Combined Application of Antisense Oligomers to Control Transcription Factors of Candida albicans Biofilm Formation

Antisense oligomers (ASOs) have been little exploited to control determinants of Candida albicans virulence. Biofilm formation is an important virulence factor of C. albicans, that is regulated by a complex network of transcription factors (such as EFG1, BRG1 and ROB1). Thus, the main goal of this work was to project ASOs, based on the 2'-OMethyl chemical modification, to target BRG1 and ROB1 mRNA and to validate its application either alone or in combination with the EFG1 mRNA target, to reduce C. albicans biofilm formation. The ability of ASOs to control gene expression was evaluate by qRT-PCR. The effect on biofilm formation was determined by the total biomass quantification, and simultaneously the carbohydrates and proteins reduction on extracellular matrix. It was verified that all the oligomers were able to reduce the levels of gene expression and the ability of C. albicans to form biofilms. Furthermore, the combined application of the cocktail of ASOs enhances the inhibition of C. albicans biofilm formation, minimizing biofilm thickness by reducing the quantity of matrix content (protein and carbohydrate). So, our work confirms that ASOs are useful tools for research and therapeutic development on the control of Candida species biofilm formation.

Effect of phage vB_EcoM_FJ1 on the reduction of ETEC O9:H9 infection in a neonatal pig cell line

Enterotoxigenic Escherichia coli (ETEC) colonizes the intestine of young pigs causing severe diarrhoea and consequently bringing high production costs. The rise of antibiotic selective pressure together with ongoing limitations on their use, demands new strategies to tackle this pathology. The pertinence of using bacteriophages as an alternative is being explored, and in this work, the efficacy of phage vB_EcoM_FJ1 (FJ1) in reducing the load of ETEC EC43-Ph (serotype O9:H9 expressing the enterotoxin STa and two adhesins F5 and F41) was assessed. Foreseeing the oral application on piglets, FJ1 was encapsulated on calcium carbonate and alginate microparticles, thus preventing phage release under adverse conditions of the simulated gastric fluid (pH 3.0) and allowing phage availability in simulated intestinal fluid (pH 6.5). A single dose of encapsulated FJ1, provided to IPEC-1 cultured cells (from intestinal epithelium of piglets) previously infected by EC43, provided bacterial reductions of about 99.9% after 6 h. Although bacteriophage-insensitive mutants (BIMs) have emerged from treatment, the consequent fitness costs associated with this new phenotype were demonstrated, comparatively to the originating strain. The higher competence of the pig complement system to decrease BIMs' viability, the lower level of colonization of IPEC-1 cells observed with these mutants, and the increased survival rates and health index recorded in infected Galleria mellonella larvae supported this observation. Most of all, FJ1 established a proof-of-concept of the efficiency of phages to fight against ETEC in piglet intestinal cells.

Simulated vaginal fluid: Candida resistant strains' biofilm characterization and vapor phase of essential oil effect

INTRODUCTION

Vulvovaginal candidiasis is a disease that affects millions of women worldwide. Oral formulations, topical creams or ointments are the conventional dosage forms, with an increase in drug administration through vaginal via. The use of simulated biological fluids (e.g. vaginal fluid) in the evaluation of antifungal therapies may better mimic the real biological environments and therefore provide a better understanding of the behavior of the antifungal.

METHODS

The main objective of this work was to compare planktonic growth and biofilm formation of Candida species, on common growth medium, Sabouraud Dextrose Broth (SDB) and on vaginal simulation conditions, Simulated Vaginal Fluid (SVF), through the optical density determination, colony-forming units and scanning electron microscopy. In addition, under the same conditions this study also evaluated the ability of vapor phase of oregano and white thyme essential oils (VP-EOs), potential alternative treatment, to inhibit biofilm formation and to destroy mature biofilms of vaginal isolates, through the colony-forming units determination.

RESULTS

Candida isolates maintained the same biofilm formation capacity and morphology in both media (SVF and SDB). Furthermore, the results obtained in this work related with VP-EOs effect agree with results acquired, previously, with SDB. This means that the effect of VP-EOs is not affected by the SVF medium, and that this fluid allows the dissolution of the volatile and bioactive compounds.

CONCLUSIONS

These results can predict the in vivo behavior, suggesting a potential effective application of VP-EOs as prophylactic or therapeutic treatment for biofilm-related vulvovaginal candidiasis.

Antisense locked nucleic acid gapmers to control Candida albicans filamentation

Whereas locked nucleic acid (LNA) has been extensively used to control gene expression, it has never been exploited to control Candida virulence genes. Thus, the main goal of this work was to compare the efficacy of five different LNA-based antisense oligonucleotides (ASO) with respect to the ability to control EFG1 gene expression, to modulate filamentation and to reduce C. albicans virulence. In vitro, all LNA-ASOs were able to significantly reduce C. albicans filamentation and to control EFG1 gene expression. Using the in vivo Galleria mellonella model, important differences among the five LNA-ASOs were revealed in terms of C. albicans virulence reduction. The inclusion of PS-linkage and palmitoyl-2'-amino-LNA chemical modification in these five LNA gapmers proved to be the most promising combination, increasing the survival of G. mellonella by 40%. Our work confirms that LNA-ASOs are useful tools for research and therapeutic development in the candidiasis field.

Portuguese honeys as antimicrobial agents against Candida species

BACKGROUND AND AIM

Honey has been recognized worldwide for its antioxidant, anti-tumor, anti-inflammatory and antimicrobial properties. Among them, the antifungal properties associated to honey make it an attractive alternative treatment for Candida-associated infections, particularly for topical application to the mucous membranes and skin. In this sense, the main purpose of this work was to evaluate physicochemical properties of five Portuguese honeys and Manuka honey (an Australian honey with well recognized medical proprieties, used as control) and to evaluate the antifungal activity in Candida species planktonic and biofilm assays.

EXPERIMENTAL PROCEDURE

Pollen analysis, pH determination, color, concentration of protein and methylglyoxal, conductivity, total phenolics and flavonoids, hydrogen peroxide concentration, and characterization by differential scanning calorimetry in honey samples were determined. Additionally, the effect of honeys on planktonic growth of Candida was initially evaluated by determination of the minimum inhibitory concentrations. Then, the same effect of those honeys was evaluated in biofilms, by Colony Forming Units enumeration.

RESULTS AND CONCLUSION

It has been shown that Portuguese heather (Erica cinereal) honey presented the most similar physicochemical properties to manuka honey (specially phenolic and flavonoids contents). The five Portuguese honeys under study, presented in general a potent activity against planktonic multi-resistant yeast pathogens (several clinical isolates and reference strains of Candida species) and S. aureus and P. aeruginosa bacteria cultures. Additionally, it was also concluded that Portuguese heather honey (50% and 75% (w/v)) can also act as a good Candida species biofilm reducer, namely for C. tropicalis.

Satureja montana L. and Origanum majorana L. Decoctions: Antimicrobial Activity, Mode of Action and Phenolic Characterization

Medicinal and aromatic plants are known to have a wide range of uses and health benefits, and should be exploited for their bioactivity. Here we evaluated the antimicrobial activity of decoctions of Satureja montana L. and Origanum majorana L. against Gram-positive and Gram-negative bacteria and Candida spp. as well as their mechanism of action and phenolic characterization. The Satureja montana and Origanum majorana extracts were effective against a broad set of species, including the Gram-positive Staphylococcus aureus, Enterococcus faecalis, and Streptococcus dysgalactiae and the Gram-negative Klebsiella pneumoniae and Pseudomonas aeruginosa. Both extracts were found to have rosmarinic acid as the main phenolic compound and to exert their antimicrobial activity at the level of the cell membrane. Membrane perturbations by the extracts impaired cell membrane integrity only a few hours after exposure. This study confirms the bioactive potential of Satureja montana and Origanum majorana decoctions, and supports the development of novel formulations with wide antimicrobial properties based on these medicinal and aromatic herbs.

Candida spp./Bacteria Mixed Biofilms

The ability to form biofilms is a common feature of microorganisms, such as bacteria or fungi. These consortiums can colonize a variety of surfaces, such as host tissues, dentures, and catheters, resulting in infections highly resistant to drugs, when compared with their planktonic counterparts. This refractory effect is particularly critical in polymicrobial biofilms involving both fungi and bacteria. This review emphasizes Candida spp.-bacteria biofilms, the epidemiology of this community, the challenges in the eradication of such biofilms, and the most relevant treatments.

Application of 2'-OMethylRNA' Antisense Oligomer to Control Candida albicans EFG1 Virulence Determinant

Antisense oligomers and their analogs have been successfully utilized to silence gene expression for the treatment of many human diseases; however, the control of yeast’s virulence determinants has never been exploited before. In this sense, this work is based on the key hypothesis that if a pathogen’s genetic sequence is a determinant of virulence, it will be possible to synthesize a nucleic acid mimic based on antisense therapy (AST) that will bind to the mRNA produced, blocking its translation into protein and, consequently, reducing the pathogen virulence phenotype. EFG1 is an important determinant of virulence that is involved in the regulation of the Candida albicans switch from yeast to filamentous form. Thus, our main goal was to design and synthesize an antisense oligonucleotide (ASO) targeting the EFG1 mRNA and to validate its in vitro applicability. The results show that the anti-EFG1 2′-OMethylRNA (2′OMe) oligomer was able to significantly reduce the levels of EFG1 gene expression and of Efg1p protein translation (both approximately 60%), as well as effectively prevent filamentation of C. albicans cells (by 80%). Moreover, it was verified that anti-EFG1 2′OMe keeps the efficacy in different simulated human body fluids. Undeniably, this work provides potentially valuable information for future research into the management of Candida infections, regarding the development of a credible and alternative method to control C. albicans infections, based on AST methodology.

Susceptibility of Candida glabrata biofilms to echinocandins: alterations in the matrix composition

Candidiases are the most recurrent fungal infections, especially among immunosuppressed patients. Although Candida albicans is still the most widespread isolated species, non-Candida albicans Candida species have been increasing. The goal of this work was to determine the susceptibility of C. glabrata biofilms to echinocandins and to evaluate their effect on the biofilm matrix composition, comparing the results with other Candida species. Drug susceptibilities were assessed through the determination of minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC) and minimum biofilm eradication concentration (MBEC) of caspofungin (Csf) and micafugin (Mcf). The β-1,3 glucans content of the matrices was assessed after contact with the drugs. The data suggest that, generally, after contact with echinocandins, the concentration of β-1,3 glucans increased. These adjustments in the matrix composition of C. glabrata biofilms and the chemical differences between Csf and Mcf, seem responsible and may determine the effectivity of the drug responses.

Lactobacillus crispatus represses vaginolysin expression by BV associated Gardnerella vaginalis and reduces cell cytotoxicity

Using a chemically-defined medium simulating genital tract secretions, we have shown that pre-adhering Lactobacillus crispatus to Hela epithelial cells reduced cytotoxicity caused by Gardnerella vaginalis. This effect was associated to the expression of vaginolysin and was specific to L. crispatus interference, as other vaginal facultative anaerobes had no protective effect.

The Effectiveness of Voriconazole in Therapy of Candida glabrata's Biofilms Oral Infections and Its Influence on the Matrix Composition and Gene Expression

Candida glabrata is one of most prevalent yeast in fungal infections, especially in immunocompromised patients. Its azole resistance results in a low therapeutic response, particularly when associated with biofilms. The main goal of this work was to study the effectiveness of voriconazole (Vcz) against C. glabrata biofilms oral pathologies, as esophageal or oropharyngeal candidiasis. Antifungal susceptibilities were determined in pre-formed 24-h-biofilms and ERG genes expression was determined by qRT-PCR. Protein quantification was performed using BCA^® Kit, carbohydrate was estimated according to the Dubois assay and β-1,3 glucans concentration were determined using Glucatell^® kit. Finally, ergosterol, Vcz, and fluconazole (Flu) concentrations within the biofilm matrices were determined by RP-HPLC. Results showed that C. glabrata biofilms were more susceptible to Vcz than to Flu and that ERG genes expression evidenced an overexpression of the three ERG genes in the presence of both azoles. The matrix content presented a remarked decrease in proteins and an increase in carbohydrates, namely β-1,3 glucans. Ergosterol was successfully detected and quantified in the biofilm matrices, with no differences in all the considered conditions. Vcz demonstrated better diffusion through the biofilms and better cell penetration capacities, than Flu, indicating that the structure of the drug molecule fully influences its dissemination through the biofilm matrices. This work showed that Vcz is notably more effective than Flu for the treatment of resistant C. glabrata oral biofilms, which demonstrates a clinical relevance in its future use for the treatment of oropharyngeal/esophageal candidiasis caused by this species.

Candida Species Biofilms' Antifungal Resistance

Candida infections (candidiasis) are the most prevalent opportunistic fungal infection on humans and, as such, a major public health problem. In recent decades, candidiasis has been associated to Candida species other than Candida albicans. Moreover, biofilms have been considered the most prevalent growth form of Candida cells and a strong causative agent of the intensification of antifungal resistance. As yet, no specific resistance factor has been identified as the sole responsible for the increased recalcitrance to antifungal agents exhibited by biofilms. Instead, biofilm antifungal resistance is a complex multifactorial phenomenon, which still remains to be fully elucidated and understood. The different mechanisms, which may be responsible for the intrinsic resistance of Candida species biofilms, include the high density of cells within the biofilm, the growth and nutrient limitation, the effects of the biofilm matrix, the presence of persister cells, the antifungal resistance gene expression and the increase of sterols on the membrane of biofilm cells. Thus, this review intends to provide information on the recent advances about Candida species biofilm antifungal resistance and its implication on intensification of the candidiasis.

Novel strategies to fight Candida species infection

In recent years, there has been a significant increase in the incidence of human fungal infections. The increase in cases of infection caused by Candida species, and the consequent excessive use of antimicrobials, has favored the emergence of resistance to conventional antifungal agents over the past decades. Consequently, Candida infections morbidity and mortality are also increasing. Therefore, new approaches are needed to improve the outcome of patients suffering from Candida infections, because it seems unlikely that the established standard treatments will drastically lower the morbidity of mucocutaneous Candida infections and the high mortality associated with invasive candidiasis. This review aims to present the last advances in the traditional antifungal therapy, and present an overview of novel strategies that are being explored for the treatment of Candida infections, with a special focus on combined antifungal agents, antifungal therapies with alternative compounds (plant extracts and essential oils), adjuvant immunotherapy, photodynamic therapy and laser therapy.

Feed optimization in fed-batch culture

Fed-batch processes are a current preference for the production of recombinant proteins in mammalian cells. The use of nutrient feeding prevents the depletion of important medium components and results in improved culture longevity and high cell and product yields. To take maximum advantage of these effects, it is important to optimize the fed-batch process for each application. In this chapter, a simple strategy for fed-batch optimization is described, consisting of the development of a feed medium based on spent media analysis and the establishment of a feeding strategy that consists of adding variable volumes of feed media at specific intervals, after off-line measurement of the concentration of a reference nutrient.

Evaluation of solid and porous microcarriers for cell growth and production of recombinant proteins

Microcarrier technology opened new perspectives for anchorage-dependent cell culture, by providing increased surface areas for cell adhesion and proliferation, and therefore improving both cell and product yields obtained in these cultures. The establishment of a successful microcarrier culture depends on many factors, such as the type of microcarrier, the cells, and the culture conditions. In this chapter, the basic steps required for the evaluation and optimization of a microcarrier culture for the purpose of production of recombinant proteins are described, for both solid and porous microcarriers.

The impact of microcarrier culture optimization on the glycosylation profile of a monoclonal antibody

Microcarriers are widely used for the large-scale culture of attachment-dependent cells with increased cell densities and, ultimately, higher product yield. In these processes, the specific culture conditions can affect the quality of the product, which is closely related to its glycosylation pattern. Furthermore, the lack of studies in the area reinforces the need to better understand the effects of microcarrier culture in product glycosylation. Consequently, in this work, the glycosylation profile of a monoclonal antibody (mAb) produced by adherent CHO-K1 cells grown in Cytodex 3 was evaluated under different conditions, and compared to that obtained of typical adherent cultures. It was found that microcarrier cultures result in a glycosylation profile with different characteristics from T-flask cultures, with a general increase in galactosylation and decrease in fucosylation levels, both with a potentially positive impact on mAb activity. Sialylation also varied but without a general tendency. This study then showed that the specific culture conditions used in microcarrier culture influence the mAb glycan profile, and each functional element (galactose, core fucose, sialic acid) is independently affected by these conditions. In particular, great reductions of fucosylation (from 79 to 55%) were obtained when using half volume at inoculation, and notable decreases in sialylation (from 23 to 2%) and glycoform heterogeneity (from 20 to 11 glycoforms) were observed for shake flask culture, potentially associated with the improved cell densities achieved in these culture vessels.

Glycosylation: impact, control and improvement during therapeutic protein production

The emergence of the biopharmaceutical industry represented a major revolution for modern medicine, through the development of recombinant therapeutic proteins that brought new hope for many patients with previously untreatable diseases. There is a ever-growing demand for these therapeutics that forces a constant technological evolution to increase product yields while simultaneously reducing costs. However, the process changes made for this purpose may also affect the quality of the product, a factor that was initially overlooked but which is now a major focus of concern. Of the many properties determining product quality, glycosylation is regarded as one of the most important, influencing, for example, the biological activity, serum half-life and immunogenicity of the protein. Consequently, monitoring and control of glycosylation is now critical in biopharmaceutical manufacturing and a requirement of regulatory agencies. A rapid evolution is being observed in this context, concerning the influence of glycosylation in the efficacy of different therapeutic proteins, the impact on glycosylation of a diversity of parameters/processes involved in therapeutic protein production, the analytical methodologies employed for glycosylation monitoring and control, as well as strategies that are being explored to use this property to improve therapeutic protein efficacy (glycoengineering). This work reviews the main findings on these subjects, providing an up-to-date source of information to support further studies.

Fracturing of Revision of a Cobalt-chrome Femoral Head after Fracturing of a Ceramic Femoral Head, with Diffuse Metallosis. Case Report

We presente a case of a fracture of a cobalt-chrome femoral head after revision of a hip total prosthesis with ceramic femoral head fracture. During surgery we found the cobalt- chrome femoral head fracture, wear of the polyethylene and massive metallosis in muscular and cartilaginous tissue. Both femoral stem and acetabular cup were stable and without apparent wearing. After surgical debridement, we promoted the substitution of the femoral head and the acetabular polyethylene by similar ones. After 12 months of follow- up, the patient has no pain complaints, function limit or systemic signs associated with malign metallosis.

Traumatic rupture of the tibialis anterior tendon: A case report

Objective: The autors report a case of a traumatic rupture of the tibialis anterior tendon (TTA) that was early diagnosed and treated in the emergency service. This is a rare clinical entity with few cases reported in the literature. Case report: A 66-year old female presented at the emergency service complaining about pain at the anterior aspect of her ankle and inability to walk normally, after a fall. Physical examination revealed clinical signs for TTA rupture, which was later confirmed by ultrasound. Surgical treatment was performed immediately – the tendon was anchored into the medial cuneiform with a soft tissue-to-bone anchor. The follow-up revealed good functional result. Conclusion: Physical examination and a high index of suspicion are important when facing a patient who had sustained an ankle trauma. The TTA rupture is a diagnosis to consider because unrecognized ruptures led to important functional deficits and poor functional results.

Espondilodiscite atípica

As infecções por Staphylococcus coagulase-negativo correspondem a uma pequena percentagem do total das espondilodiscites piogênicas, estando associados a estados imunocomprometidos. Apresentamos o caso clínico de um homem de 58 anos, com uma espondilodiscite L1-L2, por um micro-organismo bastante atípico, o S. hominis. A resolução da patologia só foi possível após duas cirurgias e terapia com antibióticos específicos.

Comparison of commercial serum-free media for CHO-K1 cell growth and monoclonal antibody production

The selection of a serum-free medium for a particular process of production using mammalian cells is a critical step for its success. In this study, seven commercially available serum-free media (EX-CELL, ISF-I, CD CHO, CDM4CHO, CHO-III-A, Octomed and HybridoMed) were evaluated and compared for cell growth and monoclonal antibody (mAb) production of a transfected CHO-K1 cell line. In the conditions assayed, EX-CELL and particularly CDM4CHO are the most recommended media for extended biopharmaceutical processes, on account of inducing superior levels of cell proliferation and mAb production, accentuated by a tendency to improve over time. Furthermore, the less positive results obtained with some media emphasize the importance and the impact of the correct medium selection.

Evaluation of the OSCAR system for the production of monoclonal antibodies by CHO-K1 cells

Biopharmaceutical production of complex recombinant protein therapeutics currently relies on mammalian cells. The development of high-yielding stable cell lines requires processes of transfection, selection and adaptation. With several technologies available, selection has been most frequently based on dihydrofolate reductase or glutamine synthetase systems, which can be very time-consuming. Due to the pressure to reduce development costs and speed up time to market, new technologies are emerging, as the promising OSCAR expression system that could provide more rapid development of high-yielding stable cell lines than the traditional systems. However, further evaluation of its application in a wider range of cell types and media is still necessary. In this study, application of OSCAR for the transfection of a CHO-K1 cell line with a monoclonal antibody was evaluated. OSCAR was reasonably fast and simple, without negative impact on cell growth characteristics. However, minigene selection was critical, with only pDWM128 working for the cell line assessed. Initial relatively high levels of production decreased significantly in the first few weeks of passing, remaining relatively stable although with low yield thereafter. The results suggest that more work is required to develop methodologies and prove that OSCAR has significant value to the bioproduction industry.

SPONTANEOUS RESOLUTION OF PSEUDOANEURYSM OF AN ILIAC ARTERY BRANCH IN A MULTIPLE TRAUMA PATIENT WITH PELVIC FRACTURE: CLINICAL CASE

In patients who have been the victims of high-energy trauma, severe pelvic injury should always be suspected. Most of these fractures are stable and respond well to conservative treatment. Pelvic fractures constitute 3% of all skeletal fractures and are associated with high-energy trauma. They are potentially serious injuries with significant mortality and large numbers of associated lesions. There are fundamentally three sources of bleeding in pelvic fractures: arterial, venous and through the bone ends of the fracture. Arterial bleeding is more associated with hemodynamic instability. In such cases, both early external fixation of the pelvic fracture and angiography with selective embolization of the bleeding vessels are effective methods for achieving hemostasis. Aneurysms of iliac artery branches are rare and are mostly pseudoaneurysm relating to the traumatic event. The natural history of pseudoaneurysms is unknown because of their rarity, but if they rupture, the mortality rate is high. We report a case of spontaneous thrombosis of a pseudoaneurysm of a branch of the right iliac artery.

Tuberculosis in renal transplants in Rio de Janeiro

Retrospective analysis of 982 renal transplants over 21 years (1981 to 2002) sought to evaluate the prevalence of tuberculosis (TB). This analysis included 74 patients: 30 with a past TB history, who had INH prophylaxis since the beginning of immunosuppression, and 44 who only became TB infected after receiving transplants. The diagnosis of TB was made by a compatible medical situation with bacteriological/histological confirmation, which when not possible, underwent a therapeutic test occur. The average time for the illness to surge was 3 years. The mortality rate was 34.9% (15/44). Patients with hepatitis C were more affected. Among those who used INH prophylaxis only one contracted TB, showing that the drug displayed a protection rate of 96.6% (29/30).

[The evaluation of the tolerance and nephrotoxicity of pentavalent antimony administered in a dose of 40 mg Sb V/kg/day, 12/12 hr, for 30 days in the mucocutaneous form of leishmaniasis]

The renal function of eleven patients with mucocutaneous leishmaniasis was analyzed in a prospective study realized at the School Hospital of University of Brasília. The patients were treated with doses of 40 mg/kg/day of pentavalent antimony (Sb V), in a continuous scheme during thirty days. In this study three patients were excluded, one patient with reversible renal failure and two patients with hepatic and cardiac malfunctions. In the other eight patients, severe nephrotoxic effects were observed, like reduction of glomerular filtration rate, reduction of the urinary concentration capacity, evaluated by a sixteen hours hydric fasting and an increase of sodium fractional excretion. An increase in the number of leucocytes and cylinders were observed at the urinary sediment exam. Finally, the results shows that the treatment with pentavalent antimony in doses of 40 mg Sb/kg/day was less tolerated on account of its renal toxic effects. This scheme seems not be superior than the currently preconized scheme of 20 mg of Sb V/kg/day during 30 days.

Concentration of electrolytes in the sweat of malnourished children

The sweat test was performed by the method of Gibson and Cooke on 36 children with second and third degree malnutrition, aged from 2 months to 4 years. The results were compared with those from 32 healthy, well nourished controls in the same age range. Determinations were made of sodium and chloride concentrations, chloride/sodium ratio, and the sum of the concentrations of the two electrolytes in each sample. The malnourished children were found to have higher sodium and chloride concentrations than the well nourished ones. None of the normal or malnourished children had a sweat chloride value greater than 60 mmol/l; chloride values within a suspicious range (between 40 and 60 mmol/l) were found in two malnourished children. Two well nourished controls and six malnourished children showed suspicious sweat sodium concentrations; in one child with third degree malnutrition the sodium content was greater than 60 mmol/l. In all results in the suspicious range, or greater than 60 mmol/l, the chloride/sodium ratio was less than 1, and the sum of the two electrolytes was below 140 mmol/l. Based on these results, we conclude that malnourished children have raised sweat sodium and chloride concentrations when compared with well nourished children. The electrolyte values for most of them are not in a suspicious range or consistent with a diagnosis of cystic fibrosis. Unlike that found in cystic fibrosis, the sodium/chloride ratio in our subjects was less than 1 and the sum of both electrolytes never exceeded 140 mmol/l.

Six-month isoniazid-rifampin treatment for pulmonary tuberculosis in children

One hundred and seventeen children with pulmonary tuberculosis underwent treatment with a 6-month daily regimen of rifampin (15 mg/kg/day) and isoniazid (10 mg/kg/day). The criteria for the diagnosis of pulmonary tuberculosis were (1) clinical symptoms and signs in 93 children (79%), (2) history of direct contact with an adult with tuberculosis in 106 children (91%), (3) tuberculin reaction of 5 mm or more, without previous bacillus Calmette-Guérin (BCG), in 45 children (38%), (4) suggestive radiologic alterations in all patients, and (5) positive bacteriology or histology in four patients (3%). The treatment was completed by 97 children (83%). The mean weight gain during therapy was 2,145 g. There was an excellent clinicoradiologic response to the treatment, and improvement in chest roentgenograms was observed in all patients at the end of therapy. No relapses occurred among the patients followed for an average of 21.4 months. This study indicates that the treatment of primary pulmonary tuberculosis in children with a combination of rifampin and isoniazid daily for 6 months is efficacious and does not result in any relapse.