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M Berry

Publications and source records attributed to M Berry.

At least 37 records · Page 2Linked to original sources
PubMed1991

Immunocytochemical analysis of glial cells in the hypomyelinated optic nerve of the BW mutant rat.

The Browman-Wyse (BW) rat is a mutant with structural defects of the visual system, including a failure of the proximal (retinal) end of the optic nerve to myelinate. This latter abnormality is correlated with an absence of CAII+ oligodendrocytes, but we have previously shown that astrocytes are normally distributed, as judged by morphological characteristics of GFAP+ cells in vivo. We have further examined in vitro the immunohistochemical characteristics of macroglia isolated from the BW optic nerve, either as cell suspensions or after 4 days in culture. Cell cultures derived from the hypomyelinated proximal segment of BW optic nerves contained very few 0-2A progenitor cells (from which oligodendrocytes and cells with the GFAP+/A2B5+ phenotype develop), whereas over 90% of the glia were Schwann cells. A proportion of these few 0-2A progenitor cells differentiated normally after 4 days in vitro into both progeny phenotypes in appropriate media. Accordingly, we conclude that the myelination deficiency in the BW optic nerve could be explained as a failure of 0-2A progenitor cells to populate fully the proximal extremity of the nerve during development. Since most glia isolated from adult optic nerves did not adhere to the culture substrate, we analysed the phenotypes of freshly isolated cells in suspension. Comparing optic nerves of normal adult rats with those of BW mutants, a significantly higher fraction of the GFAP+ cells reacted with A2B5 in cell suspensions of the latter. The double-labelled cells which are present in abnormally high numbers may be the differentiated progeny of 0-2A progenitors in the hypomyelinated segment of nerve. One explanation for these findings is that Schwann cells within the BW nerve induce the differentiation of 0-2A progenitor cells to the GFAP+/A2B5+ phenotype. We investigated this possibility using conditioned medium from cultured Schwann cells which increased tenfold the frequency of GFAP+/A2B5+ cells in normal neonatal rat optic nerve cultures. Oligodendrocyte numbers showed a concomitant decline with increasing concentration of Schwann cell conditioned medium. Hypomyelination in the BW rat optic nerve may therefore arise because Schwann cells, present in the proximal segment of the nerve, not only impede the migration of 0-2A progenitor cells but also release a factor which induces those 0-2A progenitor cells which arrive in the proximal segment of the nerve to differentiate into GFAP+ cells at a critical stage in oligodendrocyte development.

Animals↗
PubMed1991

Computed tomography in untreated congenital adrenal hyperplasia.

Six children with untreated congenital adrenal hyperplasia (CAH) were examined by computed tomography (CT). Three cases demonstrated diffuse enlargement of both adrenal glands with preservation of normal configuration and two showed tumorous transformation in one of the enlarged glands. One had equivocal enlargement of the adrenal gland. Even the youngest in this group (age 2 years) also showed bilateral hyperplasia.

Adolescent↗
PubMed1991

Preoperative chemotherapy for children with Wilms' tumor.

Five years ago, the use of preoperative chemotherapy for Wilms' tumor was adopted at this institution. Thirty children ranging in age from 5 months to 9 years had histologically confirmed Wilms' tumor (needle biopsy, n = 26; open biopsy, n = 4). Stage was determined by chest and abdominal computed tomography (CT) scan. Bilateral tumors were present in 6 children. All children received actinomycin D and vincristine from 3 weeks to 6 months before surgery. Seven children with bilateral tumors or stage IV disease also received adriamycin. CT-measured tumor masses shrunk in most cases. Subsequently, nephrectomy was performed in 23 patients and partial nephrectomy in 4, 2 of whom had bilateral disease. In 2 patients, residual bilateral well-differentiated epithelial tumor was not surgically resected. One child died before surgery. Reevaluation at delayed total or partial nephrectomy resulted in a downstaging of disease in 12 (41%). Further chemotherapy and radiation was based on the surgical stage. Postoperative chemotherapy (4 months to 2 years) was administered to all patients. The chest and/or abdomen were radiated in 12. Four patients (13%) died, 1 of radiation pneumonitis and 3 of the disease progression (2 with unfavorable histology, 1 of whom had bilateral disease). Two of 4 with unfavorable histology and 4 of 6 with stage IV disease have survived. It is concluded that this preoperative chemotherapy protocol is as effective as the National Wilms' Tumor Study (NWTS) protocol. The treated tumor is smaller, less friable, and easier to remove. Furthermore, because of downstaging, less radiation is necessary for cure.

Biopsy, Needle↗
PubMed1991

The construction of human somatic cell hybrids containing portions of the mouse X chromosome and their use to generate DNA probes via interspersed repetitive sequence polymerase chain reaction.

Interspersed repetitive sequence polymerase chain reaction (IRS-PCR) has become a powerful tool for the rapid generation of DNA probes from human chromosomes present in rodent somatic cell hybrids. We have constructed a somatic cell hybrid containing a major portion of the mouse X chromosome in a human background (clone 8.0). IRS-PCR was developed for the specific amplification of mouse DNA using either of two primers from the rodent-specific portion of the murine B1 repeat. Amplification was subsequently performed with clone 8.0 and a subclone, 8.1/1, which retains a small murine X-chromosomal fragment including Hprt and the Gdx locus. A total of 15-20 discrete PCR products ranging in size from less than 500 to greater than 3000 bp were obtained from clone 8.0 with each primer. In clone 8.1/1, a subset of these bands plus some additional bands were observed. Nine bands amplified from clone 8.1/1 have been excised from gels and used as probes on Southern blots. All of the fragments behaved as single-copy probes and detected domesticus/spretus variation. They have been regionally mapped using an interspecific backcross. The probe locations are compatible with those of markers known to be present in clone 8.1/1. These results demonstrate the feasibility of this method as applied to the mouse genome and the high likelihood of generating useful DNA probes from a targeted region.

Animals↗
PubMed1991

Tru-Cut biopsy of mediastinal masses guided by real-time sonography.

Twenty-five patients with mediastinal masses, arising in the anterior, middle and posterior mediastinum but in contact with the chest wall, underwent ultrasound (US) guided biopsy with a Tru-Cut needle to obtain a core biopsy specimen from the mass. In all these patients adequate tissue was obtained for a histopathological diagnosis and no major complications were observed. The advantage of core biopsy over fine needle aspiration cytology in mediastinal masses is that accurate histopathological differentiation, and classification of carcinomas and lymphomas is possible. The advantage of performing real-time US guided biopsy is that puncture of the lung and mediastinal vascular structures is avoided.

Adolescent↗
PubMed1991

Accumulated exposure to ozone and measurement of health effects in children and counselors at two summer camps.

In the summer of 1988 a multiorganizational field health study was conducted at two summer day camps in suburban-central New Jersey. Thirty-four campers and counselors had daily pulmonary function tests performed each afternoon while attending camp during the month of July. The subjects ranged from 9 to 35 years of age. A mobile medical screening van was used to house the spirometric equipment and travel to each camp. Continuous ozone measurements were collected over the 19-test day study period. An intense ozone episode was recorded just prior to and during the first 2 weeks of the study. The campers had an increase in respiratory symptoms with increases in ozone concentrations above 120 ppb. Exposures below 120 ppb ozone were not significantly associated with symptoms. Peak expiratory flow rate in children was the only lung function measure associated with increasing ozone concentrations, with an average loss of 4.74 ml/sec/ppb (P-value = 0.05) for the 8-hr ozone exposure measure. Furthermore, it appears that the early intense exposure to ozone produced a persistent decrease in lung function and baseline shift for three days after the episode that obscured the daily dose-response relationship.

Adolescent↗
PubMed1991

In vitro corneal pathogenicity of Acanthamoeba.

The comparative cytopathic effects of a keratitis and an environmental isolate of Acanthamoeba were studied on confluent monolayers of human and rabbit corneal cells grown in culture. The presence of cells in culture induced excystment of amoebae to the active trophozoite form. Total destruction of cell monolayers was observed to be similar for both isolates, and dependent on incubation time and amoebic concentration. The relevance of these findings to human and experimental Acanthamoeba keratitis is discussed.

Acanthamoeba↗
PubMed1991

Development of a dietary model for the study of mild zinc deficiency in humans and evaluation of some biochemical and functional indices of zinc status.

After a 1-wk baseline period, a dietary regimen was developed to induce mild zinc deficiency in 15 males (aged 25.3 +/- 3.3 y, mean +/- SD). The regimen consisted of 1 wk on a liquid diet containing 0.6 mg Zn/d and molar ratios of phytate to zinc (phy:Zn) and of phytate X calcium to zinc [(phy X Ca): Zn] of 209 and 4116, respectively, followed by 6 wk on a diet based on soy protein and egg albumin containing 4 mg Zn/d and with phy:Zn and (Ca X phy):Zn of 70 and 2000, respectively. Subjects were then repleted with 30 mg Zn/d for 2 wk. Fasting blood and urine samples were taken weekly. Changes were observed in mean plasma (mumol/L) and urinary zinc (mumol/d): baseline 97.0 +/- 10.9 and 8.0 +/- 2.7, depletion 80.1 +/- 13.4 and 4.3 +/- 2.3, and repletion 100.8 +/- 13.6 and 8.2 +/- 3.1, respectively (P less than 0.05); taste acuity (0.05 less than P less than 0.10); and cellular immune responses (P less than 0.05). Activities of plasma angiotensin-1-converting enzyme and acidic alpha-D-mannosidase were unchanged. Mild zinc deficiency was induced by the dietary regimen.

Adult↗
PubMed1991

Normal endoscopic pancreatogram in an Indian referral hospital.

A total of 101 normal pancreatograms were analysed in a major referral hospital in India in an attempt to establish normal standards of pancreatic ductal morphology in Indian population. Ductal position, course, caliber, length and variations of anatomy were analysed. Most often (39%) ampulla was seen at the level of second lumbar vertebra, commonly (54%) within 30-39 mm from the lateral margin of right side of corresponding vertebral body. Most common ductal course (21.78%) was ascending-horizontal-horizontal type. Mean ductal diameters in the head, body and tail of the pancreas were 2.63, 1.95, 0.99 mm in individuals aged less than or equal to 40 yr and 3.31, 2.34, 1.23 mm in those greater than 40 yr, respectively. A significant (r = 0.46; P less than 0.001) increase in ductal size was seen between less than or equal to 40 yr and after 40 yr of age. Mean ductal length was 16.10 and 16.58 cm in subjects less than or equal to 40 yr of age and greater than 40 yr respectively. Duct of Santorini was visualised in 6.6 per cent subjects.

Adolescent↗
PubMed1991

Progeria syndrome with characteristic deformation of proximal radius observed on CT.

The progeria syndrome (Hutchinson-Gilford) is an uncommon disease. A peculiar shape of the proximal radial metaphyseal region caused by an infolding of the cortex was observed on CT in 2 brothers suffering from this disorder, a feature not previously reported. A brief review of the radiologic literature was undertaken. This new observation needs to be further evaluated as it may provide a clinching diagnostic feature of this disease.

Adult↗