The relationship of imaging techniques to the accuracy of frameless stereotaxy.

OBJECTIVE: We analyzed the accuracy of a frameless stereotactic system using computed tomographic (CT) and magnetic resonance imaging (MRI) scans of different slice thickness and T(1) versus T(2) weighting of MRI. METHODS: An open skull with graphite pegs fixed to its base was used for all scans. CT scans were done with slice thicknesses of 1, 2 and 3 mm. MRI-visible markers were placed on top of pegs for T(1)-weighted and T(2)-weighted MRI scans, which were acquired at thicknesses of 1.5, 3 and 5 mm. For each scan, 3 separate registrations of a probe were performed; the distance between the actual probe location and that displayed on the registered image was noted. Each measurements was repeated 3 times for each registration. RESULTS: Greatest accuracy was achieved with 3-mm-slice CT scans; this was not improved by using thinner slices. T(1)-weighted 1.5-mm MRI scans were 23% less accurate and T(2)-weighted 3-mm scans 37% less accurate. CONCLUSIONS: Frameless stereotaxy should be done using CT scans when the greatest possible accuracy is desired. There appears to be no advantage to using slice thicknesses less than 3 mm. For most craniotomy applications, T(1)-weighted MRI using 3-mm slices provides sufficient accuracy. Lesions imaged only on T(2)-weighted MRI also can be approached with adequate precision using 3-mm scans.

Predicting the rates of success and complications of computed tomography-guided percutaneous core-needle biopsies of the thorax from the findings of the preprocedure chest computed tomography scan.

The authors attempted to determine whether the anatomic characteristics of thoracic lesions and the surrounding lung field, as assessed by the preprocedure chest computed tomography (CT) scan, can assist in predicting the yield of complications or positive results of pathologic examination resulting from percutaneous core-needle biopsies (PCNB). The pathologic diagnoses and procedural complications of 50 consecutive thoracic PCNBs (43 men, age range 19-81 years) performed under the guidance of a single operator (J.A.M.) were recorded. Prebiopsy chest CT findings, including the size, depth, location, and border appearance of the lesion, as well as presence or absence of adjacent emphysema, interstitial fibrosis, bullae, pleural effusions, and the age and smoking history of the patient were correlated with the biopsy results and any ensuing complications. The pathologic analysis in 42 patients (84%) was specific enough to positively impact patient management, with 29 malignant and 13 benign entities. The imaging variables that predicted obtaining adequate tissue for pathologic diagnosis were most importantly large size (especially >35 mm), although irregular lesion margins and increased depth were significant as well. Seven patients (14%) experienced a pneumothorax, only one of which (2%) was symptomatic and required thoracostomy. All patients experiencing a pneumothorax had CT evidence of emphysema or interstitial fibrosis and all biopsied masses in these individuals had spiculated borders, with six (86%) in an anterior location and only one involving the pleural surface. We conclude that the preprocedure CT scan can delineate several characteristics of both the patient and the lesion to be biopsied that can assist in predicting the rates of successful tissue retrieval or pneumothorax during PCNBs.

A study of early fetal growth patterns in twin pairs.

The relationships of sitting heights and body weights of fetal twin pairs were analyzed in comparison with established growth rate standards of singleton fetuses. The apparent rate of growth of individual twins scattered around the average growth curve in the same manner as singletons. In contrast, members of 12 twin pairs with < 125 mm sitting heights, were closely similar in terms of bodily dimensions. Among the 7 pairs with crown-rump lengths of > 125 mm, 4 were discordant, suggesting a deceleration of growth in one of the twin fetuses, starting after the 18th week of gestation.

Effects of one year of supplementation with zinc and other micronutrients on cellular immunity in the elderly.

The objective of this study was to determine the effects of a year of Zn supplementation on Zn concentrations in circulating cells and on cellular immune functions in the elderly. Subjects, aged 60-89, were given a placebo, 15 mg Zn, or 100 mg Zn daily for 12 months. All subjects also received a multivitamin/mineral supplement that contained no additional Zn. Blood samples were drawn and immune functions assessed prior to and at 3, 6, 12, and 16 months after beginning Zn supplementation. Subject diets were also assessed at each visit. Dietary folate, pyridoxine, alpha-tocopherol, copper, zinc, and magnesium were consistently below recommended intakes. Although plasma Zn increased significantly in the 100 mg Zn treatment group, concentrations of Zn in erythrocytes, mononuclear cells, polymorphonuclear leukocytes, and platelets were not significantly increased by zinc supplementation. Natural killer cell activity was transiently enhanced by the 100 mg/day dose of Zn. There was a progressive improvement in delayed dermal hypersensitivity (DDH) and in lymphocyte proliferative responses to two mitogens; this may have been due to one or more components of the multivitamin/mineral supplement administered to all study subjects. The enhancement of DDH was significantly greater in the placebo group than in either zinc treatment group. Thus, zinc had a beneficial effect on one measure of cellular immune function while simultaneously having an adverse effect on another measure of cellular immunity.

Zinc and immunocompetence in elderly people: effects of zinc supplementation for 3 months.

One hundred and three apparently healthy elderly subjects age 60-89 y were randomly assigned to one of three treatments: placebo, 15 mg zinc/d, or 100 mg Zn/d for 3 mo. Plasma Zn was significantly increased only in the 100 mg Zn group. Zn concentrations in erythrocytes, platelets, mononuclear cells, and polymorphonuclear leukocytes were not significantly increased by any treatment. None of the treatments significantly altered delayed dermal hypersensitivity (DDH) to a panel of seven recall antigens or in vitro lymphocyte proliferative responses (LPR) to mitogens and antigens. Fifteen subjects had initially poor lymphocyte proliferative responses that improved in 14 of these individuals during the study; this was not due to Zn supplementation but might have been caused by one or more components of a vitamin-mineral supplement administered to all study subjects.

Zinc and immunocompetence in the elderly: baseline data on zinc nutriture and immunity in unsupplemented subjects.

Zinc nutriture and immune function were studied in 100 subjects, age 60-89 yr. Mean (+/- SD) zinc concentrations found were 84.8 +/- 15.5 micrograms/dL (13.0 +/- 2.4 microM) for plasma, 1.04 +/- 0.24 micrograms (0.016 +/- 0.004 mumol)/10(9) cells for erythrocytes, 4.06 +/- 1.85 micrograms (0.062 +/- 0.028 mumol)/10(9) cells for mononuclear cells, 3.91 +/- 1.77 micrograms (0.060 +/- 0.027 mumol)/10(9) cells for polymorphonuclear leukocytes, 0.53 +/- 0.39 micrograms (0.0081 +/- 0.0060 mumol)/10(9) cells for platelets, and 222 +/- 101 micrograms (3.39 +/- 1.54 mumol)/g for hair. Zinc ingestion was below the RDA in more than 90% of study subjects. The incidence of anergy to a panel of seven skin test antigens was 41%; responses to these antigens were significantly associated with the plasma zinc concentration. Subjects with depressed lymphocyte responses to mitogens had significantly lower platelet and significantly higher mononuclear cell zinc concentrations than those with normal responses.

Heterogeneous distribution of serum prolactin values in apparently healthy young women, and the effects of oral contraceptive medication.

Controversy over effects of oral contraceptives (OCs) on serum prolactin (PRL) levels from retrospective studies suggested performing a prospective study. Statistical analyses of PRL levels in 552 reproductive-age, nonmedicated women indicated a provisionally lognormal distribution of values less than 15 ng/ml, contaminated by a small number of abnormally high values less than or equal to 90 mg/ml. Truncated samples were used to estimate a "normal range" of PRL levels for three subsets of the study sample, classified according to number of weeks after pregnancy. Fifty-microgram estrogen-containing OCs doubled basal PRL levels at 5 to 8 weeks in those whose initial control values fell below 15 ng/ml, but the PRL elevation was no longer evident at 6 months of drug use. These OCs induced a small but significant lowering of PRL at 5 to 8 weeks in those with control levels of 15 ng/ml or higher. Thirty-five-microgram estrogen-containing OCs failed to alter PRL levels at 5 to 8 weeks in those with control values less than 15 ng/ml.

Staphylococcal infections in aging mice.

Aging (17 to 22 months old) and young (1 1/2 to 2 months old) mice were infected with 5 X 10(7) staphylococci. Twenty-eight-day mortality was 70% in senescent mice and 14.3% in young mice. Phagocytosis and intracellular killing of staphylococci by polymorphonuclear leukocytes and mononuclear cells and leukocyte mobilization were studied after intraperitoneal infection. Intracellular killing by polymorphonuclear leukocytes was slightly more effective in young mice but older mice mobilized about twice as many polymorphonuclear leukocytes in a 4-hour period. In older mice the lethality of intraperitoneally-administered staphylococcal toxins and salmonella endotoxin was markedly increased, the mortality rates in old and young mice being virtually identical to those found after intravenous infection with living staphylococci.

Lead poisoning: more than a medical problem.

Medical records of 236 Newark, New Jersey children hospitalized and chelated for lead poisoning in 1977 through 1980 were reviewed to determine whether or not any discernible progress had been made in eradicating the disease since 1972. Results show that the number of treated asymptomatic children, ages 1-6, began to rise after 1976 and was higher in 1980 than in 1972 when the Newark Lead Poisoning Prevention and Control Program first began. Although mean and peak blood lead levels have decreased over the nine-year period since 1972, signaling a lessening of disease severity, the increase in numbers and rates indicates that childhood lead poisoning still exists as an environmental and social problem.

Clusters of cancer mortality in New Jersey municipalities; with special reference to chemical toxic waste disposal sites and per capita income.

The state of New Jersey (NJ), USA, has been thought to have an unusually high cancer mortality rate; this assumption has been based on 1950-1969 mortality data for NJ counties. This study presents an analysis of mortality from major cancers for NJ municipalities during 1968-1977, and correlates cancer mortality rates with several potentially relevant variables. Age-adjusted mortality rates for 13 major cancer sites for 194 municipalities of 10 000 or more people in 21 NJ counties were compared with cancer mortality in the US. Municipality rates were correlated with: distribution of chemical toxic waste disposal sites (CTWDS); annual per capita income; the rates of low birth weight, birth defects and infant mortality of NJ municipalities. Clusters of cancer mortality were observed in 23 municipalities in 10 counties in which a total of 98 age-adjusted cancer death rates were at least 50% above the national rate, and each of these municipalities had at least two race-sex-specific cancers in which the observed number of cancer deaths was greater than the expected number of deaths at the p less than 0.0005 level. Of these 98 excessive cancer death rates, 72% involved the gastrointestinal tract. Most of the municipalities are located in the highly industrialized densely populated northeastern part of the State. Correlation analyses showed a consistent and significant (p less than 0.05) negative correlation between income and cancer mortality in 11 of 12 cancers studied. These analyses also showed a significant positive association between 8 of 12 cancers studied and CTWDS in one or more subgroup populations and lesser associations with birth defects, low birth weight and infant mortality.

Gastrointestinal cancer mortality in New Jersey counties, and the relationship with environmental variables.

The State of New Jersey (NJ) USA has been thought to have an unusually high cancer mortality rate; this assumption has been based on 1950-1969 mortality data for its 21 counties. This paper presents an analysis of gastrointestinal (GI) cancer mortality rates in New Jersey counties during 1968-1977, a comparison with the 1950-1969 rates, and associations between current GI cancer mortality rates and selected environmental variables. Age-adjusted mortality rates for GI cancers were calculated for the 21 NJ counties during the period 1968-1977, and were compared with the period 1950-1969, with the Surveillance, Epidemiology and End Results (SEER) survey and with cancer mortality in the US, 1973-1977. The county rates were also correlated with: the distribution of chemical toxic waste disposal sites; annual per capita income; the rates of low birth weight, birth defects, and infant mortality; chemical industry distribution; percentage of the population employed in chemical industries; the density of population; and the urbanization index for each of the counties. Some of the major findings are: Age-adjusted GI cancer mortality rates (all sites combined) were higher than national rates in 20 of 21 NJ counties. In comparison with national trends, NJ stomach cancer rates have declined less, oesophageal cancer rates have declined more, and pancreatic cancer mortality rates have followed similar patterns. Cancer mortality rates in NJ during the period 1968-1977 significantly (p less than 0.0001) exceeded national rates for cancer of the oesophagus (white male, non-white male), stomach (men and women), colon (white male, white female, non-white female), and rectum (whites only). In 18 of the 21 NJ counties, the observed number of cancer deaths for at least one GI cancer site was significantly greater than expected at the 0.0001 level for at least one population subgroup. Among white men, a significant (p less than 0.0001) excess of observed over expected cancer deaths was observed for three or more GI cancer sites in seven counties. The environmental variables that were most frequently associated with GI cancer mortality rates (except pancreatic cancer) were degree of urbanization, population density, and chemical toxic waste disposal sites. Some of the implications of the study findings are discussed and recommendations made for future investigations.

The rate of early intrauterine growth in twin gestation.

With the use of specimens obtained by induced abortion, the relationships between crown-rump length on the one hand and body weight and menstrual age on the other were investigated in 43 twin fetuses with menstrual ages between 8 1/2 and 21 weeks. This study indicates that the body weight of twins in comparison with length is the same as that of singletons, an indication of the fact that they are not growth retarded. On the other hand, the average crown-rump length when compared with menstrual age is somewhat less than that of singleton fetuses. The possible implications of these findings are discussed in the light of prevailing concepts concerning the growth of twins.

Vanadium, Na-K-ATPase, and potassium adaptation in the rat.

Vanadate is a potent inhibitor of Na-K-ATPase in vitro. It has been suggested that vanadium may function as a cellular regulator of Na-K-ATPase in vivo. To examine this speculation, we studied in rats the effect of high vanadate intake on 1) the tissue levels and distribution of vanadium, 2) basal activity of Na-K-ATPase in various tissues, and 3) the activity of Na-K-ATPase in various organs under conditions of massive chronic potassium loading known to stimulate Na-K-ATPase in the kidney and colon. Despite extremely high tissue levels of vanadium there was no demonstrable effect of the element on the basal activity of Na-K-ATPase. When subjected to chronic potassium loading, rats with high tissue vanadium concentrations underwent potassium adaptation that was associated with a rise in Na-K-ATPase activity in the renal cortex, renal medulla, and colonic mucosa. Further studies are needed to support or refute the thesis that vanadium might be an intracellular regulator of Na-K-ATPase in vivo.

Balance and tissue distribution of vanadium after short-term ingestion of vanadate.

Forty-six female Sprague-Dawley rats (170-200 g) were randomly assigned to one of six treatment groups receiving 0.1, 5.0, or 25.0 ppm dietary vanadium with either normal (0.13 mEq/g) or high (1.82 mEq/g) dietary potassium. Supplemental vanadium was administered as sodium metavanadate. These diets were fed for 2 weeks, and all feces and urine collected. At the end of the treatment period, brain, liver, renal cortex and medulla, whole blood, and plasma were obtained and analyzed for vanadium by atomic absorption spectrophotometry, as were the urine and feces samples. Tissue vanadium concentration increased significantly (P less than 0.00001) with increasing food vanadium content, but were not affected by dietary potassium in spite of the polyuria induced in animals on the high potassium diets. The highest vanadium concentrations were found in the renal cortex and the lowest, in the brain. Although urinary vanadium excretion was higher in animals fed the high potassium diets, a relatively small percentage of ingested vanadium was excreted in the urine. Rats fed diets containing no supplemental sodium metavanadate (0.1 ppm vanadium) were in negative vanadium balance, but their growth was not inhibited. Animals receiving 5.0 and 25.0 ppm vanadium diets retained 39.7 +/- 18.5% of ingested vanadium and excreted 59.1 +/- 18.8% of ingested vanadium in the feces. These values indicate greater absorption and retention of ingested vanadium than found In previously reported investigations.

An apparent small cluster of choroidal melanoma cases.

Three choroidal melanomas were detected in a 2.5-year period in a small community of 3,592 persons. This small cluster represented an incidence about 20 times that expected (P = .0006). The community has an isolated water supply and very little industry. We determined the incidence of cancer in this and two adjacent communities and found no other unexpectedly high incidence. The three patients had no common exposures. Analyses of air and water from the involved community by mass spectroscopy, chromatography, and Ames (mutagenicity) tests were noncontributory. Nine of 60 mice given community water after weaning developed lens opacities eight to 16 months later; electron microscopy showed an abnormal monolayer of cells on the outer surface of the anterior lens capsule. The genesis of this monolayer was not clear. None of the 30 controls showed such lesions.

Modification of an experimental mouse Candida infection by human dialyzable leukocyte extract.

Human dialyzable leukocyte extract (10(7) - 10(8) leukocyte equivalents, containing transfer factor) was administered intraperitoneally to CFW mice the day of and 2 days after intravenous infection with Candida albicans. Tissue Candida populations were determined immediately after and 2, 4, 7 and 14 days after infection. Kidney populations were significantly reduced on 27% of the days studied. Similar reduction in C. albicans census was obtained after injection of leukocyte extracts from donors skin test-positive to Candida antigens or donors negative to Candida antigens by skin test and migration inhibition analyses. There was no evidence of a dose-response relationship for leukocyte extract in the range 10(5) - 10(9) leukocyte equivalents. When mice were primed with C. albicans antigen 4 weeks prior to challenge the efficacy of leukocyte extracts was not augmented. There was no evidence that the infection-reducing effects were related to augmented polymorphonuclear leukocyte mobilization, increased mononuclear clearance of C. albicans, or to a direct toxic effect on C. albicans blastospores. These studies suggest that the reduction in Candida populations was non-specific and give further impetus to the use of the dialyzable leukocyte extracts as non-specific supplements to antibiotics in overwhelming or recalcitrant infections in man.

Treatment benefit functions for a drug abuse rehabilitation treatment system.

While generally justifying the large amount of money invested in the treatment effort, evaluation studies of treatment centers for drug addiction do not offer a rational method of allocating scarce resources among the various available treatment programs. The problem is further confounded by different costs associated with the different programs and also because clients rarely complete the prescribed treatment. We developed functional relationships between treatment outcomes and time in treatment that allow the inclusion of probable length of stay of patients and cost per week for a particular treatment program in the evaluation considerations. The model evolved from a drug addiction treatment system operating in Newark, New Jersey consisting of six different treatment centres. Treatment outcome measures are derived from a psychosocial questionnaire which was administered to patients at appropriate time intervals. The questionnaire probed into the important facets of human behavior as related to the use or non-use of drugs for non-medical reasons. Gompertz curves reflecting treatment benefit are computed for each treatment center by least square fit of the collected data to appropriate differential equations and used together with cost of treatment and treatment retention rates to compute expected net benefit for each treatment center. These enable the researcher to find the treatment centers with the best treatment outcome or alternately with the best expected cost benefit ratio for any patient type.

Control of hepatitis B infection. The role of surveillance and an isolation hemodialysis center.

A 3 1/4-year study assessed intervention approaches for hemodialysis-associated hepatitis. A 12-month retrospective study was followed by one year of prospective surveillance (during which attention to hygienic techniques was encouraged) and then by a 15-month period during which antigen-positive cases were transferred from study centers to an isolation hemodialysis center (IHL). The incidence of hepatitis B infection (HBI) fell 35.9% in study centers during surveillance; this was followed by a 50.0% drop during the IHC phase. The total 67.9% drop during the entire study period was statistically highly significant; the IHC contributed significantly more to the total drop than did surveillance alone. At comparison units, HBI increased 97.9% during the same period. This study indicates that HBI incidence can be markedly reduced by a combination of surveillance and assignment of antigen-positive patients to a separate dialysis unit.

Problems in retrospectively evaluating a large-scale health intervention program.

Some of the major problems encountered in retrospectively evaluating the effectiveness of ongoing community intervention programs, and some approaches to their solution, are illustrated through a detailed description of the methods employed to assess the performance of the Newark Childhood Lead Screening and Control Program between 1970 and 1976. A process analysis, along with a limited product analysis, provided some basis for judging the effectiveness of the intervention program, despite the absence of an a priori research design, the changing characteristics of the population screened, and the limitations to the measurements used to assess the impact of the program. Even through rigorous scientific control is often unattainable when evaluating community programs, some level of critical assessment of programs is needed to determine whether or not they merit continuing public support.