Diagnosis and treatment of tuberculous pleural effusion in 2006

Tuberculous (TB) pleural effusion occurs in approximately 5% of patients with Mycobacterium tuberculosis infection. The HIV pandemic has been associated with a doubling of the incidence of extrapulmonary TB, which has resulted in increased recognition of TB pleural effusions even in developed nations. Recent studies have provided insights into the immunopathogenesis of pleural TB, including memory T-cell homing and chemokine activation. The definitive diagnosis of TB pleural effusions depends on the demonstration of acid-fast bacilli in the sputum, pleural fluid, or pleural biopsy specimens. The diagnosis can be established in a majority of patients from the clinical features, pleural fluid examination, including cytology, biochemistry, and bacteriology, and pleural biopsy. Measurement of adenosine deaminase and interferon-gamma in the pleural fluid and polymerase chain reaction for M tuberculosis has gained wide acceptance in the diagnosis of TB pleural effusions. Although promising, these tests require further evaluation before their routine use can be recommended. The treatment of TB pleural effusions in patients with HIV/AIDS is essentially similar to that in HIV-negative patients. At present, evidence regarding the use of corticosteroids in the treatment of TB pleural effusion is not clear-cut.     

The potential of a 2Tone Trainer to help patients use their metered-dose inhalers

BACKGROUND: Many patients have problems using the correct inhalation technique when they use their metered-dose inhalers (MDIs). We have investigated whether a training aid (2Tone Trainer [2T]; Canday Medical Ltd; Newmarket, UK) helps to maintain the correct inhaler technique after patients leave the clinic METHODS: Ethics committee approval was obtained, and patients gave consent. Asthmatic patients who had been prescribed an MDI had their inhalation technique assessed. Their peak inhalation flow (PIF) when using their MDI, FEV(1), and the Juniper asthma quality of life questionnaire (AQLQ) score were measured. Those patients using the recommended MDI technique were the good-technique (GT) group. The remainder were randomized to receive verbal training (VT) or VT plus the 2T to improve their MDI technique. All patients returned 6 weeks later. RESULTS: There were 36, 35, and 36 asthmatic patients, respectively, who completed the GT, VT, and 2T procedures. FEV1 did not change within all groups between visit 1 and 2. PIF and AQLQ score did not change in the GT group. In the VT and 2T groups, the AQLQ score increased by mean differences of 0.33 (95% confidence interval [CI], 0.14 to 0.53; p < 0.001) and 0.74 (95% CI, 0.62 to 0.86; p < 0.001). At visit 1, all patients in the VT and 2T groups inhaled > 90 L/min decreasing to 12 patients and 1 patient, respectively, at visit 2 (p < 0.001 both groups). The overall changes in the 2T group for PIF and AQLQ score, between visits 1 and 2, were significantly (p < 0.001) greater than the corresponding changes in the VT group. CONCLUSION: The 2T helps patients to maintain the recommended MDI technique posttraining with improvements in AQLQ score.     

Etiology of community-acquired pneumonia in hospitalized patients in chile: the increasing prevalence of respiratory viruses among classic pathogens

BACKGROUND AND STUDY OBJECTIVES: The range and relative impact of microbial pathogens, particularly viral pathogens, as a cause of community-acquired pneumonia (CAP) in hospitalized adults has not received much attention. The aim of this study was to determine the microbial etiology of CAP in adults and to identify the risk factors for various specific pathogens. METHODS: We prospectively studied 176 patients (mean [+/- SD] age, 65.8 +/- 18.5 years) who had hospitalized for CAP to identify the microbial etiology. For each patient, sputum and blood cultures were obtained as well as serology testing for Mycoplasma pneumoniae and Chlamydophila pneumoniae, urinary antigen testing for Legionella pneumophila and Streptococcus pneumoniae, and a nasopharyngeal swab for seven respiratory viruses. RESULTS: Microbial etiology was determined in 98 patients (55%). S pneumoniae (49 of 98 patients; 50%) and respiratory viruses (32%) were the most frequently isolated pathogen groups. Pneumococcal pneumonia was associated with tobacco smoking of > 10 pack-years (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.2 to 5.4; p = 0.01). Respiratory viruses were isolated more often in fall or winter (28%; p = 0.011), and as an exclusive etiology tended to be isolated in patients >/= 65 years of age (20%; p = 0.07). Viral CAP was associated with antimicrobial therapy prior to hospital admission (OR, 4.5; 95% CI, 1.4 to 14.6). CONCLUSIONS: S pneumoniae remains the most frequent pathogen in adults with CAP and should be covered with empirical antimicrobial treatment. Viruses were the second most common etiologic agent and should be tested for, especially in fall or winter, both in young and elderly patients who are hospitalized with CAP.     

Effects of nocturnal noninvasive mechanical ventilation on heart rate variability of patients with advanced COPD

BACKGROUND: Cardiovascular comorbidities have a negative impact on the health status and prognosis of patients with COPD. We determined whether nocturnal noninvasive (positive) mechanical ventilation (NIMV) can improve heart rate variability (HRV), decrease circulating natriuretic peptide levels, and improve functional performance of patients with very advanced COPD. METHODS: A randomized, double-blind, parallel controlled trial was conducted in 23 participants with stable but advanced COPD. Participants received standard medical therapy plus nocturnal NIMV or standard medical therapy plus sham NIMV for 3 months. RESULTS: After 3 months of NIMV therapy, the 24-h triangular interpolation of N-N intervals increased from 322 to 473 ms (p = 0.034), the 24-h HRV index (HRVI) increased from 21.8 to 29.9 ms (p = 0.035), nocturnal HRVI increased from 6.1 to 8.0 ms (p = 0.026), and the SD of the average N-N interval increased from 37 to 41 ms (p = 0.020). None of these indexes changed significantly in the control group. Additionally, compared with the control group, the pro-atrial natriuretic peptide levels declined significantly in the NIMV group (p = 0.013). CONCLUSIONS: NIMV applied nocturnally over 3 months may improve HRV, reduce circulating natriuretic peptide levels, and enhance the functional performance of patients with advanced but stable COPD. While not definitive due to small sample size, these data suggest that nocturnal NIMV may reduce the impact of cardiac comorbidities in COPD patients.     

AST-120, an oral adsorbent, delays the initiation of dialysis in patients with chronic kidney diseases

The effects of an oral adsorbent, AST-120, in chronic kidney disease (CKD) patients was evaluated by the 24-month dialysis-free rate and 50% dialysis-free period. This study retrospectively analyzed 193 patients admitted to the Osaka Medical College Hospital between January 1994 and December 2001 because of CKD and who later started dialysis. The propensity score on multiple factors was used to match two groups of patients (AST-120 group, n = 78; non-AST-120 group, n = 78). Then, the proportion of patients remaining dialysis-free and the 50% dialysis-free period during the 24 months after starting treatment with or without AST-120 were analyzed. The impact of AST-120 on the risk of dialysis initiation was also determined by multivariate analysis. There were no significant differences in the clinical background and laboratory values after matching the two groups using the propensity score. The 50% dialysis-free period was significantly prolonged in the AST-120 group compared to the non-AST-120 group for all patients analyzed, as well as for the subgroup with diabetic or non-diabetic renal disease. When AST-120 treatment was started at a serum creatinine level below 3 mg/dL, the dialysis-free period was longer than 24 months in the AST-120 group, compared with 16.2 months in the non-AST-120 group. The 24-month dialysis-free rate was higher in the AST-120 group in every patient category. The risk of dialysis initiation was increased 3.48-fold in patients who were not administered AST-120. These results show that AST-120 delays the initiation of dialysis in CKD patients. Thus, AST-120 is an effective supplementary therapy to prevent the initiation of dialysis in CKD patients.     

Cross-clade neutralizing antibodies against HIV-1 induced in rabbits by focusing the immune response on a neutralizing epitope

Studies were performed to induce cross-clade neutralizing antibodies (Abs) by testing various combinations of prime and boost constructs that focus the immune response on structurally-conserved epitopes in the V3 loop of HIV-1 gp120. Rabbits were immunized with gp120 DNA containing a V3 loop characterized by the GPGR motif at its tip, and/or with gp120 DNA with a V3 loop carrying the GPGQ motif. Priming was followed by boosts with V3-fusion proteins (V3-FPs) carrying the V3 sequence from a subtype B virus (GPGR motif), and/or with V3 sequences from subtypes A and C (GPGQ motif). The broadest and most consistent neutralizing responses were generated when using a clade C gp120 DNA prime and with the V3_B-FP boost. Immune sera displayed neutralizing activity in three assays against pseudoviruses and primary isolates from subtypes A, AG, B, C, and D. Polyclonal Abs in the immune rabbit sera neutralized viruses that were not neutralized by pools of human anti-V3 monoclonal Abs. Greater than 80% of the neutralizing Abs were specific for V3, showing that the immune response could be focused on a neutralizing epitope and that vaccine-induced anti-V3 Abs have cross-clade neutralizing activity.     

CT120反义寡核苷酸抑制肺腺癌细胞A549的生长

目的 探讨CT120基因与肺腺癌细胞A549生长、分化的关系。方法 构建含有CT120基因的反义表达载体（命名为pcDNA3.1-CT120）,并将该载体转染肺腺癌细胞A549,应用G418筛选,获得了稳定表达CT120反义基因的克隆（命名为pcDNA3.1-CT120-A549）。RT-PCR和Western blot 检测CT120表达。流式细胞仪和软琼脂集落形成实验分析细胞生长,同时用RT-PCR检测P53、CYCLIND1 和CDK4的表达。结果 成功构建了含有CT120基因的反义表达载体,而且该载体能够有效抑制CT120在肺腺癌细胞A549中的表达。抑制CT120基因的表达能够抑制细胞的生长,促进细胞凋亡。在稳定表达CT120反义基因的克隆中P53表达明显上调,CYCLIND1 和CDK4表达明显下调。结论 反义寡核苷酸抑制CT120的表达有可能是肺癌基因治疗的一个新的靶点。     

Chemokine receptors and neurotrophic factors: Potential therapy against aids dementia?

Chemokine receptors, in particular, CXCR4 and CCR5, mediate human immunodeficiency virus type 1 (HIV-1) infection of immunocompetent cells and the apoptosis of these cells. However, the virus does not infect neurons. Yet through a variety of mechanisms, HIV promotes glial cell activation, synaptodendritic alterations, and neuronal loss that ultimately lead to motor and cognitive impairment. Chemokines and chemokine receptors are abundant in the adult central nervous system and play a role in neuronal apoptosis evoked by HIV proteins. Thus, reducing the availability of chemokine receptors may prevent the neuronal degeneration seen in HIV-positive patients. In this article, we present and discuss a recent experimental approach aimed at testing effective neuroprotective therapies against HIV-mediated neuronal degeneration.     

Pain catastrophizing in dental patients: Implications for treatment management

Background”Pain catastrophizing“ refers to an exaggerated negative mental set brought to bear during an actual or anticipated painful experience. A patient's perception of a dental care experience as catastrophic can result not only in poor satisfaction with the therapy but also in avoidance of necessary treatments, resulting in the deterioration of oral health.MethodsThe author reviewed literature regarding pain catastrophizing regarding dental treatment as well as behavioral models related to catastrophizing.ResultsPeople who catastrophize show excessive attention to pain (rumination), exaggerate the threat value of pain (magnification) and feel unable to cope with their suffering (helplessness). During dental treatments, greater pain catastrophizing is associated with increased pain, dental anxiety and negative thoughts regarding pain and dental procedures.ConclusionsIt is important that clinicians identify dental patients who catastrophize so as to plan and provide the best treatment for their needs.Practical ImplicationsTo manage the care of patients who catastrophize, the clinician can actively probe patients' pain experience, help them reappraise threat, manipulate their attention to pain and improve dentist-patient communication.