Phaeohyphomycosis caused by Cladosporium bantianum in Kerala (India)

A case of phaeohyphomycosis caused by Cladosporium bantianum is reported from India for the first time. It is also the first known case of infection involving the foot caused by this fungus. The cultural characteristics and animal pathogenicity of the isolate are described.     

Effect of inoculum rate on mycorrhizal growth responses in pot-grown onion and clover

Summary White clover and onion plants were grown from seed in pots of sandy loam above pads of mycorrhizal inoculum soil at 0.17–1.40 g/pot (equivalent to 250–2000 kg/ha) and harvested on four occasions. In sterilized soil increasing inoculum rates increased the onset and size of the mycorrhizal growth response of white clover. In unsterilized soil the indigenous mycorrhizal fungi greatly stimulated growth of both clover and onion. Nevertheless, all mycorrhizal inoculum rates further stimulated shoot growth in onion (92% increase over all harvests), while only the highest inoculum rate significantly stimulated clover growth (52% increase).     

Effect of a steroidal oral contraceptive on intestinal absorptive functions in proteins deficient rat

The effects of steroidal oral contraceptive norethynodrel plus ethinylestradiol-3-methyl ether (SOC) at a daily dose of 5 mg: 0.06 mg per kg body weight for 28 days on intestinal absorptive functions have been investigated in protein-deficient female albino rats. The administration of this contraceptive caused significant increase in glucose and amino acids uptake but had no effect on calcium and zinc uptake in pair-fed as well as in protein-deficient rat. Further studies carried out on glucose transport system showed that the transport of sodium-dependent glucose was significantly enhanced while that of sodium-independent glucose remained unaltered in drug-treated animals. Kinetic studies of glucose transport in the presence of sodium ions revealed that SOC treatment affected the rate of uptake of glucose by elevating Vmax, but the apparent Kt value remained the same in treated and untreated animals.     

Kinetics of propylene glycol elimination and metabolism in rat

The kinetics of 1,2-propanediol (PD) metabolism in vivo have been determined by employing the Michaelis-Menten rate equation; it was found that maximum metabolizing capacity was 8.33 mmole PD/kg/hr in the rat, which is equivalent to 1.06 kg/day for an average 70-kg human. The rate equation could be suitably used for optimizing the dosage schedule of a drug from the linear elimination pattern; in the present case this gave a Km value of 17.86 mmole/kg on the basis of the elimination rate of PD. The competitive inhibition of PD elimination by preadministration of pyrazole (Ki = 44 mumole/kg) demonstrated that the first step of the biotransformation of PD catalyzed by the NAD-dependent dehydrogenase might be the rate-limiting step for its in vivo metabolism. The low threshold level of the compound and significant rate of metabolism suggested that the CNS toxicity reported in clinical studies might be due to some of its metabolites such as lactaldehyde and other oxo compounds. Thus, PD could not be considered as an inert and innocuous substance.     

Schistosoma mansoni enhances host susceptibility to mucosal but not intravenous challenge by R5 Clade C SHIV

Background

The high prevalence of HIV-1/AIDS in areas endemic for schistosomiasis and other helminthic infections has led to the hypothesis that parasites increase host susceptibility to immunodeficiency virus infection. We previously showed that rhesus macaques (RM) with active schistosomiasis were significantly more likely to become systemically infected after intrarectal (i.r.) exposure to an R5-tropic clade C simian-human immunodeficiency virus (SHIV-C) than were parasite-free controls. However, we could not address whether this was due to systemic or mucosal effects. If systemic immunoactivation resulted in increased susceptibility to SHIV-C acquisition, a similarly large difference in host susceptibility would be seen after intravenous (i.v.) SHIV-C challenge. Conversely, if increased host susceptibility was due to parasite-induced immunoactivation at the mucosal level, i.v. SHIV-C challenge would not result in significant differences between parasitized and parasite-free monkeys.

Methods and Findings

We enrolled two groups of RM and infected one group with Schistosoma mansoni; the other group was left parasite-free. Both groups were challenged i.v. with decreasing doses of SHIV-C. No statistically significant differences in 50% animal infectious doses (AID₅₀) or peak viremia were seen between the two groups. These data strongly contrast the earlier i.r. SHIV-C challenge (using the same virus stock) in the presence/absence of parasites, where we noted a 17-fold difference in AID₅₀ and one log higher peak viremia in parasitized monkeys (P<0.001 for both). The lack of significant differences after the i.v. challenge implies that the increased host susceptibility is predominantly due to parasite-mediated mucosal upregulation of virus replication and spread, rather than systemic effects.

Conclusions

The major impact of schistosome-induced increased host susceptibility is at the mucosal level. Given that >90% of all new HIV-1 infections worldwide are acquired through mucosal contact, parasitic infections that inflame mucosae may play an important role in the spread of HIV-1.     

Development of 22 new microsatellite loci for fishers (Martes pennanti) with variability results from across their range

We developed 22 new microsatellite loci for the fisher (Martes pennanti), a North American mesocarnivore. The loci were developed with samples from the southern Sierra Nevada Mountains in California, and were screened with samples from this population and four other populations. We observed a range of six to 21 polymorphic loci per population, with the Sierra Nevada population exhibiting markedly lower levels of variation compared to the other four.     

Cloning and characterization of 29 tetranucleotide and two dinucleotide polymorphic microsatellite loci from the endangered marbled murrelet (Brachyramphus marmoratus)

We developed 31 novel, polymorphic microsatellite loci in the marbled murrelet (Brachyramphus marmoratus), a critically endangered seabird. Variability was tested on 15 individuals from the Santa Cruz, California population, with each locus characterized by two to 12 alleles. Observed levels of heterozygosity ranged from 0.13 to 0.93. These loci provide a valuable means of assessing the population structure and demographic parameters of this species, which may be critical to its conservation across a fragmented habitat.     

Preservation of fresh edible cactus stems (<i>Opuntia ficus indica</i> Mill.) by modified atmosphere packaging

Cactus stems, the cladodes of Opuntia spp. cacti, are consumed in Mexico and other countries due to their fresh and herbaceous flavor, and because of their widely known nutraceutical benefits. In order to extend the postharvest life of this vegetable, the effect of a modified atmosphere packaging (MAP) was studied in cactus stems of the cultivar Atlixco stored at 4 ± 1 °C for 20 days under three types of atmospheres: (1) air (passive atmosphere), (2) 5 kPa O₂ + 4 kPa CO₂, and (3) N₂. During storage, the titratable acidity decreased and the color of cladodes became darker and less green; however, the 5 kPa O₂ + 4 kPa CO₂ atmosphere was able to preserve both quality characteristics. All modified atmospheres reduced weight loss (from 8 to <2%) and the symptoms of chilling injury, and this physiological disorder appeared earlier in controls than in MAP-stored cladodes. The levels of fermentation metabolites were low in all three evaluated atmospheres. Because of this, only cladodes stored under the N₂ atmosphere were selected for furthersensory analysis of the MAP effect on odor perception as evaluated by a trained panel. Results indicated that there was no detrimental effect (atypical odors) of MAP on this sensory characteristic. We conclude that cultivar Atlixco is suitable for preservation using MAP technology.