香菇的学名及其在当代真菌分类中的位置

本文综述了香菇(Lentinula edodes)的分类历史,确认其在蘑菇目(Agaricales)Tricholomataceae科下的分类地位,并证实了它与多孔菌目(Poriales)Lentinaceae科的Lentinus属没有联系。根据《真菌、地衣汉语学名命名法规》,作者讨论了译为“香菇属”的Lentinus和“小香菇属”的Lentinellus两属的汉语学名问题,提出Lentinus的汉语学名应订正为“韧伞属”,Lentinellus为“螺壳菌属”。香菇所在的Lentinula属的汉语学名建议为“木菇属”。     

Microgametophytic plastid nucleoid content and reproductive and life history traits of tribeTrifolieae (Fabaceae)

Microgametophytic plastid nucleoids were quantified for 18 species representing the four core genera of the tribeTrifolieae (Fabaceae),Medicago, Melilotus, Trigonella, andTrifolium. Generative cells of all taxa contained nucleoids, establishing that biparental plastid inheritance is common in theTrifolieae. Nucleoid number and volumes of pollen grains and generative cell nuclei differed among taxa. Nucleoid number was positively correlated with pollen grain and generative cell nuclear volumes, flower size and style length. These relationships disappeared after adjusting nucleoid number for pollen grain and generative cell nuclear volumes. Adjusted nucleoid numbers provided no evidence to support hypotheses that plastid content is associated with ploidy level, mating system, perenniality or size of the reproductive apparatus.     

Cross-species amplification of soybean (Glycine max) simple sequence repeats (SSRs) within the genus and other legume genera: implications for the transferability of SSRs in plants

We investigated the transferability of 31 soybean (Glycine max) simple sequence repeat (SSR) loci to wild congeners and to other legume genera. Up to 65% of the soybean primer pairs amplified SSRs within Glycine, but frequently, the SSRs were short and interrupted compared with those of soybeans. Nevertheless, 85% of the loci were polymorphic within G. clandestina. Cross-species amplification outside of the genus was much lower (3%-13%), with polymorphism restricted to one primer pair, AG81. AG81 amplified loci in Glycine, Kennedia, and Vigna (Phaseoleae), Vicia (Vicieae), Trifolium (Trifolieae), and Lupinus (Genisteae) within the Papilionoideae, and in Albizia within the Mimosoideae. The primer conservation at AG81 may be explained by its apparent proximity to the seryl-tRNA synthetase gene. Interspecific differences in allele size at AG81 loci reflected repeat length variation within the SSR region and indels in the flanking region. Alleles of identical size with different underlying sequences (size homoplasy) were observed. Our findings and the emerging patterns in other plant studies suggest that in contrast to animals, successful cross-species amplification of SSRs in plants is largely restricted to congeners or closely related genera. Because mutations in both the SSR region and the flanking region contribute to variation in allele size among species, knowledge of DNA sequence is essential before SSR loci can be meaningfully used to address applied and evolutionary questions.      

Effect of indomethacin and prostaglandin E2 on structural differentiation of rat endometrium during artificially induced decidualization

Morphological differentiation of uterine stromal and luminal epithelial cells was studied in steroid-injected ovariectomized rats following unilateral intrauterine instillation of sesame oil, phosphate-buffered saline containing gelatin (PBSG), PBSG + indomethacin (IM; an inhibitor of prostaglandin synthesis), or PBSG + IM + prostaglandin E2 (PGE2). The latter two treatments were preceded by a subcutaneous injection of IM. Uteri were examined by light and electron microscopy at intervals between 8 and 120 hr (n = 4/treatment/time). Differentiation began in the periluminal antimesometrial region and progressed peripherally and towards the mesometrial aspect in all groups. Structural features and timing of differentiation were similar for oil-injected and PBSG-infused uteri. Administration of IM inhibited the onset of the decidual cell reaction and had deleterious effects on the luminal epithelium. Inclusion of PGE2 in the instillate accelerated stromal cell differentiation and overcame the inhibitory effect of IM. The results implicate prostaglandins, particularly PGE2, in endometrial transformation during decidualization.     

A new repetitive element of the CR1 family downstream of the chicken vitellogenin gene.

We have analyzed a repetitive DNA sequence found in the 3'-flanking region of the chicken vitellogenin gene. By its sequence, the repetitive DNA has been identified as a hitherto unreported member of the chicken CR1 family of repetitive elements. The CR1 sequence displays the structural characteristics of a long terminal repeat located at the 3' end of an avian retrovirus. The CR1 element lies 2.2 kb downstream of the vitellogenin gene and 'points' away from the gene rather than toward it. In this respect, this element differs from other CR1 repeats. The CR1 element is embedded in a region showing changes in chromatin structure implying a potential role for this sequence in determining the structural state of the local chromatin.     

On the Evolutionary History,Population Genetics and Diversity among Isolates of Salmonella Enteritidis PFGE Pattern JEGX01.0004

Facile laboratory tools are needed to augment identification in contamination events to trace the contamination back to the source (traceback) of Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis). Understanding the evolution and diversity within and among outbreak strains is the first step towards this goal. To this end, we collected 106 new S. Enteriditis isolates within S. Enteriditis Pulsed-Field Gel Electrophoresis (PFGE) pattern JEGX01.0004 and close relatives, and determined their genome sequences. Sources for these isolates spanned food, clinical and environmental farm sources collected during the 2010 S. Enteritidis shell egg outbreak in the United States along with closely related serovars, S. Dublin, S. Gallinarum biovar Pullorum and S. Gallinarum. Despite the highly homogeneous structure of this population, S. Enteritidis isolates examined in this study revealed thousands of SNP differences and numerous variable genes (n = 366). Twenty-one of these genes from the lineages leading to outbreak-associated samples had nonsynonymous (causing amino acid changes) changes and five genes are putatively involved in known Salmonella virulence pathways. While chromosome synteny and genome organization appeared to be stable among these isolates, genome size differences were observed due to variation in the presence or absence of several phages and plasmids, including phage RE-2010, phage P125109, plasmid pSEEE3072_19 (similar to pSENV), plasmid pOU1114 and two newly observed mobile plasmid elements pSEEE1729_15 and pSEEE0956_35. These differences produced modifications to the assembled bases for these draft genomes in the size range of approximately 4.6 to 4.8 mbp, with S. Dublin being larger (∼4.9 mbp) and S. Gallinarum smaller (4.55 mbp) when compared to S. Enteritidis. Finally, we identified variable S. Enteritidis genes associated with virulence pathways that may be useful markers for the development of rapid surveillance and typing methods, potentially aiding in traceback efforts during future outbreaks involving S. Enteritidis PFGE pattern JEGX01.0004.     

The intracellular distribution of free nucleotides in the tobacco leaf. Formation of adenosine 5′-phosphate from adenosine 5′-triphosphate in the chloroplasts

1. A method of studying the free nucleotides of leaf tissue is outlined and the need for a metal ion-binding agent for the complete extraction of certain nucleotides by aqueous ethanol is established. 2. The method was used to study the effect of illumination or darkening of tobacco plants on the free nucleotides present in the chloroplast and non-chloroplast tissue components. 3. When plants that had been in the dark for a prolonged period were given 30sec. of bright light there was a rapid phosphorylation of ADP to ATP in both chloroplast and non-chloroplast components of the tissue. 4. Where plants were moved into the dark from conditions suitable for rapid photosynthesis there was a rapid conversion of ATP into AMP and the AMP was formed only in the chloroplast fraction. In continuing darkness the AMP remained restricted mainly to the chloroplast fraction for at least 2min., but eventually its concentration fell to the low value that is typical of tobacco leaves during conditions of constant illumination. If the plants were returned to the light for 30sec. the AMP was rapidly rephosphorylated.     

Reflechi twòp—Thinking Too Much: Description of a Cultural Syndrome in Haiti’s Central Plateau

A rich Haitian ethnopsychology has been described, detailing concepts of personhood, explanatory models of illness, and links between mind and body. However, little research has engaged explicitly with mental illness, and that which does focuses on the Kreyòl term fou (madness), a term that psychiatrists associate with schizophrenia and other psychoses. More work is needed to characterize potential forms of mild-to-moderate mental illness. Idioms of distress provide a promising avenue for exploring common mental disorders. Working in Haiti’s Central Plateau, we aimed to identify idioms of distress that represent cultural syndromes. We used ethnographic and epidemiologic methods to explore the idiom of distress reflechi twòp (thinking too much). This syndrome is characterized by troubled rumination at the intersection of sadness, severe mental disorder, suicide, and social and structural hardship. Persons with “thinking too much” have greater scores on the Beck Depression Inventory and Beck Anxiety Inventory. “Thinking too much” is associated with 8 times greater odds of suicidal ideation. Untreated “thinking too much” is sometimes perceived to lead to psychosis. Recognizing and understanding “thinking too much” may allow early clinical recognition and interventions to reduce long-term psychosocial suffering in Haiti’s Central Plateau.