Glycosylation of human glomerular basement membrane collagen: increased content of hexose in ketoamine linkage and unaltered hydroxylysine-O-glycosides in patients with diabetes

To study the glycosylation of glomerular basement membrane collagen (GBMC) in diabetes, kidneys were obtained at autopsy from 5 patients with insulin-requiring diabetes of long duration and diabetic complications, and from 5 control subjects. Glomeruli were prepared by sieving and collagen was isolated by limited pepsin proteolysis followed by salt precipitations. Amino acid analyses of the collagen preparations, after acid hydrolysis, indicated a composition consistent with that of type IV collagen. No differences in the relative contents of various amino acids, and in particular, 3-hydroxyproline, 4-hydroxyproline and hydroxylysine, were noted between diabetic and control samples. Non-enzymatic glucosylation was assessed by measuring hexose in ketoamine linkage with thiobarbituric acid after conversion to 5-hydroxymethylfurfural. In 4 of the 5 patients studied, glucosylation values exceeded the mean +2 S.D. of the controls; in the fifth subject glucosylation was in the high normal range. No correlation between the severity of diabetes and hexose content of GBMC was noted, however. In further studies, enzymatic glycosylation of GBMC was assayed after alkaline hydrolysis by separation of glucosylgalactosyl-O-hydroxylysine, galactosyl-O-hydroxylysine, and unsubstituted hydroxylysine in an amino acid analyzer. No differences in the relative contents of hydroxylysine-O-glycosides were evident between diabetic and control GBMC. The results suggest that non-enzymatic glucosylation, but not glycosylation catalyzed by collagen glucosyl and galactosyl transferases, is increased in diabetes. The increased carbohydrate content of collagen may lead to decreased turnover and/or excessive accumulations of basement membrane collagen thus contributing to the vascular complications of diabetes.     

Detection of the CD56+/CD45- immunophenotype by flow cytometry in neuroendocrine malignancies

AIMS: Antibodies against CD56 are primarily used in flow cytometric studies to detect natural killer cells. However, they may be useful in the identification of neuroendocrine malignancies, especially if the cells do not express CD45, indicating a non-leucocyte origin. METHODS: A retrospective review was conducted on all solid tissue flow cytometric studies performed between January 1997 and September 2001, to identify all cases with a CD56+/CD45- immunophenotype. RESULTS: Twelve neuroendocrine malignancies (five metastatic small cell carcinomas, three Merkel cell carcinomas, two metastatic undifferentiated neuroendocrine carcinomas, one metastatic pancreatic neuroendocrine carcinoma, and one neuroblastoma) were identified. CONCLUSIONS: CD56+/CD45- neuroendocrine malignancies are only rarely detected in the flow cytometric analysis of solid tissue samples. However, the recognition of this immunophenotype is important to avoid their misclassification as natural killer cell malignancies. Furthermore, flow cytometry assists in the rapid identification of such cases, so that appropriate immunohistochemical studies can be performed to facilitate their correct diagnosis.     

Do antibodies to myelin basic protein isolated from multiple sclerosis cross-react with measles and other common virus antigens?

Immunological activity to various antigens, including brain components, measles and other viruses, has been associated with IgG in multiple sclerosis (MS). One possible explanation for the presence of anti-viral antibodies and antibody to myelin basic protein (MBP) in MS patients is that there are antigenic determinants common to certain viruses and MBP. To assess this possibility, IgG from individual brains and sera from patients with MS, subacute sclerosing panencephalitis (SSPE) and controls was isolated by protein A and MBP-Sepharose affinity chromatography. Antibody to MBP was measured with a solid phase radioimmunoassay and antibody to measles and other viruses by immunofluorescence and/or complement fixation. Anti-MBP activity was detected in brain extracts and sera of all MS patients tested. In contrast to the low levels of antibody to MBP in control brains, high levels of anti-MBP antibodies were found in most of the normal sera. There was no correlation between the presence and levels of serum anti-measles antibodies and the anti-MBP activity. None of the anti-MBP antibodies affinity purified from brain and serum of MS patients reacted with any of the viruses tested, including measles. IgG purified from SSPE patients or from a rabbit hyperimmunized with measles antigen had no reactivity to MBP, despite high levels of anti-measles antibody. It is concluded that there is not direct link between the presence of antibody to MBP and antibody to measles and other viruses in MS patients.     

The caudal regression syndrome in infants of diabetic mothers

Ultrasonography as part of the pre-natal diagnosis in high risk pregnancies may detect a number of fetal malformations that need to be re-evaluated for continuation or termination of pregnancy. Two fetuses, in two different patients with diabetes mellitus, were found to have significant intrauterine malformations detected by ultrasonography at 18 and 20 weeks gestational age, respectively. Post-mortem examination on both fetuses demonstrated the findings known as the caudal regression syndrome. The clinico-pathological features and obstetrical management of diabetic mothers whose pregnancies are complicated with this rare malformation are discussed.     

High prevalence of HPV 16 in South African women with cancer of the cervix and cervical intraepithelial neoplasia

Despite the high prevalence of cervical cancer and cervical neoplasias in South Africa, few studies have been performed in this region to establish which human papillomavirus (HPV) types are associated with the development of high-grade cervical intraepithelial neoplasia lesions and cervical cancer. To investigate these prevalence rates, punch biopsies were obtained from 56 women with cervical cancer and 141 women with histologically diagnosed cervical intraepithelial neoplasia 2 or 3 lesions. Nested polymerase chain reaction (PCR) using consensus degenerate PCR primers was performed for the detection of HPV DNA and HPV typing was done by restriction fragment length polymorphism. Forty-seven (94%) of the cervical cancer and 114 (88%) of the cervical intraepithelial neoplasia 2/3 biopsies were positive for HPV DNA. The prevalence rates of the HPV types detected in the cervical cancer biopsies were HPV 16 (82%), HPV 18, (10%), HPV 33 (10%), HPV 31 (2%), HPV 58 (2%), HPV 35 (2%), and HPV 59 (2%). The cervical intraepithelial neoplasia lesions contained HPV 16 (56.6%), HPV 33 (14%), HPV 31 (10.9%), HPV X (7%), HPV 52 (3.9), HPV 58 (3.1%), HPV 35 (2.3%), HPV 18 (1.6%), HPV 11 (0.8%). Five of the nine fragments that were not typed by the RFLP, designated HPV-X, were sequenced to give HPV6 (1/5), HPV 26 (2/5), HPV 68 (1/5), and candHPV 87 (1/5). HPV 58 was detected in one cervical cancer biopsy and four biopsies from cervical intraepithelial neoplasia grade 3 lesions and was shown to be a previously described variant [Williamson and Rybicki (1991) J. Med. Virol. 33:165-171]. In addition, a cervical intraepithelial neoplasia grade 2 lesion was shown to harbour HPV type HAN2294 (cand HPV 87). The results of this study indicate that cervical cancer and cervical intraepithelial neoplasia 2/3 are largely associated with HPV 16 infection in this group of South African women and, therefore, an effective HPV 16 based vaccine should prevent the development of cervical cancer in a large proportion of women from this region of South Africa.     

Treatment Features Associated with Youth Cognitive Behavioral Therapy Follow-Up Effects for Internalizing Disorders: A Meta-Analysis

Our aim was to investigate whether four treatment features (i.e., the inclusion of parental involvement, goal-setting strategies, maintenance/relapse prevention sessions, the addition of booster sessions) were associated with posttreatment and follow-up effect size of youth cognitive behavioral therapies (yCBTs) for anxiety, depression, posttraumatic stress disorder, and obsessive-compulsive disorder in age groups spanning young children to adolescents. We conducted a random-effects meta-analysis of 106 yCBTs tested in 76 randomized clinical trials from the PracticeWise Database to examine average effects of yCBTs posttreatment and at a later follow-up assessment. We coded the use of parental involvement, goal setting, booster sessions, and maintenance/relapse prevention in each yCBT and conducted random-effects meta-regression analyses to investigate whether these treatment features were associated with yCBT effects at posttreatment as well as at follow-up. Overall, yCBTs produced large pre- to posttreatment effects (d = 1.05), 95% confidence interval [0.94, 1.15], and larger pre- to follow-up effects (d = 1.29), 95% confidence interval [1.18, 1.40]. Metaregression results indicated that parental involvement was significantly associated with larger pre- to posttreatment effect sizes as well as pre- to follow-up effect sizes. Booster sessions, goal setting, and maintenance/relapse prevention were not significantly related to effect sizes at posttreatment or follow-up. Parental involvement may be helpful for maximizing long-term effectiveness of yCBT. Future studies should investigate for whom and under what conditions inclusion of yCBT treatment features is related to the durability of treatment gains.     

Effects of dietary fatty acids on the early stages of neoplastic induction in the rat pancreas. Changes in fatty acid composition and development of atypical acinar cell nodules.

Diets enriched with fat, especially unsaturated fat, promote experimental pancreatic carcinogenesis, but little is known of the effects of individual fatty acids. The effect of stearic and oleic acid on pancreatic fatty acids and atypical acinar cell nodules (preneoplastic lesions) was studied in 14-day-old weanling male Leeds strain rats (n = 60) given the carcinogen azaserine. Rats were allocated to one of six groups: untreated controls (n = 10), 20% stearic acid diet (n = 10), 20% oleic acid diet (n = 10), carcinogen alone (n = 10), carcinogen plus 20% stearic acid diet (n = 10) or carcinogen plus 20% oleic acid diet (n = 10). Azaserine was administered by intraperitoneal injection in a dose of 30 mg/kg at 2, 3 and 4 weeks of age. When total lipid extracts of pancreas were examined, there was an increase in stearic acid in the stearic acid fed group and an increase in oleic acid in the oleic acid fed group, irrespective of carcinogen treatment. The relative content of all other pancreatic fatty acids was suppressed by feeding oleic acid. At 26 weeks, the number and volumetric indices of pancreatic atypical acinar cell nodules was increased only in rats given azaserine and oleic acid. The enhancing effect of oleic acid on pancreatic carcinogenesis may be associated with pancreatic fatty acid changes.     

Heparins as essential antioxidants

Chronically inflamed tissues contain significant concentrations of oxygen radicals, possibly generated by transition metal species such as Fe(II) and Cu(I). In addition, the pH of such tissues may well be lower than that of normal counterpart tissues. In this communication, the effect of variation of pH on the antioxidant activity of caeruloplasmin (a copper-containing acute-phase protein possessing important ferroxidase and other antioxidant activities) and of heparin are reported. Heparin, unlike caeruloplasmin, retains antioxidant activity at low pH. Heparins possess a variety of metal cation-binding chemical groups allowing them to bind damaging Cu(I) and Fe(II) ions and consequently prevent their redox involvement in oxygen radical-generating Fenton reactions. In conclusion, heparins may function as endogenous antioxidants and sequestration and/or oxidation by them, of ions such as Fe(II), may contribute to their effectiveness.

     

Familial insertional translocation of a portion of 3q into 11q resulting in duplication and deletion of region 3q22.1→q24 in different offspring

The use of elongated prophase and prometaphase chromosome preparations has allowed detection of an insertion of a small segment of 3q into 11q in a kindred with 4 balanced carriers and 8 unbalanced offspring. Those with partial 3q deletion have a true multiple congenital anomalies/mental retardation (MCA/MR) syndrome with an appearance suggestive of the Schwartz-Jampel syndrome.