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991.
Several lines of evidence have suggested that renal handling of proteins in rats with several nephropathies may contribute to the tubulointerstitial damage observed in these animals. It has been suggested that proteins filtered by the glomeruli may be toxic for tubule cells. The aim of this study was to investigate the relationship between albuminuria and tubular lesions observed in rats during the first two weeks after treatment with adriamycin (AD). Thirty female Wistar rats were injected intravenously with adriamycin at the dose of 3.5 (17 rats) or 5mg/kg body weight (13 rats), and 7 were injected with 0.15 M NaCl (control group). Seven days later, we replaced drinking water with a 0.10 M sodium bicarbonate solution for 6 of the animals injected with 5 mg/kg adriamycin (group AD-B). Urine samples were collected before and 7 and 15 days after treatment to quantify albumin. The rats were killed 7 and 18 days after the injections, and the kidneys removed for immunohistochemical study. We observed a significant increase in urinary albumin excretion 15 days after AD injection (3.5 mg/kg), but not 7 days after AD. However, in the animals injected with 5.0 mg/kg AD (group AD-5) the increase in albuminuria was observed as early as on day 7. The immunohistochemical studies showed increased vimentin and albumin immunoreaction in the tubular cells of the renal cortex from the kidneys of rats injected with 3.5 mg/kg (group AD-3) only 18 days after treatment (p < 0.05), whereas in the animals treated with 5 mg/kg AD these immunohistochemical alterations were more intense. However, treatment with sodium bicarbonate attenuated the tubular lesions and reduced albumin reabsorption in adriamycin-treated rats. In conclusion, these experiments showed a relationship between albuminuria and tubular lesions in adriamycin-treated rats.  相似文献   
992.
993.
Inflammation of the subarachnoid and ventricular space contributes to the development of brain damage i.e. cortical necrosis and hippocampal apoptosis in pneumococcal meningitis (PM). Galectin-3 and -9 are known pro-inflammatory mediators and regulators of apoptosis. Here, the gene and protein expression profile for both galectins was assessed in the disease progression of PM. The mRNA of Lgals3 and Lgals9 increased continuously in the cortex and in the hippocampus from 22 h to 44 h after infection. At 44 h after infection, mRNA levels of Lgals9 in the hippocampus were 7-fold and those of Lgals3 were 30-fold higher than in uninfected controls (P<0.01). Galectin-9 protein did not change, but galectin-3 significantly increased in cortex and hippocampus with the duration of PM. Galectin-3 was localized to polymorphonuclear neutrophils, microglia, monocytes and macrophages, suggesting an involvement of galectin-3 in the neuroinflammatory processes leading to brain damage in PM.  相似文献   
994.
Deree J  de Campos T  Shenvi E  Loomis WH  Hoyt DB  Coimbra R 《The Journal of trauma》2007,62(4):818-27; discussion 827-8
BACKGROUND: We have previously demonstrated that postshock resuscitation with Hypertonic saline and Pentoxifylline (HSPTX) attenuates pulmonary and histologic gut injury when compared with Ringer's lactate (RL). In this study, we hypothesized that the decrease in gut injury observed with HSPTX is associated with the attenuation of inducible nitric oxide synthase (iNOS) activity and production of ileal proinflammatory mediators after hemorrhagic shock. METHODS: In a rat model of hemorrhagic shock, resuscitation was conducted with RL (32 mL/kg; n = 7) or HSPTX (4 mL/kg 7.5% NaCl + PTX 25 mg/kg; n = 7). Sham animals that did not undergo shock were also studied. Four hours after resuscitation, the terminal ileum was collected for evaluation of nitrite, tumor necrosis factor (TNF)-alpha, Interleukin (IL)-6, and cytokine-induced neutrophil chemoattractant (CINC) by enzyme immunoassay. Heme oxygenase-1 (HO-1), iNOS, cytoplasmic inhibitor of kappa B (Ikappa B) phosphorylation, and nuclear factor (NF)kappa B p65 nuclear translocation were determined by Western blot. RESULTS: HSPTX resuscitation resulted in a 49% decrease in iNOS when compared with RL (p < 0.05). Similar results were obtained when examining nitrite (882 +/- 59 vs. 1,435 +/- 177 micromol/L; p < 0.01), and HO-1 content (p < 0.05). RL resuscitation resulted in markedly higher levels of TNF-alpha (83 +/- 27 vs. 9 +/- 5 pg/mL; p < 0.01), IL-6 (329 +/- 58 vs. 118 +/- 43 pg/mL; p < 0.05), and CINC (0.43 +/- .06 vs. 0.19 +/- .08 ng/mL; p < 0.05) than HSPTX. The increase in cytokines observed with RL was also associated with an increase in I-kappaB phosphorylation (p < 0.01) and NF-kappaB p65 nuclear translocation (p < 0.001). CONCLUSION: The attenuation in gut injury after postshock resuscitation with HSPTX is associated with downregulation of iNOS activity and subsequent proinflammatory mediator synthesis. HSPTX has the potential to be a superior resuscitation fluid with significant immunomodulatory properties.  相似文献   
995.
Holbrook TL  Hoyt DB  Coimbra R  Potenza B  Sise MJ  Sack DI  Anderson JP 《The Journal of trauma》2007,62(3):577-83; discussion 583
BACKGROUND: Injury is a leading cause of death and preventable morbidity in adolescents. Little is known about long-term quality of life (QoL) outcomes in injured adolescents. The objectives of the present report are to describe long-term QoL outcomes and compare posttrauma QoL to national norms for QoL in uninjured adolescents from the National Health Interview Survey (NHIS). METHODS: In all, 401 trauma patients aged 12 to 19 years were enrolled in the study. Enrollment criteria excluded spinal cord injury. QoL after trauma was measured using the Quality of Well-being (QWB) scale, a sensitive and well-validated functional index (range: 0 = death to 1.000 = optimum functioning). Patient outcomes were assessed at discharge, and 3, 6, 12, 18, and 24 months after discharge. NHIS data were based on 3 survey years and represent a population-based U.S. national random sample of uninjured adolescents. RESULTS: Major trauma in adolescents was associated with significant and marked deficits in QoL throughout the 24-month follow-up period, compared with NHIS norms for this age group. Compared with NHIS norms for QoL in uninjured adolescents aged 12 to 19 years (N = 81,216,835; QWB mean = 0.876), injured adolescents after major trauma had striking and significant QoL deficits beginning at 3-month follow-up (QWB mean = 0.694, p < 0.0001), that continued throughout the long-term follow-up 24 months after discharge (6-month follow-up QWB mean = 0.726, p < 0.0001; 12-month follow-up QWB mean = 0.747, p < 0.0001; 18-month follow-up QWB mean = 0.758, p < 0.0001; 24-month follow-up QWB mean = 0.766, p < 0.0001). QoL deficits were also strongly associated with age (>or=15 years) and female sex. Other significant risk factors for poor QoL outcomes were perceived threat to life, pedestrian struck mechanism, and Injury Severity Scores >16. CONCLUSIONS: Major trauma in adolescents is associated with significant and marked deficits in long-term QoL outcomes, compared with U.S. norms for healthy adolescents. Early identification and treatment of risk factors for poor long-term QoL outcomes must become an integral component of trauma care in mature trauma care systems.  相似文献   
996.
The present study was carried out in Wistar rats, using the jaw-opening reflex and dental pulp stimulation, to investigate noradrenaline- and serotonin-mediated antinociceptive circuits. The effects of microinjections of bradykinin into the principal sensory trigeminal nucleus (PSTN) before and after neurochemical lesions of the locus coeruleus noradrenergic neurons were studied. Neuroanatomical experiments showed evidence for reciprocal neuronal pathways connecting the locus coeruleus (LC) to trigeminal sensory nuclei and linking monoaminergic nuclei of the pain inhibitory system to spinal trigeminal nucleus (STN). Fast blue (FB) injections in the locus coeruleus/subcoeruleus region retrogradely labeled neurons in the contralateral PSTN and LC. Microinjections of FB into the STN showed neurons labeled in both ipsilateral and contralateral LC, as well as in the ipsilateral Barrington's nucleus and subcoeruleus area. Retrograde tract-tracing with FB also showed that the mesencephalic trigeminal nucleus sends neural pathways towards the ipsilateral PSTN, with outputs from cranial and caudal aspects of the brainstem. In addition, neurons from the lateral and dorsolateral columns of periaqueductal gray matter also send outputs to the ipsilateral PSTN. Microinjections of FB in the interpolar and caudal divisions of the STN labeled neurons in the caudal subdivision of STN. Microinjections in the STN interpolar and caudal divisions also retrogradely labeled serotonin- and noradrenaline-containing nucleus of the brainstem pain inhibitory system. Finally, the gigantocellularis complex (nucleus reticularis gigantocellularis/paragigantocellularis), nucleus raphe magnus and nucleus raphe pallidus also projected to the caudal divisions of the STN. Microinjections of bradykinin in the PSTN caused a statistically significant long-lasting antinociception, antagonized by the damage of locus coeruleus-noradrenergic neuronal fibres with (N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine) (DSP4), a neurotoxin that specifically depleted noradrenaline from locus coeruleus terminal fields. These data suggest that serotonin- and noradrenaline-containing nuclei of the endogenous pain inhibitory system exert a key-role in the antinociceptive mechanisms of bradykinin and the locus coeruleus is crucially involved in this effect.  相似文献   
997.

OBJETIVE:

This study evaluated retroperitoneal hematomas produced by bilateral injury of iliac arteries (uncontrolled hemorrhage), blood volume loss, transcapillary refill, the effects of volume replacement on retroperitoneal bleeding and the hemodynamic changes with and without treatment.

METHODS:

Initial blood volume was determined with Tc99m-labelled red cells, and bleeding was evaluated by means of a portable scintillation camera positioned over the abdomen. Previously splenectomized mongrel dogs (16.8 ± 2.2 kg) were submitted to hemorrhage for 30 minutes and randomized into three groups: I - no treatment (n=7); II - treatment with 32 mL/kg of Lactated Ringer’s for three to five minutes (n=7); and III - treatment with 4 mL/kg of 7.5% NaCl plus 6.0% dextran 70 for three to five minutes (n=7). They were studied for an additional 45 minutes.

RESULTS:

Volume replacement produced transitory recovery in hemodynamic variables, including mean pulmonary artery pressure, pulmonary capillary wedge pressure and cardiac index, with significant increase in dogs treated with 32 mL/kg of Lactated Ringer’s and 7.5% NaCl plus 6.0% dextran 70 (p<0.001, against no treatment), along with a decrease (p<0.001) in the systemic vascular resistance index. Groups II and III had significant initial decreases in hematocrit and hemoglobin. The treated dogs (groups II and III) presented rebleeding, which was greater during treatment with 32 mL/kg of Lactated Ringer’s (group II).

CONCLUSIONS:

Despite the rebleeding observed in treated groups, the utilization of hypertonic saline solution with dextran proved to be effective in the initial reanimation, producing evident transcapillary refill, while the Lactated Ringer’s solution produced capillary extravasation and was ineffective in the initial volume replacement in this model of uncontrolled hemorrhage.  相似文献   
998.
999.
Psoriasis is a chronic, recurrent inflammatory cutaneous disease. Psoriasis patients alternate between periods of remission and periods of exacerbation of the disease. Usually, psoriasis severity is clinically evaluated using tools like Psoriasis Area and Severity Index that present some limitations and subjectivity. Clinicians select the therapy according to psoriasis severity, aiming that patients achieve longer remission periods and improve their quality of life. Biological markers for diagnosis and prognosis of psoriasis help to establish its severity and to monitor the therapeutic response; moreover, biomarkers of psoriasis assist clinicians in their therapeutic decision to treat psoriasis and to choose earlier and more adequate therapeutic strategies, avoiding or minimising worsening of psoriasis. With these markers, they would be able to monitor therapeutics, avoiding unnecessary therapeutic surcharge or changes to a more aggressive therapy. As any attempt to identify these biomarkers should be encouraged, in this review, we will debate published data concerning the proposal of biomarkers to evaluate severity and response to treatment of psoriasis vulgaris.  相似文献   
1000.

Background

The aim of this study was to compare sociodemographic characteristics, patterns of drug use, and risky sexual behaviour among female and male users of crack cocaine.

Methods

Between 2012 and 2013, we conducted a cross-sectional study of 919 crack cocaine users (783 men and 136 women) in Central Brazil using face-to-face interviews. Blood samples were collected to test for syphilis. The Chi-Square Automatic Interaction Detector (CHAID) was used to explore the differences between genders. We implemented two models: the first model included previous incarceration and variables related to patterns of drug use, and the second model included variables related to sexual risky behaviours and syphilis exposure.

Results

Women consumed more crack cocaine than men on a regular basis; however, poly-drug use was more common among men. More women than men reported exchanging sex for money and/or drugs and inconsistent condom use during sexual intercourse; women also reported more sexual partners. In addition, the frequency of sexual violence was higher for women than men. A higher proportion of women than men were positive for syphilis (27.2% vs. 9.2%; p?<?0.001). The CHAID decision tree analysis identified seven variables that differentiated the genders: previous incarceration, marijuana use, daily crack cocaine consumption, age at first illicit drug use, sexual violence, exchange of sex for money and/or drugs, and syphilis exposure.

Conclusion

Our findings demonstrate a difference in patterns of crack cocaine consumption and sexual risky behaviours between genders, thus indicating a need for gender-specific interventions in this population.
  相似文献   
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