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101.
Interleukin-12: A bridge between innate resistance and adaptive immunity with a role in infection and acquired immunodeficiency 总被引:9,自引:0,他引:9
Interleukin-12 (IL-12) is a disulfide-linked heterodimeric cytokine originally identified as a product of EBV-transformed B cell lines. Monocyte/macrophages are the physiologically most relevant producers of IL-12, in response to both Gram-positive and -negative bacteria, bacterial products, and intracellular parasites. Although IL-12 has an enhancing effect on the survival and growth of early hematopoietic progenitor cells, most of the IL-12 biological activity has been described on T and NK cells, on which it induces production of lymphokines, primarily IFN-, enhances cytotoxic activity, and, in cooperation with other stimuli, increases proliferation. IL-12 is an inducer of development of T helper type 1 (Th-1) cells and the equilibrium between IL-12 and IL-4 is probably important for the balancein vivo between Th-1 and Th-2 responses. IL-12 has an important role in the host resistance to infection, in particular to intracellular pathogens, by activating macrophages through induction of IFN- from NK and T cells and by enhancing cell-mediated immune responses, dependent on Th-1 cell development. Peripheral blood mononuclear cells from HIV-seropositive individuals are impaired in their ability to produce IL-12 in response to bacterial stimulation, and IL-12 restoresin vitro some of the depressed immunological functions, suggesting that a defect in IL-12 production may have a pathogenic role in the immunodeficiency of HIV-infected individuals. Natural IL-12 appears to provide a regulatory link between innate resistance and the development of the antigen-specific adaptive immune response and the recombinant protein has therapeutic potential because of its activity against tumors and infections and its effectiveness as an adjuvant enhancing cell-mediated immunity in vaccination. 相似文献
102.
Thierry Berney M.D. Giorgio La Scala M.D. Denise Vettorel M.D. Dagmar Gumowski M.D. Conrad Hauser M.D. Pascal Frileux M.D. Dr. Patrick Ambrosetti M.D. Adrien Rohner M.D. 《Diseases of the colon and rectum》1994,37(10):1038-1042
PURPOSE: This paper intends to stress the importance of early diagnosis and discuss surgical treatment of Type IV Ehlers-Danlos syndrome (EDS-4), an autosomal dominant connective tissue disease characterized by typical features of the face and extremities, inappropriate and easy bruising, and extreme tissue fragility, which may lead to dramatic and often fatal complications, mostly spontaneous arterial or intestinal rupture. METHODS: We report the case of a 41-year-old female who presented with spontaneous perforation of the sigmoid colon. RESULTS: The patient was seen over a nine-year period, during which time she required six operations and presented with a great number of surgical complications including stenosis of an end-colostomy, repeated subocclusive episodes caused by intraperitoneal adhesions, and enterocutaneous fistulas, finally ending with an ileostomy and short bowel syndrome. It is only after a difficult laparotomy for ovarian cyst excision, marked by numerous adhesions and friable bowel, that the diagnosis of EDS-4 was considered and established. CONCLUSIONS: In case of “idiopathic” spontaneous perforation of the colon in a young adult, features of EDS-4 should be thoroughly looked into and, if found, skin fibroblast culture with collagen Type III analysis performed. The surgical treatment of choice consists of subtotal colectomy and permanent endileostomy. In case of patient refusal, a second-stage ileorectal anastomosis can be performed but carries the high risk of anastomotic leakage. 相似文献
103.
Paolo E. Levi-Setti Giulia Rognoni Maddalena Bozzo Guglielmo Ragusa Patrizia Sulpizio Enrico Ferrazzi Giorgio Pardi 《Journal of assisted reproduction and genetics》1995,12(7):413-417
Objectives To evaluate uterine artery resistance during multiovulation induction in relation to the implantation rate in patients attendingin vitro fertilization (IVF) cycles.Patients Multiovulation induction for IVF was monitored by daily determination of the pulsatility index (PI) of the uterine arteries, obtained by a transvaginal probe (6.5 MHz) implemented with color-flow imaging. Doppler data were obtained from 5 days before hCG administration to the day of follicular aspiration. One IVF cycle was monitored in 70 patients. In 17 patients, 41 IVF cycles were monitored until a successful attempt occurred.Results In the 70 patients studied during one IVF attempt, the PI of the uterine arteries significantly varied (P < 0.001) in the different phases of the cycle. In the 24 patients who conceived, a significantly lower PI (P < 0.03) was found throughout the cycle. This result was mainly due to a highly significant difference of PI values observed the day after hCG administration (P < 0.005). In the 17 patients who conceived after 1 to 4 negativein vitro fertilizations, no significant difference in PI was observed in the uterine artery resistance in cycles in which implantation was or was not successful.Conclusions Uterine artery resistance varies significantly during phases of the induction therapy. Uterine artery resistance is lower throughout the course of multiovulation induction in patients with higher pregnancy rates. The PI on the day after hCG administration was the best index of pregnancy rate. Low uterine artery resistance was present even in negative attempts in patients who eventually achieved a successful implantation. PI values 3 can be considered a favorable prognostic factor for future IVF cycles.Presented at the 49th Annual Meeting of the American Fertility Society, Montreal, 1993 and the 50th Annual Meeting of the American Fertility Society, November 5–10, 1994, San Antonio, Texas. 相似文献
104.
Giorgio Gabella 《Journal of neurocytology》1995,24(3):159-187
Summary Intramuscular nerve fibres in the bladder of adult female rats were investigated by means of serial sections. The following observations were made. (1) Upon penetrating into the musculature the nerve bundles branch repeatedly, and almost all turn into single fibres; their axons become varicose, the Schwann cell sheath is attenuated, incomplete or absent, and the separation between axonal membrane and muscle cell membrane is reduced to tens of nanometres. (2) All single axons, and some of those within bundles, are varicose, but the characteristic of being varicose is expressed by degrees, and is not an all-or-none state. (3) Varicosities contain vesicles (mostly of the agranular type), microtubules (with little connection with the axolemma or the vesicles), some neurofilaments (scarce or absent in the best developed varicosities), mitochondria (whose size is on average smaller than those of the perikaryon, and a minute amount of endoplasmic reticulum. (4) Terminal varicosities, the true anatomical ending of an axon, are often devoid of Schwann cell sheath, are packed with vesicles, rarely contain microtubules or neurofilaments, and lie close to a muscle cell: the gap is often reduced to 10 nm. (5) Schwann cells accompany the axons within the muscle strands. Unlike the area of the axonal profiles, the area of glial sheath changes little along the length of the nerve fibre, except towards its end. (6) The Schwann cell sheath around a varicosity is often incomplete; the area of the axolemma thus exposed is covered by the basal lamina, and is here referred to as a window. While some varicosities have a window only a few tens of nanometres in width, others have more than one window, and some are devoid of Schwann cell altogether, so that their entire axolemma is in contact with the basal lamina. The Schwann cell never extends beyond the axon, whereas very often (and possibly always) the axon extends beyond the Schwann cell. (7) Intervaricose segments vary in length and diameter, the narrowest ones accompanying the more clear-cut varicosities. Some intervaricose segments are as small as 50 nm in diameter, contain a single microtubule and lack a Schwann cell sheath. Others, sheathed by a Schwann cell, contain a single neurofilament or no organelles at all. (8) Specialized contacts between an axon and a muscle cell (neuro-muscular junctions) are abundant and are identified by four features: the axon is a varicosity packed with vesicles; the axolemma is exposed (presence of a window); the distance between the two membranes ranges between 10 and 100 nm, mostly 30–50 nm; and the intercellular gap excludes fibrils, such as collagen, but is occupied by a single basal lamina. Any of these parameters, however, can also occur uncoupled (windows on intervaricose segments; varicosities without a window; exposed axolemma far from a muscle cell). (9) There are no direct contacts between axons. Even when they run close to each other within a bundle, they are always separated by a Schwann cell process. (10) The muscle cell membrane is concave beneath the varicosities; however, the muscle cell ultrastructural features in the region of the neuro-muscular junction are not different from those in other regions of the cell. (11) On average there is more than one neuro-muscular junction per muscle cell, and examples of muscle cells receiving multiple nerve endings from one or from two axons are picked up by the serial sections. (12) A striking feature of the bladder innervation is the variability of its ultrastructural parameters. The bladder innervation does not appear to be built on a rigid structural plan, and the notion of loose-patterned innervation is presented. 相似文献
105.
Vercellini Paolo; Parazzini Fabio; Oldani Sabina; Panazza Stefania; Bramante Tiziana; Crosignani Pier Giorgio 《Human reproduction (Oxford, England)》1995,10(5):1160-1162
To evaluate the prevalence and risk factors for adenomyosis,the clinical records of consecutive women undergoing hysterectomyduring a 3 year period were retrieved. Data were collected onindication for the intervention, general sociodemographic characteristicsof the patients, age at menarche, parity, abortions, and menopausalstatus at surgery. Adenomyosis was diagnosed in 332 of the 1334cases (24.9%). The condition was present in 146 of the 627 patients(23.3%) with fibroids and menorrhagia, 68 of the 265 (25.7%)with prolapse, 21 of the 98 (21.4%) with ovarian cysts, 19 ofthe 100 (19%) with cervical cancer, 31 of the 110 (28.2%) withendometrial cancer, 16 of the 57 (28.1%) with ovarian cancer,and 19 of the 77 (24.7%) with miscellaneous indications. Thesedifferences were not statistically significant (x26 = 11.14).In comparison with nulliparous women, the odds ratio was 1.3and 1.5 respectively in women with one and two births (x21 trend= 5.76, P < 0.05). No relationship was found between ageat surgery, age at menarche, indications for surgery, menopausalstatus at intervention, and presence of endometriosis. Our findingsdo not support the notion that adenomyosis is more frequentlyrelated to particular clinical conditions, and suggest thatparity may be associated with an increased frequency of adenomyosis. 相似文献
106.
Dr. Maurizio Vaglini MD Dr. Filiberto Belli MD Mario Santinami MD Flavio Arienti MD Giorgio Parmiani MD Laura Persiani MD Nicola Santoro MD Maria Grazia Inglese MD Fortunato D'Elia MD Natale Cascinelli MD 《Annals of surgical oncology》1995,2(1):61-70
Background: Therapies of advanced melanoma patients with interleukin-2 (IL-2) and cytotoxic lymphocytes have produced interesting results, but a larger diffusion of these treatments is limited by the severe side effects due to IL-2 systemic infusion. A strictly regional administration of IL-2 and cells by an isolation perfusion (IP) in extracorporeal circulation (ECC) for the treatment of regional melanoma metastases could improve tolerability and efficacy of this specific modality of immunotherapy.
Methods: Ten patients were submitted to adoptive immunotherapy with IL-2 and lymphokine-activated killer (LAK) cells by IP in ECC. The schedule of treatment included the first course of a 5-day systemic administration of IL-2 (Proleukin, EuroCetus 9–12 × 106 IU/M2/day continuous infusion); autologous LAK cells were obtained via leukapheresis and after in vitro activation were given (range 8–28 × 109) along with IL-2 (120-2,400 IU/ml of perfusion priming) to the affected limb by IP; IL-2 (9–12×106 IU/m2/day) was also administered by systemic continuous infusion for 5 days starting on the day after IP.
Results: All patients concluded the treatment without any major local or systemic toxicities. Clinical responses included one complete and six partial remissions; three patients had stable disease. All patients are alive. Follow-up after IP ranged from 12 to 35 months (median: 22). The analysis of circulating lymphocytes revealed the rapid disappearance of LAK cells, suggesting their extravasation and/or endothelial adhesion in perfused tissues.
Conclusions: IP with IL-2 and LAK cells is a new approach for the treatment of in-transit metastases due to cutaneous melanoma. The treatment appears to be feasible and reliable. Further biological and immunological studies should permit amelioration of the present modality of treatment. 相似文献
107.
Giant abdominopelvic epithelioid angiomyolipoma associated with tuberous sclerosis: Report of a case
Giorgio Di Matteo Alessandro Maturo Antonella Marzullo Nadia Peparini Bianca Martin Wedard Kenneth Paul Zeri Filippo Maria Di Matteo Domenico Mascagni 《Surgery today》1999,29(11):1183-1188
(Received for publication on July 16, 1998; accepted on Mar. 11, 1999) 相似文献
108.
Bronz G 《Aesthetic plastic surgery》1999,23(6):424-427
Five hundred ten implants were used in 273 patients. The follow-up was between 3 months and 8 years. Four hundred nineteen
prostheses were used for subglandular breast augmentation, 91 for subpectoral breast reconstruction. All the breasts were
checked personally: 397 augmented breasts and 86 reconstructed breasts—94.7%. The objective criterion was the Baker classification:
grades I and II, good result; and grades III and IV, poor result. Results were as follows: Baker I, 397 breasts; Baker II,
78 breasts (I + II, 98.3%); Baker III, 5 breasts; Baker IV, 3 breasts (III + IV, 1.7%). Three prostheses were removed after
3, 4, and 6 years because the textured surface was totally damaged. Two bilumen prostheses lost the saline fluid. The complication
rate due to the implants was very low. 相似文献
109.
Prevalence and clinical relevance of Blastocystis hominis in diverse patient cohorts 总被引:3,自引:0,他引:3
Oscar Cirioni Andrea Giacometti Davide Drenaggi Fausto Ancarani Giorgio Scalise 《European journal of epidemiology》1999,15(4):387-391
The pathogenicity of Blastocystis hominis is extensively debated in the medical literature. Therefore, we did a prevalence study to investigate the association between the presence of several intestinal parasites and gastrointestinal symptoms in diverse patient cohorts. The study population consisted of 1216 adults, including immunocompromised patients, institutionalized psychiatric or elder subjects, immigrants from developing countries, travellers to developing tropical countries and controls. Several variables for each risk group were considered. Stools specimens, collected in triplicate, were processed by the same technicians. Clinical data about each subject were provided by standardized questionnaires. The presence of gastrointestinal symptoms were related to the presence of any parasite. In addition, on the basis of microbiological results, five subgroups of subjects were evaluated. The results showed a high prevalence of parasites in all the risk groups. Immunocompromised status, recent arrival from developing countries and the presence of behavioural aberrations were significantly related to presence of parasites. B. hominis was the parasite most frequently detected in each studied group. B. hominis showed a significant correlation with gastrointestinal symptoms only when detected in the group including subjects with a severe immunodepression. Immunodepression seems to be a factor of primary importance of the pathogenic role of B. hominis. 相似文献
110.
Patterns of practice for acute myocardial infarction in a population from ten countries 总被引:4,自引:0,他引:4
Background: There is conclusive evidence from large scale randomized clinical trials (RCTs) that several treatments administered in
the acute phase of a myocardial infarction (AMI) reduce mortality. However, only a minority of patients admitted with AMI
receives at the appropriate treatments.
Objectives: This study aims at (1) describe the utilization patterns for AMI; (2) determine the appropriateness of prescribing, measured
as adherence to the ACC/AHA guidelines; and (3) determine which factors are associated with the administration of thrombolytic
agents.
Methods: The study was a multi-center survey carried out in ten countries (nine European and one Canadian province) over a 3-month
period. Data were prospectively collected by clinical pharmacists. All consecutive patients admitted to the participating
hospitals during the study period with a diagnosis of suspected AMI were included in the study. Rates of use were calculated
as “overall utilization” and “adjusted utilization” (e.g., accounting for eligibility).
Results: Data were available on 1976 patients from 56 participating centers. The mean age of the patients was 65 years (range 25–95,
SD = 12.6) and 29.7% were women. Adjusted utilization rates were 63.7% for thrombolysis, 88% for aspirin, and 65.9% for β-adrenergic
blocking agents. The most utilized thrombolytic agent was streptokinase (65.9%). The main reasons given by physicians for
not administering thrombolysis was the delay from chest pain onset to admission. Patients admitted to teaching hospitals were
less likely to receive aspirin than patients admitted to general hospitals (adjusted rate 90.1% vs 86%, P = 0.007), but they were more likely to undergo a primary invasive procedure (11.0% vs 2.5% P = 0.001). Multivariate analysis showed that age greater than 74 years, delay, prior myocardial infarction, and Killip scale
were correlated with the non-utilization of thrombolysis.
Conclusion: Recommended treatments are still underutilized in patients with AMI. Increased utilization is required, particularly for
elderly people. There is a wide variability among hospitals with different affiliations (teaching vs non teaching), demonstrating
the different patterns of practice in various settings.
Received: 2 February 1998 / Accepted in revised form: 8 August 1998 相似文献