Development and validation of a bioanalytical method by LC-MS/MS for the quantification of the LAFIS 10 - an antimalarial candidate - and its pharmacokinetics first evaluation.

A rapid and highly sensitive method by LC-MS/MS was developed and validated for the quantification of an antimalarial candidate (LAFIS10) in rat plasma using dexamethasone as internal standard (IS). The chromatographic separation was performed with a Poroshell 120 EC-C18 column. The mobile phase consisted of water (A) and acetonitrile (B), both containing 10 m m of ammonium formate and 0.1% formic acid, delivered in the form of elution gradient. The LAFIS10 was monitored using an electrospray ionization interface operating in the positive mode in multiple reaction monitoring mode, monitoring the transitions 681.47 → 538.2 for LAFIS10 and 393.20 → 355.30 for the IS. The flow rate was 500 µL/min. The column temperature was kept at 40 °C and the injection volume was 2 µL. The lower limit of quantification was of 10 ng/mL and linearity between 10 and 1000 ng/mL was observed, with an R(2) > 0.99. The accuracy of the method was >90%. The relative standard deviations intra- and interday were <8.80 and <6.37%, respectively. The method showed sensitivity, linearity, precision, accuracy and selectivity required to quantify LAFIS 10 in preclinical pharmacokinetic studies according to criteria established by the US Food and Drug Administration and European Medicines Agency.

Validated HPLC method for determination of LASSBio-581, a new heterocyclic N-phenylpiperazine derivative, in rat plasma.

A rapid, simple and accurate high performance liquid chromatography (HPLC) method was developed and validated for the determination of LASSBio-581 (1-[1-(4-chloro-phenyl)-1H-[1,2,3]triazol-4-ylmethyl]-4-phenyl-piperazine) in rat plasma using ketoconazole as internal standard. Plasma samples were deproteinized with methanol. A good chromatographic separation was achieved using a reversed phase C18 column. Mobile phase consisting of sodium dihydrogen phosphate monohydrate (pH 4.5, 0.02 M) and methanol mixture (35:65, v/v) was used at a flow rate of 1.0 ml/min. The eluate was monitored using a UV detector at 248 nm. The retention times of LASSBio-581 and the internal standard were approximately 3.8 and 5.6 min, respectively. The calibration curves were linear over the concentration range of 0.25-8.0 microg/ml with correlation coefficients >0.99. The limit of quantitation was 0.25 microg/ml. The accuracy of the method was >90%. The intra-day relative standard deviation (R.S.D.) ranged from 6.15 to 10.52% at 0.4 microg/ml, 7.44 to 13.81% at 1.5 microg/ml and 6.10 to 13.94% at 6.0 microg/ml. The inter-day R.S.D. were 9.54, 8.42 and 8.25% at 0.4, 1.5 and 6.0 microg/ml, respectively. No interference from endogenous substances or metabolites were observed. The method has been used to measure plasma concentrations of LASSBio-581 in pharmacokinetic studies in rats.

Dopaminergic profile of new heterocyclic N-phenylpiperazine derivatives

Dopamine constitutes about 80 percent of the content of central catecholamines and has a crucial role in the etiology of several neuropsychiatric disorders, including Parkinson's disease, depression and schizophrenia. Several dopaminergic drugs are used to treat these pathologies, but many problems are attributed to these therapies. Within this context, the search for new more efficient dopaminergic agents with less adverse effects represents a vast research field. The aim of the present study was to report the structural design of two N-phenylpiperazine derivatives, compound 4: 1-[1-(4-chlorophenyl)-1H-4-pyrazolylmethyl]-4-phenylhexahydropyrazine and compound 5: 1-[1-(4-chlorophenyl)-1H-1,2,3-triazol-4-ylmethyl]-4-phenylhexahydropyrazine, planned to be dopamine ligands, and their dopaminergic action profile. The two compounds were assayed (dose range of 15-40 mg/kg) in three experimental models: 1) blockade of amphetamine (30 mg/kg, ip)-induced stereotypy in rats; 2) the catalepsy test in mice, and 3) apomorphine (1 mg/kg, ip)-induced hypothermia in mice. Both derivatives induced cataleptic behavior (40 mg/kg, ip) and a hypothermic response (30 mg/kg, ip) which was not prevented by haloperidol (0.5 mg/kg, ip). Compound 5 (30 mg/kg, ip) also presented a synergistic hypothermic effect with apomorphine (1 mg/kg, ip). Only compound 4 (30 mg/kg, ip) significantly blocked the amphetamine-induced stereotypy in rats. The N-phenylpiperazine derivatives 4 and 5 seem to have a peculiar profile of action on dopaminergic functions. On the basis of the results of catalepsy and amphetamine-induced stereotypy, the compounds demonstrated an inhibitory effect on dopaminergic behaviors. However, their hypothermic effect is compatible with the stimulation of dopaminergic function which seems not to be mediated by D2/D3 receptors

Dopaminergic profile of new heterocyclic N-phenylpiperazine derivatives.

Dopamine constitutes about 80% of the content of central catecholamines and has a crucial role in the etiology of several neuropsychiatric disorders, including Parkinson's disease, depression and schizophrenia. Several dopaminergic drugs are used to treat these pathologies, but many problems are attributed to these therapies. Within this context, the search for new more efficient dopaminergic agents with less adverse effects represents a vast research field. The aim of the present study was to report the structural design of two N-phenylpiperazine derivatives, compound 4: 1-[1-(4-chlorophenyl)-1H-4-pyrazolylmethyl]-4-phenylhexahydropyrazine and compound 5: 1-[1-(4-chlorophenyl)-1H-1,2,3-triazol-4-ylmethyl]-4-phenylhexahydropyrazine, planned to be dopamine ligands, and their dopaminergic action profile. The two compounds were assayed (dose range of 15-40 mg/kg) in three experimental models: 1) blockade of amphetamine (30 mg/kg, ip)-induced stereotypy in rats; 2) the catalepsy test in mice, and 3) apomorphine (1 mg/kg, ip)-induced hypothermia in mice. Both derivatives induced cataleptic behavior (40 mg/kg, ip) and a hypothermic response (30 mg/kg, ip) which was not prevented by haloperidol (0.5 mg/kg, ip). Compound 5 (30 mg/kg, ip) also presented a synergistic hypothermic effect with apomorphine (1 mg/kg, ip). Only compound 4 (30 mg/kg, ip) significantly blocked the amphetamine-induced stereotypy in rats. The N-phenylpiperazine derivatives 4 and 5 seem to have a peculiar profile of action on dopaminergic functions. On the basis of the results of catalepsy and amphetamine-induced stereotypy, the compounds demonstrated an inhibitory effect on dopaminergic behaviors. However, their hypothermic effect is compatible with the stimulation of dopaminergic function which seems not to be mediated by D2/D3 receptors.

The desire to be fashionable. Should we consider it a risk factor for infection in adolescents with acute leukaemia?

Three cases of skin infection, two with Pseudomonas aeruginosa and one with Staphylococcus aureus in three adolescents with acute leukaemia are described. In all cases the infection was clearly related to the latest fashion in shoes. This report underline the fact that factors related to everyday life and less frequently considered than those related to the underlying illness can also put increase the risk of developing severe infections in immunocompromised patients.

Changing epidemiologic pattern of chronic hepatitis C virus infection in Italian children.

OBJECTIVE: To evaluate the epidemiologic features of chronic hepatitis C virus (HCV) infection in children. STUDY DESIGN: All 106 children with chronic HCV infection consecutively observed in 3 Italian pediatric centers between 1991 and 1997 entered the study. RESULTS: Fifteen children had a history of non-A, non-B hepatitis, and 5 complained of nonspecific symptoms. The 86 remaining patients were free of symptoms and were recruited after HCV screening for intercurrent diseases, maternal infection, or other putative exposure; 39% (none of 30 children born after 1990) had received transfusions, whereas 44%, had a mother with HCV infection. Of the 47 infected mothers, 36% were or had been intravenous drug users, 15% had received transfusions, and 45% had no history of exposure. CONCLUSIONS: Children with chronic HCV infection are often free of symptoms, and thus HCV screening for putative risk has greatly increased the chances of diagnosis. Vertical transmission seems to now be the most common route of infection. Both current and past maternal intravenous drug abuse are risk factors for pediatric infection; however, in an area with relatively high prevalence of anti-HCV in the general population such as Italy, a consistent proportion of infectious mothers have no risk factors of HCV exposure.

Cervical lymphadenitis caused by nontuberculous mycobacteria in immunocompetent children: clinical and therapeutic experience.

BACKGROUND: Cervical lymphadenitis is a frequent manifestation of nontuberculous mycobacteria (NTM) infection in immunocompetent children. Surgical excision, the treatment of choice, is often incomplete and may be difficult. A medical approach could reduce treatment morbidity. METHODS: Systemic antibiotic therapy was administered to seven children for at least 6 months as treatment for cervical lymphadenitis due to NTM: rifabutin and clarithromycin in 4 cases; rifabutin, clarithromicyn, and ethambutol in 2 cases; rifabutin, amikacin, and cycloserine in 1 case. RESULTS: All patients, six followed for a mean of 3 years and one for 6 months, were initially seen with regression of local signs of infection without relapse. Toxicity, likely due to rifabutin, was represented by neutropenia in three patients and yellow skin pigmentation in one patient. CONCLUSIONS: Systemic antibiotic therapy was safe and effective in children with lymphadenitis due to NTM. This approach could represent a sound alternative or adjunct to surgery.

Vertical transmission of hepatitis C virus infection: usefulness of viremia detection in HIV-seronegative hepatitis C virus-seropositive mothers.

Seventy mother-newborn pairs were studied for hepatitis C viremia to evaluate the risk of vertical transmission of hepatitis C virus from human immunodeficiency virus-negative mothers. Forty-five mothers were hepatitis C virus-RNA positive: 4 to 45 children were positive at birth and during follow-up. The level of viremia plays an important role in vertical transmission.

Treatment of visceral leishmaniasis in children with liposomal amphotericin B.

We used liposomal amphotericin B as first-choice treatment of visceral leishmaniasis in 106 immunocompetent children who acquired the infection in a temperate region of southern Europe (Italy) where Leishmania infantum visceral leishmaniasis is endemic. The aim of the study was to identify the minimum total dose of liposomal amphotericin B needed to cure the infection in children and reduce the period of hospitalization. We conclude that the optimal regimen in immunocompetent children with L. infantum visceral leishmaniasis to be a total dose of 18 mg/kg of liposomal amphotericin B (3 mg/kg per day for 5 days, followed by 3 mg/kg administered as an outpatient regimen on day 10).

Broviac catheter-related bacteraemias due to unusual pathogens in children with cancer: case reports with literature review.

Among 102 episodes of intravenous catheter related bacteraemias documented between January 1989 and July 1996 in children receiving antineoplastic chemotherapy or bone marrow transplantation at G. Gaslini Children's Hospital, Genoa, Italy, were identified seven episodes due to unusual pathogens: Bacillus circulans, Bacillus licheniformis, Brevibacterium casei, Flavimonas oryzihabitans, Porphyromonas asaccharolytica, Comamonas acidovorans and Agrobacterium radiobacter. Susceptibility to different antibiotics of all strains are reported. In all cases catheter removal was required for culture negativization. All episodes were diagnosed in absence of granulocytopenia.

Lysis of a right atrial thrombus of more than a week's duration by high dose urokinase in a one-year-old child.

The case of a one-year-old child in whom a large catheter-related right atrial thrombus of more than a week's duration was dissolved by urokinase is presented. After one week of unsuccessful heparin treatment, urokinase, via a central venous catheter, was added at a dose of 1500 IU/kg/h. Urokinase was subsequently increased by 1000 U/kg/h every day up to a maximum of 4500 IU/kg/h on the basis of thrombus size reduction as assessed by daily cross-sectional echocardiography. One week later the thrombus was almost completely dissolved. No major bleeding occurred. Warfarin was given for the next three months and the international normalized ratio (INR) was maintanied between 2 and 3. At the end of warfarin treatment echocardiography was negative for right atrial thrombosis. This case suggests that local high dose urokinase therapy can be safely and successfully used to dissolve large right atrial thromboses of more than a week's duration.

[Sepsis related to a permanent central venous catheter in children with neoplastic disease: practical implications of a continuous surveillance of the etiology]. / Sepsi correlate a catetere venoso centrale a permanenza in bambini affetti da malattia neoplastica: implicazioni pratiche di una sorveglianza continua dell'eziologia.

Indwelling central venous catheter-related bacteremias are an important complication in patients with cancer. In general they are due to Staphylococcus aureus and Candida, while bacteremias caused by Gram-negatives are less common and often related to infusate contaminans. We describe a survey of etiological surveillance of Broviac catheter-related infections at G. Gaslini Children's Hospital of Genoa, Italy. In the period 1989-1992 an increase of Broviac catheter-related bacteremias due to Gram-negatives was demonstrated as compared with previous years (1985-1988). At home parental management was suspected as an important risk factor, since this complication was frequently due to infusate contaminants and no epidemic cluster or positive surveillance culture was observed in the Hospital. Therefore at home management was changed, especially regarding heparin storage. The subsequent, prospective follow-up from July 1993 to December 1995 showed a significant decrease in catheter-related bacteremias due to Gram-negatives (P = 0.003, chi-square test). In conclusion, a strict control on at home catheter management procedures must be maintained in order to reduce the risk of indwelling central venous catheter-related infections in children with cancer.

Early efficacy of liposomal amphotericin B in the treatment of visceral leishmaniasis.

The rapidity and efficacy of a short course of liposomal amphotericin B was evaluated in 29 children affected by visceral leishmaniasis (Leishmania infantum). Their overall health status was assessed using the prognostic inflammatory and nutritional index (PINI), and their haematological status by the reticulocyte count and haemoglobin blood levels. All these quantities were measured on day 0, and 3 and 10 d after starting therapy. A significant decrease of inflammatory signs, associated with an improved reticulocyte count, was recorded after 3 d of therapy. A significant increase of haemoglobin levels was also observed 10 d after the start of treatment. The early reduction of inflammatory signs and the improvement of bone marrow function in most patients confirmed the validity of amphotericin B therapy. The PINI score is helpful in assessing the severity of visceral leishmaniasis and the follow-up of its treatment.

Low CD4 lymphocyte count in a patient with P. carinii pneumonia after autologous bone marrow transplantation.

Authors report a case of P. carinii pneumonia in a child with 5% CD4 lymphocytes (absolute number 5/microliters) after autologous bone marrow transplantation followed by pulmonary irradiation. Serial evaluation of CD4 lymphocyte count or percentage or, at least, detection of significant and persistent lymphopenia could be useful for detecting a high risk of developing P. carinii pneumonia.