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41.
Transplantation of any organ has some inherent risk of disease transmission, such as infection and malignancy. The present study aims to describe 2 cases of choriocarcinoma transmission after kidney and liver transplantation originating from the same patient. The donor was a 17-year-old woman who died of cerebral hemorrhage. Both organ recipients died of metastatic choriocarcinoma few months after the transplantation, within days after starting chemotherapy. Retrospective hCG (human chorionic gonadotropin hormone) analysis in donor's blood stored at the time of donation had a result of 9324 mIU/mL. Despite its rarity, clinicians should be aware of the risk of transplant-related choriocarcinoma from female donors in childbearing age. In some cases, hCG dosage should be performed before donation.  相似文献   
42.
The metastatic process is characterized by a complex series of sequential steps involving constant interactions (mutual cross-talks) of metastasized tumor cells with their microenvironment (lymphocyte, macrophages, endothelial cells, etc.) in target organs. These interactions determine the outcome of metastasis (either the eradication of metastatic cells or their increased proliferation and invasion). Recently developed methods of tumor and host cell analysis at the molecular level allow better elucidation of molecular mechanisms of metastasis and of immune mechanisms involved in antitumor responses. Direct modulation of these processes will probably increase the success of clinical cancer treatment. Here we review data (a) on the expression of some costimulatory (MHC class II, CD80, sialoadhesin) and adhesion (LFA1, ICAM-1, VLA-4) molecules on both metastasized tumor cells and host cells and (b) on the production of a cytotoxic molecule, nitric oxide, by in situ activated Kupffer and endothelial cells in the process of liver metastasis. This study was performed with well-characterized murine ESbL T lymphoma cells transduced with the bacterial lacZ gene, which allows detection and quantification of metastases at the single cell level throughout lymphoma growth and metastasis. Experimental results are discussed in the context of recent literature.Abbreviations APC Antigen-presenting cells - hCRP Human C-reactive protein - ICAM Intercellular adhesion molecule - IFN Interferon - IL Interleukin - iNOS Inducible NO synthase - LFA Leukocyte function associated antigen - SER Sheep erythrocyte receptor - TA Tumor-associated rejection antigens - TNF Tumor necrosis factor - VCAM Vascular cell adhesion molecule - VLA Very late activated antigen  相似文献   
43.
A cellular cancer therapy is described with unique efficiency even in late-stage disease. in situ activated tumor-immune T cells, induced in allogeneic, tumor-resistant, MHC identical but superantigen different donor mice (B10.D2) could transfer strong graft-versus-leukemia (GvL) effects accompanied by only mild graft-versus-host (GvH) reactivity. Systemic immune cell transfer into 5 Gy irradiated DBA/2 mice bearing up to 4 week established syngeneic tumors and macrometastases led to massive infiltration of tumor tissues by CD4 and CD8 donor T lymphocytes. Upon interaction of immune CD4 donor T cells with host antigen presenting cells in synergy with immune CD8 donor T cells attacking the tumor cells directly, primary tumors (1.5 cm diameter) were encapsulated and rejected from the skin and liver metastases eradicated. For the first time, such adoptive cellular immunotherapy (ADI) was followed in individual live animals by P-31-NMR spectroscopy of primary tumors. An approximately 25,000 fold excess of metastatic tumor cells could be rejected as revealed quantitatively by FACScan analysis of lacZ gene transfected tumor cells.  相似文献   
44.
We studied nitric oxide (NO) production, adenosine deaminase (ADA) and 5'-nucleotidase (5-N) activity as a function of macrophage activation in the model of spontaneous metastasis of ESbL T lymphoma cells transduced with the lacZ gene. Liver and spleen macrophages were isolated and examined directly ex vivo without further experimental manipulation. Transient arrest of liver metastasis was accompanied by an increase of NO production and ADA activity and by a decrease of 5-N activity. An aggressive expansion of metastasis was correlated with a drop of NO production and ADA activity and with an increase of 5-N activity. To test the involvement of in situ activated Kupffer cells in an antimetastatic response, two immunotherapy protocols were used: i) active immunization with lymphoma cells and ii) adoptive transfer of antitumor immune spleen cells. Both treatments caused an upregulation of ADA activity and NO production in Kupffer cells, which correlated with host resistance against metastases.  相似文献   
45.
INTRODUCTION: The register of death by cause, sex and age groups of residents in 1994 in Rio Grande do Sul (RS) and Santa Catarina (SC), two Brazilian southern states, were studied to calculate the years of life lost (YLL), one of the two components that summarize disability adjusted life years (DALY), in RS, SC and Brazil. METHODS: The methodology employed is the same used in the Global Burden of Disease study to quantify the mortality component (YLL) of DALY in the world. RESULTS: The results show that the greatest proportion and rates caused by Group II (Noncommunicable diseases), linked with more advanced stages of the epidemiological transition, in RS, SC and Brazil. But in both states and especially in Brazil, Group I (Communicable, maternal, perinatal and nutritional conditions) causes an important proportion of YLL. The Group III (Injuries) was the second more important group in RS and SC and the third in Brazil. Road traffic accidents are particularly important in SC, where the intentional injury rate is half than the one in RS. The leading causes of YLL were road traffic accidents, ischemic heart disease and cerebrovascular disease in SC, and ischemic heart disease, cerebrovascular disease and road traffic accidents in RS. CONCLUSIONS: Death certification in the southern region of Brazil has a complete coverage and miscoded death proportion is small, providing a reliable mortality information. DALY allow comparing fatal and nonfatal health outcomes to determine the importance of different diseases and to establish health priorities. DALY are also an useful tool to identify disadvantaged groups, target health interventions and provide information for social control of resource allocation.  相似文献   
46.
Neonatal care has improved greatly in recent years, focusing its efforts on low weight and premature children. Literature has considered prematurity under several focuses, recommending the following of growth and development in a systematic way. The present study tries to present a review of the literature on nursing care in the follow-up to premature children, in order to promote a reflection about the health care given to this customers. Authors searched in the data bank of the University of S?o Paulo, international periodicals and recent books. In general, studies focus on nursing role and strategies, such as home visits, in order to provide follow-up for the children and give orientations to mothers, as well as give support to the families. Studies emphasize the importance of multiprofessional teams working with mothers, children and families from neonatal intensive care to the post-neonatal period. The following of children brings out the need of reorganization and integration of health services, as well as the improvement of the relationships between professionals and families. Therefore, it is important to characterize the follow-up of this children, enabling the way for a more effective role in nursing care.  相似文献   
47.
The lack of well established dosimetry protocols for HDR sources is a point of great concern regarding the uniformity of procedures within a particular country and worldwide. The main objective of this paper is to report the results from ten institutions of an intercomparison of calibration procedures for 192Ir HDR sources currently in use in Brazil. The treatment irradiator of one institution was calibrated by a reference system and used by all participants with their own measuring electrometers and ionization chambers under the same experimental conditions. Two methods were used: the calibration jig and the well-type ionization chamber. Each participant was allowed to use their own method and formalism. The results of this exercise were very positive since this was the first time in Brazil that a group of users gathered to share their experience and openly discuss the physical concepts behind the calibration procedures. The results were all within +/-3.0%, except one case where -4.6% was observed and later identified as a problem with the Nk value for x-rays. Though the magnitude of the deviations found was generally acceptable considering the diversity of formalisms currently in use, a proposal is now being prepared to be adopted as a national protocol. The identification of the institutions was left out for the sake of confidentiality.  相似文献   
48.
In December 2019, a new viral respiratory infection known as coronavirus disease 2019 (COVID-19) was first diagnosed in the city of Wuhan, China. COVID-19 quickly spread across the world, leading the World Health Organization to declare it a pandemic on March 11, 2020. The disease is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a similar virus to those involved in other epidemics such as severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Epidemiological studies have shown that COVID-19 frequently affects young adults of reproductive age and that the elderly and patients with chronic disease have high mortality rates. Little is known about the impact of COVID-19 on pregnancy and breastfeeding. Most COVID-19 cases present with mild flu-like symptoms and only require treatment with symptomatic relief medications, whereas other cases with COVID-19 require treatment in an intensive care unit. There is currently no specific effective treatment for COVID-19. A large number of drugs are being used to fight infection by SARS-CoV-2. Experience with this therapeutic arsenal has been gained over the years in the treatment of other viral, autoimmune, parasitic, and bacterial diseases. Importantly, the search for an effective treatment for COVID-19 cannot expose pregnant women infected with SARS-CoV-2 to the potential teratogenic risks of these drugs. Therefore, it is necessary to determine and understand the safety of anti-COVID-19 therapies prior to conception and during pregnancy and breastfeeding.Key words: COVID-19, SARS-CoV-2, antiviral, pregnancy, breastfeeding  相似文献   
49.
BACKGROUND: It has been suggested that measurement of continuous cardiac output (CCO) is an advancement in the management of critically ill patients. Our objective was to determine the accuracy of CCO during the rapid hemodynamic changes induced by hemorrhage and resuscitation. METHODS: In 12 anesthetized dogs (20.2+/-0.9 kg), pulmonary artery blood flow, our "gold standard" cardiac output, was measured with an sonographic flowprobe, whereas CCO, intermittent bolus cardiac output (ICO), and mixed venous oxygen saturation were measured with a thermodilution fiberoptic pulmonary artery catheter with a thermal filament. A graded hemorrhage (20 mL/min) was produced to a mean arterial pressure of 40 mm Hg, which was maintained at this level for 30 minutes. Total shed blood volume (701+/-53 mL) was retransfused at a rate of 40 mL/min, over 30 minutes, after which a massive hemorrhage (100 mL/min) was produced over 10 minutes. RESULTS: Hemorrhage induced significant decreases in mean arterial pressure, mixed venous oxygen saturation, and oxygen delivery, which were all restored during early resuscitation. However, CCO showed a delayed response after hemorrhage and resuscitation, compared with pulmonary blood flow, throughout the study (r = 0.549), matching only at baseline and at the end of both graded hemorrhage and resuscitation periods. There was a good correlation between ICO and pulmonary artery blood flow (r = 0.964) and no significant differences between them throughout the study. CONCLUSION: CCO has a delayed response during acute hemodynamic changes induced by hemorrhage and resuscitation. When sudden changes in mean arterial pressure or in mixed venous oxygen saturation are detected, cardiac output must be estimated by the standard bolus thermodilution technique, not by CCO.  相似文献   
50.
Sj?gren's syndrome is a complex autoimmune disorder, that occurs almost exclusively in females, induces extensive lymphocyte accumulation in lacrimal and salivary glands, and represents one of the leading causes of dry eye and mouth in the world. The purpose of this study was to determine whether the profound, gender-related differences observed in the magnitude of exocrine gland inflammation in Sj?gren's syndrome may also be found in tissues of mouse models of this disorder. Lacrimal and submandibular glands were obtained from adult MRL/lpr, MRL+/+ (MRL+), NZB/NZW F1 (F1), C3H/lpr, C3H/gld (gld), C57BL/6-lpr/lpr [B6/lpr; with (bcl-2(+)/lpr) or without (bcl-2(-)/lpr) bcl-2 transgene insertion] and nonobese diabetic (NOD) mice after the onset of autoimmune disease, and processed for microscopy and image analysis. Our results showed that: (1) the extent of inflammation was significantly greater in lacrimal glands of female MRL/lpr, MRL+, F1, C3H/lpr and gld mice, and salivary glands of female MRL+, F1 and gld mice, relative to those of males; (2) the severity of inflammation in NOD mice showed a tissue-specific pattern: inflammation was far worse in lacrimal glands of males, whereas immune pathology was far greater in salivary tissues in females; and (3) no gender-related variations were present in the degree of inflammation in lacrimal glands of bcl-2(+)/lpr and bcl-2(-)/lpr mice or in submandibular tissues of MRL/lpr, C3H/lpr, bcl-2(+)/lpr and bcl-2(-)/lpr mice. Our findings demonstrate that gender-, strain- and tissue-related differences exist in the extent of inflammation in several mouse models of Sj?gren's syndrome.  相似文献   
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