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1.  Effect of the enzyme and PCR conditions on the quality of high-throughput DNA sequencing results 
Scientific Reports  2015;5:8056.
Library preparation protocols for high-throughput DNA sequencing (HTS) include amplification steps in which errors can build up. In order to have confidence in the sequencing data, it is important to understand the effects of different Taq polymerases and PCR amplification protocols on the DNA molecules sequenced. We compared thirteen enzymes in three different marker systems: simple, single copy nuclear gene and complex multi-gene family. We also tested a modified PCR protocol, which has been suggested to reduce errors associated with amplification steps. We find that enzyme choice has a large impact on the proportion of correct sequences recovered. The most complex marker systems yielded fewer correct reads, and the proportion of correct reads was greatly affected by the enzyme used. Modified cycling conditions did reduce the number of incorrect sequences obtained in some cases, but enzyme had a much greater impact on the number of correct reads. Thus, the coverage required for the safe identification of genotypes using one of the low quality enzymes could be seven times larger than with more efficient enzymes in a biallelic system with equal amplification of the two alleles. Consequently, enzyme selection for downstream HTS has important consequences, especially in complex genetic systems.
PMCID: PMC4306961  PMID: 25623996
2.  At the southeast fringe of the Bantu expansion: genetic diversity and phylogenetic relationships to other sub-Saharan tribes 
Meta Gene  2014;2:670-685.
Here, we present 12 loci paternal haplotypes (Y-STR profiles) against the backdrop of the Y-SNP marker system of Bantu males from the Maputo Province of Southeast Africa, a region believed to represent the southeastern fringe of the Bantu expansion. Our Maputo Bantu group was analyzed within the context of 27 geographically relevant reference populations in order to ascertain its genetic relationship to other Bantu and non Bantu (Pygmy, Khoisan and Nilotic) sub-equatorial tribes from West and East Africa. This study entails statistical pair wise comparisons and multidimensional scaling based on YSTR Rst distances, network analyses of Bantu (B2a-M150) and Pygmy (B2b-M112) lineages as well as an assessment of Y-SNP distribution patterns. Several notable findings include the following: 1) the Maputo Province Bantu exhibits a relatively close paternal affinity with both east and west Bantu tribes due to high proportion of Bantu Y chromosomal markers, 2) only traces of Khoisan (1.3%) and Pygmy (1.3%) markers persist in the Maputo Province Bantu gene pool, 3) the occurrence of R1a1a-M17/M198, a member of the Eurasian R1a-M420 branch in the population of the Maputo Province, may represent back migration events and/or recent admixture events, 4) the shared presence of E1b1b1-M35 in all Tanzanian tribes examined, including Bantu and non-Bantu groups, in conjunction with its nearly complete absence in the West African populations indicate that, in addition to a shared linguistic, cultural and genetic heritage, geography (e.g., east vs. west) may have impacted the paternal landscape of sub-Saharan Africa, 5) the admixture and assimilation processes of Bantu elements were both highly complex and region-specific.
Graphical abstract
Exhibiting partitioning of Maputo individuals away from West and East African Bantu populations.
Network projection of the B2a-M150 Bantu marker
•Maputo Bantus exhibit close affinities with other West and East African Bantus.•Traces of Khoisan and Pygmy markers persist in the Maputo Province Bantus.•R1a1a-M17/M198 in the Maputo Province may represent back or recent migration.•Linguistic, cultural and genetic heritages are reflected in Maputo's gene pool.•Admixture and assimilation processes of Bantu elements were region-specific.
PMCID: PMC4287857  PMID: 25606451
SNP, single nucleotide polymorphism; STR, short tandem repeat; mtDNA, mitochondrial DNA; MAP, Maputo Province; PCR, polymerase chain reaction; RFLP, restriction fragment length polymorphism; MJ, medial joining; MDS, multi-dimensional scaling; TMRCA, time of most recent common ancestor; Bantu; Africa; Phylogenetics; Y-chromosome; Y-STRs; Population genetics
3.  Study of Hydatidosis-Attributed Mortality in Endemic Area 
PLoS ONE  2014;9(3):e91342.
Cystic hydatid disease is still an important health problem in European Mediterranean areas. In spite of being traditionally considered as a “benign” pathology, cystic echinococcosis is an important cause of morbidity in these areas. Nevertheless, there are few analyses of mortality attributed to human hydatidosis.
To describe the epidemiology, the mortality rate and the causes of mortality due to E. granulosus infection in an endemic area.
A retrospective study followed up over a period of 14 years (1998–2011).
Principal Findings
Of the 567 patients diagnosed with hydatid disease over the period 1998–2011, eleven deaths directly related to hydatid disease complications were recorded. Ten patients (90.9%) died due to infectious complications and the remaining one (9.1%) died due to mechanical complications after a massive hemoptysis. We registered a case fatality rate of 1.94% and a mortality rate of 3.1 per 100.000 inhabitants.
Hydatidosis is still a frequent parasitic disease that causes a considerable mortality. The main causes of mortality in patients with hydatidosis are complications related to the rupture of CE cysts with supurative collangitis. Therefore, an expectant management can be dangerous and it must be only employed in well-selected patients.
PMCID: PMC3954695  PMID: 24632824
4.  Evidence for Mycobacteria in Sarcoidosis 
Despite its recognition as a distinct granulomatous disease for over a century, the etiology of sarcoidosis remains to be defined. Since the early 1900s, infectious agents have been suspected in causing sarcoidosis. For much of this time, mycobacteria were considered a likely culprit, yet until recently, the supporting evidence has been tenuous at best. In this review, we evaluate the reported association between mycobacteria and sarcoidosis. Historically, mycobacterial infection has been investigated using histologic stains, cultures of lesional tissue or blood, and identification of bacterial nucleic acids or bacterial antigens. More recently, advances in biochemical, molecular, and immunological methods have produced a more rigorous analysis of the antigenic drivers of sarcoidosis. The result of these efforts indicates that mycobacterial products likely play a role in at least a subset of sarcoidosis cases. This information, coupled with a better understanding of genetic susceptibility to this complex disease, has therapeutic implications.
PMCID: PMC3361363  PMID: 21659662
sarcoidosis; mycobacteria; granulomas; microorganisms; peptides; immune response
5.  Palladium(0)-Catalyzed Arylative Dearomatization of Phenols 
The palladium-catalyzed arylative dearomatization of phenols to yield spirocyclohexadienone products in good to excellent yields has been developed. Preliminary results demonstrate that the formation of the spirocyclic all-carbon quaternary center can be accomplished with high levels of enantiocontrol (up to 91% ee).
PMCID: PMC3124856  PMID: 21612204
6.  Cystic Echinococcosis in Spain: Current Situation and Relevance for Other Endemic Areas in Europe 
Cystic echinococcosis (CE) remains an important health problem in many regions of the world, both where no control measures have been implemented, and where control programs have been incompletely successful with ensuing re-emergence of the disease. In Spain, official data on CE show an increase in the proportion of intermediate hosts with CE during the last few years, and autochthonous pediatric patients have been reported, a sign of active local transmission of disease. A similar picture emerges from data reported to the European Food Safety Authority by other European countries. Nevertheless, several crucial aspects related to CE that would help better understand and control the disease have not been tackled appropriately, in particular the emergence of infection in specific geographical areas. In this respect, while some data are missing, other data are conflicting because they come from different databases. We review the current situation of CE in Spain compared with areas in which similar problems in the CE field exist, and offer recommendations on how to overcome those limitations. Specifically, we believe that the introduction of national registries for CE with online data entry, following the example set by the European Registry for Alveolar Echinococcosis, would help streamline data collection on CE by eliminating the need for evaluating and integrating data from multiple regions, by avoiding duplication of data from patients who access several different health facilities over time, and by providing much needed clinical and epidemiological data that are currently accessible only to clinicians.
PMCID: PMC3026768  PMID: 21283615
7.  Dendritic Cells in the Pathogenesis of Sarcoidosis 
Sarcoidosis is a noncaseating granulomatous disease, likely of autoimmune etiology, that causes inflammation and tissue damage in multiple organs, most commonly the lung, but also skin, and lymph nodes. Reduced dendritic cell (DC) function in sarcoidosis peripheral blood compared with peripheral blood from control subjects suggests that blunted end organ cellular immunity may contribute to sarcoidosis pathogenesis. Successful treatment of sarcoidosis with tumor necrosis factor (TNF) inhibitors, which modulate DC maturation and migration, has also been reported. Together, these observations suggest that DCs may be important mediators of sarcoidosis immunology. This review focuses on the phenotype and function of DCs in the lung, skin, blood, and lymph node of patients with sarcoidosis. We conclude that DCs in end organs are phenotypically and functionally immature (anergic), while DCs in the lymph node are mature and polarize pathogenic Th1 T cells. The success of TNF inhibitors is thus likely secondary to inhibition of DC-mediated Th1 polarization in the lymph node.
PMCID: PMC2809219  PMID: 19372243
sarcoidosis; granuloma; dendritic cell; macrophage; inflammation
8.  Lactobacillus casei strain GG in the treatment of infants with acute watery diarrhea: A randomized, double-blind, placebo controlled clinical trial [ISRCTN67363048] 
BMC Pediatrics  2004;4:18.
Adjuvant therapy to ORT with probiotic bacteria for infants with acute watery diarrhea has been under active investigation. Most studies have been done in the developed world showing benefit only for viral mild gastroenteritis. We evaluated the effect of a milk formula containing one billion (109) cfu/ml of Lactobacillus casei strain GG (LGG) upon duration and severity of diarrhea in infants in an environment with more severe acute diarrhea, where etiologic agents other than rotavirus are involved more frequently, and where mixed infections are more prevalent.
Male infants aged 3–36 months brought for treatment of acute watery diarrhea of less than 48 hours were eligible. After rehydration was completed with the WHO's oral rehydration solution, patients were randomly assigned to receive a milk formula either containing LGG or not. Stool volume was periodically measured using a devise suited to collect stools separate from urine. Duration of diarrhea was estimated based on stools physical characteristics.
Eighty nine patients received the placebo milk formula and ninety received the LGG containing formula. Both groups were comparable in their baseline characteristics. Total stool output was significantly larger (p = 0.047) in the LGG group (247.8 ml/kg) than in the placebo group (195.0 ml/kg). No significant differences were found in duration of diarrhea (58.5 hours with LGG vs. 50.4 hours with placebo), rate of treatment failure (21.1% with LGG vs. 18.0% with placebo), and proportion of patients with unresolved diarrhea after 120 hours (12.2% with LGG vs. 12.5% with placebo). The rate of stools with reducing substances after 24 hours of treatment increased significantly in both groups (from 41.4% to 72.2% with LGG and from 45.9% to 68.0% with placebo).
This study did not show a positive effect of LGG on the clinical course of acute watery diarrhea. Positive beneficial effects of LGG, as had been reported elsewhere, could have been masked in our study by worsening diarrhea due to transient lactose malabsorption. Further studies with low-lactose or non-lactose conveyors of LGG are desirable.
PMCID: PMC517719  PMID: 15345099

Results 1-8 (8)