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71.
72.
Chemokines are chemotactic cytokines that are mainly involved in the migratory patterns of immune cells. Few studies have evaluated the levels of chemokines in children with acute bacterial infections. The aim of this study was to evaluate the serum levels of chemokines MCP‐1, RANTES, MIG and IP‐10 in children with sepsis, community‐acquired pneumonia (CAP) and skin abscess. Serum levels of MCP‐1, RANTES, MIG and IP‐10 were measured in 37 children with sepsis, 27 children with CAP, 25 children with skin abscess and 20 controls with no signs of infection. Patients with sepsis, CAP and skin abscess had higher concentrations of RANTES compared to controls (= 0.0057, = 0.0004 and = 0.0108, respectively). IP‐10 values were higher in patients with sepsis compared to children with skin abscess (= 0.0075). However, MCP‐1 levels were lower in septic patients compared to controls (= 0.0136). There was no difference on MIG concentrations between the groups. Our original findings observed that RANTES was consistently elevated in all types of infections suggesting this chemokine may play an important role in the pathogenesis of bacterial infection. Additionally, patients with sepsis had a unique pattern of response with high levels of IP‐10 but low levels of MCP‐1, which should be further explored as the markers of disease severity.  相似文献   
73.

Background  

The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls.  相似文献   
74.
Resistant hypertension (RHT) is associated with obstructive sleep apnea (OSA) and increased aortic stiffness, measured by carotid‐femoral pulse wave velocity (cf‐PWV). We aimed to evaluate in a randomized controlled trial, the effect of Continuous positive airway pressure (CPAP) treatment on cf‐PWV in comparison with a control group in patients with RHT and moderate‐severe OSA. One‐hundred and sixteen patients were randomized to 6‐month CPAP treatment (56 patients) or no therapy (60 patients), while keeping their antihypertensive treatment unchanged. Carotid‐femoral pulse wave velocity was performed at the beginning and end of the 6‐month period. Intention‐to‐treat intergroup differences in cf‐PWV changes were assessed by a generalized mixed‐effects model with the allocation group as a fixed factor and adjusted for age, sex, changes in mean arterial pressure and the baseline cf‐PWV values. Subgroup sensitivity analyses were performed, excluding patients with low CPAP adherence and low cf‐PWV at baseline. CPAP and control groups had similar clinic‐laboratorial characteristics. Patients had a mean cf‐PWV of 9.4 ± 1.6 m/s and 33% presented cf‐PWV > 10 m/s. During treatment, the control group had a mean increase in cf‐PWV of +0.43 m/s (95% confidence interval [CI], +0.14 to +0.73 m/s; p = .005), whereas the CPAP group had a mean increase of +0.03 m/s (95% CI, ?0.33 to +0.39 m/s; p = .87), resulting in a mean difference in changes between CPAP and control of ?0.40 m/s (95% CI, ?0.82 to +0.02 m/s; p = .059). Subgroup analyses did not change the results. In conclusion, a 6‐month CPAP treatment did not reduce aortic stiffness, measured by cf‐PWV, in patients with RHT and moderate/severe OSA, but treatment may prevent its progression, in contrast to no‐CPAP therapy.  相似文献   
75.
Current induced in cultured cerebellar granule cells by the bath application of kainate (500 μM) was measured using the conventional patch-clamp technique. Two different kinds of responses were observed after the agonits perfusion. Some cells exhibited small inward whole-cell currents: 116±40 pA (7 cells) at a clamp potential of−60 mV; in other cells, the agonist induced significantly larger currents: 420±35 pA (6 cells) at a clamp potential of −60 mV. The current flowing in the agonist-activated ionic channels was indirectly estimated by processing the fluctuations of whole-cell current by means of an original parametric method. Mean conductance of the underlying channels was then determined from the single-channel current estimated at different clamp potentials. In the cells exhibiting small inward currents, the mean conductance was equal to 0.5±0.2 pS (7 cells), whereas in the cells with large inward currents it was 3±0.4 pS (6 cells). This result gives a coherent explanation of the different kinds of responses observed at macroscopic level in the whole-cell current and confirms that kainate-activated channels can exhibit different levels of conductance.  相似文献   
76.

Background

Access to pediatric antiretroviral formulations is increasing in resource-limited countries, however adult FDCs are still commonly used by antiretroviral therapy (ART) programs.

Objective

To describe long-term effectiveness of using adult FDC of d4T+3TC+NVP (Triomune) in children for HIV treatment.

Methods

Clinical, immunologic, and virologic outcomes of HIV-infected ART-naïve children aged six months to 12 years, were evaluated up to 96 weeks post-ART initiation.

Results

From March 2004 to June 2006, 104 children were followed with a median age of 5.4 years, median CD4 cell percent and HIV-1 RNA were 11.0% (IQR 6.7–13.9) and 348,846copies/mL (IQR 160,941–681,313) respectively at baseline. Using Kaplan-Meir estimates, 75% of children had undetectable viral loads (<400copies/mL) at 96weeks of ART. Children with a baseline CD4 cell percent >15% were 3 times more likely to achieve viral load <400copies/mL than those with baseline CD4 cell percent <5% after adjusting for baseline age {aHR = 3.03 (1.10–8.32), p=0.03}; no difference was found among those with CD4 cell percent >5–14.9% and <5%.

Conclusion

Treatment with generic adult FDC for HIV-infected Ugandan children led to sustained clinical, immunologic and virologic response during 96 weeks of ART. Early initiation of ART is key to achieving virological success.  相似文献   
77.
Cervical cancer is a major source of illness and death among women worldwide and genital infection with oncogenic human papillomavirus (HPV) its principal cause. There is evidence of the influence of the male factor in the development of cervical neoplasia. Nevertheless, the pathogenic processes of HPV in men are still poorly understood. It has been observed that different HPV types can be found among couples. The objective of the present study was to investigate HPV infections in female patients (n = 60 females/group) as well as in their sexual partners and to identify the concordance of HPV genotypes among them. By using the polymerase chain reaction, we detected a 95% prevalence of HPV DNA in women with cervical intraepithelial neoplasia (CIN) compared to 18.3% in women with normal cervical epithelium, with a statistically significant difference (P < 0.001). The HPV DNA prevalence was 50% in male partners of women with CIN and 16.6% in partners of healthy women. In the control group (healthy women), only 9 couples were simultaneously infected with HPV, and only 22.2% of them had the same virus type, showing a weak agreement rate (kappa index = 0.2). Finally, we observed that HPV DNA was present in both partners in 30 couples if the women had CIN, and among them, 53.3% shared the same HPV type, showing moderate agreement, with a kappa index of 0.5. This finding supports the idea of circulation and recirculation of HPV among couples, perpetuating HPV in the sexually active population, rather than true recurrences of latent infections.  相似文献   
78.
79.
80.
The influence of the arterial baroreflex on the heart rate variability is analysed by using a mathematical model of heart rate baroreceptor control. The basic mechanisms of the model, sufficient to elicit heart rate variability include: systemic circulation, a non-pulsatile cardiac pump and nonlinear negative feedback simulating arterial baroreflex closed-loop control of the heart rate (−3bpm/mmHg as maximum reflex sensitivity). The latter reproduces, through two distinct delayed branches (0.8 and 2.8 s), the short-term autonomic control effected respectively by sympathetic and parasympathetic divisions on the sinus node. By means of this model, two distinct self-sustained oscillatory components with incommensurate frequencies (0.1 and 0.26 Hz) are reproduced. Frequencies of these two oscillatory components closely agree with the main heart rate rhythms in humans (0.09±0.01 Hz and 0.26±0.01 Hz). When sympathetic-mediated regulation prevails over parasympathetic activity, simulated heart rate oscillation is characterised by a low frequency (∼0.1 Hz). On the other hand, a high-frequency oscillatory component (∼0.26 Hz) appears when enhanced vagal activation or partial inhibition of the sympathetic control is simulated. When both autonomic divisions are operative, both low- and high-frequency components are present and the heart rate oscillates quasi-periodically. This variability in heart rate at different frequencies is reproduced without including outside perturbations and is due to the nonlinear delayed structure of the closed-loop control. Bifurcation theory of nonlinear system is used to explain the high sensitivity of the heart rate oscillatory pattern to model parameter changes.  相似文献   
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