The relationship of multifocality and tumor burden with various tumor characteristics and survival in early breast cancer.

The presence of multifocality and the aggregate tumor size were retrospectively analysed in a database of 1071 operated breast cancers. Around a quarter of all these cancers involved multiple foci, while a tenth of the total demonstrated more than one invasive focus. Although the multifocal cancers were smaller and more often screen-detected than the unifocal cancers, their aggregate tumor size was larger, and they more frequently displayed casting-type calcifications in the mammogram and HER2 positivity. Lobular histology favoured larger tumor burden. The invasive multifocal cancers were more commonly lymph node-positive than the other tumors. In a subgroup of 584 patients with a median follow-up time of 5 years, the larger size of the invasive tumor, the presence of LVI or lymph node involvement, HER2 positivity and triple negativity were associated with a poorer RFS and OS, while the outcome of screen-detected tumors was superior to that of non-screen-detected or interval cancers. A large tumor size, lymph node positivity and HER2 positive or triple negative phenotypes were independent determinants of a poorer survival rate.

Initiation of aerial mycelium formation in Streptomyces.

In the past two years, the isolation of extracellular factors involved in the initiation of aerial mycelium formation, the identification of metabolic defects in certain developmental mutants, and the characterisation of three further bld genes and several gamma-butyrolactone receptor genes have led to new ideas about the mechanisms that initiate aerial mycelium formation in Streptomyces. The emerging picture suggests the integration of numerous signals from both inside and outside the cell.

The role of alkalication in formation and decomposition of myosin-ATP complex.

The dependence of kinetic constants Km, V(k2) and k1 of myosin-ATPase on the species and concentration of alkali cations and on temperature was investigated. The value of Vvaries with the ionic radius of different alkali cations. The curve has a maximum at 1.33 A at the ionic radius of potassium. The detailed analysis of the cation dependence of the kinetics of the ATPose reaction shows that both formation and decomposition of the complex are affected by the cation present.

Cloning and characterization of gentamicin-resistance genes from Micromonospora purpurea and Micromonospora rosea.

Aminoglycoside-resistance genes (grm) were cloned from a gentamicin producer Micromonospora purpurea and a sisomicin producer Micromonospora rosea. The nucleotide (nt) sequences of both genes were determined and the similarity between them was very high (90.4% identity). In either case, the transcription start point was localised to about 11 nt upstream from the likely translation start codons of grm, which is expressed as a polycistronic transcript. In studies to be reported elsewhere, it has been established that the M. purpurea grm gene encodes a ribosomal RNA methyltransferase. Here, we confirmed that the similarity of the two genes exists not only at the structural but also at the functional level.

The cochlear aqueduct: structural considerations.

Perusing 170 series of temporal bone sections, the course of the aqueduct was found to be a spindle shape, based on numerous dilatations in the middle section. Ample space was offered for development of bony excrescences such as exostotic depositions and osteoma-like protrusions of all sizes. These added considerably to the difficulties of a free passage through the aqueduct.

Temporal bone findings in cases of salt water drowning.

The otologic literature contains no description of the histopathological features of temporal bones of persons who perished in drowning accidents. Three temporal bones from two fatal cases of drowning were studied in serial sections. Two temporal bones were from a man aged 31 years who collapsed after scuba diving and died three days later. One temporal bone was from a 32-year-old man, serving in the navy, who drove his car, probably accidentally, into the sea and drowned in it. Histopathological findings appeared to be similar in the two cases. Diffuse hemorrhage was evident throughout the middle ear and inner ear. The tympanic and round window membranes appeared to be intact although hemorrhage had occurred within the tissue layers of the membranes. This finding contrasts with observations of ruptured membranes by other investigators.

Temporal bone showing otosclerosis, paget's disease and adenocarcinoma.

In a pair of temporal bones serial sectioning revealed widespread Paget's disease with otosclerosis on both sides and, at the right side, adenocarcinoma added. Stapedial fixation was produced on the right by otosclerosis, and on the left by Paget's disease. In the contest to reach the inner cochlear space, Paget was the winner on the left, where, at the tympanic scala, otosclerosis and Paget's disease almost met, while the immediately adjacent organ o Corti was uninvolved.

Penetration of the cochlear endost by the fibrous component of the otosclerotic focus.

The role of the "third", "fibrous" component of the otosclerotic focus in penetrating and absorbing the cochlear endost is documented. An otosclerotic focus rich in fibrous-granulomatous component shows equal power as spongiotic or sclerotic components producing fragmentation resulting in rosary-formed absorption of the endost opening access to the soft-tissue containing regions of the cochlea.

Anatomical observations on the distal extremity of the vestibular aqueduct.

A hitherto unobserved channel was observed, opening from the bony vestibular aqueduct under the dura. The location was in the centre between the contact of the aqueduct with the bulbar wall and the entrance of the aqueduct into the saccus. No connection was found between this formation and the vascular channels leading into the aqueduct or with the 'paravestibular canaliculus'. Albeit some of the examples were taken from Menière cases no interpretation in this direction was attempted. Strategical location claims further consideration as to morphology and function.

Further observations on the vestibulo-dural channel.

A channel between the vestibular aqueduct and the dura, corresponding in texture to the main aqueduct, has been observed in an un-negligible number of cases. All attempts to establish a connection between this phenomenon and a variety of clinical entities, among them Menière's disease, have so far been unsuccessful.