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51.
Differential coupling of CC chemokine receptors to multiple heterotrimeric G proteins in human interleukin-2-activated natural killer cells 总被引:2,自引:1,他引:2
Using two different approaches, we have investigated the types of G proteins coupled to CC chemokine receptors. First, permeabilization of interleukin-2-activated natural killer (IANK) cells with streptolysin-O and introduction of anti-G protein antibodies inside these cells resulted in the following. (1) Anti-G(s), anti-G(o), and anti-G(z) inhibited the migration of IANK cells in response to macrophage- inflammatory protein-1 alpha (MIP-1 alpha), monocyte chemoattractant protein-1 (MCP-1), or regulated on activation normal T cell expressed and secreted (RANTES). (2) Anti-Gi inhibited their migration in response to MCP-1 or RANTES but not in response to MIP-1 alpha. Second, incubation of IANK cell membranes with anti-G protein antibodies before incubating with (gamma-35S) GTP or (gamma-32P) GTP, resulted in the following. (1) Anti-G(s), anti-G(o), or anti-G(z) inhibited GTP binding and GTPase activity in the presence of MIP-1 alpha, or RANTES. (2) Anti- G(i) inhibited GTP binding and GTPase activity in the presence of MCP-1 or RANTES but not in the presence of MIP-1 alpha. The inhibitory effect of anti-G protein antibodies was reversed upon incubating these antibodies with their respective synthetic peptides before addition to IANK cell membranes. These results suggest that MCP-1 and RANTES receptors are promiscuously coupled to multiple G proteins in IANK cell membranes and that this coupling is different from MIP-1 alpha receptors, which seem to be coupled to G(s), G(o), and G(z) but not to G(i). 相似文献
52.
Cardoso AA; Schultze JL; Boussiotis VA; Freeman GJ; Seamon MJ; Laszlo S; Billet A; Sallan SE; Gribben JG; Nadler LM 《Blood》1996,88(1):41-48
Even if neoplastic cells express tumor associated antigens they still may fail to function as antigen presenting cells (APC) if they lack expression of one or more molecules critical for the induction of productive immunity. These cellular defects can be repaired by physiologic activation, transfection, or fusion of tumor cells with professional APC. Although such defects can be repaired, antitumor specific T cells may still fail to respond in vivo if they may have been tolerized. Here, human pre-B cell acute lymphoblastic leukemia (pre-B ALL) was used as a model to determine if primary human tumor cells can function as alloantigen presenting cells (alloAPC) or alternatively whether they induce anergy. In the present report, we show that pre-B cell ALL express alloantigen and adhesion molecules but uniformly lack B7-1 (CD80) and only a subset express B7-2 (CD86). Pre-B ALL cells are inefficient or ineffective alloAPC and those cases that lack expression of B7-1 and B7-2 also induce alloantigen specific T- cell unresponsiveness. Under these circumstances, T-cell unresponsiveness could be prevented by physiologic activation of tumor cells via CD40, cross-linking CD28, or signaling through the common gamma chain of the interleukin-2 receptor on T cells. Taken together, these results suggest that pre-B ALL may be incapable of inducing clinically significant T-cell-mediated antileukemia responses. This defect may be not only due to their inability to function as APC, but also due to their potential to induce tolerance. Attempts to induce clinically significant antitumor immune responses may then require not only mechanisms to repair the antigen presenting capacity of the tumor cells, but also reversal of tolerance. 相似文献
53.
Francesco Vairo Emanuele Nicastri Salma Masauni Yussuf Angela Cannas Silvia Meschi Mwanakheir AA Mahmoud Azza H. Mohamed Paul Mohamed Maiko Pasquale De Nardo Nazario Bevilacqua Concetta Castilletti Antonino Di Caro Vincenzo Racalbuto Giuseppe Ippolito 《Emerging infectious diseases》2014,20(3):465-468
We conducted a seroprevalence survey among 500 healthy adult donors at Zanzibar National Blood Transfusion Services. Dengue virus IgG seroprevalence was 50.6% and independently associated with age and urban residence. These data will aid in building a surveillance, preparedness, and response plan for dengue virus infections in the Zanzibar Archipelago.Key words: dengue, seroprevalence, Zanzibar, viruses, vector-borne infections 相似文献
54.
Ergunay K Tezel GG Dogan AI Ozen H Sirin G Ozbay M Karabulut E Ustacelebi S 《Pathology, research and practice》2008,204(9):649-653
Human Parvovirus B19 has previously been implicated in the pathogenesis of testicular germ cell tumors, but this could not have been confirmed. This study was designed to investigate the testicular persistence of Parvovirus B19 and possible associations with germ cell tumors. Paraffin-embedded or fresh tissues from 36 germ cell tumors, 20 germ cell aplasias, 26 normal testicular tissues, 20 liver tissues, and 20 spleen tissues were evaluated by two different molecular assays: a nested PCR for Parvovirus B19 capsid genes and a commercial quantitative real-time PCR. Positive results were further confirmed by another commercial real-time PCR assay. Viral DNA was detected in 3 of 36 (8.3%) germ cell tumors, but not in other groups. Viral loads observed in all positive samples were less than 20 IU/reaction, suggesting very low levels of viral replication or latency. These results either directly or indirectly imply the involvement of Parvovirus B19 with testicular germ cell tumors. Viral persistence in normal testis, germ cell aplasia tissues, or hepatic/splenic tissues was not observed in this study. 相似文献
55.
Büyükmumcu M Ustün ME Seker M Karabulut AK Uysal YY 《Surgical and radiologic anatomy : SRA》2003,25(5-6):368-371
The possibility for maxillary artery (MA) to petrous internal carotid artery (ICA) bypass was investigated. Five adult cadavers were dissected bilaterally. After zygomatic arch osteotomy, the coronoid process was sectioned at its base. An extensive infratemporal craniotomy was performed at the level of foramina ovale, rotundum and spinosum. The petrous portion of the ICA was exposed by drilling away the floor of the middle fossa, posterior to the foramen ovale and medial to the foramen spinosum. The MA was identified medial to the infratemporal crest and was followed in the pterygopalatine fossa, then transected at the origin of the infraorbital artery. The MA graft was brought posteromedially to reach the petrous ICA. The mean caliber of the MA before the origin of the infraorbital artery was 2.54±0.31 mm, 2.76±0.14 mm at the site of anastomosis, and 3.46±0.32 mm after giving off the middle meningeal artery. The average length of the MA between the middle meningeal artery and the infraorbital artery was 43.4±2.35 mm, and up to the site of anastomosis was 37.64±1.68 mm. We conclude that the length and diameter of the MA are sufficient for a tension-free anastomosis between MA and petrous ICA, and such a procedure could be used in the treatment of patients with tumors of the infratemporal fossa invading the high cervical ICA.
Electronic Supplementary Material The french version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at
Electronic Supplementary Material The french version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at
Étude anatomique des possibilités de by-pass entre la partie pétreuse de l'artère carotide interne et l'artère maxillaire
Résumé La possibilité d'un by-pass entre l'artère maxillaire et la partie pétreuse de l'artère carotide interne a été étudiée. Cinq cadavres adultes ont été disséqués des deux côtés. Après ostéotomie de l'arcade zygomatique, le processus coronoïde était sectionné à sa base. Une large craniotomie infra-temporale était effectuée au niveau du foramen ovale, du foramen rond et du foramen épineux. La partie pétreuse de l'artère carotide interne était exposée par fraisage du plancher de la fosse cérébrale moyenne, en arrière du foramen ovale et en dedans du foramen épineux. L'artère maxillaire était identifiée en dedans de la crête infra-temporale et suivie dans la fosse ptérygo-palatine, puis sectionnée à l'origine de l'artère infra-orbitaire. Le greffon d'artère maxillaire était transposé en dedans et en arrière pour atteindre la partie pétreuse de l'artère carotide interne. Le calibre moyen de l'artère maxillaire était de 2,54±0,31 mm à l'origine de l'artère infra-orbitaire, 2,76±0,14 mm au niveau de l'anastomose, et 3,46±0,32 mm après la naissance à l'artère méningée moyenne. La longueur moyenne de l'artère maxillaire entre l'artère méningée moyenne et l'artère infra-orbitaire était de 43,4±2,35 mm et au-delà du site d'anastomose était de 37,64±1,68 mm. Nous en avons conclu que la longueur et le diamètre de l'artère maxillaire était suffisant pour une anastomose sans tension entre l'artère maxillaire et la partie pétreuse de l'artère carotide interne. Ainsi, une telle technique pourrait être utilisée pour le traitement de patients porteurs d'une tumeur de la fosse infra-temporale envahissant la partie cervicale haute de l'artère carotide interne.相似文献
56.
JY Nagata TF Rocha‐Lima BP Gomes CC Ferraz AA Zaia FJ Souza‐Filho A De Jesus‐Soares 《Australian dental journal》2015,60(3):416-420
Immature avulsed teeth are not usually treated with pulp revascularization because of the possibility of complications. However, this therapy has shown success in the treatment of immature teeth with periapical lesions. This report describes the case of an immature replanted tooth that was successfully treated by pulp revascularization. An 8‐year‐old boy suffered avulsion on his maxillary left lateral incisor. The tooth showed incomplete root development and was replanted after 30 minutes. After diagnosis, revascularization therapy was performed by irrigating the root canal and applying a calcium hydroxide paste and 2% chlorhexidine gel for 21 days. In the second session, the intracanal dressing was removed and a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate was placed as a cervical barrier at the entrance of the root canal and the crown was restored. During the follow‐up period, periapical repair, apical closure and calcification in the apical 4 mm of the root canal was observed. An avulsed immature tooth replanted after a brief extra‐alveolar period and maintained in a viable storage medium may be treated with revascularization. 相似文献
57.
Ilhan Karabicak Kagan Karabulut Savas Yuruker Tugrul Kesicioglu Necati Ozen 《The Indian journal of surgery》2017,79(2):111-115
Single-port laparoscopic surgery has the advantage of a hidden scar and reduced abdominal wall trauma. Although single-port laparoscopic surgery is widely performed for other organs, its application is very limited for liver resection. Here, we report our experience with nine patients who underwent single-port laparoscopic liver resection. Nine patients underwent single-port laparoscopic liver resection for the indications of hydatid cyst, hepatocellular carcinoma, and colorectal cancer liver metastasis. Nine patients were successfully treated with single-port laparoscopic surgery. The operative time was between 60 and 240 min. The only operative complication was bleeding up to 650 mL in a patient with cirrhosis. No postoperative complications occurred. All patients were discharged earlier than usual. Single-port laparoscopic liver surgery is a challenging surgery. Surgeon with the experience of laparoscopic liver surgery should perform the single-port laparoscopic liver surgery. It is technically feasible with a good outcome in well-selected patients. Initial cases must be benign lesions to avoid jeopardizing oncological safety. 相似文献
58.
Ivana T. Croghan PhD Sandhya Pruthi MD J. Taylor Hays MD Stephen Cha MS Ruth E. Johnson MD Marianne Kosel AA Richard Morris BA Richard D. Hurt MD 《The breast journal》2009,15(5):489-495
Abstract: The purpose of this study was to assess the predictive value of smoking history on breast cancer diagnosis in a referral clinic population. We conducted a case–control study using clinical data collected on 8,097 female patients (1,225 breast cancer cases and 6,872 controls) seen in the Mayo Clinic Breast Clinic between August 1, 1993 and November 31, 2003. Breast cancer patients and noncancer patients significantly differed with respect to age at time of the index visit (p < 0.001), number of pregnancies (p = 0.006), number of live births (p = 0.002), vital status at last known follow-up (p < 0.001), current menstruation (p < 0.001), age at menopause (p < 0.001), history of hysterectomy (p < 0.001), use of oral contraception (p = 0.05), duration of oral contraception use (p = 0.001), use of other exogenous hormones (p < 0.001), duration of exogenous hormone use (p = 0.05), breast pain at time of index visit (p = 0.002), smoking status (p < 0.001), and use of five or more alcoholic beverages per week (p = 0.002). After adjustment for these baseline characteristics, having a personal history of smoking was found to be predictive of breast cancer diagnosis (odds ratios [OR] = 1.25, p = 0.004). Other positive predictors for breast cancer diagnosis were: age (OR = 1.02, p < 0.001), history of hysterectomy (OR = 0.66, p < 0.001), prior use of oral contraception for more than 11 years (OR = 2.10, p < 0.001), and prior use of other exogenous hormones/estrogen (OR = 1.81, p < 0.001). In this referral practice having a personal history of smoking is predictive of breast cancer diagnosis. Further studies are needed to further explore this relationship. 相似文献
59.
60.
Erhan Tenekecioğlu M.D. Aziz Karabulut M.D. Mustafa Yılmaz M.D. 《Echocardiography (Mount Kisco, N.Y.)》2010,27(6):677-686
Increased blood pressure (BP) is associated with an increase in cardiovascular mortality and morbidity. We aimed to analyze the effect of increased BP onto the function of left atrial appendage (LAA) in early stages of hypertension. Transesophageal echocardiography (TEE) was prospectively performed to assess LAA functions in 120 patients with increased BP, and in 58 normotensive subjects without cardiovascular disease. Patients with increased BP were divided according to Joint National Committee VII (JNC VII) report: prehypertensive,stage‐1 hypertensive and stage‐2 hypertensive patients. During TEE, LAA late‐emptying velocities (LAAEV) were significantly reduced only in stage‐2 hypertensives as compared with control group (P < 0.001). In contrast, LAA late‐contracting velocity (LAA TDI‐D2) was significantly reduced in prehypertensive,stage‐1 hypertensive and stage‐2 hypertensive patients, when compared with control group (P < 0.05, P < 0.001, and P < 0.001, respectively). The LAA maximal areas were increased significantly only in stage‐2 hypertensive patients when compared with control group (P < 0.05). During TEE, left atrial spontaneous echocardiographic contrast was found in 2 of 36 patients in prehypertension group, in 7 of 40 patients in stage‐1 hypertension group, and in 10 of 44 patients in stage‐2 hypertension group. Left atrial thrombi were observed in 3 (6.8%) patients of stage‐2 hypertension group. In conclusion, in patients with untreated prehypertension and hypertension, elevation of afterload imposed on left atrium involved both left atrium and LAA, resulting in impairment of the LAA function. Tissue Doppler imaging (TDI) enables the detection of this functional impairment in early stages of hypertension, even in prehypertensive phase, when compared with conventional Doppler flow measurement of the LAA. Even in prehypertensive phase, BP should be decreased to normal levels to prevent the LAA dysfunction. (Echocardiography 2010;27:677‐686) 相似文献