Determination of antitubercular drugs in human plasma by HPLC through direct injection

A simple and efficient method is described for the direct determination of Isoniazide (INH) and Pyrazinamide (PZAm) in human plasma, based on reversed-phase HPLC. A number of other antitubercular drugs such as p-Aminosalycylic acid (PAS), Streptomycin (STM) and Ethambutol (ETH) and the major metabolites of the two investigated drugs, namely N-Monoacetylisoniazide (AcINH) and Pyrazinoic acid (PZAc), were shown not to interfere with the assay method. A potential application of the method to routine clinical monitoring of antitubercular drugs is discussed.     

Analysis of the epsilon-sarcoglycan gene in familial and sporadic myoclonus-dystonia: evidence for genetic heterogeneity.

The epsilon-sarcoglycan gene (SGCE) on human chromosome 7q21 has been reported to be a major locus for inherited myoclonus-dystonia. Linkage to the SGCE locus has been detected in the majority of families tested, and mutations in the coding region have been found recently in families with autosomal dominant myoclonus-dystonia. To evaluate the relevance of SGCE in myoclonus-dystonia, we sequenced the entire coding region of the epsilon-sarcoglycan gene in 16 patients with either sporadic or familial myoclonus-dystonia. No mutations were found. This study suggests that epsilon-sarcoglycan does not play an important role in sporadic myoclonus-dystonia and supports genetic heterogeneity in familial cases.     

Multiple sclerosis and headache co-morbidity. A case-control study

The prevalence of primary headache (PH) in a multiple sclerosis (MS) sample vs. control healthy subjects was investigated at a neurological clinic in 2004–2005: 122 of 238 (51%) MS patients and 57 of 238 (23%) controls proved to be affected by headache. The groups did not differ for the rates of PH types. Headache types of MS patients were comparable to those of PH patients that were observed at the same institute in a case-control comparison. First symptoms of headache preceded those of MS in two thirds of cases. Headache features did not significantly change after MS onset. Comorbidity of MS and PH could be explained by some common clinical and biological traits.     

Viral load at the time of liver transplantation and risk of hepatitis B virus recurrence.

Hepatitis B virus (HBV) recurrence after liver transplantation is significantly reduced by prophylaxis with hepatitis B immune globulins (HBIG) or antiviral drugs in nonreplicating patients and by the combination of both drugs in replicating patients. However, the load of HBV DNA, which defines replicating status in patients undergoing liver transplantation, remains unclear. This study analyzes the correlation between the viral load, tested with a single amplified assay, at the time of liver transplantation, and the risk of hepatitis B recurrence in 177 HBV carriers who underwent transplantation in a single center from 1990 to 2002. Overall, HBV relapsed after surgery in 15 patients (8.5%) with a 5- and 8-year actuarial rate of recurrence of 8% and 21%, respectively. After liver transplantation hepatitis B recurred in 9% of 98 selected subjects treated only with immune globulins and in 8% of 79 viremic patients who received immune globulins and lamivudine (P = NS). A linear correlation was observed between recurrence and viral load at the time of surgery. In transplant patients with HBV DNA higher than 100,000 copies/mL, 200-99,999 copies/mL, and DNA undetectable by amplified assay, hepatitis B recurred in 50%, 7.5%, and 0% of patients, respectively. Overall, a viral load higher than 100,000 copies/mL at the time of liver transplantation was significantly associated with hepatitis B recurrence (P = .0003). In conclusion, spontaneous or antiviral-induced HBV DNA viral load at the time of surgery classifies the risk of HBV recurrence after liver transplantation and indicates the best prophylaxis strategy.     

Early assessment of renal resistance index after kidney transplant can help predict long-term renal function.

BACKGROUND: Color Doppler ultrasonography of intrarenal arterial resistance index (RI), performed early after kidney transplant, has proven to reliably predict short-term allograft function. The aim of this study was to assess whether it could also predict long-term renal function. METHODS: We retrospectively analysed 76 kidney transplant patients who underwent RI assessment within 1 month after the transplant, subdivided into two groups according to RI values, lower (group A) or higher (group B) than its median value (0.635). RESULTS: Compared with group A subjects, the patients of group B were older at the time of transplant (42 +/- 9 vs 35 +/- 8 years; P = 0.001), the donor age was also older (41 +/- 16 vs 33 +/- 13 years; P = 0.02) and had a slightly higher proteinuria (0.54 +/- 0.5 vs 0.32 +/- 0.2 g/24 h; P = 0.02). Serum creatinine, ciclosporin or tacrolimus trough level, arterial blood pressure, number of human leukocyte antigen (HLA) mismatches, anti-hypertensive medications and incidence of delayed graft function were not significantly different between the two groups. By univariate analysis, RI turned out to directly correlate with the recipient age, donor age and daily proteinuria (P = 0.007, P = 0.0007 and P = 0.02, respectively). Multivariate analysis showed that only donor and recipient age maintained their independent predictive value on RI. Kaplan-Meier analysis, considering a serum creatinine increase >50% as the endpoint of the study, showed a statistically significant different graft survival in the two groups (log-rank test = 5.489; P = 0.01). The univariate relative risk of deterioration of graft function among patients with higher RI was 3.77. Proteinuria and recipient age increased the risk as well. CONCLUSIONS: Our data seem to suggest that early determination of RI can help predict long-term graft function in kidney transplant recipients.     

Changes in pulmonary function test and cardio-pulmonary exercise capacity in COPD patients after lobar pulmonary resection.

OBJECTIVE: Pulmonary Function Tests (PFT) and Cardio-Pulmonary Exercise Testing (C-PET) are useful to evaluate operability in functionally compromised patients. Although modifications of PFT and C-PET after lung surgery have been widely explored, little information exists as to modifications of exercise capacity in COPD patients undergoing lung resection. We prospectively analyzed the changes in PFT and C-PET in patients with COPD after a pulmonary lobar resection. METHODS: From January 2003 to March 2004 all patients scheduled for lung resection were considered for participation in the study protocol. Those patients with a preoperative diagnosis of COPD on PFT were explored through a C-PET. Only patients who had undergone a lobar pulmonary resection were subsequently considered; these patients had a new complete cardio-respiratory evaluation 3 months after surgery. The pre- and postoperative values compared were those of FEV1, TLC, DLCO, VO2max, and VE/VCO2. Data are expressed as mean +/- standard deviation (SD). Statistic evaluation was made using the Wilcoxon test. RESULTS: During this period 11 patients completed the study protocol. Ten patients underwent surgery for NSCLC and one for a pulmonary aspergilloma. Nine lobectomies and two bilobectomies were performed. In the study population, the preoperative mean value of FEV1 resulted as being 53% (SD+/-20) of the predicted mean value, that of TLC 120% (SD+/-35) and that of DLCO 65% (SD+/-27). The preoperative mean value of VO2max resulted as being 17.8 ml/Kg/min (SD+/-3.25) and mean VE/VCO2 resulted as being 35.7 (SD+/-4). Three months after surgery the measured mean value of FEV1 was 53% (SD+/-18), that of TLC was 99% (SD+/-24) and that of DLCO 52% (SD+/-18). The mean value of VO2max resulted as being 14.1 ml/Kg/min (SD+/-3.04) and that of VE/VCO2 was 42.5 (SD+/-12.8). Statistical analysis of PFT values showed that FEV1 and DLCO were not significantly modified (P > 0.05); in contrast, TLC had significantly decreased (P = 0.008). VO2max had significantly decreased (P = 0.004) and VE/VCO2 had significantly increased (P = 0.018). CONCLUSIONS: Three months after a lobar pulmonary resection, patients with COPD were found to have a significant decrease in exercise tolerance. PFT alone can underestimate the postoperative loss of exercise capacity through exercise.     

Repetitive magnetic stimulation of cortical motor areas in Parkinson's disease: implications for the pathophysiology of cortical function.

We investigated the neurophysiological and clinical effects of repetitive magnetic stimulation (rTMS) delivered to the cortical motor areas in healthy subjects and patients with Parkinson's disease. rTMS was delivered with a high speed magnetic stimulator (Cadwell, Kennewick, WA) through a figure-eight coil centred on the primary motor area at a stimulus intensity of 120% motor threshold. Trains of 10 stimuli were delivered at frequencies of 5 Hz while subjects were at rest and during a voluntary contraction of the contralateral first dorsal interosseous muscle. In normal subjects at rest, the muscle evoked responses (MEPs) to each stimulus in a train of magnetic stimuli progressively increased in size during the train. rTMS left the MEPs unchanged in patients off therapy and had a small facilitatory effect in those on therapy. In normal subjects and patients, 5-Hz rTMS trains delivered during a voluntary contraction of the target muscle left the MEP unchanged in size. MEPs were followed by a silent period that increased in duration during the course of the train. The silent period duration increased to a similar extent in patients and controls. The reduced rTMS-induced facilitation of MEPs in patients with Parkinson's disease reflects a decreased facilitation of the excitatory cells in the cortical motor areas.     

How does prosthesis head size affect vibration transmission in ossiculoplasty?

OBJECTIVES: The transmission of vibrations from the tympanic membrane to the stapes footplate by an ossicular reconstruction prosthesis is affected by the size of the prosthesis head. We sought to determine if augmenting or reducing the head size of prosthesis had a systematic effect on transmission of vibrations to the stapes. STUDY DESIGN: We conducted a fresh cadaveric temporal bone middle ear study. METHODS: The incus was replaced with a prosthesis using a tympanic membrane to stapes head (TASH)-type hydroxyapatite prosthesis in nine fresh cadaveric temporal bones. Three prosthesis head sizes were created: unaltered, reduced, and augmented. Stapes vibrations were measured with a laser Doppler vibrometer in response to acoustic frequency chirps at 90 dB SPL. RESULTS: All three head size prostheses resulted in smaller stapes vibrations than the intact ear. There was no difference in the vibration transmission between the three different head sizes. All prostheses showed a vibration loss of 10 to 15 dB compared to the intact ear. CONCLUSIONS AND SIGNIFICANCE: Within the range of sizes tested, prosthesis head size had little impact on vibration transmission to the stapes footplate.     

Effect of Bendazac Lysine on lens and retina in diabetics

The possible beneficial effects on the lens and retina which Bendazac Lysine may have in the treatment of adult diabetic patients were investigated. Twenty patients, ranging in age from 54.80 ± 5.86 years old, were studied. The average duration of the diabetes was 11.32 ± 4.10 years. Thirteen patients had background retinopathy. The metabolic controls carried out during the study were satisfactory (HbA1<11%). Bendazac Lysine (500 mg three times a day) was administered for 6 months. Blood-retinal barrier permeability (VPR and VPRt) and lens transmittance (t) were evaluated prior to and 6 months after treatment by fluorophotometry. No statistically significant differences between the pre- and post-treatment values of the retina permeability were observed, however, there was a statistically significant improvement (p<0.05) (initial value: t= 0.813 ± 0.040 and final value: t=0.823 ± 0.037) in the lens transmittance. The authors conclude that Bendazac Lysine has a beneficial effect on the lens in the diabetic adult although no improvement in the permeability of the blood-retinal barrier has been observed.