Survey of the mycoflora and mycotoxins of cotton seeds and cotton seed products in Egypt

Thirty-nine species and 16 fungal genera were isolated from Egyptian cotton seeds, cotton seed meal and cotton seed cake on 1% glucose-Czapek's agar medium incubated at 28 °C. Aspergillus was the most frequent genus and it emerged in 87–100% of the samples contributing 70–98% of total fungi in the three substrates tested. The most common species were A. niger, A. flavus, A. fumigatus, A. terreus and Rhizopus stolonifer; A. niger, A. fumigatus and Penicillium corylophilum; and A. niger, A. flavus, A. terreus, A. nidulans and Rhizopus stolonifer, respectively. Cotton seeds and cotton seed products were naturally contaminated by aflatoxin B₁ and B₂. About 16% of the different substrates tested were positive for aflatoxin contamination. No citrinin, ochratoxin A, patulin, sterigmatocystin, diacetoxyscirpenol, T-2 toxin or zearalenone were detected in the samples assayed.     

Biological Control of Macrophomina phaseolina Charcoal Rot of Sunflower and Mung Bean

Infection by Macrophonina phaseolina was substantially reduced following treatment of sunflower and mungbean seeds with Trichoderma harzianum, Gliocladium virens, Paecilomyces lilacinus or Streptomyces sp. which gave promising control of charcoal rot disease. Treatment of mungbean seeds with Rhizobium meliloti also gave good disease control.     

Electric shock-mediated transfection of cells. Characterization and optimization of electrical parameters.

The effect of various parameters on the electric shock-mediated permeabilization and transfection of CHO cells has been investigated. Up to 70% of the cells can be maintained transiently permeable to erythrosin B for periods of at least 1 h at 20 degrees C. Electrical conditions optimal for transient permeabilization were also optimal for efficient DNA transfection by pSV2neo. However, the DNA must be present during exposure to the electric field for efficient transformation. The same requirement existed for voltage-induced DNA toxicity. The results suggest that DNA moves into the cells by electrophoresis, not by simple diffusion. Based on these observations a simple, rapid procedure for optimizing the conditions for electric shock-mediated DNA transfer into cells has been developed.     

Facial clefts in Saudi Arabia: an epidemiologic analysis in 179 patients

One hundred and seventy-nine consecutive cases of facial clefts that were treated at the King Khalid University Hospital, in Riyadh, Saudi Arabia, were analyzed for an epidemiologic study. Isolated cleft lip was present in 38 percent, cleft of lip and palate in 37.4 percent, and cleft of the posterior palate in only 22.4 percent. There was a male preponderance in all types. In cases of cleft lip with or without cleft palate, the more commonly affected side was the left, followed by bilateral cases. Associated malformations were present in 13.4 percent. A positive family history was found in 26.8 percent of cases. A significant number of patients (7.8 percent) were first seen at more than 10 years of age. The incidence of facial clefts at this hospital was 0.3 per 1000 live births, computed over a period of 6 years. This incidence is significantly lower than that reported from European and Far Eastern countries.     

Triploidy induction in Nile tilapia,Oreochromis niloticus L. using pressure,heat and cold shocks

Summary The results of a study aimed at the identification of treatment optima for triploidy induction in recently fertilised Oreochromis niloticus L. eggs by altering the intensity, duration and timing of application of pressure, heat and cold shocks are reported. Preliminary, but not directly comparable, trials suggested the following treatments to be close to the individual agent optima. Pressure: 8,000 psi 2-min duration applied 9 min after fertilisation (a.f.); heat: 41 °C, 3.5-min duration applied 5 min a.f., cold: 9°C, 30-min duration applied 7 min a.f. In a directly comparable trial in which the eggs of eight different females were separately exposed to the optimum shocks listed above, individual triploid yields were more variable following cold shocks and mean triploid yields were, therefore, higher following pressure and heat shock. These and other results obtained are presented and the light they shed on the timing of the second meiotic division in this species is discussed.     

A new hominoid hamate and first metacarpal from the Late Miocene Nagri Formation of Pakistan

A hamate and the proximal part of a first metacarpal from the type locality of the Nagri Formation in Pakistan, and attributed to Sivapithecus parvada, are described. In overall proportions, the hamate is rather robust, showing most similarity to that of Gorilla. Unlike extant hominoids it lacks a well-developed hamulus, and its triquetral facet is morphologically dissimilar to that in extant anthropoids. The morphology of the hamate indicates effective weight transmission through the ulnar side of the wrist, limited ulnar deviation and restricted extension in the triquetrohamate joint, and stability of the hamatometacarpal joints. The morphology of the partial first metacarpal is most similar to that of Pan. Previously described postcranial bones of S. parvada indicate that its locomotor behaviour included both quadrupedalism and climbing. This is consistent with the limited evidence of the first metacarpal, whereas the hamate strongly emphasizes the quadrupedal aspect of the locomotor repertoire.     

Characterization of PDR4, a Saccharomyces cerevisiae gene that confers pleiotropic drug resistance in high-copy number: identity with YAP1, encoding a transcriptional activator [corrected

PDR4 is a gene that confers pleiotropic drug resistance (pdr) to the yeast Saccharomyces cerevisiae when present in high copy number [Leppert et al., Genetics 125 (1990) 13-20]. Transposon insertion mutations had identified the active region of the gene as a 3.7-kb SalI-EcoRI restriction fragment of the 8-kb cloned fragment. We have confirmed this by showing that this fragment is sufficient to confer pdr, and have sequenced its entire 3761 bp. It contains a single complete open reading frame (ORF) extending from nucleotide (nt) position 1631-3580, coding for a protein of 650 amino acids (aa). A 2.7-kb fragment containing this ORF is also sufficient to confer pdr. The aa sequence contains no recognizable homologies or consensus sequences, so it is a novel protein of unknown function. It is apparently soluble, since no transmembrane-type sequences were predicted. A second, partial ORF was also found, on the opposite strand, extending from nt position 774 to past the SalI site, which is apparently unrelated to pdr.     

IgE responses in human filariasis. IV. Parallel antigen recognition by IgE and IgG4 subclass antibodies

Immediate hypersensitivity responses are highly modulated in filariasis, and with few exceptions, the majority of infected individuals do not develop allergic manifestations. One possible mechanism for this modulated responsiveness could involve the high levels of IgG "blocking antibodies" shown to be present in filariasis and other chronic helminth infections. When immunoblot analyses were done to analyze the immunoglobulin (Ig) E and IgG antibody responses of patients simultaneously, remarkable similarity in the patterns of antigen binding was observed. In this study, the four IgG subclasses were analyzed in a similar manner in relation to IgE. The results clearly demonstrate that IgG4 was primarily responsible for this "parallel" recognition that was seen previously between IgG and IgE antibodies. These results lend additional support to the possibility that IgG4 may play an important role in modulating IgE-mediated allergic responses in vivo.     

Cytochemical localization of 5'-nucleotidase in the frog (Rana pipiens) retina. A histochemical and cytochemical study

Localization of 5'-nucleotidase in the frog retina was investigated using histochemical and cytochemical techniques. Light-microscopic observations revealed the presence of this enzyme in the inner retinal layers (the nerve fiber layer, ganglion cell layer, and inner plexiform layer). Ultrastructural investigations revealed that the enzyme activity is associated with the plasma membranes of the Müller cell processes, whereas the Müller cell processes present in the outer retinal layers did not demonstrate any detectable enzyme activity. This observation would appear to confirm our previous findings, that 5'-nucleotidase is an ectoenzyme, but its distribution in frog retina differs from that in rodents and it is only present in the inner layers of the retina. The prominent localization of 5'-nucleotidase on the glial plasma membrane may be viewed in the context of the widely accepted interaction between neurones and glial cells. Since nucleotides do not penetrate the plasma membrane, a mechanism to produce membrane-permeable adenosine, important for neuronal function, is postulated. It is known that 5'-nucleotidase produces adenosine by hydrolyzing adenosine 5'-monophosphate (5'-AMP). Therefore one would expect that the glial membrane-bound enzyme can accomplish the final step in this mechanism by producing the adenosine in the extracellular spaces.     

Changes in collagen and albumin mRNA in liver tissue of mice infected with Schistosoma mansoni as determined by in situ hybridization

We have employed in situ hybridization to evaluate the molecular mechanisms responsible for hypoalbuminemia and increased liver collagen content in murine schistosomiasis. Results were compared using a simplified method of hybridizing isolated hepatocytes from Schistosoma mansoni-infected and normal mouse liver with mouse albumin (pmalb-2) and chick pro-alpha 2(l) collagen (pCg45) probes. Whereas hepatocytes from infected mice showed significantly less albumin mRNA than hepatocytes from control, there were more grains of procollagen mRNA in hepatocytes from infected as compared with control liver. Hybridization of infected liver tissue sections with the collagen probe showed more grains per field in granulomas than in liver regions, whereas with the albumin probe there was more hybridization in liver tissue than in granulomas. These results suggest that in murine schistosomiasis a reduction in albumin mRNA sequence content may be associated with decreased albumin synthesis and ultimately leads to hypoalbuminemia. In addition, although the granuloma seems to be the primary source of type I collagen synthesis, hepatocytes are also capable of synthesizing collagen, especially under fibrogenic stimulation.