emm typing and validation of provisional M types for group A streptococci

This report discusses the following issues related to typing of group A streptococci (GAS): The development and use of the 5' emm variable region sequencing (emm typing) in relation to the existing serologic typing system; the designation of emm types in relation to M types; a system for validation of new emm types; criteria for validation of provisional M types to new M-types; a list of reference type cultures for each of the M-type or emm-type strains of GAS; the results of the first culture exchange program for a quality control testing system among the national and World Health Organization collaborating centers for streptococci; and dissemination of new approaches to typing of GAS to the international streptococcal community.     

Gorlin's syndrome: Diffuse appendicular skeletal involvement with scintigraphic correlation

Gorlin's syndrome (also known as basal cell nevus syndrome, Gorlin?Goltz syndrome, and nevoid basal cell carcinoma syndrome) is a rare, inherited disorder characterized by multiple basal‐cell epitheliomas, intracranial calcification, keratocysts of the mandible, and unusual and striking skeletal abnormalities. We present the interesting case of a 45‐year‐old woman who was informed that she had fibrous dysplasia of the extremity at another institution before extensive radiological work‐up showed a diffuse skeletal process. The skeletal abnormalities, in conjunction with the patient's history of multiple basal cell carcinomas, is consistent with the diagnosis of Gorlin's syndrome. We describe this unusual case of striking radiological and scintigraphic findings in a patient with Gorlin's syndrome.     

Vascular smooth muscle mechanics in isolated perfused segments of carotid arteries

BACKGROUND: We hypothesized that smooth muscle contraction and relaxation responses in a muscle bath (isometric tension) would be different than responses of intact vessels (isotonic tension). METHODS: Bovine carotid artery contractile responses to the catecholamine, norepinephrine, and smooth muscle relaxant, 3-isobutyl-1-methylxanthine, were examined in strips of vessels in a muscle bath and in intact whole vessels in an isolated perfused whole-vessel perfusion apparatus. RESULTS: The maximal tension in the muscle bath depended on the length of the strip. The responses of whole vessels to increasing pressure was curvilinear. The maximal decrease in vessel diameter in intact vessels in response to the catecholamine and norepinephrine occurred at low intraluminal pressures. The dose-response curve to norepinephrine was shifted to the left in intact vessels compared with strips of vessels in the muscle bath, which suggests that whole vessels were more sensitive to norepinephrine. The maximal increase in diameter to increasing intraluminal pressure occurred in the presence of the phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine, which suggests that there was significant intrinsic tone in the vascular smooth muscle. CONCLUSIONS: These results suggest that there are differences in the contractile properties of the vascular smooth muscle that are related to the ex vivo system used to examine smooth muscle responses. Responses obtained in isolated perfused whole vessels may more closely approximate in vivo responses.     

Phenotypic diversity in siblings with partial androgen insensitivity syndrome

The androgen insensitivity syndrome is a heterogeneous disorder with a wide spectrum of phenotypic abnormalities, ranging from complete female to ambiguous forms that more closely resemble males. The primary abnormality is a defective androgen receptor protein due to a mutation of the androgen receptor gene. This prevents normal androgen action and thus leads to impaired virilisation. A point mutation of the androgen receptor gene affecting two siblings with partial androgen insensitivity syndrome is described. One had cliteromegaly and labial fusion and was raised as a girl, whereas the other sibling had micropenis and penoscrotal hypospadias and was raised as a boy. Both were shown to have the arginine 840 to cysteine mutation. The phenotypic variation in this family is thus dependent on factors other than abnormalities of the androgen receptor gene alone.     

Actuarial survival in the premature infant less than 30 weeks' gestation

OBJECTIVE: Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation. STUDY DESIGN: We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals. RESULTS: In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age. CONCLUSIONS: Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants.     

Antisense RNA-mediated reduction of p53 induces malignant phenotype in nontumorigenic rat urothelial cells

p53 mutation is commonly associated with high-grade, high-stage human urothelial carcinomas. Recent studies suggest that p53 mutation in low- grade, low-stage bladder carcinomas may be correlated with the progression of the disease. In the present study, we used antisense RNA methodology in vitro to evaluate the significance of the loss of p53 function at an early stage of urinary bladder carcinogenesis. An immortalized nontumorigenic rat urothelial cell line (MYP3) that strongly expresses wild-type (WT) p53 was transfected with a plasmid (pcDL-SR alpha-296) containing a rat WT p53 cDNA in antisense orientation. The transfection resulted in a significant reduction in p53 mRNA expression and protein synthesis, in stimulation of anchorage- dependent growth, and in acquisition of anchorage-independent growth potential. Three such clones, when tested in athymic nude mice, all formed muscle-invasive, high-grade transitional cell carcinomas at s.c. injection sites. When cells were inoculated into an orthotopic site (urinary bladder), one of two antisense transfectants tested formed bulky tumors in the bladder in all seven nude mice and metastases to lungs in three of the seven mice. Analysis of these cells revealed a decrease in the expression of p21 (WAF1, sdi1, or CIP1) and retinoblastoma (Rb) gene product. Phosphorylation of Rb protein was not inhibited when the cells were starved. No significant difference was observed in the expression of p16 protein. In cell cycle analysis, all antisense transfectants tested escaped from G1 arrest by starvation. Furthermore, secretion of interleukin (IL)-6 into culture medium was increased significantly. Treatment with anti-IL-6 antibody suppressed anchorage-dependent growth. This study directly demonstrates that the loss of p53 function at an early stage of urothelial carcinogenesis may result in acquisition of a malignant phenotype by regulating IL-6 production as well as cell cycle related genes.      

Do placental sections accurately reflect umbilical cord nucleated red blood cell and white blood cell differential counts?

OBJECTIVE: Elevated levels of umbilical cord nucleated red blood cells (nRBCs) have been used to assess in utero hypoxia. Although the umbilical nRBC value has been the 'gold standard', umbilical blood may not be obtained at delivery. We determined if the levels of nRBCs and white blood cell (WBC) counts in fixed placental sections might serve as a proxy for cord blood values. STUDY DESIGN: Umbilical blood and placenta were collected from 25 deliveries at Harbor-UCLA Medical Center. Umbilical blood and placental sections were analyzed for nRBCs (per 100 WBC) and WBC differential, and compared with the t-test or the Mann-Whitney rank sum test. RESULTS: nRBC counts were equivalent in umbilical cord and placental sections (5 vs. 4/100 WBC). Umbilical lymphocyte and polymorphonuclear leukocyte (PMN) counts were normally distributed, averaging 35 +/- 9 and 56 +/- 2/100 WBC, respectively. Placental lymphocyte (33 +/- 2/100 WBC) and PMN (60 +/- 2/100 WBC) counts were equivalent to cord blood values. CONCLUSION: WBC differentials and nRBC counts are equivalent in umbilical cord blood and processed placental pathology sections. For infants in whom cord blood cell counts are desired though umbilical cord samples are unavailable, fixed placental sections may serve as a proxy.     

Esophagectomy after pneumonectomy: a surgical challenge

Esophagectomy after pneumonectomy has been reported rarely, and the surgical approach presents a challenge. We report a case of a transthoracic esophagectomy in a 54-year-old man who had undergone right pneumonectomy for non-small cell lung cancer 16 years previously.     

Book reviews

FLOCKS AND FOOD. A BIOCULTURAL APPROACH TO THE STUDY OF PASTORAL FOODWAYS, Michael J. Casimir, Böhlau Verlag, Köln Weiman Wien, 1991, 327 pp, DM 108 ‐.

EVALUATION OF CERTAIN FOOD ADDITIVES AND NATURALLY OCCURRING TOXICANTS. Thirty‐ninth Report of the Joint FAO/WHO Expert Committee on Food Additives. Technical Report Series, No. 828 1992, vi +49 pages (available in English; French and Spanish editions in preparation) ISBN 92 4 120828 7 Sw.fr. 9.‐/US $8.10. In developing countries: Sw.fr. 6.30.

TRICHLORFON. Environmental Health Criteria, No. 132 1992, 162 pages (English, with summaries in French and Spanish). ISBN 92 4 1571322 Sw.fr. 22.‐/US $19.80. In developing countries: Sw.fr. 15.40.

FENITROTHION. Environmental Health Criteria, No. 133 1992, 184 pages (English, with summaries in French and Spanish) ISBN 92 4 1571330. Sw.fr 22.‐/US $19.80. In developing countries: Sw.fr. 15.40.