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91.
A case of acinar-islet cell carcinoma presenting as insulinoma is reported. The patient was a 28-year-old man who presented with two convulsive episodes. Fajans' index [immunoreactive insulin (IRI; μU/ml/ glucose mg/dl)] and Turner's [IRI (μU/ml) × 100/glucose (mg/dl)—30] index were high (2.8 and 308, respectively), as were serum proinsulin levels (550pg/ml). Abdominal computed tomography and angiography revealed a highly vascular tumor in the pancreatic tail and several similar tumors in the liver. Histologic features of a biopsy specimen from a hepatic tumor were those of a malignant pancreatic endocrine tumor. Insulin secretion by the liver metastases was confirmed by venous sampling after arterial stimulation with calcium. These findings led us to diagnose malignant insulinoma with liver metastases. Serum levels of α-fetoprotein and trypsin were markedly elevated, to 2234ng/ml (normal <10) and 22000ng/ml (normal<460) respectively, and these levels continued to rise with further growth of the liver metastases. Immunohistochemically, the metastatic liver tumor specimen was positive for α-fetoprotein, α1-antichymotrypsin, chromogranin A, and neuron-specific enolase. These findings of amphicrine features in the tumor were indicative of acinar-islet cell carcinoma that produced α-fetoprotein and trypsin in addition to insulin.  相似文献   
92.

Background

We aimed to clarify the prognosis and pathophysiological parameters of low T3 syndrome in patients with heart failure (HF).

Methods and Results

Hospitalized patients with HF and euthyroidism (n?=?911) were divided into 2 groups on the basis of free triiodothyronine (FT3) serum levels: the normal FT3 group (FT3 ≥2.3 pg/mL; n?=?590; 64.8%) and the low FT3 group (FT3 <2.3 pg/mL; n?=?321; 35.2%). We compared post-discharge cardiac and all-cause mortality by means of Kaplan-Meier analysis and Cox proportional hazard analysis, and the parameters of echocardiography and cardiopulmonary exercise testing by means of Student t test. In the follow-up period of median 991 (interquartile range 534-1659) days, there were 193 all-cause deaths, including 88 cardiac deaths. Cardiac and all-cause mortality were higher in the low FT3 group (log-rank P < .01). Low FT3 was a predictor of cardiac death (hazard ratio 1.926, 95% confidence interval [CI] 1.268–2.927; P?=?.002) and all-cause death (hazard ratio 2.304, 95% CI 1.736–3.058; P < .001). Although left ventricular ejection fraction was similar between the groups, the low FT3 group showed lower peak VO2 (13.6 ± 4.6 vs 16.6 ± 4.4 mL·kg?1·min,?one P < .001) and higher VE/VCO2 slope (36.5 ± 8.2 vs 33.0 ± 7.5; P?=?.001).

Conclusion

Low T3 syndrome in patients with HF is associated with higher cardiac and all cause-mortality.  相似文献   
93.

Background/Objectives

A breakthrough in chemotherapy for pancreatic ductal adenocarcinoma (PDAC) may be achieved using precision medicine, which involves identifying cases that are highly likely to respond to a certain treatment and then performing that treatment. BRCAness has been receiving attention as a novel predictor of anticancer drug sensitivity in PDAC, making the screening of BRCAness paramount.

Methods

We conducted the first-ever examination of the feasibility of analyzing BRCAness using multiplex ligation-dependent probe amplification (MLPA). Formalin-fixed paraffin-embedded (FFPE) tissue samples obtained via endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) from 20 patients with the highest pancreatic carcinoma cell counts in tissue samples out of 40 consecutive PDAC patients who underwent EUS-FNAB at our hospital were analyzed by MLPA for BRCAness.

Results

We were able to accurately analyze BRCAness in 75% of the 20 cases of PDAC using FFPE tissue obtained by EUS-FNAB. BRCAness was observed in one of the 20 cases.

Conclusions

In PDAC, analyzing BRCAness by MLPA using FFPE tissue obtained by EUS-FNAB offers the remarkable benefit of yielding results in a short period of time and at a low cost. In addition, this method of BRCAness analysis may prove to be a feasible and effective approach for performing precision medicine.  相似文献   
94.

Background

It is widely recognized that overt hyper- as well as hypothyroidism are potential causes of heart failure (HF). Additionally it has been recently reported that subclinical hypothyroidism (sub-hypo) is associated with atherosclerosis, development of HF, and cardiovascular death. We aimed to clarify the effect of sub-hypo on prognosis of HF, and underlying hemodynamics and exercise capacity.

Methods

We measured the serum levels of thyroid stimulating hormone (TSH) and free thyroxine (FT4) in 1100 consecutive HF patients. We divided these patients into 5 groups on the basis of plasma levels of TSH and FT4, and focused on euthyroidism (0.4 ≤ TSH ≤ 4 μIU/mL and 0.7 ≤ FT4 ≤ 1.9 ng/dL; n = 911; 82.8%) and sub-hypo groups (TSH > 4 μIU/mL and 0.7 ≤ FT4 ≤ 1.9 ng/dL; n = 132; 12.0%). We compared parameters of echocardiography, cardiopulmonary exercise testing, and cardiac catheterization, and followed up for cardiac event rate and all-cause mortality between the 2 groups.

Results

Although left ventricular ejection fraction did not differ between the 2 groups, the sub-hypo group had lower peak breath-by-breath oxygen consumption and higher mean pulmonary arterial pressure than the euthyroidism group (peak breath-by-breath oxygen consumption, 14.0 vs 15.9 mL/min/kg; P = 0.012; mean pulmonary arterial pressure, 26.8 vs 23.5 mm Hg, P = 0.020). In Kaplan-Meier analysis (mean 1098 days), the cardiac event rate and all-cause mortality were significantly higher in the sub-hypo group than those in the euthyroidism group (log rank, P < 0.01, respectively). In Cox proportional hazard analysis, sub-hypo was a predictor of cardiac event rate and all-cause mortality in HF patients (P < 0.05, respectively).

Conclusions

Sub-hypo might be associated with adverse prognosis, accompanied by impaired exercise capacity and higher pulmonary arterial pressure, in HF patients.  相似文献   
95.
Sit-to-stand exercise (STS) is a common activity of daily living. The objectives of the present study were: 1) to assess the validity of aerobic fitness measurements based on anaerobic thresholds (ATs), during incremental sit-to-stand exercise (ISTS) with and without arm support compared with an incremental cycle-ergometer (CE) test; and 2) to examine the reproducibility of the AT measured during the ISTSs. Twenty-six healthy individuals randomly performed the ISTS and CE test. Oxygen uptakes at the AT (AT-VO2) and heart rate at the AT (AT-HR) were determined during the ISTSs and CE test, and repeated-measures analyses of variance and Tukey’s post-hoc test were used to evaluate the differences between these variables. Pearson correlation coefficients were used to assess the strength of the relationship between AT-VO2 and AT-HR during the ISTSs and CE test. Data analysis yielded the following correlations: AT-VO2 during the ISTS with arm support and the CE test, r = 0.77 (p < 0.05); AT-VO2 during the ISTS without arm support and the CE test, r = 0.70 (p < 0.05); AT-HR during the ISTS with arm support and the CE test, r = 0.80 (p < 0.05); and AT-HR during the ISTS without arm support and the CE test, r = 0.66 (p < 0.05). The AT-VO2 values during the ISTS with arm support (18.5 ± 1.9 mL·min-1·kg-1) and the CE test (18.4 ± 1.8 mL·min-1·kg-1) were significantly higher than those during the ISTS without arm support (16.6 ± 1.8 mL·min-1·kg-1; p < 0.05). The AT-HR values during the ISTS with arm support (126 ± 10 bpm) and the CE test (126 ± 13 bpm) were significantly higher than those during the ISTS without arm support (119 ± 9 bpm; p < 0.05). The ISTS with arm support may provide a cardiopulmonary function load equivalent to the CE test; therefore, it is a potentially valid test for evaluating AT-VO2 and AT-HR in healthy, young adults.

Key points

  • The ISTS is a simple test that varies only according to the frequency of standing up, and requires only a small space and a chair.
  • The ISTS with arm support is valid and reproducible, and is a safe test for evaluating AT in healthy young adults.
  • For evaluating the AT, the ISTS may serve as a valid alternative to conventional CPX, using either a cycle ergometer or treadmill, in cases where the latter methods are difficult to implement.
Key words: Sit-to-stand, cycle ergometer, anaerobic threshold, correlations, reproducibility, validity  相似文献   
96.
A 72-year-old woman was admitted with left cervical lymphadenopathy, high fever, pancytopenia and liver dysfunction. Bone marrow aspiration showed infiltration of large atypical lymphoid cells and hemophagocytic histiocytes, thus suggesting a diagnosis of lymphoma associated hemophagocytic syndrome (LAHS). An abdominal CT scan revealed multiple low-density areas in the liver, and the patient's liver function rapidly deteriorated. Histologically, the cervical biopsy showed lymphoma cell infiltration with prominent necrosis and karyorrhectic debris. The lymphoma cells expressed CD3+, CD4-, CD8+, CD20-, CD56+/-, TIA-1+, granzyme B+, and EBER was positive using in situ hybridization. DNA analysis of the TCR beta and gamma chain gene with the Southern blot showed rearranged bands. These findings were compatible with those of EB-virus associated peripheral T-cell lymphoma. After chemotherapy with the THP-COP regimen, the patient's liver dysfunction improved rapidly, but she died from bacterial peritonitis due to perforation of a recurrent duodenal ulcer. Post-mortem examination of the liver showed multiple irregular massive necroses of the hepatocytes, where no lymphoma cell infiltration was present. Hemophagocytic histiocytosis was remarkable in the bone marrow, spleen, lymph nodes, and liver. Marked elevation of serum levels of cytokines such as TNF-alpha or IFN-gamma suggests that these cytokines played an important role in the pathogenesis of the hepatic cell necrosis.  相似文献   
97.
Genetic analysis was carried out in human fibroblasts (KMST-6) immortalized by treatment with60Co gamma rays in order to determine if any genetic change was involved in the immortal transformation of human cells. Analysis by restriction fragment length polymorphism revealed an alteration in chromosome 13q12–14, in which the retinoblastoma (RB) gene locus (13q14) is located. Then the RB gene itself was examined. Structural abnormalities in the RB gene were detected by Southern blot analysis. Furthermore, abnormal RB protein (pRB) was expressed in immortalized KMST-6 cells, as shown by in vitro phosphorylation, whereas normal KMS-6 cells expressed the intact pRB. These findings indicated that inactivation of the RB gene is one of the key events of the immortalization of human cells.Abbreviations RB retinoblastoma - pRB retinoblastoma gene product (protein) - T simian virus 40 large T antigen - E1A adenovirus E1A protein  相似文献   
98.
Objectives: The success rate of dental implants depends on the type of bone at the implant site. The purpose of the present study was to investigate the effects of the bone parameters at the implant-placement site on peri-implant bone strain distributions. Study Design: The morphologies and bone densities of seventy-five potential implant sites in the posterior mandible were measured using computed tomography (CT). Based on the CT data, we defined bone parameters (low and high in terms of cancellous-bone density and crestal-cortical bone density, and thin and thick in terms of crestal-cortical bone thickness), and we constructed finite-element models simulating the various bone types. A buccolingual oblique load of 200 N was applied to the top of the abutment. The von Mises equivalent (EQV) strains in the crestal-cortical bone and in the cancellous bone around the implant were calculated. Results: Cancellous-bone density greatly affected the maximum EQV strain regardless of the density and thickness of the crestal cortical-bone. The maximum EQV strains in the crestal cortical-bone and the cancellous bone in the low-density cancellous-bone models (of 150 Hounsfield units (HU) were 1.56 to 2.62-fold and 3.49 to 5.31-fold higher than those in the high-density cancellous-bone models (of 850 HU), respectively. The crestal cortical-bone density affected the maximum EQV strains in the crestal cortical-bone and in the cancellous bone in the low-density cancellous-bone models. The crestal cortical-bone thickness affected the maximum EQV strains in the cancellous bone and in the crestal cortical-bone in the low-density cancellous-bone models. Conclusions: Our results confirm the importance of bone types for the peri-implant bone strain distribution. Cancellous-bone density may be a critical factor for peri-implant bone strain. Key words:Dental implant, bone density, finite-element analysis.  相似文献   
99.
100.
Duodenal gastric heterotopia (DGH) is a benign asymptomatic condition assumed to be of congenital origin. Since DGH is often associated with fundic gland polyps (FGPs) that frequently carry a somatic β-catenin gene mutation, we examined whether DGH, either sporadic or FGP-associated, is attributable to alterations of the Wnt/β-catenin pathway. Genetic analysis revealed frequent somatic β-catenin gene mutations in DGH; some of which showed the same mutation pattern as coexisting FGPs. All missense mutations were confined to codons 32, 33, and 37. No such mutations were observed, however, in any of the specimens from focal gastric foveolar metaplasia (GFM). Therefore, DGH is not a mere congenital lesion due to aberrant migration of normal gastric mucosa or a simple reactive metaplasia after regenerative stimuli of the duodenal mucosa, but a distinct condition based upon molecular genetic changes in the Wnt/β-catenin pathway.  相似文献   
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