The use of biodiversity as source of new chemical entities against defined molecular targets for treatment of malaria, tuberculosis, and T-cell mediated diseases: a review

The modern approach to the development of new chemical entities against complex diseases, especially the neglected endemic diseases such as tuberculosis and malaria, is based on the use of defined molecular targets. Among the advantages, this approach allows (i) the search and identification of lead compounds with defined molecular mechanisms against a defined target (e.g. enzymes from defined pathways), (ii) the analysis of a great number of compounds with a favorable cost/benefit ratio, (iii) the development even in the initial stages of compounds with selective toxicity (the fundamental principle of chemotherapy), (iv) the evaluation of plant extracts as well as of pure substances. The current use of such technology, unfortunately, is concentrated in developed countries, especially in the big pharma. This fact contributes in a significant way to hamper the development of innovative new compounds to treat neglected diseases. The large biodiversity within the territory of Brazil puts the country in a strategic position to develop the rational and sustained exploration of new metabolites of therapeutic value. The extension of the country covers a wide range of climates, soil types, and altitudes, providing a unique set of selective pressures for the adaptation of plant life in these scenarios. Chemical diversity is also driven by these forces, in an attempt to best fit the plant communities to the particular abiotic stresses, fauna, and microbes that co-exist with them. Certain areas of vegetation (Amazonian Forest, Atlantic Forest, Araucaria Forest, Cerrado-Brazilian Savanna, and Caatinga) are rich in species and types of environments to be used to search for natural compounds active against tuberculosis, malaria, and chronic-degenerative diseases. The present review describes some strategies to search for natural compounds, whose choice can be based on ethnobotanical and chemotaxonomical studies, and screen for their ability to bind to immobilized drug targets and to inhibit their activities. Molecular cloning, gene knockout, protein expression and purification, N-terminal sequencing, and mass spectrometry are the methods of choice to provide homogeneous drug targets for immobilization by optimized chemical reactions. Plant extract preparations, fractionation of promising plant extracts, propagation protocols and definition of in planta studies to maximize product yield of plant species producing active compounds have to be performed to provide a continuing supply of bioactive materials. Chemical characterization of natural compounds, determination of mode of action by kinetics and other spectroscopic methods (MS, X-ray, NMR), as well as in vitro and in vivo biological assays, chemical derivatization, and structure-activity relationships have to be carried out to provide a thorough knowledge on which to base the search for natural compounds or their derivatives with biological activity.

An international, randomized, double-blind, placebo-controlled, phase III trial of pregabalin monotherapy in treatment of patients with fibromyalgia.

OBJECTIVE: To evaluate the efficacy and safety of pregabalin monotherapy versus placebo for symptomatic pain relief and improvement of patient global assessment in patients with fibromyalgia (FM) enrolled from countries outside the United States. METHODS: This international, multicenter, double-blind, placebo-controlled trial randomly assigned 747 patients with FM to placebo or 300, 450, or 600 mg/day pregabalin twice daily for 14 weeks. Primary efficacy measures were endpoint mean pain scores and Patient Global Impression of Change (PGIC). Secondary outcomes included assessments of sleep and function. RESULTS: Patients in the 450 mg/day pregabalin group showed significant improvements versus placebo in endpoint mean pain score (-0.56; p = 0.0132), PGIC (73% improved vs 56% placebo; p = 0.0017), and function [Fibromyalgia Impact Questionnaire (FIQ) total score -5.85; p = 0.0012]. PGIC was also significant for 600 mg/day pregabalin (69% improved; p = 0.0227). Results for these endpoints were nonsignificant for pregabalin at 300 mg/day and for pain and FIQ score at 600 mg/day. Early onset of pain relief was seen, with separation from placebo detected by Week 1 in all pregabalin groups. All pregabalin doses demonstrated superiority to placebo on the Medical Outcomes Study-Sleep Scale Sleep Disturbance subscale and the Sleep Quality diary. Dizziness and somnolence were the most frequently reported adverse events. CONCLUSION: Pregabalin demonstrated modest efficacy in pain, global assessment, and function in FM at 450 mg/day, and improved sleep across all dose levels, but it did not provide consistent evidence of benefit at 300 and 600 mg/day in this study. Pregabalin was generally well tolerated for the treatment of FM. (Clinical trial registry NCT00333866).

Impact of previous virological treatment failures and adherence on the outcome of antiretroviral therapy in 2007.

BACKGROUND: Combination antiretroviral treatment (cART) has been very successful, especially among selected patients in clinical trials. The aim of this study was to describe outcomes of cART on the population level in a large national cohort. METHODS: Characteristics of participants of the Swiss HIV Cohort Study on stable cART at two semiannual visits in 2007 were analyzed with respect to era of treatment initiation, number of previous virologically failed regimens and self reported adherence. Starting ART in the mono/dual era before HIV-1 RNA assays became available was counted as one failed regimen. Logistic regression was used to identify risk factors for virological failure between the two consecutive visits. RESULTS: Of 4541 patients 31.2% and 68.8% had initiated therapy in the mono/dual and cART era, respectively, and been on treatment for a median of 11.7 vs. 5.7 years. At visit 1 in 2007, the mean number of previous failed regimens was 3.2 vs. 0.5 and the viral load was undetectable (<50 copies/ml) in 84.6% vs. 89.1% of the participants, respectively. Adjusted odds ratios of a detectable viral load at visit 2 for participants from the mono/dual era with a history of 2 and 3, 4, >4 previous failures compared to 1 were 0.9 (95% CI 0.4-1.7), 0.8 (0.4-1.6), 1.6 (0.8-3.2), 3.3 (1.7-6.6) respectively, and 2.3 (1.1-4.8) for >2 missed cART doses during the last month, compared to perfect adherence. From the cART era, odds ratios with a history of 1, 2 and >2 previous failures compared to none were 1.8 (95% CI 1.3-2.5), 2.8 (1.7-4.5) and 7.8 (4.5-13.5), respectively, and 2.8 (1.6-4.8) for >2 missed cART doses during the last month, compared to perfect adherence. CONCLUSIONS: A higher number of previous virologically failed regimens, and imperfect adherence to therapy were independent predictors of imminent virological failure.

Changes in antihypertensive drug treatment in the general population: the Colaus Study

Background and aims: there is little information regar ding changes in antihypertensive drug treatment in Switzerland. We aimed at assessing those changes in a population-based, prospective study. Methods: 768 hypertensive subjects (372 women, 397 men) followed for 5 years. Subjects were defined as continuers (no change), switchers (one antihypertensive class replace by another), combiners (one antihypertensive class added) and discontinuers (stopped treatment). Results: Analysis of all patients (mono or combination therapy) showed that 54.6% were continuers, 27.2% combiners, 12.9% switchers and 5.3 % discontinuers. Similar findings were obtained for participants on monotherapy only: 42.2% continuers, 36.7% combiners, 13.4% switchers and 7.7% discontinuers. Combiners had higher systolic and diastolic blood pressure values at baseline than the other groups (p<0.001), while no difference were found for personal and family history and other clinical and biological variables. Compared to continuers, combiners and switchers improved their blood pressure status at follow-up: 26.7% of combiners and 26.3% of switchers improved, versus 17.7% of continuers and 7.3% of discontinuers (p<0.001). Among participants on monotherapy at baseline, continuation was greatest for angiotensin II type 1 receptor blocking agents (ARBs, 53.1%), angiotensin-converting enzyme inhibitors (44.4%) and β-blockers (41.8%). Only one quarter of participants treated with diuretic or calcium channel blockers at baseline remained so at follow-up. Conclusion: Antihypertensivedrug treatment is very stable in Switzerland. There are no big differences in persistence between antihypertensive classes, even if ARBs had the most favorable utilization pattern. Changes are only due to blood pressure level and improve blood pressure status.

Antiretroviral treatment during pregnancy.

OBJECTIVE: Virologic failure of HIV-positive patients is of special concern during pregnancy. We compared virologic failure and the frequency of treatment changes in pregnant and non-pregnant women of the Swiss HIV Cohort Study. METHODS: Using data on 372 pregnancies in 324 women we describe antiretroviral therapy during pregnancy. Pregnant women on HAART at conception (n = 131) were matched to 228 non-pregnant women (interindividual comparison) and to a time period of equal length before and after pregnancy (intraindividual comparison). Women starting HAART during pregnancy (n = 145) were compared with 578 non-pregnant women starting HAART. FINDINGS: The median age at conception was 31 years, 16% (n = 50) were infected through injecting drug use and the median CD4 cell count was 489 cells/microl. In the majority of pregnancies (n = 220, 59%), women had started ART before conception. When ART was started during pregnancy (n = 145, 39%), it was mainly during the second trimester (n = 100, 69%). Two thirds (n = 26) of 35 women starting in the third trimester were diagnosed with HIV during pregnancy. The risk of virologic failure tended to be lower in pregnant than in non-pregnant women [adjusted odds ratio 0.52 (95% confidence interval 0.25-1.09, P = 0.08)], but was similar in the intraindividual comparison (adjusted odds ratio 1.04, 95% confidence interval 0.48-2.28). Women starting HAART during pregnancy changed the treatment less often than non-pregnant women. CONCLUSION: Despite the physiological changes occurring during pregnancy, HIV infected pregnant women are not at higher risk of virologic failure.

Oral mucosal melanoma: conservative treatment including laser surgery.

Objective: To discuss the convenience of laser surgery as optimal treatment for melanoma of the oral mucosa.Patients and methods: A retrospective evaluation of four patients with primary oral melanomas treated at a single Cancer Institution in Mexico City.Results: Two patients were treated with resection of the melanoma with CO2 laser together with extraction of the involved dental organs and curettage of the alveolar walls. These two cases had melanoma in situ with multiple isolated foci. The third patient had a lesion with vertical growth, who was submitted to partial maxillectomy along with selective dissection of bilateral neck levels I-V with a negative report and the fourth patient had a history of oral nodular melanoma and presented with lymph node metastasis. According to follow-up status, there was no distant metastasis in any of the patients reported here.Conclusion: In our experience, conservative management with CO2 laser is adequate for melanomas of the oral mucosa with extraction of the dental organs and curettage of the alveoli to achieve complete surgical resection microscopically without sacrifice of the quality of life. Management of the neck is controversial. We recommend selective therapeutic resection of the neck only if it is found to be clinically positive. Elective dissection has not shown to have an impact in overall survival.

Clinical characteristics, prognosis, and treatment of pelvic cryptorchid seminoma.

PURPOSE: To analyze the clinical characteristics, prognosis, and treatment outcome of pelvic cryptorchid seminoma (PCS), and to determine whether whole abdominal-pelvic irradiation for Stage I disease is necessary. METHODS AND MATERIALS: From 1958 to 1991, 60 patients with PCS were treated at the Cancer Hospital of Chinese Academy of Medical Sciences, Beijing. They presented with a lower abdominal mass and showed a predominance for the right side. A high proportion of patients with PCS [26 of 60 (43%)] had metastatic disease, compared to 20% of those with scrotal seminoma, and there was a tendency toward a higher frequency of pelvic nodal metastases. There were 34 Stage I, 6 Stage IIA, 11 Stage IIB, 5 Stage III, and 4 Stage IV patients. Of these 60 patients, 56 underwent laparotomy with or without cryptorchiectomy (37 radical orchiectomy, 7 partial orchiectomy, and 12 biopsy of the primary or cervical node), and 4 cervical node biopsy only. All patients were further treated with radiotherapy, chemotherapy, or a combination of both. Patients with Stage I and II disease received radiotherapy, whereas patients with Stage III and IV were treated with chemotherapy. RESULTS: The overall and disease-free survivals at 5 and 10 years were 92% and 87%, and 88% and 84%, respectively. The 5- and 10-year survivals were 100% for Stage I, 94% and 87% for Stage II, and 56% and 42% for Stage III/IV, respectively (p < 0.05). Volume of irradiation, i.e., whole abdominal-pelvic radiotherapy (10 patients), versus hockey-stick encompassing paraaortic, ipsilateral iliac nodes and the primary tumor or tumor bed (17) did not influence outcome in Stage I patients. Five patients relapsed within 2-12 years after treatment, and four of these patients were successfully salvaged. Four patients developed a second malignant tumor and died. CONCLUSION: Stage I and II PCS can be adequately controlled by radiotherapy regardless of the surgical procedure. Whole abdominal-pelvic irradiation for Stage I and IIA disease is not required, and fields can be limited to the paraaortic, ipsilateral iliac nodes and primary tumor or tumor bed. We recommend platinum-based chemotherapy for Stage IIB-IV PCS.

Anti-TNF Therapy in the Treatment of Psoriasis in a Patient with Acute-on-Chronic Pancreatitis.

Background: Psoriasis is accepted as a multisystemic disease with several important systemic manifestations. Thus, underlying comorbidities have to be taken into account in the choice of treatment. Objective: To explore the role of anti-TNF therapy in the treatment of psoriasis in a patient with acute-on-chronic pancreatitis. Methods: Here, we present the case of a 75-year-old patient with severe psoriasis also suffering from chronic alcohol-induced pancreatitis with recurrent acute flares. A recent life-threatening episode of acute pancreatitis and ischemic liver precluded the reintroduction of methotrexate. Cyclosporine was also excluded as it has been reported to induce acute pancreatitis. Thus, an anti-TNF treatment was initiated in close collaboration with a gastroenterologist. Results: A year after starting anti-TNF therapy the patient continues to show complete clinical remission of his psoriasis. No side effects, particularly no bacterial infections, were reported. No relapses of the patient's underlying chronic pancreatitis were observed throughout the entire treatment with regular clinical and laboratory monitoring, suggesting that chronic pancreatitis is not per se a contraindication for anti-TNF therapy. Conclusion: This case study opens the way for further questioning on the role of TNF in the pathogenesis of chronic and acute pancreatitis and the use of anti-TNF therapy in its treatment. © 2013 S. Karger AG, Basel.

Combined cetuximab and trastuzumab are superior to gemcitabine in the treatment of human pancreatic carcinoma xenografts.

BACKGROUND: Pancreatic carcinoma remains a treatment-refractory cancer with a poor prognosis. Here, we compared anti-epidermal growth factor receptor (EGFR) and anti-HER2 monoclonal antibodies (2mAbs) injections with standard gemcitabine treatment on human pancreatic carcinoma xenografts. MATERIALS AND METHODS: Nude mice, bearing human pancreatic carcinoma xenografts, were treated with either combined anti-EGFR (cetuximab) and anti-HER2 (trastuzumab) or gemcitabine, and tumor growth was observed. RESULTS AND CONCLUSION: In first-line therapy, mice survival was significantly longer in the 2mAbs group compared with gemcitabine (P < 0.0001 for BxPC-3, P = 0.0679 for MiaPaCa-2 and P = 0.0019 for Capan-1) and with controls (P < 0.0001). In second-line therapy, tumor regressions were observed after replacing gemcitabine by 2mAbs treatment, resulting in significantly longer animal survival compared with mice receiving continuous gemcitabine injections (P = 0.008 for BxPC-3, P = 0.05 for MiaPaCa-2 and P < 0.001 for Capan-1). Therapeutic benefit of 2mAbs was observed despite K-Ras mutation. Interestingly, concerning the mechanism of action, coinjection of F(ab')(2) fragments from 2mAbs induced significant tumor growth inhibition, compared with controls (P = 0.001), indicating that the 2mAbs had an Fc fragment-independent direct action on tumor cells. This preclinical study demonstrated a significant improvement of survival and tumor regression in mice treated with anti-EGFR/anti-HER2 2mAbs in first- and second-line treatments, compared with gemcitabine, independently of the K-Ras status.

Increased α2- and β1-adrenoceptor densities in postmortem brain of subjects with depression: differential effect of antidepressant treatment.

BACKGROUND: Brain α2- and β-adrenoceptor alterations have been suggested in suicide and major depressive disorder. METHODS: The densities of α2-, β1- and β2-adrenoceptors in postmortem prefrontal cortex of 26 subjects with depression were compared with those of age-, gender- and postmortem delay-matched controls. The effect of antidepressant treatment on α2- and β-adrenoceptor densities was also evaluated. α2- and β-adrenoceptor densities were measured by saturation experiments with respective radioligands [(3)H]UK14304 and [(3)H]CGP12177. β1- and β2-adrenoceptor subtype densities were dissected by means of β1-adrenoceptor selective antagonist CGP20712A. RESULTS: Both, α2- and β1-adrenoceptors densities were higher in antidepressant-free depressed subjects (n=14) than those in matched controls (Δ~24%, p=0.013 and Δ~20%, p=0.044, respectively). In antidepressant-treated subjects (n=12), α2-adrenoceptor density remained increased over that in controls (Δ~20%), suggesting a resistance of α2-adrenoceptors to the down-regulatory effect of antidepressants. By contrast, β1-adrenoceptor density in antidepressant-treated depressed subjects was not different from controls, suggesting a possible down-regulation by antidepressants. The down-regulation of β1-adrenoceptor density in antidepressant-treated depressed subjects differs from the unaltered β1-adrenoceptor density observed in citalopram-treated rats and in a group of non-depressed subjects also treated with antidepressants (n=6). β2-adrenoceptor density was not altered in depressed subjects independently of treatment. LIMITATIONS: Antidepressant-treated subjects had been treated with a heterogeneous variety of antidepressant drugs. The results should be understood in the context of suicide victims with depression. CONCLUSIONS: These results show the up-regulation of brain α2- and β1-adrenoceptors in depression and suggest that the regulation induced by chronic antidepressant treatment would be altered in these subjects.

Virologic and immunologic responses in treatment-naive patients to ritonavir-boosted atazanavir or efavirenz with a common backbone.

Background: Atazanavir boosted with ritonavir (ATV/r) and efavirenz (EFV) are both recommended as first-line therapies for HIV-infected patients. We compared the 2 therapies for virologic efficacy and immune recovery. Methods: We included all treatment-naïve patients in the Swiss HIV Cohort Study starting therapy after May 2003 with either ATV/r or EFV and a backbone of tenofovir and either emtricitabine or lamivudine. We used Cox models to assess time to virologic failure and repeated measures models to assess the change in CD4 cell counts over time. All models were fit as marginal structural models using both point of treatment and censoring weights. Intent-to-treat and various as-treated analyses were carried out: In the latter, patients were censored at their last recorded measurement if they changed therapy or if they were no longer adherent to therapy. Results: Patients starting EFV (n = 1,097) and ATV/r (n = 384) were followed for a median of 35 and 37 months, respectively. During follow-up, 51% patients on EFV and 33% patients on ATV/r remained adherent and made no change to their first-line therapy. Although intent-to-treat analyses suggest virologic failure was more likely with ATV/r, there was no evidence for this disadvantage in patients who adhered to first-line therapy. Patients starting ATV/r had a greater increase in CD4 cell count during the first year of therapy, but this advantage disappeared after one year. Conclusions: In this observational study, there was no good evidence of any intrinsic advantage for one therapy over the other, consistent with earlier clinical trials. Differences between therapies may arise in a clinical setting because of differences in adherence to therapy.

Efficacy of benznidazol treatment for asymptomatic chagasic patients from state of Rio Grande do Sul evaluated during a three years follow-up

The efficacy of benznidazol on the treatment of chagasic patients from the state of Rio Grande do Sul was evaluated during a three-year follow-up. A cohort of 80 asymptomatic chronic chagasic patients or blood bank donors (49 male and 31 female) was studied. Their ages varied from 17-42 years, with a mean and a median of 30 and 35 years, respectively. The 80 patients presented positive serology, hemoculture and polymerase chain reaction (PCR). They were treated with 5 mg/Kg benznidazol twice a day for 60 days. Serological, parasitological and PCR methods were used to evaluate response. Serology was performed using commercial ELISA and indirect immunofluorescence (IFI) tests, parasitemia was monitored by hemoculture in LIT medium and PCR with primers S35/S36 was used to amplify a Trypanosoma cruzi 330 bp kDNA repetitive sequence. PCR positivity of 240 seropositive individuals was compared using DNA preparations from whole blood/guanidine EDTA (GE), buffy-coat/GE and frozen buffy-coat. Fifty non-chagasic individuals were used as negative controls. PCR positivity was 86.7% for the frozen buffy-coat, 71.7% for the GE/buffy-coat and 69.2% for the GE/whole blood. The hemocultures became negative just after treatment and remained negative during the three years of follow-up. In the third year after treatment, 9/80 (11.3%) patients presented negative PCR and, from those, four also presented negative serological tests. Furthermore, a reduction in three serological titers was observed in 27/80 (33.8%) of the patients treated. Taken together, the results show that four of the 80 (5.0%) chronic chagasic patients from the state of Rio Grande do Sul were cured after treatment with benznidazol.

Treatment rationale and study design for a phase III, double-blind, placebo-controlled study of maintenance pemetrexed plus best supportive care versus best supportive care immediately following induction treatment with pemetrexed plus cisplatin for advanced nonsquamous non-small cell lung cancer.

BACKGROUND: To improve the efficacy of first-line therapy for advanced non-small cell lung cancer (NSCLC), additional maintenance chemotherapy may be given after initial induction chemotherapy in patients who did not progress during the initial treatment, rather than waiting for disease progression to administer second-line treatment. Maintenance therapy may consist of an agent that either was or was not present in the induction regimen. The antifolate pemetrexed is efficacious in combination with cisplatin for first-line treatment of advanced NSCLC and has shown efficacy as a maintenance agent in studies in which it was not included in the induction regimen. We designed a phase III study to determine if pemetrexed maintenance therapy improves progression-free survival (PFS) and overall survival (OS) after cisplatin/pemetrexed induction therapy in patients with advanced nonsquamous NSCLC. Furthermore, since evidence suggests expression levels of thymidylate synthase, the primary target of pemetrexed, may be associated with responsiveness to pemetrexed, translational research will address whether thymidylate synthase expression correlates with efficacy outcomes of pemetrexed. METHODS/DESIGN: Approximately 900 patients will receive four cycles of induction chemotherapy consisting of pemetrexed (500 mg/m2) and cisplatin (75 mg/m2) on day 1 of a 21-day cycle. Patients with an Eastern Cooperative Oncology Group performance status of 0 or 1 who have not progressed during induction therapy will randomly receive (in a 2:1 ratio) one of two double-blind maintenance regimens: pemetrexed (500 mg/m2 on day 1 of a 21-day cycle) plus best supportive care (BSC) or placebo plus BSC. The primary objective is to compare PFS between treatment arms. Secondary objectives include a fully powered analysis of OS, objective tumor response rate, patient-reported outcomes, resource utilization, and toxicity. Tumor specimens for translational research will be obtained from consenting patients before induction treatment, with a second biopsy performed in eligible patients following the induction phase. DISCUSSION: Although using a drug as maintenance therapy that was not used in the induction regimen exposes patients to an agent with a different mechanism of action, evidence suggests that continued use of an agent present in the induction regimen as maintenance therapy enables the identification of patients most likely to benefit from maintenance treatment.

Optimization of treatment with interferon beta in multiple sclerosis. Usefulness of automatic system application criteria

Background. A software based tool has been developed (Optem) to allow automatize the recommendations of the Canadian Multiple Sclerosis Working Group for optimizing MS treatment in order to avoid subjective interpretation. METHODS: Treatment Optimization Recommendations (TORs) were applied to our database of patients treated with IFN beta1a IM. Patient data were assessed during year 1 for disease activity, and patients were assigned to 2 groups according to TOR: "change treatment" (CH) and "no change treatment" (NCH). These assessments were then compared to observed clinical outcomes for disease activity over the following years. RESULTS: We have data on 55 patients. The "change treatment" status was assigned to 22 patients, and "no change treatment" to 33 patients. The estimated sensitivity and specificity according to last visit status were 73.9% and 84.4%. During the following years, the Relapse Rate was always higher in the "change treatment" group than in the "no change treatment" group (5 y; CH: 0.7, NCH: 0.07; p < 0.001, 12 m - last visit; CH: 0.536, NCH: 0.34). We obtained the same results with the EDSS (4 y; CH: 3.53, NCH: 2.55, annual progression rate in 12 m - last visit; CH: 0.29, NCH: 0.13). CONCLUSION: Applying TOR at the first year of therapy allowed accurate prediction of continued disease activity in relapses and disability progression.