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Machado-Joseph disease, also known as spinocerebellar ataxia type 3, is the most common of the dominantly inherited ataxias worldwide and is characterized by mutant ataxin-3 misfolding, intracellular accumulation of aggregates and neuronal degeneration. Here we investigated the implication of autophagy, the major pathway for organelle and protein turnover, in the accumulation of mutant ataxin-3 aggregates and neurodegeneration found in Machado-Joseph disease and we assessed whether specific stimulation of this pathway could mitigate the disease. Using tissue from patients with Machado-Joseph disease, transgenic mice and a lentiviral-based rat model, we found an abnormal expression of endogenous autophagic markers, accumulation of autophagosomes and decreased levels of beclin-1, a crucial protein in the early nucleation step of autophagy. Lentiviral vector-mediated overexpression of beclin-1 led to stimulation of autophagic flux, mutant ataxin-3 clearance and overall neuroprotective effects in neuronal cultures and in a lentiviral-based rat model of Machado-Joseph disease. These data demonstrate that autophagy is a key degradation pathway, with beclin-1 playing a significant role in alleviating Machado-Joseph disease pathogenesis. [ABSTRACT FROM AUTHOR]

Background and Objective: Continuous positive airway pressure (CPAP) in the treatment of severe obstructive sleep apnoea (OSA) can be used in fixed CPAP or auto-adjusted (APAP) mode. The aim of this prospective randomized controlled clinical study was to evaluate the 3 month-efficacy of CPAP used either in fixed CPAP or APAP mode., Methods: Eight hundred one patients with severe OSA were included in twenty-two French centres. After 7 days during which all patients were treated with APAP to determine the effective pressure level and its variability, 353 and 351 patients were respectively randomized in the fixed CPAP group and APAP group. After 3 months of treatment, 308 patients in each group were analysed., Results: There was no difference between the two groups in terms of efficacy whatever the level of efficient pressure and pressure variability (p = 0.41). Exactly, 219 of 308 patients (71.1%) in the fixed CPAP group and 212 of 308 (68.8%) in the APAP group (p = 0.49) demonstrated residual apnoea hypopnoea index (AHI) <10/h and Epworth Score <11. Tolerance and adherence were also identical with a similar effect on quality of life and blood pressure evaluation., Conclusion: The two CPAP modes, fixed CPAP and APAP, were equally effective and tolerated in severe OSA patients., (© 2023 Asian Pacific Society of Respirology.)

Objective: To study the profile of patients with obstructive sleep apnoea syndrome (OSAS) and laryngopharyngeal reflux (LPR) at the hypopharyngeal-oesophageal multichannel intraluminal impedance-pH monitoring (HEMII-pH) and to compare their reflux findings with LPR patients without OSAS., Design: Prospective controlled study., Methods: Patients with LPR and OSAS were prospectively recruited from August 2019 to June 2020. The profile of hypopharyngeal reflux events (HREs) of patients was studied through a breakdown of the HEMII-pH findings over the 24 hours of testing. Reflux symptom score (RSS), and gastrointestinal and HEMII-pH outcomes were compared between LPR patients and patients with LPR and OSAS. Multivariate analysis was used to study the relationship between reflux data and the following sleep outcomes: Apnea Hypopnea Index, Epworth Sleepiness Scale (ESS) and paradoxical sleep data., Results: A total of 89 patients completed the study. There were 45 patients with LPR and 44 subjects with both OSAS and LPR. The numbers of upright and daytime HREs and the otolaryngological RSS were significantly higher in patients with LPR compared with those with OSAS and LPR. There was a significant positive association between RSS quality-of-life score and ESS (P = .001). The occurrence of HREs in the evening was associated with higher ESS (P = .015). Patients with OSAS, LPR and GERD had higher number of nocturnal HREs compared with those without GERD (P = .001)., Conclusion: The presence of OSAS in LPR patients is associated with less severe HEMII-pH and ear, nose and throat symptoms. There may have different OSAS patient profiles according to the occurrence of GERD., (© 2021 John Wiley & Sons Ltd.)

Alpha-synuclein (α-syn) and leucine-rich repeat kinase 2 (LRRK2) play crucial roles in Parkinson's disease (PD). They may functionally interact to induce the degeneration of dopaminergic (DA) neurons via mechanisms that are not yet fully understood. We previously showed that the C-terminal portion of LRRK2 (ΔLRRK2) with the G2019S mutation (ΔLRRK2 G2019S ) was sufficient to induce neurodegeneration of DA neurons in vivo, suggesting that mutated LRRK2 induces neurotoxicity through mechanisms that are (i) independent of the N-terminal domains and (ii) "cell-autonomous". Here, we explored whether ΔLRRK2 G2019S could modify α-syn toxicity through these two mechanisms. We used a co-transduction approach in rats with AAV vectors encoding ΔLRRK2 G2019S or its "dead" kinase form, ΔLRRK2 DK , and human α-syn with the A53T mutation (AAV-α-syn A53T ). Behavioral and histological evaluations were performed at 6- and 15-weeks post-injection. Results showed that neither form of ΔLRRK2 alone induced the degeneration of neurons at these post-injection time points. By contrast, injection of AAV-α-syn A53T alone resulted in motor signs and degeneration of DA neurons. Co-injection of AAV-α-syn A53T with AAV-ΔLRRK2 G2019S induced DA neuron degeneration that was significantly higher than that induced by AAV-α-syn A53T alone or with AAV-ΔLRRK2 DK . Thus, mutated α-syn neurotoxicity can be enhanced by the C-terminal domain of LRRK2 G2019 alone , through cell-autonomous mechanisms.

The G2019S substitution in the kinase domain of LRRK2 (LRRK2 G2019S ) is the most prevalent mutation associated with Parkinson's disease (PD). Neurotoxic effects of LRRK2 G2019S are thought to result from an increase in its kinase activity as compared to wild type LRRK2. However, it is unclear whether the kinase domain of LRRK2 G2019S is sufficient to trigger degeneration or if the full length protein is required. To address this question, we generated constructs corresponding to the C-terminal domain of LRRK2 (ΔLRRK2). A kinase activity that was increased by G2019➔S substitution could be detected in ΔLRRK2. However biochemical experiments suggested it did not bind or phosphorylate the substrate RAB10, in contrast to full length LRRK2. The overexpression of ΔLRRK2 G2019S in the rat striatum using lentiviral vectors (LVs) offered a straightforward and simple way to investigate its effects in neurons in vivo. Results from a RT-qPCR array analysis indicated that ΔLRRK2 G2019S led to significant mRNA expression changes consistent with a kinase-dependent mechanism. We next asked whether ΔLRRK2 could be sufficient to trigger neurodegeneration in the substantia nigra pars compacta (SNc) in adult rats. Six months after infection of the substantia nigra pars compacta (SNc) with LV-ΔLRRK2 WT or LV-ΔLRRK2 G2019S , the number of DA neurons was unchanged. To examine whether higher levels of ΔLRRK2 G2019S could trigger degeneration we cloned ΔLRRK2 in AAV2/9 construct. As expected, AAV2/9 injected in the SNc led to neuronal expression of ΔLRRK2 WT and ΔLRRK2 G2019S at much higher levels than those obtained with LVs. Six months after injection, unbiased stereology showed that AAV-ΔLRRK2 G2019S produced a significant ~30% loss of neurons positive for tyrosine hydroxylase- and for the vesicular dopamine transporter whereas AAV-ΔLRRK2 WT did not. These findings show that overexpression of the C-terminal part of LRRK2 containing the mutant kinase domain is sufficient to trigger degeneration of DA neurons, through cell-autonomous mechanisms, possibly independent of RAB10., (Copyright © 2019. Published by Elsevier Inc.)

The neurobiological functions of a number of kinases expressed in the brain are unknown. Here, we report new findings on DCLK3 (doublecortin like kinase 3), which is preferentially expressed in neurons in the striatum and dentate gyrus. Its function has never been investigated. DCLK3 expression is markedly reduced in Huntington's disease. Recent data obtained in studies related to cancer suggest DCLK3 could have an anti-apoptotic effect. Thus, we hypothesized that early loss of DCLK3 in Huntington's disease may render striatal neurons more susceptible to mutant huntingtin (mHtt). We discovered that DCLK3 silencing in the striatum of mice exacerbated the toxicity of an N-terminal fragment of mHtt. Conversely, overexpression of DCLK3 reduced neurodegeneration produced by mHtt. DCLK3 also produced beneficial effects on motor symptoms in a knock-in mouse model of Huntington's disease. Using different mutants of DCLK3, we found that the kinase activity of the protein plays a key role in neuroprotection. To investigate the potential mechanisms underlying DCLK3 effects, we studied the transcriptional changes produced by the kinase domain in human striatal neurons in culture. Results show that DCLK3 regulates in a kinase-dependent manner the expression of many genes involved in transcription regulation and nucleosome/chromatin remodelling. Consistent with this, histological evaluation showed DCLK3 is present in the nucleus of striatal neurons and, protein-protein interaction experiments suggested that the kinase domain interacts with zinc finger proteins, including the transcriptional activator adaptor TADA3, a core component of the Spt-ada-Gcn5 acetyltransferase (SAGA) complex which links histone acetylation to the transcription machinery. Our novel findings suggest that the presence of DCLK3 in striatal neurons may play a key role in transcription regulation and chromatin remodelling in these brain cells, and show that reduced expression of the kinase in Huntington's disease could render the striatum highly vulnerable to neurodegeneration.

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder resulting from a polyglutamine expansion in the huntingtin (HTT) protein. There is currently no cure for this disease, but recent studies suggest that RNAi to downregulate the expression of both normal and mutant HTT is a promising therapeutic approach. We previously developed a small hairpin RNA (shRNA), vectorized in an HIV-1-derived lentiviral vector (LV), that reduced pathology in an HD rodent model. Here, we modified this vector for preclinical development by using a tat-independent third-generation LV (pCCL) backbone and removing the original reporter genes. We demonstrate that this novel vector efficiently downregulated HTT expression in vitro in striatal neurons derived from induced pluripotent stem cells (iPSCs) of HD patients. It reduced two major pathological HD hallmarks while triggering a minimal inflammatory response, up to 6 weeks after injection, when administered by stereotaxic surgery in the striatum of an in vivo rodent HD model. Further assessment of this shRNA vector in vitro showed proper processing by the endogenous silencing machinery, and we analyzed gene expression changes to identify potential off-targets. These preclinical data suggest that this new shRNA vector fulfills primary biosafety and efficiency requirements for further development in the clinic as a cure for HD.

Recently, we described a modified AAV2 vector-AAV2-7m8-having a capsid-displayed peptide insertion of 10 amino acids with enhanced retinal transduction properties. The insertion of the peptide referred to as 7m8 is responsible for high-level gene delivery into deep layers of the retina when virus is delivered into the eye's vitreous. Here, we further characterize AAV2-7m8 mediated gene delivery to neural tissue and investigate the mechanisms by which the inserted peptide provides better transduction away from the injection site. First, in order to understand if the peptide exerts its effect on its own or in conjunction with the neighboring amino acids, we inserted the 7m8 peptide at equivalent positions on three other AAV capsids, AAV5, AAV8, and AAV9, and evaluated its effect on their infectivity. Intravitreal delivery of these peptide insertion vectors revealed that only AAV9 benefited from 7m8 insertion in the context of the retina. We then investigated AAV2-7m8 and AAV9-7m8 properties in the brain, to better evaluate the spread and efficacy of viral transduction in view of the peptide insertion. While 7m8 insertion led to higher intensity gene expression, the spread of gene expression remained unchanged compared to the parental serotypes. Our results indicate that the 7m8 peptide insertion acts by increasing efficacy of cellular entry, with little effect on the spread of viral particles in neural tissue. The effects of peptide insertion are capsid and tissue dependent, highlighting the importance of the microenvironment in gene delivery using AAV. Biotechnol. Bioeng. 2016;113: 2712-2724. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Astrocyte reactivity is a hallmark of neurodegenerative diseases (ND), but its effects on disease outcomes remain highly debated. Elucidation of the signaling cascades inducing reactivity in astrocytes during ND would help characterize the function of these cells and identify novel molecular targets to modulate disease progression. The Janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3) pathway is associated with reactive astrocytes in models of acute injury, but it is unknown whether this pathway is directly responsible for astrocyte reactivity in progressive pathological conditions such as ND. In this study, we examined whether the JAK/STAT3 pathway promotes astrocyte reactivity in several animal models of ND. The JAK/STAT3 pathway was activated in reactive astrocytes in two transgenic mouse models of Alzheimer's disease and in a mouse and a nonhuman primate lentiviral vector-based model of Huntington's disease (HD). To determine whether this cascade was instrumental for astrocyte reactivity, we used a lentiviral vector that specifically targets astrocytes in vivo to overexpress the endogenous inhibitor of the JAK/STAT3 pathway [suppressor of cytokine signaling 3 (SOCS3)]. SOCS3 significantly inhibited this pathway in astrocytes, prevented astrocyte reactivity, and decreased microglial activation in models of both diseases. Inhibition of the JAK/STAT3 pathway within reactive astrocytes also increased the number of huntingtin aggregates, a neuropathological hallmark of HD, but did not influence neuronal death. Our data demonstrate that the JAK/STAT3 pathway is a common mediator of astrocyte reactivity that is highly conserved between disease states, species, and brain regions. This universal signaling cascade represents a potent target to study the role of reactive astrocytes in ND., (Copyright © 2015 the authors 0270-6474/15/352817-13$15.00/0.)

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder resulting from polyglutamine expansion in the huntingtin (HTT) protein and for which there is no cure. Although suppression of both wild type and mutant HTT expression by RNA interference is a promising therapeutic strategy, a selective silencing of mutant HTT represents the safest approach preserving WT HTT expression and functions. We developed small hairpin RNAs (shRNAs) targeting single nucleotide polymorphisms (SNP) present in the HTT gene to selectively target the disease HTT isoform. Most of these shRNAs silenced, efficiently and selectively, mutant HTT in vitro. Lentiviral-mediated infection with the shRNAs led to selective degradation of mutant HTT mRNA and prevented the apparition of neuropathology in HD rat's striatum expressing mutant HTT containing the various SNPs. In transgenic BACHD mice, the mutant HTT allele was also silenced by this approach, further demonstrating the potential for allele-specific silencing. Finally, the allele-specific silencing of mutant HTT in human embryonic stem cells was accompanied by functional recovery of the vesicular transport of BDNF along microtubules. These findings provide evidence of the therapeutic potential of allele-specific RNA interference for HD.

Tissue-targeted expression is of major interest for studying the contribution of cellular subpopulations to neurodegenerative diseases. However, in vivo methods to investigate this issue are limited. Here, we report an analysis of the cell specificity of expression of fluorescent reporter genes driven by six neuronal promoters, with the ubiquitous phosphoglycerate kinase 1 (PGK) promoter used as a reference. Quantitative analysis of AcGFPnuc expression in the striatum and hippocampus of rodents showed that all lentiviral vectors (LV) exhibited a neuronal tropism; however, there was substantial diversity of transcriptional activity and cell-type specificity of expression. The promoters with the highest activity were those of the 67 kDa glutamic acid decarboxylase (GAD67), homeobox Dlx5/6, glutamate receptor 1 (GluR1), and preprotachykinin 1 (Tac1) genes. Neuron-specific enolase (NSE) and dopaminergic receptor 1 (Drd1a) promoters showed weak activity, but the integration of an amplification system into the LV overcame this limitation. In the striatum, the expression profiles of Tac1 and Drd1a were not limited to the striatonigral pathway, whereas in the hippocampus, Drd1a and Dlx5/6 showed the expected restricted pattern of expression. Regulation of the Dlx5/6 promoter was observed in a disease condition, whereas Tac1 activity was unaffected. These vectors provide safe tools that are more selective than others available, for the administration of therapeutic molecules in the central nervous system (CNS). Nevertheless, additional characterization of regulatory elements in neuronal promoters is still required.

Huntington's disease (HD) is a neurodegenerative disorder due to abnormal polyglutamine expansion in huntingtin protein (Exp-Htt). This expansion causes protein aggregation, leading to neuronal dysfunction and death. We have previously shown that mitogen- and stress-activated kinase (MSK-1), a nuclear protein kinase involved in chromatin remodeling through histone H3 phosphorylation, is deficient in the striatum of HD patients and model mice. Restoring MSK-1 expression in cultured striatal cells prevented neuronal dysfunction and death induced by Exp-Htt. Here we extend these observations in a rat model of HD based on striatal lentiviral expression of Exp-Htt (LV-Exp-HTT). MSK-1 overexpression attenuated Exp-Htt-induced down-regulation of DARPP-32 expression 4 and 10 weeks after infection and enhanced NeuN staining after 10 weeks. LV-MSK-1 induced constitutive hyperphosphorylation of H3 and cAMP-responsive element binding protein (CREB), indicating that MSK-1 has spontaneous catalytic activity. MSK-1 overexpression also upregulated peroxisome proliferator-activated receptor γ coactivator alpha (PGC-1α), a transcriptional co-activator involved in mitochondrial biogenesis. Chromatin immunoprecipitation indicated that transcriptional regulation of PGC-1α is directly linked to increased binding of MSK-1, along with H3 and CREB phosphorylation of the PGC-1α promoter. MSK-1 knock-out mice showed spontaneous striatal atrophy as they aged, as well as higher susceptibility to systemic administration of the mitochondrial neurotoxin 3-NP. These results indicate that MSK-1 activation is an important and key event in the signaling cascade that regulates PGC-1α expression. Strategies aimed at restoring MSK-1 expression in the striatum might offer a new therapeutic approach to HD.

Machado-Joseph disease or spinocerebellar ataxia type 3 (MJD/SCA3) is a fatal, autosomal dominant disorder caused by a cytosine-adenine-guanine expansion in the coding region of the MJD1 gene. RNA interference has potential as a therapeutic approach but raises the issue of the role of wild-type ataxin-3 (WT ATX3) in MJD and of whether the expression of the wild-type protein must be maintained. To address this issue, we both overexpressed and silenced WT ATX3 in a rat model of MJD. We showed that (i) overexpression of WT ATX3 did not protect against MJD pathology, (ii) knockdown of WT ATX3 did not aggravate MJD pathology and that (iii) non-allele-specific silencing of ataxin-3 strongly reduced neuropathology in a rat model of MJD. Our findings indicate that therapeutic strategies involving non-allele-specific silencing to treat MJD patients may be safe and effective.

Astrocytes are involved in key physiological brain processes, such as glutamatergic transmission and energy metabolism, often altered in neurodegenerative diseases. Targeted gene expression in astrocytes is needed to assess the contribution of these cells to physiological processes and for the development of new therapeutic strategies. However, most of the viral vectors currently used for gene transfer in the central nervous system (CNS) are highly neurotropic. We used mokola pseudotyping to shift the tropism of lentiviral vectors toward astrocytes and a detargeting strategy with miRNA to eliminate residual expression in neuronal cells. In primary cultures, we showed that incorporating target sequences for the neuron-specific miR124 effectively abolished transgene expression in neurons post-transcriptionally. Targeted expression of the LacZ reporter gene in astrocytes was achieved in the hippocampus, striatum, and cerebellum of the adult mouse in vivo. As a proof-of-principle, this new lentiviral vector was used to either overexpress or downregulate (RNA interference) the glial glutamate transporter GLAST into striatal astrocytes in vivo. These vectors provide new opportunities for cell type-specific gene transfer in the CNS., ((c) 2008 Wiley-Liss, Inc.)

Objective: Huntington's disease (HD) is a fatal autosomal dominant neurodegenerative disorder caused by a polyglutamine expansion in the huntingtin (htt) protein. No cure is available to date to alleviate neurodegeneration. Recent studies have demonstrated that RNA interference represents a promising approach for the treatment of autosomal dominant disorders. But whether an allele-specific silencing of mutant htt or a nonallele-specific silencing should be considered has not been addressed., Methods: We developed small hairpin RNA targeting mutant or wild-type htt transcripts, or both., Results: We confirmed the therapeutic potential of sihtt administered with lentiviral vectors in rodent models of HD and showed that initiation of small interfering RNA treatment after the onset of HD symptoms is still efficacious and reduces the HD-like pathology. We then addressed the question of the impact of nonallele-specific silencing and demonstrated that silencing of endogenous htt to 25 to 35% in vivo is altering several pathways associated with known htt functions but is not inducing overt toxicity or increasing striatal vulnerability up to 9 months after treatment., Interpretation: These data indicate that the coincident silencing of the wild-type and mutant htt may be considered as a therapeutic tool for HD.

Recent studies have demonstrated that RNAi is a promising approach for treating autosomal dominant disorders. However, discrimination between wild-type and mutant transcripts is essential, to preserve wild-type expression and function. A single nucleotide polymorphism (SNP) is present in more than 70% of patients with Machado-Joseph disease (MJD). We investigated whether this SNP could be used to inactivate mutant ataxin-3 selectively. Lentiviral-mediated silencing of mutant human ataxin-3 was demonstrated in vitro and in a rat model of MJD in vivo. The allele-specific silencing of ataxin-3 significantly decreased the severity of the neuropathological abnormalities associated with MJD. These data demonstrate that RNAi has potential for use in MJD treatment and constitute the first proof-of-principle for allele-specific silencing in the central nervous system.

Background: Prolonged, altered hematopoietic reconstitution is commonly observed in patients undergoing myeloablative conditioning and bone marrow and/or mobilized peripheral blood-derived stem cell transplantation. We studied the reconstitution of myeloid and lymphoid compartments after the transplantation of autologous CD34+ bone marrow cells following gamma irradiation in cynomolgus macaques., Results: The bone marrow cells were first transduced ex vivo with a lentiviral vector encoding eGFP, with a mean efficiency of 72% +/- 4%. The vector used was derived from the simian immunodeficiency lentivirus SIVmac251, VSV-g pseudotyped and encoded eGFP under the control of the phosphoglycerate kinase promoter. After myeloid differentiation, GFP was detected in colony-forming cells (37% +/- 10%). A previous study showed that transduction rates did not differ significantly between colony-forming cells and immature cells capable of initiating long-term cultures, indicating that progenitor cells and highly immature hematopoietic cells were transduced with similar efficiency. Blood cells producingeGFP were detected as early as three days after transplantation, and eGFP-producing granulocyte and mononuclear cells persisted for more than one year in the periphery., Conclusion: The transplantation of CD34+ bone marrow cells had beneficial effects for the ex vivo proliferation and differentiation of hematopoietic progenitors, favoring reconstitution of the T- and B-lymphocyte, thrombocyte and red blood cell compartments.

Infection of primates by HIV-1 and SIV induces multiple hematological abnormalities of central hematopoietic origin. Although these defects greatly contribute to the pathophysiology of HIV-1 infection, the molecular basis for altered BM function remains unknown. Here we show that when cynomolgus macaques were infected with SIV, the multipotent potential of their hematopoietic progenitor cells was lost, and this correlated with downregulation of STAT5A and STAT5B expression. However, forced expression of STAT5B entirely rescued the multipotent potential of the hematopoietic progenitor cells. In addition, an accessory viral protein required for efficient SIV and HIV replication and pathogenicity, "Negative factor" (Nef), was essential for SIV-mediated impairment of the multipotent potential of hematopoietic progenitors ex vivo and in vivo. This newly uncovered property of Nef was both conserved between HIV-1 and SIV strains and entirely dependent upon the presence of PPARgamma in targeted cells. Further, PPARgamma agonists mimicked Nef activity by inhibiting STAT5A and STAT5B expression and hampering the functionality of hematopoietic progenitors both ex vivo and in vivo. These findings have extended the role of Nef in the pathogenicity of HIV-1 and SIV and reveal a pivotal role for the PPARgamma/STAT5 pathway in the regulation of early hematopoiesis. This study may provide a basis for investigating the potential therapeutic benefits of PPARgamma antagonists in both patients with AIDS and individuals with hematopoietic disorders.

We report a fortuitous discovery of primary pulmonary myxoid liposarcoma in an HIV-positive patient. Primary pulmonary localizations are uncommon. Generally, pulmonary localizations are metastatic. There is a male predominance and diagnosis is generally made around 40 years of age. The two main features of liposarcoma are the large tumor size and the complex histology that evolves over time. Pathology findings are rarely reproducible and vary from one pathologist to another. Macroscopically, liposarcomas can mimic benign tumors. The risk of recurrence is high after simple enucleation due to microscopic extracapsular extensions. Surgery remains the predominant treatment. Wide complete excision, if possible, provides long-term survival.

Objective: The purpose of this study was to determine the clinical, radiographic, and ultrasonographic aspects of mediastinal nodal tuberculosis and ascertain its clinical course in the era of HIV infection., Patients and Methods: We reviewed retrospectively 39 patients referred to the Ouédraogo Yalgado National Hospital Center and the National Anticancer Institute between February 1996 and December 1999 for mediastinal nodal tuberculosis. Endoscopic proof of tuberculosis was obtained in 30 cases (81.8%). HIV serology was positive in 26 of the 30 patients tested (86.6%)., Results: Nodal mediastinal tuberculosis accounted for 1.7% of the cases of tuberculosis recorded over the same period at the Anticancer Institute. Mean age of the patients was 32.8 years and the sex ratio was 1.05 in favor of men. Clinically, a past medical history was found in 18 cases (46%) including a herpes zoster in 6 (15.4%), cough in 38 (97.5%). Weight loss (95%), fever (100%) and peripheral node enlargement (20%) were found frequently, probably related to HIV infection more than tuberculosis. Radiographically, standard x-rays evidenced associated lesions in 22 cases, with 59% having predominant parenchymatous lesions. Other localizations of tuberculosis were very frequent (42.5%)., Discussion: Bronchial fibroscopy is most contributive to diagnosis of mediastinal nodal tuberculosis with an 81.8% yield in our series. HIV infection had a determining effect on the disease course since among the 16 patients who died, 14 were HIV-positive (52%).

Setting: The cost and availability of the medications required for the treatment of asthma may represent potential barriers to effective management., Method: A survey of prices and policies for components of asthma treatment in 1998, in Algeria, Burkina Faso, Ivory Coast, Guinea, Mali, Syria, Turkey and Vietnam., Results: Medications were consistently available in only four of the eight countries studied. The cost of essential medications for standard case management varied by over five times for beclomethasone and by over three times for inhaled salbutamol. In all but two countries, the cost of one year of drugs for treatment of a moderate, persistent case exceeded the monthly salary of a nurse in that country. The essential drugs list included inhaled salbutamol in five of eight countries and beclomethasone in three of eight. The costs of medications were lower where generic preparations were available and, to a lesser extent, where the medications are on the essential drugs list., Conclusions: The cost and availability of medications vary widely, and may represent an important barrier to effective management in some low and middle income countries.

Background: Neonatal and/or congenital tuberculosis is insufficiently understood., Case Reports: Case 1. A premature hypotrophic neonate presented at the age of 45 days, without any maternal contact, a bilateral bronchopneumopathy. Whilst the pregnancy and birth had not been affected by any noteworthy problem, the mother died from miliary tuberculosis despite rifampin, isoniazid and pyrazinamide treatment. Her baby also died on day 52 from multivisceral failure. Culture of tracheal secretions confirmed a few weeks later the diagnosis of tuberculosis. Case 2. A premature, hypotrophic neonate presented on day 22 signs of respiratory distress (miliary), icterus and hepatosplenomegaly. Whilst the pregnancy and birth had not been affected by any particular problem, the mother, 18 days after giving birth, presented miliary and pleural tuberculosis. Despite treatment with rifampin, isoniazid and pyrazinamid started on day 22, the baby died on day 27 from multivisceral failure. The post-mortem liver biopsy confirmed the diagnosis of tuberculosis. Case 3. A baby born at term was hospitalized on day 4 for jaundice. Whilst the pregnancy and birth had not presented any problem, the mother developed a pleural tuberculosis on day 10. Breast-feeding was stopped. Due to the presence of opacities at the top of the right lung, the child was given rifampin, isioniazid, and pyrazinamide. The course was marked by the appearance of hepatomegaly and poor weight gain up to day 25, followed by an improvement., Conclusion: The frequency of congenital tuberculosis is probably under-estimated. Its early diagnosis is essential but often difficult as the initial manifestations are delayed. Improved screening of women at risk and sensitization of the medical community are necessary.

One hundred years after Yersin discovered Yersinia pestis during the plague epidemic in Hong Kong in 1894, human plague still has not been eliminated. The epidemic in 1994 in India, a country where no cases had been observed since 1996, raised great concern. Plague is an epizootic bacterial infection caused by a Gram negative coccobacillus, Y. pestis, transmitted by the bite of infected fleas. Bubonic plague is the most common form. Other clinical presentations include asymptomatic plague, abortive plague, pharyngeal plague, septicemic plague, meningeal plague, and primary or secondary pneumonic plague which is observed in 5 to 20% of cases. Plague is a highly communicable disease between humans despite antibiotic therapy which has reduced mortality by 80%. The prognosis depends on early diagnosis. Streptomycin and cyclines are the gold standard treatment.

Objective: To develop a scoring system for screening children for tuberculosis (TB) and for selecting suspects for further investigation in tuberculosis control programmes. Application of the score model, which would not require sophisticated or expensive technology, would be directed towards resource-poor countries with high prevalences of tuberculosis, where health care workers have to deal with diagnostic problems away from district hospitals or diagnostic facilities., Design: Based on contributions from members of an IUATLD task group from 10 countries on the use of diagnostic criteria in childhood tuberculosis, criteria were selected to be used as elements in a score model. Data were collected by standardised questionnaire on 879 subjects aged under 15 years. Of these, 794 were considered probable or confirmed cases of tuberculosis by the diagnosing doctors. From each record, the criteria/procedures used in the diagnosis of probable/confirmed TB and regarded by the doctors as relevant criteria were selected. Bacteriology, histology and chest radiography were used either singly or collectively as the definitive reference (gold standard) against which the more subjective criteria (symptoms, clinical signs, skin test) would be evaluated. The latter criteria cited as relevant were then ranked and further explored for inclusion in the score model. The relative importance of each criterion to every other criterion on the list was expressed as weights, determined by employing a logarithmic least squares method to solve the ratio scale estimation problem which underlies decision-making involving more than one criterion. The resultant values were then assigned to each criterion in the final score model., Results: The five clinical criteria thought to be most relevant as predictors of disease in children were history of contact with a case of tuberculosis, positive skin test, persistent cough, low weight for age, and unexplained/prolonged fever. In selecting the optimal cut-off points for the model at which tuberculosis would be suspected, low sensitivity and specificity (below 70%) but reasonably good positive predictive values (60%-77%) were obtained, depending on age group and epidemiological setting. In low tuberculosis prevalence settings, heavy reliance is placed by the model on a history of contact with a household case of tuberculosis and on a positive skin test, both of which have to be true. For high prevalence settings, more or less equal weighting is assigned to all five elements. Case contact and skin tests are less important, with low body weight, prolonged fever and cough being more indicative of tuberculosis., Conclusion: The model provides for epidemiological differences between target populations and should prove successful as a screening tool to select children for further investigation by radiography and bacteriology.

The indicators used in the struggle against tuberculosis, particularly in developing countries, can be separated into two groups. First, the variables, are indicators of the overall damage caused by the disease in the community. Secondly, the parameters, are the calculated indicators of the risk for tuberculosis faced by the individual. Their presentation here follows the pragmatic concerns of the coordinators of the programs: evaluating the scale of the tuberculosis problem; ensuring its surveillance and the supervision of a prevention program; and diffusing the information required to stir the program workers and the population into action to fight tuberculosis. Among the variables, the incidence of mortality lost significance. The emphasis is now on the incidence of the new cases of contagious pulmonary tuberculosis as well as the calculation of the Annual Risk of Infection (ARI). The ARI, despite serious criticisms, remains one of the best indicators for the study of tuberculosis. The data obtained from an active program must be standardized to allow comparisons of the declared cases as well as their follow-up after the initiation of the treatment. The parameters enable a mathematical representation of the different stages in the natural development of the disease: the risk to be infected; the risk of becoming ill; and the development of the illness. These parameters can be advantageously used to mobilize the people into action. The pandemic of HIV drastically changed the natural history of tuberculosis. HIV infection is the most important factor of the transition from tuberculosis infection to active tuberculosis. The HIV pandemic also modified the epidemiological estimations of tuberculosis. In particular, it reinforced the criticisms made against the ARI. The surveillance of the prevalence of HIV among tuberculosis patients is thus important data.

In 1980, a 32 years-old Madagascan female developed a pulmonary tuberculosis, bacteriologically confirmed. She cured with right apical cavitary sequellae. In 1989, she presented haemoptysis again. Antituberculous treatment was adopted without bacteriological confirmation and did not improve clinical symptoms. In 1991 and 1992 cultures from sputa and bronchi aspiration yielded acid-fast bacilli identified as Mycobacterium shimoïdei. M. tuberculosis could not be detected. The patient died during treatment. This case is the fourth one in the literature. Whereas previous cases have been reported in Europe, Australia, Asia, this new case shows M. shimoïdei is also present in Africa.

The genetic polymorphism of the mycobacteria of the tuberculosis complex in the city of Antananarivo was studied on 126 strains isolated from positive microscopy pulmonary tuberculosis patients. The genetic profiles established using the RFLP technic and the IS6110 marker yielded 83 clusters of 1 to 29 strains. There were 34 strains with a IS6110 unique band profile of which 29 had a band located at 1.4-1.5 kb. These strains could be differentiated using a second marker, the DR marker. 3 strains with an unique IS6110 band located at 1.8-1.9 kb were identified as M. bovis. In general, there was no evident epidemiological relationship between the patients presenting with identical profiles. In the prison of Antananarivo, the IS6110 typing of 36 strains yielded 28 clusters of 1 to 3 strains. Excepting 2 clusters showing an internal contamination, the absence of profiles specific to the jail suggests that the patients were probably contaminated before their entrance. This preliminary study shows that the RFLP profiles of M. tuberculosis, using the IS6110 and the DR markers, were polymorphic enough for using this method to study the transmission in Antananarivo.

A 56 months retrospective study, from October 1990 to May 1995, at the Centre Hospitalier de Soavinandriana in Antananarivo pointed out 29 tuberculous pericarditis among the 97 pericardial effusions discovered by the echocardiography of 5600 patients. The sex-ratio was 0,81 and the mean age 38,6 years old (+/- 14,3). Hospitalization was justified by dyspnea (18 cases), thoracic pain (18 cases), lower limbs edema (6 cases) and ascitis (3 cases). Moreover, electrocardiography showed microvoltage in 18 cases and thoracic radiography showed one heart enlargement. Even if for 15 cases a pleural effusion was associated, only 2 patients had a pulmonary image suggestive of tuberculosis. Tuberculous pericarditis has been proved by the following examinations: pericardium puncture (21 cases), pericardium and pleural biopsy (respectively 11 and 13 cases), ganglionic biopsy and search of alcohol-acid-fast bacilli in sputum: 1 case. Histologic proof has been obtained 8 times out of 9 pericardial biopsies and 6 times out of 7 pleural biopsies. Bacteriological proof has been obtained 11 times by pathological samples cultivation: twice from fresh caseous material taken from the pericardium, once from 13 pleural fluids, 5 times from 6 pericardial biopsies, 3 times from 3 pleural biopsies. The patients have been put under antituberculous treatment associated with prednisone. 20 patients have been declared cured at the end of the treatment, 5 were dead and 4 were lost out of sight. Tuberculous pericarditis has become rare in developed countries but it is still challenging in Madagascar. In spite of the antituberculous treatment associated with corticoids, prognosis is severe (evolution towards pericardial constriction death.

A survey was undertaken in April 1993 to compare the respective benefits of 2 regimens containing either streptomycin (SHRZ) or ethambutol (EHRZ) in the first two months of treatment of smear-positive pulmonary tuberculosis in Madagascar. This operational research was justified by the risks related to the use of parenteral streptomycin in a country where single use material is rare and its purpose was to provide arguments for an eventual recommendation to replace this drug by oral ethambutol which is also less expensive. 907 patients were included. The compliance was not significantly different between the 2 groups, although it was traditionally assumed to be better with streptomycin. The frequency of side effects was significantly lower with EHRZ. Overall treatment failure rates were not significantly different, but all of 6 patients who were negative at 5 months and were again positive at 8 months had received EHRZ. This point obliged to be careful before concluding, because 24% of patients were lost for follow-up. A 2 years surveillance will be necessary to compare the frequency of recurrences.

The experience of a 51 months continuous action of tuberculosis control in a pneumophysiology department of an important general hospital which works according to the principle of cost recovery, is reported. This centre, with an average of 345 annual cases, is the third in Madagascar. During the studied period (from September 1989 to December 1993), 1418 tubercular patients have been diagnosed, distributed into 57.7% of pulmonary tuberculosis and 42.3% of extrapulmonary tuberculosis. The number of extrapulmonary tuberculosis is obviously higher than in the rest of the country structure (16%); among them, pleurisies are distinctly prevailing (present in 29.6% of tubercular patients), other serositis take an important place, immediately after peripheric adenopathies (101 cases that is to say 7.1%); the high proportion of laryngitis shows the importance and oldness of bacilli infected pulmonary lesions. 13.7% of the patients have two or more tubercular localizations. Bacteriological proof has been done for 97.3% of the pulmonary tuberculosis and 7% of the extrapulmonary tuberculosis. A certitude proof has globally been acquired for 82.5% of the patients. 97.9% of the sick started a treatment. 7% of death were noted (95 cases), two thirds of them during the first month after diagnosis and two thirds due to pulmonary tuberculosis with positive microscopy. The average recovery rate within the studied period was 68.2% for all patients without distinction; 67.6% (456/674) for pulmonary tuberculosis with positive microscopy and 76% (265/349) for pulmonary tuberculosis with positive microscopy among civil servants and equivalent. It has been noted that private persons who pay their medical expenses showed a significantly less good compliance (60.9% of recovery rate) than civil servants whose medical expenses are entirely refunded.

A group of 122 observations of pediatric tuberculosis has been studied. Nurslings represented 34% of the group, children under 8 years old 75% and only 10% were above 12. The sex ratio was 1,1. In a statistically significant way, tuberculous children were less often immunized by BCG than reference children not infected by tuberculosis. Contact has been traced back to close family in 42% of cases. Weight loss was significant at diagnosis time and after treatment the difference with the reference group disappeared. Extrapulmonary localizations were less frequent with children under 2, pulmonary and extrapulmonary localizations associations could be observed with 14% of children under 2 and with 31% of the whole children developing a proved tuberculosis. The importance of bronchial fibroscopy has been pointed out, for it allowed to detect 30% of abnormalities and to prove the diagnosis of tuberculous in 25% of cases. It is regrettable that the National Tuberculosis Control Programme did not prescribe chemoprophylaxis of contact children in its routine instructions, yet it is well known that child tuberculosis is rarely contagious and is not considered a priority by a programme. Finally, the authors reported that the number of pediatric tuberculosis managed in the country showed an obvious underestimation of the problem and they hope this work would lead to think more frequently of that diagnosis in the future.