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1.
Mature T cells residing in peripheral lymphoid organs have frequent contact with antigen presenting cells (APC). Such contact may be required for T cell survival, but the degree to which signals in mature T cells are induced by TCR recognition of self peptide/MHC complexes is unclear. We have used induction of the early growth response gene 1 (Egr1) as an indicator of signal transduction in 3.L2 (I-Ek-restricted) T cells interacting with APC in the absence of exogenous antigen. The data show that Egr1 can be induced in 3.L2 T cells by TCR recognition of self peptides presented by I-Ek. However, a more transient induction of Egr1 can be induced in 3.L2 T cells interacting with dendritic cells derived from class II/beta2m double-deficient mice. Egr1 induction after T cell-APC contact was also observed in a freshly isolated polyclonal CD4 T cell population. The data suggest that self peptide/MHC recognition by the TCR induces a signal in T cells and that dendritic cells can also induce a more transient T cell signal by an MHC-independent mechanism.  相似文献   
2.
Radiation therapy plays an integral part in managing intracranial tumors. While the risk:benefit ratio is considered acceptable for treating malignant tumors, risks of long-term complications of radiotherapy need thorough assessment in adults treated for benign tumors. Many previously reported delayed complications of radiotherapy can be attributed to inappropriate treatment or to the sensitivity of a developing child's brain to radiation. Medical records, radiological studies, autopsy findings, and follow-up information were reviewed for 58 adult patients (31 men and 27 women) treated between 1958 and 1987 with radiotherapy for benign intracranial tumors. Patient ages at the time of irradiation ranged from 21 to 87 years (mean 47.7 years). The pathology included 46 pituitary adenomas, five meningiomas, four glomus jugulare tumors, two pineal area tumors, and one craniopharyngioma. Average radiation dosage was 4984 cGy (range 3100 to 7012 cGy), given in an average of 27.2 fractions (range 15 to 45 fractions), over a period averaging 46.6 days. The follow-up period ranged from 3 to 31 years (mean 8.1 years). Findings related to tumor recurrence or surgery were excluded. Twenty-two patients had complications considered to be delayed side effects of radiotherapy. Two patients had visual deterioration developing 3 and 6 years after treatment; six had pituitary dysfunction; and 17 had varying degrees of parenchymal changes of the brain, occurring mostly in the temporal lobes and relating to the frequent presentation of pituitary tumors (two of these also had pituitary dysfunction). One clival tumor with the radiographic appearance of a meningioma, developed 30 years post-irradiation for acromegaly. This study unveils considerable delayed sequelae of radiotherapy in a series of adult patients receiving what is considered "safe" treatment for benign brain tumors.  相似文献   
3.
OBJECTIVE: Alcohol use disorders (defined as DSM-IV alcohol dependence or abuse) are prevalent and serious problems among adolescents. As adolescence is marked by progressive hippocampal development, this brain region may be particularly susceptible to the adverse effects of adolescent alcohol use disorders. This study compared the hippocampal volumes of adolescents and young adults with adolescent-onset alcohol use disorders to those of healthy matched comparison subjects. METHOD: Magnetic resonance imaging was used to measure the hippocampal volumes and volumes of comparison brain regions in 12 subjects with alcohol use disorders and 24 comparison subjects matched on age, sex, and handedness. RESULTS: Both left and right hippocampal volumes were significantly smaller in subjects with alcohol use disorders than in comparison subjects. Total hippocampal volume correlated positively with the age at onset and negatively with the duration of the alcohol use disorder. Intracranial, cerebral, and cortical gray and white matter volumes and measures of the mid-sagittal area of the corpus callosum did not differ between groups. CONCLUSIONS: In the mature brain, chronic alcohol use disorders are associated with graded global brain dysmorphology. Although the etiology, neuropsychological consequences, and permanence of these hippocampal findings need to be further examined, these findings suggest that, during adolescence, the hippocampus may be particularly susceptible to the adverse effects of alcohol.  相似文献   
4.
In 2010, Coxiella burnetii was identified at a high prevalence in the placentas of Northern fur seals (Callorhinus ursinus) collected at a single rookery on St. Paul Island Alaska; an area of the United States where the agent was not known to be present. As contamination was hypothesized as a potential cause of false positives, but nothing was known about environmental C. burnetii in the region, an environmental survey was conducted to look for the prevalence and distribution of the organism on the island. While environmental prevalence was low, two strains of the organism were identified using PCR targeting the COM1 and IS1111 genes. The two strains are consistent with the organism that has been increasingly identified in marine mammals as well as a strain type more commonly found in terrestrial environments and associated with disease in humans and terrestrial animals. Further work is needed to elucidate information regarding the ecology of this organism in this region, particularly in association with the coastal environment.  相似文献   
5.
Neisseria gonorrhoeae quickly develops drug resistance. Time-kill curves revealed that EDTA and TOL-463 inhibit growth similar to penicillin, ciprofloxacin, and azithromycin. Furthermore, synergistic and additive antimicrobial interactions occurred when EDTA and TOL-463 were combined with penicillin or azithromycin, respectively, suggesting that further investigations into these unconventional antimicrobials may be advantageous.  相似文献   
6.
BackgroundAlpha-gal syndrome (AGS) is an emerging immunoglobulin E (IgE)–mediated allergy to galactose-alpha-1,3-galactose (alpha-gal). The geographic distribution and burden of AGS in the United States are unknown.ObjectiveTo characterize alpha-gal IgE testing patterns and describe the trends and distribution from 2010 to 2018 in the United States.MethodsThis retrospective analysis included all persons tested for alpha-gal IgE antibodies by Viracor-IBT Laboratories (Lee’s Summit, Missouri), the primary site of testing in the United States. Data included age and sex of person tested, specimen state of origin, collection date, and result value; persons with at least 1 positive test result (≥0.1 kU/L) were compared with negatives. Proportions tested and with positive test results were calculated using the US Census population estimates.ResultsOverall, 122,068 specimens from 105,674 persons were tested for alpha-gal IgE during July 1, 2010, to December 31, 2018. Nearly one-third (34,256, 32.4%) had at least 1 positive result. The number of persons receiving positive test results increased 6-fold from 1110 in 2011 to 7798 in 2018. Of those receiving positive test results, mean [SD] age was 46.9 (19.8) years; men were more likely to test positive than women (43.3% vs 26.0%). Arkansas, Virginia, Kentucky, Oklahoma, and Missouri had the highest number of persons who were tested and had a positive result per 100,000 population.ConclusionMore than 34,000 persons, most presumably symptomatic, have received positive test results for IgE antibodies to alpha-gal, suggesting AGS is an increasingly recognized public health problem. The geographic distribution of persons who tested positive is consistent with exposure to Amblyomma americanum ticks.  相似文献   
7.
Abstract Vaginal bacterial communities play an important role in human health and have been shown to influence HIV infection. Pigtailed macaques (Macaca nemestrina) are used as an animal model of HIV vaginal infection of women. Since the bacterial microbiota could influence retrovirus infection of pigtailed macaques, the genital microbiota in 10 cycling macaques was determined by pyrosequencing. The microbiota of all macaques was polymicrobial with a median of 13 distinct genera. Strikingly, the genera Sneathia and Fusobacterium, both in the phylum Fusobacteria, accounted for 18.9% and 13.3% of sequences while the next most frequent were Prevotella (5.6%), Porphyromonas (4.1%), Atopobium (3.6%), and Parvimonas (2.6%). Sequences corresponding to Lactobacillus comprised only 2.2% of sequences on average and were essentially all L. amylovorus. Longitudinal sampling of the 10 macaques over an 8-week period, which spanned at least one full ovulatory cycle, showed a generally stable presence of the major types of bacteria with some exceptions. These studies show that the microbiota of the pigtailed macaques is substantially dissimilar to that found in most healthy humans, where the genital microbiota is usually dominated by Lactobacillus sp. The polymicrobial makeup of the macaque bacterial populations, the paucity of lactobacilli, and the specific types of bacteria present suggest that the pigtailed macaque microbiota could influence vaginal retrovirus infection.  相似文献   
8.

Methods

Nineteen cases of extension contracture were operated upon by modified technique of Judet quadricepsplasty, one female and eighteen males. Results were evaluated by HSSKF score as well as Judet criteria.

Purpose

The hypothesis is that recurrence of adhesions underneath the quadriceps leads to loss of some of the gained intraoperative flexion range.

Results

In this series, flexion range deteriorates but this was found to be statistically non significant on the functional score of the patients.  相似文献   
9.
Definitive radiotherapy for early glottic carcinoma continues to offer excellent control and the advantage of voice preservation. In the 13 years from January 1972 through December 1984, there were 187 patients diagnosed with squamous cell carcinoma of the glottis at the University of Virginia Medical Center. One hundred forty-eight patients were treated with definitive radiotherapy as the initial management. The 3-year disease-free survival for the irradiated population was 93.6% in stage I and 75.5% in stage II. Twenty patients had recurrences following radiotherapy, and 13 of 20 were successfully surgically salvaged for an overall determinate survival of 100% in stage I and 85.7% in stage II at 3 years. These statistics are comparable to those from our previous 16-year review of 147 patients from 1956 through 1971. Factors of prognostic significance were persistent hoarseness after radiotherapy, impaired cord mobility, subglottic extension, and multiple sites of involvement in stage I. We conclude that definitive radiotherapy offers excellent survival and that a majority of the small number of treatment failures can be managed with surgical salvage.  相似文献   
10.
Persistent or recurrent disease following surgery and chemotherapy in ovarian carcinoma remains a major therapeutic dilemma. Between January 1980 and December 1985, there were 26 patients who had previously undergone cytoreductive surgery and chemotherapy and were treated with external beam radiotherapy. Twenty-one of these patients had been treated with platinum-adriamycin-cytoxan (PAC) regimen and 5 were treated with other combinations. Surgical reevaluation was performed in 21 of the 26 patients and only 4/21 (19%) patients were free of disease. All 26 patients were irradiated with a planned dose of 2500 cGy/100 cGy/day or 2280 cGy/120 cGy/day to the whole abdomen and a final calculated dose to the pelvis of 4500 cGy. Initial evaluation showed a 3-year actuarial survival rate of 51% and a disease-free survival rate of 42%. Follow-up analysis yields survivals of 45 and 35%, respectively. Severe gastrointestinal complications were observed in 3/26 patients and all hematologic complications resolved. Variables of prognostic significance were chemotherapy tolerance, grade, and volume of residual disease. We conclude that a proportion of patients with disease following cytoreductive surgery and chemotherapy may be salvaged with abdominopelvic irradiation.  相似文献   
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