difference in the frequency of cirrhosis between patients with and without zone III necrosis. In addition, normalization of serum alanine aminotransferase levels within six months after the introduction of corticosteroid treatment was slightly more frequent in patients with zone III necrosis (95% vs. 88%). Conclusion: In Japanese patients, zone III necrosis may reflect not only acute autoimmune hepatitis, but also acute exacerbation of pre-existing chronic disease. Furthermore, patients with zone III necrosis may respond better to corticosteroid treatment than those without.  相似文献   
995.
Abstract: Aims/Background: One function of Kupffer cells is the phagocytosis of nonviable hepatocytes. Our aims were to develop a model for phagocytosis of damaged hepatocytes by rat Kupffer cells in vitro, and to characterise prostaglandin E2 (PGE2), prostacyclin (PGI), and tumour necrosis factor-α (TNF) production in this model. Methods: Kupffer cells were incubated alone or with damaged hepatocytes for up to 18 h, then washed and cultured for up to 66 h. To compare mediator responses produced during inert particle phagocytosis, Kupffer cells were also incubated with latex beads. Results: Phagocytic uptake of hepatocyte debris was confirmed in at least 50% of Kupffer cells. A dissociation between TNF and PGI responses was found for both latex beads and damaged hepatocytes, such that a TNF secretory response was not triggered by either stimulus whereas PGI production was increased for both. Although phagocytosis of beads increased PGE2 production, phagocytosis of hepatocytes did not. Conclusions: Phagocytosis of damaged hepatocytes by Kupffer cells results in the production of PGI but not PGE2 or TNF.  相似文献   
996.
Summary. Serum concentrations of tumour necrosis factor alpha (TNF-α), interleukin-1 receptor antagonist (IL-1ra), interferon gamma (IFN-γ), interleukin-6 (IL-6) and interleukin-10 (IL-10) were studied in 31 patients with haematological malignancies during febrile neutropenia. Samples were obtained when blood cultures were performed (time 0) and, when possible, after 2, 4, 6, 12 and 24 h. Increased levels of all cytokines were detected after start of fever with peak values in gram-negative (Gr) bacteraemias after 2 h (TNF-α, IL-lra and IFN-γ), 4h (IL-6) and 6 h (IL-10), respectively. At time 0 the median TNF-α value was higher in the Gr group (80 pg/ml; range 54-516 pg/ml) as compared to both gram-positive bacteraemias (Gr+, 14pg/ ml; range 7-60 pg/ml; P < 0 05) and blood culture negative episodes (BCN, 8pg/ml; range 0-87pg/ml; P<0 05).
Furthermore, the peak values of TNF-α, IL-lra, IL-6 and IL-10 during the 24 h study period were significantly and/or numerically higher in the Gr- group in comparison to the Gr+ and BCN groups, respectively. It may be concluded that neutropenic patients have increased levels of both pro- and anti-inflammatory cytokines at start of fever, with the highest values recorded during the first hours in Gr- bacteraemias. Prospective studies will show whether monitoring of serum cytokines may be used as an early diagnostic tool before results of blood cultures are available, which may have important therapeutic implications.  相似文献   
997.
Objective: Records of metric data of birth, serve not only the medical needs of the newborn baby, but are also indicators to assess the status of public health.

Methods: This is a retrospective study of 4946 newborns (singleton: 2508 boys and 2365 girls) born in 1989 and in 2009 at the Department of Obstetrics and Gynaecology of the University of Szeged. We aimed as to compare and map the metrical changes over 20 years, and to describe the averages of four body parameters of the normal birth weight (2500–4000?g) subgroup (3993 singleton babies) in both years. Statistical analysis was performed with SPSS 17.0.

Results: In 1989, the mean birth weight was 3223.770?±?559.595?g, birth length 49.551?±?2.729?cm, chest circumference 32.181?±?2.231?cm, and head circumference 34.122?±?1.688?cm. In 2009, the birth weight was 3309.673?±?582.630?g, birth length 49.515?±?2.658?cm, chest circumference 32.736?±?2.392?cm and head circumference 33.854?±?1.768?cm. The mean birth weight, chest circumference and the maximum value of birth weight have thus increased. The mean maternal age shifted to 30.21?±?4.863 years, which is an increase of 3.57 years in 20 years.

Conclusion: The body parameters of newborns changed significantly between 1989 and 2009. As underlying causes changes in eating habits and lifestyle of the mother are to be mentioned.  相似文献   
998.

Background

As one of the most common work-related musculoskeletal disorders and postural deviations, forward head posture (FHP), is considered to lead to muscle imbalance.

Objectives

The aim of this study is to investigate the bilateral cross-sectional area (CSA) of the deep neck flexor muscles at rest and during five stages of the craniocervical flexion (CCF) test in individuals with FHP and the controls with normal head posture.

Methods

Eighteen students with FHP and 18 controls with normal head posture, all females aged 18–35 years, participated in this study. Participants were categorized into two groups based on their craniovertebral angle. The CSA of the deep neck flexors was measured using ultrasonography while participants lay supine on the table with a pressure biofeedback unit placed under their necks in order to let the examiner measure the CSA of the muscles during rest and five stages of the CCF test including 22, 24, 26, 28, and 30 mmHg of the pressure biofeedback unit.

Results

A significant effect of contraction level was observed in both groups, indicating significant increases of the CSA of the deep neck flexors during contraction (F = 64.37, P < 0.001). No significant difference was evident for the CSA of the deep neck flexors between the groups, although the increase in the CSA of the deep neck flexors was up to 28 mmHg in the normal head posture group compared to 26 mmHg in the FHP group.

Conclusions

The results of the present study showed no significant difference between the performance of the deep neck flexors during the CCF test in FHP and normal head posture individuals, which challenge the common belief of the deep neck flexors weakness in individuals sustaining FHP.  相似文献   
999.
Background: Biosimilars are approved biologics that match reference medicine in quality, safety, and efficacy. The development of Sandoz proposed biosimilar adalimumab (SPBA; GP2017) involved a target-directed, iterative state-of-the-art quality-by-design development program. Here, we describe the functional and pharmacological characterization of SPBA and its proposed mechanism of action in immune-mediated inflammatory diseases.

Methods: Sensitive in vitro binding and functional characterization studies, and nonclinical evaluations (pharmacokinetics, pharmacodynamics, and safety/toxicology) were performed as part of a stepwise approach to confirm the biosimilarity of SPBA with reference adalimumab.

Results: Matching values were reported for SPBA and reference adalimumab in binding assays involving tumor necrosis factor (TNF)-α, complement 1q and human immune effector cell Fcγ receptor subtypes in cell-based bioassays for Fc receptor function (complement- and antibody-dependent cytotoxicity), and in apoptosis inhibition. Furthermore, SPBA and reference adalimumab were equivalent in terms of membrane TNF binding and induction of reverse signaling. Pharmacokinetics of SPBA and reference adalimumab were comparable in rabbits, and the two biologics were equally effective in a human TNF transgenic mouse model of polyarthritis.

Conclusion: SPBA matches reference adalimumab with regards to target binding, functional, pharmacokinetic, and pharmacodynamic properties at the nonclinical level supporting its approval in all indications of the reference adalimumab.  相似文献   

1000.
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