Stephen R. Anderson

Prevention of diabetic glomerulopathy by pharmacological amelioration of glomerular capillary hypertension.

Two groups of adult male Munich-Wistar rats and a third group of nondiabetic age-matched and weight-matched normal control rats underwent micropuncture study 1 mo, and morphologic studies 14 mo, after induction of streptozotocin diabetes or sham treatment. All animals were fed standard rat chow. Diabetic rats received daily ultralente insulin to maintain stable moderate hyperglycemia (approximately 350 mg/dl). In addition, one group of diabetic rats was treated with the angiotensin I converting enzyme inhibitor, enalapril, 15 mg/liter of drinking water. Average kidney weight, whole kidney and single-nephron glomerular filtration rate, and glomerular plasma flow rate were elevated to similar values in both groups of diabetic rats, relative to normal control rats. Non-enalapril-treated diabetic rats exhibited significant elevations in mean glomerular capillary hydraulic pressure and transcapillary hydraulic pressure gradient, compared with the other groups studied, and only this group eventually developed marked and progressive albuminuria. Likewise, histological examination of the kidneys at 14 mo disclosed a high incidence of glomerular structural abnormalities only in non-enalapril-treated diabetic rats. These findings indicate that prevention of glomerular capillary hypertension in rats with diabetes mellitus effectively protects against the subsequent development of glomerular structural injury and proteinuria. This protection is afforded despite pronounced hyperglycemia and elevated levels of glucosylated hemoglobin, further supporting our view that hemodynamic rather than metabolic factors predominate in the pathogenesis of diabetic glomerulopathy.

Nasal Consonants and the Internal Structure of Segments

Phonetic theory has generally been based on the assumption that speech can be divided into discrete segments, each phonetically homogeneous with respect to all linguistically significant parameters. Among the nasal consonants, however, are segments which must have internal sequential structure. Primary nasal consonants are first discussed here, and it is concluded that these should be described as non-continuants. Various possible characterizations of complex nasal segments (preand post-nasalized stops) are then considered, and it is concluded that no feature homogeneous over the segment is adequate to describe them. The conclusion that these segments involve internal sequencing suggests that rules should exist which can produce and manipulate such intra-segmental structure. Applications of such rules are briefly suggested.*

Disjunctive ordering in inflectional morphology

ConclusionAt a minimum, the discussion above ought to have the effect of convincing the reader that the facts of natural language morphologies are as predicted by a theory of disjunctive organization based on principles (3) and (4) proposed in the introduction. In some cases, such a theory allows us to bring much more coherence to our account of the facts than seems possible on a more traditional, morpheme-based account, as with the analysis of Georgian -t in section 1. In others, superficial counterexamples to the theory, such as those examined in section 2, turn out on closer examination to be consistent with it after all, as shown in section 3. More important than the demonstration that particular examples can be given analyses (often ones that are superior to those otherwise available) within this theory, however, is another consideration. In each case above, the theory of disjunctive ordering itself suggested problems and lines of research that might not otherwise have been apparent, and which proved interesting and useful to investigate. It is thus not only a candidate for part of the theory of morphological structure, but also a productive research strategy for the investigation of such systems. Based as it is on the construal of morphology as a system of interacting rules expressing relations between forms, rather than as an inventory of unitary and meaningful ‘morphemes’, it supports the general utility of this larger view.

How to Get even

Various proposals for treating the word even in a transformational grammar of English are reviewed. It is shown that the word cannot be derived from a structure in which it is directly associated with that portion of the sentence which constitutes its semantic scope. An alternative account based on principles of interpretation of derived structure is sketched and motivated. The semantic content of the word is suggested as the source of limitations on its appearance within the sentence.*

On the interaction of phonological rules of various types

Discussions of linguistic structure generally accept a distinction between rules of sentence structure and rules of sound structure, but there is very little agreement on further subcategorization beyond this general dichotomy. Indeed, recent discussion in the area of syntax and semantics has been dominated, at least superficially, by the question of whether it is possible and/or desirable to distinguish within the rules of sentence structure between syntactic rules and semantic rules, and perhaps to impose further subcategorizations on each of these; see, for example, the contributions by Chomsky and Postal to Peters (1972). Within syntax and semantics, however, there is probably much less disagreement than meets the eye: most would agree that a desirable goal for linguistics is to isolate and distinguish as many types of rule as possible, and to associate each type with a set of maximally restrictive formal and substantive constraints.1 Although much less attention has been concentrated on this issue in phonology in recent years, the tradition of structuralist or autonomous phonemics took fairly explicit positions on a number of issues concerning the possibility of subdividing the study of sound structure. Figure [i] is a composite representation of the internal organization of that part of a structuralist grammar which deals with phenomena below the level of word structure: Thus, on this view, the conversion of a morphemic representation into sound involves two distinct intermediate levels: a level of morphophonemic representation (for those who believed in the utility of morphophonemics), and a (taxonomic or autonomous) phonemic representation. Each is defined by the set of rules which relate it to those on either side. Since Halles celebrated argument against the phoneme was first presented in the late 1950s, generative phonologists have generally felt that they had freed themselves from the strictures imposed by the positing of such intermediate levels. Halle demonstrated, that is, that a representation with the characteristics of the autonomous phonemic level could not be maintained as a condition of adequacy for grammars, since this would lead to a loss of generalization in the description of sound structure. The same rule would sometimes have to be

RNA primers in simian virus 40 DNA replication: II. Distribution of 5′ terminal oligoribonucleotides in nascent DNA

Abstract A cell-free simian virus 40 (SV40) DNA replication system served to study the role of RNA in the initiation of nascent DNA chains of less than 200 nucleotides (Okazaki pieces). RNA-DNA covalent linkages were found to copurify with SV40 replicating DNA. These linkages were identified by transfer of a fraction of the 32P from the 5′ position of a deoxyribonucleotide to 2′(3′)rNMPs upon either alkaline hydrolysis or RNAase T2 digestion of SV40 replicating [32P]DNA. Alkaline hydrolysis also exposed 5′ terminal hydroxyl groups in the nascent DNA which were detected as nucleosides after digestion with P1 nuclease. The RNA-DNA covalent linkages resulted from a population of Okazaki pieces containing uniquely sized oligoribonucleotides covalently attached to their 5′ termini (RNA primers). The density of a portion of the Okazaki pieces in potassium iodide gradients corresponded to a content of 90% DNA and 10% RNA, while the remaining Okazaki pieces appeared to contain only DNA. Incubation of Okazaki pieces with a defined length in the presence of either RNAase T2 or potassium hydroxide converted about one-third to one-half of them intto a second well defined group of DNA chains of greater electrophoretic mobili y in polyacrylamide gels. The increased mobility corresponded to the removalof at least seven-residues. Since alkaline hydrolysis of similar Okazaki pieces revealed that one-third to one-half of them contained rN-32P-dN linkages, the oligoribonucleotides must be covalently attached to the 5′ ends of nascent DNA chains. Although the significance of two populations of Okazaki pieces, one with and one without RNA primers, is imperfectly understood, a sizable fraction of nascent DNA chains clearly contained RNA primers. Neither the length of the RNA primer nor the number of RNA primers per DNA chain changed significantly with increasing length of Okazaki pieces. Since the frequency of RNA-DNA junctions found in nascent DNA chains greater than 400 nucleotides was similar to that of Okazaki pieces, the complete excision of RNA primers appears to occur after Okazaki pieces are joined to the 5′ end of growing daughter strands. 32P-label transfer analysis of Okazaki pieces recovered from hybrids with isolated HindII + III restriction fragments of SV40 DNA revealed a uniform distribution of rN-P-dN sequences around the replicating DNA molecule. Therefore, most, if not all, RNA primers serve to initiate Okazaki pieces rather than to initiate DNA replication at the origin of the genome. Moreover, the positions of RNA primers are not determined by a specific set of nucleotide sequences.

THE TYPOLOGY OF ANAPHORIC DEPENDENCIES: ICELANDIC (AND OTHER) REFLEXIVES*

The properties of English reflexive pronouns have had a profound effect on the development of syntactic theory over the past twenty years or so. Hardly any presentation of a theoretical position, (at least) since Postal’s (1964) classic argument for the existence of transformations from the interaction of reflexives with imperative formation, is considered complete unless it provides an analysis of reflexives in English. The principles of the Government/Binding (GB) theory, in particular, rest centrally on the distinction between anaphors and non-anaphors, and thus on the properties of reflexives.

The Measurement of Outcome Variables in Couple and Family Therapy Research

Measurement constitutes a central issue in determining effectiveness of couple and family therapy (CFT). A review of 274 CFT outcome studies published in 25 mental health journals between 1990 and 2005 is presented. Goals of this review were to (1) provide a broad, empirically based overview of CFT outcome research, (2) examine measurement of treatment outcomes, and (3) appraise reporting practices. Findings indicate that a wide range of instruments continue to be used in CFT outcome research, although a foundation for a more integrated and coherent assessment battery has been established. Implications for the field are discussed.

Maturation of replicating simian virus 40 DNA molecules in isolated nuclei by continued bidirectional replication to the normal termination region

Mature SV40 DNA synthesized for different periods of time either in isolated nuclei or in intact cells was highly purified and then digested with restriction endonucleases in order to relate the time of synthesis of newly replicated viral DNA to its location in the genome. Replication in nuclei supplemented with a cytosol fraction from uninfected cells was a faithful continuation of the bidirectional process observed in intact cells, but did not exhibit significant initiation of new replicons. SV40 DNA replication in cells at 37 degrees C proceeded at about 145 nucleotides/min per replication fork. In the absence of cytosol, when DNA synthesis was limited and joining of Okazaki fragments was retarded, bidirectional SV40 DNA replication continued into the normal region where separation yeilded circular duplex DNA molecules containing one or more interruptions in the nascent DNA strands. In the presence of cytosol, this type of viral DNA was shown to be a precursor of covalently closed, superhelical SV40 DNA, the mature from of viral DNA.

Morphological universals and diachrony

We conclude that what we find in language is only partially explained by what is “natural.” Some things that we find in the morphology of a language are there not because the language faculty requires them but because change tends to create them for independent reasons; while some things that are rare or perhaps even non-existent are not to be found because there are few if any pathways that could produce them from an available source. These observations have surprisingly important consequences: they mean that our account of the human cognitive capacity for language cannot be based simply on generalizations about what we find in the languages of the world, or on what can be grounded in some other domain, such as phonetics. The cognitive capacity we hope to capture may well be much more flexible than we might think at first glance, and as a result, it may be considerably harder to determine its properties than has been assumed.