Specific genetic markers for detecting subtypes of dengue virus serotype-2 in isolates from the states of Oaxaca and Veracruz,Mexico

Background  

Dengue (DEN) is an infectious disease caused by the DEN virus (DENV), which belongs to the Flavivirus genus in the family Flaviviridae. It has a (+) sense RNA genome and is mainly transmitted to humans by the vector mosquito Aedes aegypti. Dengue fever (DF) and dengue hemorrhagic fever (DHF) are caused by one of four closely related virus serotypes (DENV-1, DENV-2, DENV-3 and DENV-4). Epidemiological and evolutionary studies have indicated that host and viral factors are involved in determining disease outcome and have proved the importance of viral genotype in causing severe epidemics. Host immune status and mosquito vectorial capacity are also important influences on the severity of infection. Therefore, an understanding of the relationship between virus variants with altered amino acids and high pathogenicity will provide more information on the molecular epidemiology of DEN. Accordingly, knowledge of the DENV serotypes and genotypes circulating in the latest DEN outbreaks around the world, including Mexico, will contribute to understanding DEN infections.     

Five new species of pteridophytes from Oaxaca,Mexico

Five new species are described from the state of Oaxaca in southern Mexico:Huperzia beiteliana Mickel,Ophioglossum dudadae Mickel,Selaginella basipilosa Valdespino,Selaginella mickelii Valdespino, andSelaginella nothohybrida Valdespino.     

Phytoplankton from Tehuantepec River, Oaxaca, Mexico and some biogeographical relationships

Phytoplankton species collected from the limnetic to euryhaline sections of Tehuantepec River were identified, classified and compared with regional information from Mexico and South America. We collected 15 samples every three months from July 1997 through August 1998 with a 20 microm net and a Van Dorn bottle. Indicator values and a code checklist are included. A total of 58 families, 121 genera, 273 species, one subspecies, 75 varieties, 13 forms and one morphotype were identified in the taxa Bacillariophyta (42.0 %), Chlorophyta (29.0 %), Cyanoprocaryota (18.0 %), Euglenophyta (5.0 %), Dinophyta (3.0 %), Cryptophyta (2.0 %) and Chrysophyta (1.0 %). The predominant families were Scenedesmaceae (24 species), Oocystaceae (22), Bacillariophyceae (21), Chaetocerotaceae (15) and Euglenaceae (14). Five families, eight genera, 72 species, 45 varieties and eight forms are first records for Mexico. The species Chroococcus turgidus, Microcystis flosaquae and Pseudanabaena limnetica (which produce massive blooms or red tides) are important in this river of moderate water quality.     

Plants used for reproductive health in Oaxaca,Mexico

Despite the existence of 2 government health centers in Mexico's San Francisco township, the use of herbal remedies for the treatment of reproductive health problems and the management of reproduction is almost universal. An ethnographic study conducted in 1980-1981 of 180 women and 126 women investigated use of specific herbal remedies in this highland area. The largest number of reproduction-related medicinal plants used San Francisco are for postpartum recovery. In fact, 80% of the women interviewed reported using only herbal remedies after their last delivery. These remedies are relied on to restore lost blood, heal the birth scar, and stop bleeding. Of the 40% of respondents who reported postpartum hemorrhaging, 70% used herbal remedies. Several of the plants used to treat menorrhagia and hemorrhaging are also used for infertility. The infertility remedies are believed to cleanse the blood and uterus, heal or strengthen the back so the fetus can adhere, help the womb retain the fetus, and cool the blood. Both infertility and miscarriage are attributed to incomplete postpartum recovery. Another large group of medicinal remedies is employed to speed labor or ease labor pains. These remedies are thought to stimulate blood flow or uterine contractions. An additional 15 plants are used to prevent or terminate pregnancy. The mechanism of action in these case is believed to be to both warm the blood to facilitate its flow and irritate the uterus so it will evacuate its contents. Reliance on these remedies derives from Chinantec ethnomedical understandings. Given the persistence of use of herbal remedies in many communities in the Third World, research is needed on their safety and efficacy.     

Begonia lyman-smithii (Begoniaceae), a new species from Oaxaca,Mexico

Begonia (sect.Gireoudia)lyman-smithii is described and illustrated, and its relationships are discussed.     

A new species of Ornithocephalus (Orchidaceae) from Oaxaca,Mexico

Ornithocephalus torresii Salazar & Soto Arenas, a new species from the Pacific slope of Oaxaca. Mexico, is described and illustrated. It is distinguished by the nearly closed, globose flowers and the cymbiform lip with a small, irregularly dentate-lacerate lobule at each side of the base. A key to all the species ofOrnithocephalus hiterto recorded from Mexico is provided.     

Tillandsia tomasellii (Bromeliaceae), a new species from Oaxaca,Mexico

Tillandsia tomasellii from Río Hondo, Oaxaca, Mexico, is described and compared to related speciesT. xerographica andT. fasciculata.     

A new species in the genus Dioon (Zamiaceae) from north-central Oaxaca, Mexico

Dioon argenteum sp. nov. (Zamiaceae) is described from northern Oaxaca, México. Flat leaves, and persistently tomentose, slightly imbricate leaflets with marginal prickles characterize this species. The specific epithet argenteum was chosen to describe the silver appearance of the persistent tomentum covering the new leaves. D. argenteum appears to have affinities with D. purpusii and D. califanoi.   © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 471–476.     

Tigridia amatlanensis (Tigridieae: Iridaceae), a new species from Oaxaca, Mexico

Tigridia amatlanensis is described and illustrated as a new species from Mexico. It is recognized by its nodding flowers and its inner and outer tepals cirrhous and markedly dimorphic in length. It is most closely related toT. hallbergii subsp.hallbergii andT. meleagris. Other morphologically similar species areT. catarinensis andT. molseediana.     

A new species of Sicyos L. (Cucurbitaceae) from Oaxaca, Mexico

Sicyos mcvaughii, a new species from Oaxaca, is described and illustrated. It is similar to Sicyos sertuliferus Cogn., and grows in secondary tropical deciduous forest, between 20 and 630 meters.     

Two new species of Sicyos (Cucurbitaceae) from Guerrero and Oaxaca, Mexico

Two new species of Sicyos from Mexico are described and illustrated: Sicyos cordifolius from the state of Guerrero, which belongs to the group with dry, armed fruits, and Sicyos bulbosus from the state of Oaxaca, which belongs to the group with fleshy, unarmed fruits. Sicyos cordifolius is quite different from the rest of the species previously described. Although S. bulbosus is very similar to S. galeottii Cogn., it is clearly different in receptacle shape and size.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 373–378.     

Isolation and characterization of dengue virus serotype 2 from the large dengue outbreak in Guangdong,China in 2014

Dengue has been well recognized as a global public health threat,but only sporadic epidemics and imported cases were reported in recent decades in China.Since July 2014,an unexpected large dengue outbreak has occurred in Guangdong province,China,resulting in more than 40000 patients including six deaths.To clarify and characterize the causative agent of this outbreak,the acute phase serum from a patient diagnosed with severe dengue was subjected to virus isolation and high-throughput sequencing(HTS).Traditional real-time RT-PCR and HTS with Ion Torrent PGM detected the presence of dengue virus serotype 2(DENV-2).A clinical DENV-2 isolate GZ05/2014 was obtained by culturing the patient serum in mosquito C6/36 cells.The complete genome of GZ05/2014 was determined and deposited in Gen Bank under the access number KP012546.Phylogenetic analysis based on the complete envelope gene showed that the newly DENV-2 isolate belonged to Cosmopolitan genotype and clustered closely with other Guangdong strains isolated in the past decade.No amino acid mutations that are obviously known to increase virulence or replication were identified throughout the genome of GZ05/2014.The high homology of Guangdong DENV-2 strains indicated the possibility of establishment of local DENV-2 circulation in Guangdong,China.These results help clarify the origin of this epidemic and predict the future status of dengue in China.     

Sustainable harvesting and conservation of Laelia furfuracea,a rare epiphytic orchid from Oaxaca,Mexico

Many epiphytic orchids are harvested in Mexico for different purposes. Laelia furfuracea is one of the most intensively traded species. Its inflorescences are used as ornaments during the December festivities. We investigated the effect of severing the flowering pseudobulb. This is the traditional technique frequently used by collectors at the study area. We wished to investigate its effects on the production of new pseudobulbs, as well as on their size and flowering probability. Also, we examined the survival probability and growth of individuals that had fallen on the ground to evaluate their potential as trading resources. Inflorescence collection did not affect the production of new pseudobulbs the following season. However, it affected the size of these pseudobulbs, as well as their flowering probability. Yet, the direction of this effect was not consistent between years. Nearly six percent of all L. furfuracea plants at the study site were found on the ground. Over 80 percent of them survived for at least two years, although most of them showed pseudobulb loss over that period of time. We conclude that harvesting of flowering pseudobulbs may be sustainable in terms of its effects on plant performance, at least in the short term. The active management of plants that have fallen on the ground may reduce the harvesting pressure on natural populations. Harvesting of flowering pseudobulbs may diminish some aspects of plant performance, but its effects need to be evaluated with complete life cycle data and take into account interannual variation in vital rates. Abstract in Spanish is available with online material     

Characterization of antibody responses to combinations of a dengue virus type 2 DNA vaccine and two dengue virus type 2 protein vaccines in rhesus macaques

We evaluated three nonreplicating dengue virus type 2 (DENV-2) vaccines: (i) a DNA vaccine containing the prM-E gene region (D), (ii) a recombinant subunit protein vaccine containing the B domain (i.e., domain III) of the E protein as a fusion with the Escherichia coli maltose-binding protein (R), and (iii) a purified inactivated virus vaccine (P). Groups of four rhesus macaques each were primed once and boosted twice using seven different vaccination regimens. After primary vaccination, enzyme-linked immunosorbent assay (ELISA) antibody levels increased most rapidly for groups inoculated with the P and DP combination, and by 1 month after the second boost, ELISA titers were similar for all groups. The highest plaque reduction neutralization test (PRNT) titers were seen in those groups that received the DR/DR/DR combination (geometric mean titer [GMT], 510), the P/P/P vaccine (GMT, 345), the DP/DP/DP combination (GMT, 287), and the R/R/R vaccine (GMT, 200). The next highest titers were seen in animals that received the D/R/R vaccine (GMT, 186) and the D/P/P vaccine (GMT, 163). Animals that received the D/D/D vaccine had the lowest neutralizing antibody titer (GMT, 49). Both ELISA and PRNT titers declined at variable rates. The only significant protection from viremia was observed in the P-vaccinated animals (mean of 0.5 days), which also showed the highest antibody concentration, including antibodies to NS1, and highest antibody avidity at the time of challenge.     

Prevalence of Demodex mites in eyelashes among people of Oaxaca, Mexico

This study was carried out to determine the prevalence of Demodex mites in eyelashes of people from different places from Oaxaca. One thousand and ten patients underwent epilation of eight eyelashes from each eye and they were processed to search Demodex which was found in 208 (20%) of the patients and among them male was more affected than female, 119 (57%) and 89 (43%), respectively. There was not found a relationship between clinical manifestations among these patients since 101 (49%) and 107 (51%) of them were symptomatic and asymptomatic, respectively. The range of age that was more affected was 96-105 (100%), followed by 86-95 (75%) and 76-85 (64%) years old. The less affected were individuals of 15-25 years old (11%). Demodex folliculorum was relatively high in the eyelashes of individuals in young and old people in the rural region studied. These people are generally the most vulnerable patients because they live in overcrowded conditions and poor hygiene which facilitates the direct infection. Demodex brevis was found in only one sample.     

Elevation gradients of diversity for rodents and bats in Oaxaca, Mexico

1  This study documents patterns of rodent and bat diversity related to abiotic and biotic factors along elevational gradients in the Sierra Mazateca (640–2600 m a.s.l.) and Sierra Mixteca (700–3000 m a.s.l.) in Oaxaca, Mexico.
2  The two transects share similar faunas: 17 and 23 rodent species were captured in the sierras Mazateca and Mixteca, respectively, 14 of which occurred on both transects. Rodent species richness was similar in the wet season and the dry season along both transects. Rodent species richness peaked at 1025–1050 m in tropical semi-deciduous forest on both transects. Endemic species were restricted to high-elevation habitats.
3  Sixteen and 17 bat species were captured in the sierras Mazateca and Mixteca, respectively; 11 occurred on both transects. Bat species richness was higher in the wet season than in the dry season in the Sierra Mazateca. Bat species richness peaked at 1850 m in pine–oak forest in the Sierra Mazateca, and at 750 m and 1050 m in tropical semi-deciduous forest in the Sierra Mixteca, decreasing abruptly at higher elevations on both transects.
4  Patterns of trophic diversity of rodents and bats coincided with those of species richness on each transect. Species richness increased with increasing habitat diversity; increased with increasing rainfall and productivity; increased with increasing resource diversity; and increased in areas with high rates of speciation (rodents only).
5  The need for conservation action in Oaxaca is urgent and proponents should promote establishment of protected areas linking lowland habitats with high species richness to high-elevation habitats harbouring large numbers of endemic forms.     

Health and agricultural intensification in the prehistoric Valley of Oaxaca, Mexico

The effects of agricultural intensification on health are examined in prehistoric populations of the Valley of Oaxaca, Mexico. Agriculture was practiced in the Valley of Oaxaca by the beginning of the Early Formative period (ca. 1400 B.C.), and had intensified by the Late Formative (ca. 500 B.C.). Skeletal remains from 14 archaeological sites in the Valley are pooled by temporal affiliation into a nonintensive agriculture group (1400-500 B.C.) and an intensive agriculture group (500 B.C.-1400 A.D.). The health effects of agricultural intensification are assessed by comparing the frequency of periosteal reactions, cribra orbitalia, and enamel hypoplasia between the intensive and nonintensive agricultural groups. Overall, no significant differences (alpha = 0.05) are found between the nonintensive and intensive groups. Power analyses of the chi-square tests indicate that the tests have a high probability of rejecting a false null hypothesis. The intensification of agriculture does not appear to have had a deleterious effect on the health of the prehistoric population of the Valley. The differences between this study and previous studies of health and agricultural development may be explained by differences between the processes of intensification and development or by differences between primary and secondary centers of agricultural development.