Autism: Is there a folate connection?

Autism is increasing-but why? Birth defect prevention trials were based on the teleological assumption that folic acid could prevent neural tube defects without consideration of long-term effects, some of which could be beneficial, some of which might be harmful. We therefore ask-Is it impossible to look again at these cohorts?

Assessing the health implications of turbidity and suspended particles in protected catchments.

The supply of unfiltered disinfected drinking water from Melbourne's fully protected catchments means that the water-quality managers must ensure that the source water poses no public health risk. High turbidity is currently used as a surrogate of pathogens, and harvesting of water is based on its measurement. The work presented here summarises suspended particle and associated pathogen, microbial indicator and faecal biomarker concentrations collected to (a) quantify turbidity in an Australian water supply system and (b) assess the possibility of increasing water harvesting from selected tributaries. Pathogens and microbial indicators were present in low numbers in these source waters; increased turbidity during storm events was not associated with an increase in pathogen concentration. The results confirmed that protected catchments, along with good management, were effective barriers to pathogen contamination. Aesthetic issues still need to be addressed, but no measurable increase in microbiological risk was associated with storm-generated particles.

New method for determination of fecal sterols in urine using non-chlorinated solvents.

A new method has been developed to determine a number of sterols in urine using non-chlorinated solvents, namely methyl tert.-butyl ether and methanol (the MTB method). The method involves liquid-liquid extraction, saponification, reextraction, silylation and final identification and quantification by GC-FID. The sterols determined were coprostanol, epicoprostanol, cholesterol and dihydrocholesterol. 5Alpha-cholestane was used as internal standard. The limit of detection for the sterols in this experiment was 2 microg l(-1) urine. Recovery of coprostanol over the range 5-100 microg l(-1) urine by this method was between 80 and 92%.

The origin of red blood cell biopterin.

Data are presented to support the hypothesis that the biopterin content of red blood cells arises during erythropoiesis. Only when the plasma concentration rises above the erythrocyte concentration of biopterin is there likely to be diffusion into the cell.

The potentiality and practicality of a 'salt-free' diet for the prevention and amelioration of human disorders.

The potential of a salt-free diet, which restricts sodium intake to 10 mmol/day, for the prevention and amelioration of human diseases and conditions, may be considerable. Several human disorders may be the result of dietary-salt-generated high-bodily-sodium motility and fluid retention, this being incompatible with the maintenance of bodily homeostasis whenever the body is subjected to stress. Equally importantly, the present-day impracticalities of adopting a 'salt-free' diet appear man-made, and therefore soluble once a sufficiency of purpose exists.

5-Methyltetrahydrofolate level in the serum of depressed subjects and its relationship to the outcome of ECT.

Serum 5-MeTHF levels are reported in 26 subjects, before and after completing a course of ECT, and compared to 21 healthy volunteers. 5-MeTHF levels of depressed subjects were significantly lower than controls before and after ECT. There was no difference in 5-MeTHF levels between ECT responders and non-responders but folate deficiency was related to severity of depression before ECT. Serum 5-MeTHF was not related to treatment response and values remained markedly low even after a good response to treatment.

From the common cold to cancer: how evolution and the modern lifestyle appear to have contributed to such eventualities.

This hypothesis suggests that psychosocial stress is the pivotal determinator of many modern day disorders in consequence to consuming today's nutritional intakes of ascorbic acid and sodium. For it seems, as a result of our tropical African evolution, present day intakes of these essential nutrients are incompatible with the maintenance of bodily homeostasis when the body is subjected to any form of stress. In addition, the climatic conditions under which most of us live are seemingly ill-suited to experiencing stress, since it appears that a constituent part of the bodily stress response remains exclusively designed to be effective in a hot tropical environment, where the stress can be expected to be accompanied by thermoregulation sweating and an overheated body. For without such an occurrence coinciding with stress, the stress response itself appears to have been transposed into a reaction that inhibits the body's ability to resist infection and disease.

Giant nonfunctioning islet cell tumor requiring pancreaticoduodenectomy and complete liver revascularization.

Pancreaticoduodenectomy with revascularization of the hepatic artery and portal vein was performed on a 17-year-old girl with giant nonfunctioning islet cell tumor of the pancreas. She had a remote history of neonatal hypoglycemia leading to mental retardation and a right Wilms' tumor resected at 8 months. Serum pancreatic polypeptide levels were elevated. Her postoperative course was complicated by an ischemic perforation of the colon, which did not infect her prosthetic vascular grafts. The relationship between her neonatal hypoglycemia, Wilms' tumor, and subsequent islet cell neoplasm is unclear.

An improved technique for needle localized biopsies of the breast.

A technique using basic geometric principles is described that allows accurate determination of the location of the nonpalpable lesion in relation to the localizing wire tip and the skin. This method allows the surgeon to make the skin incision directly over the lesion, thus avoiding the creation of tissue flaps and minimizing the amount of tissue removed. While this technique is most helpful for lesions that are remote from the wire tip or buried deep within the breast, these principles are important in all biopsies of the breast. As the number of mammograms performed continues to increase, so will the number of needle localized biopsies, and surgeons must be familiar with techniques to simplify and improve these procedures. Breast conserving treatment for early stage carcinoma of the breast is an accepted form of treatment, and meticulous attention to the technical details of the biopsy will allow it to serve as the definitive surgical procedure. Avoidance of a second operation on the breast is preferable for the patient and will help to reduce health care costs.

Comparison of the abundance of the fecal sterol coprostanol and fecal bacterial groups in inner-shelf waters and sediments near Sydney, Australia.

Concurrent measurement of the sewage tracer coprostanol and fecal indicator bacteria were made for water and sediments collected in January 1992 from coastal waters off Sydney, Australia. The coprostanol results were compared with data from an earlier survey conducted in 1989 before the commisioning of Sydney's deepwater ocean outfalls in 1990 and 1991. Good correlations were observed for both water and sediment samples between coprostanol and the two fecal indicator organisms, fecal coliforms and Clostridium perfringens spores, thereby validating the use of coprostanol as a sewage signature in this environment. For sediments, most inner-shelf sites (1-10 km offshore) showed an increase in the concentration of coprostanol between the two surveys. The areas of highest concentration have been shifted further off-shore, to zones adjacent to the diffusers.

A microtitre plate method for measuring biopterin with cryopreserved Crithidia fasciculata.

The assay of biopterin derivatives in dried blood spots is used by us in initial screening for inherited defects in tetrahydrobiopterin synthesis. The previously described method (1) required aseptic technique and microbiological facilities. The modification detailed here has the advantages of antibiotic cover, which overcomes these needs and microtitre plate technology allowing the incubation time to be halved with precision and accuracy retained. Data reduction facilities may be applied.

Radioimmunoassay that measures serum vitamin B12.

AIMS: To develop a specific radioimmunoassay for the routine determination of serum vitamin B12. METHODS: Antisera were raised in rabbits by immunisation with the monocarboxylic acid derivative of cyanocobalamin coupled to human serum albumin. Antibody titres and affinities were determined and the antiserum giving the highest binding affinity constant, Ka, was used to develop the assay protocol. Donkey-anti-rabbit gamma globulin-coated magnetisable particles were used to separate the bound from free vitamin B12. The considerable cobalamin binding capacity of human serum was destroyed by autoclaving in acetate-cyanide buffer. Sixty samples were assayed by the radioimmunoassay (RIA) and the Lactobacillus leichmannii assay. Recovery and cross-reactivity experiments were performed. RESULTS: Final rabbit antibody titres varied from 1/20,000 to 1/188,000. Scatchard plots did not correlate with the antibody titres. The Ka values varied from 2.6 to 6.7 x 10(10) litres/mol. For maximum sensitivity the highest Ka (titre 1/66,000) was chosen. A tracer concentration of 22 pmol/l, an antiserum dilution of 1/100,000, and a sample volume of 0.1 ml were used. At an antiserum dilution of 1 in 100,000 the cyanocobalamin binding of the rabbit serum was diluted out. The assay showed excellent correlation with the microbiological assay, with 100% recovery of added vitamin B12. Levels of cross-reactivity for dicyanide cobinamide and hydroxocobalamin were 9.8 and 8.1%, respectively. CONCLUSIONS: The development of this immunoassay permits the measurement of serum vitamin B12 without important interference from cobalamin analogues, related corrinoids, and non-specific binders.

Adenoid cystic carcinoma of the breast.

Adenoid cystic carcinoma of the breast is a rare neoplasm, with only 140 cases having been reported to date. Data on 123 of these cases are reviewed herein and another case is presented in detail. Several features distinguish this type of breast cancer from more typical histologic types and suggest that it may have a unique tumor behavior. The prognosis appears to be favorable and the incidence of axillary lymph node involvement is lower. Distant metastases are uncommon, but they tend to occur without prior lymph node involvement. This lack of prognostic significance for negative axillary lymph nodes underscores the need for other prognostic markers in this disease and suggests that axillary dissection can be eliminated in most cases. Similarities to typical breast cancer include the incidence of local recurrence and the lack of effect of surgical treatment on distant metastases and overall survival. These data suggest that breast-conserving treatment may be applicable to adenoid cystic carcinoma.

Inguinal dermoid cyst presenting as an incarcerated inguinal hernia.

A case of an inguinal dermoid cyst presenting as an incarcerated inguinal hernia in a 18-year-old boy is reported. A differential diagnosis of masses in the inguinal region is discussed and includes not only hernias but also gynecologic and vascular lesions. Dermoid cysts must be included in the differential diagnosis. Histologically, these cysts are characterized by an external lining composed of squamous epithelium with an underlying fibroconnective tissue containing hair follicles, sebaceous, eccrine, and apocrine glands. The presence of all the skin appendages in these cysts distinguishes them from epidermoid and sebaceous cysts. The lack of structures foreign to skin differentiates them from dermoids (benign cystic teratomas) in the ovarian, testicular, retroperitoneal, and sacrococcygeal region.

The significance of neopterin and biopterin concentrations at presentation in haematological malignancies.

Urinary neopterin and biopterin concentrations were measured in 32 healthy controls and 53 patients with newly diagnosed haematological malignancies classified and staged by accepted criteria. The neopterin concentrations were only significantly raised in chronic lymphocytic leukaemia at stages III-IV. Total biopterin concentrations after oxidation with iodine at acid pH were decreased in chronic lymphocytic leukaemia stages O-II, multiple myeloma, and acute myeloid leukaemia but not in chronic lymphocytic leukaemia stages III-IV. Although of research interest, neopterin concentrations proved of little prognostic value at presentation, but taken with the biopterin concentration they may be useful for the assessment of tumour activity.

Conservative management of intraductal carcinoma (DCIS) of the breast. Collaborating NSABP investigators.

Seventy-six patients with intraductal carcinoma (DCIS) of the breast have been observed for 83 months (range 50-141) following treatment by lumpectomy (L) only (21), L and breast irradiation (XRT) (27), or mastectomy (28). All represented examples of DCIS retrieved after pathologic examination of a much larger cohort of patients with stage I and II invasive breast cancer enrolled in NSABP protocol 6. Local breast recurrences were similar for women with DCIS and those from this cohort at a similar period of follow-up with invasive cancer treated by L only (43% vs. 39%) and L + XRT (7% vs. 10%). The presence of moderate/marked comedonecrosis was suggestively related to local breast recurrence (P = .07). This latter was significantly reduced for patients receiving post L XRT (P = .01). All local breast recurrences in this study and 29 of 31 recorded by others occurred at or close to the site of extirpation of the index cancer minimizing multicentricity as a contraindication for the conservative surgical treatment of DCIS. Survival rates which were similar for patients with DCIS regardless of form of local treatment were better than that observed for negative node patients with invasive cancer enrolled in protocol 6. Thus, DCIS is a less, not more, ominous disease than invasive cancer. This and other features of its natural history indicate that it would be a contradiction to treat invasive cancer but not DCIS conservatively.