Speech production results in children implanted with the CLARION implant.

Speech production changes were examined in 24 profoundly hearing-impaired children following implantation with the CLARION Multi-Strategy Cochlear Implant. All study participants were implanted below the age of 6, and with 1 exception, the children were congenitally deaf, with little or no auditory experience prior to implantation. A within-subjects design was used in which the children's preoperative speech skills with hearing aids were compared to postoperative performance with the Clarion after 3 and 6 months of implant use. Production skills were evaluated with a measure designed specifically to assess hearing-impaired children's spontaneous use of early developing phonological patterns in words. The results revealed significant improvement over time in 8 of the 9 speech features examined. The greatest improvement occurred between the 3- and 6-month postoperative intervals, with more limited improvement evident between the preimplant and 3-month time periods. The results demonstrate that significant improvements occur in speech production skills in very young children with congenital deafness after they have used current implant technology for a relatively limited amount of time.

Fatal firearm-related injury surveillance in Maryland.

CONTEXT: Maryland began a statewide firearm-related injury surveillance system in 1995. The system now focuses on firearm-related deaths; a system to monitor nonfatal injuries is being developed. The system is passive; it accesses, integrates, and analyzes data collected by Maryland's Office of the Chief Medical Examiner, Maryland State Police, and Division of Health Statistics. OBJECTIVE: To evaluate the surveillance system's ability to ascertain cases in the absence of a standard for the true number of cases. DESIGN: Link records of the same firearm-related death captured by the surveillance system's multiple data sources, comparing the rate of false positives and false negatives, and assessing errors in linkage variables. SETTING: Maryland, 1991-1994. PARTICIPANTS: All deaths occurring in the state of Maryland as a result of a firearm-related injury. MAIN OUTCOME MEASURES: Sensitivity and positive predictive value. RESULTS: The system is extremely sensitive, detecting 99.61% of cases, and it has a very high positive predictive value, with 99.87% of the cases identified from medical examiner's office data being confirmed as actual cases. CONCLUSIONS: Maryland's database of information from the medical examiner's office is highly accurate for ascertaining firearm-related deaths that occur in the state. A unique identifier common across data sources would ease record linkage efforts, and improve the system's ability to monitor firearm-related deaths.

The identification of false positive responses to the pentagastrin stimulation test in RET mutation negative members of MEN 2A families.

OBJECTIVE: The pentagastrin stimulation test is the traditional test used for the identification of asymptomatic individuals in multiple endocrine neoplasia type 2A (MEN 2A) and familial medullary thyroid carcinoma (FMTC). The identification of mutations in the RET proto-oncogene segregating with the disease phenotype in MEN 2A and FMTC families has made it possible to re-examine the validity of using this test for the identification of affected family members. DESIGN: Sequential and single pentagastrin stimulation test data were collected following the identification of RET mutation positive and RET mutation negative members of families with MEN 2A or FMTC. PATIENTS: RET mutations were identified in 16 Australian and New Zealand MEN 2A or FMTC families. An analysis of 39 individuals from these families was included in this study. Thirty-two individuals (14 males, 18 females) had previously been determined as RET mutation negative. Seven individuals (6 males, 1 female) had previously been determined as RET mutation positive. Two RET mutation negative males had thyroidectomy based on prior pentagastrin test results. MEASUREMENTS: Serum calcitonin levels in response to stimulation with pentagastrin were measured at 0, 1, 2, 5 and 10 minutes post injection. Mutation analysis of the RET proto-oncogene was performed in all individuals. In two RET mutation negative individuals from two MEN 2A families, thyroidectomy was performed and C-cells were quantitated in order to determine the diagnosis of C-cell hyperplasia. RESULTS: There was a statistically significant difference (P < 0.013) between RET mutation negative male and female mean peak calcitonin responses of 282 +/- 236 and 96 +/- 62 (mean +/- SD) ng/l respectively. False positive responses to pentagastrin stimulation were identified in seven individuals who were RET mutation negative in two of the 16 families. Histologic examination of the thyroid glands in the two RET mutation negative individuals who had thyroidectomy demonstrated C-cell hyperplasia in one but not in the other. CONCLUSIONS: There is considerable overlap between pentagastrin test results in individuals who are RET mutation positive and those who are RET mutation negative. These results indicate a need for routine performance of RET proto-oncogene analysis on all individuals at risk of developing MEN 2A or FMTC and a coupling of pentagastrin test results and RET proto-oncogene analysis in the decision to proceed with thyroidectomy.

The incidence of defensive firearm use by US crime victims, 1987 through 1990.

It is well known that many crimes in the United States are committed with firearms. Less adequately documented is the frequency with which victims use guns in self-defense. We used National Crime Victimization Survey data to examine incidents where victims employed guns against offenders. Between 1987 and 1990 there were an estimated 258,460 incidents of firearm defense, an annual mean of 64,615. Victims used firearms in 0.18% of all crimes recorded by the survey and in 0.83% of violent offenses. Firearm self-defense is rare compared with gun crimes.

Single-day intravenous pamidronate in Paget's disease.

Although the efficacy of pamidronate (APD) in Paget's disease is established, the optimal dose and regimen are not known. In this article, further findings using a single-day intravenous infusion are reported, comparing the responses of 114 subjects treated with doses of 20 mg (n = 35), 30 mg (n = 26), 45 mg (n = 29), and 60 mg (n = 24). Assessments of clinical and biochemical response were made at 2, 4, 8, 12, and 24 weeks. Patients with persistent disease activity were retreated after 24 weeks. The single-day infusion of APD was followed by a rapid and sustained biochemical response, but in only 24% of patients did alkaline phosphatase (AP) levels normalize. Of patients in whom the serum AP level normalized, 93% had initial values less than three times the upper limit of normal. Although there was no significant difference in response between the lower dosage groups, there was a greater response in patients treated with a higher dose of APD. The percentage decrease in AP from baseline was similar after the first and second infusions. These findings show that a single-day infusion of APD is effective in the treatment of Paget's disease and that a dose-response relationship exists.

Effects of restrictive licensing of handguns on homicide and suicide in the District of Columbia.

BACKGROUND: Whether restricting access to handguns will reduce firearm-related homicides and suicides is currently a matter of intense debate. In 1976 the District of Columbia adopted a law that banned the purchase, sale, transfer, or possession of handguns by civilians. We evaluated the effect of implementing this law on the frequency of homicides and suicides. METHODS: Homicides and suicides committed from 1968 through 1987 were classified according to place of occurrence (within the District of Columbia or in adjacent metropolitan areas where the law did not apply), cause (homicide or suicide), mechanism of death (firearms or other means), and time of occurrence (before or after the implementation of the law). The number of suicides and homicides was calculated for each month during the study period, and differences between the mean monthly totals before and after the law went into effect were estimated. RESULTS: In Washington, D.C., the adoption of the gun-licensing law coincided with an abrupt decline in homicides by firearms (a reduction of 3.3 per month, or 25 percent) and suicides by firearms (reduction, 0.6 per month, or 23 percent). No similar reductions were observed in the number of homicides or suicides committed by other means, nor were there similar reductions in the adjacent metropolitan areas in Maryland and Virginia. There were also no increases in homicides or suicides by other methods, as would be expected if equally lethal means were substituted for handguns. CONCLUSIONS: Restrictive licensing of handguns was associated with a prompt decline in homicides and suicides by firearms in the District of Columbia. No such decline was observed for homicides or suicides in which guns were not used, and no decline was seen in adjacent metropolitan areas where restrictive licensing did not apply. Our data suggest that restrictions on access to guns in the District of Columbia prevented an average of 47 deaths each year after the law was implemented.

Preventing homicide: an evaluation of the efficacy of a Detroit gun ordinance.

BACKGROUND: In November 1986, a Detroit, Michigan city ordinance requiring mandatory jail sentences for illegally carrying a firearm in public was passed to preserve "the public peace, health, safety, and welfare of the people." METHODS: We conducted a set of interrupted time-series analyses to evaluate the impact of the law on the incidence of homicides, hypothesizing that the ordinance, by its nature, would affect only firearm homicides and homicides committed outside (e.g., on the street). RESULTS: The incidence of homicide in general increased after the law was passed, but the increases in non-firearm homicides and homicides committed inside (e.g., in a home) were either statistically significant or approached statistical significance (p = .006 and p = .070, respectively), whereas changes in the incidence of firearm homicides and homicides committed outside were not statistically significant (p = .238 and p = .418, respectively). We also determined that the ordinance was essentially unenforced, apparently because of a critical shortage of jail space. CONCLUSIONS: Our findings are consistent with a model in which the ordinance had a dampening effect on firearm homicides occurring in public in Detroit. The apparent preventive effect evident in the time series analyses may have been due to publicity about the ordinance, whereas the small nature of the effect may have been due to the lack of enforcement.

Immunoreactive serum calcitonin and skeletal histology in chronic renal failure.

Serum calcitonin and serum parathyroid hormone (PTH) were measured in 50 patients undergoing regular haemodialysis for end-stage chronic renal failure, and an analysis of osteoclast and osteoblast activities was made in bone biopsies obtained by iliac crest trephine. Osteoclast and osteoblast activities were studied in a multivariate analysis in relation to factors which might reasonably be thought to influence activity, namely serum calcitonin, serum PTH, serum calcium, serum inorganic phosphate, and bone aluminium. Only serum PTH correlated strongly with osteoclast activity (p = 0.0047). Serum PTH correlated also with osteoblast activity (p = 0.0024). Serum inorganic phosphate correlated negatively with osteoblast activity (p = 0.0082). Serum calcitonin did not correlate with osteoclast or osteoblast activities but did correlate strongly with bone aluminium in a multivariate analysis (p = 0.0078). Bone aluminium did not correlate independently with osteoclast or osteoblast activities. This study affirms the implied powerful role of PTH in influencing osteoclast and osteoblast activities in end-stage chronic renal failure.

The effect of exercise on circulating immunoreactive calcitonin in men.

Moderate-duration exercise increases serum catecholamine and serum calcium levels and might as a result be also expected to increase the levels of circulating serum immunoreactive human calcitonin (HCT). To explore this possibility, HCT was studied during and after moderate duration symptom-limited dynamic exercise in 13 healthy males, mean age 28 +/- 6.9 (SD) years. The mean duration of exercise using the Bruce treadmill protocol was 14.1 +/- 2.2 (SD) minutes. The mean heart rate (HR) peaked at 185 +/- 6 (SD) bpm which was 96.1% of the predicted maximal HR for age. Values for HCT, uncorrected for changes in plasma volume, showed a minimal decrease in the recovery phase, whilst HCT corrected for changes in plasma volume did not alter during exercise or recovery. The serum parathyroid hormone (PTH) also did not change. At peak exercise, uncorrected but not corrected values for plasma noradrenaline, adrenaline and dopamine had increased significantly. Corrected plasma total calcium increased during recovery. In summary, dynamic weight-bearing moderate-duration exercise did not elevate HCT in healthy males.

Hepatic osteodystrophy. Static and dynamic bone histomorphometry and serum bone Gla-protein in 80 patients with chronic liver disease.

To study the pathogenesis of osteoporosis in patients with chronic liver disease, we performed dynamic bone histomorphometry and measured serum bone Gla-protein in 80 patients with various types of chronic liver disease. These results were compared with results obtained in 40 healthy controls. Mean trabecular bone volume and mean trabecular thickness were significantly reduced in both men and women with chronic liver disease (p less than 0.001 for both measurements in men and p less than 0.01 for both measurements in women). Osteoporosis as defined by histologic parameters was present in 17 (21%) patients with no significant differences in prevalence rates among the various hepatic disorders. No patient had histologic evidence of osteomalacia, although mineralization lag times were prolonged (p less than 0.01 for men and women). Bone formation rates were significantly reduced in 46 (57%) patients, and unlike the static measurements, were related to the type and severity of the underlying liver disease. Patients with alcoholic liver disease, hemochromatosis, and cholestatic liver disease had lower bone turnover rates and osteoblastic surfaces (p less than 0.001 and p less than 0.05, respectively) than patients with chronic active hepatitis. Furthermore, the presence of hepatic cirrhosis was associated with diminished bone formation and lower osteoblast surfaces. Serum bone Gla-protein levels were significantly correlated with bone formation rates and osteoblast surfaces (r = 0.585 and r = 0.434, respectively). A reduction in osteoblast surfaces has not previously been demonstrated in liver disease. This reduction and the associated impairment of osteoblastic activity may contribute to the pathogenesis of osteoporosis and can be assessed by the measurement of serum bone Gla-protein.

Bacteriuria due to ureaplasmas and other fastidious organisms during pregnancy: prevalence and significance.

When urine, which has been collected by suprapubic bladder aspiration, is appropriately cultured, asymptomatic bacteriuria due to fastidious organisms can be detected quite commonly in apparently healthy pregnant women; Ureaplasma urealyticum and Gardnerella vaginalis can each be isolated from the bladder urine of 10 to 15% of subjects, other bacteria less frequently. Both organisms are often present together, sometimes in addition to "conventional" urinary pathogens. Overall bacteriuria occurs in about 25% of healthy pregnant women, including 6% with "conventional" asymptomatic bacteriuria. Pyuria occurs in about one-third of patients with fastidious bacteriuria. Bacteriuria due to fastidious bacteria occurs significantly more commonly in selected groups of pregnant women. U. urealyticum or G. vaginalis or both can be isolated, generally in relatively high numbers from more than 70% of pregnant women with renal disease and 20 to 30% of those with preeclampsia. In a prospective study in which urine was collected using an open ended catheter, ureaplasmas were isolated 3 times more frequently from women less than 25 years of age than from older women. Women with Ureaplasma bacteriuria at the first antenatal visit were 3 times more likely to develop preeclampsia than those without, but the mean birth weights of the infants born to the two groups of women were not significantly different. Further studies are required to determine the importance of these preliminary findings.

Hypervitaminosis A and calcium-regulating hormones in the rat.

The effect of vitamin A on calcium-regulating hormones was studied in rats. A single oral dose of 30 mg retinol equivalents (RE) given to adult rats caused no change to serum biologically active parathyroid hormone (bioactive-PTH) concentrations. Bioactive-PTH secretion from rat thyroparathyroid gland complexes was not significantly altered after in vitro incubation with 1.18 X 10(-6) M retinol. Chronically intoxicated rats given 15 mg RE 3 times a week for 6 wk, showed higher osteoclast numbers and lower osteoid than controls. Serum bioactive-PTH was not detectable and serum 25-hydroxyvitamin D (25-OHD) (25.2 +/- 12.5 nmol/L) was significantly (P less than 0.03) lower than controls (43.3 +/- 3.1). In acutely intoxicated rats (60 mg RE/d for 2 d), serum bioactive-PTH levels were significantly lower (0.02 +/- 0.05 ng/ml, P less than 0.03) than in control animals (0.14 +/- 0.08). Lower doses of vitamin A, 7.5 mg RE 3 times a week for 3 wk, suppressed serum bioactive-PTH to undetectable levels but had no significant effect on serum 25-OHD. Serum calcium and 25-OHD levels were significantly lower in vitamin D-intoxicated rats given 7.5 mg RE 3 times a week (ca. 3.16 +/- 0.19 mmol/L; 25-OHD 599.7 +/- 110.6 nmol/L) than vitamin D-intoxicated controls (3.42 +/- 0.17; 789.3 +/- 17.7). These results suggest that hypervitaminosis A can alter the metabolism of calcium-regulating hormones.

Effect of high-dose dexamethasone on outcome from severe head injury.

The conflicting evidence concerning the influence of high-dose steroids on intracranial pressure (ICP) and outcome following severe head injury has led to the institution of the prospective double-blind controlled trial reported here. Severely head-injured patients admitted to intensive care during a 3-year period were randomly allocated to a dexamethasone- or placebo-treated group. Adults in the steroid group received dexamethasone, 50 mg intravenously, as a bolus on admission to the neurosurgical unit, then 100 mg on Days 1, 2, and 3, 50 mg on Day 4, and 25 mg on Day 5 on continuous intravenous infusion. Children received proportionate intravenous dosages calculated on a weight basis. Severity of head injury was assessed from admission Glasgow Coma Scale (GCS) scores and the appearance of the admission computerized tomography scan. Intracranial pressure (ICP) was monitored in all patients from the surface subarachnoid space. Outcome at 6 months was assessed using the Glasgow Outcome Scale. Steroid and placebo groups were similar in terms of admission GCS score, intracranial pathology, incidence of associated injuries, and time interval from injury to admission to intensive care. The ICP generally increased during the first 48 hours of intensive therapy; there was no difference in this trend between the steroid and placebo groups. A poorer outcome was observed in patients with elevated ICP who received steroids. No increase in the incidence of pulmonary, gastrointestinal, or other extracranial complications was seen in the steroid group. The 6-month outcome did not differ between the steroid and placebo groups. No advantage of high-dose dexamethasone on ICP trends or clinical outcome in the treatment of severe head injury has emerged from this study.

Poverty and Homicide in Detroit, 1926-1978.

The effect of poverty on crime is a controversial issue, mostly because past research has produced only weak evidence of a relationship between economic hardship and crime rates. A review of the literature suggests, however, that time-series data have not been fully exploited in studies of the poverty-crime relationship. This paper helps fill that gap by presenting a regression equation that links poverty and the homicide rate in Detroit from 1926 to 1978. The equation uses a measure based on the infant mortality rate in order to avoid problems associated with monetary indicators of poverty, and it allows for lagged effects across time. The results strongly support the idea that increases in the level of poverty lead to increases in homicide rates.

Comparison of etomidate and althesin in the reduction of increased intracranial pressure after head injury.

The increasing use of shorter-acting hypnotic agents to control intracranial pressure (ICP) following severe head injury has prompted a prospective double-blind controlled trial comparing the efficacy of etomidate and Althesin, given by i.v. infusion. Over the dose ranges used, the two drugs appeared equipotent in decreasing ICP whilst preserving cerebral perfusion pressure. However, in two patients (one in each group) ICP did not respond to hypnotic infusion, a feature noted in other studies to occur in a minority of patients. With the cessation of Althesin manufacture and the discussion about the use of etomidate infusions, it is timely to document the effectiveness of etomidate in decreasing ICP.

Assessment of Leeds device for monitoring intracranial pressure.

In Leeds a screw device is used to monitor surface subarachnoid pressure following severe head injury. The possibility that such measurements may under-read true intracranial pressure (ICP) has led to the development of an infusion test to confirm free communication with the surface subarachnoid space. The results of 69 infusion tests using 18 devices reveal that the device was reading accurately on 33 of 69 occasions. In 31 of the remaining 36, correction of the problem was possible. Particularly at ICP values exceeding 20 mm Hg the Leeds device may under-read, and possible causes for this are discussed. Reliable readings can usually be obtained using the infusion sequence described.

Blood-brain barrier function following drug-induced hypotension in the dog.

To examine the effects of hypotension induced either with trimethaphan (TMP) or nitroprusside (NTP) on blood-brain barrier (BBB), penetration of Evans blue (EB) was observed in dogs anesthetized with halothane. Dogs given TMP were divided into two groups: Group 1, seven dogs rendered hypotensive to mean cerebral perfusion pressure (CPP) of 45 mmHg for 45 min and then of 30 mmHg for 45 min; Group 2, three dogs examined 3 days after arterial hypotension identical to that in Group 1. Dogs given NTP were divided into four groups: Group 1, seven dogs rendered hypotensive with NTP (at dose less than 1 mg/kg) identical to the TMP-Group 1; Group 2, three dogs examined as the TMP-Group 2; Group 3, seven dogs rendered hypotensive to CPP 45 mmHg for 45 min; Group 4, seven dogs rendered hypotensive with NTP (at dose greater than 1 mg/kg) identical to the NTP-Group 1. In all dogs, the dorsal cortical surface and standardized serial coronal sections were examined for evidence of EB penetration. The mean EB penetration score (+/- SEM) for TMP-Groups 1 and 2 was 12 +/- 6, 0 +/- 0, respectively, and for NTP-Groups 1, 2, 3, and 4 was 105 +/- 14, 30 +/- 7, 6 +/- 6, and 125 +/- 26, respectively. These results suggest that dysfunction of the BBB in the NTP group was more pronounced than in the TMP group.

Effects of 2% enflurane on intracranial pressure and cerebral perfusion pressure.

Ten patients with cerebral tumours were anaesthetized with thiopentone, 70% nitrous oxide in oxygen and fentanyl. Ventilation was controlled to give mean PaCO2 4.8 (range 3.6-6.7) kPa. Enflurane 2% was administered and ICP and MAP were recorded continuously for 10-15 min. The changes in ICP were not significant and ranged from -18.5 to 5.5 mm Hg. There were significant decreases in MAP (P less than 0.001) and CPP (P less than 0.001) during the administration of enflurane. In four patients the administration of enflurane had to be terminated prematurely because of a low CPP. Thus, enflurane has very little effect on ICP in patients with cerebral tumours and low concentrations of enflurane can safely be used during anaesthesia for intracranial operations, provided that the arterial pressure is monitored carefully.

Bacteriuria due to Ureaplasma urealyticum and Gardnerella vaginalis in women with preeclampsia.

Certain fastidious organisms such as U urealyticum and G vaginalis can be isolated from the aspirated bladder urine of pregnant women more frequently than conventional urinary pathogens such as Escherichia coli [1]. They can be isolated even more often from the aspirated bladder urine of patients with renal disease, but rarely from that of healthy men or nonpregnant women [2]. We investigated the incidence of bacteriuria due to these two organisms--particularly U urealyticum--in patients with preeclampsia. U urealyticum was isolated more frequently (rate, 20%), and usually in higher colony counts, from the urine of patients with preeclampsia than from that of healthy pregnant women (rate, 7%). G vaginalis was isolated with approximately the same frequency as U urealyticum from specimens of bladder urine; both organisms were isolated from the urine of 11 patients (eight healthy women and three with preeclampsia). High colony counts of G vaginalis were also found more frequently in patients with preeclampsia. In both groups other fastidious organisms were isolated in a total of only five patients, and in four of these five cases U urealyticum and/or G vaginalis were also isolated from the same specimen. Urine cultures were more frequently positive in patients with moderately severe hypertension (blood pressure, greater than 160/100 mm Hg) than in those with mild hypertension (blood pressure, 140/90-160/100 mm Hg, occurring in nine (53%) of 17 patients and in nine (26.5%) of 34 patients, respectively. This difference was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)