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Genetic analysis by PBS1 transduction has demonstrated that bacterial markers spanning the φ105 attachment site are spread upon integration, accounting for insertion of one or more φ105 genomes.

The chromosomal attachment site for the PA-2 prophage is located between dsd and aroC at the approximately 50 min on the Escherichia coli K-12 genetic map. The attachment site is designated attPA-2.

Successful mitosis depends critically on the segregation of chromosomes by kinetochore microtubules. A recent paper describes a conserved protein network from Caenorhabditis elegans that is composed of three classes of molecules, each of which contributes uniquely to the building of the kinetochore–microtubule attachment site.

Summary Temperate coliphage HK022 has 45 × 51 nm heads, 106 nm long, flexible tails, and linear DNA of 26.4 × 106 mol. wt. The prophage attachment site (atthtt ) is co-transducible with pyrD and is located between pyrD and pyrC.

Hyperparasitism is common in laboratory colonies of Egyptian Ornithodoros erraticus whether the ticks are on or off the rodent host. Sex, recent engorgement, and size appear to be major factors in this feeding relationship. Males, and nymphs that produced males (N-male), parasitized females and nymphs that produced females (N-female) more frequently than they parasitized males and N-male. Females and N-female seldom parasitized females and N-female and did not parasitize males or N-male. Engorging and recently engorged, large ticks attracted smaller unfed ones. No preferred attachment site was observed. Hyperparasitizing females and parasitized females weighed less, had a longer preoviposition period, and produced fewer eggs than normally feeding, unparasitized females. About 30% and 80% of the females parasitized by males and females, respectively, died within 3 mo; only 7% of unparasitized females died within the same period. The proximity of replete or engorging ticks may be sufficient stimulus for hyperparasitism. Additional factors may include production of an attracting kairomone by fed ticks or the absence under certain conditions of a deterrent to hyperparasitism normally produced by fed ticks. Borrelia crocidurae spirochetes are transmitted during hyperparasitism.

This case illustrates the potential severity of an uncommon and generally benign condition of the knee--the Pellegrini-Stieda syndrome. The regional bone scan clearly showed the etiologic role of the inflamed ligamentous attachment site. Therapy should include joint rest, nonsteroidal anti-inflammatory agents, and possibly ice for symptomatic relief.

After culture with 3H-thymidine murine erythroleukemia cells with more sites of DNA attached to the nuclear matrix have more labeled thymidine in their matrix-bound DNA than in their total DNA than do cells with fewer attachment sites. This indicates that the average attachment site sequence is enriched in A + T base pairs.

The large number of reconstructive procedures in the treatment of ACL reflect a lack of consistent clinical success, thus creating the current controversy over the treatment of ACL injuries. The purpose of this study on the relationship of the femoral attachment site to the isometric tracking of the ACL graft was three-fold: 1) to develop a method for evaluating the femoral attach ment site for the ideal isometric graft tracking pattern; 2) to develop a reference table comparing femoral attachment sites to graft excursion; and 3) to apply this information to the surgical procedure to allow for step wise refinement of the attachment site for improved clinical results. To aid in graphic representation, the attachment sites were identified from radiographs by the sclerotic margin of the drill hole in the bone or the bone trough. These attachment sites were transferred to a trace diagram and compiled to form a composite diagram. Three distinct graft tracking patterns were identified. Group I represented the modified "over-the-top" technique with a deep cancellous bone trough and represented the most isometric tracking. Group II represented the mod ified over-the-top technique with a shallow or no can cellous bone trough and Group III the drill hole tech nique. Groups II and III were nonisometric. In surgery, palpation of the graft for excursion while performing a range of motion allows for review of isometric graft tracking. Stepwise intraoperative refine ment of the femoral attachment site can result in iso metric graft tracking.

The attachment site for the prophage of SPbeta lies between ilvA and kauA on the chromosome of Bacillus subtilis strain 168. Specialized transduction of citK and kauA can be carried out by certain lysates of SPbeta.

A variety of novel transducing lines of phage lambda can be obtained by induction of a mixed culture of abnormal lysogens. Such a culture is simply made by mass lysogenization of a host lacking the normal prophage attachment site.

X-Ray diffraction data have been obtained for nine related antiviral agents ("WIN compounds") while bound to human rhinovirus 14 (HRV14). These compounds can inhibit both viral attachment to host cells and uncoating. To calculate interpretable electron density maps it was necessary to account for (1) the low (approximately 60%) occupancies of these compounds in the crystal, (2) the large (up to 7.9 A) conformational changes induced at the attachment site, and (3) the incomplete diffraction data. Application of a density difference map technique, which exploits the 20-fold noncrystallographic redundancy in HRV14, resulted in clear images of the HRV14:WIN complexes. A real-space refinement procedure was used to fit atomic models to these maps. The binding site of WIN compounds in HRV14 is a hydrophobic pocket composed mainly from residues that form the beta-barrel of VP1. Among rhinoviruses, the residues associated with the binding pocket are far more conserved than external residues and are mostly contained within regular secondary structural elements. Molecular dynamics simulations of three HRV14:WIN complexes suggest that portions of the WIN compounds and viral protein near the entrance of the binding pocket are more flexible than portions deeper within the beta-barrel.

Transducing lambda bacteriophages have been isolated which carry the divergently transcribed argECBH operon of E. coli K12 and various portions of the adjacent ppc and bfe chromosomal regions. They were recovered from lysates prepared by the procedure of Schrenk and Weisberg using a Ppc+ Arg+ Bfe+ strain carrying a deletion of the usual attachment site of lambda. Heteroduplex DNA mapping of these lumbdadarg and of the phi 80 darg isolated by B. Konrad indicates that the two kinds of phages carry the arg cluster in opposite orientations, a situation favorable for the isolation of argECBH DNA. A physical map of the ppc argECBH bfe region including 2 unusual attachment sites of lambda has been constructed. The localization of the end points of certain arg deletions provides a useful reference framework for the currently pursued mapping of mutations affecting the control of divergent transcription and for the location of restriction enzyme cleavage sites in the arg region.

White clover root hairs which were inoculated with Rhizobium trifolii 4S (infectious strain) contained infection threads which were observed by light microscopy and scanning electron microscopy. Three morphological types of root hairs retaining infection threads were recognized. The bacteria were strongly attached between the surfaces of two plant cell walls as follows: between surfaces of a root hair tip curled back on itself, between a protuberance from a root hair and its cell surface, or between two root hair tips clinging together. An anatomical analysis documented the attachment site of the infection thread sheath from the inside of the root hair cell.

During infection in mice Echinostoma caproni is attached to the mucosa of the small intestine with the ventral sucker (acetabulum). The morphology, histology and dynamics of attachment sites from primary infections were examined. The sites were highly characteristic microscopically, and consisted of a plug of grasped mucosa occupying the cavity of the ventral suckers. The mucosa in the area of the small intestine where the parasite resided showed marked villous atrophy and crypt hyperplasia. The cellular composition of the attachment sites did not appear significantly different from what was seen in other parts of the mucosa in the residential area, and the study did not reveal any specific cellular host response at the attachment site. After mechanical removal of the parasites from unfixed tissue in saline, the attachment sites gradually reduced in size and disappeared. It is suggested that the attachment sites are only temporary structures, formed by the mechanical grasp of the ventral sucker as the parasites move about in the residential area of the intestine.

In the reaction of Bos taurus cattle to infestation by the tick Boophilus microplus, mast cell histamine is translocated by the eosinophils to the attachment site. The concentration pattern of this cutaneous mediator for pain appears related to the grooming behaviour of the host.

Leftward transcription in the region of the left attachment site (att) has been found to be required for the excision of λ prophage, when a helper provides all the necessary excision proteins (Davies et al., 1972). That observation has allowed the discovery of another component in λ site-specific recombination. This additional component is revealed by deleting a part of the b2 region of the helper. It is asserted that the newly discovered function is an inhibitor of site-specific recombination. The effect of the two components, local transcription and the b2 inhibitor, has been further studied in the excision of prophages flanked by other than the normal pair of atts.

The objectives of this study are twofold. First, to further develop the understanding of the relationship between the observed mechanical response and changes in the crimp pattern in human patellar tendon bone units. This is accomplished through the use of a specially constructed test frame and microscope system that permits observation and measurement of the crimp patterns as a function of load. Second, the results of the experimental study are used to develop a constitutive equation that includes spatial variation in the crimp pattern. The results of both the experimental and analytical study imply that local strain in the proximity of the attachment site is significantly larger than the strain in the central region of the tendon. The experimental and histological results are for specimens taken from four human bone-patellar tendon-bone units.

Axial myopia is a common ocular problem characterized by the fact that the posterior sclera has apparently stretched out of shape over a period of several years. The debate persists as to whether myopia is an inherited or acquired disorder. During the last few years, several new laboratory techniques have surfaced which can create large amounts of myopia in normal experimental animals. In an attempt to find a mechanical explanation common to both human and laboratory myopia, this paper examines the stresses experienced by the posterior sclera as a result of accommodation, convergence, vitreous pressure, and the extraocular muscles. The conclusion is that convergence, and more generally, the tension in the extraocular muscles, are mechanically much more important than accommodation because of the sizeable increase in vitreous pressure. The oblique muscles, because of their attachment sites at the back of the globe near the optic nerve entrance port, have the capability of producing local stress concentrations which may be very important in understanding pathological myopia.

The gal - bio region was transduced from Escherichia coli B to K12 and lysogenized with λ b 2. By means of P1 transduction mapping, the λ b 2 prophage was shown to be inserted between gal and bio and to be circularly permuted in the same way as λ b 2 + in K12. Increased frequency of recombinations within the prophage was observed when the viral genes were mapped with respect to bio instead of to gal . The results are interpreted to indicate the existence of a region in λ situated close to the b 2 region and homologous with a λ attachment site of E. coli B but not with that of E. coli K12.

The attachment site on the Bacillus subtilis chromosome for the lysogenic bacteriophage SPO2 has been mapped by PBS1-mediated transduction and was found to be between spc-2 and lin-2 , showing 90% linkage to the former and 30% linkage to the latter marker. In the course of these studies the bry-2 marker was mapped between the cysA14 and str-1 loci.

Thirty-seven amber and 3 thermosensitive mutants of the temperate phage Mu-1 were isolated and assigned to 15 different cistrons. The markers were ordered by deletion mapping in two independently isolated Mu lysogens. The same order was found in both cases. This order is the same as the order found by other authors (see accompanying papers), indicating that Mu has a unique attachment site on its DNA.

When a P2 prophage in location H is contransduced with his or when a P2 in location I is cotransduced with metG by P1 transduction, heterogenotic transductants are formed. The transduced genes and the prophage are integrated in the recipient chromosome in tandem with the homologous bacterial genes. Integration is rec dependent. Loss of one of the sets of genes can occur either by a phage int-dependent event or by rec-promoted haploidization. The phage attachment site is altered in the process of heterogenote formation.

Spinae are attached to protease-sensitive structural proteins in the external surface of the outer membrane. Agents and (or) treatments affecting ionic, hydrophobic, or hydrogen bonds are ineffective in releasing spinae from bacteria. As judged by thin-sectioning and freeze-fracturing techniques, the outer membrane is not modified at the attachment site to a detectable extent, and the other surface layers are not involved. The attachment of spinae is thus differentiated from that of flagella.

Pseudoscorpions of the genus Cheiridium were found phoretic on adult Anopheles freeborni (1♀) and Culex tarsalis (5♂, 2♀) collected from shelters and CO2 light traps operated in Kern County, California, USA, during 1983. Cheiridium sp. characteristically attach themselves tightly against the venter of the first 2 abdominal segments of the adult mosquito, with the pedipalps (claws) grasping the posterior edge of the 1st abdominal sternite and the prosoma oriented anteriorly. One female Cx. tarsalis carried 2 Cheiridium sp. (1♂, 1♀), one shingled upon the other, at the typical attachment site.

In laboratory experiments fifth instar Dicosmoecus atripes (Hagen) larvae formed aggregations under uniform environmental conditions, variations in which (e.g. current, substrate, etc.) could function in bringing larvae together to a 'suitable' site of attachment in the field. In selecting an attachment site, larvae selected substrates with attached conspecifics already present over substrates without attached conspecifics. Given the choice between an attachment site with empty nonspecific larval cases attached or glass shell-vials similarly attached, D. atripes larvae chose the site with nonspecific larval cases. It appears that D. atripes larvae are capable of tactile or visual recognition of conspecifics, and use their presence as cues in attachment site selection. There was no experimental evidence of chemical cues between larvae in aggregation formation.

A straight anteromedial incision for the exposure of the medial, posteromedial, and posterior ligaments of the knee provides favorable exposure of the distal attachment site of the posterior cruciate ligament. This approach enables a medial parapatellar arthrotomy to be performed through the same incision. The key elements of the exposure are the reflection of the semimembranosus tendon and detachment of the posterior capsule from the medial meniscus.

The parasitic copepod,Argulus laticauda, was found to exhibit a seasonal and body attachment site preference on the oyster toadfish,Opsanus tau, captured at Solomons, Maryland, Comments are presented on the number of fish parasitized, size, distribution and abundance of the parasites, and associated ecological conditions during the period June 26–October 12, 1961.

Radiation inactivation of P/sup 3//sup 2/-labeled vaccinia virus indicates that the virus possesses one or two sites which are responsible for attachment to the host cell. The sensitive volume of the attachment site was found to correspond to a molecular weight of about 3 million. The sensitive volume of the unit controlling pock formation by vaccinia was found to be equal to 4% of the nucleic acid volume of the virus. The implications of the ratio of the nucleic acid volume to radiosensitive volume are discussed. (auth)