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101.
Özdemir  Selçuk  Şengez  Burcu  Arslanoğlu  Alper 《Virus genes》2020,56(2):182-193

African monkeys are resistant to HIV-1 infection due to intrinsic restriction mechanisms found in their cells. However, although they can be infected by monkey-adapted modified HIV-1 particles that are designed to overcome known restriction factors, virus numbers drop to undetectable levels in immunocompetent animals. These results indicate the possibility of the presence of yet unidentified factor(s) that restrict HIV-1 in old-world monkey (OWM) cells after integration of the viral genome into the host cell chromosome. In the light of these findings, we hypothesized that OWMs might have evolved resistance mechanism(s) against HIV-1 by switching specific gene(s) on in response to the synthesis of viral proteins in infected cells. In an attempt to mimic post-infection status, we expressed HIV-1 Tat gene in African green monkey cells and compared the whole proteome with normal cells and identified secretory leukocyte protease inhibitor (SLPI), a protein with known extracellular anti-HIV-1 activity, as an over-expressed protein in the presence of HIV-1 Tat protein by 2D-PAGE and mass spectrometry analysis. We also showed that overexpression of SLPI in the presence of HIV-1 Tat was specific to monkey cells. Our results also suggest that SLPI had a previously undiscovered intracellular anti-HIV activity in addition to its extracellular activity.

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102.
The skin of the South American fur seal (Arctocephalus australis) is important for animal thermoregulation in both terrestrial and aquatic environments. Skin tissue samples were collected from A. australis for microscopic analysis and were related to anatomical references. The aim of this study was to describe the skin morphology, as well as to suggest the major anatomical regions and skin components involved in the thermoregulation of this species. Using light microscopy, the skin of six animals was examined based on histological, morphometric, and immunohistochemical criteria. Hair follicle morphology was examined using scanning electron microscopy. The skin was classified as either thick or thin based on its epidermal thickness. The thin epidermis regions had more abundant hair follicles, as well as high pigmentation, whereas the thick epidermis regions had very pigmented epidermal layers. Pigmentation of hair and skin is fundamental for protection against ultraviolet rays; moreover, hair is important in preventing abrasion, and provides an insulating layer against the external environment, which can be much colder than body temperature. Furthermore, the dermis is well vascularized, especially the superficial dermis. All regions of the skin have adaptations for maintaining the animal's condition in both terrestrial and aquatic environments. Among the studied regions, the interdigital region from hindflipper showed important morphological characteristics related to thermoregulation, such as having an epidermis of intermediate thickness, a dermis with a small number of hairs, a large amount of blood vessels, and sweat glands with large lumens, indicating that heat exchange in this region may be faster.  相似文献   
103.
Congenital megalourethra is a rare urogenital malformation characterized by severe dilatation and elongation of the penile urethra. It causes functional obstruction of the lower urinary system. Herein, we present a newborn with congenital megalourethra with single umbilical artery.  相似文献   
104.
Systemic AA amyloidosis is a serious complication of many chronic inflammatory disorders and chronic infections. Renal involvement is seen in the majority of the patients and can lead to end‐stage renal disease. Renal transplantation can be performed in these patients; however, amyloidosis can recur in the transplanted kidneys. On the other hand, de novo AA amyloidosis in renal transplant patients has been rarely reported. We report a 17‐yr‐old patient with end‐stage renal disease due to genitourinary anomalies who developed recurrent pyelonephritis after transplantation. Three yr after transplantation, renal biopsy was performed for proteinuria and AA amyloidosis was identified in the renal allograft. Although rare, chronic infections might cause de novo amyloidosis in renal transplant patients. Therefore, amyloidosis should be kept in mind in those types of patients who present with proteinuria.  相似文献   
105.
Background: YKL‐40, a new acute‐phase protein, is shown to be elevated in inflammatory diseases, such as rheumatoid arthritis, type 2 diabetes mellitus, and coronary artery diseases. However, there is no data indicating a relationship between YKL‐40 and periodontal disease. Interleukin‐6 (IL‐6) is the major regulator of acute‐phase protein synthesis and one of the most studied inflammatory markers in periodontal disease. The purpose of the present study is to evaluate YKL‐40 and IL‐6 levels in gingival crevicular fluid (GCF) and serum of patients with periodontal disease and healthy individuals. Methods: Periodontally healthy individuals (n = 15), patients with gingivitis (n = 15), and patients with severe chronic periodontitis (CP) (n = 15) without any systemic disease were included in the study. Clinical measurements were recorded; GCF and blood samples were obtained from each participant. GCF and serum YKL‐40 and IL‐6 levels were analyzed by enzyme‐linked immunosorbent assay. Statistical analysis was performed by parametric and non‐parametric tests. Results: Total amounts of YKL‐40 and IL‐6 in GCF as well as serum YKL‐40 and IL‐6 levels were significantly higher in patients with gingivitis and CP compared with healthy controls (P <0.01). YKL‐40 levels in GCF and serum as well as serum IL‐6 levels were significantly higher in patients with CP compared with patients with gingivitis (P <0.01). Conclusions: YKL‐40 levels in GCF as well as serum YKL‐40 and IL‐6 levels increased from gingivitis to periodontitis. Within the limits of the present study, the YKL‐40 molecule might be a potential novel inflammatory marker of periodontal disease.  相似文献   
106.
Background: Perianal disease is reported more widely in pediatric Crohn patients than in the past, and has been stated as an independent modifier of the disease behavior. In this study, we aimed to analyze the clinical characteristics and outcomes of fistulising perianal Crohn’s disease (fpCD) in the pediatric age group.Methods: A total number of 149 children with an established diagnosis of inflammatory bowel disease who have been diagnosed before 18 years of age and followed in our tertiary center were revised. Clinical, endoscopic, laboratory, and radiologic data of 50 patients with CD, who had at least 18 months follow-up data, were compiled.Results: Of 50 patients, 26 (52%) were diagnosed as fpCD (38% at onset). More than half of the patients without any notable external orifices around the perianal area were diagnosed as fpCD by an magnetic resonance imaging (MRI). Pediatric fpCD patients had a higher disease activity score and platelet count, lower serum albumin level, and a higher rate of granuloma in the biopsy samples, compared with non-fistulising patients. A considerably high rate of surgical interventions (i.e., seton placement 46% and abscess drainage 15%) was performed in combination with infliximab.Conclusion: Fistulising perianal Crohn’s disease seems to be more common than previously reported in the pediatric age group. A severe course of the disease might serve as a warning for the development of fpCD. A careful physical examination and use of perianal MRI with a high index of suspicion may increase the likelihood of fistula detection, hence may change the treatment strategy.  相似文献   
107.
Iris Cervenka  Marie Al Rahmoun  Yahya Mahamat-Saleh  Agnès Fournier  Marie-Christine Boutron-Ruault  Gianluca Severi  Saverio Caini  Domenico Palli  Reza Ghiasvand  Marit B. Veierod  Edoardo Botteri  Anne Tjønneland  Anja Olsen  Renée T. Fortner  Rudolf Kaaks  Matthias B. Schulze  Salvatore Panico  Antonia Trichopoulou  Clio Dessinioti  Katerina Niforou  Sabina Sieri  Rosario Tumino  Carlotta Sacerdote  Bas Bueno-de-Mesquita  Torkjel M. Sandanger  Sandra Colorado-Yohar  Maria J. Sánchez  Leire Gil Majuelo  Leila Lujan-Barroso  Eva Ardanaz  Susana Merino  Karolin Isaksson  Salma Butt  Ingrid Ljuslinder  Malin Jansson  Ruth C. Travis  Kay-Tee Khaw  Elisabete Weiderpass  Laure Dossus  Sabina Rinaldi  Marina Kvaskoff 《International journal of cancer. Journal international du cancer》2020,146(12):3267-3280
Evidence suggests an influence of sex hormones on cutaneous melanoma risk, but epidemiologic findings are conflicting. We examined the associations between use of oral contraceptives (OCs) and menopausal hormone therapy (MHT) and melanoma risk in women participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). EPIC is a prospective cohort study initiated in 1992 in 10 European countries. Information on exogenous hormone use at baseline was derived from country-specific self-administered questionnaires. We used Cox proportional hazards regression models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). Over 1992–2015, 1,696 melanoma cases were identified among 334,483 women, whereof 770 cases among 134,758 postmenopausal women. There was a positive, borderline-significant association between OC use and melanoma risk (HR = 1.12, 95% CI = 1.00–1.26), with no detected heterogeneity across countries (phomogeneity = 0.42). This risk increased linearly with duration of use (ptrend = 0.01). Among postmenopausal women, ever use of MHT was associated with a nonsignificant increase in melanoma risk overall (HR = 1.14, 95% CI = 0.97–1.43), which was heterogeneous across countries (phomogeneity = 0.05). Our findings do not support a strong and direct association between exogenous hormone use and melanoma risk. In order to better understand these relations, further research should be performed using prospectively collected data including detailed information on types of hormone, and on sun exposure, which may act as an important confounder or effect modifier on these relations.  相似文献   
108.
The nondystrophic myotonias are rare muscle hyperexcitability disorders caused by gain-of-function mutations in the SCN4A gene or loss-of-function mutations in the CLCN1 gene. Clinically, they are characterized by myotonia, defined as delayed muscle relaxation after voluntary contraction, which leads to symptoms of muscle stiffness, pain, fatigue, and weakness. Diagnosis is based on history and examination findings, the presence of electrical myotonia on electromyography, and genetic confirmation. In the absence of genetic confirmation, the diagnosis is supported by detailed electrophysiological testing, exclusion of other related disorders, and analysis of a variant of uncertain significance if present. Symptomatic treatment with a sodium channel blocker, such as mexiletine, is usually the first step in management, as well as educating patients about potential anesthetic complications.  相似文献   
109.
The role of dopamine in regulating sleep‐state transitions during, both natural sleep and under anaesthesia, is still unclear. Recording in vivo in the rat mPFC under urethane anaesthesia, we observed predominantly slow wave activity (SWA) of <1 Hz in the local field potential interrupted by occasional spontaneous transitions to a low‐amplitude‐fast (LAF) pattern of activity. During periods of SWA, transitions to LAF activity could be rapidly and consistently evoked by electrical stimulation of the ventral tegmental area (VTA). Spontaneous LAF activity, and that evoked by stimulation of the VTA, consisted of fast oscillations similar to those seen in the rapid eye movement (REM)‐like sleep state. Spontaneous and VTA stimulation‐evoked LAF activity occurred simultaneously along the dorsoventral extent of all mPFC subregions. Evoked LAF activity depended on VTA stimulation current and could be elicited using either regular (25–50 Hz) or burst stimulation patterns and was reproducible upon repeated stimulation. Simultaneous extracellular single‐unit recordings showed that during SWA, presumed pyramidal cells fired phasically and almost exclusively on the Up state, while during both spontaneous and VTA‐evoked LAF activity, they fired tonically. The transition to LAF activity evoked by VTA stimulation depended on dopamine D1‐like receptor activation as it was almost completely blocked by systemic administration of the D1‐like receptor antagonist SCH23390. Overall, our data demonstrate that activation of dopamine D1‐like receptors in the mPFC is important for regulating sleep‐like state transitions.  相似文献   
110.
KRAS oncogene mutations cause sustained signaling through the MAPK pathway. Concurrent inhibition of MEK, EGFR, and HER2 resulted in complete inhibition of tumor growth in KRAS-mutant (KRASm) and PIK3CA wild-type tumors, in vitro and in vivo. In this phase I study, patients with advanced KRASm and PIK3CA wild-type colorectal cancer (CRC), non-small cell lung cancer (NSCLC), and pancreatic cancer, were treated with combined lapatinib and trametinib to assess the recommended phase 2 regimen (RP2R). Patients received escalating doses of continuous or intermittent once daily (QD) orally administered lapatinib and trametinib, starting at 750 mg and 1 mg continuously, respectively. Thirty-four patients (16 CRC, 15 NSCLC, three pancreatic cancers) were enrolled across six dose levels and eight patients experienced dose-limiting toxicities, including grade 3 diarrhea (n = 2), rash (n = 2), nausea (n = 1), multiple grade 2 toxicities (n = 1), and aspartate aminotransferase elevation (n = 1), resulting in the inability to receive 75% of planned doses (n = 2) or treatment delay (n = 2). The RP2R with continuous dosing was 750 mg lapatinib QD plus 1 mg trametinib QD and with intermittent dosing 750 mg lapatinib QD and trametinib 1.5 mg QD 5 days on/2 days off. Regression of target lesions was seen in 6 of the 24 patients evaluable for response, with one confirmed partial response in NSCLC. Pharmacokinetic results were as expected. Lapatinib and trametinib could be combined in an intermittent dosing schedule in patients with manageable toxicity. Preliminary signs of anti-tumor activity in NSCLC have been observed and pharmacodynamic target engagement was demonstrated.  相似文献   
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