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Biomedical subjects

N Watson

Publications and source records attributed to N Watson.

At least 109 records · Page 6Linked to original sources
PubMed1989

The relation between oral movement control and speech.

A large series of neurological patients, selected solely on the basis that they had damage restricted to one hemisphere of the brain, was given a variety of tests of basic speech and praxic function. Within the left-damaged group, patients were further identified as aphasic or nonaphasic, based on preexisting standard tests of aphasia. Subgroups of aphasics were studied on the basis of lesion location, rather than on the basis of aphasia type. The focus of the study was the relation between the production of speech and nonspeech oral movements, particularly across anterior and posterior lesions. Reproduction of single nonverbal oral movements and of single isolated speech sounds was found to be very highly correlated, and both depended selectively on the left anterior region of the brain. This same region was critically important for rapid repeated articulation of a syllable, suggesting that it mediates control at some "unit" level of movement, in a phenomenological sense, for both speech and nonspeech movements. Other "speech" regions in the left hemisphere appeared to be dispensable for the production of single oral movements, whether these were verbal or nonverbal movements. However, for most aphasic patients, an area in the left posterior region was inferred to be essential for production of multiple oral movements, whether nonverbal or verbal, suggesting a critical role in the accurate selection of movements. Within the posterior region, there was further differentiation for multisyllabic speech into a parietal system, which appeared to mediate primarily praxic function, and a temporal system, which appeared to mediate verbal-echolalic function. Aphasias from anterior and posterior lesions resembled "Broca's" and "Wernicke's" aphasia only insofar as they differed in fluency, with anterior aphasics clearly less fluent. Tests of speech comprehension did not differentiate the groups. It is suggested that classifying aphasic patients via lesion location rather than aphasic typology might yield a view of functional subsystems different from those commonly accepted.

Adult↗
PubMed1989

Monitoring the course of cervical carcinoma with the squamous cell carcinoma serum radioimmunoassay.

Serum samples were collected from 611 gynecologic patients for measurement of squamous cell carcinoma antigen levels using the Abbott Laboratories squamous cell carcinoma antigen radioimmunoassay kit. Sixteen of 83 patients (19.3%) with cervical dysplasia and 72 of 135 (53.3%) with primary or recurrent cervical carcinoma had levels above 2.4 ng/mL. In contrast, only seven of 373 women (1.9%) without genital tract squamous cell intraepithelial neoplasia or carcinoma had squamous cell carcinoma antigen levels above 2.4 ng/mL. Fifty-six patients with cervical cancer were followed for correlation of squamous cell carcinoma antigen levels to disease course, and 20 had persistent or recurrent disease after therapy; rising squamous cell carcinoma antigen levels predicted disease in 15 of these 20 patients with recurrence (13 of 15 with elevated pre-treatment levels and two of five with normal pre-treatment levels). Rising squamous cell carcinoma antigen levels preceded the clinical detection of disease in ten patients by a mean of 4.6 months (range 2-7.5 months); in the remaining five, squamous cell carcinoma antigen levels were elevated only when disease recurrence was documented. Although measurement of squamous cell carcinoma antigen levels is not a sensitive screening method for cervical cancer (sensitivity 53.3%), the test has good specificity (94.3%); the majority of patients with false-positive elevations had other genital tract squamous cell neoplasias. The squamous cell carcinoma antigen assay may be a useful aid for monitoring the disease course of cervical carcinoma.

Antigens, Neoplasm↗
PubMed1988

A new revision of the sequence of plasmid pBR322.

A revised sequence in the region immediately upstream from the rop gene of pBR322 is reported. Two base pairs in the accepted sequence do not exist in the plasmid DNA. Specifically, a TA base pair is missing at sequence coordinate 1893 [Sutcliffe, Cold Spring Harbor Symp. Quant. Biol. 43 (1979) 77-90] and an AT base pair is missing at position 1915, giving a total size for pBR322 of 4361 bp. These changes are in a potential translation initiation sequence and probably reflect errors in the original sequence rather than recent evolution of the plasmid.

Base Composition↗
PubMed1988

An acquired Bernard-Soulier-like platelet defect associated with juvenile myelodysplastic syndrome.

Bernard-Soulier syndrome is an inherited bleeding abnormality characterized by thrombocytopenia with large platelets and deficiency of the platelet membrane glycoprotein (GP) Ib-IX complex. We have identified a young female with an acquired Bernard-Soulier-like platelet defect and a coexisting primary myelodysplastic disorder. Abnormal bruising had developed at age 5. A normal platelet count with some giant platelets was noted at age 7. At age 9 she developed a large haematoma following surgery. Laboratory investigation revealed thrombocytopenia and large platelets. Platelet membrane glycoprotein analysis showed a marked deficiency of the components of the GP Ib-IX complex (approximately equal to 25% of normal). Flow cytometry revealed two populations of platelets: a predominant population of large platelets lacking the GP Ib-IX complex and a minor population of normal-sized platelets with normal GP Ib-IX expression. The patient developed progressive anaemia, more severe thrombocytopenia and neutropenia, and circulating blast cells were seen. A bone marrow showed gross hypercellularity with marked dysplasia of all three lineages and increased blasts. Marrow cytogenetic studies showed the presence of monosomy 7 in all metaphases, with an additional trisomy 21 in 10%. Peripheral blood cells were normal 46XX. The above data are consistent with an acquired myelodysplastic syndrome associated with a Bernard-Soulier-like platelet defect.

Bernard-Soulier Syndrome↗
PubMed1988

Sense receptors with electron-dense supporting structures, and centrioles in the nerve fibres of Gieysztoria and Rhinolasius (Platyhelminthes, Rhabdocoela).

The ultrastructure of two types of sense receptors each is described for Gieysztoria and Rhinolasius. In Gieysztoria, one receptor possesses a number of long microvilli, a cilium with a cross-striated rootlet, a septate desmosome, and an electron-dense band apical to the desmosome. The band forms a complex reticulate extension into the base of the receptor. The second receptor is without microvilli, has a cilium with a long cross-striated rootlet, and a septate desmosome with a short basal electron-dense extension or extensions which do not form a complete ring. In Rhinolasius, one receptor possesses a short bulbous cilium without a rootlet, with a septate desmosome of the pleated sheet (comb) type and a weakly developed electron-dense band beneath it. The second receptor has a long cilium with cross-striated rootlet, and a septate desmosome with a weakly developed electron-dense band apical to it. Centrioles were found in nerve fibres of both species.

Animals↗
PubMed1988

Ultrastructure of the protonephridia of Monocelis (Proseriata, Monocelididae).

The ultrastructure of the protonephridia of Monocelis sp. (Platyhelminthes, Proseriata) is described. The terminal part of the protonephridia ('terminal complex') consists of a terminal cell, a proximal canal cell and at least one supporting cell. The nucleus of the terminal cell is close to the rootlets of the cilia which form the flame. The weir consists of longitudinal external (small) and internal (large) ribs containing cross-striated microfilaments and connected by a membrane. External ribs arise from cytoplasm of the terminal cell, internal ribs from the proximal canal cell, although continuity of an internal rib and a terminal cell was observed in one case. The terminal cell also gives rise to internal leptotriches. Two thick cytoplasmic cords connected by a desmosome extend along much of the flame. A maximum of two supporting cells with nuclei close to the weir were found along the weir, separated from it by cell membranes. Cells with nuclei some distance from the weir may be in contact with the weir as well. The internal surface area of protonephridial capillaries is enlarged by lamellae and reticula. The wall of some but not all capillaries possesses one or several desmosomes. There are many lateral flames. Differences between the protonephridia of Monocelis and other 'turbellarians' and the Neodermata are discussed.

Animals↗
PubMed1987

A retrospective review of adenocarcinoma-in-situ and glandular atypia of the uterine cervix.

Between 1978 and 1985, 19 cases of adenocarcinoma-in-situ and 12 cases of glandular atypia have been identified at the Birmingham and Midland Hospital for Women. In 19 cases an associated dysplastic squamous element was identified, 20 of 28 pre-diagnosis smears correctly predicted a glandular lesion, 5 of 17 colposcopically directed biopsies predicted the findings in a larger biopsy (cone biopsy or hysterectomy). Colposcopy provided no additional information with regard to diagnosis. Twelve of 13 patients managed by cone biopsy and 16 of 17 by abdominal hysterectomy have been treated successfully as defined by subsequent normal cytology.

Adenocarcinoma↗
PubMed1987

Ultrastructure of the protonephridial system of larval Austramphilina elongata (Platyhelminthes, Amphilinidea).

The ultrastructure of the flame cell, protonephridial capillaries and excretory pore of larval and embryonic Austramphilina elongata is described. The weir apparatus of the flame cell consists of internal and external longitudinal rods (ribs) connected by a membrane and with many internal and some external leptotriches. Cilia are densely packed and have cross-striated and branching vertical rootlets. Axonemal doublets lose one tubule and decrease in number towards the tip of the cilia. The cell body proximal to the weir apparatus contains a nucleus, numerous mitochondria, Golgi complexes, and many ribosomes. Serial cross-sections of flame cells in embryos revealed that there are no desmosome-connected cytoplasmic cords anywhere along the flame cells; external ribs are in contact with the proximal cytoplasm by means of desmosomes and fuse to form the distal cytoplasmic tube; internal ribs continue as free processes between the flame and the distal cytoplasmic tube. Numerous 'filaments' (microtubules?) extend between the ciliary rootlets and into the cytoplasm of embryonic flame cells. Some free axonemes were seen in the cell body of embryonic flame cells.

Animals↗
PubMed1986

Arteriovenous shunting in quadriplegia.

Arterio-venous shunting has been demonstrated in the limbs of ten subjects with traumatic quadriplegia, as shown by increased venous oxygen concentration and a Doppler sonogram pattern indicative of continuous forward flow. This phenomenon is similar to that seen in the diabetic neuropathic foot, suggesting that autonomic dysfunction is a major factor in the development of foot ulceration in the quadriplegic and in the diabetic.

Foot↗
PubMed1986

Pharmacokinetic study of chloramphenicol in calves using sensitive gas-liquid chromatographic analysis.

Chloramphenicol was given intravenously and intramuscularly to calves and the blood levels determined over 27 hours. At a dosage of 11 mg/kg chloramphenicol was detected in the blood for 25 hours after intravenous and 27 hours after intramuscular administration. The blood levels after intravenous administration indicate that chloramphenicol in animals moves in a two compartment model. Kinetic parameters were determined for intravenous but not intramuscular chloramphenicol treatment. The blood levels of chloramphenicol were higher following intramuscular than intravenous administration from five hours onward. Chloramphenicol distributed quickly and widely throughout the animal's body.

Animals↗
PubMed1985

Lead synovitis in the hand: a case report.

A case is presented in which a .177 air rifle pellet became lodged in a metacarpophalangeal joint of a thirteen year old boy causing lead synovitis and a raised serum lead level. The local and general effects of lead in a joint merit immediate exploration and removal of the material.

Adolescent↗
PubMed1985

Molecular cloning of the gene for the RNA-processing enzyme RNase III of Escherichia coli.

A ColE1 plasmid from the Clarke and Carbon collection [Clarke, L. & Carbon, J. (1976) Cell 9, 91-99] that contains a 14.4-kilobase Escherichia coli DNA insert complements the rnc-105 mutation, which destroys the activity of the RNA-processing enzyme RNase III. This insert and smaller restriction endonuclease fragments derived from it were cloned into the plasmid pBR329. A number of these recombinant plasmids complemented the rnc-105 mutation in a recA genetic background. The smallest cloned fragment that compensated for the rnc-105 mutation was 1.3 kilobase in size. This fragment led to the synthesis of two polypeptides. One of these polypeptides was 25,300 daltons and corresponded in size to the subunit of RNase III. Fragments cloned in opposite orientations led to synthesis of RNase III, indicating that the cloned fragments contained an endogenous promoter. Extracts of an rnc+ E. coli strain containing an rnc+ plasmid had at least 10 times more RNase III activity than did an analogous strain containing the pBR329 plasmid.

Cloning, Molecular↗
PubMed1985

Patterns of injury to the terminal branches of the brachial plexus. The place for early exploration.

Non-operative management has frequently been adopted for closed injuries of the infraclavicular brachial plexus and its branches in the belief that spontaneous recovery is likely to occur, and surgical exploration is performed only if recovery has not occurred in the expected time. This paper correlates the clinical and electrophysiological features with the operative findings in six patients with such injuries. The axillary nerve was ruptured in all six patients, the musculocutaneous nerve in two and the radial nerve in two. When the muscles supplied by a branch of the plexus were denervated, the differentiation between rupture of that branch and a lesion in continuity could only be made by surgical exploration, which should be performed as soon as other injuries permit.

Adolescent↗
PubMed1984

Self cleavage of a precursor RNA from bacteriophage T4.

We found that a precursor of an RNA molecule from T4-infected Escherichia coli cells (p2Spl; precursor of species 1) has the capacity to cleave itself in a specific position. This cleavage is similar to a cleavage carried out by the aid of a protein, RNase F, that has been previously identified. This cleavage could lead to the maturation of an RNA (species 1) found in T4-infected E. coli cells. The reaction is time and temperature-dependent and is relatively slow as compared to the protein-dependent reaction. It requires at least a monovalent cation and is aided by non-ionic detergents. In the absence of detergent the cleavage can occur but at a reduced rate. The substrate does not contain hidden nicks and a variety of experiments suggest that it does not contain a protein. Moreover, we found no indication that the cleavage is due to contaminating nucleases in the substrate or in the reagents. The intact secondary and tertiary structures of the molecule are necessary for the cleavage to occur. The finding of a self cleaving RNA molecule has interesting evolutionary implications.

Base Sequence↗
PubMed1984

Behavioral problems among patients in skilled nursing facilities.

This survey of a 33 per cent random sample (1,139) of 3,456 patients in 42 skilled nursing facilities (SNFs) in upstate New York yielded 64.2 per cent with significant behavioral problems. Of these, 257 (22.6 per cent) of the total sample had what were defined as "serious" problems (i.e., excluding those with only impaired judgment and/or physical restraint orders). Details of the problem behaviors of this group, their previous history, current management, frequency of psychiatric consultation, and adequacy of documentation were analyzed. Median age was the same as the general SNF population, a slightly lower proportion was female, and, while 66.5 per cent had diagnoses indicating organic brain syndrome, very few had specific psychiatric diagnoses, and only 4.7 per cent had been admitted from a psychiatric facility. The attending physician had noted the behavioral problem in the record in only 9.7 per cent and had requested psychiatric consultation in 14.8 per cent of these "serious" cases. The need for more staff training in mental health care, and more physician and psychiatric consultative assistance are discussed.

Aged↗