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Biomedical subjects

M Berry

Publications and source records attributed to M Berry.

At least 235 records · Page 13Linked to original sources
PubMed1990

Balloon dilatation of esophageal strictures.

The Gruntzig balloon dilatation catheter is an invaluable tool for the dilatation of long and narrow oesophageal strictures which are not amenable to other forms of dilatation. We present our experience of 43 dilatations of oesophageal strictures in 14 patients without any significant complications. This procedure resulted in significant symptom-free periods in all patients, and the resultant improved nutritional status of these patients prepared them for surgery.

Catheterization↗
PubMed1990

Hydrometrocolpos: diagnosis and follow-up by ultrasound--a case report.

Hydrometrocolpos is accumulation of secretions in the vagina and uterus, caused by excessive intrauterine stimulation of the infant's cervical mucous glands by maternal oestrogen in the presence of an intact hymen (Wilson et al 1978). Hydrocolpos is dilatation of the vagina proximal to a congenital obstruction. If the uterus is also dilated, the condition is called hydrometrocolpos. Most cases of hydrocolpos are associated with an imperforate hymen that forms a thin bulging membrane between the labia. Though many cases of hydrometrocolpos have been reported in literature, there is no case report which shows classical ultrasound findings and follow up ultrasound scans to show the involuted uterus. We are presenting a case report whose diagnosis was established on ultrasound. This case highlights the value of ultrasound in diagnosing this condition and excluding other associated renal anomalies.

Body Water↗
PubMed1990

Drinking water contamination and the incidence of leukemia: an ecologic study.

An ecologic study was performed to examine the relation between the incidence of leukemias and the occurrence of volatile organic chemical (VOC) contamination of drinking water supplies within a study area comprised of subpopulations differentially exposed to drinking water VOCs (trichloroethylene and related solvents). Populations served by community water supplies were classified into exposure categories according to VOC contamination status based on 1984-85 sampling data. Leukemia incidence data (1979-84) were collected from a population-based cancer registry. For females, the standardized incidence ratio was elevated only in towns in the highest of three exposure categories. No association was observed in males in any of the exposure categories. A Poisson regression analysis of the data, using finer exposure strata, indicated an increase in risk among females with increasing level of contamination which appeared to be distributed evenly across all age strata. The rate ratio for females at the highest exposure stratum for total non-THM VOCs compared to the least exposed stratum was 1.68. The observed association appears to suggest that drinking water contaminated with VOCs may increase the incidence of leukemia among exposed females, but caution is advised in the interpretation of these results because of the uncertainties inherent in ecologic studies.

Adult↗
PubMed1990

Primary malignant hepatic tumors in children--a clinicoradiological profile.

A retrospective analysis of clinicoradiological records of 14 patients with primary malignant tumors of liver (12 hepatoblastomas, 2 embryonal sarcomas) was done. High levels of alpha feto protein were found in four out of six patients and plain X-ray calcification was seen in 33% of patients with hepatoblastoma. Hepatoblastoma was predominantly (80%) a right lobar, illdefined, heterogenous solid mass, which was mixed attenuating on CT scan with areas of patchy enhancement. Angiography was useful in vascular mapping for surgery. A rare association of congenital dysplastic kidney with hepatoblastoma was noted. The imaging protocol for a malignant hepatic tumor and possible differentiating features from the rare entity of embryonal sarcoma are discussed.

Carcinoma, Hepatocellular↗
PubMed1990

Carcinoma bladder: comparative evaluation of urinary cytology, excretory urography and ultrasonography.

A total of 63 patients with 85 bladder tumors were evaluated with excretory urography (IVU), ultrasonography and urine cytology, before being subjected to cystosocopy and biopsy. An attempt was made to evaluate accuracy of detection by different modalities, individually and combined together. Untrasonography and IVU detected 90 percent and 75 percent of tumors respectively while cytology was positive in 63 percent patients. Ultrasonography was superior to IVU, and, Urinary cytology, despite its low catch, could detect few cases where both the previous mentioned modalities had failed. Larger tumors situated on posterior and lateral walls were consistently detected by ultrasonography. Tumor staging by ultrasonography correlated well with final staging in infiltrating tumors. Thus it is concluded that the two non-invasive procedures, sonography and urine cytology must be routinely used for evaluation of fresh cases and in follow up of bladder tumors.

Adult↗
PubMed1989

Topological Link-Vertex Analysis of the growth of Purkinje cell dendritic trees in normal, reeler, and weaver mice.

The growth of Purkinje cell dendritic trees in normal, reeler, and weaver mice has been defined by using Link-Vertex Analysis. Growth probably occurs in three phases in normal and cortically located reeler trees. Phase I, completed by 7 days postnatum (dpn), establishes a rudimentary tree of 100 segments by random terminal branching. Phase II lasts from 7 to 20 dpn when some 690 and 450 segments are generated in normal and cortical reeler trees respectively. Phase II is initiated by an inductive stimulus mediated by a finite number of parallel fibres. Thereafter, dendritic trees develop a similar topology in normal and cortical reeler Purkinje cells through random interactions between parallel fibres and dendritic growth cones. We have defined this process with the aid of computer simulation techniques. Interactions appear to be restricted to a narrow growth front occupied by the highest centrifugally ordered terminals behind which adhesions occur at a greatly reduced frequency. The cortical reeler tree thus has fewer segments than normal because fewer parallel fibres are available, but it is surprisingly normal in most other respects. Phase III is a period of remodelling and extends from 20 dpn into adulthood when high-ordered terminals are eroded and middle-ordered terminals are added, with no change in total segment number in both normal and cortical reeler trees. Weaver and deeply placed reeler Purkinje cell dendritic trees are not influenced by parallel fibres. Accordingly, their growth is arrested at the end of Phase I, when both types of mutant tree have generated 100 segments by unrestrained random terminal branching. In the absence of parallel fibres, Phase II is not induced and remodelling, characteristic of Phase III, does not occur.

Aging↗
PubMed1989

Regeneration of axons from the adult rat optic nerve: influence of fetal brain grafts, laminin, and artificial basement membrane.

After transection of the optic nerve of adult rats, most of the axons in the proximal stump die and the surviving ones are unable to regenerate into the distal optic nerve. Since the fetal brain has an inherent capacity to regenerate axons, we investigated whether fetal (E16) target regions of optic axons (thalamus and tectum) transplanted to the completely transected optic nerve of adult rats would promote axon regeneration. In control operated rats, axon growth beyond the site of transection was restricted to a few fibers that grew irregularly within the connective tissue scar. By contrast, in grafted animals directed outgrowth of optic axons toward the transplant started at 6 days postoperation (p.o.) and reached its maximum 15 days p.o. and later, when numerous single optic fibers and small axon fascicles had grown toward and into the graft, where they formed arborizations and terminal varicosities. Regenerating optic axons were further advanced than GFAP-positive strands of astroglia that emanated from the proximal optic nerve stump. Laminin immunoreactivity appeared at 6 days p.o. in the zone of reactive astroglia in the terminal part of the optic nerve stump. Later it showed a distribution complementary to the pattern of GFAP immunoreactivity, which it seemd to circumscribe. There was no unequivocal codistribution of laminin immunoreactivity with regenerating axons. In further experiments, target regions from different ontogenetic stages (E14 to neonate and adult) and nontarget regions (E16, cerebral cortex or spinal cord) were grafted to the optic nerve stump. With the exception of the adult grafts, all transplants had effects on axon regeneration comparable to those of E16 target regions. In order to test the effects of extracellular matrix molecules on axon regeneration, a basement membrane gel reconstituted from individual components of the Engelbreth-Holm-Sarcoma (EHS) sarcoma was implanted between proximal and distal optic nerve stumps. No axons were induced to regenerate by this matrix. Likewise, laminin adsorbed to nitrocellulose paper and implanted at the lesion site did not stimulate axon growth from the proximal optic nerve stump. These results indicate that fetal brain is able to induce and direct regrowth of axons from the optic nerve toward the graft across a substrate that is not composed of astroglia or basement membrane components like laminin. The directed growth of axons in the absence of a preformed substrate implies a chemotactic growth response along a concentration gradient mediated by neurotropic molecules released from the graft.

Animals↗
PubMed1989

Fetal brain grafts rescue adult retinal ganglion cells from axotomy-induced cell death.

After intraorbital transection of the optic nerve of adult rats, 90% of the retinal ganglion cells die within 30 days. Since fetal brain extracts and cocultured fetal target regions support the survival of retinal ganglion cells in vitro (Nurcombe and Bennett: Exp. Brain Res. 44: 249-258, '81; McCaffery et al.: Exp. Brain Res. 48: 377-386, '82; Armson and Bennett: Neurosci. Lett. 38: 181-186, '83) we investigated whether cell death in the adult retina could be prevented by transplanting fetal (E16) thalamus and tectum to the proximal stump of the optic nerve of adult rats that was completely transected 2-3 mm behind the optic disc. Unoperated eyes contained 119,973 (+/- 939, SEM) retinal ganglion cells, estimated from axon counts of the intact optic nerve. Of these, 11,601 (+/- 1,857) remained in control operated eyes at 30 days postoperation while in the eyes of grafted rats, 35,086 (+/- 2,278) retinal ganglion cells were counted. Thus, 23,485 (= 22% of those normally dying after transection of the optic nerve) ganglion cells were rescued by the fetal grafts from cell death normally following axotomy. These results indicate that fetal target regions of retinal ganglion cells contain and/or produce neurotrophic molecules that promote the survival of adult axotomized retinal ganglion cells.

Animals↗
PubMed1989

The conditioning effect of optic nerve injury upon axonal regrowth from adult rat retinal ganglion cells explanted in vitro.

An in vitro assay was used to determine the effects of conditioning nerve lesions on the regeneration of adult rat retinal ganglion cell (RGC) axons from retinal explants. Following the conditioning lesion (CL) of unilateral optic nerve transection, maximal regrowth was seen from RGC explanted from ipsilateral retinae 10 days post-CL. Explants from this group initiated axonal regrowth earlier and a greater percentage regrew axons when compared with explants from normal rats. Axonal regrowth from explants of retinae contralateral to CL was also seen earlier than normal. In further experiments, the effects of both exposure of the optic nerve sheath in the orbit and the incision of the dura without injury to optic nerve axons were studied. The conditioning effect of a dural incision was found to be the same as that of optic nerve transection, whilst exposure of the optic nerve sheath had no conditioning effect on RGC axonal regrowth in vitro.

Animals↗
PubMed1989

The 5' flanking region of the pS2 gene contains a complex enhancer region responsive to oestrogens, epidermal growth factor, a tumour promoter (TPA), the c-Ha-ras oncoprotein and the c-jun protein.

Expression of the pS2 gene which is transcriptionally controlled by oestrogens in the breast cancer cell line MCF-7 is oestrogen independent in stomach mucosa. We show here that the level of MCF-7 cell pS2 mRNA can also be increased by the tumour promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). We further demonstrate, using transient transfection assays, that the -428 to -332 5' flanking sequence of the pS2 gene contains DNA enhancer elements responsive to oestrogens, TPA, EGF, the c-Ha-ras oncoprotein and the c-jun protein.

Base Sequence↗
PubMed1989

Defective myelination in the optic nerve of the Browman-Wyse (BW) mutant rat.

The Browman-Wyse (BW) rat displays a spectrum of ocular abnormalities which include myelination by Schwann cells of retinal ganglion cell (RGC) axons within the retina. Immunohistochemical and ultrastructural studies of the optic nerves of adult BW rats (30-60 days of age) with myelinated intraretinal axons were performed. Although individual nerves displayed considerable morphological variability, all were characterized by an initial dysmyelinated proximal segment which was separated from a normally myelinated distal segment by a transitional junctional zone. The proximal segment contained axons which were predominantly unmyelinated: where myelination occurred, almost all sheaths were Po-positive, proteolipid protein-negative, and the myelinating cell was a Schwann cell. In the distal segment the distribution of myelinated axons appeared to be normal, sheaths were PLP+, and the myelinating cell was an oligodendrocyte. Within the proximal segment, axons that were myelinated by Schwann cells were isolated by a basal lamina and expanded extracellular spaces from the bulk of other RGC axons within the optic nerve. Few carbonic anhydrase (CAII)+ or GalC+ oligodendrocytes were seen in proximal segments that contained Schwann cells: anti-CAII antibody stained atypical cells within the proximal segments which did not resemble CAII+ oligodendrocytes in the distal segment, and which were probably GalC-. Astrocytes appeared normal throughout the length of the nerve, and there was no morphological specialization at the junctional zone similar to that at the lamina cribrosa. The possible source(s) of the intraneural Schwann cells, and the pathogenetic mechanisms underlying the aberrant myelination of RGC axons within the BW optic nerve are discussed.

Animals↗
PubMed1989

Electron microscopic study of the interaction of axons and glia at the site of anastomosis between the optic nerve and cellular or acellular sciatic nerve grafts.

The interactions between retinal ganglion cell (RGC) axons and glia at the site of optic nerve section and at the junctional zone between optic nerve and cellular or acellular peripheral nerve (PN) grafts have been studied electron microscopically. After transection, RGC axons, accompanied by processes of astrocyte cytoplasm, grew out from the proximal optic nerve stump into the scar tissue that developed between proximal and distal stumps. However, axons failed to cross the scar, and none entered the distal stump. By 3 days post lesion (DPL), bundles of RGC axons, accompanied by astrocytes and oligodendrocytes, grew out from the proximal optic nerve stump into the junctional zone between optic nerve and either type of PN graft. The bundles of RGC axons and growth cones that grew towards acellular PN grafts degenerated within 10-20 DPL; by 30 DPL a small number of axons persisted within the end of the proximal optic nerve stump. No axons were seen within the acellular PN grafts. These results suggest that reactive axonal sprouting, axon outgrowth and glial migration from the proximal optic nerve stump are events that occur during an acute response to injury, and that they are independent of the presence of Schwann cells. However, it would appear that few axons entered either scar or junctional zone unless accompanied by glia. There was little evidence that axon outgrowth was laminin-dependent. The bundles that grew towards cellular PN grafts encountered cells that we have identified as Schwann cells within the junctional zone: the axons in these bundles survived and entered the cellular grafts. Schwann cells migrated into the junctional zone from the cellular PN graft. It is probable that Schwann cells facilitated RGC axon entry into the graft directly by both cell contact and the secretion of neuronotrophic factors, and indirectly by modifying the CNS glia in the junctional zone.

Anastomosis, Surgical↗
PubMed1989

Estrogen-responsive element of the human pS2 gene is an imperfectly palindromic sequence.

Using chimeric recombinants transfected into HeLa cells and a transient expression assay, we demonstrate that the 5'-flanking region of the pS2 gene from position -428 to position -324 exhibits both constitutive and estrogen-inducible enhancer activity. The estrogen-inducible activity, but not the constitutive activity, was inhibited by antiestrogens. ICI 164,384 behaved as a pure antagonist, whereas hydroxytamoxifen was a partial agonist-antagonist. The estrogen-responsive element of the pS2 gene has been narrowed down by site-directed deletion mutagenesis to a 13-base-pair (position -405 to position -393) imperfectly palindromic sequence, which in isolation can confer estrogen inducibility to the heterologous rabbit beta-globin gene promoter. On the other hand, the sequences responsible for the constitutive enhancer activity are spread over the entire region.

Base Sequence↗
PubMed1989

A growth-limiting, mild zinc-deficiency syndrome in some southern Ontario boys with low height percentiles.

A double-blind, pair-matched 12-mo study examined the effects of a zinc supplement (10 mg Zn/d as ZnSO4) on linear growth, taste acuity, attention span, biochemical indices, and energy intakes of 60 boys (aged 5-7 y) with height less than or equal to 15th and midparent height greater than 25th percentiles. Boys with initial hair Zn less than 1.68 mumol/g (n = 16) had a lower mean (+/- SD) weight-for-age Z score (-0.44 +/- 0.59 vs -0.08 +/- 0.84), and a higher median recognition threshold for salt (15 vs 7.5 mmol; p = 0.02) than those with hair Zn greater than 1.68 mumol/g. Only boys with hair Zn less than 1.68 mumol/g responded to the Zn supplement with a higher mean change in height-for-age Z score (p less than 0.05); taste acuity, energy intakes, and attention span were unaffected. A growth-limiting Zn deficiency syndrome exists in boys with low height percentiles, hair Zn levels less than 1.68 mumol/g, and impaired taste acuity.

Body Height↗
PubMed1989

[Interventional computed tomography in thoracic oncology. Apropos of 170 cases].

The authors report their experience with follow-up cytohistological examination of subclinical thoracic lesions in oncology by transparietal puncture with CAT-scanning localization in 170 patients. They detail a few special points concerning the material used and their techniques, in view of reducing the most common incidents and of managing the most severe complications. They analyze their results in two groups of patients, one investigated in a context of known malignancy and the other, with no history of malignancy in whom bronchoscopy, bronchial lavage and brushing were negative. They found an overall sensitivity and specificity of 86% and 100%, respectively, in the diagnosis of malignant disease. The method showed an efficacy of 83.5%. For the two populations, sensitivity was 84% and 87% respectively, and efficacy was 82 and 85% respectively. Thus, the results were better in the patients who had never received anticancer therapy. They also observed significant differences depending on whether the targets were mediastinal, pleuropulmonary or parietal. While the rapid diagnostic information appears invaluable in both groups of patients, in contrast, the small volume of the specimens, which may be hemorrhagic, necrotic, with more or less extensive fibrosis of the stroma, and the immaturity of certain tumors, sometimes make it impossible for the pathologist to give a precise diagnosis of the tumor other than the benign or malignant structural character of the lesion. This represents a significant obstacle in hematology for affections which, although non surgical, nevertheless require precise identification of the lesion for effective therapy. The elaboration of more effective sampling material, repeated punctures and immunohistoenzymatic analysis techniques would probably further improve the results of the method.

Adolescent↗