Catheter-based transendocardial delivery of autologous bone-marrow-derived mononuclear cells in patients listed for heart transplantation

Growing evidence suggests that transplantation of autologous bone-marrow mononuclear cells (ABMMNCs) can improve the perfusion and contractile function of ischemic myocardium. This procedure could potentially benefit transplant candidates awaiting a donor heart. To study the safety and feasibility of ABMMNC injection, we performed a prospective, nonrandomized, open-label study in 5 heart transplant candidates with severe ischemic heart failure. Each patient underwent baseline single-photon emission computed tomography, a ramp treadmill protocol, 2-dimensional echocardiography, 24-hour Holter monitoring, and signal-averaged electrocardiography, which were repeated at 2 and 6 months. Transendocardial delivery of ABMMNCs was done with the aid of electromechanical mapping to identify viable myocardium. Each patient received 15 ABMMNC injections of 0.2 cc each. There were no deaths, significant arrhythmias, or other major complications. The ABMMNC injection reduced the amount of ischemic myocardium (not statistically significant). More important, exercise test results improved significantly. Myocardial volume oxygen consumption increased from 10.6 +/- 3 mL/kg/min (baseline) to 16.3 +/- 7 mL/kg/min (2 months) and 23 +/- 7 mL/kg/min (6 months) (P = 0.0091). In 4 of the 5 cases, this was such an improvement that the patients were no longer eligible for cardiac transplantation. In addition, metabolic equivalents improved from 3.03 +/- 0.66 (baseline) to 4.65 +/- 1.99 (2 months) and 6.5 +/- 2.0 (6 months) (P = 0.0092). In conclusion, ABMMNC injections were performed safely and resulted in improved exercise capacity. This technique may hold promise as an alternative to medical management in patients with severe ischemic heart failure who are ineligible for conventional revascularization.

Transendocardial, autologous bone marrow cell transplantation for severe, chronic ischemic heart failure

BACKGROUND

This study evaluated the hypothesis that transendocardial injections of autologous mononuclear bone marrow cells in patients with end-stage ischemic heart disease could safely promote neovascularization and improve perfusion and myocardial contractility.

METHODS AND RESULTS

Twenty-one patients were enrolled in this prospective, nonrandomized, open-label study (first 14 patients, treatment; last 7 patients, control). Baseline evaluations included complete clinical and laboratory evaluations, exercise stress (ramp treadmill), 2D Doppler echocardiogram, single-photon emission computed tomography perfusion scan, and 24-hour Holter monitoring. Bone marrow mononuclear cells were harvested, isolated, washed, and resuspended in saline for injection by NOGA catheter (15 injections of 0.2 cc). Electromechanical mapping was used to identify viable myocardium (unipolar voltage > or =6.9 mV) for treatment. Treated and control patients underwent 2-month noninvasive follow-up, and treated patients alone underwent a 4-month invasive follow-up according to standard protocols and with the same procedures used as at baseline. Patient population demographics and exercise test variables did not differ significantly between the treatment and control groups; only serum creatinine and brain natriuretic peptide levels varied in laboratory evaluations at follow-up, being relatively higher in control patients. At 2 months, there was a significant reduction in total reversible defect and improvement in global left ventricular function within the treatment group and between the treatment and control groups (P=0.02) on quantitative single-photon emission computed tomography analysis. At 4 months, there was improvement in ejection fraction from a baseline of 20% to 29% (P=0.003) and a reduction in end-systolic volume (P=0.03) in the treated patients. Electromechanical mapping revealed significant mechanical improvement of the injected segments (P<0.0005) at 4 months after treatment.

CONCLUSIONS

Thus, the present study demonstrates the relative safety of intramyocardial injections of bone marrow-derived stem cells in humans with severe heart failure and the potential for improving myocardial blood flow with associated enhancement of regional and global left ventricular function.

Haemophilus influenzae resistance in Latin America: systematic review of surveillance data

Haemophilus influenzae is a relevant cause of morbidity and mortality among children under 5 years of age in the developing world. In Latin America, H. influenzae type b (Hib) conjugate vaccine and surveillance of H. influenzae antimicrobial susceptibility have been implemented in recent years. We have undertaken a systematic review and a pooled analysis on H. influenzae antimicrobial resistance, including reports of 15 Latin America countries over a 10-year period (1990-2000). We have found that 450 (21.4%) of 2,100 invasive isolates were beta-lactamase producers compared to 145 (14.5%) of 998 isolates of noninvasive isolates (p < 0.05). Ampicillin resistance was detected among 783 (21.9%) of 3,577 invasive isolates compared to 111 (17.2%) of 646 noninvasive strains (p < 0.05). In contrast, 568 (41.9%) of 1,355 noninvasive strains were trimethoprim-sulfamethoxazole (TMP-SMX) resistance against 241 (26.9%) of 897 invasive ones (p < 0.05). Therefore, TMP-SMX resistance was more common in nonsterile fluids than in sterile fluids. Over time, rates of beta-lactamase-producing strains were stable in Brazil and Mexico, whereas rates of TMP-SMX resistance were increasing in Brazil. It is predictable that following the Hib immunization, Latin America countries will be faced with increased nontypeable H. influenzae infection. Although standing by the nontypeable H. influenzae vaccine, in this novel epidemiological scenario of post-Hib vaccination in Latin America settings there is a need to improve H. influenzae resistance monitoring to guide clinicians to choose efficacious antimicrobial therapy.

Krametosan, a new trinorlignan from the roots of Krameria tomentosa

A new phenylcoumarone type trinorlignan, krametosan (1), along with the known norlignans, ratanhiaphenol I (2) and 2-(2'-hydroxy-4',6'-dimethoxyphenyl)-5-(E)-propenylbenzofuran (3), the lignan conocarpan (4) and dinorlignan decurrenal (5), were isolated from the CHCl3 extract of the roots of Krameria tomentosa. The structure of these compounds were elucidated by the spectroscopic methods.

[Seroepidemiological profile of hepatitis B infection in staff at hemodialysis units of Goiânia-Goiás, Central Brazil]

In order to investigate the hepatitis B virus (HBV) infection profile in hemodialysis staff (n = 152) of Goiânia,Goiás, blood samples were tested for detection of HBsAg, anti-HBs and anti-HBc markers. An overall HBV infection prevalence of 24.3% (CI 95%: 17.8 - 32) was found. Multivariate analysis of risk factors showed that length of employment, history of occupational exposure and nonuse of protective equipment were significantly associated with HBV seropositivity. Of 40 staff members who were susceptible to this infection, 20 agreed to participate in the vaccination program. After three vaccine doses (Euvax-B), 18 (90%) seroconverted to anti-HBs with titers >/= 10 IU/L. These data suggest the dialytic environmental as a possible source of occupational transmission of HBV, and emphasize the need to evaluate strategies of control and prevention to be followed in these units.

[Differential patterns of neonatal and post-neonatal mortality rates in Goiânia, Brazil, 1992-1996: use of spatial analysis to identify high-risk areas]

The aim of this study was to investigate the spatial pattern of neonatal and post-neonatal mortality in the city of Goiânia, Central Brazil. Analyses were based on linked birth and death certificates relating to 101,000 in-hospital live births from mothers residing in the city of Goiânia over the 1992-1996 period. Overall neonatal and post-neonatal mortality probabilities were calculated using the linked database. The empirical Bayes method was applied to smooth the estimated rates and minimize random fluctuation. Spatial units of analysis were 65 urban districts, corresponding to the urban planning sectors. The following exploratory spatial analyses were applied: "global" Moran's I statistic, local Moran LISA map, and Gi* local statistics. For both neonatal and post-neonatal mortality there was statistically significant spatial autocorrelation. Results of post-neonatal mortality showed a high-risk cluster located on the outskirts of the city. For the neonatal period, a heterogeneous mortality pattern was found with high-risk districts in all regions, including central areas.

Hepatitis C prevalence and risk factors in hemodialysis patients in Central Brazil: a survey by polymerase chain reaction and serological methods

An hemodialysis population in Central Brazil was screened by polymerase chain reaction (PCR) and serological methods to assess the prevalence of hepatitis C virus (HCV) infection and to investigate associated risk factors. All hemodialysis patients (n=428) were interviewed in eight dialysis units in Goiânia city. Blood samples were collected and serum samples screened for anti-HCV antibodies by an enzyme-linked immunosorbent assay (ELISA). Positive samples were retested for confirmation with a line immunoassay (LIA). All samples were also tested for HCV RNA by the PCR. An overall prevalence of 46.7% (CI 95%: 42-51.5) was found, ranging from 20.7% (CI 95%: 8.8-38.1) to 90.4% (CI 95%: 79.9-96.4) depending on the dialysis unit. Of the 428 patients, 185 were found to be seropositive by ELISA, and 167 were confirmed positive by LIA, resulting in an anti-HCV prevalence of 39%. A total of 131 patients were HCV RNA-positive. HCV viremia was present in 63.5% of the anti-HCV-positive patients and in 10.3% of the anti-HCV-negative patients. Univariate analysis of risk factors showed that the number of previous blood transfusions, transfusion of blood before mandatory screening for anti-HCV, length of time on hemodialysis, and treatment in multiple units were associated with HCV positivity. However, multivariate analysis revealed that blood transfusion before screening for anti-HCV and length of time on hemodialysis were significantly associated with HCV infection in this population. These data suggest that nosocomial transmission may play a role in the spread of HCV in the dialysis units studied. In addition to anti-HCV screening, HCV RNA detection is necessary for the diagnosis of HCV infection in hemodialysis patients.

Single lesion paucibacillary leprosy: baseline profile of the Brazilian Multicenter Cohort Study

In Brazil, there is little information about the clinical and epidemiological characteristics of paucibacillary, single skin lesion leprosy patients (SSL-PB). Only recently has the official notification system distinguished leprosy patients with a single lesion as a clinical entity, for whom the single-dose ROM (rifampin, ofloxacin and minocycline) regimen has been recommended. In this paper, we describe the baseline clinical features and the immunological background of a multicenter cohort of SSL-PB leprosy cases enrolled between December 1997-1998. Patients were recruited at health centers located in the following regions: Southeast = Rio de Janeiro; North = Amazon and Rondônia states and Center-West = Goiás state. Eligible cases were newly detected, untreated single-lesion leprosy patients without thickened nerve involvement, and were assessed by clinical, bacilloscopic and histopathological exams. The Mitsuda skin test and anti-PGL-I serology (ELISA) were also performed. Of the 299 SSL-PB leprosy patients, 259 (86.6%) fulfilled the criteria for single-dose ROM intervention. Our results showed that patients recruited from different sites had similar features, considering the clinical and immunological profiles. There was a predominance of adults (mean age 32.4; S.D. = 16.0), and a BCG scar was detected in 76.7% of the children (< or = 15 years old). Only 7 cases were diagnosed as the multibacillary type, representing less than 3% of the patients being misclassified. Our data indicate that in Brazil SSL-PB case ascertainment based on clinical and bacilloscopic criteria can be accurately defined under a routine control program; 75.0% of SSL-PB cases were Mitsuda positive (> or = 5 mm) and seropositivity for anti-PGL-I was detected in 17.3% of the patients. These data are compatible with effective cell-mediated immunity and low bacillary load, suggesting favorable clinical outcomes for most SSL-PB participants of this cohort.

Nested-PCR using MPB64 fragment improves the diagnosis of pleural and meningeal tuberculosis

Fluids in which Mycobacterium tuberculosis are seldom found, such as pleural and cerebrospinal liquids, are good candidates to be studied using PCR techniques. We detail our experience with a PCR assay applied to pleural and cerebrospinal fluids using the primer MPB64. Seventy three specimens were analyzed: 30 pleural fluids (PF), 26 pleural biopsies (PB) and 17 cerebrospinal fluids (CSF). The gold standard for the diagnosis of tuberculous meningitis was the positive culture for M. tuberculosis in CSF. Tuberculous pleural effusion was diagnosed when cultures of PF and/or PB were positive for M. tuberculosis, or the PB histology showed granulomas. Our results, compared to the gold standards employed, showed a sensitivity of 70%, specificity of 88%, positive predictive value of 82% and negative predictive value of 80%. The high specificity of the MPB64 fragment while still retaining a good sensitivity makes it very well suited for pleural and cerebrospinal tuberculosis diagnosis.

[Surveillance of endemic diseases in urban areas: the interface between census tract maps and morbidity data]

In this article we discuss the methodological issues associated with the creation of a surveillance system for endemic diseases in urban areas based on analysis of populations at risk and on spatially referenced epidemiological indicators. We comment on the system's basic requirements, selection criteria for socioeconomic variables, and methodological steps to combine these variables so as to construct a census-based deprivation index. We also present the ways we solved some operational problems related to generation of digitized census tracts maps and linkage of morbidity data from different sources. This approach, spatial organization into account in surveillance of endemic diseases, exemplified here by tuberculosis and leprosy, allows for the interaction of several official data sets from census and health services in order to geographically discriminate inner-city risk strata. Criteria for constructing these risk strata were considered a useful tool for health planning and management activities for the control of endemic diseases in cities.

Early electrocardiographic abnormalities in Trypanosoma cruzi-seropositive children

As part of a major epidemiologic study on Chagas' disease, we compared the prevalence of electrocardiographic (ECG) abnormalities among 141 school children 7-12 years of age and seropositive for Trypanosoma cruzi, and 282 age-, sex-, and school-matched seronegative children in an endemic area in Brazil. The prevalence of ECG abnormalities was 11.3% among seropositive children and 3.5% among seronegative children (odds ratio = 3.5, 95% confidence interval [CI] = 1.5-8.4). The prevalence rate of ECG alterations was 10.7% for seropositive males versus 8.9% for seropositive females. Complete right bundle branch block (CRBBB), which is highly suggestive of Chagas' disease cardiopathy, was diagnosed in nine (6.4%) seropositive children and in only one (0.3%) seronegative child (odds ratio = 18.5, 95% CI = 2.3-146.5, attributable fraction = 58.3%). Five incident new cases of CRBBB were diagnosed after a 36-month follow-up of seropositive children who were enrolled in an independent clinical field trial. No case of frequent and/or multifocal ventricular premature beats was found in the cohort of children. The surprisingly high frequency of early ECG abnormalities, which indicates a rapid evolution from infection to disease, suggests the existence of endemic areas with a particular accelerated disease progression that was not described before. Under such conditions, a public health chemotherapy program focusing on the treatment of young seropositive children would be recommended.

[Eradication of leprosy in the Americas: current status and perspectives]

Leprosy, a disease that used to be shrouded in darkness and fear, can now be cured thanks to a multidrug treatment schedule with rifampicin, clofazimine, and dapsone which has been in use since 1981. In 1991 the World Health Assembly, encouraged by the efficacy of this treatment regimen, established the goal of eliminating the disease as a public health problem globally and nationally by the year 2000. This goal, which calls for reducing disease prevalence to less than one case per 10,000 inhabitants, should not be confused with the goal of eradicating the disease, which implies a complete interruption of its transmission. Eliminating leprosy is an attainable goal which will depend on the forceful and massive use of the multidrug treatment regimen. This paper describes and discusses the various initiatives that have been launched in Latin America for the purpose of achieving this goal and the results obtained so far. It also explores the factors that impact on the feasibility of eradicating the disease.

Hepatitis B virus infection profile in central Brazilian hemodialysis population

Hepatitis B has proved to be a major health hazard in hemodialysis patients. In order to investigate the hepatitis B virus (HBV) infection profile in the hemodialysis population of Goiânia city--Central Brazil, all dialysis patients (N = 282) were studied. The prevalence of any HBV marker (HBsAg, anti-HBs, and anti-HBc) was 56.7% (95% CI: 51.1-62.7), ranging from 33.3% to 77.7% depending on dialysis unit. HBV-DNA was detected in 67.6% and 88.2% of the HBsAg-positive serum samples, in 91.3% and 100% of the HBsAg/HBeAg-positive samples, and in 18.2% and 63.6% of the HBsAg/anti-HBe-reactive sera by hybridization and PCR, respectively. The length of time on hemodialysis was significantly associated with HBV seropositivity. Only 10% of the patients reported received hepatitis B vaccination. The findings of a high HBV infection prevalence in this population and the increased risk for HBV infection on long-term hemodialysis suggest the environmental transmission, emphasizing the urgent need to evaluate strategies of control and prevention followed in these units.

Trypanosoma cruzi stocks isolated from acute Chagas disease patients lead to lethal murine infection

Ten Trypanosoma cruzi stocks recently isolated from patients in acute and chronic phases of Chagas disease were inoculated to susceptible (A/Sn) mice. The mice were inoculated with 10(4) trypomastigotes intraperitoneally and monitored for parasitaemia and mortality for up to 300 d. The results demonstrated that (i) T. cruzi stocks isolated from patients in the acute phase killed animals, while stocks from patients in the chronic phase did not; (ii) survival curves differed statistically among mice infected with lethal stocks, and (iii) parasite burden did not affect the mortality rate of mice.